Merge pull request #1624 from alexlamsl/harmony-v2.8.14

Merging from master for 2.8.14

.gitattributes

@@ -0,0 +1 @@
+*.js    text eol=lf

.github/ISSUE_TEMPLATE.md

@@ -0,0 +1,7 @@
+- Bug report or feature request?
+- `uglify-js` version (`uglifyjs -V`)
+- JavaScript input - ideally as small as possible.
+- The `uglifyjs` CLI command executed or `minify()` options used.
+- An example of JavaScript output produced and/or the error or warning.
+
+Note: the release version of `uglify-js` only supports ES5. Those wishing to minify ES6 should use the experimental [`harmony`](https://github.com/mishoo/UglifyJS2#harmony) branch.

.gitignore

@@ -1,2 +1,3 @@
+/node_modules/
+/npm-debug.log
 tmp/
-node_modules/

.travis.yml

@@ -0,0 +1,13 @@
+language: node_js
+before_install: "npm install -g npm"
+node_js:
+    - "0.10"
+    - "0.12"
+    - "4"
+    - "6"
+    - "7"
+env:
+    - UGLIFYJS_TEST_ALL=1
+matrix:
+  fast_finish: true
+sudo: false

README.md

@@ -1,5 +1,6 @@
 UglifyJS 2
 ==========
+[![Build Status](https://travis-ci.org/mishoo/UglifyJS2.svg)](https://travis-ci.org/mishoo/UglifyJS2)
 
 UglifyJS is a JavaScript parser, minifier, compressor or beautifier toolkit.
 
@@ -9,6 +10,9 @@ There's also an
 [in-browser online demo](http://lisperator.net/uglifyjs/#demo) (for Firefox,
 Chrome and probably Safari).
 
+Note: release versions of `uglify-js` only support ECMAScript 5 (ES5). If you wish to minify
+ES2015+ (ES6+) code then please use the [harmony](#harmony) development branch.
+
 Install
 -------
 
@@ -43,57 +47,116 @@ variable/function declared in another file will be matched properly.
 If you want to read from STDIN instead, pass a single dash instead of input
 files.
 
+If you wish to pass your options before the input files, separate the two with
+a double dash to prevent input files being used as option arguments:
+
+    uglifyjs --compress --mangle -- input.js
+
 The available options are:
 
-    --source-map       Specify an output file where to generate source map.
-                                                                          [string]
-    --source-map-root  The path to the original source to be included in the
-                       source map.                                        [string]
-    --source-map-url   The path to the source map to be added in //@
-                       sourceMappingURL.  Defaults to the value passed with
-                       --source-map.                                      [string]
-    --in-source-map    Input source map, useful if you're compressing JS that was
-                       generated from some other original code.
-    --screw-ie8        Pass this flag if you don't care about full compliance with
-                       Internet Explorer 6-8 quirks (by default UglifyJS will try
-                       to be IE-proof).
-    -p, --prefix       Skip prefix for original filenames that appear in source
-                       maps. For example -p 3 will drop 3 directories from file
-                       names and ensure they are relative paths.
-    -o, --output       Output file (default STDOUT).
-    -b, --beautify     Beautify output/specify output options.            [string]
-    -m, --mangle       Mangle names/pass mangler options.                 [string]
-    -r, --reserved     Reserved names to exclude from mangling.
-    -c, --compress     Enable compressor/pass compressor options. Pass options
-                       like -c hoist_vars=false,if_return=false. Use -c with no
-                       argument to use the default compression options.   [string]
-    -d, --define       Global definitions                                 [string]
-    --comments         Preserve copyright comments in the output. By default this
-                       works like Google Closure, keeping JSDoc-style comments
-                       that contain "@license" or "@preserve". You can optionally
-                       pass one of the following arguments to this flag:
-                       - "all" to keep all comments
-                       - a valid JS regexp (needs to start with a slash) to keep
-                       only comments that match.
-                       Note that currently not *all* comments can be kept when
-                       compression is on, because of dead code removal or
-                       cascading statements into sequences.               [string]
-    --stats            Display operations run time on STDERR.            [boolean]
-    --acorn            Use Acorn for parsing.                            [boolean]
-    --spidermonkey     Assume input files are SpiderMonkey AST format (as JSON).
-                                                                         [boolean]
-    --self             Build itself (UglifyJS2) as a library (implies
-                       --wrap=UglifyJS --export-all)                     [boolean]
-    --wrap             Embed everything in a big function, making the “exports”
-                       and “global” variables available. You need to pass an
-                       argument to this option to specify the name that your
-                       module will take when included in, say, a browser.
-                                                                          [string]
-    --export-all       Only used when --wrap, this tells UglifyJS to add code to
-                       automatically export all globals.                 [boolean]
-    --lint             Display some scope warnings                       [boolean]
-    -v, --verbose      Verbose                                           [boolean]
-    -V, --version      Print version number and exit.                    [boolean]
+```
+  --source-map                  Specify an output file where to generate source
+                                map.
+  --source-map-root             The path to the original source to be included
+                                in the source map.
+  --source-map-url              The path to the source map to be added in //#
+                                sourceMappingURL.  Defaults to the value passed
+                                with --source-map.
+  --source-map-include-sources  Pass this flag if you want to include the
+                                content of source files in the source map as
+                                sourcesContent property.
+  --source-map-inline           Write base64-encoded source map to the end of js output.
+  --in-source-map               Input source map, useful if you're compressing
+                                JS that was generated from some other original
+                                code. Specify "inline" if the source map is included
+                                inline with the sources.
+  --screw-ie8                   Use this flag if you don't wish to support
+                                Internet Explorer 6/7/8.
+                                By default UglifyJS will not try to be IE-proof.
+  --support-ie8                 Use this flag to support Internet Explorer 6/7/8.
+                                Equivalent to setting `screw_ie8: false` in `minify()`
+                                for `compress`, `mangle` and `output` options.
+  --expr                        Parse a single expression, rather than a
+                                program (for parsing JSON)
+  -p, --prefix                  Skip prefix for original filenames that appear
+                                in source maps. For example -p 3 will drop 3
+                                directories from file names and ensure they are
+                                relative paths. You can also specify -p
+                                relative, which will make UglifyJS figure out
+                                itself the relative paths between original
+                                sources, the source map and the output file.
+  -o, --output                  Output file (default STDOUT).
+  -b, --beautify                Beautify output/specify output options.
+  -m, --mangle                  Mangle names/pass mangler options.
+  -r, --reserved                Reserved names to exclude from mangling.
+  -c, --compress                Enable compressor/pass compressor options, e.g.
+                                `-c 'if_return=false,pure_funcs=["Math.pow","console.log"]'`
+                                Use `-c` with no argument to enable default compression
+                                options.
+  -d, --define                  Global definitions
+  -e, --enclose                 Embed everything in a big function, with a
+                                configurable parameter/argument list.
+  --comments                    Preserve copyright comments in the output. By
+                                default this works like Google Closure, keeping
+                                JSDoc-style comments that contain "@license" or
+                                "@preserve". You can optionally pass one of the
+                                following arguments to this flag:
+                                - "all" to keep all comments
+                                - a valid JS RegExp like `/foo/` or `/^!/` to
+                                keep only matching comments.
+                                Note that currently not *all* comments can be
+                                kept when compression is on, because of dead
+                                code removal or cascading statements into
+                                sequences.
+  --preamble                    Preamble to prepend to the output.  You can use
+                                this to insert a comment, for example for
+                                licensing information.  This will not be
+                                parsed, but the source map will adjust for its
+                                presence.
+  --stats                       Display operations run time on STDERR.
+  --acorn                       Use Acorn for parsing.
+  --spidermonkey                Assume input files are SpiderMonkey AST format
+                                (as JSON).
+  --self                        Build itself (UglifyJS2) as a library (implies
+                                --wrap=UglifyJS --export-all)
+  --wrap                        Embed everything in a big function, making the
+                                “exports” and “global” variables available. You
+                                need to pass an argument to this option to
+                                specify the name that your module will take
+                                when included in, say, a browser.
+  --export-all                  Only used when --wrap, this tells UglifyJS to
+                                add code to automatically export all globals.
+  --lint                        Display some scope warnings
+  -v, --verbose                 Verbose
+  -V, --version                 Print version number and exit.
+  --noerr                       Don't throw an error for unknown options in -c,
+                                -b or -m.
+  --bare-returns                Allow return outside of functions.  Useful when
+                                minifying CommonJS modules and Userscripts that
+                                may be anonymous function wrapped (IIFE) by the
+                                .user.js engine `caller`.
+  --keep-fnames                 Do not mangle/drop function names.  Useful for
+                                code relying on Function.prototype.name.
+  --reserved-file               File containing reserved names
+  --reserve-domprops            Make (most?) DOM properties reserved for
+                                --mangle-props
+  --mangle-props                Mangle property names (default `0`). Set to
+                                `true` or `1` to mangle all property names. Set
+                                to `unquoted` or `2` to only mangle unquoted
+                                property names. Mode `2` also enables the
+                                `keep_quoted_props` beautifier option to
+                                preserve the quotes around property names and
+                                disables the `properties` compressor option to
+                                prevent rewriting quoted properties with dot
+                                notation. You can override these by setting
+                                them explicitly on the command line.
+  --mangle-regex                Only mangle property names matching the regex
+  --name-cache                  File to hold mangled names mappings
+  --pure-funcs                  Functions that can be safely removed if their
+                                return value is not used, e.g.
+                                `--pure-funcs Math.floor console.info`
+                                (requires `--compress`)
+```
 
 Specify `--output` (`-o`) to declare the output file.  Otherwise the output
 goes to STDOUT.
@@ -138,24 +201,20 @@ compressed JS by mapping every token in the compiled JS to its original
 location.
 
 To use this feature you need to pass `--in-source-map
-/path/to/input/source.map`.  Normally the input source map should also point
-to the file containing the generated JS, so if that's correct you can omit
-input files from the command line.
+/path/to/input/source.map` or `--in-source-map inline` if the source map is
+included inline with the sources. Normally the input source map should also
+point to the file containing the generated JS, so if that's correct you can
+omit input files from the command line.
 
 ## Mangler options
 
 To enable the mangler you need to pass `--mangle` (`-m`).  The following
 (comma-separated) options are supported:
 
-- `sort` — to assign shorter names to most frequently used variables.  This
-  saves a few hundred bytes on jQuery before gzip, but the output is
-  _bigger_ after gzip (and seems to happen for other libraries I tried it
-  on) therefore it's not enabled by default.
-
 - `toplevel` — mangle names declared in the toplevel scope (disabled by
   default).
 
-- `eval` — mangle names visible in scopes where `eval` or `when` are used
+- `eval` — mangle names visible in scopes where `eval` or `with` are used
   (disabled by default).
 
 When mangling is enabled but you want to prevent certain names from being
@@ -166,6 +225,99 @@ comma-separated list of names.  For example:
 
 to prevent the `require`, `exports` and `$` names from being changed.
 
+### Mangling property names (`--mangle-props`)
+
+**Note:** this will probably break your code.  Mangling property names is a
+separate step, different from variable name mangling.  Pass
+`--mangle-props`.  It will mangle all properties that are seen in some
+object literal, or that are assigned to.  For example:
+
+```js
+var x = {
+  foo: 1
+};
+
+x.bar = 2;
+x["baz"] = 3;
+x[condition ? "moo" : "boo"] = 4;
+console.log(x.something());
+```
+
+In the above code, `foo`, `bar`, `baz`, `moo` and `boo` will be replaced
+with single characters, while `something()` will be left as is.
+
+In order for this to be of any use, we should avoid mangling standard JS
+names.  For instance, if your code would contain `x.length = 10`, then
+`length` becomes a candidate for mangling and it will be mangled throughout
+the code, regardless if it's being used as part of your own objects or
+accessing an array's length.  To avoid that, you can use `--reserved-file`
+to pass a filename that should contain the names to be excluded from
+mangling.  This file can be used both for excluding variable names and
+property names.  It could look like this, for example:
+
+```js
+{
+  "vars": [ "define", "require", ... ],
+  "props": [ "length", "prototype", ... ]
+}
+```
+
+`--reserved-file` can be an array of file names (either a single
+comma-separated argument, or you can pass multiple `--reserved-file`
+arguments) — in this case it will exclude names from all those files.
+
+A default exclusion file is provided in `tools/domprops.json` which should
+cover most standard JS and DOM properties defined in various browsers.  Pass
+`--reserve-domprops` to read that in.
+
+You can also use a regular expression to define which property names should be
+mangled.  For example, `--mangle-regex="/^_/"` will only mangle property names
+that start with an underscore.
+
+When you compress multiple files using this option, in order for them to
+work together in the end we need to ensure somehow that one property gets
+mangled to the same name in all of them.  For this, pass `--name-cache
+filename.json` and UglifyJS will maintain these mappings in a file which can
+then be reused.  It should be initially empty.  Example:
+
+```
+rm -f /tmp/cache.json  # start fresh
+uglifyjs file1.js file2.js --mangle-props --name-cache /tmp/cache.json -o part1.js
+uglifyjs file3.js file4.js --mangle-props --name-cache /tmp/cache.json -o part2.js
+```
+
+Now, `part1.js` and `part2.js` will be consistent with each other in terms
+of mangled property names.
+
+Using the name cache is not necessary if you compress all your files in a
+single call to UglifyJS.
+
+#### Mangling unquoted names (`--mangle-props=unquoted` or `--mangle-props=2`)
+
+Using quoted property name (`o["foo"]`) reserves the property name (`foo`)
+so that it is not mangled throughout the entire script even when used in an
+unquoted style (`o.foo`). Example:
+
+```
+$ echo 'var o={"foo":1, bar:3}; o.foo += o.bar; console.log(o.foo);' | uglifyjs --mangle-props=2 -mc
+var o={"foo":1,a:3};o.foo+=o.a,console.log(o.foo);
+```
+
+#### Debugging property name mangling
+
+You can also pass `--mangle-props-debug` in order to mangle property names
+without completely obscuring them. For example the property `o.foo`
+would mangle to `o._$foo$_` with this option. This allows property mangling
+of a large codebase while still being able to debug the code and identify
+where mangling is breaking things.
+
+You can also pass a custom suffix using `--mangle-props-debug=XYZ`. This would then
+mangle `o.foo` to `o._$foo$XYZ_`. You can change this each time you compile a
+script to identify how a property got mangled. One technique is to pass a
+random number on every compile to simulate mangling changing with different
+inputs (e.g. as you update the input script with new properties), and to help
+identify mistakes like writing mangled keys to storage.
+
 ## Compressor options
 
 You need to pass `--compress` (`-c`) to enable the compressor.  Optionally
@@ -173,33 +325,122 @@ you can pass a comma-separated list of options.  Options are in the form
 `foo=bar`, or just `foo` (the latter implies a boolean option that you want
 to set `true`; it's effectively a shortcut for `foo=true`).
 
-- `sequences` -- join consecutive simple statements using the comma operator
+- `sequences` (default: true) -- join consecutive simple statements using the
+  comma operator.  May be set to a positive integer to specify the maximum number
+  of consecutive comma sequences that will be generated. If this option is set to
+  `true` then the default `sequences` limit is `200`. Set option to `false` or `0`
+  to disable. The smallest `sequences` length is `2`. A `sequences` value of `1`
+  is grandfathered to be equivalent to `true` and as such means `200`. On rare
+  occasions the default sequences limit leads to very slow compress times in which
+  case a value of `20` or less is recommended.
+
 - `properties` -- rewrite property access using the dot notation, for
   example `foo["bar"] → foo.bar`
+
 - `dead_code` -- remove unreachable code
+
 - `drop_debugger` -- remove `debugger;` statements
+
 - `unsafe` (default: false) -- apply "unsafe" transformations (discussion below)
+
+- `unsafe_comps` (default: false) -- Reverse `<` and `<=` to `>` and `>=` to
+  allow improved compression. This might be unsafe when an at least one of two
+  operands is an object with computed values due the use of methods like `get`,
+  or `valueOf`. This could cause change in execution order after operands in the
+  comparison are switching. Compression only works if both `comparisons` and
+  `unsafe_comps` are both set to true.
+
+- `unsafe_math` (default: false) -- optimize numerical expressions like
+  `2 * x * 3` into `6 * x`, which may give imprecise floating point results.
+
+- `unsafe_proto` (default: false) -- optimize expressions like
+  `Array.prototype.slice.call(a)` into `[].slice.call(a)`
+
 - `conditionals` -- apply optimizations for `if`-s and conditional
   expressions
+
 - `comparisons` -- apply certain optimizations to binary nodes, for example:
-  `!(a <= b) → a > b` (only when `unsafe`), attempts to negate binary nodes,
-  e.g. `a = !b && !c && !d && !e → a=!(b||c||d||e)` etc.
+  `!(a <= b) → a > b` (only when `unsafe_comps`), attempts to negate binary
+  nodes, e.g. `a = !b && !c && !d && !e → a=!(b||c||d||e)` etc.
+
 - `evaluate` -- attempt to evaluate constant expressions
+
 - `booleans` -- various optimizations for boolean context, for example `!!a
   ? b : c → a ? b : c`
+
 - `loops` -- optimizations for `do`, `while` and `for` loops when we can
   statically determine the condition
-- `unused` -- drop unreferenced functions and variables
+
+- `unused` -- drop unreferenced functions and variables (simple direct variable
+  assignments do not count as references unless set to `"keep_assign"`)
+
+- `toplevel` -- drop unreferenced functions (`"funcs"`) and/or variables (`"vars"`)
+  in the toplevel scope (`false` by default, `true` to drop both unreferenced
+  functions and variables)
+
+- `top_retain` -- prevent specific toplevel functions and variables from `unused`
+  removal (can be array, comma-separated, RegExp or function. Implies `toplevel`)
+
 - `hoist_funs` -- hoist function declarations
+
 - `hoist_vars` (default: false) -- hoist `var` declarations (this is `false`
   by default because it seems to increase the size of the output in general)
+
 - `if_return` -- optimizations for if/return and if/continue
+
 - `join_vars` -- join consecutive `var` statements
+
 - `cascade` -- small optimization for sequences, transform `x, x` into `x`
   and `x = something(), x` into `x = something()`
+
+- `collapse_vars` -- Collapse single-use `var` and `const` definitions
+  when possible.
+
+- `reduce_vars` -- Improve optimization on variables assigned with and
+  used as constant values.
+
 - `warnings` -- display warnings when dropping unreachable code or unused
   declarations etc.
 
+- `negate_iife` -- negate "Immediately-Called Function Expressions"
+  where the return value is discarded, to avoid the parens that the
+  code generator would insert.
+
+- `pure_getters` -- the default is `false`.  If you pass `true` for
+  this, UglifyJS will assume that object property access
+  (e.g. `foo.bar` or `foo["bar"]`) doesn't have any side effects.
+
+- `pure_funcs` -- default `null`.  You can pass an array of names and
+  UglifyJS will assume that those functions do not produce side
+  effects.  DANGER: will not check if the name is redefined in scope.
+  An example case here, for instance `var q = Math.floor(a/b)`.  If
+  variable `q` is not used elsewhere, UglifyJS will drop it, but will
+  still keep the `Math.floor(a/b)`, not knowing what it does.  You can
+  pass `pure_funcs: [ 'Math.floor' ]` to let it know that this
+  function won't produce any side effect, in which case the whole
+  statement would get discarded.  The current implementation adds some
+  overhead (compression will be slower).
+
+- `drop_console` -- default `false`.  Pass `true` to discard calls to
+  `console.*` functions. If you wish to drop a specific function call
+  such as `console.info` and/or retain side effects from function arguments
+  after dropping the function call then use `pure_funcs` instead.
+
+- `expression` -- default `false`.  Pass `true` to preserve completion values
+  from terminal statements without `return`, e.g. in bookmarklets.
+
+- `keep_fargs` -- default `true`.  Prevents the
+  compressor from discarding unused function arguments.  You need this
+  for code which relies on `Function.length`.
+
+- `keep_fnames` -- default `false`.  Pass `true` to prevent the
+  compressor from discarding function names.  Useful for code relying on
+  `Function.prototype.name`. See also: the `keep_fnames` [mangle option](#mangle).
+
+- `passes` -- default `1`. Number of times to run compress. Use an
+  integer argument larger than 1 to further reduce code size in some cases.
+  Note: raising the number of passes will increase uglify compress time.
+
 ### The `unsafe` option
 
 It enables some transformations that *might* break code logic in certain
@@ -207,14 +448,14 @@ contrived cases, but should be fine for most code.  You might want to try it
 on your own code, it should reduce the minified size.  Here's what happens
 when this flag is on:
 
-- `new Array(1, 2, 3)` or `Array(1, 2, 3)` → `[1, 2, 3 ]`
+- `new Array(1, 2, 3)` or `Array(1, 2, 3)` → `[ 1, 2, 3 ]`
 - `new Object()` → `{}`
 - `String(exp)` or `exp.toString()` → `"" + exp`
 - `new Object/RegExp/Function/Error/Array (...)` → we discard the `new`
 - `typeof foo == "undefined"` → `foo === void 0`
-- `void 0` → `"undefined"` (if there is a variable named "undefined" in
+- `void 0` → `undefined` (if there is a variable named "undefined" in
   scope; we do it because the variable name will be mangled, typically
-  reduced to a single character).
+  reduced to a single character)
 
 ### Conditional compilation
 
@@ -228,6 +469,8 @@ if (DEBUG) {
 }
 ```
 
+You can specify nested constants in the form of `--define env.DEBUG=false`.
+
 UglifyJS will warn about the condition being always false and about dropping
 unreachable code; for now there is no option to turn off only this specific
 warning, you can pass `warnings=false` to turn off *all* warnings.
@@ -247,10 +490,27 @@ and build your code like this:
 
 UglifyJS will notice the constants and, since they cannot be altered, it
 will evaluate references to them to the value itself and drop unreachable
-code as usual.  The possible downside of this approach is that the build
-will contain the `const` declarations.
+code as usual.  The build will contain the `const` declarations if you use
+them. If you are targeting < ES6 environments which does not support `const`,
+using `var` with `reduce_vars` (enabled by default) should suffice.
 
 <a name="codegen-options"></a>
+
+#### Conditional compilation, API
+You can also use conditional compilation via the programmatic API. With the difference that the
+property name is `global_defs` and is a compressor property:
+
+```js
+uglifyJS.minify([ "input.js"], {
+    compress: {
+        dead_code: true,
+        global_defs: {
+            DEBUG: false
+        }
+    }
+});
+```
+
 ## Beautifier options
 
 The code generator tries to output shortest code possible by default.  In
@@ -267,7 +527,7 @@ can pass additional arguments that control the code output:
   objects
 - `space-colon` (default `true`) -- insert a space after the colon signs
 - `ascii-only` (default `false`) -- escape Unicode characters in strings and
-  regexps
+  regexps (affects directives with non-ascii characters becoming invalid)
 - `inline-script` (default `false`) -- escape the slash in occurrences of
   `</script` in strings
 - `width` (default 80) -- only takes effect when beautification is on, this
@@ -276,9 +536,6 @@ can pass additional arguments that control the code output:
   It doesn't work very well currently, but it does make the code generated
   by UglifyJS more readable.
 - `max-line-len` (default 32000) -- maximum line length (for uglified code)
-- `ie-proof` (default `true`) -- generate “IE-proof” code (for now this
-  means add brackets around the do/while in code like this: `if (foo) do
-  something(); while (bar); else ...`.
 - `bracketize` (default `false`) -- always insert brackets in `if`, `for`,
   `do`, `while` or `with` statements, even if their body is a single
   statement.
@@ -286,6 +543,22 @@ can pass additional arguments that control the code output:
   you pass `false` then whenever possible we will use a newline instead of a
   semicolon, leading to more readable output of uglified code (size before
   gzip could be smaller; size after gzip insignificantly larger).
+- `preamble` (default `null`) -- when passed it must be a string and
+  it will be prepended to the output literally.  The source map will
+  adjust for this text.  Can be used to insert a comment containing
+  licensing information, for example.
+- `quote_style` (default `0`) -- preferred quote style for strings (affects
+  quoted property names and directives as well):
+  - `0` -- prefers double quotes, switches to single quotes when there are
+    more double quotes in the string itself.
+  - `1` -- always use single quotes
+  - `2` -- always use double quotes
+  - `3` -- always use the original quotes
+- `keep_quoted_props` (default `false`) -- when turned on, prevents stripping
+  quotes from property names in object literals.
+- `ecma` (default `5`) -- set output printing mode.  This will only change the
+  output in direct control of the beautifier.  Non-compatible features in the
+  abstract syntax tree will still be outputted as is.
 
 ### Keeping copyright notices or other comments
 
@@ -343,6 +616,38 @@ Acorn is really fast (e.g. 250ms instead of 380ms on some 650K code), but
 converting the SpiderMonkey tree that Acorn produces takes another 150ms so
 in total it's a bit more than just using UglifyJS's own parser.
 
+### Using UglifyJS to transform SpiderMonkey AST
+
+Now you can use UglifyJS as any other intermediate tool for transforming
+JavaScript ASTs in SpiderMonkey format.
+
+Example:
+
+```javascript
+function uglify(ast, options, mangle) {
+  // Conversion from SpiderMonkey AST to internal format
+  var uAST = UglifyJS.AST_Node.from_mozilla_ast(ast);
+
+  // Compression
+  uAST.figure_out_scope();
+  uAST = UglifyJS.Compressor(options).compress(uAST);
+
+  // Mangling (optional)
+  if (mangle) {
+    uAST.figure_out_scope();
+    uAST.compute_char_frequency();
+    uAST.mangle_names();
+  }
+
+  // Back-conversion to SpiderMonkey AST
+  return uAST.to_mozilla_ast();
+}
+```
+
+Check out
+[original blog post](http://rreverser.com/using-mozilla-ast-with-uglifyjs/)
+for details.
+
 API Reference
 -------------
 
@@ -383,9 +688,26 @@ console.log(result.code); // minified output
 console.log(result.map);
 ```
 
+To generate a source map with the fromString option, you can also use an object:
+```javascript
+var result = UglifyJS.minify({"file1.js": "var a = function () {};"}, {
+  outSourceMap: "out.js.map",
+  outFileName: "out.js",
+  fromString: true
+});
+```
+
 Note that the source map is not saved in a file, it's just returned in
-`result.map`.  The value passed for `outSourceMap` is only used to set the
-`file` attribute in the source map (see [the spec][sm-spec]).
+`result.map`.  The value passed for `outSourceMap` is only used to set
+`//# sourceMappingURL=out.js.map` in `result.code`. The value of
+`outFileName` is only used to set `file` attribute in source map file.
+
+The `file` attribute in the source map (see [the spec][sm-spec]) will
+use `outFileName` firstly, if it's falsy, then will be deduced from
+`outSourceMap` (by removing `'.map'`).
+
+You can set option `sourceMapInline` to be `true` and source map will
+be appended to code.
 
 You can also specify sourceRoot property to be included in source map:
 ```javascript
@@ -405,9 +727,30 @@ var result = UglifyJS.minify("compiled.js", {
 // same as before, it returns `code` and `map`
 ```
 
+If your input source map is not in a file, you can pass it in as an object
+using the `inSourceMap` argument:
+
+```javascript
+var result = UglifyJS.minify("compiled.js", {
+	inSourceMap: JSON.parse(my_source_map_string),
+	outSourceMap: "minified.js.map"
+});
+```
+
 The `inSourceMap` is only used if you also request `outSourceMap` (it makes
 no sense otherwise).
 
+To set the source map url, use the `sourceMapUrl` option.
+If you're using the X-SourceMap header instead, you can just set the `sourceMapUrl` option to false.
+Defaults to outSourceMap:
+
+```javascript
+var result = UglifyJS.minify([ "file1.js" ], {
+  outSourceMap: "out.js.map",
+  sourceMapUrl: "localhost/out.js.map"
+});
+```
+
 Other options:
 
 - `warnings` (default `false`) — pass `true` to display compressor warnings.
@@ -415,7 +758,11 @@ Other options:
 - `fromString` (default `false`) — if you pass `true` then you can pass
   JavaScript source code, rather than file names.
 
-- `mangle` — pass `false` to skip mangling names.
+- `mangle` (default `true`) — pass `false` to skip mangling names, or pass
+  an object to specify mangling options (see below).
+
+- `mangleProperties` (default `false`) — pass an object to specify custom
+  mangle property options.
 
 - `output` (default `null`) — pass an object if you wish to specify
   additional [output options][codegen].  The defaults are optimized
@@ -424,6 +771,49 @@ Other options:
 - `compress` (default `{}`) — pass `false` to skip compressing entirely.
   Pass an object to specify custom [compressor options][compressor].
 
+- `parse` (default {}) — pass an object if you wish to specify some
+  additional [parser options][parser]. (not all options available... see below)
+
+##### mangle
+
+ - `except` - pass an array of identifiers that should be excluded from mangling
+
+ - `toplevel` — mangle names declared in the toplevel scope (disabled by
+  default).
+
+ - `eval` — mangle names visible in scopes where eval or with are used
+  (disabled by default).
+
+ - `keep_fnames` -- default `false`.  Pass `true` to not mangle
+  function names.  Useful for code relying on `Function.prototype.name`.
+  See also: the `keep_fnames` [compress option](#compressor-options).
+
+  Examples:
+
+  ```javascript
+  //tst.js
+  var globalVar;
+  function funcName(firstLongName, anotherLongName)
+  {
+    var myVariable = firstLongName +  anotherLongName;
+  }
+
+  UglifyJS.minify("tst.js").code;
+  // 'function funcName(a,n){}var globalVar;'
+
+  UglifyJS.minify("tst.js", { mangle: { except: ['firstLongName'] } }).code;
+  // 'function funcName(firstLongName,a){}var globalVar;'
+
+  UglifyJS.minify("tst.js", { mangle: { toplevel: true } }).code;
+  // 'function n(n,a){}var a;'
+  ```
+
+##### mangleProperties options
+
+ - `regex` — Pass a RegExp to only mangle certain names (maps to the `--mangle-regex` CLI arguments option)
+ - `ignore_quoted` – Only mangle unquoted property names (maps to the `--mangle-props 2` CLI arguments option)
+ - `debug` – Mangle names with the original name still present (maps to the `--mangle-props-debug` CLI arguments option). Defaults to `false`. Pass an empty string to enable, or a non-empty string to set the suffix.
+
 We could add more options to `UglifyJS.minify` — if you need additional
 functionality please suggest!
 
@@ -442,6 +832,9 @@ properties are available:
 
 - `strict` — disable automatic semicolon insertion and support for trailing
   comma in arrays and objects
+- `bare_returns` — Allow return outside of functions. (maps to the
+  `--bare-returns` CLI arguments option and available to `minify` `parse`
+  other options object)
 - `filename` — the name of the file where this code is coming from
 - `toplevel` — a `toplevel` node (as returned by a previous invocation of
   `parse`)
@@ -452,7 +845,7 @@ something like this:
 ```javascript
 var toplevel = null;
 files.forEach(function(file){
-	var code = fs.readFileSync(file);
+	var code = fs.readFileSync(file, "utf8");
 	toplevel = UglifyJS.parse(code, {
 		filename: file,
 		toplevel: toplevel
@@ -481,7 +874,7 @@ toplevel.figure_out_scope()
 Like this:
 ```javascript
 var compressor = UglifyJS.Compressor(options);
-var compressed_ast = toplevel.transform(compressor);
+var compressed_ast = compressor.compress(toplevel);
 ```
 
 The `options` can be missing.  Available options are discussed above in
@@ -519,15 +912,18 @@ or, for a shortcut you can do:
 var code = compressed_ast.print_to_string(options);
 ```
 
-As usual, `options` is optional.  The output stream accepts a lot of otions,
+As usual, `options` is optional.  The output stream accepts a lot of options,
 most of them documented above in section “Beautifier options”.  The two
 which we care about here are `source_map` and `comments`.
 
 #### Keeping comments in the output
 
 In order to keep certain comments in the output you need to pass the
-`comments` option.  Pass a RegExp or a function.  If you pass a RegExp, only
-those comments whose body matches the regexp will be kept.  Note that body
+`comments` option.  Pass a RegExp (as string starting and closing with `/`
+or pass a RegExp object), a boolean or a function.  Stringified options
+`all` and `some` can be passed too, where `some` behaves like it's cli
+equivalent `--comments` without passing a value. If you pass a RegExp,
+only those comments whose body matches the RegExp will be kept.  Note that body
 means without the initial `//` or `/*`.  If you pass a function, it will be
 called for every comment in the tree and will receive two arguments: the
 node that the comment is attached to, and the comment token itself.
@@ -576,8 +972,26 @@ The `source_map_options` (optional) can contain the following properties:
   came from.  It can be simply a string in JSON, or a JSON object containing
   the original source map.
 
-  [acorn]: https://github.com/marijnh/acorn
+  [acorn]: https://github.com/ternjs/acorn
   [source-map]: https://github.com/mozilla/source-map
   [sm-spec]: https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k/edit
   [codegen]: http://lisperator.net/uglifyjs/codegen
   [compressor]: http://lisperator.net/uglifyjs/compress
+  [parser]: http://lisperator.net/uglifyjs/parser
+
+#### Harmony
+
+If you wish to use the experimental [harmony](https://github.com/mishoo/UglifyJS2/commits/harmony)
+branch to minify ES2015+ (ES6+) code please use the following in your `package.json` file:
+
+```
+"uglify-js": "git+https://github.com/mishoo/UglifyJS2.git#harmony"
+```
+
+or to directly install the experimental harmony version of uglify:
+
+```
+npm install --save-dev uglify-js@github:mishoo/UglifyJS2#harmony
+```
+
+See [#448](https://github.com/mishoo/UglifyJS2/issues/448) for additional details.

appveyor.yml

@@ -0,0 +1,24 @@
+environment:
+  matrix:
+  - nodejs_version: "0.10"
+  - nodejs_version: "0.12"
+  - nodejs_version: "4.0"
+  - nodejs_version: "6.0"
+
+matrix:
+  fast_finish: true
+
+platform:
+  - x86
+  - x64
+
+install:
+  - ps: Install-Product node $env:nodejs_version $env:platform
+  - npm install
+
+test_script:
+  - node --version
+  - npm --version
+  - npm test
+
+build: off

bin/extract-props.js

@@ -0,0 +1,77 @@
+#! /usr/bin/env node
+
+"use strict";
+
+var U2 = require("../tools/node");
+var fs = require("fs");
+var yargs = require("yargs");
+var ARGS = yargs
+    .describe("o", "Output file")
+    .argv;
+var files = ARGS._.slice();
+var output = {
+    vars: {},
+    props: {}
+};
+
+if (ARGS.o) try {
+    output = JSON.parse(fs.readFileSync(ARGS.o, "utf8"));
+} catch(ex) {}
+
+files.forEach(getProps);
+
+if (ARGS.o) {
+    fs.writeFileSync(ARGS.o, JSON.stringify(output, null, 2), "utf8");
+} else {
+    console.log("%s", JSON.stringify(output, null, 2));
+}
+
+function getProps(filename) {
+    var code = fs.readFileSync(filename, "utf8");
+    var ast = U2.parse(code);
+
+    ast.walk(new U2.TreeWalker(function(node){
+        if (node instanceof U2.AST_ObjectKeyVal) {
+            add(node.key);
+        }
+        else if (node instanceof U2.AST_ObjectProperty) {
+            add(node.key.name);
+        }
+        else if (node instanceof U2.AST_Dot) {
+            add(node.property);
+        }
+        else if (node instanceof U2.AST_Sub) {
+            addStrings(node.property);
+        }
+    }));
+
+    function addStrings(node) {
+        var out = {};
+        try {
+            (function walk(node){
+                node.walk(new U2.TreeWalker(function(node){
+                    if (node instanceof U2.AST_Seq) {
+                        walk(node.cdr);
+                        return true;
+                    }
+                    if (node instanceof U2.AST_String) {
+                        add(node.value);
+                        return true;
+                    }
+                    if (node instanceof U2.AST_Conditional) {
+                        walk(node.consequent);
+                        walk(node.alternative);
+                        return true;
+                    }
+                    throw out;
+                }));
+            })(node);
+        } catch(ex) {
+            if (ex !== out) throw ex;
+        }
+    }
+
+    function add(name) {
+        output.props[name] = true;
+    }
+}

bin/uglifyjs

@@ -5,11 +5,12 @@
 
 var UglifyJS = require("../tools/node");
 var sys = require("util");
-var optimist = require("optimist");
+var yargs = require("yargs");
 var fs = require("fs");
-var async = require("async");
+var path = require("path");
 var acorn;
-var ARGS = optimist
+var screw_ie8 = true;
+var ARGS = yargs
     .usage("$0 input1.js [input2.js ...] [options]\n\
 Use a single dash to read input from the standard input.\
 \n\n\
@@ -20,11 +21,17 @@ mangling you need to use `-c` and `-m`.\
 ")
     .describe("source-map", "Specify an output file where to generate source map.")
     .describe("source-map-root", "The path to the original source to be included in the source map.")
-    .describe("source-map-url", "The path to the source map to be added in //@ sourceMappingURL.  Defaults to the value passed with --source-map.")
+    .describe("source-map-url", "The path to the source map to be added in //# sourceMappingURL.  Defaults to the value passed with --source-map.")
+    .describe("source-map-inline", "Write base64-encoded source map to the end of js output.  Disabled by default")
+    .describe("source-map-include-sources", "Pass this flag if you want to include the content of source files in the source map as sourcesContent property.")
     .describe("in-source-map", "Input source map, useful if you're compressing JS that was generated from some other original code.")
-    .describe("screw-ie8", "Pass this flag if you don't care about full compliance with Internet Explorer 6-8 quirks (by default UglifyJS will try to be IE-proof).")
+    .describe("screw-ie8", "Do not support Internet Explorer 6/7/8. This flag is enabled by default.")
+    .describe("support-ie8", "Support non-standard Internet Explorer 6/7/8 javascript.")
+    .describe("expr", "Parse a single expression, rather than a program (for parsing JSON)")
     .describe("p", "Skip prefix for original filenames that appear in source maps. \
-For example -p 3 will drop 3 directories from file names and ensure they are relative paths.")
+For example -p 3 will drop 3 directories from file names and ensure they are relative paths. \
+You can also specify -p relative, which will make UglifyJS figure out itself the relative paths between original sources, \
+the source map and the output file.")
     .describe("o", "Output file (default STDOUT).")
     .describe("b", "Beautify output/specify output options.")
     .describe("m", "Mangle names/pass mangler options.")
@@ -39,11 +46,15 @@ Use -c with no argument to use the default compression options.")
 By default this works like Google Closure, keeping JSDoc-style comments that contain \"@license\" or \"@preserve\". \
 You can optionally pass one of the following arguments to this flag:\n\
 - \"all\" to keep all comments\n\
-- a valid JS regexp (needs to start with a slash) to keep only comments that match.\n\
+- a valid JS RegExp like `/foo/`or `/^!/` to keep only matching comments.\n\
 \
 Note that currently not *all* comments can be kept when compression is on, \
 because of dead code removal or cascading statements into sequences.")
 
+    .describe("preamble", "Preamble to prepend to the output.  You can use this to insert a \
+comment, for example for licensing information.  This will not be \
+parsed, but the source map will adjust for its presence.")
+
     .describe("stats", "Display operations run time on STDERR.")
     .describe("acorn", "Use Acorn for parsing.")
     .describe("spidermonkey", "Assume input files are SpiderMonkey AST format (as JSON).")
@@ -54,6 +65,18 @@ You need to pass an argument to this option to specify the name that your module
     .describe("lint", "Display some scope warnings")
     .describe("v", "Verbose")
     .describe("V", "Print version number and exit.")
+    .describe("noerr", "Don't throw an error for unknown options in -c, -b or -m.")
+    .describe("bare-returns", "Allow return outside of functions.  Useful when minifying CommonJS modules.")
+    .describe("keep-fnames", "Do not mangle/drop function names.  Useful for code relying on Function.prototype.name.")
+    .describe("quotes", "Quote style (0 - auto, 1 - single, 2 - double, 3 - original)")
+    .describe("reserved-file", "File containing reserved names")
+    .describe("reserve-domprops", "Make (most?) DOM properties reserved for --mangle-props")
+    .describe("mangle-props", "Mangle property names (0 - disabled, 1 - mangle all properties, 2 - mangle unquoted properies)")
+    .describe("mangle-regex", "Only mangle property names matching the regex")
+    .describe("name-cache", "File to hold mangled names mappings")
+    .describe("pure-funcs", "List of functions that can be safely removed if their return value is not used")
+    .describe("dump-spidermonkey-ast", "Dump SpiderMonkey AST to stdout.")
+    .describe("wrap-iife", "Wrap IIFEs in parenthesis. Note: this disables the negate_iife compression option")
 
     .alias("p", "prefix")
     .alias("o", "output")
@@ -65,26 +88,52 @@ You need to pass an argument to this option to specify the name that your module
     .alias("r", "reserved")
     .alias("V", "version")
     .alias("e", "enclose")
+    .alias("q", "quotes")
 
     .string("source-map")
     .string("source-map-root")
     .string("source-map-url")
     .string("b")
+    .string("beautify")
     .string("m")
+    .string("mangle")
+    .string("mangle-props-debug")
     .string("c")
+    .string("compress")
     .string("d")
+    .string("define")
     .string("e")
+    .string("enclose")
     .string("comments")
     .string("wrap")
+    .string("p")
+    .string("prefix")
+    .string("name-cache")
+
+    .array("reserved-file")
+    .array("pure-funcs")
+
+    .boolean("expr")
+    .boolean("source-map-inline")
+    .boolean("source-map-include-sources")
     .boolean("screw-ie8")
+    .boolean("support-ie8")
     .boolean("export-all")
     .boolean("self")
     .boolean("v")
+    .boolean("verbose")
     .boolean("stats")
     .boolean("acorn")
     .boolean("spidermonkey")
+    .boolean("dump-spidermonkey-ast")
     .boolean("lint")
     .boolean("V")
+    .boolean("version")
+    .boolean("noerr")
+    .boolean("bare-returns")
+    .boolean("keep-fnames")
+    .boolean("reserve-domprops")
+    .boolean("wrap-iife")
 
     .wrap(80)
 
@@ -93,20 +142,26 @@ You need to pass an argument to this option to specify the name that your module
 
 normalize(ARGS);
 
+if (ARGS.noerr) {
+    UglifyJS.DefaultsError.croak = function(msg, defs) {
+        print_error("WARN: " + msg);
+    };
+}
+
 if (ARGS.version || ARGS.V) {
     var json = require("../package.json");
-    sys.puts(json.name + ' ' + json.version);
+    print(json.name + ' ' + json.version);
     process.exit(0);
 }
 
 if (ARGS.ast_help) {
     var desc = UglifyJS.describe_ast();
-    sys.puts(typeof desc == "string" ? desc : JSON.stringify(desc, null, 2));
+    print(typeof desc == "string" ? desc : JSON.stringify(desc, null, 2));
     process.exit(0);
 }
 
 if (ARGS.h || ARGS.help) {
-    sys.puts(optimist.help());
+    print(yargs.help());
     process.exit(0);
 }
 
@@ -117,115 +172,176 @@ if (ARGS.acorn) {
 var COMPRESS = getOptions("c", true);
 var MANGLE = getOptions("m", true);
 var BEAUTIFY = getOptions("b", true);
+var RESERVED = null;
+
+if (ARGS.reserved_file) ARGS.reserved_file.forEach(function(filename){
+    RESERVED = UglifyJS.readReservedFile(filename, RESERVED);
+});
+
+if (ARGS.reserve_domprops) {
+    RESERVED = UglifyJS.readDefaultReservedFile(RESERVED);
+}
 
 if (ARGS.d) {
     if (COMPRESS) COMPRESS.global_defs = getOptions("d");
 }
 
-if (ARGS.screw_ie8) {
-    if (COMPRESS) COMPRESS.screw_ie8 = true;
-    if (MANGLE) MANGLE.screw_ie8 = true;
+if (ARGS.pure_funcs) {
+    if (COMPRESS) COMPRESS.pure_funcs = ARGS.pure_funcs;
 }
 
 if (ARGS.r) {
     if (MANGLE) MANGLE.except = ARGS.r.replace(/^\s+|\s+$/g).split(/\s*,+\s*/);
 }
 
+if (RESERVED && MANGLE) {
+    if (!MANGLE.except) MANGLE.except = RESERVED.vars;
+    else MANGLE.except = MANGLE.except.concat(RESERVED.vars);
+}
+
+function readNameCache(key) {
+    return UglifyJS.readNameCache(ARGS.name_cache, key);
+}
+
+function writeNameCache(key, cache) {
+    return UglifyJS.writeNameCache(ARGS.name_cache, key, cache);
+}
+
+function extractRegex(str) {
+  if (/^\/.*\/[a-zA-Z]*$/.test(str)) {
+    var regex_pos = str.lastIndexOf("/");
+    return new RegExp(str.substr(1, regex_pos - 1), str.substr(regex_pos + 1));
+  } else {
+    throw new Error("Invalid regular expression: " + str);
+  }
+}
+
+if (ARGS.quotes === true) {
+    ARGS.quotes = 3;
+}
+
+if (ARGS.mangle_props === true) {
+    ARGS.mangle_props = 1;
+} else if (ARGS.mangle_props === "unquoted") {
+    ARGS.mangle_props = 2;
+}
+
 var OUTPUT_OPTIONS = {
-    beautify: BEAUTIFY ? true : false
+    beautify     : BEAUTIFY ? true : false,
+    max_line_len : 32000,
+    preamble     : ARGS.preamble || null,
+    quote_style  : ARGS.quotes != null ? ARGS.quotes : 0,
 };
 
+if (ARGS.mangle_props == 2) {
+    OUTPUT_OPTIONS.keep_quoted_props = true;
+    if (COMPRESS && !("properties" in COMPRESS))
+        COMPRESS.properties = false;
+}
+
+if (ARGS.support_ie8 === true && ARGS.screw_ie8 !== true) {
+    screw_ie8 = false;
+}
+
+if (COMPRESS) COMPRESS.screw_ie8 = screw_ie8;
+if (MANGLE) MANGLE.screw_ie8 = screw_ie8;
+OUTPUT_OPTIONS.screw_ie8 = screw_ie8;
+
+if (ARGS.keep_fnames) {
+    if (COMPRESS) COMPRESS.keep_fnames = true;
+    if (MANGLE) MANGLE.keep_fnames = true;
+}
+
+if (ARGS.wrap_iife) {
+    if (COMPRESS) COMPRESS.negate_iife = false;
+    OUTPUT_OPTIONS.wrap_iife = true;
+}
+
 if (BEAUTIFY)
     UglifyJS.merge(OUTPUT_OPTIONS, BEAUTIFY);
 
-if (ARGS.comments) {
-    if (/^\//.test(ARGS.comments)) {
-        OUTPUT_OPTIONS.comments = new Function("return(" + ARGS.comments + ")")();
-    } else if (ARGS.comments == "all") {
-        OUTPUT_OPTIONS.comments = true;
-    } else {
-        OUTPUT_OPTIONS.comments = function(node, comment) {
-            var text = comment.value;
-            var type = comment.type;
-            if (type == "comment2") {
-                // multiline comment
-                return /@preserve|@license|@cc_on/i.test(text);
-            }
-        }
-    }
+if (ARGS.comments === "") {
+    OUTPUT_OPTIONS.comments = "some";
+} else {
+    OUTPUT_OPTIONS.comments = ARGS.comments;
 }
 
 var files = ARGS._.slice();
 
+if (process.platform === "win32")
+    files = UglifyJS.simple_glob(files);
+
 if (ARGS.self) {
     if (files.length > 0) {
-        sys.error("WARN: Ignoring input files since --self was passed");
+        print_error("WARN: Ignoring input files since --self was passed");
     }
     files = UglifyJS.FILES;
     if (!ARGS.wrap) ARGS.wrap = "UglifyJS";
-    ARGS.export_all = true;
 }
 
 var ORIG_MAP = ARGS.in_source_map;
 
-if (ORIG_MAP) {
+if (ORIG_MAP && ORIG_MAP != "inline") {
     ORIG_MAP = JSON.parse(fs.readFileSync(ORIG_MAP));
     if (files.length == 0) {
-        sys.error("INFO: Using file from the input source map: " + ORIG_MAP.file);
+        print_error("INFO: Using file from the input source map: " + ORIG_MAP.file);
         files = [ ORIG_MAP.file ];
     }
-    if (ARGS.source_map_root == null) {
-        ARGS.source_map_root = ORIG_MAP.sourceRoot;
-    }
 }
 
 if (files.length == 0) {
     files = [ "-" ];
 }
 
-if (files.indexOf("-") >= 0 && ARGS.source_map) {
-    sys.error("ERROR: Source map doesn't work with input from STDIN");
-    process.exit(1);
-}
-
-if (files.filter(function(el){ return el == "-" }).length > 1) {
-    sys.error("ERROR: Can read a single file from STDIN (two or more dashes specified)");
-    process.exit(1);
-}
-
-var STATS = {};
-var OUTPUT_FILE = ARGS.o;
-var TOPLEVEL = null;
-
-var SOURCE_MAP = ARGS.source_map ? UglifyJS.SourceMap({
-    file: OUTPUT_FILE,
-    root: ARGS.source_map_root,
-    orig: ORIG_MAP,
-}) : null;
-
-OUTPUT_OPTIONS.source_map = SOURCE_MAP;
-
-try {
-    var output = UglifyJS.OutputStream(OUTPUT_OPTIONS);
-    var compressor = COMPRESS && UglifyJS.Compressor(COMPRESS);
-} catch(ex) {
-    if (ex instanceof UglifyJS.DefaultsError) {
-        sys.error(ex.msg);
-        sys.error("Supported options:");
-        sys.error(sys.inspect(ex.defs));
+if (ORIG_MAP == "inline") {
+    if (files.length > 1) {
+        print_error("ERROR: Inline source map only works with singular input");
+        process.exit(1);
+    }
+    if (ARGS.acorn || ARGS.spidermonkey) {
+        print_error("ERROR: Inline source map only works with built-in parser");
         process.exit(1);
     }
 }
 
-async.eachLimit(files, 1, function (file, cb) {
+if (files.indexOf("-") >= 0 && ARGS.source_map) {
+    print_error("ERROR: Source map doesn't work with input from STDIN");
+    process.exit(1);
+}
+
+if (files.filter(function(el){ return el == "-" }).length > 1) {
+    print_error("ERROR: Can read a single file from STDIN (two or more dashes specified)");
+    process.exit(1);
+}
+
+var STATS = {};
+var TOPLEVEL = null;
+var P_RELATIVE = ARGS.p && ARGS.p == "relative";
+var SOURCES_CONTENT = {};
+var index = 0;
+
+!function cb() {
+    if (index == files.length) return done();
+    var file = files[index++];
     read_whole_file(file, function (err, code) {
         if (err) {
-            sys.error("ERROR: can't read file: " + filename);
+            print_error("ERROR: can't read file: " + file);
             process.exit(1);
         }
-        if (ARGS.p != null) {
-            file = file.replace(/^\/+/, "").split(/\/+/).slice(ARGS.p).join("/");
+        if (ORIG_MAP == "inline") {
+            ORIG_MAP = read_source_map(code);
         }
+        if (ARGS.p != null) {
+            if (P_RELATIVE) {
+                file = path.relative(path.dirname(ARGS.source_map), file).replace(/\\/g, '/');
+            } else {
+                var p = parseInt(ARGS.p, 10);
+                if (!isNaN(p)) {
+                    file = file.replace(/^\/+/, "").split(/\/+/).slice(ARGS.p).join("/");
+                }
+            }
+        }
+        SOURCES_CONTENT[file] = code;
         time_it("parse", function(){
             if (ARGS.spidermonkey) {
                 var program = JSON.parse(code);
@@ -235,44 +351,119 @@ async.eachLimit(files, 1, function (file, cb) {
             else if (ARGS.acorn) {
                 TOPLEVEL = acorn.parse(code, {
                     locations     : true,
-                    trackComments : true,
                     sourceFile    : file,
                     program       : TOPLEVEL
                 });
             }
             else {
-                TOPLEVEL = UglifyJS.parse(code, {
-                    filename: file,
-                    toplevel: TOPLEVEL
-                });
+                try {
+                    TOPLEVEL = UglifyJS.parse(code, {
+                        filename     : file,
+                        toplevel     : TOPLEVEL,
+                        expression   : ARGS.expr,
+                        bare_returns : ARGS.bare_returns,
+                    });
+                } catch(ex) {
+                    if (ex instanceof UglifyJS.JS_Parse_Error) {
+                        print_error("Parse error at " + file + ":" + ex.line + "," + ex.col);
+                        var col = ex.col;
+                        var line = code.split(/\r?\n/)[ex.line - (col ? 1 : 2)];
+                        if (line) {
+                            if (col > 40) {
+                                line = line.slice(col - 40);
+                                col = 40;
+                            }
+                            if (col) {
+                                print_error(line.slice(0, 80));
+                                print_error(line.slice(0, col).replace(/\S/g, " ") + "^");
+                            } else {
+                                print_error(line.slice(-40));
+                                print_error(line.slice(-40).replace(/\S/g, " ") + "^");
+                            }
+                        }
+                        print_error(ex.stack);
+                        process.exit(1);
+                    }
+                    throw ex;
+                }
             };
         });
         cb();
     });
-}, function () {
+}();
+
+function done() {
+    var OUTPUT_FILE = ARGS.o;
+
+    var SOURCE_MAP = (ARGS.source_map || ARGS.source_map_inline) ? UglifyJS.SourceMap({
+        file: P_RELATIVE ? path.relative(path.dirname(ARGS.source_map), OUTPUT_FILE) : OUTPUT_FILE,
+        root: ARGS.source_map_root || ORIG_MAP && ORIG_MAP.sourceRoot,
+        orig: ORIG_MAP,
+    }) : null;
+
+    OUTPUT_OPTIONS.source_map = SOURCE_MAP;
+
+    try {
+        var output = UglifyJS.OutputStream(OUTPUT_OPTIONS);
+        var compressor = COMPRESS && UglifyJS.Compressor(COMPRESS);
+    } catch(ex) {
+        if (ex instanceof UglifyJS.DefaultsError) {
+            print_error(ex.message);
+            print_error("Supported options:");
+            print_error(sys.inspect(ex.defs));
+            process.exit(1);
+        }
+    }
+
     if (ARGS.acorn || ARGS.spidermonkey) time_it("convert_ast", function(){
         TOPLEVEL = UglifyJS.AST_Node.from_mozilla_ast(TOPLEVEL);
     });
 
-    if (ARGS.wrap) {
+    if (ARGS.wrap != null) {
         TOPLEVEL = TOPLEVEL.wrap_commonjs(ARGS.wrap, ARGS.export_all);
     }
 
-    if (ARGS.enclose) {
+    if (ARGS.enclose != null) {
         var arg_parameter_list = ARGS.enclose;
-
-        if (!(arg_parameter_list instanceof Array)) {
+        if (arg_parameter_list === true) {
+            arg_parameter_list = [];
+        }
+        else if (!(arg_parameter_list instanceof Array)) {
             arg_parameter_list = [arg_parameter_list];
         }
-
         TOPLEVEL = TOPLEVEL.wrap_enclose(arg_parameter_list);
     }
 
-    var SCOPE_IS_NEEDED = COMPRESS || MANGLE || ARGS.lint;
+    if (ARGS.mangle_props || ARGS.name_cache) (function(){
+        var reserved = RESERVED ? RESERVED.props : null;
+        var cache = readNameCache("props");
+        var regex;
+
+        try {
+          regex = ARGS.mangle_regex ? extractRegex(ARGS.mangle_regex) : null;
+        } catch (e) {
+            print_error("ERROR: Invalid --mangle-regex: " + e.message);
+            process.exit(1);
+        }
+
+        TOPLEVEL = UglifyJS.mangle_properties(TOPLEVEL, {
+            reserved      : reserved,
+            cache         : cache,
+            only_cache    : !ARGS.mangle_props,
+            regex         : regex,
+            ignore_quoted : ARGS.mangle_props == 2,
+            debug         : typeof ARGS.mangle_props_debug === "undefined" ? false : ARGS.mangle_props_debug
+        });
+        writeNameCache("props", cache);
+    })();
+
+    var SCOPE_IS_NEEDED = COMPRESS || MANGLE || ARGS.lint
+    var TL_CACHE = readNameCache("vars");
+    if (MANGLE) MANGLE.cache = TL_CACHE;
 
     if (SCOPE_IS_NEEDED) {
         time_it("scope", function(){
-            TOPLEVEL.figure_out_scope({ screw_ie8: ARGS.screw_ie8 });
+            TOPLEVEL.figure_out_scope(MANGLE || { screw_ie8: screw_ie8, cache: TL_CACHE });
             if (ARGS.lint) {
                 TOPLEVEL.scope_warnings();
             }
@@ -281,14 +472,14 @@ async.eachLimit(files, 1, function (file, cb) {
 
     if (COMPRESS) {
         time_it("squeeze", function(){
-            TOPLEVEL = TOPLEVEL.transform(compressor);
+            TOPLEVEL = compressor.compress(TOPLEVEL);
         });
     }
 
     if (SCOPE_IS_NEEDED) {
         time_it("scope", function(){
-            TOPLEVEL.figure_out_scope({ screw_ie8: ARGS.screw_ie8 });
-            if (MANGLE) {
+            TOPLEVEL.figure_out_scope(MANGLE || { screw_ie8: screw_ie8, cache: TL_CACHE });
+            if (MANGLE && !TL_CACHE) {
                 TOPLEVEL.compute_char_frequency(MANGLE);
             }
         });
@@ -297,36 +488,60 @@ async.eachLimit(files, 1, function (file, cb) {
     if (MANGLE) time_it("mangle", function(){
         TOPLEVEL.mangle_names(MANGLE);
     });
-    time_it("generate", function(){
-        TOPLEVEL.print(output);
-    });
 
-    output = output.get();
+    writeNameCache("vars", TL_CACHE);
 
-    if (SOURCE_MAP) {
-        fs.writeFileSync(ARGS.source_map, SOURCE_MAP, "utf8");
-        output += "\n/*\n//@ sourceMappingURL=" + (ARGS.source_map_url || ARGS.source_map) + "\n*/";
+    if (ARGS.source_map_include_sources) {
+        for (var file in SOURCES_CONTENT) {
+            if (SOURCES_CONTENT.hasOwnProperty(file)) {
+                SOURCE_MAP.get().setSourceContent(file, SOURCES_CONTENT[file]);
+            }
+        }
     }
 
-    if (OUTPUT_FILE) {
-        fs.writeFileSync(OUTPUT_FILE, output, "utf8");
+    if (ARGS.dump_spidermonkey_ast) {
+        print(JSON.stringify(TOPLEVEL.to_mozilla_ast(), null, 2));
     } else {
-        sys.print(output);
-        sys.error("\n");
+        time_it("generate", function(){
+            TOPLEVEL.print(output);
+        });
+
+        output = output.get();
+
+        if (SOURCE_MAP) {
+            if (ARGS.source_map_inline) {
+                var base64_string = new Buffer(SOURCE_MAP.toString()).toString('base64');
+                output += "\n//# sourceMappingURL=data:application/json;charset=utf-8;base64," + base64_string;
+            } else {
+                fs.writeFileSync(ARGS.source_map, SOURCE_MAP, "utf8");
+                var source_map_url = ARGS.source_map_url || (
+                    P_RELATIVE
+                        ? path.relative(path.dirname(OUTPUT_FILE), ARGS.source_map)
+                        : ARGS.source_map
+                );
+                output += "\n//# sourceMappingURL=" + source_map_url;
+            }
+        }
+
+        if (OUTPUT_FILE) {
+            fs.writeFileSync(OUTPUT_FILE, output, "utf8");
+        } else {
+            print(output);
+        }
     }
 
     if (ARGS.stats) {
-        sys.error(UglifyJS.string_template("Timing information (compressed {count} files):", {
+        print_error(UglifyJS.string_template("Timing information (compressed {count} files):", {
             count: files.length
         }));
         for (var i in STATS) if (STATS.hasOwnProperty(i)) {
-            sys.error(UglifyJS.string_template("- {name}: {time}s", {
+            print_error(UglifyJS.string_template("- {name}: {time}s", {
                 name: i,
                 time: (STATS[i] / 1000).toFixed(3)
             }));
         }
     }
-});
+}
 
 /* -----[ functions ]----- */
 
@@ -337,34 +552,39 @@ function normalize(o) {
     }
 }
 
-function getOptions(x, constants) {
-    x = ARGS[x];
-    if (!x) return null;
+function getOptions(flag, constants) {
+    var x = ARGS[flag];
+    if (x == null || x === false) return null;
     var ret = {};
-    if (x !== true) {
+    if (x !== "") {
+        if (Array.isArray(x)) x = x.map(function (v) { return "(" + v + ")"; }).join(", ");
+
         var ast;
         try {
-            ast = UglifyJS.parse(x);
+            ast = UglifyJS.parse(x, { expression: true });
         } catch(ex) {
             if (ex instanceof UglifyJS.JS_Parse_Error) {
-                sys.error("Error parsing arguments in: " + x);
+                print_error("Error parsing arguments for flag `" + flag + "': " + x);
                 process.exit(1);
             }
         }
         ast.walk(new UglifyJS.TreeWalker(function(node){
-            if (node instanceof UglifyJS.AST_Toplevel) return; // descend
-            if (node instanceof UglifyJS.AST_SimpleStatement) return; // descend
             if (node instanceof UglifyJS.AST_Seq) return; // descend
             if (node instanceof UglifyJS.AST_Assign) {
-                var name = node.left.print_to_string({ beautify: false }).replace(/-/g, "_");
+                var name = node.left.print_to_string().replace(/-/g, "_");
                 var value = node.right;
                 if (constants)
                     value = new Function("return (" + value.print_to_string() + ")")();
                 ret[name] = value;
                 return true;    // no descend
             }
-            sys.error(node.TYPE)
-            sys.error("Error parsing arguments in: " + x);
+            if (node instanceof UglifyJS.AST_Symbol || node instanceof UglifyJS.AST_Binary) {
+                var name = node.print_to_string().replace(/-/g, "_");
+                ret[name] = true;
+                return true;    // no descend
+            }
+            print_error(node.TYPE)
+            print_error("Error parsing arguments for flag `" + flag + "': " + x);
             process.exit(1);
         }));
     }
@@ -386,6 +606,15 @@ function read_whole_file(filename, cb) {
     }
 }
 
+function read_source_map(code) {
+    var match = /\n\/\/# sourceMappingURL=data:application\/json(;.*?)?;base64,(.*)/.exec(code);
+    if (!match) {
+        print_error("WARN: inline source map not found");
+        return null;
+    }
+    return JSON.parse(new Buffer(match[2], "base64"));
+}
+
 function time_it(name, cont) {
     var t1 = new Date().getTime();
     var ret = cont();
@@ -396,3 +625,11 @@ function time_it(name, cont) {
     }
     return ret;
 }
+
+function print_error(msg) {
+    console.error("%s", msg);
+}
+
+function print(txt) {
+    console.log("%s", txt);
+}

lib/ast.js

@@ -71,7 +71,7 @@ function DEFNODE(type, props, methods, base) {
     if (type) {
         ctor.prototype.TYPE = ctor.TYPE = type;
     }
-    if (methods) for (i in methods) if (methods.hasOwnProperty(i)) {
+    if (methods) for (i in methods) if (HOP(methods, i)) {
         if (/^\$/.test(i)) {
             ctor[i.substr(1)] = methods[i];
         } else {
@@ -81,16 +81,30 @@ function DEFNODE(type, props, methods, base) {
     ctor.DEFMETHOD = function(name, method) {
         this.prototype[name] = method;
     };
+    if (typeof exports !== "undefined") {
+        exports["AST_" + type] = ctor;
+    }
     return ctor;
 };
 
-var AST_Token = DEFNODE("Token", "type value line col pos endpos nlb comments_before file", {
+var AST_Token = DEFNODE("Token", "type value line col pos endline endcol endpos nlb comments_before file raw", {
 }, null);
 
 var AST_Node = DEFNODE("Node", "start end", {
-    clone: function() {
+    _clone: function(deep) {
+        if (deep) {
+            var self = this.clone();
+            return self.transform(new TreeTransformer(function(node) {
+                if (node !== self) {
+                    return node.clone(true);
+                }
+            }));
+        }
         return new this.CTOR(this);
     },
+    clone: function(deep) {
+        return this._clone(deep);
+    },
     $documentation: "Base class of all AST nodes",
     $propdoc: {
         start: "[AST_Token] The first token of this node",
@@ -120,11 +134,12 @@ var AST_Debugger = DEFNODE("Debugger", null, {
     $documentation: "Represents a debugger statement",
 }, AST_Statement);
 
-var AST_Directive = DEFNODE("Directive", "value scope", {
+var AST_Directive = DEFNODE("Directive", "value scope quote", {
     $documentation: "Represents a directive, like \"use strict\";",
     $propdoc: {
         value: "[string] The value of this directive as a plain string (it's not an AST_String!)",
-        scope: "[AST_Scope/S] The scope that this directive affects"
+        scope: "[AST_Scope/S] The scope that this directive affects",
+        quote: "[string] the original quote character"
     },
 }, AST_Statement);
 
@@ -141,12 +156,13 @@ var AST_SimpleStatement = DEFNODE("SimpleStatement", "body", {
 }, AST_Statement);
 
 function walk_body(node, visitor) {
-    if (node.body instanceof AST_Statement) {
-        node.body._walk(visitor);
+    var body = node.body;
+    if (body instanceof AST_Node) {
+        body._walk(visitor);
+    }
+    else for (var i = 0, len = body.length; i < len; i++) {
+        body[i]._walk(visitor);
     }
-    else node.body.forEach(function(stat){
-        stat._walk(visitor);
-    });
 };
 
 var AST_Block = DEFNODE("Block", "body", {
@@ -194,28 +210,52 @@ var AST_LabeledStatement = DEFNODE("LabeledStatement", "label", {
             this.label._walk(visitor);
             this.body._walk(visitor);
         });
+    },
+    clone: function(deep) {
+        var node = this._clone(deep);
+        if (deep) {
+            var refs = node.label.references;
+            var label = this.label;
+            node.walk(new TreeWalker(function(node) {
+                if (node instanceof AST_LoopControl
+                    && node.label && node.label.thedef === label) {
+                    refs.push(node);
+                }
+            }));
+        }
+        return node;
     }
 }, AST_StatementWithBody);
 
+var AST_IterationStatement = DEFNODE("IterationStatement", null, {
+    $documentation: "Internal class.  All loops inherit from it."
+}, AST_StatementWithBody);
+
 var AST_DWLoop = DEFNODE("DWLoop", "condition", {
     $documentation: "Base class for do/while statements",
     $propdoc: {
         condition: "[AST_Node] the loop condition.  Should not be instanceof AST_Statement"
-    },
+    }
+}, AST_IterationStatement);
+
+var AST_Do = DEFNODE("Do", null, {
+    $documentation: "A `do` statement",
+    _walk: function(visitor) {
+        return visitor._visit(this, function(){
+            this.body._walk(visitor);
+            this.condition._walk(visitor);
+        });
+    }
+}, AST_DWLoop);
+
+var AST_While = DEFNODE("While", null, {
+    $documentation: "A `while` statement",
     _walk: function(visitor) {
         return visitor._visit(this, function(){
             this.condition._walk(visitor);
             this.body._walk(visitor);
         });
     }
-}, AST_StatementWithBody);
-
-var AST_Do = DEFNODE("Do", null, {
-    $documentation: "A `do` statement",
-}, AST_DWLoop);
-
-var AST_While = DEFNODE("While", null, {
-    $documentation: "A `while` statement",
 }, AST_DWLoop);
 
 var AST_For = DEFNODE("For", "init condition step", {
@@ -233,7 +273,7 @@ var AST_For = DEFNODE("For", "init condition step", {
             this.body._walk(visitor);
         });
     }
-}, AST_StatementWithBody);
+}, AST_IterationStatement);
 
 var AST_ForIn = DEFNODE("ForIn", "init name object", {
     $documentation: "A `for ... in` statement",
@@ -249,7 +289,11 @@ var AST_ForIn = DEFNODE("ForIn", "init name object", {
             this.body._walk(visitor);
         });
     }
-}, AST_StatementWithBody);
+}, AST_IterationStatement);
+
+var AST_ForOf = DEFNODE("ForOf", null, {
+    $documentation: "A `for ... of` statement",
+}, AST_ForIn);
 
 var AST_With = DEFNODE("With", "expression", {
     $documentation: "A `with` statement",
@@ -278,6 +322,13 @@ var AST_Scope = DEFNODE("Scope", "directives variables functions uses_with uses_
         enclosed: "[SymbolDef*/S] a list of all symbol definitions that are accessed from this scope or any subscopes",
         cname: "[integer/S] current index for mangling variables (used internally by the mangler)",
     },
+    get_defun_scope: function () {
+        var self = this;
+        while (self.is_block_scope() && self.parent_scope) {
+            self = self.parent_scope;
+        }
+        return self;
+    }
 }, AST_Block);
 
 var AST_Toplevel = DEFNODE("Toplevel", "globals", {
@@ -291,10 +342,10 @@ var AST_Toplevel = DEFNODE("Toplevel", "globals", {
         var parameters = [];
 
         arg_parameter_pairs.forEach(function(pair) {
-            var split = pair.split(":");
+            var splitAt = pair.lastIndexOf(":");
 
-            args.push(split[0]);
-            parameters.push(split[1]);
+            args.push(pair.substr(0, splitAt));
+            parameters.push(pair.substr(splitAt + 1));
         });
 
         var wrapped_tl = "(function(" + parameters.join(",") + "){ '$ORIG'; })(" + args.join(",") + ")";
@@ -318,12 +369,11 @@ var AST_Toplevel = DEFNODE("Toplevel", "globals", {
                 }
             }));
         }
-        var wrapped_tl = "(function(exports, global){ global['" + name + "'] = exports; '$ORIG'; '$EXPORTS'; }({}, (function(){return this}())))";
+        var wrapped_tl = "(function(exports, global){ '$ORIG'; '$EXPORTS'; global['" + name + "'] = exports; }({}, (function(){return this}())))";
         wrapped_tl = parse(wrapped_tl);
         wrapped_tl = wrapped_tl.transform(new TreeTransformer(function before(node){
-            if (node instanceof AST_SimpleStatement) {
-                node = node.body;
-                if (node instanceof AST_String) switch (node.getValue()) {
+            if (node instanceof AST_Directive) {
+                switch (node.value) {
                   case "$ORIG":
                     return MAP.splice(self.body);
                   case "$EXPORTS":
@@ -348,36 +398,199 @@ var AST_Toplevel = DEFNODE("Toplevel", "globals", {
     }
 }, AST_Scope);
 
-var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments", {
+var AST_Expansion = DEFNODE("Expansion", "expression", {
+    $documentation: "An expandible argument, such as ...rest, a splat, such as [1,2,...all], or an expansion in a variable declaration, such as var [first, ...rest] = list",
+    $propdoc: {
+        expression: "AST_Symbol the thing to be expanded"
+    },
+    _walk: function(visitor) {
+        var self = this;
+        return visitor._visit(this, function(){
+            self.expression.walk(visitor);
+        });
+    }
+});
+
+var AST_ArrowParametersOrSeq = DEFNODE("ArrowParametersOrSeq", "expressions", {
+    $documentation: "A set of arrow function parameters or a sequence expression. This is used because when the parser sees a \"(\" it could be the start of a seq, or the start of a parameter list of an arrow function.",
+    $propdoc: {
+        expressions: "[AST_Expression|AST_Destructuring|AST_Expansion*] array of expressions or argument names or destructurings."
+    },
+    as_params: function (croak) {
+        // We don't want anything which doesn't belong in a destructuring
+        var root = this;
+        return this.expressions.map(function to_fun_args(ex, _, __, default_seen_above) {
+            var insert_default = function(ex, default_value) {
+                if (default_value) {
+                    return new AST_DefaultAssign({
+                        start: ex.start,
+                        left: ex,
+                        operator: "=",
+                        right: default_value,
+                        end: default_value.end
+                    });
+                }
+                return ex;
+            }
+            if (ex instanceof AST_Object) {
+                return insert_default(new AST_Destructuring({
+                    start: ex.start,
+                    end: ex.end,
+                    is_array: false,
+                    names: ex.properties.map(to_fun_args)
+                }), default_seen_above);
+            } else if (ex instanceof AST_ObjectKeyVal) {
+                if (ex.key instanceof AST_SymbolRef) {
+                    ex.key = to_fun_args(ex.key, 0, [ex.key]);
+                }
+                ex.value = to_fun_args(ex.value, 0, [ex.key]);
+                return insert_default(ex, default_seen_above);
+            } else if (ex instanceof AST_Hole) {
+                return ex;
+            } else if (ex instanceof AST_Destructuring) {
+                if (ex.names.length == 0)
+                    croak("Invalid destructuring function parameter", ex.start.line, ex.start.col);
+                ex.names = ex.names.map(to_fun_args);
+                return insert_default(ex, default_seen_above);
+            } else if (ex instanceof AST_SymbolRef) {
+                return insert_default(new AST_SymbolFunarg({
+                    name: ex.name,
+                    start: ex.start,
+                    end: ex.end
+                }), default_seen_above);
+            } else if (ex instanceof AST_Expansion) {
+                ex.expression = to_fun_args(ex.expression);
+                return insert_default(ex, default_seen_above);
+            } else if (ex instanceof AST_Array) {
+                return insert_default(new AST_Destructuring({
+                    start: ex.start,
+                    end: ex.end,
+                    is_array: true,
+                    names: ex.elements.map(to_fun_args)
+                }), default_seen_above);
+            } else if (ex instanceof AST_Assign) {
+                return insert_default(to_fun_args(ex.left, undefined, undefined, ex.right), default_seen_above);
+            } else {
+                croak("Invalid function parameter", ex.start.line, ex.start.col);
+            }
+        });
+    },
+    as_expr: function (croak) {
+        return AST_Seq.from_array(this.expressions);
+    }
+});
+
+var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments is_generator", {
     $documentation: "Base class for functions",
     $propdoc: {
+        is_generator: "[boolean] is generatorFn or not",
         name: "[AST_SymbolDeclaration?] the name of this function",
-        argnames: "[AST_SymbolFunarg*] array of function arguments",
+        argnames: "[AST_SymbolFunarg|AST_Destructuring|AST_Expansion|AST_DefaultAssign*] array of function arguments, destructurings, or expanding arguments",
         uses_arguments: "[boolean/S] tells whether this function accesses the arguments array"
     },
+    args_as_names: function () {
+        var out = [];
+        for (var i = 0; i < this.argnames.length; i++) {
+            if (this.argnames[i] instanceof AST_Destructuring) {
+                out = out.concat(this.argnames[i].all_symbols());
+            } else {
+                out.push(this.argnames[i]);
+            }
+        }
+        return out;
+    },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
             if (this.name) this.name._walk(visitor);
-            this.argnames.forEach(function(arg){
-                arg._walk(visitor);
-            });
+            var argnames = this.argnames;
+            for (var i = 0, len = argnames.length; i < len; i++) {
+                argnames[i]._walk(visitor);
+            }
             walk_body(this, visitor);
         });
     }
 }, AST_Scope);
 
 var AST_Accessor = DEFNODE("Accessor", null, {
-    $documentation: "A setter/getter function"
+    $documentation: "A setter/getter function.  The `name` property is always null."
 }, AST_Lambda);
 
 var AST_Function = DEFNODE("Function", null, {
     $documentation: "A function expression"
 }, AST_Lambda);
 
+var AST_Arrow = DEFNODE("Arrow", null, {
+    $documentation: "An ES6 Arrow function ((a) => b)"
+}, AST_Lambda);
+
 var AST_Defun = DEFNODE("Defun", null, {
     $documentation: "A function definition"
 }, AST_Lambda);
 
+/* -----[ DESTRUCTURING ]----- */
+var AST_Destructuring = DEFNODE("Destructuring", "names is_array", {
+    $documentation: "A destructuring of several names. Used in destructuring assignment and with destructuring function argument names",
+    $propdoc: {
+        "names": "[AST_Node*] Array of properties or elements",
+        "is_array": "[Boolean] Whether the destructuring represents an object or array"
+    },
+    _walk: function(visitor) {
+        return visitor._visit(this, function(){
+            this.names.forEach(function(name){
+                name._walk(visitor);
+            });
+        });
+    },
+    all_symbols: function() {
+        var out = [];
+        this.walk(new TreeWalker(function (node) {
+            if (node instanceof AST_Symbol) {
+                out.push(node);
+            }
+            if (node instanceof AST_Expansion) {
+                out.push(node.expression);
+            }
+        }));
+        return out;
+    }
+});
+
+var AST_PrefixedTemplateString = DEFNODE("PrefixedTemplateString", "template_string prefix", {
+    $documentation: "A templatestring with a prefix, such as String.raw`foobarbaz`",
+    $propdoc: {
+        template_string: "[AST_TemplateString] The template string",
+        prefix: "[AST_SymbolRef|AST_PropAccess] The prefix, which can be a symbol such as `foo` or a dotted expression such as `String.raw`."
+    },
+    _walk: function(visitor) {
+        this.prefix._walk(visitor);
+        this.template_string._walk(visitor);
+    }
+})
+
+var AST_TemplateString = DEFNODE("TemplateString", "segments", {
+    $documentation: "A template string literal",
+    $propdoc: {
+        segments: "[AST_TemplateSegment|AST_Expression]* One or more segments, starting with AST_TemplateSegment. AST_Expression may follow AST_TemplateSegment, but each AST_Expression must be followed by AST_TemplateSegment."
+    },
+    _walk: function(visitor) {
+        return visitor._visit(this, function(){
+            this.segments.forEach(function(seg, i){
+                if (i % 2 !== 0) {
+                    seg._walk(visitor);
+                }
+            });
+        });
+    }
+});
+
+var AST_TemplateSegment = DEFNODE("TemplateSegment", "value raw", {
+    $documentation: "A segment of a template string literal",
+    $propdoc: {
+        value: "Content of the segment",
+        raw: "Raw content of the segment"
+    }
+});
+
 /* -----[ JUMPS ]----- */
 
 var AST_Jump = DEFNODE("Jump", null, {
@@ -494,16 +707,10 @@ var AST_Try = DEFNODE("Try", "bcatch bfinally", {
     }
 }, AST_Block);
 
-// XXX: this is wrong according to ECMA-262 (12.4).  the catch block
-// should introduce another scope, as the argname should be visible
-// only inside the catch block.  However, doing it this way because of
-// IE which simply introduces the name in the surrounding scope.  If
-// we ever want to fix this then AST_Catch should inherit from
-// AST_Scope.
 var AST_Catch = DEFNODE("Catch", "argname", {
     $documentation: "A `catch` node; only makes sense as part of a `try` statement",
     $propdoc: {
-        argname: "[AST_SymbolCatch] symbol for the exception"
+        argname: "[AST_SymbolCatch|AST_Destructuring|AST_Expansion|AST_DefaultAssign] symbol for the exception"
     },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
@@ -526,9 +733,10 @@ var AST_Definitions = DEFNODE("Definitions", "definitions", {
     },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
-            this.definitions.forEach(function(def){
-                def._walk(visitor);
-            });
+            var definitions = this.definitions;
+            for (var i = 0, len = definitions.length; i < len; i++) {
+                definitions[i]._walk(visitor);
+            }
         });
     }
 }, AST_Statement);
@@ -537,14 +745,73 @@ var AST_Var = DEFNODE("Var", null, {
     $documentation: "A `var` statement"
 }, AST_Definitions);
 
+var AST_Let = DEFNODE("Let", null, {
+    $documentation: "A `let` statement"
+}, AST_Definitions);
+
 var AST_Const = DEFNODE("Const", null, {
     $documentation: "A `const` statement"
 }, AST_Definitions);
 
+var AST_NameImport = DEFNODE("NameImport", "foreign_name name", {
+    $documentation: "The part of the import statement that imports names from a module.",
+    $propdoc: {
+        foreign_name: "[AST_SymbolImportForeign] The name being imported (as specified in the module)",
+        name: "[AST_SymbolImport] The name as it becomes available to this module."
+    },
+    _walk: function (visitor) {
+        return visitor._visit(this, function() {
+            this.foreign_name._walk(visitor);
+            this.name._walk(visitor);
+        });
+    }
+})
+
+var AST_Import = DEFNODE("Import", "imported_name imported_names module_name", {
+    $documentation: "An `import` statement",
+    $propdoc: {
+        imported_name: "[AST_SymbolImport] The name of the variable holding the module's default export.",
+        imported_names: "[AST_NameImport*] The names of non-default imported variables",
+        module_name: "[AST_String] String literal describing where this module came from",
+    },
+    _walk: function(visitor) {
+        return visitor._visit(this, function() {
+            if (this.imported_name) {
+                this.imported_name._walk(visitor);
+            }
+            if (this.imported_names) {
+                this.imported_names.forEach(function (name_import) {
+                    name_import._walk(visitor);
+                });
+            }
+            this.module_name._walk(visitor);
+        });
+    }
+});
+
+var AST_Export = DEFNODE("Export", "exported_definition exported_value is_default", {
+    $documentation: "An `export` statement",
+    $propdoc: {
+        exported_definition: "[AST_Defun|AST_Definitions|AST_DefClass?] An exported definition",
+        exported_value: "[AST_Node?] An exported value",
+        is_default: "[Boolean] Whether this is the default exported value of this module"
+    },
+    _walk: function (visitor) {
+        visitor._visit(this, function () {
+            if (this.exported_definition) {
+                this.exported_definition._walk(visitor);
+            }
+            if (this.exported_value) {
+                this.exported_value._walk(visitor);
+            }
+        });
+    }
+}, AST_Statement);
+
 var AST_VarDef = DEFNODE("VarDef", "name value", {
     $documentation: "A variable declaration; only appears in a AST_Definitions node",
     $propdoc: {
-        name: "[AST_SymbolVar|AST_SymbolConst] name of the variable",
+        name: "[AST_SymbolVar|AST_SymbolConst|AST_Destructuring] name of the variable",
         value: "[AST_Node?] initializer, or null of there's no initializer"
     },
     _walk: function(visitor) {
@@ -566,9 +833,10 @@ var AST_Call = DEFNODE("Call", "expression args", {
     _walk: function(visitor) {
         return visitor._visit(this, function(){
             this.expression._walk(visitor);
-            this.args.forEach(function(arg){
-                arg._walk(visitor);
-            });
+            var args = this.args;
+            for (var i = 0, len = args.length; i < len; i++) {
+                args[i]._walk(visitor);
+            }
         });
     }
 });
@@ -628,6 +896,13 @@ var AST_Seq = DEFNODE("Seq", "car cdr", {
             p = p.cdr;
         }
     },
+    len: function() {
+        if (this.cdr instanceof AST_Seq) {
+            return this.cdr.len() + 1;
+        } else {
+            return 2;
+        }
+    },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
             this.car._walk(visitor);
@@ -719,6 +994,10 @@ var AST_Assign = DEFNODE("Assign", null, {
     $documentation: "An assignment expression — `a = b + 5`",
 }, AST_Binary);
 
+var AST_DefaultAssign = DEFNODE("DefaultAssign", null, {
+    $documentation: "A default assignment expression like in `(a = 3) => a`"
+}, AST_Binary);
+
 /* -----[ LITERALS ]----- */
 
 var AST_Array = DEFNODE("Array", "elements", {
@@ -728,9 +1007,10 @@ var AST_Array = DEFNODE("Array", "elements", {
     },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
-            this.elements.forEach(function(el){
-                el._walk(visitor);
-            });
+            var elements = this.elements;
+            for (var i = 0, len = elements.length; i < len; i++) {
+                elements[i]._walk(visitor);
+            }
         });
     }
 });
@@ -742,9 +1022,10 @@ var AST_Object = DEFNODE("Object", "properties", {
     },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
-            this.properties.forEach(function(prop){
-                prop._walk(visitor);
-            });
+            var properties = this.properties;
+            for (var i = 0, len = properties.length; i < len; i++) {
+                properties[i]._walk(visitor);
+            }
         });
     }
 });
@@ -752,35 +1033,91 @@ var AST_Object = DEFNODE("Object", "properties", {
 var AST_ObjectProperty = DEFNODE("ObjectProperty", "key value", {
     $documentation: "Base class for literal object properties",
     $propdoc: {
-        key: "[string] the property name; it's always a plain string in our AST, no matter if it was a string, number or identifier in original code",
-        value: "[AST_Node] property value.  For setters and getters this is an AST_Function."
+        key: "[string|AST_Node] the property name converted to a string for ObjectKeyVal. For setters, getters and computed property this is an arbitrary AST_Node",
+        value: "[AST_Node] property value. For setters and getters this is an AST_Function."
     },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
+            if (this.key instanceof AST_Node)
+                this.key._walk(visitor);
             this.value._walk(visitor);
         });
     }
 });
 
-var AST_ObjectKeyVal = DEFNODE("ObjectKeyVal", null, {
+var AST_ObjectKeyVal = DEFNODE("ObjectKeyVal", "quote", {
     $documentation: "A key: value object property",
+    $propdoc: {
+        quote: "[string] the original quote character"
+    }
 }, AST_ObjectProperty);
 
-var AST_ObjectSetter = DEFNODE("ObjectSetter", null, {
+var AST_ObjectSetter = DEFNODE("ObjectSetter", "quote static", {
+    $propdoc: {
+        quote: "[string|undefined] the original quote character, if any",
+        static: "[boolean] whether this is a static setter (classes only)"
+    },
     $documentation: "An object setter property",
 }, AST_ObjectProperty);
 
-var AST_ObjectGetter = DEFNODE("ObjectGetter", null, {
+var AST_ObjectGetter = DEFNODE("ObjectGetter", "quote static", {
+    $propdoc: {
+        quote: "[string|undefined] the original quote character, if any",
+        static: "[boolean] whether this is a static getter (classes only)"
+    },
     $documentation: "An object getter property",
 }, AST_ObjectProperty);
 
+var AST_ConciseMethod = DEFNODE("ConciseMethod", "quote static is_generator", {
+    $propdoc: {
+        quote: "[string|undefined] the original quote character, if any",
+        static: "[boolean] whether this method is static (classes only)",
+        is_generator: "[boolean] is generatorFn or not",
+    },
+    $documentation: "An ES6 concise method inside an object or class"
+}, AST_ObjectProperty);
+
+var AST_Class = DEFNODE("Class", "name extends properties", {
+    $propdoc: {
+        name: "[AST_SymbolClass|AST_SymbolDefClass?] optional class name.",
+        extends: "[AST_Node]? optional parent class",
+        properties: "[AST_ObjectProperty*] array of properties"
+    },
+    $documentation: "An ES6 class",
+    _walk: function(visitor) {
+        return visitor._visit(this, function(){
+            if (this.name) {
+                this.name._walk(visitor);
+            }
+            if (this.extends) {
+                this.extends._walk(visitor);
+            }
+            this.properties.forEach(function(prop){
+                prop._walk(visitor);
+            });
+        });
+    },
+}, AST_Scope);
+
+var AST_DefClass = DEFNODE("DefClass", null, {
+    $documentation: "A class definition",
+}, AST_Class);
+
+var AST_ClassExpression = DEFNODE("ClassExpression", null, {
+    $documentation: "A class expression."
+}, AST_Class);
+
 var AST_Symbol = DEFNODE("Symbol", "scope name thedef", {
     $propdoc: {
         name: "[string] name of this symbol",
         scope: "[AST_Scope/S] the current scope (not necessarily the definition scope)",
         thedef: "[SymbolDef/S] the definition of this symbol"
     },
-    $documentation: "Base class for all symbols",
+    $documentation: "Base class for all symbols"
+});
+
+var AST_NewTarget = DEFNODE("NewTarget", null, {
+    $documentation: "A reference to new.target"
 });
 
 var AST_SymbolAccessor = DEFNODE("SymbolAccessor", null, {
@@ -789,18 +1126,23 @@ var AST_SymbolAccessor = DEFNODE("SymbolAccessor", null, {
 
 var AST_SymbolDeclaration = DEFNODE("SymbolDeclaration", "init", {
     $documentation: "A declaration symbol (symbol in var/const, function name or argument, symbol in catch)",
-    $propdoc: {
-        init: "[AST_Node*/S] array of initializers for this declaration."
-    }
 }, AST_Symbol);
 
 var AST_SymbolVar = DEFNODE("SymbolVar", null, {
     $documentation: "Symbol defining a variable",
 }, AST_SymbolDeclaration);
 
+var AST_SymbolBlockDeclaration = DEFNODE("SymbolBlockDeclaration", null, {
+    $documentation: "Base class for block-scoped declaration symbols"
+}, AST_SymbolDeclaration);
+
 var AST_SymbolConst = DEFNODE("SymbolConst", null, {
     $documentation: "A constant declaration"
-}, AST_SymbolDeclaration);
+}, AST_SymbolBlockDeclaration);
+
+var AST_SymbolLet = DEFNODE("SymbolLet", null, {
+    $documentation: "A block-scoped `let` declaration"
+}, AST_SymbolBlockDeclaration);
 
 var AST_SymbolFunarg = DEFNODE("SymbolFunarg", null, {
     $documentation: "Symbol naming a function argument",
@@ -810,18 +1152,42 @@ var AST_SymbolDefun = DEFNODE("SymbolDefun", null, {
     $documentation: "Symbol defining a function",
 }, AST_SymbolDeclaration);
 
+var AST_SymbolMethod = DEFNODE("SymbolMethod", null, {
+    $documentation: "Symbol in an object defining a method",
+}, AST_Symbol);
+
 var AST_SymbolLambda = DEFNODE("SymbolLambda", null, {
     $documentation: "Symbol naming a function expression",
 }, AST_SymbolDeclaration);
 
+var AST_SymbolDefClass = DEFNODE("SymbolDefClass", null, {
+    $documentation: "Symbol naming a class's name in a class declaration. Lexically scoped to its containing scope, and accessible within the class."
+}, AST_SymbolBlockDeclaration);
+
+var AST_SymbolClass = DEFNODE("SymbolClass", null, {
+    $documentation: "Symbol naming a class's name. Lexically scoped to the class."
+}, AST_SymbolDeclaration);
+
 var AST_SymbolCatch = DEFNODE("SymbolCatch", null, {
     $documentation: "Symbol naming the exception in catch",
-}, AST_SymbolDeclaration);
+}, AST_SymbolBlockDeclaration);
+
+var AST_SymbolImport = DEFNODE("SymbolImport", null, {
+    $documentation: "Symbol refering to an imported name",
+}, AST_SymbolBlockDeclaration);
+
+var AST_SymbolImportForeign = DEFNODE("SymbolImportForeign", null, {
+    $documentation: "A symbol imported from a module, but it is defined in the other module, and its real name is irrelevant for this module's purposes",
+}, AST_Symbol);
 
 var AST_Label = DEFNODE("Label", "references", {
     $documentation: "Symbol naming a label (declaration)",
     $propdoc: {
-        references: "[AST_LabelRef*] a list of nodes referring to this label"
+        references: "[AST_LoopControl*] a list of nodes referring to this label"
+    },
+    initialize: function() {
+        this.references = [];
+        this.thedef = this;
     }
 }, AST_Symbol);
 
@@ -837,6 +1203,10 @@ var AST_This = DEFNODE("This", null, {
     $documentation: "The `this` symbol",
 }, AST_Symbol);
 
+var AST_Super = DEFNODE("Super", null, {
+    $documentation: "The `super` symbol",
+}, AST_Symbol);
+
 var AST_Constant = DEFNODE("Constant", null, {
     $documentation: "Base class for all constants",
     getValue: function() {
@@ -844,17 +1214,19 @@ var AST_Constant = DEFNODE("Constant", null, {
     }
 });
 
-var AST_String = DEFNODE("String", "value", {
+var AST_String = DEFNODE("String", "value quote", {
     $documentation: "A string literal",
     $propdoc: {
-        value: "[string] the contents of this string"
+        value: "[string] the contents of this string",
+        quote: "[string] the original quote character"
     }
 }, AST_Constant);
 
-var AST_Number = DEFNODE("Number", "value", {
+var AST_Number = DEFNODE("Number", "value literal", {
     $documentation: "A number literal",
     $propdoc: {
-        value: "[number] the numeric value"
+        value: "[number] the numeric value",
+        literal: "[string] numeric value as string (optional)"
     }
 }, AST_Constant);
 
@@ -908,32 +1280,61 @@ var AST_True = DEFNODE("True", null, {
     value: true
 }, AST_Boolean);
 
+/* -----[ Yield ]----- */
+
+var AST_Yield = DEFNODE("Yield", "expression is_star", {
+    $documentation: "A `yield` statement",
+    $propdoc: {
+        expression: "[AST_Node?] the value returned or thrown by this statement; could be null (representing undefined) but only when is_star is set to false",
+        is_star: "[Boolean] Whether this is a yield or yield* statement"
+    },
+    _walk: function(visitor) {
+        return visitor._visit(this, this.expression && function(){
+            this.expression._walk(visitor);
+        });
+    }
+});
+
 /* -----[ TreeWalker ]----- */
 
 function TreeWalker(callback) {
     this.visit = callback;
     this.stack = [];
+    this.directives = Object.create(null);
 };
 TreeWalker.prototype = {
     _visit: function(node, descend) {
-        this.stack.push(node);
+        this.push(node);
         var ret = this.visit(node, descend ? function(){
             descend.call(node);
         } : noop);
         if (!ret && descend) {
             descend.call(node);
         }
-        this.stack.pop();
+        this.pop(node);
         return ret;
     },
     parent: function(n) {
         return this.stack[this.stack.length - 2 - (n || 0)];
     },
     push: function (node) {
+        if (node instanceof AST_Lambda) {
+            this.directives = Object.create(this.directives);
+        } else if (node instanceof AST_Directive && !this.directives[node.value]) {
+            this.directives[node.value] = node;
+        } else if (node instanceof AST_Class) {
+            this.directives = Object.create(this.directives);
+            if (!this.directives["use strict"]) {
+                this.directives["use strict"] = node;
+            }
+        }
         this.stack.push(node);
     },
-    pop: function() {
-        return this.stack.pop();
+    pop: function(node) {
+        this.stack.pop();
+        if (node instanceof AST_Lambda || node instanceof AST_Class) {
+            this.directives = Object.getPrototypeOf(this.directives);
+        }
     },
     self: function() {
         return this.stack[this.stack.length - 1];
@@ -945,6 +1346,18 @@ TreeWalker.prototype = {
             if (x instanceof type) return x;
         }
     },
+    has_directive: function(type) {
+        var dir = this.directives[type];
+        if (dir) return dir;
+        var node = this.stack[this.stack.length - 1];
+        if (node instanceof AST_Scope && node.body) {
+            for (var i = 0; i < node.body.length; ++i) {
+                var st = node.body[i];
+                if (!(st instanceof AST_Directive)) break;
+                if (st.value == type) return st;
+            }
+        }
+    },
     in_boolean_context: function() {
         var stack = this.stack;
         var i = stack.length, self = stack[--i];
@@ -965,21 +1378,15 @@ TreeWalker.prototype = {
     },
     loopcontrol_target: function(label) {
         var stack = this.stack;
-        if (label) {
-            for (var i = stack.length; --i >= 0;) {
-                var x = stack[i];
-                if (x instanceof AST_LabeledStatement && x.label.name == label.name) {
-                    return x.body;
-                }
-            }
-        } else {
-            for (var i = stack.length; --i >= 0;) {
-                var x = stack[i];
-                if (x instanceof AST_Switch
-                    || x instanceof AST_For
-                    || x instanceof AST_ForIn
-                    || x instanceof AST_DWLoop) return x;
+        if (label) for (var i = stack.length; --i >= 0;) {
+            var x = stack[i];
+            if (x instanceof AST_LabeledStatement && x.label.name == label.name) {
+                return x.body;
             }
+        } else for (var i = stack.length; --i >= 0;) {
+            var x = stack[i];
+            if (x instanceof AST_Switch || x instanceof AST_IterationStatement)
+                return x;
         }
     }
 };

lib/mozilla-ast.js

@@ -45,54 +45,113 @@
 
 (function(){
 
+    var normalize_directives = function(body) {
+        var in_directive = true;
+
+        for (var i = 0; i < body.length; i++) {
+            if (in_directive && body[i] instanceof AST_Statement && body[i].body instanceof AST_String) {
+                body[i] = new AST_Directive({
+                    start: body[i].start,
+                    end: body[i].end,
+                    value: body[i].body.value
+                });
+            } else if (in_directive && !(body[i] instanceof AST_Statement && body[i].body instanceof AST_String)) {
+                in_directive = false;
+            }
+        }
+
+        return body;
+    };
+
     var MOZ_TO_ME = {
-        TryStatement : function(M) {
+        Program: function(M) {
+            return new AST_Toplevel({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                body: normalize_directives(M.body.map(from_moz))
+            });
+        },
+        FunctionDeclaration: function(M) {
+            return new AST_Defun({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                name: from_moz(M.id),
+                argnames: M.params.map(from_moz),
+                body: normalize_directives(from_moz(M.body).body)
+            });
+        },
+        FunctionExpression: function(M) {
+            return new AST_Function({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                name: from_moz(M.id),
+                argnames: M.params.map(from_moz),
+                body: normalize_directives(from_moz(M.body).body)
+            });
+        },
+        ExpressionStatement: function(M) {
+            return new AST_SimpleStatement({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                body: from_moz(M.expression)
+            });
+        },
+        TryStatement: function(M) {
+            var handlers = M.handlers || [M.handler];
+            if (handlers.length > 1 || M.guardedHandlers && M.guardedHandlers.length) {
+                throw new Error("Multiple catch clauses are not supported.");
+            }
             return new AST_Try({
                 start    : my_start_token(M),
                 end      : my_end_token(M),
                 body     : from_moz(M.block).body,
-                bcatch   : from_moz(M.handlers[0]),
+                bcatch   : from_moz(handlers[0]),
                 bfinally : M.finalizer ? new AST_Finally(from_moz(M.finalizer)) : null
             });
         },
-        CatchClause : function(M) {
-            return new AST_Catch({
-                start   : my_start_token(M),
-                end     : my_end_token(M),
-                argname : from_moz(M.param),
-                body    : from_moz(M.body).body
+        Property: function(M) {
+            var key = M.key;
+            var name = key.type == "Identifier" ? key.name : key.value;
+            var args = {
+                start    : my_start_token(key),
+                end      : my_end_token(M.value),
+                key      : name,
+                value    : from_moz(M.value)
+            };
+            switch (M.kind) {
+              case "init":
+                return new AST_ObjectKeyVal(args);
+              case "set":
+                args.value.name = from_moz(key);
+                return new AST_ObjectSetter(args);
+              case "get":
+                args.value.name = from_moz(key);
+                return new AST_ObjectGetter(args);
+            }
+        },
+        ArrayExpression: function(M) {
+            return new AST_Array({
+                start    : my_start_token(M),
+                end      : my_end_token(M),
+                elements : M.elements.map(function(elem){
+                    return elem === null ? new AST_Hole() : from_moz(elem);
+                })
             });
         },
-        ObjectExpression : function(M) {
+        ObjectExpression: function(M) {
             return new AST_Object({
                 start      : my_start_token(M),
                 end        : my_end_token(M),
                 properties : M.properties.map(function(prop){
-                    var key = prop.key;
-                    var name = key.type == "Identifier" ? key.name : key.value;
-                    var args = {
-                        start    : my_start_token(key),
-                        end      : my_end_token(prop.value),
-                        key      : name,
-                        value    : from_moz(prop.value)
-                    };
-                    switch (prop.kind) {
-                      case "init":
-                        return new AST_ObjectKeyVal(args);
-                      case "set":
-                        args.value.name = from_moz(key);
-                        return new AST_ObjectSetter(args);
-                      case "get":
-                        args.value.name = from_moz(key);
-                        return new AST_ObjectGetter(args);
-                    }
+                    prop.type = "Property";
+                    return from_moz(prop)
                 })
             });
         },
-        SequenceExpression : function(M) {
+        SequenceExpression: function(M) {
             return AST_Seq.from_array(M.expressions.map(from_moz));
         },
-        MemberExpression : function(M) {
+        MemberExpression: function(M) {
             return new (M.computed ? AST_Sub : AST_Dot)({
                 start      : my_start_token(M),
                 end        : my_end_token(M),
@@ -100,7 +159,7 @@
                 expression : from_moz(M.object)
             });
         },
-        SwitchCase : function(M) {
+        SwitchCase: function(M) {
             return new (M.test ? AST_Case : AST_Default)({
                 start      : my_start_token(M),
                 end        : my_end_token(M),
@@ -108,7 +167,14 @@
                 body       : M.consequent.map(from_moz)
             });
         },
-        Literal : function(M) {
+        VariableDeclaration: function(M) {
+            return new (M.kind === "const" ? AST_Const : AST_Var)({
+                start       : my_start_token(M),
+                end         : my_end_token(M),
+                definitions : M.declarations.map(from_moz)
+            });
+        },
+        Literal: function(M) {
             var val = M.value, args = {
                 start  : my_start_token(M),
                 end    : my_end_token(M)
@@ -124,16 +190,20 @@
               case "boolean":
                 return new (val ? AST_True : AST_False)(args);
               default:
-                args.value = val;
+                var rx = M.regex;
+                if (rx && rx.pattern) {
+                    // RegExpLiteral as per ESTree AST spec
+                    args.value = new RegExp(rx.pattern, rx.flags).toString();
+                } else {
+                    // support legacy RegExp
+                    args.value = M.regex && M.raw ? M.raw : val;
+                }
                 return new AST_RegExp(args);
             }
         },
-        UnaryExpression: From_Moz_Unary,
-        UpdateExpression: From_Moz_Unary,
         Identifier: function(M) {
             var p = FROM_MOZ_STACK[FROM_MOZ_STACK.length - 2];
-            return new (M.name == "this" ? AST_This
-                        : p.type == "LabeledStatement" ? AST_Label
+            return new (  p.type == "LabeledStatement" ? AST_Label
                         : p.type == "VariableDeclarator" && p.id === M ? (p.kind == "const" ? AST_SymbolConst : AST_SymbolVar)
                         : p.type == "FunctionExpression" ? (p.id === M ? AST_SymbolLambda : AST_SymbolFunarg)
                         : p.type == "FunctionDeclaration" ? (p.id === M ? AST_SymbolDefun : AST_SymbolFunarg)
@@ -147,7 +217,8 @@
         }
     };
 
-    function From_Moz_Unary(M) {
+    MOZ_TO_ME.UpdateExpression =
+    MOZ_TO_ME.UnaryExpression = function To_Moz_Unary(M) {
         var prefix = "prefix" in M ? M.prefix
             : M.type == "UnaryExpression" ? true : false;
         return new (prefix ? AST_UnaryPrefix : AST_UnaryPostfix)({
@@ -158,14 +229,8 @@
         });
     };
 
-    var ME_TO_MOZ = {};
-
-    map("Node", AST_Node);
-    map("Program", AST_Toplevel, "body@body");
-    map("Function", AST_Function, "id>name, params@argnames, body%body");
     map("EmptyStatement", AST_EmptyStatement);
     map("BlockStatement", AST_BlockStatement, "body@body");
-    map("ExpressionStatement", AST_SimpleStatement, "expression>body");
     map("IfStatement", AST_If, "test>condition, consequent>body, alternate>alternative");
     map("LabeledStatement", AST_LabeledStatement, "label>label, body>body");
     map("BreakStatement", AST_Break, "label>label");
@@ -179,72 +244,314 @@
     map("ForStatement", AST_For, "init>init, test>condition, update>step, body>body");
     map("ForInStatement", AST_ForIn, "left>init, right>object, body>body");
     map("DebuggerStatement", AST_Debugger);
-    map("FunctionDeclaration", AST_Defun, "id>name, params@argnames, body%body");
-    map("VariableDeclaration", AST_Var, "declarations@definitions");
     map("VariableDeclarator", AST_VarDef, "id>name, init>value");
+    map("CatchClause", AST_Catch, "param>argname, body%body");
 
     map("ThisExpression", AST_This);
-    map("ArrayExpression", AST_Array, "elements@elements");
-    map("FunctionExpression", AST_Function, "id>name, params@argnames, body%body");
     map("BinaryExpression", AST_Binary, "operator=operator, left>left, right>right");
-    map("AssignmentExpression", AST_Assign, "operator=operator, left>left, right>right");
     map("LogicalExpression", AST_Binary, "operator=operator, left>left, right>right");
+    map("AssignmentExpression", AST_Assign, "operator=operator, left>left, right>right");
     map("ConditionalExpression", AST_Conditional, "test>condition, consequent>consequent, alternate>alternative");
     map("NewExpression", AST_New, "callee>expression, arguments@args");
     map("CallExpression", AST_Call, "callee>expression, arguments@args");
 
+    def_to_moz(AST_Toplevel, function To_Moz_Program(M) {
+        return {
+            type: "Program",
+            body: M.body.map(to_moz)
+        };
+    });
+
+    def_to_moz(AST_Defun, function To_Moz_FunctionDeclaration(M) {
+        return {
+            type: "FunctionDeclaration",
+            id: to_moz(M.name),
+            params: M.argnames.map(to_moz),
+            body: to_moz_block(M)
+        }
+    });
+
+    def_to_moz(AST_Function, function To_Moz_FunctionExpression(M) {
+        return {
+            type: "FunctionExpression",
+            id: to_moz(M.name),
+            params: M.argnames.map(to_moz),
+            body: to_moz_block(M)
+        }
+    });
+
+    def_to_moz(AST_Directive, function To_Moz_Directive(M) {
+        return {
+            type: "ExpressionStatement",
+            expression: {
+                type: "Literal",
+                value: M.value
+            }
+        };
+    });
+
+    def_to_moz(AST_SimpleStatement, function To_Moz_ExpressionStatement(M) {
+        return {
+            type: "ExpressionStatement",
+            expression: to_moz(M.body)
+        };
+    });
+
+    def_to_moz(AST_SwitchBranch, function To_Moz_SwitchCase(M) {
+        return {
+            type: "SwitchCase",
+            test: to_moz(M.expression),
+            consequent: M.body.map(to_moz)
+        };
+    });
+
+    def_to_moz(AST_Try, function To_Moz_TryStatement(M) {
+        return {
+            type: "TryStatement",
+            block: to_moz_block(M),
+            handler: to_moz(M.bcatch),
+            guardedHandlers: [],
+            finalizer: to_moz(M.bfinally)
+        };
+    });
+
+    def_to_moz(AST_Catch, function To_Moz_CatchClause(M) {
+        return {
+            type: "CatchClause",
+            param: to_moz(M.argname),
+            guard: null,
+            body: to_moz_block(M)
+        };
+    });
+
+    def_to_moz(AST_Definitions, function To_Moz_VariableDeclaration(M) {
+        return {
+            type: "VariableDeclaration",
+            kind: M instanceof AST_Const ? "const" : "var",
+            declarations: M.definitions.map(to_moz)
+        };
+    });
+
+    def_to_moz(AST_Seq, function To_Moz_SequenceExpression(M) {
+        return {
+            type: "SequenceExpression",
+            expressions: M.to_array().map(to_moz)
+        };
+    });
+
+    def_to_moz(AST_PropAccess, function To_Moz_MemberExpression(M) {
+        var isComputed = M instanceof AST_Sub;
+        return {
+            type: "MemberExpression",
+            object: to_moz(M.expression),
+            computed: isComputed,
+            property: isComputed ? to_moz(M.property) : {type: "Identifier", name: M.property}
+        };
+    });
+
+    def_to_moz(AST_Unary, function To_Moz_Unary(M) {
+        return {
+            type: M.operator == "++" || M.operator == "--" ? "UpdateExpression" : "UnaryExpression",
+            operator: M.operator,
+            prefix: M instanceof AST_UnaryPrefix,
+            argument: to_moz(M.expression)
+        };
+    });
+
+    def_to_moz(AST_Binary, function To_Moz_BinaryExpression(M) {
+        return {
+            type: M.operator == "&&" || M.operator == "||" ? "LogicalExpression" : "BinaryExpression",
+            left: to_moz(M.left),
+            operator: M.operator,
+            right: to_moz(M.right)
+        };
+    });
+
+    def_to_moz(AST_Array, function To_Moz_ArrayExpression(M) {
+        return {
+            type: "ArrayExpression",
+            elements: M.elements.map(to_moz)
+        };
+    });
+
+    def_to_moz(AST_Object, function To_Moz_ObjectExpression(M) {
+        return {
+            type: "ObjectExpression",
+            properties: M.properties.map(to_moz)
+        };
+    });
+
+    def_to_moz(AST_ObjectProperty, function To_Moz_Property(M) {
+        var key = (
+            is_identifier(M.key)
+            ? {type: "Identifier", name: M.key}
+            : {type: "Literal", value: M.key}
+        );
+        var kind;
+        if (M instanceof AST_ObjectKeyVal) {
+            kind = "init";
+        } else
+        if (M instanceof AST_ObjectGetter) {
+            kind = "get";
+        } else
+        if (M instanceof AST_ObjectSetter) {
+            kind = "set";
+        }
+        return {
+            type: "Property",
+            kind: kind,
+            key: key,
+            value: to_moz(M.value)
+        };
+    });
+
+    def_to_moz(AST_Symbol, function To_Moz_Identifier(M) {
+        var def = M.definition();
+        return {
+            type: "Identifier",
+            name: def ? def.mangled_name || def.name : M.name
+        };
+    });
+
+    def_to_moz(AST_RegExp, function To_Moz_RegExpLiteral(M) {
+        var value = M.value;
+        return {
+            type: "Literal",
+            value: value,
+            raw: value.toString(),
+            regex: {
+                pattern: value.source,
+                flags: value.toString().match(/[gimuy]*$/)[0]
+            }
+        };
+    });
+
+    def_to_moz(AST_Constant, function To_Moz_Literal(M) {
+        var value = M.value;
+        if (typeof value === 'number' && (value < 0 || (value === 0 && 1 / value < 0))) {
+            return {
+                type: "UnaryExpression",
+                operator: "-",
+                prefix: true,
+                argument: {
+                    type: "Literal",
+                    value: -value,
+                    raw: M.start.raw
+                }
+            };
+        }
+        return {
+            type: "Literal",
+            value: value,
+            raw: M.start.raw
+        };
+    });
+
+    def_to_moz(AST_Atom, function To_Moz_Atom(M) {
+        return {
+            type: "Identifier",
+            name: String(M.value)
+        };
+    });
+
+    AST_Boolean.DEFMETHOD("to_mozilla_ast", AST_Constant.prototype.to_mozilla_ast);
+    AST_Null.DEFMETHOD("to_mozilla_ast", AST_Constant.prototype.to_mozilla_ast);
+    AST_Hole.DEFMETHOD("to_mozilla_ast", function To_Moz_ArrayHole() { return null });
+
+    AST_Block.DEFMETHOD("to_mozilla_ast", AST_BlockStatement.prototype.to_mozilla_ast);
+    AST_Lambda.DEFMETHOD("to_mozilla_ast", AST_Function.prototype.to_mozilla_ast);
+
     /* -----[ tools ]----- */
 
+    function raw_token(moznode) {
+        if (moznode.type == "Literal") {
+            return moznode.raw != null ? moznode.raw : moznode.value + "";
+        }
+    }
+
     function my_start_token(moznode) {
+        var loc = moznode.loc, start = loc && loc.start;
+        var range = moznode.range;
         return new AST_Token({
-            file   : moznode.loc && moznode.loc.source,
-            line   : moznode.loc && moznode.loc.start.line,
-            col    : moznode.loc && moznode.loc.start.column,
-            pos    : moznode.start,
-            endpos : moznode.start
+            file    : loc && loc.source,
+            line    : start && start.line,
+            col     : start && start.column,
+            pos     : range ? range[0] : moznode.start,
+            endline : start && start.line,
+            endcol  : start && start.column,
+            endpos  : range ? range[0] : moznode.start,
+            raw     : raw_token(moznode),
         });
     };
 
     function my_end_token(moznode) {
+        var loc = moznode.loc, end = loc && loc.end;
+        var range = moznode.range;
         return new AST_Token({
-            file   : moznode.loc && moznode.loc.source,
-            line   : moznode.loc && moznode.loc.end.line,
-            col    : moznode.loc && moznode.loc.end.column,
-            pos    : moznode.end,
-            endpos : moznode.end
+            file    : loc && loc.source,
+            line    : end && end.line,
+            col     : end && end.column,
+            pos     : range ? range[1] : moznode.end,
+            endline : end && end.line,
+            endcol  : end && end.column,
+            endpos  : range ? range[1] : moznode.end,
+            raw     : raw_token(moznode),
         });
     };
 
     function map(moztype, mytype, propmap) {
         var moz_to_me = "function From_Moz_" + moztype + "(M){\n";
-        moz_to_me += "return new mytype({\n" +
+        moz_to_me += "return new U2." + mytype.name + "({\n" +
             "start: my_start_token(M),\n" +
             "end: my_end_token(M)";
 
+        var me_to_moz = "function To_Moz_" + moztype + "(M){\n";
+        me_to_moz += "return {\n" +
+            "type: " + JSON.stringify(moztype);
+
         if (propmap) propmap.split(/\s*,\s*/).forEach(function(prop){
             var m = /([a-z0-9$_]+)(=|@|>|%)([a-z0-9$_]+)/i.exec(prop);
             if (!m) throw new Error("Can't understand property map: " + prop);
-            var moz = "M." + m[1], how = m[2], my = m[3];
+            var moz = m[1], how = m[2], my = m[3];
             moz_to_me += ",\n" + my + ": ";
-            if (how == "@") {
-                moz_to_me += moz + ".map(from_moz)";
-            } else if (how == ">") {
-                moz_to_me += "from_moz(" + moz + ")";
-            } else if (how == "=") {
-                moz_to_me += moz;
-            } else if (how == "%") {
-                moz_to_me += "from_moz(" + moz + ").body";
-            } else throw new Error("Can't understand operator in propmap: " + prop);
+            me_to_moz += ",\n" + moz + ": ";
+            switch (how) {
+                case "@":
+                    moz_to_me += "M." + moz + ".map(from_moz)";
+                    me_to_moz += "M." +  my + ".map(to_moz)";
+                    break;
+                case ">":
+                    moz_to_me += "from_moz(M." + moz + ")";
+                    me_to_moz += "to_moz(M." + my + ")";
+                    break;
+                case "=":
+                    moz_to_me += "M." + moz;
+                    me_to_moz += "M." + my;
+                    break;
+                case "%":
+                    moz_to_me += "from_moz(M." + moz + ").body";
+                    me_to_moz += "to_moz_block(M)";
+                    break;
+                default:
+                    throw new Error("Can't understand operator in propmap: " + prop);
+            }
         });
-        moz_to_me += "\n})}";
 
-        // moz_to_me = parse(moz_to_me).print_to_string({ beautify: true });
-        // console.log(moz_to_me);
+        moz_to_me += "\n})\n}";
+        me_to_moz += "\n}\n}";
 
-        moz_to_me = new Function("mytype", "my_start_token", "my_end_token", "from_moz", "return(" + moz_to_me + ")")(
-            mytype, my_start_token, my_end_token, from_moz
+        //moz_to_me = parse(moz_to_me).print_to_string({ beautify: true });
+        //me_to_moz = parse(me_to_moz).print_to_string({ beautify: true });
+        //console.log(moz_to_me);
+
+        moz_to_me = new Function("U2", "my_start_token", "my_end_token", "from_moz", "return(" + moz_to_me + ")")(
+            exports, my_start_token, my_end_token, from_moz
         );
-        return MOZ_TO_ME[moztype] = moz_to_me;
+        me_to_moz = new Function("to_moz", "to_moz_block", "return(" + me_to_moz + ")")(
+            to_moz, to_moz_block
+        );
+        MOZ_TO_ME[moztype] = moz_to_me;
+        def_to_moz(mytype, me_to_moz);
     };
 
     var FROM_MOZ_STACK = null;
@@ -264,4 +571,39 @@
         return ast;
     };
 
+    function set_moz_loc(mynode, moznode, myparent) {
+        var start = mynode.start;
+        var end = mynode.end;
+        if (start.pos != null && end.endpos != null) {
+            moznode.range = [start.pos, end.endpos];
+        }
+        if (start.line) {
+            moznode.loc = {
+                start: {line: start.line, column: start.col},
+                end: end.endline ? {line: end.endline, column: end.endcol} : null
+            };
+            if (start.file) {
+                moznode.loc.source = start.file;
+            }
+        }
+        return moznode;
+    };
+
+    function def_to_moz(mytype, handler) {
+        mytype.DEFMETHOD("to_mozilla_ast", function() {
+            return set_moz_loc(this, handler(this));
+        });
+    };
+
+    function to_moz(node) {
+        return node != null ? node.to_mozilla_ast() : null;
+    };
+
+    function to_moz_block(node) {
+        return {
+            type: "BlockStatement",
+            body: node.body.map(to_moz)
+        };
+    };
+
 })();

lib/propmangle.js

@@ -0,0 +1,282 @@
+/***********************************************************************
+
+  A JavaScript tokenizer / parser / beautifier / compressor.
+  https://github.com/mishoo/UglifyJS2
+
+  -------------------------------- (C) ---------------------------------
+
+                           Author: Mihai Bazon
+                         <mihai.bazon@gmail.com>
+                       http://mihai.bazon.net/blog
+
+  Distributed under the BSD license:
+
+    Copyright 2012 (c) Mihai Bazon <mihai.bazon@gmail.com>
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+
+        * Redistributions of source code must retain the above
+          copyright notice, this list of conditions and the following
+          disclaimer.
+
+        * Redistributions in binary form must reproduce the above
+          copyright notice, this list of conditions and the following
+          disclaimer in the documentation and/or other materials
+          provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER “AS IS” AND ANY
+    EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+    PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE
+    LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+    OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+    TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+    THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+    SUCH DAMAGE.
+
+ ***********************************************************************/
+
+"use strict";
+
+function find_builtins() {
+
+    // Compatibility fix for some standard defined globals not defined on every js environment
+    var new_globals = ["Symbol", "Map", "Promise", "Proxy", "Reflect", "Set", "WeakMap", "WeakSet"];
+    var objects = {};
+
+    new_globals.forEach(function (new_global) {
+        objects[new_global] = global[new_global] || new Function();
+    });
+
+    var a = [];
+    [ Object, Array, Function, Number,
+      String, Boolean, Error, Math,
+      Date, RegExp, objects.Symbol, ArrayBuffer,
+      DataView, decodeURI, decodeURIComponent,
+      encodeURI, encodeURIComponent, eval, EvalError,
+      Float32Array, Float64Array, Int8Array, Int16Array,
+      Int32Array, isFinite, isNaN, JSON, objects.Map, parseFloat,
+      parseInt, objects.Promise, objects.Proxy, RangeError, ReferenceError,
+      objects.Reflect, objects.Set, SyntaxError, TypeError, Uint8Array,
+      Uint8ClampedArray, Uint16Array, Uint32Array, URIError,
+      objects.WeakMap, objects.WeakSet
+    ].forEach(function(ctor){
+        Object.getOwnPropertyNames(ctor).map(add);
+        if (ctor.prototype) {
+            Object.getOwnPropertyNames(ctor.prototype).map(add);
+        }
+    });
+    function add(name) {
+        push_uniq(a, name);
+    }
+    return a;
+}
+
+function mangle_properties(ast, options) {
+    options = defaults(options, {
+        reserved : null,
+        cache : null,
+        only_cache : false,
+        regex : null,
+        ignore_quoted : false,
+        debug : false
+    });
+
+    var reserved = options.reserved;
+    if (reserved == null)
+        reserved = find_builtins();
+
+    var cache = options.cache;
+    if (cache == null) {
+        cache = {
+            cname: -1,
+            props: new Dictionary()
+        };
+    }
+
+    var regex = options.regex;
+    var ignore_quoted = options.ignore_quoted;
+
+    // note debug is either false (disabled), or a string of the debug suffix to use (enabled).
+    // note debug may be enabled as an empty string, which is falsey. Also treat passing 'true'
+    // the same as passing an empty string.
+    var debug = (options.debug !== false);
+    var debug_name_suffix;
+    if (debug) {
+        debug_name_suffix = (options.debug === true ? "" : options.debug);
+    }
+
+    var names_to_mangle = [];
+    var unmangleable = [];
+    var ignored = {};
+
+    // step 1: find candidates to mangle
+    ast.walk(new TreeWalker(function(node){
+        if (node instanceof AST_ObjectKeyVal) {
+            add(node.key, ignore_quoted && node.quote);
+        }
+        else if (node instanceof AST_ObjectProperty) {
+            // setter or getter, since KeyVal is handled above
+            add(node.key.name);
+        }
+        else if (node instanceof AST_Dot) {
+            add(node.property);
+        }
+        else if (node instanceof AST_Sub) {
+            addStrings(node.property, ignore_quoted);
+        }
+        else if (node instanceof AST_ConciseMethod) {
+            add(node.name.name);
+        }
+    }));
+
+    // step 2: transform the tree, renaming properties
+    return ast.transform(new TreeTransformer(function(node){
+        if (node instanceof AST_ObjectKeyVal) {
+            if (!(ignore_quoted && node.quote))
+                node.key = mangle(node.key);
+        }
+        else if (node instanceof AST_ObjectProperty) {
+            // setter or getter
+            node.key.name = mangle(node.key.name);
+        }
+        else if (node instanceof AST_Dot) {
+            node.property = mangle(node.property);
+        }
+        else if (node instanceof AST_Sub) {
+            if (!ignore_quoted)
+                node.property = mangleStrings(node.property);
+        }
+        else if (node instanceof AST_ConciseMethod) {
+            if (should_mangle(node.name.name)) {
+                node.name.name = mangle(node.name.name);
+            }
+        }
+        // else if (node instanceof AST_String) {
+        //     if (should_mangle(node.value)) {
+        //         AST_Node.warn(
+        //             "Found \"{prop}\" property candidate for mangling in an arbitrary string [{file}:{line},{col}]", {
+        //                 file : node.start.file,
+        //                 line : node.start.line,
+        //                 col  : node.start.col,
+        //                 prop : node.value
+        //             }
+        //         );
+        //     }
+        // }
+    }));
+
+    // only function declarations after this line
+
+    function can_mangle(name) {
+        if (!is_identifier(name)) return false;
+        if (unmangleable.indexOf(name) >= 0) return false;
+        if (reserved.indexOf(name) >= 0) return false;
+        if (options.only_cache) {
+            return cache.props.has(name);
+        }
+        if (/^[0-9.]+$/.test(name)) return false;
+        return true;
+    }
+
+    function should_mangle(name) {
+        if (ignore_quoted && name in ignored) return false;
+        if (regex && !regex.test(name)) return false;
+        if (reserved.indexOf(name) >= 0) return false;
+        return cache.props.has(name)
+            || names_to_mangle.indexOf(name) >= 0;
+    }
+
+    function add(name, ignore) {
+        if (ignore) {
+            ignored[name] = true;
+            return;
+        }
+
+        if (can_mangle(name))
+            push_uniq(names_to_mangle, name);
+
+        if (!should_mangle(name)) {
+            push_uniq(unmangleable, name);
+        }
+    }
+
+    function mangle(name) {
+        if (!should_mangle(name)) {
+            return name;
+        }
+
+        var mangled = cache.props.get(name);
+        if (!mangled) {
+            if (debug) {
+                // debug mode: use a prefix and suffix to preserve readability, e.g. o.foo -> o._$foo$NNN_.
+                var debug_mangled = "_$" + name + "$" + debug_name_suffix + "_";
+
+                if (can_mangle(debug_mangled) && !(ignore_quoted && debug_mangled in ignored)) {
+                    mangled = debug_mangled;
+                }
+            }
+
+            // either debug mode is off, or it is on and we could not use the mangled name
+            if (!mangled) {
+                // note can_mangle() does not check if the name collides with the 'ignored' set
+                // (filled with quoted properties when ignore_quoted set). Make sure we add this
+                // check so we don't collide with a quoted name.
+                do {
+                    mangled = base54(++cache.cname);
+                } while (!can_mangle(mangled) || (ignore_quoted && mangled in ignored));
+            }
+
+            cache.props.set(name, mangled);
+        }
+        return mangled;
+    }
+
+    function addStrings(node, ignore) {
+        var out = {};
+        try {
+            (function walk(node){
+                node.walk(new TreeWalker(function(node){
+                    if (node instanceof AST_Seq) {
+                        walk(node.cdr);
+                        return true;
+                    }
+                    if (node instanceof AST_String) {
+                        add(node.value, ignore);
+                        return true;
+                    }
+                    if (node instanceof AST_Conditional) {
+                        walk(node.consequent);
+                        walk(node.alternative);
+                        return true;
+                    }
+                    throw out;
+                }));
+            })(node);
+        } catch(ex) {
+            if (ex !== out) throw ex;
+        }
+    }
+
+    function mangleStrings(node) {
+        return node.transform(new TreeTransformer(function(node){
+            if (node instanceof AST_Seq) {
+                node.cdr = mangleStrings(node.cdr);
+            }
+            else if (node instanceof AST_String) {
+                node.value = mangle(node.value);
+            }
+            else if (node instanceof AST_Conditional) {
+                node.consequent = mangleStrings(node.consequent);
+                node.alternative = mangleStrings(node.alternative);
+            }
+            return node;
+        }));
+    }
+
+}

lib/scope.js

@@ -49,83 +49,141 @@ function SymbolDef(scope, index, orig) {
     this.scope = scope;
     this.references = [];
     this.global = false;
+    this.export = false;
     this.mangled_name = null;
+    this.object_destructuring_arg = false;
     this.undeclared = false;
-    this.constant = false;
     this.index = index;
+    this.id = SymbolDef.next_id++;
 };
 
+SymbolDef.next_id = 1;
+
 SymbolDef.prototype = {
     unmangleable: function(options) {
-        return (this.global && !(options && options.toplevel))
+        if (!options) options = {};
+
+        return (this.global && !options.toplevel)
+            || this.export
+            || this.object_destructuring_arg
             || this.undeclared
-            || (!(options && options.eval) && (this.scope.uses_eval || this.scope.uses_with));
+            || (!options.eval && (this.scope.uses_eval || this.scope.uses_with))
+            || (options.keep_fnames
+                && (this.orig[0] instanceof AST_SymbolLambda
+                    || this.orig[0] instanceof AST_SymbolDefun))
+            || this.orig[0] instanceof AST_SymbolMethod
+            || (options.keep_classnames
+                && (this.orig[0] instanceof AST_SymbolClass
+                    || this.orig[0] instanceof AST_SymbolDefClass));
     },
     mangle: function(options) {
-        if (!this.mangled_name && !this.unmangleable(options)) {
+        var cache = options.cache && options.cache.props;
+        if (this.global && cache && cache.has(this.name)) {
+            this.mangled_name = cache.get(this.name);
+        }
+        else if (!this.mangled_name && !this.unmangleable(options)) {
             var s = this.scope;
-            if (this.orig[0] instanceof AST_SymbolLambda && !options.screw_ie8)
+            if (!options.screw_ie8 && this.orig[0] instanceof AST_SymbolLambda)
                 s = s.parent_scope;
-            this.mangled_name = s.next_mangled(options);
+            this.mangled_name = s.next_mangled(options, this);
+            if (this.global && cache) {
+                cache.set(this.name, this.mangled_name);
+            }
         }
     }
 };
 
-AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
-    // This does what ast_add_scope did in UglifyJS v1.
-    //
-    // Part of it could be done at parse time, but it would complicate
-    // the parser (and it's already kinda complex).  It's also worth
-    // having it separated because we might need to call it multiple
-    // times on the same tree.
+AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
+    options = defaults(options, {
+        screw_ie8: true,
+        cache: null
+    });
 
     // pass 1: setup scope chaining and handle definitions
     var self = this;
     var scope = self.parent_scope = null;
     var labels = new Dictionary();
-    var nesting = 0;
+    var defun = null;
+    var in_destructuring = null;
+    var in_export = false;
+    var in_block = 0;
     var tw = new TreeWalker(function(node, descend){
+        if (node.is_block_scope()) {
+            var save_scope = scope;
+            scope = new AST_Scope(node);
+            scope.init_scope_vars();
+            scope.parent_scope = save_scope;
+            if (!(node instanceof AST_Scope)) {
+                scope.uses_with = save_scope.uses_with;
+                scope.uses_eval = save_scope.uses_eval;
+                scope.directives = save_scope.directives;
+            }
+            descend();
+            scope = save_scope;
+            return true;
+        }
+        if (node instanceof AST_Destructuring && node.is_array === false) {
+            in_destructuring = node;  // These don't nest
+            descend();
+            in_destructuring = null;
+            return true;
+        }
         if (node instanceof AST_Scope) {
-            node.init_scope_vars(nesting);
+            node.init_scope_vars();
             var save_scope = node.parent_scope = scope;
+            var save_defun = defun;
             var save_labels = labels;
-            ++nesting;
-            scope = node;
+            defun = scope = node;
             labels = new Dictionary();
             descend();
-            labels = save_labels;
             scope = save_scope;
-            --nesting;
+            defun = save_defun;
+            labels = save_labels;
             return true;        // don't descend again in TreeWalker
         }
-        if (node instanceof AST_Directive) {
-            node.scope = scope;
-            push_uniq(scope.directives, node.value);
+        if (node instanceof AST_Export) {
+            in_export = true;
+            descend();
+            in_export = false;
             return true;
         }
+        if (node instanceof AST_BlockStatement
+            || node instanceof AST_Switch
+            || node instanceof AST_Try
+            || node instanceof AST_Catch
+            || node instanceof AST_Finally) {
+            in_block++;
+            descend();
+            in_block--;
+            return true;
+        }
+        if (node instanceof AST_LabeledStatement) {
+            var l = node.label;
+            if (labels.has(l.name)) {
+                throw new Error(string_template("Label {name} defined twice", l));
+            }
+            labels.set(l.name, l);
+            descend();
+            labels.del(l.name);
+            return true;        // no descend again
+        }
         if (node instanceof AST_With) {
             for (var s = scope; s; s = s.parent_scope)
                 s.uses_with = true;
             return;
         }
-        if (node instanceof AST_LabeledStatement) {
-            var l = node.label;
-            if (labels.has(l.name))
-                throw new Error(string_template("Label {name} defined twice", l));
-            labels.set(l.name, l);
-            descend();
-            labels.del(l.name);
-            return true;        // no descend again
-        }
         if (node instanceof AST_Symbol) {
             node.scope = scope;
         }
+        if (node instanceof AST_SymbolFunarg) {
+            node.object_destructuring_arg = !!in_destructuring;
+        }
         if (node instanceof AST_Label) {
             node.thedef = node;
-            node.init_scope_vars();
+            node.references = [];
         }
         if (node instanceof AST_SymbolLambda) {
-            scope.def_function(node);
+            defun.def_function(node, in_export, in_block);
         }
         else if (node instanceof AST_SymbolDefun) {
             // Careful here, the scope where this should be defined is
@@ -133,24 +191,33 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             // scope when we encounter the AST_Defun node (which is
             // instanceof AST_Scope) but we get to the symbol a bit
             // later.
-            (node.scope = scope.parent_scope).def_function(node);
+            var parent_lambda = defun.parent_scope;
+            while (parent_lambda.is_block_scope()) {
+                parent_lambda = parent_lambda.parent_scope;
+            }
+            (node.scope = parent_lambda).def_function(node, in_export, in_block);
+        }
+        else if (node instanceof AST_SymbolClass) {
+            defun.def_variable(node, in_export, in_block);
+        }
+        else if (node instanceof AST_SymbolImport) {
+            scope.def_variable(node, in_export, in_block);
+        }
+        else if (node instanceof AST_SymbolDefClass) {
+            // This deals with the name of the class being available
+            // inside the class.
+            (node.scope = defun.parent_scope).def_function(node, in_export, in_block);
         }
         else if (node instanceof AST_SymbolVar
-                 || node instanceof AST_SymbolConst) {
-            var def = scope.def_variable(node);
-            def.constant = node instanceof AST_SymbolConst;
-            def.init = tw.parent().value;
+            || node instanceof AST_SymbolLet
+            || node instanceof AST_SymbolConst) {
+            var def = ((node instanceof AST_SymbolBlockDeclaration) ? scope : defun).def_variable(node, in_export, in_block);
+            def.destructuring = in_destructuring;
         }
         else if (node instanceof AST_SymbolCatch) {
-            // XXX: this is wrong according to ECMA-262 (12.4).  the
-            // `catch` argument name should be visible only inside the
-            // catch block.  For a quick fix AST_Catch should inherit
-            // from AST_Scope.  Keeping it this way because of IE,
-            // which doesn't obey the standard. (it introduces the
-            // identifier in the enclosing scope)
-            scope.def_variable(node);
+            scope.def_variable(node, in_export, in_block);
         }
-        if (node instanceof AST_LabelRef) {
+        else if (node instanceof AST_LabelRef) {
             var sym = labels.get(node.name);
             if (!sym) throw new Error(string_template("Undefined label {name} [{line},{col}]", {
                 name: node.name,
@@ -164,6 +231,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
 
     // pass 2: find back references and eval
     var func = null;
+    var cls = null;
     var globals = self.globals = new Dictionary();
     var tw = new TreeWalker(function(node, descend){
         if (node instanceof AST_Lambda) {
@@ -173,42 +241,75 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             func = prev_func;
             return true;
         }
-        if (node instanceof AST_LabelRef) {
-            node.reference();
+        if (node instanceof AST_Class) {
+            var prev_cls = cls;
+            cls = node;
+            descend();
+            cls = prev_cls;
+            return true;
+        }
+        if (node instanceof AST_LoopControl && node.label) {
+            node.label.thedef.references.push(node);
             return true;
         }
         if (node instanceof AST_SymbolRef) {
             var name = node.name;
-            var sym = node.scope.find_variable(name);
-            if (!sym) {
-                var g;
-                if (globals.has(name)) {
-                    g = globals.get(name);
-                } else {
-                    g = new SymbolDef(self, globals.size(), node);
-                    g.undeclared = true;
-                    globals.set(name, g);
+            if (name == "eval" && tw.parent() instanceof AST_Call) {
+                for (var s = node.scope; s && !s.uses_eval; s = s.parent_scope) {
+                    s.uses_eval = true;
                 }
-                node.thedef = g;
-                if (name == "eval" && tw.parent() instanceof AST_Call) {
-                    for (var s = node.scope; s && !s.uses_eval; s = s.parent_scope)
-                        s.uses_eval = true;
-                }
-                if (name == "arguments") {
-                    func.uses_arguments = true;
-                }
-            } else {
-                node.thedef = sym;
             }
-            node.reference();
+            var sym = node.scope.find_variable(name);
+            if (node.scope instanceof AST_Lambda && name == "arguments") {
+                node.scope.uses_arguments = true;
+            }
+            if (!sym) {
+                sym = self.def_global(node);
+            }
+            node.thedef = sym;
+            node.reference(options);
             return true;
         }
     });
     self.walk(tw);
+
+    // pass 3: fix up any scoping issue with IE8
+    if (!options.screw_ie8) {
+        self.walk(new TreeWalker(function(node, descend) {
+            if (node instanceof AST_SymbolCatch) {
+                var name = node.name;
+                var refs = node.thedef.references;
+                var scope = node.thedef.scope.parent_scope.parent_scope;
+                var def = scope.find_variable(name) || self.globals.get(name) || scope.def_variable(node);
+                refs.forEach(function(ref) {
+                    ref.thedef = def;
+                    ref.reference(options);
+                });
+                node.thedef = def;
+                return true;
+            }
+        }));
+    }
+
+    if (options.cache) {
+        this.cname = options.cache.cname;
+    }
 });
 
-AST_Scope.DEFMETHOD("init_scope_vars", function(nesting){
-    this.directives = [];     // contains the directives defined in this scope, i.e. "use strict"
+AST_Toplevel.DEFMETHOD("def_global", function(node){
+    var globals = this.globals, name = node.name;
+    if (globals.has(name)) {
+        return globals.get(name);
+    } else {
+        var g = new SymbolDef(this, globals.size(), node);
+        g.undeclared = true;
+        g.global = true;
+        globals.set(name, g);
+        return g;
+    }
+});
+
+AST_Scope.DEFMETHOD("init_scope_vars", function(){
     this.variables = new Dictionary(); // map name to AST_SymbolVar (variables defined in this scope; includes functions)
     this.functions = new Dictionary(); // map name to AST_SymbolDefun (functions defined in this scope)
     this.uses_with = false;   // will be set to true if this or some nested scope uses the `with` statement
@@ -216,36 +317,48 @@ AST_Scope.DEFMETHOD("init_scope_vars", function(nesting){
     this.parent_scope = null; // the parent scope
     this.enclosed = [];       // a list of variables from this or outer scope(s) that are referenced from this or inner scopes
     this.cname = -1;          // the current index for mangling functions/variables
-    this.nesting = nesting;   // the nesting level of this scope (0 means toplevel)
 });
 
-AST_Scope.DEFMETHOD("strict", function(){
-    return this.has_directive("use strict");
+AST_Node.DEFMETHOD("is_block_scope", function(){
+    return false; // Behaviour will be overridden by AST_Block
+});
+
+AST_Block.DEFMETHOD("is_block_scope", function(){
+    return (
+        !(this instanceof AST_Lambda) &&
+        !(this instanceof AST_Toplevel) &&
+        !(this instanceof AST_Class) &&
+        !(this instanceof AST_SwitchBranch)
+    );
+});
+
+AST_IterationStatement.DEFMETHOD("is_block_scope", function(){
+     return true;
 });
 
 AST_Lambda.DEFMETHOD("init_scope_vars", function(){
     AST_Scope.prototype.init_scope_vars.apply(this, arguments);
     this.uses_arguments = false;
+
+    var symbol = new AST_VarDef({ name: "arguments", start: this.start, end: this.end });
+    var def = new SymbolDef(this, this.variables.size(), symbol);
+    this.variables.set(symbol.name, def);
 });
 
-AST_SymbolRef.DEFMETHOD("reference", function() {
+AST_SymbolRef.DEFMETHOD("reference", function(options) {
     var def = this.definition();
     def.references.push(this);
     var s = this.scope;
     while (s) {
         push_uniq(s.enclosed, def);
+        if (options.keep_fnames) {
+            s.functions.each(function(d) {
+                push_uniq(def.scope.enclosed, d);
+            });
+        }
         if (s === def.scope) break;
         s = s.parent_scope;
     }
-    this.frame = this.scope.nesting - def.scope.nesting;
-});
-
-AST_Label.DEFMETHOD("init_scope_vars", function(){
-    this.references = [];
-});
-
-AST_LabelRef.DEFMETHOD("reference", function(){
-    this.thedef.references.push(this);
 });
 
 AST_Scope.DEFMETHOD("find_variable", function(name){
@@ -254,21 +367,24 @@ AST_Scope.DEFMETHOD("find_variable", function(name){
         || (this.parent_scope && this.parent_scope.find_variable(name));
 });
 
-AST_Scope.DEFMETHOD("has_directive", function(value){
-    return this.parent_scope && this.parent_scope.has_directive(value)
-        || (this.directives.indexOf(value) >= 0 ? this : null);
+AST_Scope.DEFMETHOD("def_function", function(symbol, in_export, in_block){
+    this.functions.set(symbol.name, this.def_variable(symbol, in_export, in_block));
 });
 
-AST_Scope.DEFMETHOD("def_function", function(symbol){
-    this.functions.set(symbol.name, this.def_variable(symbol));
-});
-
-AST_Scope.DEFMETHOD("def_variable", function(symbol){
+AST_Scope.DEFMETHOD("def_variable", function(symbol, in_export, in_block){
     var def;
     if (!this.variables.has(symbol.name)) {
         def = new SymbolDef(this, this.variables.size(), symbol);
         this.variables.set(symbol.name, def);
-        def.global = !this.parent_scope;
+        def.object_destructuring_arg = symbol.object_destructuring_arg;
+        if (in_export) {
+            def.export = true;
+        }
+        if (in_block && symbol instanceof AST_SymbolBlockDeclaration) {
+            def.global = false;
+        } else {
+            def.global = !this.parent_scope;
+        }
     } else {
         def = this.variables.get(symbol.name);
         def.orig.push(symbol);
@@ -281,6 +397,11 @@ AST_Scope.DEFMETHOD("next_mangled", function(options){
     out: while (true) {
         var m = base54(++this.cname);
         if (!is_identifier(m)) continue; // skip over "do"
+
+        // https://github.com/mishoo/UglifyJS2/issues/242 -- do not
+        // shadow a name excepted from mangling.
+        if (options.except.indexOf(m) >= 0) continue;
+
         // we must ensure that the mangled name does not shadow a name
         // from some parent scope that is referenced in this or in
         // inner scopes.
@@ -293,13 +414,26 @@ AST_Scope.DEFMETHOD("next_mangled", function(options){
     }
 });
 
-AST_Scope.DEFMETHOD("references", function(sym){
-    if (sym instanceof AST_Symbol) sym = sym.definition();
-    return this.enclosed.indexOf(sym) < 0 ? null : sym;
+AST_Function.DEFMETHOD("next_mangled", function(options, def){
+    // #179, #326
+    // in Safari strict mode, something like (function x(x){...}) is a syntax error;
+    // a function expression's argument cannot shadow the function expression's name
+
+    var tricky_def = def.orig[0] instanceof AST_SymbolFunarg && this.name && this.name.definition();
+
+    // the function's mangled_name is null when keep_fnames is true
+    var tricky_name = tricky_def ? tricky_def.mangled_name || tricky_def.name : null;
+
+    while (true) {
+        var name = AST_Lambda.prototype.next_mangled.call(this, options, def);
+        if (!tricky_name || tricky_name != name)
+            return name;
+    }
 });
 
 AST_Symbol.DEFMETHOD("unmangleable", function(options){
-    return this.definition().unmangleable(options);
+    var def = this.definition();
+    return def && def.unmangleable(options);
 });
 
 // property accessors are not mangleable
@@ -339,22 +473,37 @@ AST_Symbol.DEFMETHOD("global", function(){
 
 AST_Toplevel.DEFMETHOD("_default_mangler_options", function(options){
     return defaults(options, {
-        except   : [],
-        eval     : false,
-        sort     : false,
-        toplevel : false,
-        screw_ie8 : false
+        except      : [],
+        eval        : false,
+        sort        : false, // Ignored. Flag retained for backwards compatibility.
+        toplevel    : false,
+        screw_ie8   : true,
+        keep_fnames : false,
+        keep_classnames : false
     });
 });
 
 AST_Toplevel.DEFMETHOD("mangle_names", function(options){
     options = this._default_mangler_options(options);
+
+    // Never mangle arguments
+    options.except.push('arguments');
+
     // We only need to mangle declaration nodes.  Special logic wired
     // into the code generator will display the mangled name if it's
     // present (and for AST_SymbolRef-s it'll use the mangled name of
     // the AST_SymbolDeclaration that it points to).
     var lname = -1;
     var to_mangle = [];
+
+    if (options.cache) {
+        this.globals.each(function(symbol){
+            if (options.except.indexOf(symbol.name) < 0) {
+                to_mangle.push(symbol);
+            }
+        });
+    }
+
     var tw = new TreeWalker(function(node, descend){
         if (node instanceof AST_LabeledStatement) {
             // lname is incremented when we get to the AST_Label
@@ -370,9 +519,6 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options){
                     a.push(symbol);
                 }
             });
-            if (options.sort) a.sort(function(a, b){
-                return b.references.length - a.references.length;
-            });
             to_mangle.push.apply(to_mangle, a);
             return;
         }
@@ -382,9 +528,23 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options){
             node.mangled_name = name;
             return true;
         }
+        var mangle_with_block_scope =
+            (options.screw_ie8 && node instanceof AST_SymbolCatch) ||
+            node instanceof AST_SymbolBlockDeclaration;
+        if (mangle_with_block_scope) {
+            to_mangle.push(node.definition());
+            return;
+        }
     });
     this.walk(tw);
-    to_mangle.forEach(function(def){ def.mangle(options) });
+    to_mangle.forEach(function(def){
+        if (def.destructuring && !def.destructuring.is_array) return;
+        def.mangle(options);
+    });
+
+    if (options.cache) {
+        options.cache.cname = this.cname;
+    }
 });
 
 AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options){
@@ -431,21 +591,27 @@ AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options){
         else if (node instanceof AST_With)
             base54.consider("with");
         else if (node instanceof AST_ObjectSetter)
-            base54.consider("set" + node.key);
+            base54.consider("set" + (typeof node.key === "string" ? node.key : ""));
         else if (node instanceof AST_ObjectGetter)
-            base54.consider("get" + node.key);
-        else if (node instanceof AST_ObjectKeyVal)
+            base54.consider("get" + (typeof node.key === "string" ? node.key : ""));
+        else if (node instanceof AST_ObjectKeyVal && typeof node.key === "string")
+            base54.consider(node.key);
+        else if (node instanceof AST_ConciseMethod && typeof node.key === "string")
             base54.consider(node.key);
         else if (node instanceof AST_New)
             base54.consider("new");
         else if (node instanceof AST_This)
             base54.consider("this");
+        else if (node instanceof AST_Super)
+            base54.consider("super");
         else if (node instanceof AST_Try)
             base54.consider("try");
         else if (node instanceof AST_Catch)
             base54.consider("catch");
         else if (node instanceof AST_Finally)
             base54.consider("finally");
+        else if (node instanceof AST_Yield)
+            base54.consider("yield");
         else if (node instanceof AST_Symbol && node.unmangleable(options))
             base54.consider(node.name);
         else if (node instanceof AST_Unary || node instanceof AST_Binary)
@@ -484,7 +650,9 @@ var base54 = (function() {
     base54.freq = function(){ return frequency };
     function base54(num) {
         var ret = "", base = 54;
+        num++;
         do {
+            num--;
             ret += String.fromCharCode(chars[num % base]);
             num = Math.floor(num / base);
             base = 64;
@@ -545,6 +713,7 @@ AST_Toplevel.DEFMETHOD("scope_warnings", function(options){
         }
         if (options.unreferenced
             && (node instanceof AST_SymbolDeclaration || node instanceof AST_Label)
+            && !(node instanceof AST_SymbolCatch)
             && node.unreferenced()) {
             AST_Node.warn("{type} {name} is declared but not referenced [{file}:{line},{col}]", {
                 type: node instanceof AST_Label ? "Label" : "Symbol",

lib/sourcemap.js

@@ -49,26 +49,42 @@ function SourceMap(options) {
         file : null,
         root : null,
         orig : null,
+
+        orig_line_diff : 0,
+        dest_line_diff : 0,
     });
     var generator = new MOZ_SourceMap.SourceMapGenerator({
         file       : options.file,
         sourceRoot : options.root
     });
     var orig_map = options.orig && new MOZ_SourceMap.SourceMapConsumer(options.orig);
+
+    if (orig_map && Array.isArray(options.orig.sources)) {
+        orig_map._sources.toArray().forEach(function(source) {
+            var sourceContent = orig_map.sourceContentFor(source, true);
+            if (sourceContent) {
+                generator.setSourceContent(source, sourceContent);
+            }
+        });
+    }
+
     function add(source, gen_line, gen_col, orig_line, orig_col, name) {
         if (orig_map) {
             var info = orig_map.originalPositionFor({
                 line: orig_line,
                 column: orig_col
             });
+            if (info.source === null) {
+                return;
+            }
             source = info.source;
             orig_line = info.line;
             orig_col = info.column;
-            name = info.name;
+            name = info.name || name;
         }
         generator.addMapping({
-            generated : { line: gen_line, column: gen_col },
-            original  : { line: orig_line, column: orig_col },
+            generated : { line: gen_line + options.dest_line_diff, column: gen_col },
+            original  : { line: orig_line + options.orig_line_diff, column: orig_col },
             source    : source,
             name      : name
         });
@@ -76,6 +92,6 @@ function SourceMap(options) {
     return {
         add        : add,
         get        : function() { return generator },
-        toString   : function() { return generator.toString() }
+        toString   : function() { return JSON.stringify(generator.toJSON()); }
     };
 };

lib/transform.js

@@ -44,7 +44,6 @@
 "use strict";
 
 // Tree transformer helpers.
-// XXX: eventually I should refactor the compressor to use this infrastructure.
 
 function TreeTransformer(before, after) {
     TreeWalker.call(this);
@@ -65,13 +64,13 @@ TreeTransformer.prototype = new TreeWalker;
                     x = this;
                     descend(x, tw);
                 } else {
-                    tw.stack[tw.stack.length - 1] = x = this.clone();
+                    tw.stack[tw.stack.length - 1] = x = this;
                     descend(x, tw);
                     y = tw.after(x, in_list);
                     if (y !== undefined) x = y;
                 }
             }
-            tw.pop();
+            tw.pop(this);
             return x;
         });
     };
@@ -160,13 +159,22 @@ TreeTransformer.prototype = new TreeWalker;
     });
 
     _(AST_VarDef, function(self, tw){
+        self.name = self.name.transform(tw);
         if (self.value) self.value = self.value.transform(tw);
     });
 
+    _(AST_Destructuring, function(self, tw) {
+        self.names = do_list(self.names, tw);
+    });
+
     _(AST_Lambda, function(self, tw){
         if (self.name) self.name = self.name.transform(tw);
         self.argnames = do_list(self.argnames, tw);
-        self.body = do_list(self.body, tw);
+        if (self.body instanceof AST_Node) {
+            self.body = self.body.transform(tw);
+        } else {
+            self.body = do_list(self.body, tw);
+        }
     });
 
     _(AST_Call, function(self, tw){
@@ -188,6 +196,10 @@ TreeTransformer.prototype = new TreeWalker;
         self.property = self.property.transform(tw);
     });
 
+    _(AST_Yield, function(self, tw){
+        if (self.expression) self.expression = self.expression.transform(tw);
+    });
+
     _(AST_Unary, function(self, tw){
         self.expression = self.expression.transform(tw);
     });
@@ -212,7 +224,32 @@ TreeTransformer.prototype = new TreeWalker;
     });
 
     _(AST_ObjectProperty, function(self, tw){
+        if (self.key instanceof AST_Node) {
+            self.key = self.key.transform(tw);
+        }
         self.value = self.value.transform(tw);
     });
 
+    _(AST_Class, function(self, tw){
+        if (self.name) self.name = self.name.transform(tw);
+        if (self.extends) self.extends = self.extends.transform(tw);
+        self.properties = do_list(self.properties, tw);
+    });
+
+    _(AST_Expansion, function(self, tw){
+        self.expression = self.expression.transform(tw);
+    });
+
+    _(AST_TemplateString, function(self, tw) {
+        for (var i = 0; i < self.segments.length; i++) {
+            if (!(self.segments[i] instanceof AST_TemplateSegment)) {
+                self.segments[i] = self.segments[i].transform(tw);
+            }
+        }
+    });
+
+    _(AST_PrefixedTemplateString, function(self, tw) {
+        self.template_string = self.template_string.transform(tw);
+    });
+
 })();

lib/utils.js

@@ -59,10 +59,7 @@ function characters(str) {
 };
 
 function member(name, array) {
-    for (var i = array.length; --i >= 0;)
-        if (array[i] == name)
-            return true;
-    return false;
+    return array.indexOf(name) >= 0;
 };
 
 function find_if(func, array) {
@@ -81,31 +78,59 @@ function repeat_string(str, i) {
     return d;
 };
 
+function configure_error_stack(fn) {
+    Object.defineProperty(fn.prototype, "stack", {
+        get: function() {
+            var err = new Error(this.message);
+            err.name = this.name;
+            try {
+                throw err;
+            } catch(e) {
+                return e.stack;
+            }
+        }
+    });
+}
+
 function DefaultsError(msg, defs) {
-    this.msg = msg;
+    this.message = msg;
     this.defs = defs;
 };
+DefaultsError.prototype = Object.create(Error.prototype);
+DefaultsError.prototype.constructor = DefaultsError;
+DefaultsError.prototype.name = "DefaultsError";
+configure_error_stack(DefaultsError);
+
+DefaultsError.croak = function(msg, defs) {
+    throw new DefaultsError(msg, defs);
+};
 
 function defaults(args, defs, croak) {
     if (args === true)
         args = {};
     var ret = args || {};
-    if (croak) for (var i in ret) if (ret.hasOwnProperty(i) && !defs.hasOwnProperty(i))
-        throw new DefaultsError("`" + i + "` is not a supported option", defs);
-    for (var i in defs) if (defs.hasOwnProperty(i)) {
-        ret[i] = (args && args.hasOwnProperty(i)) ? args[i] : defs[i];
+    if (croak) for (var i in ret) if (HOP(ret, i) && !HOP(defs, i))
+        DefaultsError.croak("`" + i + "` is not a supported option", defs);
+    for (var i in defs) if (HOP(defs, i)) {
+        ret[i] = (args && HOP(args, i)) ? args[i] : defs[i];
     }
     return ret;
 };
 
 function merge(obj, ext) {
-    for (var i in ext) if (ext.hasOwnProperty(i)) {
+    var count = 0;
+    for (var i in ext) if (HOP(ext, i)) {
         obj[i] = ext[i];
+        count++;
     }
-    return obj;
+    return count;
 };
 
-function noop() {};
+function noop() {}
+function return_false() { return false; }
+function return_true() { return true; }
+function return_this() { return this; }
+function return_null() { return null; }
 
 var MAP = (function(){
     function MAP(a, f, backwards) {
@@ -141,7 +166,7 @@ var MAP = (function(){
             }
         }
         else {
-            for (i in a) if (a.hasOwnProperty(i)) if (doit()) break;
+            for (i in a) if (HOP(a, i)) if (doit()) break;
         }
         return top.concat(ret);
     };
@@ -162,7 +187,7 @@ function push_uniq(array, el) {
 
 function string_template(text, props) {
     return text.replace(/\{(.+?)\}/g, function(str, p){
-        return props[p];
+        return props && props[p];
     });
 };
 
@@ -221,10 +246,19 @@ function makePredicate(words) {
             }
         cats.push([words[i]]);
     }
+    function quote(word) {
+        return JSON.stringify(word).replace(/[\u2028\u2029]/g, function(s) {
+            switch (s) {
+                case "\u2028": return "\\u2028";
+                case "\u2029": return "\\u2029";
+            }
+            return s;
+        });
+    }
     function compareTo(arr) {
-        if (arr.length == 1) return f += "return str === " + JSON.stringify(arr[0]) + ";";
+        if (arr.length == 1) return f += "return str === " + quote(arr[0]) + ";";
         f += "switch(str){";
-        for (var i = 0; i < arr.length; ++i) f += "case " + JSON.stringify(arr[i]) + ":";
+        for (var i = 0; i < arr.length; ++i) f += "case " + quote(arr[i]) + ":";
         f += "return true}return false;";
     }
     // When there are more than three length categories, an outer
@@ -245,6 +279,13 @@ function makePredicate(words) {
     return new Function("str", f);
 };
 
+function all(array, predicate) {
+    for (var i = array.length; --i >= 0;)
+        if (!predicate(array[i]))
+            return false;
+    return true;
+};
+
 function Dictionary() {
     this._values = Object.create(null);
     this._size = 0;
@@ -284,5 +325,38 @@ Dictionary.prototype = {
         for (var i in this._values)
             ret.push(f(this._values[i], i.substr(1)));
         return ret;
-    }
+    },
+    toObject: function() { return this._values }
 };
+Dictionary.fromObject = function(obj) {
+    var dict = new Dictionary();
+    dict._size = merge(dict._values, obj);
+    return dict;
+};
+
+function HOP(obj, prop) {
+    return Object.prototype.hasOwnProperty.call(obj, prop);
+}
+
+// return true if the node at the top of the stack (that means the
+// innermost node in the current output) is lexically the first in
+// a statement.
+function first_in_statement(stack) {
+    var node = stack.parent(-1);
+    for (var i = 0, p; p = stack.parent(i); i++) {
+        if (p instanceof AST_Statement && p.body === node)
+            return true;
+        if ((p instanceof AST_Seq           && p.car === node        ) ||
+            (p instanceof AST_Call          && p.expression === node && !(p instanceof AST_New) ) ||
+            (p instanceof AST_Dot           && p.expression === node ) ||
+            (p instanceof AST_Sub           && p.expression === node ) ||
+            (p instanceof AST_Conditional   && p.condition === node  ) ||
+            (p instanceof AST_Binary        && p.left === node       ) ||
+            (p instanceof AST_UnaryPostfix  && p.expression === node ))
+        {
+            node = p;
+        } else {
+            return false;
+        }
+    }
+}

package.json

@@ -1,26 +1,53 @@
 {
-    "name": "uglify-js",
-    "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
-    "homepage": "http://lisperator.net/uglifyjs",
-    "main": "tools/node.js",
-    "version": "2.3.2",
-    "engines": { "node" : ">=0.4.0" },
-    "maintainers": [{
-        "name": "Mihai Bazon",
-        "email": "mihai.bazon@gmail.com",
-        "web": "http://lisperator.net/"
-    }],
-    "repositories": [{
-        "type": "git",
-        "url": "https://github.com/mishoo/UglifyJS2.git"
-    }],
-    "dependencies": {
-        "async"      : "~0.2.6",
-        "source-map" : "~0.1.7",
-        "optimist"   : "~0.3.5"
-    },
-    "bin": {
-        "uglifyjs" : "bin/uglifyjs"
-    },
-    "scripts": {"test": "node test/run-tests.js"}
+  "name": "uglify-js",
+  "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
+  "homepage": "http://lisperator.net/uglifyjs",
+  "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
+  "license": "BSD-2-Clause",
+  "version": "2.8.14",
+  "engines": {
+    "node": ">=0.8.0"
+  },
+  "maintainers": [
+    "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)"
+  ],
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/mishoo/UglifyJS2.git"
+  },
+  "bugs": {
+    "url": "https://github.com/mishoo/UglifyJS2/issues"
+  },
+  "main": "tools/node.js",
+  "bin": {
+    "uglifyjs": "bin/uglifyjs"
+  },
+  "files": [
+    "bin",
+    "lib",
+    "tools",
+    "LICENSE"
+  ],
+  "dependencies": {
+    "source-map": "~0.5.1",
+    "uglify-to-browserify": "~1.0.0",
+    "yargs": "~3.10.0"
+  },
+  "devDependencies": {
+    "acorn": "~0.6.0",
+    "escodegen": "~1.3.3",
+    "esfuzz": "~0.3.1",
+    "estraverse": "~1.5.1",
+    "mocha": "~2.3.4"
+  },
+  "browserify": {
+    "transform": [
+      "uglify-to-browserify"
+    ]
+  },
+  "scripts": {
+    "shrinkwrap": "rm ./npm-shrinkwrap.json; rm -rf ./node_modules; npm i && npm shrinkwrap && npm outdated",
+    "test": "node test/run-tests.js"
+  },
+  "keywords": ["uglify", "uglify-js", "minify", "minifier"]
 }

test/benchmark.js

@@ -0,0 +1,80 @@
+#! /usr/bin/env node
+// -*- js -*-
+
+"use strict";
+
+var createHash = require("crypto").createHash;
+var fork = require("child_process").fork;
+var args = process.argv.slice(2);
+if (!args.length) {
+    args.push("-mc", "warnings=false");
+}
+args.push("--stats");
+var urls = [
+    "https://code.jquery.com/jquery-3.1.1.js",
+    "https://code.angularjs.org/1.6.1/angular.js",
+    "https://cdnjs.cloudflare.com/ajax/libs/mathjs/3.9.0/math.js",
+    "https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.js",
+    "https://unpkg.com/react@15.3.2/dist/react.js",
+    "http://builds.emberjs.com/tags/v2.11.0/ember.prod.js",
+    "https://cdn.jsdelivr.net/lodash/4.17.4/lodash.js",
+    "https://cdnjs.cloudflare.com/ajax/libs/d3/4.5.0/d3.js",
+];
+var results = {};
+var remaining = 2 * urls.length;
+function done() {
+    if (!--remaining) {
+        var failures = [];
+        urls.forEach(function(url) {
+            var info = results[url];
+            console.log();
+            console.log(url);
+            console.log(info.log);
+            var elapsed = 0;
+            info.log.replace(/: ([0-9]+\.[0-9]{3})s/g, function(match, time) {
+                elapsed += parseFloat(time);
+            });
+            console.log("Run-time:", elapsed.toFixed(3), "s");
+            console.log("Original:", info.input, "bytes");
+            console.log("Uglified:", info.output, "bytes");
+            console.log("SHA1 sum:", info.sha1);
+            if (info.code) {
+                failures.push(url);
+            }
+        });
+        if (failures.length) {
+            console.error("Benchmark failed:");
+            failures.forEach(function(url) {
+                console.error(url);
+            });
+            process.exit(1);
+        }
+    }
+}
+urls.forEach(function(url) {
+    results[url] = {
+        input: 0,
+        output: 0,
+        log: ""
+    };
+    require(url.slice(0, url.indexOf(":"))).get(url, function(res) {
+        var uglifyjs = fork("bin/uglifyjs", args, { silent: true });
+        res.on("data", function(data) {
+            results[url].input += data.length;
+        }).pipe(uglifyjs.stdin);
+        uglifyjs.stdout.on("data", function(data) {
+            results[url].output += data.length;
+        }).pipe(createHash("sha1")).on("data", function(data) {
+            results[url].sha1 = data.toString("hex");
+            done();
+        });
+        uglifyjs.stderr.setEncoding("utf8");
+        uglifyjs.stderr.on("data", function(data) {
+            results[url].log += data;
+        });
+        uglifyjs.on("exit", function(code) {
+            results[url].code = code;
+            done();
+        });
+    });
+});

test/compress/angular-inject.js

@@ -0,0 +1,67 @@
+ng_inject_defun: {
+    options = {
+        angular: true
+    };
+    input: {
+        /*@ngInject*/
+        function Controller(dependency) {
+            return dependency;
+        }
+    }
+    expect: {
+        function Controller(dependency) {
+            return dependency;
+        }
+        Controller.$inject=['dependency']
+    }
+}
+
+ng_inject_assignment: {
+    options = {
+        angular: true
+    };
+    input: {
+        /*@ngInject*/
+        var Controller = function(dependency) {
+            return dependency;
+        }
+    }
+    expect: {
+        var Controller = function(dependency) {
+            return dependency;
+        }
+        Controller.$inject=['dependency']
+    }
+}
+
+ng_inject_inline: {
+    options = {
+        angular: true
+    };
+    input: {
+        angular.module('a').
+            factory('b',
+                /*@ngInject*/
+                function(dependency) {
+                    return dependency;
+                }).
+            directive('c',
+                /*@ngInject*/
+                function(anotherDependency) {
+                    return anotherDependency;
+                })
+    }
+    expect: {
+        angular.module('a').
+            factory('b',[
+                'dependency',
+                function(dependency) {
+                    return dependency;
+                }]).
+            directive('c',[
+                'anotherDependency',
+                function(anotherDependency) {
+                    return anotherDependency;
+                }])
+    }
+}

test/compress/arrays.js

@@ -1,12 +1,252 @@
+// NOTE trailing comma doesn't contribute to length of an array
+// That also means the array changes length if previous element is a hole too and got cut off
 holes_and_undefined: {
     input: {
+        w = [1,,];
         x = [1, 2, undefined];
         y = [1, , 2, ];
         z = [1, undefined, 3];
     }
     expect: {
+        w=[1,,];
         x=[1,2,void 0];
         y=[1,,2];
         z=[1,void 0,3];
     }
 }
+
+constant_join: {
+    options = {
+        unsafe   : true,
+        evaluate : true
+    };
+    input: {
+        var a = [ "foo", "bar", "baz" ].join("");
+        var a1 = [ "foo", "bar", "baz" ].join();
+        var a2 = [ "foo", "bar", "baz" ].join(null);
+        var a3 = [ "foo", "bar", "baz" ].join(void 0);
+        var a4 = [ "foo", , "baz" ].join();
+        var a5 = [ "foo", null, "baz" ].join();
+        var a6 = [ "foo", void 0, "baz" ].join();
+        var b = [ "foo", 1, 2, 3, "bar" ].join("");
+        var c = [ boo(), "foo", 1, 2, 3, "bar", bar() ].join("");
+        var c1 = [ boo(), bar(), "foo", 1, 2, 3, "bar", bar() ].join("");
+        var c2 = [ 1, 2, "foo", "bar", baz() ].join("");
+        var c3 = [ boo() + bar() + "foo", 1, 2, 3, "bar", bar() + "foo" ].join("");
+        var c4 = [ 1, 2, null, undefined, "foo", "bar", baz() ].join("");
+        var c5 = [ boo() + bar() + "foo", 1, 2, 3, "bar", bar() + "foo" ].join();
+        var c6 = [ 1, 2, null, undefined, "foo", "bar", baz() ].join();
+        var d = [ "foo", 1 + 2 + "bar", "baz" ].join("-");
+        var e = [].join(foo + bar);
+        var f = [].join("");
+        var g = [].join("foo");
+    }
+    expect: {
+        var a = "foobarbaz";
+        var a1 = "foo,bar,baz";
+        var a2 = "foonullbarnullbaz";
+        var a3 = "foo,bar,baz";
+        var a4 = "foo,,baz";
+        var a5 = "foo,,baz";
+        var a6 = "foo,,baz";
+        var b = "foo123bar";
+        var c = boo() + "foo123bar" + bar();
+        var c1 = "" + boo() + bar() + "foo123bar" + bar();
+        var c2 = "12foobar" + baz();
+        var c3 = boo() + bar() + "foo123bar" + bar() + "foo";
+        var c4 = "12foobar" + baz();
+        var c5 = [ boo() + bar() + "foo", 1, 2, 3, "bar", bar() + "foo" ].join();
+        var c6 = [ "1,2,,,foo,bar", baz() ].join();
+        var d = "foo-3bar-baz";
+        var e = [].join(foo + bar);
+        var f = "";
+        var g = "";
+    }
+}
+
+constant_join_2: {
+    options = {
+        unsafe   : true,
+        evaluate : true
+    };
+    input: {
+        var a = [ "foo", "bar", boo(), "baz", "x", "y" ].join("");
+        var b = [ "foo", "bar", boo(), "baz", "x", "y" ].join("-");
+        var c = [ "foo", "bar", boo(), "baz", "x", "y" ].join("really-long-separator");
+        var d = [ "foo", "bar", boo(),
+                  [ "foo", 1, 2, 3, "bar" ].join("+"),
+                  "baz", "x", "y" ].join("-");
+        var e = [ "foo", "bar", boo(),
+                  [ "foo", 1, 2, 3, "bar" ].join("+"),
+                  "baz", "x", "y" ].join("really-long-separator");
+        var f = [ "str", "str" + variable, "foo", "bar", "moo" + foo ].join("");
+    }
+    expect: {
+        var a = "foobar" + boo() + "bazxy";
+        var b = [ "foo-bar", boo(), "baz-x-y" ].join("-");
+        var c = [ "foo", "bar", boo(), "baz", "x", "y" ].join("really-long-separator");
+        var d = [ "foo-bar", boo(), "foo+1+2+3+bar-baz-x-y" ].join("-");
+        var e = [ "foo", "bar", boo(),
+                  "foo+1+2+3+bar",
+                  "baz", "x", "y" ].join("really-long-separator");
+        var f = "strstr" + variable + "foobarmoo" + foo;
+    }
+}
+
+spread_with_variable_as_last_element: {
+    input: {
+        var values = [4, 5, 6];
+        var a = [1, 2, 3, ...values];
+    }
+    expect: {
+        var values = [4, 5, 6];
+        var a = [1, 2, 3, ...values];
+    }
+}
+
+spread_with_variable_in_middle: {
+    input: {
+        var values = [4, 5, 6];
+        var a = [1, 2, 3, ...values, 7,,,];
+    }
+    expect: {
+        var values = [4, 5, 6];
+        var a = [1, 2, 3, ...values, 7,,,];
+    }
+}
+
+spread_with_variable_at_front: {
+    input: {
+        var values = [1, 2, 3];
+        var a = [...values, 4, 5, 6];
+    }
+    expect: {
+        var values = [1, 2, 3];
+        var a = [...values, 4, 5, 6];
+    }
+}
+
+spread_with_variable_at_front_after_elisions: {
+    input: {
+        var values = [1, 2, 3];
+        var a = [,,,...values, 4, 5, 6];
+    }
+    expect: {
+        var values = [1, 2, 3];
+        var a = [,,,...values, 4, 5, 6];
+    }
+}
+
+spread_with_array_at_end: {
+    input: {
+        var a = [1, 2, ...[4, 5, 6]];
+    }
+    expect: {
+        var a = [1, 2, ...[4, 5, 6]];
+    }
+}
+
+spread_with_logical_expression_at_end: {
+    options = { evaluate: true }
+    input: {
+        var a = [1, 2, 3, ...[2+2]]
+    }
+    expect: {
+        var a = [1, 2, 3, ...[4]]
+    }
+}
+
+spread_with_logical_expression_at_middle: {
+    options = { evaluate: true }
+    input: {
+        var a = [1, 1, ...[1+1, 1+2, 2+3], 8]
+    }
+    expect: {
+        var a = [1, 1, ...[2, 3, 5], 8]
+    }
+}
+
+constant_join_3: {
+    options = {
+        unsafe: true,
+        evaluate: true,
+    };
+    input: {
+        var a = [ null ].join();
+        var b = [ , ].join();
+        var c = [ , 1, , 3 ].join();
+        var d = [ foo ].join();
+        var e = [ foo, null, undefined, bar ].join("-");
+        var f = [ foo, bar ].join("");
+        var g = [ null, "foo", null, bar + "baz" ].join("");
+        var h = [ null, "foo", null, bar + "baz" ].join("-");
+        var i = [ "foo" + bar, null, baz + "moo" ].join("");
+        var j = [ foo + "bar", baz ].join("");
+        var k = [ foo, "bar" + baz ].join("");
+        var l = [ foo, bar + "baz" ].join("");
+    }
+    expect: {
+        var a = "";
+        var b = "";
+        var c = ",1,,3";
+        var d = "" + foo;
+        var e = [ foo, "-", bar ].join("-");
+        var f = "" + foo + bar;
+        var g = "foo" + bar + "baz";
+        var h = [ "-foo-", bar + "baz" ].join("-");
+        var i = "foo" + bar + baz + "moo";
+        var j = foo + "bar" + baz;
+        var k = foo + "bar" + baz;
+        var l = foo + (bar + "baz");
+    }
+}
+
+for_loop: {
+    options = {
+        unsafe      : true,
+        unused      : true,
+        evaluate    : true,
+        reduce_vars : true
+    };
+    input: {
+        function f0() {
+            var a = [1, 2, 3];
+            for (var i = 0; i < a.length; i++) {
+                console.log(a[i]);
+            }
+        }
+
+        function f1() {
+            var a = [1, 2, 3];
+            for (var i = 0, len = a.length; i < len; i++) {
+                console.log(a[i]);
+            }
+        }
+
+        function f2() {
+            var a = [1, 2, 3];
+            for (var i = 0; i < a.length; i++) {
+                a[i]++;
+            }
+        }
+    }
+    expect: {
+        function f0() {
+            var a = [1, 2, 3];
+            for (var i = 0; i < 3; i++)
+                console.log(a[i]);
+        }
+
+        function f1() {
+            var a = [1, 2, 3];
+            for (var i = 0; i < 3; i++)
+                console.log(a[i]);
+        }
+
+        function f2() {
+            var a = [1, 2, 3];
+            for (var i = 0; i < a.length; i++)
+                a[i]++;
+        }
+    }
+}

test/compress/arrow.js

@@ -0,0 +1,137 @@
+arrow_functions_without_body: {
+    input: {
+        var a1 = () => 42;
+        var a2 = (p) => p;
+        var a3 = p => p;
+        var a4 = (...p) => p;
+        var a5 = (b, c) => b + c;
+        var a6 = (b, ...c) => b + c[0];
+        var a7 = (...b) => b.join();
+    }
+    expect: {
+        var a1 = () => 42;
+        var a2 = (p) => p;
+        var a3 = p => p;
+        var a4 = (...p) => p;
+        var a5 = (b, c) => b + c;
+        var a6 = (b, ...c) => b + c[0];
+        var a7 = (...b) => b.join();
+    }
+}
+
+arrow_functions_with_body: {
+    input: {
+        var a1 = () => {
+            var a = 42 * Math.random();
+            return a;
+        };
+        var a2 = (p) => {
+            var a = Math.random() * p;
+            return a;
+        };
+        var a3 = p => {
+            var a = Math.random() * p;
+            return a;
+        };
+        var a4 = (...p) => {
+            var a = Math.random() * p;
+            return a;
+        };
+        var a5 = (b, c) => {
+            var result = b * c + b / c;
+            return result
+        };
+        var a6 = (b, ...c) => {
+            var result = b;
+            for (var i = 0; i < c.length; i++)
+                result += c[i];
+            return result
+        };
+        var a7 = (...b) => {
+            b.join();
+        }
+    }
+    expect: {
+        var a1 = () => {
+            var a = 42 * Math.random();
+            return a;
+        };
+        var a2 = (p) => {
+            var a = Math.random() * p;
+            return a;
+        };
+        var a3 = p => {
+            var a = Math.random() * p;
+            return a;
+        };
+        var a4 = (...p) => {
+            var a = Math.random() * p;
+            return a;
+        };
+        var a5 = (b, c) => {
+            var result = b * c + b / c;
+            return result
+        };
+        var a6 = (b, ...c) => {
+            var result = b;
+            for (var i = 0; i < c.length; i++)
+                result += c[i];
+            return result
+        };
+        var a7 = (...b) => {
+            b.join();
+        };
+    }
+}
+
+arrow_function_with_single_parameter_with_default: {
+    input: {
+        var foo = (a = 0) => doSomething(a);
+    }
+    expect_exact: "var foo=(a=0)=>doSomething(a);"
+}
+
+arrow_binding_pattern: {
+    input: {
+        var foo = ([]) => "foo";
+        var bar = ({}) => "bar";
+        var with_default = (foo = "default") => foo;
+        var object_with_default = ({foo = "default", bar: baz = "default"}) => foo;
+        var array_after_spread = (...[foo]) => foo;
+        var array_after_spread = (...{foo}) => foo;
+        var computed = ({ [compute()]: x }) => {};
+        var array_hole = ([, , ...x] = [1, 2]) => {};
+        var object_trailing_elision = ({foo,}) => {};
+        var spread_empty_array = (...[]) => "foo";
+        var spread_empty_object = (...{}) => "foo";
+    }
+    expect: {
+        var foo = ([]) => "foo";
+        var bar = ({}) => "bar";
+        var with_default = (foo = "default") => foo;
+        var object_with_default = ({foo = "default", bar: baz = "default"}) => foo;
+        var array_after_spread = (...[foo]) => foo;
+        var array_after_spread = (...{foo}) => foo;
+        var computed = ({ [compute()]: x }) => {};
+        var array_hole = ([, , ...x] = [1, 2]) => {};
+        var object_trailing_elision = ({foo,}) => {};
+        var spread_empty_array = (...[]) => "foo";
+        var spread_empty_object = (...{}) => "foo";
+    }
+}
+
+arrow_binding_pattern_strict: {
+    input: {
+        var foo = ([,]) => "foo";
+    }
+    expect_exact: 'var foo=([,])=>"foo";'
+}
+
+arrow_with_regexp: {
+    input: {
+        num => /\d{11,14}/.test( num )
+    }
+    expect: {
+        num => /\d{11,14}/.test( num )
+    }
+}

test/compress/ascii.js

@@ -0,0 +1,36 @@
+ascii_only_true: {
+    options = {}
+    beautify = {
+        ascii_only : true,
+        screw_ie8  : true,
+        beautify   : false,
+    }
+    input: {
+        function f() {
+            return "\x000\x001\x007\x008\x00" +
+                   "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f" +
+                   "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" +
+                   "\x20\x21\x22\x23 ... \x7d\x7e\x7f\x80\x81 ... \xfe\xff\u0fff\uffff";
+        }
+    }
+    expect_exact: 'function f(){return"\\x000\\x001\\x007\\08\\0"+"\\0\\x01\\x02\\x03\\x04\\x05\\x06\\x07\\b\\t\\n\\v\\f\\r\\x0e\\x0f"+"\\x10\\x11\\x12\\x13\\x14\\x15\\x16\\x17\\x18\\x19\\x1a\\x1b\\x1c\\x1d\\x1e\\x1f"+\' !"# ... }~\\x7f\\x80\\x81 ... \\xfe\\xff\\u0fff\\uffff\'}'
+}
+
+ascii_only_false: {
+    options = {}
+    beautify = {
+        ascii_only : false,
+        screw_ie8  : true,
+        beautify   : false,
+    }
+    input: {
+        function f() {
+            return "\x000\x001\x007\x008\x00" +
+                   "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f" +
+                   "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" +
+                   "\x20\x21\x22\x23 ... \x7d\x7e\x7f\x80\x81 ... \xfe\xff\u0fff\uffff";
+        }
+    }
+    expect_exact: 'function f(){return"\\x000\\x001\\x007\\08\\0"+"\\0\x01\x02\x03\x04\x05\x06\x07\\b\\t\\n\\v\\f\\r\x0e\x0f"+"\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f"+\' !"# ... }~\x7f\x80\x81 ... \xfe\xff\u0fff\uffff\'}'
+}
+

test/compress/asm.js

@@ -0,0 +1,106 @@
+asm_mixed: {
+    options = {
+        sequences     : true,
+        properties    : true,
+        dead_code     : true,
+        drop_debugger : true,
+        conditionals  : true,
+        comparisons   : true,
+        evaluate      : true,
+        booleans      : true,
+        loops         : true,
+        unused        : true,
+        hoist_funs    : true,
+        keep_fargs    : true,
+        keep_fnames   : false,
+        hoist_vars    : true,
+        if_return     : true,
+        join_vars     : true,
+        cascade       : true,
+        side_effects  : true,
+        negate_iife   : true
+    };
+    input: {
+        // adapted from http://asmjs.org/spec/latest/
+        function asm_GeometricMean(stdlib, foreign, buffer) {
+          "use asm";
+          var exp = stdlib.Math.exp;
+          var log = stdlib.Math.log;
+          var values = new stdlib.Float64Array(buffer);
+          function logSum(start, end) {
+            start = start|0;
+            end = end|0;
+            var sum = 0.0, p = 0, q = 0;
+            // asm.js forces byte addressing of the heap by requiring shifting by 3
+            for (p = start << 3, q = end << 3; (p|0) < (q|0); p = (p + 8)|0) {
+              sum = sum + +log(values[p>>3]);
+            }
+            return +sum;
+          }
+          function geometricMean(start, end) {
+            start = start|0;
+            end = end|0;
+            return +exp(+logSum(start, end) / +((end - start)|0));
+          }
+          return { geometricMean: geometricMean };
+        }
+        function no_asm_GeometricMean(stdlib, foreign, buffer) {
+          var exp = stdlib.Math.exp;
+          var log = stdlib.Math.log;
+          var values = new stdlib.Float64Array(buffer);
+          function logSum(start, end) {
+            start = start|0;
+            end = end|0;
+            var sum = 0.0, p = 0, q = 0;
+            // asm.js forces byte addressing of the heap by requiring shifting by 3
+            for (p = start << 3, q = end << 3; (p|0) < (q|0); p = (p + 8)|0) {
+              sum = sum + +log(values[p>>3]);
+            }
+            return +sum;
+          }
+          function geometricMean(start, end) {
+            start = start|0;
+            end = end|0;
+            return +exp(+logSum(start, end) / +((end - start)|0));
+          }
+          return { geometricMean: geometricMean };
+        }
+    }
+    expect: {
+        function asm_GeometricMean(stdlib, foreign, buffer) {
+            "use asm";
+            var exp = stdlib.Math.exp;
+            var log = stdlib.Math.log;
+            var values = new stdlib.Float64Array(buffer);
+            function logSum(start, end) {
+                start = start | 0;
+                end = end | 0;
+                var sum = 0.0, p = 0, q = 0;
+                for (p = start << 3, q = end << 3; (p | 0) < (q | 0); p = p + 8 | 0) {
+                    sum = sum + +log(values[p >> 3]);
+                }
+                return +sum;
+            }
+            function geometricMean(start, end) {
+                start = start | 0;
+                end = end | 0;
+                return +exp(+logSum(start, end) / +(end - start | 0));
+            }
+            return { geometricMean: geometricMean };
+        }
+        function no_asm_GeometricMean(stdlib, foreign, buffer) {
+            function logSum(start, end) {
+                start |= 0, end |= 0;
+                var sum = 0, p = 0, q = 0;
+                for (p = start << 3, q = end << 3; (0 | p) < (0 | q); p = p + 8 | 0) sum += +log(values[p >> 3]);
+                return +sum;
+            }
+            function geometricMean(start, end) {
+                return start |= 0, end |= 0, +exp(+logSum(start, end) / +(end - start | 0));
+            }
+            var exp = stdlib.Math.exp, log = stdlib.Math.log, values = new stdlib.Float64Array(buffer);
+            return { geometricMean: geometricMean };
+        }
+    }
+}
+

test/compress/assignment.js

@@ -0,0 +1,238 @@
+op_equals_left_local_var: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        var x;
+
+        x = x +   3;
+        x = x -   3;
+        x = x /   3;
+        x = x *   3;
+        x = x >>  3;
+        x = x <<  3;
+        x = x >>> 3;
+        x = x |   3;
+        x = x ^   3;
+        x = x %   3;
+        x = x &   3;
+
+        x = x +   g();
+        x = x -   g();
+        x = x /   g();
+        x = x *   g();
+        x = x >>  g();
+        x = x <<  g();
+        x = x >>> g();
+        x = x |   g();
+        x = x ^   g();
+        x = x %   g();
+        x = x &   g();
+    }
+    expect: {
+        var x;
+
+        x   += 3;
+        x   -= 3;
+        x   /= 3;
+        x   *= 3;
+        x  >>= 3;
+        x  <<= 3;
+        x >>>= 3;
+        x   |= 3;
+        x   ^= 3;
+        x   %= 3;
+        x   &= 3;
+
+        x   += g();
+        x   -= g();
+        x   /= g();
+        x   *= g();
+        x  >>= g();
+        x  <<= g();
+        x >>>= g();
+        x   |= g();
+        x   ^= g();
+        x   %= g();
+        x   &= g();
+    }
+}
+
+op_equals_right_local_var: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        var x;
+
+        x = (x -= 2) ^ x;
+
+        x = 3 +   x;
+        x = 3 -   x;
+        x = 3 /   x;
+        x = 3 *   x;
+        x = 3 >>  x;
+        x = 3 <<  x;
+        x = 3 >>> x;
+        x = 3 |   x;
+        x = 3 ^   x;
+        x = 3 %   x;
+        x = 3 &   x;
+
+        x = g() +   x;
+        x = g() -   x;
+        x = g() /   x;
+        x = g() *   x;
+        x = g() >>  x;
+        x = g() <<  x;
+        x = g() >>> x;
+        x = g() |   x;
+        x = g() ^   x;
+        x = g() %   x;
+        x = g() &   x;
+    }
+    expect: {
+        var x;
+
+        x = (x -= 2) ^ x;
+
+        x = 3 + x;
+        x = 3 - x;
+        x = 3 / x;
+        x *= 3;
+        x = 3 >> x;
+        x = 3 << x;
+        x = 3 >>> x;
+        x |= 3;
+        x ^= 3;
+        x = 3 % x;
+        x &= 3;
+
+        x = g() +   x;
+        x = g() -   x;
+        x = g() /   x;
+        x = g() *   x;
+        x = g() >>  x;
+        x = g() <<  x;
+        x = g() >>> x;
+        x = g() |   x;
+        x = g() ^   x;
+        x = g() %   x;
+        x = g() &   x;
+    }
+}
+op_equals_left_global_var: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        x = x +   3;
+        x = x -   3;
+        x = x /   3;
+        x = x *   3;
+        x = x >>  3;
+        x = x <<  3;
+        x = x >>> 3;
+        x = x |   3;
+        x = x ^   3;
+        x = x %   3;
+        x = x &   3;
+
+        x = x +   g();
+        x = x -   g();
+        x = x /   g();
+        x = x *   g();
+        x = x >>  g();
+        x = x <<  g();
+        x = x >>> g();
+        x = x |   g();
+        x = x ^   g();
+        x = x %   g();
+        x = x &   g();
+    }
+    expect: {
+        x   += 3;
+        x   -= 3;
+        x   /= 3;
+        x   *= 3;
+        x  >>= 3;
+        x  <<= 3;
+        x >>>= 3;
+        x   |= 3;
+        x   ^= 3;
+        x   %= 3;
+        x   &= 3;
+
+        x   += g();
+        x   -= g();
+        x   /= g();
+        x   *= g();
+        x  >>= g();
+        x  <<= g();
+        x >>>= g();
+        x   |= g();
+        x   ^= g();
+        x   %= g();
+        x   &= g();
+    }
+}
+
+op_equals_right_global_var: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        x = (x -= 2) ^ x;
+
+        x = 3 +   x;
+        x = 3 -   x;
+        x = 3 /   x;
+        x = 3 *   x;
+        x = 3 >>  x;
+        x = 3 <<  x;
+        x = 3 >>> x;
+        x = 3 |   x;
+        x = 3 ^   x;
+        x = 3 %   x;
+        x = 3 &   x;
+
+        x = g() +   x;
+        x = g() -   x;
+        x = g() /   x;
+        x = g() *   x;
+        x = g() >>  x;
+        x = g() <<  x;
+        x = g() >>> x;
+        x = g() |   x;
+        x = g() ^   x;
+        x = g() %   x;
+        x = g() &   x;
+    }
+    expect: {
+        x = (x -= 2) ^ x;
+
+        x = 3 +   x;
+        x = 3 -   x;
+        x = 3 /   x;
+        x *= 3;
+        x = 3 >>  x;
+        x = 3 <<  x;
+        x = 3 >>> x;
+        x |= 3;
+        x ^= 3;
+        x = 3 %   x;
+        x &= 3;
+
+        x = g() +   x;
+        x = g() -   x;
+        x = g() /   x;
+        x = g() *   x;
+        x = g() >>  x;
+        x = g() <<  x;
+        x = g() >>> x;
+        x = g() |   x;
+        x = g() ^   x;
+        x = g() %   x;
+        x = g() &   x;
+    }
+}

test/compress/block-scope.js

@@ -0,0 +1,177 @@
+
+let_statement: {
+    input: {
+        let x = 6;
+    }
+    expect_exact: "let x=6;"
+}
+
+do_not_hoist_let: {
+    options = {
+        hoist_vars: true,
+    };
+    input: {
+        function x() {
+            if (FOO) {
+                let let1;
+                let let2;
+                var var1;
+                var var2;
+            }
+        }
+    }
+    expect: {
+        function x() {
+            var var1, var2;
+            if (FOO) {
+                let let1;
+                let let2;
+            }
+        }
+    }
+}
+
+do_not_remove_anon_blocks_if_they_have_decls: {
+    input: {
+        function x() {
+            {
+                let x;
+            }
+            {
+                var x;
+            }
+            {
+                const y;
+                class Zee {};
+            }
+        }
+        {
+            let y;
+        }
+        {
+            var y;
+        }
+    }
+    expect: {
+        function x(){
+            {
+                let x
+            }
+            var x;
+            {
+                const y;
+                class Zee {}
+            }
+        }
+        {
+            let y
+        }
+        var y;
+    }
+}
+
+remove_unused_in_global_block: {
+    options = {
+        unused: true,
+    }
+    input: {
+        {
+            let x;
+            const y;
+            class Zee {};
+            var w;
+        }
+        let ex;
+        const why;
+        class Zed {};
+        var wut;
+        console.log(x, y, Zee);
+    }
+    expect: {
+        var w;
+        let ex;
+        const why;
+        class Zed {};
+        var wut;
+        console.log(x, y, Zee);
+    }
+}
+
+regression_block_scope_resolves: {
+    mangle = { };
+    options = {
+        dead_code: false
+    };
+    input: {
+        (function () {
+            if(1) {
+                let x;
+                const y;
+                class Zee {};
+            }
+            if(1) {
+                let ex;
+                const why;
+                class Zi {};
+            }
+            console.log(x, y, Zee, ex, why, Zi);
+        }());
+    }
+    expect: {
+        (function () {
+            if (1) {
+                let o;
+                const n;
+                class c {};
+            }
+            if (1) {
+                let o;
+                const n;
+                class c {};
+            }
+            console.log(x, y, Zee, ex, why, Zi);
+        }());
+    }
+}
+
+switch_block_scope_mangler: {
+    mangle = {}
+    input: {
+        var fn = function(code) {
+            switch (code) {
+                case 1:
+                    let apple = code + 1;
+                    let dog = code + 4;
+                    console.log(apple, dog);
+                    break;
+                case 2:
+                    let banana = code + 2;
+                    console.log(banana);
+                    break;
+                default:
+                    let cat = code + 3;
+                    console.log(cat);
+            }
+        };
+    }
+    expect: {
+        var fn = function(o) {
+            switch (o) {
+              case 1:
+                let e = o + 1
+                let c = o + 4;
+                console.log(e, c);
+                break;
+
+              case 2:
+                let l = o + 2;
+                console.log(l);
+                break;
+
+              default:
+                let a = o + 3;
+                console.log(a);
+            }
+        };
+    }
+}

test/compress/comparing.js

@@ -0,0 +1,76 @@
+keep_comparisons: {
+    options = {
+        comparisons: true,
+        unsafe_comps: false
+    }
+    input: {
+        var obj1 = {
+            valueOf: function() {triggeredFirst();}
+        }
+        var obj2 = {
+            valueOf: function() {triggeredSecond();}
+        }
+        var result1 = obj1 <= obj2;
+        var result2 = obj1 <  obj2;
+        var result3 = obj1 >= obj2;
+        var result4 = obj1 >  obj2;
+    }
+    expect: {
+        var obj1 = {
+            valueOf: function() {triggeredFirst();}
+        }
+        var obj2 = {
+            valueOf: function() {triggeredSecond();}
+        }
+        var result1 = obj1 <= obj2;
+        var result2 = obj1 <  obj2;
+        var result3 = obj1 >= obj2;
+        var result4 = obj1 >  obj2;
+    }
+}
+
+keep_comparisons_with_unsafe_comps: {
+    options = {
+        comparisons: true,
+        unsafe_comps: true
+    }
+    input: {
+        var obj1 = {
+            valueOf: function() {triggeredFirst();}
+        }
+        var obj2 = {
+            valueOf: function() {triggeredSecond();}
+        }
+        var result1 = obj1 <= obj2;
+        var result2 = obj1 <  obj2;
+        var result3 = obj1 >= obj2;
+        var result4 = obj1 >  obj2;
+    }
+    expect: {
+        var obj1 = {
+            valueOf: function() {triggeredFirst();}
+        }
+        var obj2 = {
+            valueOf: function() {triggeredSecond();}
+        }
+        var result1 = obj2 >= obj1;
+        var result2 = obj2 >  obj1;
+        var result3 = obj1 >= obj2;
+        var result4 = obj1 >  obj2;
+    }
+}
+
+dont_change_in_or_instanceof_expressions: {
+    input: {
+        1 in 1;
+        null in null;
+        1 instanceof 1;
+        null instanceof null;
+    }
+    expect: {
+        1 in 1;
+        null in null;
+        1 instanceof 1;
+        null instanceof null;
+    }
+}

test/compress/concat-strings.js

@@ -0,0 +1,223 @@
+concat_1: {
+    options = {
+        evaluate: true
+    };
+    input: {
+        var a = "foo" + "bar" + x() + "moo" + "foo" + y() + "x" + "y" + "z" + q();
+        var b = "foo" + 1 + x() + 2 + "boo";
+        var c = 1 + x() + 2 + "boo";
+
+        // this CAN'T safely be shortened to 1 + x() + "5boo"
+        var d = 1 + x() + 2 + 3 + "boo";
+
+        var e = 1 + x() + 2 + "X" + 3 + "boo";
+
+        // be careful with concatentation with "\0" with octal-looking strings.
+        var f = "\0" + 360 + "\0" + 8 + "\0";
+    }
+    expect: {
+        var a = "foobar" + x() + "moofoo" + y() + "xyz" + q();
+        var b = "foo1" + x() + "2boo";
+        var c = 1 + x() + 2 + "boo";
+        var d = 1 + x() + 2 + 3 + "boo";
+        var e = 1 + x() + 2 + "X3boo";
+        var f = "\x00360\08\0";
+    }
+}
+
+concat_2: {
+    options = {};
+    input: {
+        console.log(
+            1 + (2 + 3),
+            1 + (2 + "3"),
+            1 + ("2" + 3),
+            1 + ("2" + "3"),
+            "1" + (2 + 3),
+            "1" + (2 + "3"),
+            "1" + ("2" + 3),
+            "1" + ("2" + "3")
+        );
+    }
+    expect: {
+        console.log(
+            1 + (2 + 3),
+            1 + (2 + "3"),
+            1 + "2" + 3,
+            1 + "2" + "3",
+            "1" + (2 + 3),
+            "1" + 2 + "3",
+            "1" + "2" + 3,
+            "1" + "2" + "3"
+        );
+    }
+    expect_stdout: true
+}
+
+concat_3: {
+    options = {};
+    input: {
+        console.log(
+            1 + 2 + (3 + 4 + 5),
+            1 + 2 + (3 + 4 + "5"),
+            1 + 2 + (3 + "4" + 5),
+            1 + 2 + (3 + "4" + "5"),
+            1 + 2 + ("3" + 4 + 5),
+            1 + 2 + ("3" + 4 + "5"),
+            1 + 2 + ("3" + "4" + 5),
+            1 + 2 + ("3" + "4" + "5")
+        );
+    }
+    expect: {
+        console.log(
+            1 + 2 + (3 + 4 + 5),
+            1 + 2 + (3 + 4 + "5"),
+            1 + 2 + (3 + "4") + 5,
+            1 + 2 + (3 + "4") + "5",
+            1 + 2 + "3" + 4 + 5,
+            1 + 2 + "3" + 4 + "5",
+            1 + 2 + "3" + "4" + 5,
+            1 + 2 + "3" + "4" + "5"
+        );
+    }
+    expect_stdout: true
+}
+
+concat_4: {
+    options = {};
+    input: {
+        console.log(
+            1 + "2" + (3 + 4 + 5),
+            1 + "2" + (3 + 4 + "5"),
+            1 + "2" + (3 + "4" + 5),
+            1 + "2" + (3 + "4" + "5"),
+            1 + "2" + ("3" + 4 + 5),
+            1 + "2" + ("3" + 4 + "5"),
+            1 + "2" + ("3" + "4" + 5),
+            1 + "2" + ("3" + "4" + "5")
+        );
+    }
+    expect: {
+        console.log(
+            1 + "2" + (3 + 4 + 5),
+            1 + "2" + (3 + 4) + "5",
+            1 + "2" + 3 + "4" + 5,
+            1 + "2" + 3 + "4" + "5",
+            1 + "2" + "3" + 4 + 5,
+            1 + "2" + "3" + 4 + "5",
+            1 + "2" + "3" + "4" + 5,
+            1 + "2" + "3" + "4" + "5"
+        );
+    }
+    expect_stdout: true
+}
+
+concat_5: {
+    options = {};
+    input: {
+        console.log(
+            "1" + 2 + (3 + 4 + 5),
+            "1" + 2 + (3 + 4 + "5"),
+            "1" + 2 + (3 + "4" + 5),
+            "1" + 2 + (3 + "4" + "5"),
+            "1" + 2 + ("3" + 4 + 5),
+            "1" + 2 + ("3" + 4 + "5"),
+            "1" + 2 + ("3" + "4" + 5),
+            "1" + 2 + ("3" + "4" + "5")
+        );
+    }
+    expect: {
+        console.log(
+            "1" + 2 + (3 + 4 + 5),
+            "1" + 2 + (3 + 4) + "5",
+            "1" + 2 + 3 + "4" + 5,
+            "1" + 2 + 3 + "4" + "5",
+            "1" + 2 + "3" + 4 + 5,
+            "1" + 2 + "3" + 4 + "5",
+            "1" + 2 + "3" + "4" + 5,
+            "1" + 2 + "3" + "4" + "5"
+        );
+    }
+    expect_stdout: true
+}
+
+concat_6: {
+    options = {};
+    input: {
+        console.log(
+            "1" + "2" + (3 + 4 + 5),
+            "1" + "2" + (3 + 4 + "5"),
+            "1" + "2" + (3 + "4" + 5),
+            "1" + "2" + (3 + "4" + "5"),
+            "1" + "2" + ("3" + 4 + 5),
+            "1" + "2" + ("3" + 4 + "5"),
+            "1" + "2" + ("3" + "4" + 5),
+            "1" + "2" + ("3" + "4" + "5")
+        );
+    }
+    expect: {
+        console.log(
+            "1" + "2" + (3 + 4 + 5),
+            "1" + "2" + (3 + 4) + "5",
+            "1" + "2" + 3 + "4" + 5,
+            "1" + "2" + 3 + "4" + "5",
+            "1" + "2" + "3" + 4 + 5,
+            "1" + "2" + "3" + 4 + "5",
+            "1" + "2" + "3" + "4" + 5,
+            "1" + "2" + "3" + "4" + "5"
+        );
+    }
+    expect_stdout: true
+}
+
+concat_7: {
+    input: {
+        console.log(
+            "" + 1,
+            "" + "1",
+            "" + 1 + 2,
+            "" + 1 + "2",
+            "" + "1" + 2,
+            "" + "1" + "2",
+            "" + (x += "foo")
+        );
+    }
+    expect: {
+        console.log(
+            "" + 1,
+            "1",
+            "" + 1 + 2,
+            1 + "2",
+            "1" + 2,
+            "1" + "2",
+            x += "foo"
+        );
+    }
+    expect_stdout: true
+}
+
+concat_8: {
+    input: {
+        console.log(
+            1 + "",
+            "1" + "",
+            1 + 2 + "",
+            1 + "2" + "",
+            "1" + 2 + "",
+            "1" + "2" + "",
+            (x += "foo") + ""
+        );
+    }
+    expect: {
+        console.log(
+            1 + "",
+            "1",
+            1 + 2 + "",
+            1 + "2",
+            "1" + 2,
+            "1" + "2",
+            x += "foo"
+        );
+    }
+    expect_stdout: true
+}

test/compress/conditionals.js

@@ -50,9 +50,11 @@ ifs_3_should_warn: {
         conditionals : true,
         dead_code    : true,
         evaluate     : true,
-        booleans     : true
+        booleans     : true,
+        side_effects : true,
     };
     input: {
+        var x, y;
         if (x && !(x + "1") && y) { // 1
             var qq;
             foo();
@@ -68,6 +70,7 @@ ifs_3_should_warn: {
         }
     }
     expect: {
+        var x, y;
         var qq; bar();          // 1
         var jj; foo();          // 2
     }
@@ -84,7 +87,9 @@ ifs_4: {
             x(foo)[10].bar.baz = something_else();
     }
     expect: {
-        x(foo)[10].bar.baz = (foo && bar) ? something() : something_else();
+        foo && bar
+            ? x(foo)[10].bar.baz = something()
+            : x(foo)[10].bar.baz = something_else();
     }
 }
 
@@ -131,13 +136,760 @@ ifs_6: {
         comparisons: true
     };
     input: {
+        var x, y;
         if (!foo && !bar && !baz && !boo) {
             x = 10;
         } else {
             x = 20;
         }
+        if (y) {
+            x[foo] = 10;
+        } else {
+            x[foo] = 20;
+        }
+        if (foo) {
+            x[bar] = 10;
+        } else {
+            x[bar] = 20;
+        }
     }
     expect: {
+        var x, y;
         x = foo || bar || baz || boo ? 20 : 10;
+        x[foo] = y ? 10 : 20;
+        foo ? x[bar] = 10 : x[bar] = 20;
     }
 }
+
+cond_1: {
+    options = {
+        conditionals: true
+    };
+    input: {
+        var do_something; // if undeclared it's assumed to have side-effects
+        if (some_condition()) {
+            do_something(x);
+        } else {
+            do_something(y);
+        }
+        if (some_condition()) {
+            side_effects(x);
+        } else {
+            side_effects(y);
+        }
+    }
+    expect: {
+        var do_something;
+        do_something(some_condition() ? x : y);
+        some_condition() ? side_effects(x) : side_effects(y);
+    }
+}
+
+cond_2: {
+    options = {
+        conditionals: true
+    };
+    input: {
+        var x, FooBar;
+        if (some_condition()) {
+            x = new FooBar(1);
+        } else {
+            x = new FooBar(2);
+        }
+    }
+    expect: {
+        var x, FooBar;
+        x = new FooBar(some_condition() ? 1 : 2);
+    }
+}
+
+cond_3: {
+    options = {
+        conditionals: true
+    };
+    input: {
+        var FooBar;
+        if (some_condition()) {
+            new FooBar(1);
+        } else {
+            FooBar(2);
+        }
+    }
+    expect: {
+        var FooBar;
+        some_condition() ? new FooBar(1) : FooBar(2);
+    }
+}
+
+cond_4: {
+    options = {
+        conditionals: true
+    };
+    input: {
+        var do_something;
+        if (some_condition()) {
+            do_something();
+        } else {
+            do_something();
+        }
+        if (some_condition()) {
+            side_effects();
+        } else {
+            side_effects();
+        }
+    }
+    expect: {
+        var do_something;
+        some_condition(), do_something();
+        some_condition(), side_effects();
+    }
+}
+
+cond_5: {
+    options = {
+        conditionals: true
+    };
+    input: {
+        if (some_condition()) {
+            if (some_other_condition()) {
+                do_something();
+            } else {
+                alternate();
+            }
+        } else {
+            alternate();
+        }
+
+        if (some_condition()) {
+            if (some_other_condition()) {
+                do_something();
+            }
+        }
+    }
+    expect: {
+        some_condition() && some_other_condition() ? do_something() : alternate();
+        some_condition() && some_other_condition() && do_something();
+    }
+}
+
+cond_7: {
+    options = {
+        conditionals: true,
+        evaluate    : true,
+        side_effects: true,
+    };
+    input: {
+        var x, y, z, a, b;
+        // compress these
+        if (y) {
+            x = 1+1;
+        } else {
+            x = 2;
+        }
+
+        if (y) {
+            x = 1+1;
+        } else if (z) {
+            x = 2;
+        } else {
+            x = 3-1;
+        }
+
+        x = y ? 'foo' : 'fo'+'o';
+
+        x = y ? 'foo' : y ? 'foo' : 'fo'+'o';
+
+        // Compress conditions that have side effects
+        if (condition()) {
+            x = 10+10;
+        } else {
+            x = 20;
+        }
+
+        if (z) {
+            x = 'fuji';
+        } else if (condition()) {
+            x = 'fu'+'ji';
+        } else {
+            x = 'fuji';
+        }
+
+        x = condition() ? 'foobar' : 'foo'+'bar';
+
+        // don't compress these
+        x = y ? a : b;
+
+        x = y ? 'foo' : 'fo';
+    }
+    expect: {
+        var x, y, z, a, b;
+        x = 2;
+        x = 2;
+        x = 'foo';
+        x = 'foo';
+        x = (condition(), 20);
+        x = z ? 'fuji' : (condition(), 'fuji');
+        x = (condition(), 'foobar');
+        x = y ? a : b;
+        x = y ? 'foo' : 'fo';
+    }
+}
+
+cond_7_1: {
+    options = {
+        conditionals: true,
+        evaluate    : true
+    };
+    input: {
+        var x;
+        // access to global should be assumed to have side effects
+        if (y) {
+            x = 1+1;
+        } else {
+            x = 2;
+        }
+    }
+    expect: {
+        var x;
+        x = (y, 2);
+    }
+}
+
+cond_8: {
+    options = {
+        conditionals: true,
+        evaluate    : true,
+        booleans    : false
+    };
+    input: {
+        var a;
+        // compress these
+        a = condition ? true : false;
+        a = !condition ? true : false;
+        a = condition() ? true : false;
+
+        a = condition ? !0 : !1;
+        a = !condition ? !null : !2;
+        a = condition() ? !0 : !-3.5;
+
+        if (condition) {
+            a = true;
+        } else {
+            a = false;
+        }
+
+        if (condition) {
+            a = !0;
+        } else {
+            a = !1;
+        }
+
+        a = condition ? false : true;
+        a = !condition ? false : true;
+        a = condition() ? false : true;
+
+        a = condition ? !3 : !0;
+        a = !condition ? !2 : !0;
+        a = condition() ? !1 : !0;
+
+        if (condition) {
+            a = false;
+        } else {
+            a = true;
+        }
+
+        if (condition) {
+            a = !1;
+        } else {
+            a = !0;
+        }
+
+        // don't compress these
+        a = condition ? 1 : false;
+        a = !condition ? true : 0;
+        a = condition ? 1 : 0;
+    }
+    expect: {
+        var a;
+        a = !!condition;
+        a = !condition;
+        a = !!condition();
+
+        a = !!condition;
+        a = !condition;
+        a = !!condition();
+
+        a = !!condition;
+        a = !!condition;
+
+        a = !condition;
+        a = !!condition;
+        a = !condition();
+
+        a = !condition;
+        a = !!condition;
+        a = !condition();
+
+        a = !condition;
+        a = !condition;
+
+        a = !!condition && 1;
+        a = !condition || 0;
+        a = condition ? 1 : 0;
+    }
+}
+
+cond_8b: {
+    options = {
+        conditionals: true,
+        evaluate    : true,
+        booleans    : true
+    };
+    input: {
+        var a;
+        // compress these
+        a = condition ? true : false;
+        a = !condition ? true : false;
+        a = condition() ? true : false;
+
+        a = condition ? !0 : !1;
+        a = !condition ? !null : !2;
+        a = condition() ? !0 : !-3.5;
+
+        if (condition) {
+            a = true;
+        } else {
+            a = false;
+        }
+
+        if (condition) {
+            a = !0;
+        } else {
+            a = !1;
+        }
+
+        a = condition ? false : true;
+        a = !condition ? false : true;
+        a = condition() ? false : true;
+
+        a = condition ? !3 : !0;
+        a = !condition ? !2 : !0;
+        a = condition() ? !1 : !0;
+
+        if (condition) {
+            a = false;
+        } else {
+            a = true;
+        }
+
+        if (condition) {
+            a = !1;
+        } else {
+            a = !0;
+        }
+
+        a = condition ? 1 : false;
+        a = !condition ? true : 0;
+        a = condition ? 1 : 0;
+    }
+    expect: {
+        var a;
+        a = !!condition;
+        a = !condition;
+        a = !!condition();
+
+        a = !!condition;
+        a = !condition;
+        a = !!condition();
+
+        a = !!condition;
+        a = !!condition;
+
+        a = !condition;
+        a = !!condition;
+        a = !condition();
+
+        a = !condition;
+        a = !!condition;
+        a = !condition();
+
+        a = !condition;
+        a = !condition;
+
+        a = !!condition && 1;
+        a = !condition || 0;
+        a = condition ? 1 : 0;
+    }
+}
+
+cond_8c: {
+    options = {
+        conditionals: true,
+        evaluate    : false,
+        booleans    : false
+    };
+    input: {
+        var a;
+        // compress these
+        a = condition ? true : false;
+        a = !condition ? true : false;
+        a = condition() ? true : false;
+
+        a = condition ? !0 : !1;
+        a = !condition ? !null : !2;
+        a = condition() ? !0 : !-3.5;
+
+        if (condition) {
+            a = true;
+        } else {
+            a = false;
+        }
+
+        if (condition) {
+            a = !0;
+        } else {
+            a = !1;
+        }
+
+        a = condition ? false : true;
+        a = !condition ? false : true;
+        a = condition() ? false : true;
+
+        a = condition ? !3 : !0;
+        a = !condition ? !2 : !0;
+        a = condition() ? !1 : !0;
+
+        if (condition) {
+            a = false;
+        } else {
+            a = true;
+        }
+
+        if (condition) {
+            a = !1;
+        } else {
+            a = !0;
+        }
+
+        a = condition ? 1 : false;
+        a = !condition ? true : 0;
+        a = condition ? 1 : 0;
+    }
+    expect: {
+        var a;
+        a = !!condition;
+        a = !condition;
+        a = !!condition();
+
+        a = !!condition;
+        a = !condition;
+        a = !!condition() || !-3.5;
+
+        a = !!condition;
+        a = !!condition;
+
+        a = !condition;
+        a = !!condition;
+        a = !condition();
+
+        a = !condition;
+        a = !!condition;
+        a = !condition();
+
+        a = !condition;
+        a = !condition;
+
+        a = !!condition && 1;
+        a = !condition || 0;
+        a = condition ? 1 : 0;
+    }
+}
+
+ternary_boolean_consequent: {
+    options = {
+        collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
+        comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true
+    }
+    input: {
+        function f1() { return a == b ? true : x; }
+        function f2() { return a == b ? false : x; }
+        function f3() { return a < b ? !0 : x; }
+        function f4() { return a < b ? !1 : x; }
+        function f5() { return c ? !0 : x; }
+        function f6() { return c ? false : x; }
+        function f7() { return !c ? true : x; }
+        function f8() { return !c ? !1 : x; }
+    }
+    expect: {
+        function f1() { return a == b || x; }
+        function f2() { return a != b && x; }
+        function f3() { return a < b || x; }
+        function f4() { return !(a < b) && x; }
+        function f5() { return !!c || x; }
+        function f6() { return !c && x; }
+        function f7() { return !c || x; }
+        function f8() { return !!c && x; }
+    }
+}
+
+ternary_boolean_alternative: {
+    options = {
+        collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
+        comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true
+    }
+    input: {
+        function f1() { return a == b ? x : true; }
+        function f2() { return a == b ? x : false; }
+        function f3() { return a < b ? x : !0; }
+        function f4() { return a < b ? x : !1; }
+        function f5() { return c ? x : true; }
+        function f6() { return c ? x : !1; }
+        function f7() { return !c ? x : !0; }
+        function f8() { return !c ? x : false; }
+    }
+    expect: {
+        function f1() { return a != b || x; }
+        function f2() { return a == b && x; }
+        function f3() { return !(a < b) || x; }
+        function f4() { return a < b && x; }
+        function f5() { return !c || x; }
+        function f6() { return !!c && x; }
+        function f7() { return !!c || x; }
+        function f8() { return !c && x; }
+    }
+}
+
+trivial_boolean_ternary_expressions : {
+    options = {
+        conditionals: true,
+        evaluate    : true,
+        booleans    : true
+    };
+    input: {
+        f('foo' in m ? true  : false);
+        f('foo' in m ? false : true);
+
+        f(g       ? true : false);
+        f(foo()   ? true : false);
+        f("bar"   ? true : false);
+        f(5       ? true : false);
+        f(5.7     ? true : false);
+        f(x - y   ? true : false);
+
+        f(x == y  ? true : false);
+        f(x === y ?   !0 :    !1);
+        f(x < y   ?   !0 : false);
+        f(x <= y  ? true : false);
+        f(x > y   ? true :    !1);
+        f(x >= y  ?   !0 :    !1);
+
+        f(g       ? false : true);
+        f(foo()   ? false : true);
+        f("bar"   ? false : true);
+        f(5       ? false : true);
+        f(5.7     ? false : true);
+        f(x - y   ? false : true);
+
+        f(x == y  ?    !1 :   !0);
+        f(x === y ? false : true);
+
+        f(x < y   ? false : true);
+        f(x <= y  ? false :   !0);
+        f(x > y   ?    !1 : true);
+        f(x >= y  ?    !1 :   !0);
+    }
+    expect: {
+        f('foo' in m);
+        f(!('foo' in m));
+
+        f(!!g);
+        f(!!foo());
+        f(!0);
+        f(!0);
+        f(!0);
+        f(!!(x - y));
+
+        f(x == y);
+        f(x === y);
+        f(x < y);
+        f(x <= y);
+        f(x > y);
+        f(x >= y);
+
+        f(!g);
+        f(!foo());
+        f(!1);
+        f(!1);
+        f(!1);
+        f(!(x - y));
+
+        f(x != y);
+        f(x !== y);
+
+        f(!(x < y));
+        f(!(x <= y));
+        f(!(x > y));
+        f(!(x >= y));
+    }
+}
+
+issue_1154: {
+    options = {
+        conditionals: true,
+        evaluate    : true,
+        booleans    : true,
+        side_effects: true,
+    };
+    input: {
+        function f1(x) { return x ? -1 : -1; }
+        function f2(x) { return x ? +2 : +2; }
+        function f3(x) { return x ? ~3 : ~3; }
+        function f4(x) { return x ? !4 : !4; }
+        function f5(x) { return x ? void 5 : void 5; }
+        function f6(x) { return x ? typeof 6 : typeof 6; }
+
+        function g1() { return g() ? -1 : -1; }
+        function g2() { return g() ? +2 : +2; }
+        function g3() { return g() ? ~3 : ~3; }
+        function g4() { return g() ? !4 : !4; }
+        function g5() { return g() ? void 5 : void 5; }
+        function g6() { return g() ? typeof 6 : typeof 6; }
+    }
+    expect: {
+        function f1(x) { return -1; }
+        function f2(x) { return 2; }
+        function f3(x) { return -4; }
+        function f4(x) { return !1; }
+        function f5(x) { return; }
+        function f6(x) { return "number"; }
+
+        function g1() { return g(), -1; }
+        function g2() { return g(), 2; }
+        function g3() { return g(), -4; }
+        function g4() { return g(), !1; }
+        function g5() { return void g(); }
+        function g6() { return g(), "number"; }
+    }
+}
+
+no_evaluate: {
+    options = {
+        conditionals: true,
+        evaluate    : false,
+        side_effects: true,
+    }
+    input: {
+        function f(b) {
+            a = b ? !0 : !0;
+            a = b ? ~1 : ~1;
+            a = b ? -2 : -2;
+            a = b ? +3 : +3;
+        }
+    }
+    expect: {
+        function f(b) {
+            a = !0;
+            a = ~1;
+            a = -2;
+            a = +3;
+        }
+    }
+}
+
+equality_conditionals_false: {
+    options = {
+        conditionals: false,
+        sequences: true,
+    }
+    input: {
+        function f(a, b, c) {
+            console.log(
+                a == (b ? a : a),
+                a == (b ? a : c),
+                a != (b ? a : a),
+                a != (b ? a : c),
+                a === (b ? a : a),
+                a === (b ? a : c),
+                a !== (b ? a : a),
+                a !== (b ? a : c)
+            );
+        }
+        f(0, 0, 0);
+        f(0, true, 0);
+        f(1, 2, 3);
+        f(1, null, 3);
+        f(NaN);
+        f(NaN, "foo");
+    }
+    expect: {
+        function f(a, b, c) {
+            console.log(
+                a == (b ? a : a),
+                a == (b ? a : c),
+                a != (b ? a : a),
+                a != (b ? a : c),
+                a === (b ? a : a),
+                a === (b ? a : c),
+                a !== (b ? a : a),
+                a !== (b ? a : c)
+            );
+        }
+        f(0, 0, 0),
+        f(0, true, 0),
+        f(1, 2, 3),
+        f(1, null, 3),
+        f(NaN),
+        f(NaN, "foo");
+    }
+    expect_stdout: true
+}
+
+equality_conditionals_true: {
+    options = {
+        conditionals: true,
+        sequences: true,
+    }
+    input: {
+        function f(a, b, c) {
+            console.log(
+                a == (b ? a : a),
+                a == (b ? a : c),
+                a != (b ? a : a),
+                a != (b ? a : c),
+                a === (b ? a : a),
+                a === (b ? a : c),
+                a !== (b ? a : a),
+                a !== (b ? a : c)
+            );
+        }
+        f(0, 0, 0);
+        f(0, true, 0);
+        f(1, 2, 3);
+        f(1, null, 3);
+        f(NaN);
+        f(NaN, "foo");
+    }
+    expect: {
+        function f(a, b, c) {
+            console.log(
+                (b, a == a),
+                a == (b ? a : c),
+                (b, a != a),
+                a != (b ? a : c),
+                (b, a === a),
+                a === (b ? a : c),
+                (b, a !== a),
+                a !== (b ? a : c)
+            );
+        }
+        f(0, 0, 0),
+        f(0, true, 0),
+        f(1, 2, 3),
+        f(1, null, 3),
+        f(NaN),
+        f(NaN, "foo");
+    }
+    expect_stdout: true
+}

test/compress/const.js

@@ -0,0 +1,166 @@
+issue_1191: {
+    options = {
+        evaluate      : true,
+        booleans      : true,
+        comparisons   : true,
+        dead_code     : true,
+        conditionals  : true,
+        side_effects  : true,
+        unused        : true,
+        hoist_funs    : true,
+        if_return     : true,
+        join_vars     : true,
+        sequences     : false,
+        collapse_vars : false,
+        reduce_vars   : true,
+    }
+    input: {
+        function foo(rot) {
+            const rotTol = 5;
+            if (rot < -rotTol || rot > rotTol)
+                bar();
+            baz();
+        }
+    }
+    expect: {
+        function foo(rot) {
+            (rot < -5 || rot > 5) && bar();
+            baz();
+        }
+    }
+}
+
+issue_1194: {
+    options = {
+        evaluate      : true,
+        booleans      : true,
+        comparisons   : true,
+        dead_code     : true,
+        conditionals  : true,
+        side_effects  : true,
+        unused        : true,
+        hoist_funs    : true,
+        if_return     : true,
+        join_vars     : true,
+        sequences     : false,
+        collapse_vars : false,
+        reduce_vars   : true,
+    }
+    input: {
+        function f1() {const a = "X"; return a + a;}
+        function f2() {const aa = "X"; return aa + aa;}
+        function f3() {const aaa = "X"; return aaa + aaa;}
+    }
+    expect: {
+        function f1(){return"XX"}
+        function f2(){return"XX"}
+        function f3(){return"XX"}
+    }
+}
+
+issue_1396: {
+    options = {
+        evaluate      : true,
+        booleans      : true,
+        comparisons   : true,
+        dead_code     : true,
+        conditionals  : true,
+        side_effects  : true,
+        unused        : true,
+        hoist_funs    : true,
+        if_return     : true,
+        join_vars     : true,
+        sequences     : false,
+        collapse_vars : false,
+        reduce_vars   : true,
+    }
+    input: {
+        function foo(a) {
+            const VALUE = 1;
+            console.log(2 | VALUE);
+            console.log(VALUE + 1);
+            console.log(VALUE);
+            console.log(a & VALUE);
+        }
+        function bar() {
+            const s = "01234567890123456789";
+            console.log(s + s + s + s + s);
+
+            const CONSTANT = "abc";
+            console.log(CONSTANT + CONSTANT + CONSTANT + CONSTANT + CONSTANT);
+        }
+    }
+    expect: {
+        function foo(a) {
+            console.log(3);
+            console.log(2);
+            console.log(1);
+            console.log(1 & a);
+        }
+        function bar() {
+            const s = "01234567890123456789";
+            console.log(s + s + s + s + s);
+
+            console.log("abcabcabcabcabc");
+        }
+    }
+}
+
+unused_regexp_literal: {
+    options = {
+        evaluate      : true,
+        booleans      : true,
+        comparisons   : true,
+        dead_code     : true,
+        conditionals  : true,
+        side_effects  : true,
+        unused        : true,
+        hoist_funs    : true,
+        if_return     : true,
+        join_vars     : true,
+        sequences     : false,
+        collapse_vars : false,
+    }
+    input: {
+        function f(){ var a = /b/; }
+    }
+    expect: {
+        function f(){}
+    }
+}
+
+regexp_literal_not_const: {
+    options = {
+        evaluate      : true,
+        booleans      : true,
+        comparisons   : true,
+        dead_code     : true,
+        conditionals  : true,
+        side_effects  : true,
+        unused        : true,
+        hoist_funs    : true,
+        if_return     : true,
+        join_vars     : true,
+        sequences     : false,
+        collapse_vars : false,
+        reduce_vars   : true,
+    }
+    input: {
+        (function(){
+            var result;
+            const s = 'acdabcdeabbb';
+            const REGEXP_LITERAL = /ab*/g;
+            while (result = REGEXP_LITERAL.exec(s)) {
+                console.log(result[0]);
+            }
+        })();
+    }
+    expect: {
+        (function() {
+            var result;
+            const REGEXP_LITERAL = /ab*/g;
+            while (result = REGEXP_LITERAL.exec("acdabcdeabbb")) console.log(result[0]);
+        })();
+    }
+    expect_stdout: true
+}

test/compress/dead-code.js

@@ -64,7 +64,8 @@ dead_code_constant_boolean_should_warn_more: {
         loops        : true,
         booleans     : true,
         conditionals : true,
-        evaluate     : true
+        evaluate     : true,
+        side_effects : true,
     };
     input: {
         while (!((foo && bar) || (x + "0"))) {
@@ -72,7 +73,7 @@ dead_code_constant_boolean_should_warn_more: {
             var foo;
             function bar() {}
         }
-        for (var x = 10; x && (y || x) && (!typeof x); ++x) {
+        for (var x = 10, y; x && (y || x) && (!typeof x); ++x) {
             asdf();
             foo();
             var moo;
@@ -83,7 +84,155 @@ dead_code_constant_boolean_should_warn_more: {
         function bar() {}
         // nothing for the while
         // as for the for, it should keep:
-        var x = 10;
+        var x = 10, y;
         var moo;
     }
+    expect_stdout: true
+}
+
+dead_code_block_decls_die: {
+    options = {
+        dead_code    : true,
+        conditionals : true,
+        booleans     : true,
+        evaluate     : true
+    };
+    input: {
+        if (0) {
+            let foo = 6;
+            const bar = 12;
+            class Baz {};
+            var qux;
+        }
+        console.log(foo, bar, Baz);
+    }
+    expect: {
+        var qux;
+        console.log(foo, bar, Baz);
+    }
+}
+
+dead_code_const_declaration: {
+    options = {
+        dead_code    : true,
+        loops        : true,
+        booleans     : true,
+        conditionals : true,
+        evaluate     : true,
+        reduce_vars  : true,
+    };
+    input: {
+        var unused;
+        const CONST_FOO = false;
+        if (CONST_FOO) {
+            console.log("unreachable");
+            var moo;
+            function bar() {}
+        }
+    }
+    expect: {
+        var unused;
+        const CONST_FOO = !1;
+        var moo;
+        function bar() {}
+    }
+    expect_stdout: true
+}
+
+dead_code_const_annotation: {
+    options = {
+        dead_code    : true,
+        loops        : true,
+        booleans     : true,
+        conditionals : true,
+        evaluate     : true,
+        reduce_vars  : true,
+        toplevel     : true,
+    };
+    input: {
+        var unused;
+        /** @const */ var CONST_FOO_ANN = false;
+        if (CONST_FOO_ANN) {
+            console.log("unreachable");
+            var moo;
+            function bar() {}
+        }
+    }
+    expect: {
+        var unused;
+        var CONST_FOO_ANN = !1;
+        var moo;
+        function bar() {}
+    }
+    expect_stdout: true
+}
+
+dead_code_const_annotation_regex: {
+    options = {
+        dead_code    : true,
+        loops        : true,
+        booleans     : true,
+        conditionals : true,
+        evaluate     : true
+    };
+    input: {
+        var unused;
+        // @constraint this shouldn't be a constant
+        var CONST_FOO_ANN = false;
+        if (CONST_FOO_ANN) {
+            console.log("reachable");
+        }
+    }
+    expect: {
+        var unused;
+        var CONST_FOO_ANN = !1;
+        CONST_FOO_ANN && console.log('reachable');
+    }
+    expect_stdout: true
+}
+
+dead_code_const_annotation_complex_scope: {
+    options = {
+        dead_code    : true,
+        loops        : true,
+        booleans     : true,
+        conditionals : true,
+        evaluate     : true,
+        reduce_vars  : true,
+        toplevel     : true,
+    };
+    input: {
+        var unused_var;
+        /** @const */ var test = 'test';
+        // @const
+        var CONST_FOO_ANN = false;
+        var unused_var_2;
+        if (CONST_FOO_ANN) {
+            console.log("unreachable");
+            var moo;
+            function bar() {}
+        }
+        if (test === 'test') {
+            var beef = 'good';
+            /** @const */ var meat = 'beef';
+            var pork = 'bad';
+            if (meat === 'pork') {
+                console.log('also unreachable');
+            } else if (pork === 'good') {
+                console.log('reached, not const');
+            }
+        }
+    }
+    expect: {
+        var unused_var;
+        var test = 'test';
+        var CONST_FOO_ANN = !1;
+        var unused_var_2;
+        var moo;
+        function bar() {}
+        var beef = 'good';
+        var meat = 'beef';
+        var pork = 'bad';
+    }
+    expect_stdout: true
 }

test/compress/destructuring.js

@@ -0,0 +1,309 @@
+destructuring_arrays: {
+    input: {
+        {const [aa, bb] = cc;}
+        {const [aa, [bb, cc]] = dd;}
+        {let [aa, bb] = cc;}
+        {let [aa, [bb, cc]] = dd;}
+        var [aa, bb] = cc;
+        var [aa, [bb, cc]] = dd;
+        var [,[,,,,,],,,zz,] = xx; // Trailing comma
+        var [,,zzz,,] = xxx; // Trailing comma after hole
+    }
+    expect: {
+        {const [aa, bb] = cc;}
+        {const [aa, [bb, cc]] = dd;}
+        {let [aa, bb] = cc;}
+        {let [aa, [bb, cc]] = dd;}
+        var [aa, bb] = cc;
+        var [aa, [bb, cc]] = dd;
+        var [,[,,,,,],,,zz] = xx;
+        var [,,zzz,,] = xxx;
+    }
+}
+
+destructuring_arrays_holes: {
+    input: {
+        var [,,,,] = a;
+        var [,,b,] = c;
+        var [d,,]  = e;
+    }
+    expect_exact: "var[,,,,]=a;var[,,b]=c;var[d,,]=e;"
+}
+
+destructuring_objects: {
+    input: {
+        {const {aa, bb} = {aa:1, bb:2};}
+        {const {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        {let {aa, bb} = {aa:1, bb:2};}
+        {let {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        var {aa, bb} = {aa:1, bb:2};
+        var {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};
+    }
+    expect: {
+        {const {aa, bb} = {aa:1, bb:2};}
+        {const {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        {let {aa, bb} = {aa:1, bb:2};}
+        {let {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        var {aa, bb} = {aa:1, bb:2};
+        var {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};
+    }
+}
+
+destructuring_objects_trailing_elision: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        var {cc,} = foo;
+    }
+    expect_exact: "var{cc}=foo;"
+}
+
+nested_destructuring_objects: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        const [{a},b] = c;
+        let [{a},b] = c;
+        var [{a},b] = c;
+    }
+    expect_exact: 'const[{a},b]=c;let[{a},b]=c;var[{a},b]=c;';
+}
+
+destructuring_constdef_in_loops: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        for (const [x,y] in pairs);
+        for (const [a] = 0;;);
+        for (const {c} of cees);
+    }
+    expect_exact: "for(const[x,y]in pairs);for(const[a]=0;;);for(const{c}of cees);"
+}
+
+destructuring_letdef_in_loops: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        for (let [x,y] in pairs);
+        for (let [a] = 0;;);
+        for (let {c} of cees);
+    }
+    expect_exact: "for(let[x,y]in pairs);for(let[a]=0;;);for(let{c}of cees);"
+}
+
+destructuring_vardef_in_loops: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        for (var [x,y] in pairs);
+        for (var [a] = 0;;);
+        for (var {c} of cees);
+    }
+    expect_exact: "for(var[x,y]in pairs);for(var[a]=0;;);for(var{c}of cees);"
+}
+
+destructuring_expressions: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        ({a, b});
+        [{a}];
+        f({x});
+    }
+    expect_exact: "({a,b});[{a}];f({x});"
+}
+
+destructuring_remove_unused_1: {
+    options = {
+        unused: true
+    }
+    input: {
+        function a() {
+            var unused = "foo";
+            var a = [1];
+            var [b] = a;
+            f(b);
+        }
+        function b() {
+            var unused = "foo";
+            var a = {b: 1};
+            var {b} = a;
+            f(b);
+        }
+        function c() {
+            var unused = "foo";
+            var a = [[1]];
+            var [[b]] = a;
+            f(b);
+        }
+        function d() {
+            var unused = "foo";
+            var a = {b: {b:1}};
+            var {b:{b}} = a;
+            f(b);
+        }
+        function e() {
+            var unused = "foo";
+            var a = [1, 2, 3, 4, 5];
+            var [b, ...c] = a;
+            f(b, c);
+        }
+    }
+    expect: {
+        function a() {
+            var a = [1];
+            var [b] = a;
+            f(b);
+        }
+        function b() {
+            var a = {b: 1};
+            var {b} = a;
+            f(b);
+        }
+        function c() {
+            var a = [[1]];
+            var [[b]] = a;
+            f(b);
+        }
+        function d() {
+            var a = {b: {b:1}};
+            var {b:{b}} = a;
+            f(b);
+        }
+        function e() {
+            var a = [1, 2, 3, 4, 5];
+            var [b, ...c] = a;
+            f(b, c);
+        }
+    }
+}
+
+destructuring_remove_unused_2: {
+    options = {
+        unused: true
+    }
+    input: {
+        function a() {
+            var unused = "foo";
+            var a = [,,1];
+            var [b] = a;
+            f(b);
+        }
+        function b() {
+            var unused = "foo";
+            var a = [{a: [1]}];
+            var [{b: a}] = a;
+            f(b);
+        }
+    }
+    expect: {
+        function a() {
+            var a = [,,1];
+            var [b] = a;
+            f(b);
+        }
+        function b() {
+            var a = [{a: [1]}];
+            var [{b: a}] = a;
+            f(b);
+        }
+    }
+}
+
+object_destructuring_may_need_parentheses: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        ({a, b} = {a: 1, b: 2});
+    }
+    expect_exact: "({a,b}={a:1,b:2});"
+}
+
+destructuring_with_undefined_as_default_assignment: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        [foo = undefined] = bar;
+        [foo = void 0] = bar;
+    }
+    expect: {
+        [foo] = bar;
+        [foo] = bar;
+    }
+}
+
+destructuring_dont_evaluate_with_undefined_as_default_assignment: {
+    options = {
+        evaluate: false
+    }
+    input: {
+        [foo = undefined] = bar;
+    }
+    expect: {
+        [foo = void 0] = bar;
+    }
+}
+
+reduce_vars: {
+    options = {
+        reduce_vars: true,
+    }
+    input: {
+        {const [aa, [bb, cc]] = dd;}
+        {let [aa, [bb, cc]] = dd;}
+        var [aa, [bb, cc]] = dd;
+        [aa, [bb, cc]] = dd;
+        {const {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        {let {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        var {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};
+        ({aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}});
+        const [{a},b] = c;
+        let [{a},b] = c;
+        var [{a},b] = c;
+        [{a},b] = c;
+        for (const [x,y] in pairs);
+        for (let [x,y] in pairs);
+        for (var [x,y] in pairs);
+        for ([x,y] in pairs);
+    }
+    expect: {
+        {const [aa, [bb, cc]] = dd;}
+        {let [aa, [bb, cc]] = dd;}
+        var [aa, [bb, cc]] = dd;
+        [aa, [bb, cc]] = dd;
+        {const {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        {let {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        var {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};
+        ({aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}});
+        const [{a},b] = c;
+        let [{a},b] = c;
+        var [{a},b] = c;
+        [{a},b] = c;
+        for (const [x,y] in pairs);
+        for (let [x,y] in pairs);
+        for (var [x,y] in pairs);
+        for ([x,y] in pairs);
+    }
+}
+
+unused: {
+    options = {
+        unused: true,
+    }
+    input: {
+        let { foo: [, , ...a] } = { foo: [1, 2, 3, 4], bar: 5 };
+        console.log(a);
+    }
+    expect: {
+        let { foo: [, , ...a] } = { foo: [1, 2, 3, 4], bar: 5 };
+        console.log(a);
+    }
+}

test/compress/directives.js

@@ -0,0 +1,10 @@
+class_directives_compression: {
+    input: {
+        class foo {
+            foo() {
+                "use strict";
+            }
+        }
+    }
+    expect_exact: "class foo{foo(){}}"
+}

test/compress/drop-console.js

@@ -0,0 +1,24 @@
+drop_console_1: {
+    options = {};
+    input: {
+        console.log('foo');
+        console.log.apply(console, arguments);
+    }
+    expect: {
+        console.log('foo');
+        console.log.apply(console, arguments);
+    }
+}
+
+drop_console_2: {
+    options = { drop_console: true };
+    input: {
+        console.log('foo');
+        console.log.apply(console, arguments);
+    }
+    expect: {
+        // with regular compression these will be stripped out as well
+        void 0;
+        void 0;
+    }
+}

test/compress/drop-unused.js

@@ -1,5 +1,5 @@
 unused_funarg_1: {
-    options = { unused: true };
+    options = { unused: true, keep_fargs: false };
     input: {
         function f(a, b, c, d, e) {
             return a + b;
@@ -13,7 +13,7 @@ unused_funarg_1: {
 }
 
 unused_funarg_2: {
-    options = { unused: true };
+    options = { unused: true, keep_fargs: false };
     input: {
         function f(a, b, c, d, e) {
             return a + c;
@@ -95,3 +95,780 @@ unused_circular_references_3: {
         }
     }
 }
+
+unused_keep_setter_arg: {
+    options = { unused: true };
+    input: {
+        var x = {
+            _foo: null,
+            set foo(val) {
+            },
+            get foo() {
+                return this._foo;
+            }
+        }
+    }
+    expect: {
+        var x = {
+            _foo: null,
+            set foo(val) {
+            },
+            get foo() {
+                return this._foo;
+            }
+        }
+    }
+}
+
+unused_var_in_catch: {
+    options = { unused: true };
+    input: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {
+                var x = 10;
+            }
+        }
+    }
+    expect: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {}
+        }
+    }
+}
+
+used_var_in_catch: {
+    options = { unused: true };
+    input: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {
+                var x = 10;
+            }
+            return x;
+        }
+    }
+    expect: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {
+                var x = 10;
+            }
+            return x;
+        }
+    }
+}
+
+unused_block_decls_in_catch: {
+    options = { unused: true };
+    input: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {
+                let x = 10;
+                const y = 10;
+                class Zee {};
+            }
+        }
+    }
+    expect: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {}
+        }
+    }
+}
+
+used_block_decls_in_catch: {
+    options = { unused: true };
+    input: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {
+                let x = 10;
+                const y = 10;
+                class Zee {};
+            }
+            console.log(x, y, Zee);
+        }
+    }
+    expect: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {}
+            console.log(x, y, Zee);
+        }
+    }
+}
+
+unused_block_decls: {
+    options = { unused: true };
+    input: {
+        function foo() {
+            {
+                const x;
+            }
+            {
+                let y;
+            }
+            console.log(x, y);
+        }
+    }
+    expect: {
+        function foo() {
+            console.log(x, y);
+        }
+    }
+}
+
+unused_keep_harmony_destructuring: {
+    options = { unused: true };
+    input: {
+        function foo() {
+            var {x, y} = foo;
+            var a = foo;
+        }
+    }
+    expect:  {
+        function foo() {
+            var {x, y} = foo;
+        }
+    }
+}
+
+keep_fnames: {
+    options = { unused: true, keep_fnames: true, unsafe: true };
+    input: {
+        function foo() {
+            return function bar(baz) {};
+        }
+    }
+    expect: {
+        function foo() {
+            return function bar(baz) {};
+        }
+    }
+}
+
+drop_assign: {
+    options = { unused: true };
+    input: {
+        function f1() {
+            var a;
+            a = 1;
+        }
+        function f2() {
+            var a = 1;
+            a = 2;
+        }
+        function f3(a) {
+            a = 1;
+        }
+        function f4() {
+            var a;
+            return a = 1;
+        }
+        function f5() {
+            var a;
+            return function() {
+                a = 1;
+            }
+        }
+    }
+    expect: {
+        function f1() {
+            1;
+        }
+        function f2() {
+            2;
+        }
+        function f3(a) {
+            1;
+        }
+        function f4() {
+            return 1;
+        }
+        function f5() {
+            var a;
+            return function() {
+                a = 1;
+            }
+        }
+    }
+}
+
+keep_assign: {
+    options = { unused: "keep_assign" };
+    input: {
+        function f1() {
+            var a;
+            a = 1;
+        }
+        function f2() {
+            var a = 1;
+            a = 2;
+        }
+        function f3(a) {
+            a = 1;
+        }
+        function f4() {
+            var a;
+            return a = 1;
+        }
+        function f5() {
+            var a;
+            return function() {
+                a = 1;
+            }
+        }
+    }
+    expect: {
+        function f1() {
+            var a;
+            a = 1;
+        }
+        function f2() {
+            var a = 1;
+            a = 2;
+        }
+        function f3(a) {
+            a = 1;
+        }
+        function f4() {
+            var a;
+            return a = 1;
+        }
+        function f5() {
+            var a;
+            return function() {
+                a = 1;
+            }
+        }
+    }
+}
+
+drop_toplevel_funcs: {
+    options = { toplevel: "funcs", unused: true };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        var a, b = 1, c = g;
+        a = 2;
+        function g() {}
+        console.log(b = 3);
+    }
+}
+
+drop_toplevel_vars: {
+    options = { toplevel: "vars", unused: true };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        var c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        2;
+        function g() {}
+        function h() {}
+        console.log(3);
+    }
+}
+
+drop_toplevel_vars_fargs: {
+    options = { keep_fargs: false, toplevel: "vars", unused: true };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        var c = g;
+        function f() {
+            return function() {
+                c = 2;
+            }
+        }
+        2;
+        function g() {}
+        function h() {}
+        console.log(3);
+    }
+}
+
+drop_toplevel_all: {
+    options = { toplevel: true, unused: true };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        2;
+        console.log(3);
+    }
+}
+
+drop_toplevel_retain: {
+    options = { top_retain: "f,a,o", unused: true };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        var a, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        console.log(3);
+    }
+}
+
+drop_toplevel_retain_array: {
+    options = { top_retain: [ "f", "a", "o" ], unused: true };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        var a, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        console.log(3);
+    }
+}
+
+drop_toplevel_retain_regex: {
+    options = { top_retain: /^[fao]$/, unused: true };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        var a, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        console.log(3);
+    }
+}
+
+drop_toplevel_all_retain: {
+    options = { toplevel: true, top_retain: "f,a,o", unused: true };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        var a, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        console.log(3);
+    }
+}
+
+drop_toplevel_funcs_retain: {
+    options = { toplevel: "funcs", top_retain: "f,a,o", unused: true };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        console.log(b = 3);
+    }
+}
+
+drop_toplevel_vars_retain: {
+    options = { toplevel: "vars", top_retain: "f,a,o", unused: true };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        var a, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(3);
+    }
+}
+
+drop_toplevel_keep_assign: {
+    options = { toplevel: true, unused: "keep_assign" };
+    input: {
+        var a, b = 1, c = g;
+        function f(d) {
+            return function() {
+                c = 2;
+            }
+        }
+        a = 2;
+        function g() {}
+        function h() {}
+        console.log(b = 3);
+    }
+    expect: {
+        var a, b = 1;
+        a = 2;
+        console.log(b = 3);
+    }
+}
+
+drop_fargs: {
+    options = {
+        keep_fargs: false,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            var b = a;
+        }
+    }
+    expect: {
+        function f() {}
+    }
+}
+
+drop_fnames: {
+    options = {
+        keep_fnames: false,
+        unused: true,
+    }
+    input: {
+        function f() {
+            return function g() {
+                var a = g;
+            };
+        }
+    }
+    expect: {
+        function f() {
+            return function() {};
+        }
+    }
+}
+
+global_var: {
+    options = {
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        function foo(b) {
+            a;
+            b;
+            c;
+            typeof c === "undefined";
+            c + b + a;
+            b && b.ar();
+            return b;
+        }
+    }
+    expect: {
+        var a;
+        function foo(b) {
+            c;
+            c;
+            b && b.ar();
+            return b;
+        }
+    }
+}
+
+iife: {
+    options = {
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            var a;
+            ~function() {}(b);
+        }
+    }
+    expect: {
+        function f() {
+            b;
+        }
+    }
+}
+
+drop_value: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        (1, [2, foo()], 3, {a:1, b:bar()});
+    }
+    expect: {
+        foo(), bar();
+    }
+}
+
+const_assign: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            const b = 2;
+            return 1 + b;
+        }
+
+        function g() {
+            const b = 2;
+            b = 3;
+            return 1 + b;
+        }
+    }
+    expect: {
+        function f() {
+            return 3;
+        }
+
+        function g() {
+            const b = 2;
+            b = 3;
+            return 1 + b;
+        }
+    }
+}
+
+issue_1539: {
+    options = {
+        cascade: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            var a, b;
+            a = b = 42;
+            return a;
+        }
+    }
+    expect: {
+        function f() {
+            return 42;
+        }
+    }
+}
+
+vardef_value: {
+    options = {
+        keep_fnames: false,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g(){
+                return x();
+            }
+            var a = g();
+            return a(42);
+        }
+    }
+    expect: {
+        function f() {
+            var a = function(){
+                return x();
+            }();
+            return a(42);
+        }
+    }
+}
+
+assign_binding: {
+    options = {
+        cascade: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            var a;
+            a = f.g, a();
+        }
+    }
+    expect: {
+        function f() {
+            (0, f.g)();
+        }
+    }
+}
+
+assign_chain: {
+    options = {
+        unused: true,
+    }
+    input: {
+        function f() {
+            var a, b;
+            x = a = y = b = 42;
+        }
+    }
+    expect: {
+        function f() {
+            x = y = 42;
+        }
+    }
+}
+
+issue_1583: {
+    options = {
+        keep_fargs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function m(t) {
+            (function(e) {
+                t = e();
+            })(function() {
+                return (function(a) {
+                    return a;
+                })(function(a) {});
+            });
+        }
+    }
+    expect: {
+        function m(t) {
+            (function(e) {
+                t = (function() {
+                    return (function(a) {
+                        return a;
+                    })(function(a) {});
+                })();
+            })();
+        }
+    }
+}

test/compress/evaluate.js

@@ -0,0 +1,885 @@
+and: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a;
+        // compress these
+
+        a = true     && condition;
+        a = 1        && console.log("a");
+        a = 2 * 3    && 2 * condition;
+        a = 5 == 5   && condition + 3;
+        a = "string" && 4 - condition;
+        a = 5 + ""   && condition / 5;
+        a = -4.5     && 6 << condition;
+        a = 6        && 7;
+
+        a = false     && condition;
+        a = NaN       && console.log("b");
+        a = 0         && console.log("c");
+        a = undefined && 2 * condition;
+        a = null      && condition + 3;
+        a = 2 * 3 - 6 && 4 - condition;
+        a = 10 == 7   && condition / 5;
+        a = !"string" && 6 % condition;
+        a = 0         && 7;
+
+        // don't compress these
+
+        a = condition        && true;
+        a = console.log("a") && 2;
+        a = 4 - condition    && "string";
+        a = 6 << condition   && -4.5;
+
+        a = condition        && false;
+        a = console.log("b") && NaN;
+        a = console.log("c") && 0;
+        a = 2 * condition    && undefined;
+        a = condition + 3    && null;
+
+    }
+    expect: {
+        var a;
+
+        a = condition;
+        a = console.log("a");
+        a = 2 * condition;
+        a = condition + 3;
+        a = 4 - condition;
+        a = condition / 5;
+        a = 6 << condition;
+        a = 7;
+
+        a = false;
+        a = NaN;
+        a = 0;
+        a = void 0;
+        a = null;
+        a = 0;
+        a = false;
+        a = false;
+        a = 0;
+
+        a = condition        && true;
+        a = console.log("a") && 2;
+        a = 4 - condition    && "string";
+        a = 6 << condition   && -4.5;
+
+        a = condition        && false;
+        a = console.log("b") && NaN;
+        a = console.log("c") && 0;
+        a = 2 * condition    && void 0;
+        a = condition + 3    && null;
+    }
+}
+
+or: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a;
+        // compress these
+
+        a = true     || condition;
+        a = 1        || console.log("a");
+        a = 2 * 3    || 2 * condition;
+        a = 5 == 5   || condition + 3;
+        a = "string" || 4 - condition;
+        a = 5 + ""   || condition / 5;
+        a = -4.5     || 6 << condition;
+        a = 6        || 7;
+
+        a = false     || condition;
+        a = 0         || console.log("b");
+        a = NaN       || console.log("c");
+        a = undefined || 2 * condition;
+        a = null      || condition + 3;
+        a = 2 * 3 - 6 || 4 - condition;
+        a = 10 == 7   || condition / 5;
+        a = !"string" || 6 % condition;
+        a = null      || 7;
+
+        a = console.log(undefined && condition || null);
+        a = console.log(undefined || condition && null);
+
+        // don't compress these
+
+        a = condition        || true;
+        a = console.log("a") || 2;
+        a = 4 - condition    || "string";
+        a = 6 << condition   || -4.5;
+
+        a = condition        || false;
+        a = console.log("b") || NaN;
+        a = console.log("c") || 0;
+        a = 2 * condition    || undefined;
+        a = condition + 3    || null;
+
+    }
+    expect: {
+        var a;
+
+        a = true;
+        a = 1;
+        a = 6;
+        a = true;
+        a = "string";
+        a = "5";
+        a = -4.5;
+        a = 6;
+
+        a = condition;
+        a = console.log("b");
+        a = console.log("c");
+        a = 2 * condition;
+        a = condition + 3;
+        a = 4 - condition;
+        a = condition / 5;
+        a = 6 % condition;
+        a = 7;
+
+        a = console.log(null);
+        a = console.log(condition && null);
+
+        a = condition        || true;
+        a = console.log("a") || 2;
+        a = 4 - condition    || "string";
+        a = 6 << condition   || -4.5;
+
+        a = condition        || false;
+        a = console.log("b") || NaN;
+        a = console.log("c") || 0;
+        a = 2 * condition    || void 0;
+        a = condition + 3    || null;
+    }
+}
+
+unary_prefix: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        a = !0 && b;
+        a = !0 || b;
+        a = ~1 && b;
+        a = ~1 || b;
+        a = -2 && b;
+        a = -2 || b;
+        a = +3 && b;
+        a = +3 || b;
+    }
+    expect: {
+        a = b;
+        a = !0;
+        a = b;
+        a = -2;
+        a = b;
+        a = -2;
+        a = b;
+        a = 3;
+    }
+}
+
+negative_zero: {
+    options = { evaluate: true }
+    input: {
+        console.log(
+            -"",
+            - -"",
+            1 / (-0),
+            1 / (-"")
+        );
+    }
+    expect: {
+        console.log(
+            -0,
+            0,
+            1 / (-0),
+            1 / (-0)
+        );
+    }
+    expect_stdout: true
+}
+
+positive_zero: {
+    options = { evaluate: true }
+    input: {
+        console.log(
+            +"",
+            + -"",
+            1 / (+0),
+            1 / (+"")
+        );
+    }
+    expect: {
+        console.log(
+            0,
+            -0,
+            1 / (0),
+            1 / (0)
+        );
+    }
+    expect_stdout: true
+}
+
+pow: {
+    options = { evaluate: true }
+    input: {
+        var a = 5 ** 3;
+    }
+    expect: {
+        var a = 125;
+    }
+}
+
+pow_sequence: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a = 2 ** 3 ** 2;
+    }
+    expect: {
+        var a = 512;
+    }
+}
+
+pow_mixed: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a = 5 + 2 ** 3 + 5;
+        var b = 5 * 3 ** 2;
+        var c = 5 ** 3 * 2;
+        var d = 5 ** +3;
+    }
+    expect: {
+        var a = 18;
+        var b = 45;
+        var c = 250;
+        var d = 125;
+    }
+}
+
+pow_with_right_side_evaluating_to_unary: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a = (4 - 7) ** foo;
+        var b = ++bar ** 3;
+        var c = --baz ** 2;
+    }
+    expect_exact: "var a=(-3)**foo;var b=++bar**3;var c=--baz**2;"
+}
+
+pow_with_number_constants: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a = 5 ** NaN;
+        /* NaN exponent results to NaN */
+        var b = 42 ** +0;
+        /* +0 exponent results to NaN */
+        var c = 42 ** -0;
+        /* -0 exponent results to NaN */
+        var d = NaN ** 1;
+        /* NaN with non-zero exponent is NaN */
+        var e = 2 ** Infinity;
+        /* abs(base) > 1 with Infinity as exponent is Infinity */
+        var f = 2 ** -Infinity;
+        /* abs(base) > 1 with -Infinity as exponent is +0 */
+        var g = (-7) ** (0.5);
+        var h = 2324334 ** 34343443;
+        var i = (-2324334) ** 34343443;
+        var j = 2 ** (-3);
+        var k = 2.0 ** -3;
+        var l = 2.0 ** (5 - 7);
+        var m = 3 ** -10;  // Result will be 0.000016935087808430286, which is too long
+    }
+    expect: {
+        var a = NaN;
+        var b = 1;
+        var c = 1;
+        var d = NaN;
+        var e = Infinity;
+        var f = 0;
+        var g = NaN;
+        var h = Infinity;
+        var i = -Infinity;
+        var j = .125;
+        var k = .125;
+        var l = .25;
+        var m = 3 ** -10;
+    }
+}
+
+unsafe_constant: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            true.a,
+            false.a,
+            null.a,
+            undefined.a
+        );
+    }
+    expect: {
+        console.log(
+            true.a,
+            false.a,
+            null.a,
+            (void 0).a
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_object: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            ({a:1}) + 1,
+            ({a:1}).a + 1,
+            ({a:1}).b + 1,
+            ({a:1}).a.b + 1
+        );
+    }
+    expect: {
+        console.log(
+            ({a:1}) + 1,
+            2,
+            ({a:1}).b + 1,
+            1..b + 1
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_object_nested: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            ({a:{b:1}}) + 1,
+            ({a:{b:1}}).a + 1,
+            ({a:{b:1}}).b + 1,
+            ({a:{b:1}}).a.b + 1
+        );
+    }
+    expect: {
+        console.log(
+            ({a:{b:1}}) + 1,
+            ({a:{b:1}}).a + 1,
+            ({a:{b:1}}).b + 1,
+            2
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_object_complex: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            ({a:{b:1},b:1}) + 1,
+            ({a:{b:1},b:1}).a + 1,
+            ({a:{b:1},b:1}).b + 1,
+            ({a:{b:1},b:1}).a.b + 1
+        );
+    }
+    expect: {
+        console.log(
+            ({a:{b:1},b:1}) + 1,
+            ({a:{b:1},b:1}).a + 1,
+            2,
+            2
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_object_repeated: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            ({a:{b:1},a:1}) + 1,
+            ({a:{b:1},a:1}).a + 1,
+            ({a:{b:1},a:1}).b + 1,
+            ({a:{b:1},a:1}).a.b + 1
+        );
+    }
+    expect: {
+        console.log(
+            ({a:{b:1},a:1}) + 1,
+            2,
+            ({a:{b:1},a:1}).b + 1,
+            1..b + 1
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_object_accessor: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+    }
+    input: {
+        function f() {
+            var a = {
+                get b() {},
+                set b() {}
+            };
+            return {a:a};
+        }
+    }
+    expect: {
+        function f() {
+            var a = {
+                get b() {},
+                set b() {}
+            };
+            return {a:a};
+        }
+    }
+}
+
+unsafe_function: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            ({a:{b:1},b:function(){}}) + 1,
+            ({a:{b:1},b:function(){}}).a + 1,
+            ({a:{b:1},b:function(){}}).b + 1,
+            ({a:{b:1},b:function(){}}).a.b + 1
+        );
+    }
+    expect: {
+        console.log(
+            ({a:{b:1},b:function(){}}) + 1,
+            ({a:{b:1},b:function(){}}).a + 1,
+            ({a:{b:1},b:function(){}}).b + 1,
+            ({a:{b:1},b:function(){}}).a.b + 1
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_integer_key: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            ({0:1}) + 1,
+            ({0:1})[0] + 1,
+            ({0:1})["0"] + 1,
+            ({0:1})[1] + 1,
+            ({0:1})[0][1] + 1,
+            ({0:1})[0]["1"] + 1
+        );
+    }
+    expect: {
+        console.log(
+            ({0:1}) + 1,
+            2,
+            2,
+            ({0:1})[1] + 1,
+            1[1] + 1,
+            1["1"] + 1
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_integer_key_complex: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            ({0:{1:1},1:1}) + 1,
+            ({0:{1:1},1:1})[0] + 1,
+            ({0:{1:1},1:1})["0"] + 1,
+            ({0:{1:1},1:1})[1] + 1,
+            ({0:{1:1},1:1})[0][1] + 1,
+            ({0:{1:1},1:1})[0]["1"] + 1
+        );
+    }
+    expect: {
+        console.log(
+            ({0:{1:1},1:1}) + 1,
+            "[object Object]1",
+            "[object Object]1",
+            2,
+            2,
+            2
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_float_key: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            ({2.72:1}) + 1,
+            ({2.72:1})[2.72] + 1,
+            ({2.72:1})["2.72"] + 1,
+            ({2.72:1})[3.14] + 1,
+            ({2.72:1})[2.72][3.14] + 1,
+            ({2.72:1})[2.72]["3.14"] + 1
+        );
+    }
+    expect: {
+        console.log(
+            ({2.72:1}) + 1,
+            2,
+            2,
+            ({2.72:1})[3.14] + 1,
+            1[3.14] + 1,
+            1["3.14"] + 1
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_float_key_complex: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            ({2.72:{3.14:1},3.14:1}) + 1,
+            ({2.72:{3.14:1},3.14:1})[2.72] + 1,
+            ({2.72:{3.14:1},3.14:1})["2.72"] + 1,
+            ({2.72:{3.14:1},3.14:1})[3.14] + 1,
+            ({2.72:{3.14:1},3.14:1})[2.72][3.14] + 1,
+            ({2.72:{3.14:1},3.14:1})[2.72]["3.14"] + 1
+        );
+    }
+    expect: {
+        console.log(
+            "[object Object]1",
+            "[object Object]1",
+            "[object Object]1",
+            2,
+            2,
+            2
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_array: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            [1, , 3][1],
+            [1, 2, 3, a] + 1,
+            [1, 2, 3, 4] + 1,
+            [1, 2, 3, a][0] + 1,
+            [1, 2, 3, 4][0] + 1,
+            [1, 2, 3, 4][6 - 5] + 1,
+            [1, , 3, 4][6 - 5] + 1,
+            [[1, 2], [3, 4]][0] + 1,
+            [[1, 2], [3, 4]][6 - 5][1] + 1,
+            [[1, 2], , [3, 4]][6 - 5][1] + 1
+        );
+    }
+    expect: {
+        console.log(
+            void 0,
+            [1, 2, 3, a] + 1,
+            "1,2,3,41",
+            [1, 2, 3, a][0] + 1,
+            2,
+            3,
+            NaN,
+            "1,21",
+            5,
+            (void 0)[1] + 1
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_string: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            "1234" + 1,
+            "1234"[0] + 1,
+            "1234"[6 - 5] + 1,
+            ("12" + "34")[0] + 1,
+            ("12" + "34")[6 - 5] + 1,
+            [1, 2, 3, 4].join("")[0] + 1
+        );
+    }
+    expect: {
+        console.log(
+            "12341",
+            "11",
+            "21",
+            "11",
+            "21",
+            "11"
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_array_bad_index: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            [1, 2, 3, 4].a + 1,
+            [1, 2, 3, 4]["a"] + 1,
+            [1, 2, 3, 4][3.14] + 1
+        );
+    }
+    expect: {
+        console.log(
+            [1, 2, 3, 4].a + 1,
+            [1, 2, 3, 4]["a"] + 1,
+            [1, 2, 3, 4][3.14] + 1
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_string_bad_index: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            "1234".a + 1,
+            "1234"["a"] + 1,
+            "1234"[3.14] + 1
+        );
+    }
+    expect: {
+        console.log(
+            "1234".a + 1,
+            "1234"["a"] + 1,
+            "1234"[3.14] + 1
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_prototype_function: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        var a = ({valueOf: 0}) < 1;
+        var b = ({toString: 0}) < 1;
+        var c = ({valueOf: 0}) + "";
+        var d = ({toString: 0}) + "";
+        var e = (({valueOf: 0}) + "")[2];
+        var f = (({toString: 0}) + "")[2];
+        var g = ({valueOf: 0}).valueOf();
+        var h = ({toString: 0}).toString();
+    }
+    expect: {
+        var a = ({valueOf: 0}) < 1;
+        var b = ({toString: 0}) < 1;
+        var c = ({valueOf: 0}) + "";
+        var d = ({toString: 0}) + "";
+        var e = (({valueOf: 0}) + "")[2];
+        var f = (({toString: 0}) + "")[2];
+        var g = ({valueOf: 0}).valueOf();
+        var h = "" + ({toString: 0});
+    }
+}
+
+call_args: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        const a = 1;
+        console.log(a);
+        +function(a) {
+            return a;
+        }(a);
+    }
+    expect: {
+        const a = 1;
+        console.log(1);
+        +(1, 1);
+    }
+    expect_stdout: true
+}
+
+call_args_drop_param: {
+    options = {
+        evaluate: true,
+        keep_fargs: false,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        const a = 1;
+        console.log(a);
+        +function(a) {
+            return a;
+        }(a, b);
+    }
+    expect: {
+        const a = 1;
+        console.log(1);
+        +(b, 1);
+    }
+    expect_stdout: true
+}
+
+in_boolean_context: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(
+            !42,
+            !"foo",
+            ![1, 2],
+            !/foo/,
+            !b(42),
+            !b("foo"),
+            !b([1, 2]),
+            !b(/foo/),
+            ![1, foo()],
+            ![1, foo(), 2]
+        );
+    }
+    expect: {
+        console.log(
+            !1,
+            !1,
+            !1,
+            !1,
+            !b(42),
+            !b("foo"),
+            !b([1, 2]),
+            !b(/foo/),
+            ![1, foo()],
+            (foo(), !1)
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_charAt: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            "1234" + 1,
+            "1234".charAt(0) + 1,
+            "1234".charAt(6 - 5) + 1,
+            ("12" + "34").charAt(0) + 1,
+            ("12" + "34").charAt(6 - 5) + 1,
+            [1, 2, 3, 4].join("").charAt(0) + 1
+        );
+    }
+    expect: {
+        console.log(
+            "12341",
+            "11",
+            "21",
+            "11",
+            "21",
+            "11"
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_charAt_bad_index: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            "1234".charAt() + 1,
+            "1234".charAt("a") + 1,
+            "1234".charAt(3.14) + 1
+        );
+    }
+    expect: {
+        console.log(
+            "11",
+            "11",
+            "41"
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_charAt_noop: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            s.charAt(0),
+            "string".charAt(x)
+        );
+    }
+    expect: {
+        console.log(
+            s.charAt(0),
+            "string".charAt(x)
+        );
+    }
+}

test/compress/expansions.js

@@ -0,0 +1,28 @@
+
+expand_arguments: {
+    input: {
+        func(a, ...rest);
+        func(...all);
+    }
+    expect_exact: "func(a,...rest);func(...all);"
+}
+
+expand_expression_arguments: {
+    input: {
+        f(...a.b);
+        f(...a.b());
+        f(...(a));
+        f(...(a.b));
+        f(...a[i]);
+    }
+    expect_exact: "f(...a.b);f(...a.b());f(...a);f(...a.b);f(...a[i]);"
+}
+
+expand_parameters: {
+    input: {
+        (function (a, ...b){});
+        (function (...args){});
+    }
+    expect_exact: "(function(a,...b){});(function(...args){});"
+}
+

test/compress/expression.js

@@ -0,0 +1,52 @@
+pow: {
+    input: {
+        var a = 2 ** 7;
+        var b = 3;
+        b **= 2;
+    }
+    expect: {
+        var a = 2 ** 7;
+        var b = 3;
+        b **= 2;
+    }
+}
+
+pow_with_number_constants: {
+    input: {
+        var a = 5 ** NaN;
+        var b = 42 ** +0;
+        var c = 42 ** -0;
+        var d = NaN ** 1;
+        var e = 2 ** Infinity;
+        var f = 2 ** -Infinity;
+    }
+    expect: {
+        var a = 5 ** NaN;
+        var b = 42 ** +0;
+        var c = 42 ** -0;
+        var d = NaN ** 1;
+        var e = 2 ** (1/0);
+        var f = 2 ** -(1/0);
+    }
+}
+
+pow_with_parentheses: {
+    input: {
+        var g = (-7) ** (0.5);
+        var h = 2324334 ** 34343443;
+        var i = (-2324334) ** 34343443;
+        var j = 2 ** (-3);
+        var k = 2.0 ** -3;
+        var l = 2.0 ** (5 - 7);
+    }
+    expect_exact: "var g=(-7)**.5;var h=2324334**34343443;var i=(-2324334)**34343443;var j=2**-3;var k=2**-3;var l=2**(5-7);"
+}
+
+pow_with_unary_between_brackets: {
+    input: {
+        var a = (-(+5)) ** 3;
+    }
+    expect: {
+        var a = (-+5)**3;
+    }
+}

test/compress/functions.js

@@ -0,0 +1,95 @@
+non_ascii_function_identifier_name: {
+    input: {
+        function fooλ(δλ) {}
+        function λ(δλ) {}
+        (function λ(δλ) {})()
+    }
+    expect_exact: "function fooλ(δλ){}function λ(δλ){}(function λ(δλ){})();"
+}
+
+iifes_returning_constants_keep_fargs_true: {
+    options = {
+        keep_fargs    : true,
+        side_effects  : true,
+        evaluate      : true,
+        unused        : true,
+        dead_code     : true,
+        conditionals  : true,
+        comparisons   : true,
+        booleans      : true,
+        if_return     : true,
+        join_vars     : true,
+        reduce_vars   : true,
+        cascade       : true,
+    }
+    input: {
+        (function(){ return -1.23; }());
+        console.log( function foo(){ return "okay"; }() );
+        console.log( function foo(x, y, z){ return 123; }() );
+        console.log( function(x, y, z){ return z; }() );
+        console.log( function(x, y, z){ if (x) return y; return z; }(1, 2, 3) );
+        console.log( function(x, y){ return x * y; }(2, 3) );
+        console.log( function(x, y){ return x * y; }(2, 3, a(), b()) );
+    }
+    expect: {
+        console.log("okay");
+        console.log(123);
+        console.log(void 0);
+        console.log(2);
+        console.log(6);
+        console.log((a(), b(), 6));
+    }
+    expect_stdout: true
+}
+
+iifes_returning_constants_keep_fargs_false: {
+    options = {
+        keep_fargs    : false,
+        side_effects  : true,
+        evaluate      : true,
+        unused        : true,
+        dead_code     : true,
+        conditionals  : true,
+        comparisons   : true,
+        booleans      : true,
+        if_return     : true,
+        join_vars     : true,
+        reduce_vars   : true,
+        cascade       : true,
+    }
+    input: {
+        (function(){ return -1.23; }());
+        console.log( function foo(){ return "okay"; }() );
+        console.log( function foo(x, y, z){ return 123; }() );
+        console.log( function(x, y, z){ return z; }() );
+        console.log( function(x, y, z){ if (x) return y; return z; }(1, 2, 3) );
+        console.log( function(x, y){ return x * y; }(2, 3) );
+        console.log( function(x, y){ return x * y; }(2, 3, a(), b()) );
+    }
+    expect: {
+        console.log("okay");
+        console.log(123);
+        console.log(void 0);
+        console.log(2);
+        console.log(6);
+        console.log((a(), b(), 6));
+    }
+    expect_stdout: true
+}
+
+issue_485_crashing_1530: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+    }
+    input: {
+        (function(a) {
+            if (true) return;
+            var b = 42;
+        })(this);
+    }
+    expect: {
+        this, void 0;
+    }
+}

test/compress/global_defs.js

@@ -0,0 +1,147 @@
+must_replace: {
+    options = {
+        global_defs: {
+            D: "foo bar",
+        }
+    }
+    input: {
+        console.log(D);
+    }
+    expect: {
+        console.log("foo bar");
+    }
+}
+
+keyword: {
+    options = {
+        global_defs: {
+            undefined: 0,
+            NaN: 1,
+            Infinity: 2,
+        },
+    }
+    input: {
+        console.log(undefined, NaN, Infinity);
+    }
+    expect: {
+        console.log(0, 1, 2);
+    }
+}
+
+object: {
+    options = {
+        evaluate: true,
+        global_defs: {
+            CONFIG: {
+                DEBUG: [ 0 ],
+                VALUE: 42,
+            },
+        },
+        unsafe: true,
+    }
+    input: {
+        function f(CONFIG) {
+            // CONFIG not global - do not replace
+            return CONFIG.VALUE;
+        }
+        function g() {
+            var CONFIG = { VALUE: 1 };
+            // CONFIG not global - do not replace
+            return CONFIG.VALUE;
+        }
+        function h() {
+            return CONFIG.VALUE;
+        }
+        if (CONFIG.DEBUG[0])
+            console.debug("foo");
+    }
+    expect: {
+        function f(CONFIG) {
+            return CONFIG.VALUE;
+        }
+        function g() {
+            var CONFIG = { VALUE: 1 };
+            return CONFIG.VALUE;
+        }
+        function h() {
+            return 42;
+        }
+        if (0)
+            console.debug("foo");
+    }
+}
+
+expanded: {
+    options = {
+        global_defs: {
+            "CONFIG.DEBUG": [ 0 ],
+            "CONFIG.VALUE": 42,
+        },
+    }
+    input: {
+        function f(CONFIG) {
+            // CONFIG not global - do not replace
+            return CONFIG.VALUE;
+        }
+        function g() {
+            var CONFIG = { VALUE: 1 };
+            // CONFIG not global - do not replace
+            return CONFIG.VALUE;
+        }
+        function h() {
+            return CONFIG.VALUE;
+        }
+        if (CONFIG.DEBUG[0])
+            console.debug("foo");
+    }
+    expect: {
+        function f(CONFIG) {
+            return CONFIG.VALUE;
+        }
+        function g() {
+            var CONFIG = { VALUE: 1 };
+            return CONFIG.VALUE;
+        }
+        function h() {
+            return 42;
+        }
+        if ([0][0])
+            console.debug("foo");
+    }
+}
+
+mixed: {
+    options = {
+        evaluate: true,
+        global_defs: {
+            "CONFIG.VALUE": 42,
+            "FOO.BAR": "moo",
+        },
+        properties: true,
+    }
+    input: {
+        const FOO = { BAR: 0 };
+        console.log(FOO.BAR);
+        console.log(++CONFIG.DEBUG);
+        console.log(++CONFIG.VALUE);
+        console.log(++CONFIG["VAL" + "UE"]);
+        console.log(++DEBUG[CONFIG.VALUE]);
+        CONFIG.VALUE.FOO = "bar";
+        console.log(CONFIG);
+    }
+    expect: {
+        const FOO = { BAR: 0 };
+        console.log("moo");
+        console.log(++CONFIG.DEBUG);
+        console.log(++CONFIG.VALUE);
+        console.log(++CONFIG.VALUE);
+        console.log(++DEBUG[42]);
+        CONFIG.VALUE.FOO = "bar";
+        console.log(CONFIG);
+    }
+    expect_warnings: [
+        'WARN: global_defs CONFIG.VALUE redefined [test/compress/global_defs.js:126,22]',
+        'WARN: global_defs CONFIG.VALUE redefined [test/compress/global_defs.js:127,22]',
+        'WARN: global_defs CONFIG.VALUE redefined [test/compress/global_defs.js:129,8]',
+    ]
+}

test/compress/harmony.js

@@ -0,0 +1,333 @@
+arrow_function_parens: {
+    input: {
+        something && (() => {});
+    }
+    expect_exact: "something&&(()=>{});"
+}
+arrow_function_parens_2: {
+    input: {
+        (() => null)();
+    }
+    expect_exact: "(()=>null)();"
+}
+
+typeof_arrow_functions: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var foo = typeof (x) => null;
+    }
+    expect_exact: "var foo=\"function\";"
+}
+
+classes: {
+    input: {
+        class SomeClass {
+            constructor() {
+            };
+            foo() {};
+        };
+        class NoSemi {
+            constructor(...args) {
+            }
+            foo() {}
+        };
+        class ChildClass extends SomeClass {};
+        var asExpression = class AsExpression {};
+        var nameless = class {};
+    }
+    expect_exact: "class SomeClass{constructor(){}foo(){}}class NoSemi{constructor(...args){}foo(){}}class ChildClass extends SomeClass{}var asExpression=class AsExpression{};var nameless=class{};"
+}
+
+class_statics: {
+    input: {
+        x = class {
+            static staticMethod() {}
+            static get foo() {}
+            static set bar() {}
+            static() { /* "static" can be a method name! */ }
+            get() { /* "get" can be a method name! */ }
+            set() { /* "set" can be a method name! */ }
+        }
+    }
+    expect_exact: "x=class{static staticMethod(){}static get foo(){}static set bar(){}static(){}get(){}set(){}};"
+}
+
+class_name_can_be_mangled: {
+    mangle = { };
+    input: {
+        function x() {
+            class Foo {
+            }
+            var class1 = Foo
+            var class2 = class Bar {}
+        }
+    }
+    expect: {
+        function x() {
+            class a { }
+            var n = a
+            var r = class a {}
+        }
+    }
+}
+
+class_name_can_be_preserved: {
+    mangle = {
+        keep_classnames: true
+    }
+    input: {
+        function x() {
+            (class Baz { });
+            class Foo {};
+        }
+    }
+    expect: {
+        function x() {
+            (class Baz { });
+            class Foo {};
+        }
+    }
+}
+
+classes_can_have_generators: {
+    input: {
+        class Foo {
+            *bar() {}
+            static *baz() {}
+        }
+    }
+    expect: {
+        class Foo {
+            *bar() {}
+            static *baz() {}
+        }
+    }
+}
+
+classes_can_have_computed_generators: {
+    input: {
+        class C4 {
+            *['constructor']() {}
+        }
+    }
+    expect: {
+        class C4 {
+            *['constructor']() {}
+        }
+    }
+}
+
+classes_can_have_computed_static: {
+    input: {
+        class C4 {
+            static ['constructor']() {}
+        }
+    }
+    expect: {
+        class C4 {
+            static ['constructor']() {}
+        }
+    }
+}
+
+class_methods_and_getters_with_keep_quoted_props_enabled: {
+    beautify = {
+        quote_style: 3,
+        keep_quoted_props: true,
+    }
+    input: {
+        class clss {
+            a() {}
+            "b"() {}
+            get c() { return "c"}
+            get "d"() { return "d"}
+            set e(a) { doSomething(a); }
+            set 'f'(a) { doSomething(b); }
+            static g() {}
+            static "h"() {}
+        }
+    }
+    expect_exact: 'class clss{a(){}"b"(){}get c(){return"c"}get"d"(){return"d"}set e(a){doSomething(a)}set\'f\'(a){doSomething(b)}static g(){}static"h"(){}}'
+}
+
+new_target: {
+    input: {
+        new.target;
+        new.target.name;
+    }
+    expect_exact: "new.target;new.target.name;"
+}
+
+number_literals: {
+    input: {
+        0b1001;
+        0B1001;
+        0o11;
+        0O11;
+    }
+
+    expect: {
+        9;
+        9;
+        9;
+        9;
+    }
+}
+
+import_statement: {
+    input: {
+        import "mod-name";
+        import Foo from "bar";
+        import { Bar, Baz } from 'lel';
+        import Bar, { Foo } from 'lel';
+        import { Bar as kex, Baz as food } from 'lel';
+    }
+    expect_exact: "import\"mod-name\";import Foo from\"bar\";import{Bar,Baz}from\"lel\";import Bar,{Foo}from\"lel\";import{Bar as kex,Baz as food}from\"lel\";"
+}
+
+export_statement: {
+    input: {
+        export default 1;
+        export var foo = 4;
+        export let foo = 6;
+        export const foo = 6;
+        export function foo() {};
+        export class foo { };
+    }
+    expect_exact: "export default 1;export var foo=4;export let foo=6;export const foo=6;export function foo(){};export class foo{};"
+}
+
+import_statement_mangling: {
+    mangle = { toplevel: true };
+    input: {
+        import Foo from "foo";
+        import Bar, {Food} from "lel";
+        import {What as Whatever} from "lel";
+        Foo();
+        Bar();
+        Food();
+        Whatever();
+    }
+    expect: {
+        import l from "foo";
+        import e, {Food as o} from "lel";
+        import {What as f} from "lel";
+        l();
+        e();
+        o();
+        f();
+    }
+}
+
+export_statement_mangling: {
+    mangle = { };
+    input: {
+        export var foo = 6;
+        export function bar() { }
+        export class Baz { }
+        bar(foo, Baz)
+    }
+    expect: {
+        export var foo = 6;
+        export function bar() { }
+        export class Baz { }
+        bar(foo, Baz)
+    }
+}
+
+// https://github.com/mishoo/UglifyJS2/issues/1021
+regression_for_of_const: {
+    input: {
+        for (const x of y) {}
+        for (const x in y) {}
+    }
+    expect: {
+        for (const x of y);for (const x in y);
+    }
+}
+
+// Fabio: My patches accidentally caused a crash whenever
+// there's an extraneous set of parens around an object.
+regression_cannot_destructure: {
+    input: {
+        var x = ({ x : 3 });
+        x(({ x: 3 }));
+    }
+    expect_exact: "var x={x:3};x({x:3});";
+}
+
+regression_cannot_use_of: {
+    input: {
+        function of() {
+        }
+        var of = "is a valid variable name";
+        of = { of: "is ok" };
+        x.of;
+        of: foo()
+    }
+    expect: {
+        function of(){}
+        var of="is a valid variable name";
+        of={of:"is ok"};
+        x.of;
+        foo();  /* Label statement missing? No prob. */
+    }
+}
+
+fat_arrow_as_param: {
+    input: {
+        foo(x => x);
+        foo(x => x, y => y);
+
+        foo(x => (x, x));
+        foo(x => (x, x), y => (y, y));
+    }
+    expect_exact: "foo(x=>x);foo(x=>x,y=>y);foo(x=>(x,x));foo(x=>(x,x),y=>(y,y));"
+}
+
+default_assign: {
+    options = {
+        keep_fargs: false,
+        unused: true,
+    }
+    input: {
+        function f(a, b = 3) {
+            console.log(a);
+        }
+    }
+    expect: {
+        function f(a) {
+            console.log(a);
+        }
+    }
+}
+
+expansion: {
+    options = {
+        keep_fargs: false,
+        unused: true,
+    }
+    input: {
+        function f(a, ...b) {
+            console.log(a);
+        }
+    }
+    expect: {
+        function f(a) {
+            console.log(a);
+        }
+    }
+}
+
+issue_1613: {
+  mangle = { toplevel: true };
+  input: {
+    const name = 1;
+    const foo = {
+      name
+    };
+  }
+  expect_exact: "const n=1;const c={name:n};"
+}

test/compress/hoist.js

@@ -0,0 +1,85 @@
+
+hoist_vars: {
+    options = {
+        hoist_vars: true
+    }
+    input: {
+        function a() {
+            bar();
+            var var1;
+            var var2;
+        }
+        function b(anArg) {
+            bar();
+            var var1;
+            var anArg;
+        }
+    }
+    expect: {
+        function a() {
+            var var1, var2;  // Vars go up and are joined
+            bar();
+        }
+        function b(anArg) {
+            var var1;
+            bar();
+            // But vars named like arguments go away!
+        }
+    }
+}
+
+hoist_funs: {
+    options = {
+        hoist_funs: true
+    }
+    input: {
+        function a() {
+            bar();
+            function foo() {}
+        }
+    }
+    expect: {
+        function a() {
+            function foo() {}  // Funs go up
+            bar();
+        }
+    }
+}
+
+hoist_no_destructurings: {
+    options = {
+        hoist_vars: true,
+        hoist_funs: true
+    }
+    input: {
+        function a([anArg]) {
+            bar();
+            var var1;
+            var anArg;  // Because anArg is already declared, this goes away!
+        }
+    }
+    expect: {
+        function a([anArg]) {
+            var var1;
+            bar();
+        }
+    }
+}
+
+dont_hoist_var_destructurings: {
+    options = {
+        hoist_vars: true,
+        hoist_funs: true
+    }
+    input: {
+        function x() {
+            // If foo is null or undefined, this should be an exception
+            var {x,y} = foo;
+        }
+    }
+    expect: {
+        function x() {
+            var {x,y} = foo;
+        }
+    }
+}

test/compress/hoist_vars.js

@@ -0,0 +1,90 @@
+statements: {
+    options = {
+        hoist_funs: false,
+        hoist_vars: true,
+    }
+    input: {
+        function f() {
+            var a = 1;
+            var b = 2;
+            var c = 3;
+            function g() {}
+            return g(a, b, c);
+        }
+    }
+    expect: {
+        function f() {
+            var a = 1, b = 2, c = 3;
+            function g() {}
+            return g(a, b, c);
+        }
+    }
+}
+
+statements_funs: {
+    options = {
+        hoist_funs: true,
+        hoist_vars: true,
+    }
+    input: {
+        function f() {
+            var a = 1;
+            var b = 2;
+            var c = 3;
+            function g() {}
+            return g(a, b, c);
+        }
+    }
+    expect: {
+        function f() {
+            function g() {}
+            var a = 1, b = 2, c = 3;
+            return g(a, b, c);
+        }
+    }
+}
+
+sequences: {
+    options = {
+        hoist_funs: false,
+        hoist_vars: true,
+    }
+    input: {
+        function f() {
+            var a = 1, b = 2;
+            function g() {}
+            var c = 3;
+            return g(a, b, c);
+        }
+    }
+    expect: {
+        function f() {
+            var c, a = 1, b = 2;
+            function g() {}
+            c = 3;
+            return g(a, b, c);
+        }
+    }
+}
+
+sequences_funs: {
+    options = {
+        hoist_funs: true,
+        hoist_vars: true,
+    }
+    input: {
+        function f() {
+            var a = 1, b = 2;
+            function g() {}
+            var c = 3;
+            return g(a, b, c);
+        }
+    }
+    expect: {
+        function f() {
+            function g() {}
+            var a = 1, b = 2, c = 3;
+            return g(a, b, c);
+        }
+    }
+}

test/compress/html_comments.js

@@ -0,0 +1,80 @@
+html_comment_in_expression: {
+    input: {
+        function f(a, b, x, y) { return a < !--b && x-- > y; }
+    }
+    expect_exact: "function f(a,b,x,y){return a< !--b&&x-- >y}";
+}
+
+html_comment_in_less_than: {
+    input: {
+        function f(a, b) { return a < !--b; }
+    }
+    expect_exact: "function f(a,b){return a< !--b}";
+}
+
+html_comment_in_left_shift: {
+    input: {
+        function f(a, b) { return a << !--b; }
+    }
+    expect_exact: "function f(a,b){return a<< !--b}";
+}
+
+html_comment_in_right_shift: {
+    input: {
+        function f(a, b) { return a-- >> b; }
+    }
+    expect_exact: "function f(a,b){return a-- >>b}";
+}
+
+html_comment_in_zero_fill_right_shift: {
+    input: {
+        function f(a, b) { return a-- >>> b; }
+    }
+    expect_exact: "function f(a,b){return a-- >>>b}";
+}
+
+html_comment_in_greater_than: {
+    input: {
+        function f(a, b) { return a-- > b; }
+    }
+    expect_exact: "function f(a,b){return a-- >b}";
+}
+
+html_comment_in_greater_than_or_equal: {
+    input: {
+        function f(a, b) { return a-- >= b; }
+    }
+    expect_exact: "function f(a,b){return a-- >=b}";
+}
+
+html_comment_in_right_shift_assign: {
+    input: {
+        // Note: illegal javascript
+        function f(a, b) { return a-- >>= b; }
+    }
+    expect_exact: "function f(a,b){return a-- >>=b}";
+}
+
+html_comment_in_zero_fill_right_shift_assign: {
+    input: {
+        // Note: illegal javascript
+        function f(a, b) { return a-- >>>= b; }
+    }
+    expect_exact: "function f(a,b){return a-- >>>=b}";
+}
+
+html_comment_in_string_literal: {
+    input: {
+        function f() { return "<!--HTML-->comment in<!--string literal-->"; }
+    }
+    expect_exact: 'function f(){return"\\x3c!--HTML--\\x3ecomment in\\x3c!--string literal--\\x3e"}';
+}
+
+html_comment_after_multiline_comment: {
+    input: {
+        var foo; /*
+*/-->   var bar;
+        var foobar;
+    }
+    expect_exact: "var foo;var foobar;"
+}

test/compress/if_return.js

@@ -0,0 +1,304 @@
+if_return_1: {
+    options = {
+        if_return    : true,
+        sequences    : true,
+        conditionals : true,
+        comparisons  : true,
+        evaluate     : true,
+        booleans     : true,
+        unused       : true,
+        side_effects : true,
+        dead_code    : true,
+    }
+    input: {
+        function f(x) {
+            if (x) {
+                return true;
+            }
+        }
+    }
+    expect: {
+        function f(x){if(x)return!0}
+    }
+}
+
+if_return_2: {
+    options = {
+        if_return    : true,
+        sequences    : true,
+        conditionals : true,
+        comparisons  : true,
+        evaluate     : true,
+        booleans     : true,
+        unused       : true,
+        side_effects : true,
+        dead_code    : true,
+    }
+    input: {
+        function f(x, y) {
+            if (x)
+                return 3;
+            if (y)
+                return c();
+        }
+    }
+    expect: {
+        function f(x,y){return x?3:y?c():void 0}
+    }
+}
+
+if_return_3: {
+    options = {
+        if_return    : true,
+        sequences    : true,
+        conditionals : true,
+        comparisons  : true,
+        evaluate     : true,
+        booleans     : true,
+        unused       : true,
+        side_effects : true,
+        dead_code    : true,
+    }
+    input: {
+        function f(x) {
+            a();
+            if (x) {
+                b();
+                return false;
+            }
+        }
+    }
+    expect: {
+        function f(x){if(a(),x)return b(),!1}
+    }
+}
+
+if_return_4: {
+    options = {
+        if_return    : true,
+        sequences    : true,
+        conditionals : true,
+        comparisons  : true,
+        evaluate     : true,
+        booleans     : true,
+        unused       : true,
+        side_effects : true,
+        dead_code    : true,
+    }
+    input: {
+        function f(x, y) {
+            a();
+            if (x) return 3;
+            b();
+            if (y) return c();
+        }
+    }
+    expect: {
+        function f(x,y){return a(),x?3:(b(),y?c():void 0)}
+    }
+}
+
+if_return_5: {
+    options = {
+        if_return    : true,
+        sequences    : true,
+        conditionals : true,
+        comparisons  : true,
+        evaluate     : true,
+        booleans     : true,
+        unused       : true,
+        side_effects : true,
+        dead_code    : true,
+    }
+    input: {
+        function f() {
+            if (x)
+                return;
+            return 7;
+            if (y)
+                return j;
+        }
+    }
+    expect: {
+        function f(){if(!x)return 7}
+    }
+}
+
+if_return_6: {
+    options = {
+        if_return    : true,
+        sequences    : true,
+        conditionals : true,
+        comparisons  : true,
+        evaluate     : true,
+        booleans     : true,
+        unused       : true,
+        side_effects : true,
+        dead_code    : true,
+    }
+    input: {
+        function f(x) {
+          return x ? true : void 0;
+          return y;
+        }
+    }
+    expect: {
+        // suboptimal
+        function f(x){return!!x||void 0}
+    }
+}
+
+if_return_7: {
+    options = {
+        if_return    : true,
+        sequences    : true,
+        conditionals : true,
+        comparisons  : true,
+        evaluate     : true,
+        booleans     : true,
+        unused       : true,
+        side_effects : true,
+        dead_code    : true,
+    }
+    input: {
+        function f(x) {
+            if (x) {
+                return true;
+            }
+            foo();
+            bar();
+        }
+    }
+    expect: {
+        function f(x){if(x)return!0;foo(),bar()}
+    }
+}
+
+if_return_8: {
+    options = {
+        if_return:     true,
+        sequences:     true,
+        conditionals:  true,
+        side_effects : true,
+    }
+    input: {
+        function f(e) {
+            if (2 == e) return foo();
+            if (3 == e) return bar();
+            if (4 == e) return baz();
+            fail(e);
+        }
+
+        function g(e) {
+            if (a(e)) return foo();
+            if (b(e)) return bar();
+            if (c(e)) return baz();
+            fail(e);
+        }
+
+        function h(e) {
+            if (a(e)) return foo();
+            else if (b(e)) return bar();
+            else if (c(e)) return baz();
+            else fail(e);
+        }
+
+        function i(e) {
+            if (a(e)) return foo();
+            else if (b(e)) return bar();
+            else if (c(e)) return baz();
+            fail(e);
+        }
+    }
+    expect: {
+        function f(e){return 2==e?foo():3==e?bar():4==e?baz():void fail(e)}
+        function g(e){return a(e)?foo():b(e)?bar():c(e)?baz():void fail(e)}
+        function h(e){return a(e)?foo():b(e)?bar():c(e)?baz():void fail(e)}
+        function i(e){return a(e)?foo():b(e)?bar():c(e)?baz():void fail(e)}
+    }
+}
+
+issue_1089: {
+    options = {
+        if_return    : true,
+        sequences    : true,
+        conditionals : true,
+        comparisons  : true,
+        evaluate     : true,
+        booleans     : true,
+        unused       : true,
+        side_effects : true,
+        dead_code    : true,
+    }
+    input: {
+        function x() {
+            var f = document.getElementById("fname");
+            if (f.files[0].size > 12345) {
+                alert("alert");
+                f.focus();
+                return false;
+            }
+        }
+    }
+    expect: {
+        function x() {
+            var f = document.getElementById("fname");
+            if (f.files[0].size > 12345)
+                return alert("alert"), f.focus(), !1;
+        }
+    }
+}
+
+issue_1437: {
+    options = {
+        if_return    : true,
+        sequences    : true,
+        conditionals : false
+    }
+    input: {
+        function x() {
+            if (a())
+                return b();
+            if (c())
+                return d();
+            else
+                e();
+            f();
+        }
+    }
+    expect: {
+        function x() {
+            if (a())
+                return b();
+            if (c())
+                return d();
+            else
+                e()
+            f();
+        }
+    }
+}
+
+issue_1437_conditionals: {
+    options = {
+        conditionals : true,
+        if_return    : true,
+        sequences    : true
+    }
+    input: {
+        function x() {
+            if (a())
+                return b();
+            if (c())
+                return d();
+            else
+                e();
+            f();
+        }
+    }
+    expect: {
+        function x() {
+            return a() ? b() : c() ? d() : (e(), f(), void 0);
+        }
+    }
+}

test/compress/issue-1001.js

@@ -0,0 +1,8 @@
+parenthesis_strings_in_parenthesis: {
+    input: {
+        var foo = ('(');
+        a(')');
+
+    }
+    expect_exact: 'var foo="(";a(")");'
+}

test/compress/issue-1034.js

@@ -0,0 +1,121 @@
+non_hoisted_function_after_return: {
+    options = {
+        hoist_funs: false, dead_code: true, conditionals: true, comparisons: true,
+        evaluate: true, booleans: true, loops: true, unused: true, keep_fargs: true,
+        if_return: true, join_vars: true, cascade: true, side_effects: true
+    }
+    input: {
+        function foo(x) {
+            if (x) {
+                return bar();
+                not_called1();
+            } else {
+                return baz();
+                not_called2();
+            }
+            function bar() { return 7; }
+            return not_reached;
+            function UnusedFunction() {}
+            function baz() { return 8; }
+        }
+    }
+    expect: {
+        function foo(x) {
+            return x ? bar() : baz();
+            function bar() { return 7 }
+            function baz() { return 8 }
+        }
+    }
+    expect_warnings: [
+        'WARN: Dropping unreachable code [test/compress/issue-1034.js:11,16]',
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:14,16]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:17,12]",
+        "WARN: Dropping unused function UnusedFunction [test/compress/issue-1034.js:18,21]"
+    ]
+}
+
+non_hoisted_function_after_return_2a: {
+    options = {
+        hoist_funs: false, dead_code: true, conditionals: true, comparisons: true,
+        evaluate: true, booleans: true, loops: true, unused: true, keep_fargs: true,
+        if_return: true, join_vars: true, cascade: true, side_effects: true,
+        collapse_vars: false, passes: 2
+    }
+    input: {
+        function foo(x) {
+            if (x) {
+                return bar(1);
+                var a = not_called(1);
+            } else {
+                return bar(2);
+                var b = not_called(2);
+            }
+            var c = bar(3);
+            function bar(x) { return 7 - x; }
+            function nope() {}
+            return b || c;
+        }
+    }
+    expect: {
+        function foo(x) {
+            return bar(x ? 1 : 2);
+            function bar(x) {
+                return 7 - x;
+            }
+        }
+    }
+    expect_warnings: [
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:48,16]",
+        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:48,16]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:51,16]",
+        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:51,16]",
+        "WARN: Dropping unused variable a [test/compress/issue-1034.js:48,20]",
+        "WARN: Dropping unused function nope [test/compress/issue-1034.js:55,21]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:53,12]",
+        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:53,12]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:56,12]",
+        "WARN: Dropping unused variable b [test/compress/issue-1034.js:51,20]",
+        "WARN: Dropping unused variable c [test/compress/issue-1034.js:53,16]"
+    ]
+}
+
+non_hoisted_function_after_return_2b: {
+    options = {
+        hoist_funs: false, dead_code: true, conditionals: true, comparisons: true,
+        evaluate: true, booleans: true, loops: true, unused: true, keep_fargs: true,
+        if_return: true, join_vars: true, cascade: true, side_effects: true,
+        collapse_vars: false
+    }
+    input: {
+        function foo(x) {
+            if (x) {
+                return bar(1);
+            } else {
+                return bar(2);
+                var b;
+            }
+            var c = bar(3);
+            function bar(x) {
+                return 7 - x;
+            }
+            return b || c;
+        }
+    }
+    expect: {
+        function foo(x) {
+            return bar(x ? 1 : 2);
+            function bar(x) { return 7 - x; }
+        }
+    }
+    expect_warnings: [
+        // duplicate warnings no longer emitted
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:95,16]",
+        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:95,16]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:97,12]",
+        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:97,12]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:101,12]",
+        "WARN: Dropping unused variable b [test/compress/issue-1034.js:95,20]",
+        "WARN: Dropping unused variable c [test/compress/issue-1034.js:97,16]"
+    ]
+}
+

test/compress/issue-1041.js

@@ -0,0 +1,41 @@
+const_declaration: {
+    options = {
+        evaluate: true
+    };
+
+    input: {
+        const goog = goog || {};
+    }
+    expect: {
+        const goog = goog || {};
+    }
+}
+
+const_pragma: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+    };
+
+    input: {
+        /** @const */ var goog = goog || {};
+    }
+    expect: {
+        var goog = goog || {};
+    }
+}
+
+// for completeness' sake
+not_const: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+    };
+
+    input: {
+        var goog = goog || {};
+    }
+    expect: {
+        var goog = goog || {};
+    }
+}

test/compress/issue-1043.js

@@ -0,0 +1,30 @@
+issue_1043: {
+    options = {
+        side_effects: true
+    };
+
+    input: {
+        function* range(start = 0, end = null, step = 1) {
+            if (end == null) {
+                end = start;
+                start = 0;
+            }
+
+            for (let i = start; i < end; i += step) {
+                yield i;
+            }
+        }
+    }
+
+    expect: {
+        function* range(start = 0, end = null, step = 1) {
+            if (null == end) {
+                end = start;
+                start = 0;
+            }
+
+            for (let i = start; i < end; i += step)
+                yield i;
+        }
+    }
+}

test/compress/issue-1044.js

@@ -0,0 +1,9 @@
+issue_1044: {
+    options = { evaluate: true, conditionals: true };
+    input: {
+        const mixed = Base ? class extends Base {} : class {}
+    }
+    expect: {
+        const mixed = Base ? class extends Base {} : class {}
+    }
+}

test/compress/issue-105.js

@@ -1,25 +0,0 @@
-typeof_eq_undefined: {
-    options = {
-        comparisons: true
-    };
-    input: { a = typeof b.c != "undefined" }
-    expect: { a = "undefined" != typeof b.c }
-}
-
-typeof_eq_undefined_unsafe: {
-    options = {
-        comparisons: true,
-        unsafe: true
-    };
-    input: { a = typeof b.c != "undefined" }
-    expect: { a = void 0 !== b.c }
-}
-
-typeof_eq_undefined_unsafe2: {
-    options = {
-        comparisons: true,
-        unsafe: true
-    };
-    input: { a = "undefined" != typeof b.c }
-    expect: { a = void 0 !== b.c }
-}

test/compress/issue-1052.js

@@ -0,0 +1,96 @@
+multiple_functions: {
+    options = { if_return: true, hoist_funs: false };
+    input: {
+        ( function() {
+            if ( !window ) {
+                return;
+            }
+
+            function f() {}
+            function g() {}
+        } )();
+    }
+    expect: {
+        ( function() {
+            function f() {}
+            function g() {}
+
+            // NOTE: other compression steps will reduce this
+            // down to just `window`.
+            if ( window );
+        } )();
+    }
+}
+
+single_function: {
+    options = { if_return: true, hoist_funs: false };
+    input: {
+        ( function() {
+            if ( !window ) {
+                return;
+            }
+
+            function f() {}
+        } )();
+    }
+    expect: {
+        ( function() {
+            function f() {}
+
+            if ( window );
+        } )();
+    }
+}
+
+deeply_nested: {
+    options = { if_return: true, hoist_funs: false };
+    input: {
+        ( function() {
+            if ( !window ) {
+                return;
+            }
+
+            function f() {}
+            function g() {}
+
+            if ( !document ) {
+                return;
+            }
+
+            function h() {}
+        } )();
+    }
+    expect: {
+        ( function() {
+            function f() {}
+            function g() {}
+
+            function h() {}
+
+            // NOTE: other compression steps will reduce this
+            // down to just `window`.
+            if ( window )
+                if (document);
+        } )();
+    }
+}
+
+not_hoisted_when_already_nested: {
+    options = { if_return: true, hoist_funs: false };
+    input: {
+        ( function() {
+            if ( !window ) {
+                return;
+            }
+
+            if ( foo ) function f() {}
+
+        } )();
+    }
+    expect: {
+        ( function() {
+            if ( window )
+                if ( foo ) function f() {}
+        } )();
+    }
+}

test/compress/issue-1105.js

@@ -0,0 +1,240 @@
+with_in_global_scope: {
+    options = {
+        unused: true
+    }
+    input: {
+        var o = 42;
+        with(o) {
+            var foo = 'something'
+        }
+        doSomething(o);
+    }
+    expect: {
+        var o=42;
+        with(o)
+            var foo = "something";
+        doSomething(o);
+    }
+}
+with_in_function_scope: {
+    options = {
+        unused: true
+    }
+    input: {
+        function foo() {
+            var o = 42;
+            with(o) {
+                var foo = "something"
+            }
+            doSomething(o);
+        }
+    }
+    expect: {
+        function foo() {
+            var o=42;
+            with(o)
+                var foo = "something";
+            doSomething(o)
+        }
+    }
+}
+compress_with_with_in_other_scope: {
+    options = {
+        unused: true
+    }
+    input: {
+        function foo() {
+            var o = 42;
+            with(o) {
+                var foo = "something"
+            }
+            doSomething(o);
+        }
+        function bar() {
+            var unused = 42;
+            return something();
+        }
+    }
+    expect: {
+        function foo() {
+            var o = 42;
+            with(o)
+                var foo = "something";
+            doSomething(o)
+        }
+        function bar() {
+            return something()
+        }
+    }
+}
+with_using_existing_variable_outside_scope: {
+    options = {
+        unused: true
+    }
+    input: {
+        function f() {
+            var o = {};
+            var unused = {}; // Doesn't get removed because upper scope uses with
+            function foo() {
+                with(o) {
+                    var foo = "something"
+                }
+                doSomething(o);
+            }
+            foo()
+        }
+    }
+    expect: {
+        function f() {
+            var o = {};
+            var unused = {};
+            function foo() {
+                with(o)
+                    var foo = "something";
+                doSomething(o)
+            }
+            foo()
+        }
+    }
+}
+check_drop_unused_in_peer_function: {
+    options = {
+        unused: true
+    }
+    input: {
+        function outer() {
+            var o = {};
+            var unused = {};     // should be kept
+            function foo() {     // should be kept
+                function not_in_use() {
+                    var nested_unused = "foo"; // should be dropped
+                    return 24;
+                }
+                var unused = {}; // should be kept
+                with (o) {
+                    var foo = "something";
+                }
+                doSomething(o);
+            }
+            function bar() {
+                var unused = {}; // should be dropped
+                doSomethingElse();
+            }
+            foo();
+            bar();
+        }
+    }
+    expect: {
+        function outer() {
+            var o = {};
+            var unused = {};     // should be kept
+            function foo() {     // should be kept
+                function not_in_use() {
+                    return 24;
+                }
+                var unused = {}; // should be kept
+                with (o)
+                    var foo = "something";
+                doSomething(o);
+            }
+            function bar() {
+                doSomethingElse();
+            }
+            foo();
+            bar();
+        }
+    }
+}
+
+Infinity_not_in_with_scope: {
+    options = {
+        unused: true
+    }
+    input: {
+        var o = { Infinity: 'oInfinity' };
+        var vInfinity = "Infinity";
+        vInfinity = Infinity;
+    }
+    expect: {
+        var o = { Infinity: 'oInfinity' }
+        var vInfinity = "Infinity"
+        vInfinity = 1/0
+    }
+}
+
+Infinity_in_with_scope: {
+    options = {
+        unused: true
+    }
+    input: {
+        var o = { Infinity: 'oInfinity' };
+        var vInfinity = "Infinity";
+        with (o) { vInfinity = Infinity; }
+    }
+    expect: {
+        var o = { Infinity: 'oInfinity' }
+        var vInfinity = "Infinity"
+        with (o) vInfinity = Infinity
+    }
+}
+
+assorted_Infinity_NaN_undefined_in_with_scope: {
+    options = {
+        unused:        true,
+        evaluate:      true,
+        dead_code:     true,
+        conditionals:  true,
+        comparisons:   true,
+        booleans:      true,
+        hoist_funs:    true,
+        keep_fargs:    true,
+        if_return:     true,
+        join_vars:     true,
+        cascade:       true,
+        side_effects:  true,
+        sequences:     false,
+    }
+    input: {
+        var o = {
+            undefined : 3,
+            NaN       : 4,
+            Infinity  : 5,
+        }
+        if (o) {
+            f(undefined, void 0);
+            f(NaN, 0/0);
+            f(Infinity, 1/0);
+            f(-Infinity, -(1/0));
+            f(2 + 7 + undefined, 2 + 7 + void 0);
+        }
+        with (o) {
+            f(undefined, void 0);
+            f(NaN, 0/0);
+            f(Infinity, 1/0);
+            f(-Infinity, -(1/0));
+            f(2 + 7 + undefined, 2 + 7 + void 0);
+        }
+    }
+    expect: {
+        var o = {
+            undefined : 3,
+            NaN       : 4,
+            Infinity  : 5
+        }
+        if (o) {
+            f(void 0, void 0);
+            f(NaN, NaN);
+            f(1/0, 1/0);
+            f(-(1/0), -(1/0));
+            f(NaN, NaN);
+        }
+        with (o) {
+            f(undefined, void 0);
+            f(NaN, 0/0);
+            f(Infinity, 1/0);
+            f(-Infinity, -(1/0));
+            f(9 + undefined, 9 + void 0);
+        }
+    }
+}
+

test/compress/issue-12.js

@@ -9,3 +9,50 @@ keep_name_of_setter: {
     input: { a = { set foo () {} } }
     expect: { a = { set foo () {} } }
 }
+
+setter_with_operator_keys: {
+    input: {
+        var tokenCodes  = {
+            get instanceof(){
+                return test0;
+            },
+            set instanceof(value){
+                test0 = value;
+            },
+            set typeof(value){
+                test1 = value;
+            },
+            get typeof(){
+                return test1;
+            },
+            set else(value){
+                test2 = value;
+            },
+            get else(){
+                return test2;
+            }
+        };
+    }
+    expect: {
+        var tokenCodes  = {
+            get instanceof(){
+                return test0;
+            },
+            set instanceof(value){
+                test0 = value;
+            },
+            set typeof(value){
+                test1 = value;
+            },
+            get typeof(){
+                return test1;
+            },
+            set else(value){
+                test2 = value;
+            },
+            get else(){
+                return test2;
+            }
+        };
+    }
+}

test/compress/issue-1202.js

@@ -0,0 +1,51 @@
+mangle_keep_fnames_false: {
+    options = {
+        keep_fnames : true,
+        keep_fargs  : true,
+    }
+    mangle = {
+        keep_fnames : false,
+    }
+    input: {
+        "use strict";
+        function total() {
+            return function n(a, b, c) {
+                return a + b + c;
+            };
+        }
+    }
+    expect: {
+        "use strict";
+        function total() {
+            return function t(n, r, u) {
+                return n + r + u;
+            };
+        }
+    }
+}
+
+mangle_keep_fnames_true: {
+    options = {
+        keep_fnames : true,
+        keep_fargs  : true,
+    }
+    mangle = {
+        keep_fnames : true,
+    }
+    input: {
+        "use strict";
+        function total() {
+            return function n(a, b, c) {
+                return a + b + c;
+            };
+        }
+    }
+    expect: {
+        "use strict";
+        function total() {
+            return function n(t, r, u) {
+                return t + r + u;
+            };
+        }
+    }
+}

test/compress/issue-1212.js

@@ -0,0 +1,76 @@
+issue_1212_debug_false: {
+    options = {
+        global_defs   : { DEBUG: false },
+        sequences     : true,
+        properties    : true,
+        dead_code     : true,
+        conditionals  : true,
+        comparisons   : true,
+        evaluate      : true,
+        booleans      : true,
+        loops         : true,
+        unused        : true,
+        hoist_funs    : true,
+        keep_fargs    : true,
+        if_return     : true,
+        join_vars     : true,
+        cascade       : true,
+        side_effects  : true,
+    }
+    input: {
+        class foo {
+            bar() {
+                if (DEBUG)
+                    console.log("DEV");
+                else
+                    console.log("PROD");
+            }
+        }
+        new foo().bar();
+    }
+    expect: {
+        class foo{
+            bar() { console.log("PROD") }
+        }
+        (new foo).bar();
+    }
+}
+
+issue_1212_debug_true: {
+    options = {
+        global_defs   : { DEBUG: true },
+        sequences     : true,
+        properties    : true,
+        dead_code     : true,
+        conditionals  : true,
+        comparisons   : true,
+        evaluate      : true,
+        booleans      : true,
+        loops         : true,
+        unused        : true,
+        hoist_funs    : true,
+        keep_fargs    : true,
+        if_return     : true,
+        join_vars     : true,
+        cascade       : true,
+        side_effects  : true,
+    }
+    input: {
+        class foo {
+            bar() {
+                if (DEBUG)
+                    console.log("DEV");
+                else
+                    console.log("PROD");
+            }
+        }
+        new foo().bar();
+    }
+    expect: {
+        class foo{
+            bar() { console.log("DEV") }
+        }
+        (new foo).bar();
+    }
+}
+

test/compress/issue-126.js

@@ -0,0 +1,24 @@
+concatenate_rhs_strings: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        foo(bar() + 123 + "Hello" + "World");
+        foo(bar() + (123 + "Hello") + "World");
+        foo((bar() + 123) + "Hello" + "World");
+        foo(bar() + 123 + "Hello" + "World" + ("Foo" + "Bar"));
+        foo("Foo" + "Bar" + bar() + 123 + "Hello" + "World" + ("Foo" + "Bar"));
+        foo("Hello" + bar() + 123 + "World");
+        foo(bar() + 'Foo' + (10 + parseInt('10')));
+    }
+    expect: {
+        foo(bar() + 123 + "HelloWorld");
+        foo(bar() + "123HelloWorld");
+        foo((bar() + 123) + "HelloWorld");
+        foo(bar() + 123 + "HelloWorldFooBar");
+        foo("FooBar" + bar() + "123HelloWorldFooBar");
+        foo("Hello" + bar() + "123World");
+        foo(bar() + 'Foo' + (10 + parseInt('10')));
+    }
+}

test/compress/issue-1261.js

@@ -0,0 +1,176 @@
+pure_function_calls: {
+    options = {
+        evaluate     : true,
+        conditionals : true,
+        comparisons  : true,
+        side_effects : true,
+        booleans     : true,
+        unused       : true,
+        if_return    : true,
+        join_vars    : true,
+        cascade      : true,
+        negate_iife  : true,
+    }
+    input: {
+        // pure top-level IIFE will be dropped
+        // @__PURE__ - comment
+        (function() {
+            console.log("iife0");
+        })();
+
+        // pure top-level IIFE assigned to unreferenced var will not be dropped
+        var iife1 = /*@__PURE__*/(function() {
+            console.log("iife1");
+            function iife1() {}
+            return iife1;
+        })();
+
+        (function(){
+            // pure IIFE in function scope assigned to unreferenced var will be dropped
+            var iife2 = /*#__PURE__*/(function() {
+                console.log("iife2");
+                function iife2() {}
+                return iife2;
+            })();
+        })();
+
+        // comment #__PURE__ comment
+        bar(), baz(), quux();
+        a.b(), /* @__PURE__ */ c.d.e(), f.g();
+    }
+    expect: {
+        var iife1 = function() {
+            console.log("iife1");
+            function iife1() {}
+            return iife1;
+        }();
+
+        baz(), quux();
+        a.b(), f.g();
+    }
+    expect_warnings: [
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:17,8]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:17,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:30,37]",
+        "WARN: Dropping unused variable iife2 [test/compress/issue-1261.js:30,16]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:28,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:38,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:39,31]",
+    ]
+}
+
+pure_function_calls_toplevel: {
+    options = {
+        evaluate     : true,
+        conditionals : true,
+        comparisons  : true,
+        side_effects : true,
+        booleans     : true,
+        unused       : true,
+        if_return    : true,
+        join_vars    : true,
+        cascade      : true,
+        negate_iife  : true,
+        toplevel     : true,
+    }
+    input: {
+        // pure top-level IIFE will be dropped
+        // @__PURE__ - comment
+        (function() {
+            console.log("iife0");
+        })();
+
+        // pure top-level IIFE assigned to unreferenced var will be dropped
+        var iife1 = /*@__PURE__*/(function() {
+            console.log("iife1");
+            function iife1() {}
+            return iife1;
+        })();
+
+        (function(){
+            // pure IIFE in function scope assigned to unreferenced var will be dropped
+            var iife2 = /*#__PURE__*/(function() {
+                console.log("iife2");
+                function iife2() {}
+                return iife2;
+            })();
+        })();
+
+        // comment #__PURE__ comment
+        bar(), baz(), quux();
+        a.b(), /* @__PURE__ */ c.d.e(), f.g();
+    }
+    expect: {
+        baz(), quux();
+        a.b(), f.g();
+    }
+    expect_warnings: [
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:79,8]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:79,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:92,37]",
+        "WARN: Dropping unused variable iife2 [test/compress/issue-1261.js:92,16]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:90,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:100,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:101,31]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:84,33]",
+        "WARN: Dropping unused variable iife1 [test/compress/issue-1261.js:84,12]",
+    ]
+}
+
+should_warn: {
+    options = {
+        booleans: true,
+        conditionals: true,
+        evaluate: true,
+        side_effects: true,
+    }
+    input: {
+        /* @__PURE__ */(function(){x})(), void/* @__PURE__ */(function(){y})();
+        /* @__PURE__ */(function(){x})() || true ? foo() : bar();
+        true || /* @__PURE__ */(function(){y})() ? foo() : bar();
+        /* @__PURE__ */(function(){x})() && false ? foo() : bar();
+        false && /* @__PURE__ */(function(){y})() ? foo() : bar();
+        /* @__PURE__ */(function(){x})() + "foo" ? bar() : baz();
+        "foo" + /* @__PURE__ */(function(){y})() ? bar() : baz();
+        /* @__PURE__ */(function(){x})() ? foo() : foo();
+        [/* @__PURE__ */(function(){x})()] ? foo() : bar();
+        !{ foo: /* @__PURE__ */(function(){x})() } ? bar() : baz();
+    }
+    expect: {
+        foo();
+        foo();
+        bar();
+        bar();
+        bar();
+        bar();
+        foo();
+        foo();
+        baz();
+    }
+    expect_warnings: [
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:128,61]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:128,23]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:128,23]",
+        "WARN: Boolean || always true [test/compress/issue-1261.js:129,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:129,23]",
+        "WARN: Condition always true [test/compress/issue-1261.js:129,23]",
+        "WARN: Boolean || always true [test/compress/issue-1261.js:130,8]",
+        "WARN: Condition always true [test/compress/issue-1261.js:130,8]",
+        "WARN: Boolean && always false [test/compress/issue-1261.js:131,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:131,23]",
+        "WARN: Condition always false [test/compress/issue-1261.js:131,23]",
+        "WARN: Boolean && always false [test/compress/issue-1261.js:132,8]",
+        "WARN: Condition always false [test/compress/issue-1261.js:132,8]",
+        "WARN: + in boolean context always true [test/compress/issue-1261.js:133,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:133,23]",
+        "WARN: Condition always true [test/compress/issue-1261.js:133,23]",
+        "WARN: + in boolean context always true [test/compress/issue-1261.js:134,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:134,31]",
+        "WARN: Condition always true [test/compress/issue-1261.js:134,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:135,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:136,24]",
+        "WARN: Condition always true [test/compress/issue-1261.js:136,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:137,31]",
+        "WARN: Condition always false [test/compress/issue-1261.js:137,8]",
+    ]
+}

test/compress/issue-1275.js

@@ -0,0 +1,50 @@
+string_plus_optimization: {
+    options = {
+        side_effects  : true,
+        evaluate      : true,
+        conditionals  : true,
+        comparisons   : true,
+        dead_code     : true,
+        booleans      : true,
+        unused        : true,
+        if_return     : true,
+        join_vars     : true,
+        cascade       : true,
+        hoist_funs    : true,
+    };
+    input: {
+        function foo(anything) {
+            function throwing_function() {
+                throw "nope";
+            }
+            try {
+                console.log('0' + throwing_function() ? "yes" : "no");
+            } catch (ex) {
+                console.log(ex);
+            }
+            console.log('0' + anything ? "yes" : "no");
+            console.log(anything + '0' ? "Yes" : "No");
+            console.log('' + anything);
+            console.log(anything + '');
+        }
+        foo();
+    }
+    expect: {
+        function foo(anything) {
+            function throwing_function() {
+                throw "nope";
+            }
+            try {
+                console.log((throwing_function(), "yes"));
+            } catch (ex) {
+                console.log(ex);
+            }
+            console.log("yes");
+            console.log("Yes");
+            console.log('' + anything);
+            console.log(anything + '');
+        }
+        foo();
+    }
+    expect_stdout: true
+}

test/compress/issue-1321.js

@@ -0,0 +1,57 @@
+issue_1321_no_debug: {
+    mangle_props = {
+        ignore_quoted: true
+    }
+    input: {
+        var x = {};
+        x.foo = 1;
+        x["a"] = 2 * x.foo;
+        console.log(x.foo, x["a"]);
+    }
+    expect: {
+        var x = {};
+        x.b = 1;
+        x["a"] = 2 * x.b;
+        console.log(x.b, x["a"]);
+    }
+    expect_stdout: true
+}
+
+issue_1321_debug: {
+    mangle_props = {
+        ignore_quoted: true,
+        debug: ""
+    }
+    input: {
+        var x = {};
+        x.foo = 1;
+        x["_$foo$_"] = 2 * x.foo;
+        console.log(x.foo, x["_$foo$_"]);
+    }
+    expect: {
+        var x = {};
+        x.a = 1;
+        x["_$foo$_"] = 2 * x.a;
+        console.log(x.a, x["_$foo$_"]);
+    }
+    expect_stdout: true
+}
+
+issue_1321_with_quoted: {
+    mangle_props = {
+        ignore_quoted: false
+    }
+    input: {
+        var x = {};
+        x.foo = 1;
+        x["a"] = 2 * x.foo;
+        console.log(x.foo, x["a"]);
+    }
+    expect: {
+        var x = {};
+        x.a = 1;
+        x["b"] = 2 * x.a;
+        console.log(x.a, x["b"]);
+    }
+    expect_stdout: true
+}

test/compress/issue-1431.js

@@ -0,0 +1,151 @@
+level_zero: {
+    options = {
+        keep_fnames: true
+    }
+    mangle = {
+        keep_fnames: true
+    }
+    input: {
+        function f(x) {
+            function n(a) {
+                return a * a;
+            }
+            return function() {
+                return x;
+            };
+        }
+    }
+    expect: {
+        function f(r) {
+            function n(n) {
+                return n * n;
+            }
+            return function() {
+                return r;
+            };
+        }
+    }
+}
+
+level_one: {
+    options = {
+        keep_fnames: true
+    }
+    mangle = {
+        keep_fnames: true
+    }
+    input: {
+        function f(x) {
+            return function() {
+                function n(a) {
+                    return a * a;
+                }
+                return x(n);
+            };
+        }
+    }
+    expect: {
+        function f(r) {
+            return function() {
+                function n(n) {
+                    return n * n;
+                }
+                return r(n);
+            };
+        }
+    }
+}
+
+level_two: {
+    options = {
+        keep_fnames: true
+    }
+    mangle = {
+        keep_fnames: true
+    }
+    input: {
+        function f(x) {
+            return function() {
+                function r(a) {
+                    return a * a;
+                }
+                return function() {
+                    function n(a) {
+                        return a * a;
+                    }
+                    return x(n);
+                };
+            };
+        }
+    }
+    expect: {
+        function f(t) {
+            return function() {
+                function r(n) {
+                    return n * n;
+                }
+                return function() {
+                    function n(n) {
+                        return n * n;
+                    }
+                    return t(n);
+                };
+            };
+        }
+    }
+}
+
+level_three: {
+    options = {
+        keep_fnames: true
+    }
+    mangle = {
+        keep_fnames: true
+    }
+    input: {
+        function f(x) {
+            return function() {
+                function r(a) {
+                    return a * a;
+                }
+                return [
+                    function() {
+                        function t(a) {
+                            return a * a;
+                        }
+                        return t;
+                    },
+                    function() {
+                        function n(a) {
+                            return a * a;
+                        }
+                        return x(n);
+                    }
+                ];
+            };
+        }
+    }
+    expect: {
+        function f(t) {
+            return function() {
+                function r(n) {
+                    return n * n;
+                }
+                return [
+                    function() {
+                        function t(n) {
+                            return n * n;
+                        }
+                        return t;
+                    },
+                    function() {
+                        function n(n) {
+                            return n * n;
+                        }
+                        return t(n);
+                    }
+                ];
+            };
+        }
+    }
+}

test/compress/issue-1443.js

@@ -0,0 +1,61 @@
+// tests assume that variable `undefined` not redefined and has `void 0` as value
+
+unsafe_undefined: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        unsafe: true
+    }
+    mangle = {}
+    input: {
+        function f(undefined) {
+            return function() {
+                if (a)
+                    return b;
+                if (c)
+                    return d;
+            };
+        }
+    }
+    expect: {
+        function f(n) {
+            return function() {
+                return a ? b : c ? d : n;
+            };
+        }
+    }
+}
+
+keep_fnames: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        unsafe: true
+    }
+    mangle = {
+        keep_fnames: true
+    }
+    input: {
+        function f(undefined) {
+            return function() {
+                function n(a) {
+                    return a * a;
+                }
+                if (a)
+                    return b;
+                if (c)
+                    return d;
+            };
+        }
+    }
+    expect: {
+        function f(r) {
+            return function() {
+                function n(n) {
+                    return n * n;
+                }
+                return a ? b : c ? d : r;
+            };
+        }
+    }
+}

test/compress/issue-1446.js

@@ -0,0 +1,71 @@
+typeof_eq_undefined: {
+    options = {
+        comparisons: true
+    }
+    input: {
+        var a = typeof b != "undefined";
+        b = typeof a != "undefined";
+        var c = typeof d.e !== "undefined";
+        var f = "undefined" === typeof g;
+        g = "undefined" === typeof f;
+        var h = "undefined" == typeof i.j;
+    }
+    expect: {
+        var a = "undefined" != typeof b;
+        b = void 0 !== a;
+        var c = void 0 !== d.e;
+        var f = "undefined" == typeof g;
+        g = void 0 === f;
+        var h = void 0 === i.j;
+    }
+}
+
+typeof_eq_undefined_ie8: {
+    options = {
+        comparisons: true,
+        screw_ie8: false
+    }
+    input: {
+        var a = typeof b != "undefined";
+        b = typeof a != "undefined";
+        var c = typeof d.e !== "undefined";
+        var f = "undefined" === typeof g;
+        g = "undefined" === typeof f;
+        var h = "undefined" == typeof i.j;
+    }
+    expect: {
+        var a = "undefined" != typeof b;
+        b = void 0 !== a;
+        var c = "undefined" != typeof d.e;
+        var f = "undefined" == typeof g;
+        g = void 0 === f;
+        var h = "undefined" == typeof i.j;
+    }
+}
+
+undefined_redefined: {
+    options = {
+        comparisons: true
+    }
+    input: {
+        function f(undefined) {
+            var n = 1;
+            return typeof n == "undefined";
+        }
+    }
+    expect_exact: "function f(undefined){var n=1;return void 0===n}"
+}
+
+undefined_redefined_mangle: {
+    options = {
+        comparisons: true
+    }
+    mangle = {}
+    input: {
+        function f(undefined) {
+            var n = 1;
+            return typeof n == "undefined";
+        }
+    }
+    expect_exact: "function f(n){var r=1;return void 0===r}"
+}

test/compress/issue-1447.js

@@ -0,0 +1,46 @@
+else_with_empty_block: {
+    options = {}
+    input: {
+        if (x)
+            yes();
+        else {
+        }
+    }
+    expect_exact: "if(x)yes();"
+}
+
+else_with_empty_statement: {
+    options = {}
+    input: {
+        if (x)
+            yes();
+        else
+            ;
+    }
+    expect_exact: "if(x)yes();"
+}
+
+conditional_false_stray_else_in_loop: {
+    options = {
+        evaluate     : true,
+        comparisons  : true,
+        booleans     : true,
+        unused       : true,
+        loops        : true,
+        side_effects : true,
+        dead_code    : true,
+        hoist_vars   : true,
+        join_vars    : true,
+        if_return    : true,
+        cascade      : true,
+        conditionals : false,
+    }
+    input: {
+        for (var i = 1; i <= 4; ++i) {
+            if (i <= 2) continue;
+            console.log(i);
+        }
+    }
+    expect_exact: "for(var i=1;i<=4;++i)if(!(i<=2))console.log(i);"
+    expect_stdout: true
+}

test/compress/issue-1466.js

@@ -0,0 +1,291 @@
+same_variable_in_multiple_for_loop: {
+    options = {
+        hoist_funs: true,
+        dead_code: true,
+        conditionals: true,
+        comparisons: true,
+        evaluate: true,
+        booleans: true,
+        loops: true,
+        unused: true,
+        keep_fargs: true,
+        if_return: true,
+        join_vars: true,
+        cascade: true,
+        side_effects: true,
+        collapse_vars: true,
+    }
+    mangle = {}
+    input: {
+        for (let i = 0; i < 3; i++) {
+            let a = 100;
+            console.log(i, a);
+            for (let i = 0; i < 2; i++) {
+                console.log(i, a);
+                let c = 2;
+                console.log(c);
+            }
+        }
+    }
+    expect: {
+        for (let o = 0; o < 3; o++) {
+            let l = 100;
+            console.log(o, l);
+            for (let o = 0; o < 2; o++) {
+                console.log(o, l);
+                let c = 2;
+                console.log(c);
+            }
+        }
+    }
+    expect_stdout: true
+}
+
+same_variable_in_multiple_forOf: {
+    options = {
+        hoist_funs: true,
+        dead_code: true,
+        conditionals: true,
+        comparisons: true,
+        evaluate: true,
+        booleans: true,
+        loops: true,
+        unused: true,
+        keep_fargs: true,
+        if_return: true,
+        join_vars: true,
+        cascade: true,
+        side_effects: true,
+        collapse_vars: true,
+    }
+    mangle = {}
+    input: {
+        var test = [ "a", "b", "c" ];
+        for (let tmp of test) {
+            console.log(tmp);
+            let dd;
+            dd = [ "e", "f", "g" ];
+            for (let tmp of dd) {
+                console.log(tmp);
+            }
+        }
+    }
+    expect: {
+        var test = [ "a", "b", "c" ];
+        for (let o of test) {
+            console.log(o);
+            let e;
+            e = [ "e", "f", "g" ];
+            for (let o of e)
+                console.log(o);
+        }
+    }
+    expect_stdout: true
+}
+
+same_variable_in_multiple_forIn: {
+    options = {
+        hoist_funs: true,
+        dead_code: true,
+        conditionals: true,
+        comparisons: true,
+        evaluate: true,
+        booleans: true,
+        loops: true,
+        unused: false,
+        keep_fargs: true,
+        if_return: true,
+        join_vars: true,
+        cascade: true,
+        side_effects: true,
+        collapse_vars: true,
+    }
+    mangle = {}
+    input: {
+        var test = [ "a", "b", "c" ];
+        for (let tmp in test) {
+            console.log(tmp);
+            let dd;
+            dd = [ "e", "f", "g" ];
+            for (let tmp in test) {
+                console.log(tmp);
+            }
+        }
+    }
+    expect: {
+        var test = [ "a", "b", "c" ];
+        for (let o in test) {
+            console.log(o);
+            let e;
+            e = [ "e", "f", "g" ];
+            for (let o in test)
+                console.log(o);
+        }
+    }
+    expect_stdout: true
+}
+
+different_variable_in_multiple_for_loop: {
+    options = {
+        hoist_funs: true,
+        dead_code: true,
+        conditionals: true,
+        comparisons: true,
+        evaluate: true,
+        booleans: true,
+        loops: true,
+        unused: true,
+        keep_fargs: true,
+        if_return: true,
+        join_vars: true,
+        cascade: true,
+        side_effects: true,
+        collapse_vars: true,
+    }
+    mangle = {}
+    input: {
+        for (let i = 0; i < 3; i++) {
+            let a = 100;
+            console.log(i, a);
+            for (let j = 0; j < 2; j++) {
+                console.log(j, a);
+                let c = 2;
+                console.log(c);
+            }
+        }
+    }
+    expect: {
+        for (let o = 0; o < 3; o++) {
+            let l = 100;
+            console.log(o, l);
+            for (let o = 0; o < 2; o++) {
+                console.log(o, l);
+                let c = 2;
+                console.log(c);
+            }
+        }
+    }
+    expect_stdout: true
+}
+
+different_variable_in_multiple_forOf: {
+    options = {
+        hoist_funs: true,
+        dead_code: true,
+        conditionals: true,
+        comparisons: true,
+        evaluate: true,
+        booleans: true,
+        loops: true,
+        unused: true,
+        keep_fargs: true,
+        if_return: true,
+        join_vars: true,
+        cascade: true,
+        side_effects: true,
+        collapse_vars: true,
+    }
+    mangle = {}
+    input: {
+        var test = [ "a", "b", "c" ];
+        for (let tmp of test) {
+            console.log(tmp);
+            let dd;
+            dd = [ "e", "f", "g" ];
+            for (let t of dd) {
+                console.log(t);
+            }
+        }
+    }
+    expect: {
+        var test = [ "a", "b", "c" ];
+        for (let o of test) {
+            console.log(o);
+            let e;
+            e = [ "e", "f", "g" ];
+            for (let o of e)
+                console.log(o);
+        }
+    }
+    expect_stdout: true
+}
+
+different_variable_in_multiple_forIn: {
+    options = {
+        hoist_funs: true,
+        dead_code: true,
+        conditionals: true,
+        comparisons: true,
+        evaluate: true,
+        booleans: true,
+        loops: true,
+        unused: false,
+        keep_fargs: true,
+        if_return: true,
+        join_vars: true,
+        cascade: true,
+        side_effects: true,
+        collapse_vars: true,
+    }
+    mangle = {}
+    input: {
+        var test = [ "a", "b", "c" ];
+        for (let tmp in test) {
+            console.log(tmp);
+            let dd;
+            dd = [ "e", "f", "g" ];
+            for (let t in test) {
+                console.log(t);
+            }
+        }
+    }
+    expect: {
+        var test = [ "a", "b", "c" ];
+        for (let o in test) {
+            console.log(o);
+            let e;
+            e = [ "e", "f", "g" ];
+            for (let o in test)
+                console.log(o);
+        }
+    }
+    expect_stdout: true
+}
+
+more_variable_in_multiple_for: {
+    options = {
+        hoist_funs: true,
+        dead_code: true,
+        conditionals: true,
+        comparisons: true,
+        evaluate: true,
+        booleans: true,
+        loops: true,
+        unused: false,
+        keep_fargs: true,
+        if_return: true,
+        join_vars: true,
+        cascade: true,
+        side_effects: true,
+        collapse_vars: true,
+    }
+    mangle = {}
+    input: {
+        for (let a = 9, i = 0; i < 20; i += a) {
+            let b = a++ + i;
+            console.log(a, b, i);
+            for (let k = b, m = b*b, i = 0; i < 10; i++) {
+                console.log(a, b, m, k, i);
+            }
+        }
+    }
+    expect: {
+        for (let o = 9, l = 0; l < 20; l += o) {
+            let c = o++ + l;
+            console.log(o, c, l);
+            for (let l = c, e = c * c, f = 0; f < 10; f++)
+                console.log(o, c, e, l, f);
+        }
+    }
+    expect_stdout: true
+}

test/compress/issue-1569.js

@@ -0,0 +1,19 @@
+inner_reference: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        !function f(a) {
+            return a && f(a - 1) + a;
+        }(42);
+        !function g(a) {
+            return a;
+        }(42);
+    }
+    expect: {
+        !function f(a) {
+            return a && f(a - 1) + a;
+        }(42);
+        !void 0;
+    }
+}

test/compress/issue-1588.js

@@ -0,0 +1,99 @@
+screw_ie8: {
+    options = {
+        screw_ie8: true,
+    }
+    mangle = {
+        screw_ie8: true,
+    }
+    input: {
+        try { throw "foo"; } catch (x) { console.log(x); }
+    }
+    expect_exact: 'try{throw"foo"}catch(o){console.log(o)}'
+    expect_stdout: [
+        "foo"
+    ]
+}
+
+support_ie8: {
+    options = {
+        screw_ie8: false,
+    }
+    mangle = {
+        screw_ie8: false,
+    }
+    input: {
+        try { throw "foo"; } catch (x) { console.log(x); }
+    }
+    expect_exact: 'try{throw"foo"}catch(x){console.log(x)}'
+    expect_stdout: "foo"
+}
+
+safe_undefined: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        unsafe: false,
+    }
+    mangle = {}
+    input: {
+        var a, c;
+        console.log(function(undefined) {
+            return function() {
+                if (a)
+                    return b;
+                if (c)
+                    return d;
+            };
+        }(1)());
+    }
+    expect: {
+        var a, c;
+        console.log(function(n) {
+            return function() {
+                return a ? b : c ? d : void 0;
+            };
+        }(1)());
+    }
+    expect_stdout: true
+}
+
+unsafe_undefined: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        unsafe: true,
+    }
+    mangle = {}
+    input: {
+        var a, c;
+        console.log(function(undefined) {
+            return function() {
+                if (a)
+                    return b;
+                if (c)
+                    return d;
+            };
+        }()());
+    }
+    expect: {
+        var a, c;
+        console.log(function(n) {
+            return function() {
+                return a ? b : c ? d : n;
+            };
+        }()());
+    }
+    expect_stdout: true
+}
+
+runtime_error: {
+    input: {
+        const a = 1;
+        console.log(a++);
+    }
+    expect: {
+        const a = 1;
+        console.log(a++);
+    }
+    expect_stdout: true
+}

test/compress/issue-1609.js

@@ -0,0 +1,56 @@
+chained_evaluation_1: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var a = 1;
+            (function() {
+                var b = a, c;
+                c = f(b);
+                c.bar = b;
+            })();
+        })();
+    }
+    expect: {
+        (function() {
+            (function() {
+                var c;
+                c = f(1);
+                c.bar = 1;
+            })();
+        })();
+    }
+}
+
+chained_evaluation_2: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var a = "long piece of string";
+            (function() {
+                var b = a, c;
+                c = f(b);
+                c.bar = b;
+            })();
+        })();
+    }
+    expect: {
+        (function() {
+            var a = "long piece of string";
+            (function() {
+                var c;
+                c = f(a);
+                c.bar = a;
+            })();
+        })();
+    }
+}

test/compress/issue-203.js

@@ -0,0 +1,34 @@
+
+compress_new_function: {
+    options = {
+        unsafe: true
+    }
+    input: {
+        new Function("aa, bb", 'return aa;');
+    }
+    expect: {
+        Function("a", "b", "return a");
+    }
+}
+
+compress_new_function_with_destruct: {
+    options = {
+        unsafe: true,
+        ecma: 6
+    }
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        new Function("aa, [bb]", 'return aa;');
+        new Function("aa, {bb}", 'return aa;');
+        new Function("[[aa]], [{bb}]", 'return aa;');
+    }
+    expect: {
+        Function("a", "[b]", "return a");
+        Function("a", "{bb}", "return a");
+        Function("[[a]]", "[{bb}]", 'return a');
+    }
+}
+
+

test/compress/issue-208.js

@@ -0,0 +1,70 @@
+do_not_update_lhs: {
+    options = {
+        global_defs: { DEBUG: 0 }
+    }
+    input: {
+        DEBUG++;
+        DEBUG += 1;
+        DEBUG = 1;
+    }
+    expect: {
+        DEBUG++;
+        DEBUG += 1;
+        DEBUG = 1;
+    }
+}
+
+do_update_rhs: {
+    options = {
+        global_defs: { DEBUG: 0 }
+    }
+    input: {
+        MY_DEBUG = DEBUG;
+        MY_DEBUG += DEBUG;
+    }
+    expect: {
+        MY_DEBUG = 0;
+        MY_DEBUG += 0;
+    }
+}
+
+mixed: {
+    options = {
+        evaluate: true,
+        global_defs: {
+            DEBUG: 0,
+            ENV: 1,
+            FOO: 2,
+        }
+    }
+    input: {
+        const ENV = 3;
+        var FOO = 4;
+        f(ENV * 10);
+        --FOO;
+        DEBUG = 1;
+        DEBUG++;
+        DEBUG += 1;
+        f(DEBUG);
+        x = DEBUG;
+    }
+    expect: {
+        const ENV = 3;
+        var FOO = 4;
+        f(10);
+        --FOO;
+        DEBUG = 1;
+        DEBUG++;
+        DEBUG += 1;
+        f(0);
+        x = 0;
+    }
+    expect_warnings: [
+        'WARN: global_defs ENV redefined [test/compress/issue-208.js:41,14]',
+        'WARN: global_defs FOO redefined [test/compress/issue-208.js:42,12]',
+        'WARN: global_defs FOO redefined [test/compress/issue-208.js:44,10]',
+        'WARN: global_defs DEBUG redefined [test/compress/issue-208.js:45,8]',
+        'WARN: global_defs DEBUG redefined [test/compress/issue-208.js:46,8]',
+        'WARN: global_defs DEBUG redefined [test/compress/issue-208.js:47,8]',
+    ]
+}

test/compress/issue-267.js

@@ -0,0 +1,11 @@
+issue_267: {
+    options = { comparisons: true };
+    input: {
+        x = a % b / b * c * 2;
+        x = a % b * 2
+    }
+    expect: {
+        x = a % b / b * c * 2;
+        x = a % b * 2;
+    }
+}

test/compress/issue-269.js

@@ -0,0 +1,66 @@
+issue_269_1: {
+	options = {unsafe: true};
+	input: {
+		f(
+			String(x),
+			Number(x),
+			Boolean(x),
+
+			String(),
+			Number(),
+			Boolean()
+		);
+	}
+	expect: {
+		f(
+			x + '', +x, !!x,
+			'', 0, false
+		);
+	}
+}
+
+issue_269_dangers: {
+	options = {unsafe: true};
+	input: {
+		f(
+			String(x, x),
+			Number(x, x),
+			Boolean(x, x)
+		);
+	}
+	expect: {
+		f(String(x, x), Number(x, x), Boolean(x, x));
+	}
+}
+
+issue_269_in_scope: {
+	options = {unsafe: true};
+	input: {
+		var String, Number, Boolean;
+		f(
+			String(x),
+			Number(x, x),
+			Boolean(x)
+		);
+	}
+	expect: {
+		var String, Number, Boolean;
+		f(String(x), Number(x, x), Boolean(x));
+	}
+}
+
+strings_concat: {
+	options = {unsafe: true};
+	input: {
+		f(
+			String(x + 'str'),
+			String('str' + x)
+		);
+	}
+	expect: {
+		f(
+			x + 'str',
+			'str' + x
+		);
+	}
+}

test/compress/issue-368.js

@@ -0,0 +1,55 @@
+collapse: {
+    options = {
+        cascade: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f1() {
+            var a;
+            a = typeof b === 'function' ? b() : b;
+            return a !== undefined && c();
+        }
+        function f2(b) {
+            var a;
+            b = c();
+            a = typeof b === 'function' ? b() : b;
+            return 'stirng' == typeof a && d();
+        }
+        function f3(c) {
+            var a;
+            a = b(a / 2);
+            if (a < 0) {
+                a++;
+                ++c;
+                return c / 2;
+            }
+        }
+        function f4(c) {
+            var a;
+            a = b(a / 2);
+            if (a < 0) {
+                a++;
+                c++;
+                return c / 2;
+            }
+        }
+    }
+    expect: {
+        function f1() {
+            return void 0 !== ('function' === typeof b ? b() : b) && c();
+        }
+        function f2(b) {
+            return b = c(), 'stirng' == typeof ('function' === typeof b ? b() : b) && d();
+        }
+        function f3(c) {
+            var a;
+            if ((a = b(a / 2)) < 0) return a++, ++c / 2;
+        }
+        function f4(c) {
+            var a;
+            if ((a = b(a / 2)) < 0) return a++, ++c / 2;
+        }
+    }
+}

test/compress/issue-597.js

@@ -0,0 +1,25 @@
+NaN_and_Infinity_must_have_parens: {
+    options = {};
+    input: {
+        Infinity.toString();
+        NaN.toString();
+    }
+    expect: {
+        (1/0).toString();
+        NaN.toString();         // transformation to 0/0 dropped
+    }
+}
+
+NaN_and_Infinity_should_not_be_replaced_when_they_are_redefined: {
+    options = {};
+    input: {
+        var Infinity, NaN;
+        Infinity.toString();
+        NaN.toString();
+    }
+    expect: {
+        var Infinity, NaN;
+        Infinity.toString();
+        NaN.toString();
+    }
+}

test/compress/issue-611.js

@@ -0,0 +1,21 @@
+issue_611: {
+  options = {
+    sequences: true,
+    side_effects: true
+  };
+  input: {
+    define(function() {
+      function fn() {}
+      if (fn()) {
+        fn();
+        return void 0;
+      }
+    });
+  }
+  expect: {
+    define(function() {
+      function fn(){}
+      if (fn()) return void fn();
+    });
+  }
+}

test/compress/issue-637.js

@@ -0,0 +1,22 @@
+wrongly_optimized: {
+    options = {
+        conditionals: true,
+        booleans: true,
+        evaluate: true
+    };
+    input: {
+        function func() {
+            foo();
+        }
+        if (func() || true) {
+            bar();
+        }
+    }
+    expect: {
+        function func() {
+            foo();
+        }
+        // TODO: optimize to `func(), bar()`
+        (func(), 0) || bar();
+    }
+}

test/compress/issue-640.js

@@ -0,0 +1,320 @@
+cond_5: {
+    options = {
+        conditionals: true,
+        expression: true,
+    }
+    input: {
+        if (some_condition()) {
+            if (some_other_condition()) {
+                do_something();
+            } else {
+                alternate();
+            }
+        } else {
+            alternate();
+        }
+
+        if (some_condition()) {
+            if (some_other_condition()) {
+                do_something();
+            }
+        }
+    }
+    expect: {
+        some_condition() && some_other_condition() ? do_something() : alternate();
+        if (some_condition() && some_other_condition()) do_something();
+    }
+}
+
+dead_code_const_annotation_regex: {
+    options = {
+        booleans     : true,
+        conditionals : true,
+        dead_code    : true,
+        evaluate     : true,
+        expression   : true,
+        loops        : true,
+    }
+    input: {
+        var unused;
+        // @constraint this shouldn't be a constant
+        var CONST_FOO_ANN = false;
+        if (CONST_FOO_ANN) {
+            console.log("reachable");
+        }
+    }
+    expect: {
+        var unused;
+        var CONST_FOO_ANN = !1;
+        if (CONST_FOO_ANN) console.log('reachable');
+    }
+    expect_stdout: true
+}
+
+drop_console_2: {
+    options = {
+        drop_console: true,
+        expression: true,
+    }
+    input: {
+        console.log('foo');
+        console.log.apply(console, arguments);
+    }
+    expect: {
+        // with regular compression these will be stripped out as well
+        void 0;
+        void 0;
+    }
+}
+
+drop_value: {
+    options = {
+        expression: true,
+        side_effects: true,
+    }
+    input: {
+        (1, [2, foo()], 3, {a:1, b:bar()});
+    }
+    expect: {
+        foo(), {a:1, b:bar()};
+    }
+}
+
+wrongly_optimized: {
+    options = {
+        conditionals: true,
+        booleans: true,
+        evaluate: true,
+        expression: true,
+    }
+    input: {
+        function func() {
+            foo();
+        }
+        if (func() || true) {
+            bar();
+        }
+    }
+    expect: {
+        function func() {
+            foo();
+        }
+        // TODO: optimize to `func(), bar()`
+        if (func(), !0) bar();
+    }
+}
+
+negate_iife_1: {
+    options = {
+        expression: true,
+        negate_iife: true,
+    }
+    input: {
+        (function(){ stuff() })();
+    }
+    expect: {
+        (function(){ stuff() })();
+    }
+}
+
+negate_iife_3: {
+    options = {
+        conditionals: true,
+        expression: true,
+        negate_iife: true,
+    }
+    input: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+    }
+    expect: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+    }
+}
+
+negate_iife_3_off: {
+    options = {
+        conditionals: true,
+        expression: true,
+        negate_iife: false,
+    }
+    input: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+    }
+    expect: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+    }
+}
+
+negate_iife_4: {
+    options = {
+        conditionals: true,
+        expression: true,
+        negate_iife: true,
+        sequences: true,
+    }
+    input: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        (function(){ return t })() ? console.log(true) : console.log(false), function(){
+            console.log("something");
+        }();
+    }
+}
+
+negate_iife_5: {
+    options = {
+        conditionals: true,
+        expression: true,
+        negate_iife: true,
+        sequences: true,
+    }
+    input: {
+        if ((function(){ return t })()) {
+            foo(true);
+        } else {
+            bar(false);
+        }
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        (function(){ return t })() ? foo(true) : bar(false), function(){
+            console.log("something");
+        }();
+    }
+}
+
+negate_iife_5_off: {
+    options = {
+        conditionals: true,
+        expression: true,
+        negate_iife: false,
+        sequences: true,
+    };
+    input: {
+        if ((function(){ return t })()) {
+            foo(true);
+        } else {
+            bar(false);
+        }
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        (function(){ return t })() ? foo(true) : bar(false), function(){
+            console.log("something");
+        }();
+    }
+}
+
+issue_1254_negate_iife_true: {
+    options = {
+        expression: true,
+        negate_iife: true,
+    }
+    input: {
+        (function() {
+            return function() {
+                console.log('test')
+            };
+        })()();
+    }
+    expect_exact: '(function(){return function(){console.log("test")}})()();'
+    expect_stdout: true
+}
+
+issue_1254_negate_iife_nested: {
+    options = {
+        expression: true,
+        negate_iife: true,
+    }
+    input: {
+        (function() {
+            return function() {
+                console.log('test')
+            };
+        })()()()()();
+    }
+    expect_exact: '(function(){return function(){console.log("test")}})()()()()();'
+    expect_stdout: true
+}
+
+conditional: {
+    options = {
+        expression: true,
+        pure_funcs: [ "pure" ],
+        side_effects: true,
+    }
+    input: {
+        pure(1 | a() ? 2 & b() : 7 ^ c());
+        pure(1 | a() ? 2 & b() : 5);
+        pure(1 | a() ? 4 : 7 ^ c());
+        pure(1 | a() ? 4 : 5);
+        pure(3 ? 2 & b() : 7 ^ c());
+        pure(3 ? 2 & b() : 5);
+        pure(3 ? 4 : 7 ^ c());
+        pure(3 ? 4 : 5);
+    }
+    expect: {
+        1 | a() ? b() : c();
+        1 | a() && b();
+        1 | a() || c();
+        a();
+        3 ? b() : c();
+        3 && b();
+        3 || c();
+        pure(3 ? 4 : 5);
+    }
+}
+
+limit_1: {
+    options = {
+        expression: true,
+        sequences: 3,
+    }
+    input: {
+        a;
+        b;
+        c;
+        d;
+        e;
+        f;
+        g;
+        h;
+        i;
+        j;
+        k;
+    }
+    expect: {
+        // Turned into a single return statement
+        // so it can no longer be split into lines
+        a,b,c,d,e,f,g,h,i,j,k;
+    }
+}
+
+iife: {
+    options = {
+        expression: true,
+        sequences: true,
+    }
+    input: {
+        x = 42;
+        (function a() {})();
+        !function b() {}();
+        ~function c() {}();
+        +function d() {}();
+        -function e() {}();
+        void function f() {}();
+        typeof function g() {}();
+    }
+    expect: {
+        x = 42, function a() {}(), function b() {}(), function c() {}(),
+        function d() {}(), function e() {}(), function f() {}(), typeof function g() {}();
+    }
+}

test/compress/issue-747.js

@@ -0,0 +1,37 @@
+dont_reuse_prop: {
+    mangle_props = {
+        regex: /asd/
+    };
+
+    input: {
+        var obj = {};
+        obj.a = 123;
+        obj.asd = 256;
+        console.log(obj.a);
+    }
+    expect: {
+        var obj = {};
+        obj.a = 123;
+        obj.b = 256;
+        console.log(obj.a);
+    }
+}
+
+unmangleable_props_should_always_be_reserved: {
+    mangle_props = {
+        regex: /asd/
+    };
+
+    input: {
+        var obj = {};
+        obj.asd = 256;
+        obj.a = 123;
+        console.log(obj.a);
+    }
+    expect: {
+        var obj = {};
+        obj.b = 256;
+        obj.a = 123;
+        console.log(obj.a);
+    }
+}

test/compress/issue-751.js

@@ -0,0 +1,29 @@
+negate_booleans_1: {
+    options = {
+        comparisons: true
+    };
+    input: {
+        var a = !a || !b || !c || !d || !e || !f;
+    }
+    expect: {
+        var a = !(a && b && c && d && e && f);
+    }
+}
+
+negate_booleans_2: {
+    options = {
+        comparisons: true
+    };
+    input: {
+        var match = !x &&       // should not touch this one
+            (!z || c) &&
+            (!k || d) &&
+            the_stuff();
+    }
+    expect: {
+        var match = !x &&
+            (!z || c) &&
+            (!k || d) &&
+            the_stuff();
+    }
+}

test/compress/issue-782.js

@@ -0,0 +1,27 @@
+remove_redundant_sequence_items: {
+    options = { side_effects: true };
+    input: {
+        (0, 1, eval)();
+        (0, 1, logThis)();
+        (0, 1, _decorators.logThis)();
+    }
+    expect: {
+        (0, eval)();
+        logThis();
+        (0, _decorators.logThis)();
+    }
+}
+
+dont_remove_this_binding_sequence: {
+    options = { side_effects: true };
+    input: {
+        (0, eval)();
+        (0, logThis)();
+        (0, _decorators.logThis)();
+    }
+    expect: {
+        (0, eval)();
+        logThis();
+        (0, _decorators.logThis)();
+    }
+}

test/compress/issue-892.js

@@ -0,0 +1,33 @@
+dont_mangle_arguments: {
+    mangle = {
+    };
+    options = {
+        sequences     : true,
+        properties    : true,
+        dead_code     : true,
+        drop_debugger : true,
+        conditionals  : true,
+        comparisons   : true,
+        evaluate      : true,
+        booleans      : true,
+        loops         : true,
+        unused        : true,
+        hoist_funs    : true,
+        keep_fargs    : true,
+        keep_fnames   : false,
+        hoist_vars    : true,
+        if_return     : true,
+        join_vars     : true,
+        cascade       : true,
+        side_effects  : true,
+        negate_iife   : false
+    };
+    input: {
+        (function(){
+            var arguments = arguments, not_arguments = 9;
+            console.log(not_arguments, arguments);
+        })(5,6,7);
+    }
+    expect_exact: "(function(){var arguments=arguments,o=9;console.log(o,arguments)})(5,6,7);"
+    expect_stdout: true
+}

test/compress/issue-913.js

@@ -0,0 +1,20 @@
+keep_var_for_in: {
+    options = {
+        hoist_vars: true,
+        unused: true
+    };
+    input: {
+        (function(obj){
+            var foo = 5;
+            for (var i in obj)
+                return foo;
+        })();
+    }
+    expect: {
+        (function(obj){
+            var i, foo = 5;
+            for (i in obj)
+                return foo;
+        })();
+    }
+}

test/compress/issue-926.js

@@ -0,0 +1,9 @@
+template_strings: {
+    input: {
+        foo(
+            `<span>${contents}</span>`,
+            `<a href="${url}">${text}</a>`
+        );
+    }
+    expect_exact: "foo(`<span>${contents}</span>`,`<a href=\"${url}\">${text}</a>`);"
+}

test/compress/issue-973.js

@@ -0,0 +1,97 @@
+this_binding_conditionals: {
+    options = {
+        conditionals: true,
+        evaluate    : true
+    };
+    input: {
+        (1 && a)();
+        (0 || a)();
+        (0 || 1 && a)();
+        (1 ? a : 0)();
+
+        (1 && a.b)();
+        (0 || a.b)();
+        (0 || 1 && a.b)();
+        (1 ? a.b : 0)();
+
+        (1 && a[b])();
+        (0 || a[b])();
+        (0 || 1 && a[b])();
+        (1 ? a[b] : 0)();
+
+        (1 && eval)();
+        (0 || eval)();
+        (0 || 1 && eval)();
+        (1 ? eval : 0)();
+    }
+    expect: {
+        a();
+        a();
+        a();
+        a();
+
+        (0, a.b)();
+        (0, a.b)();
+        (0, a.b)();
+        (0, a.b)();
+
+        (0, a[b])();
+        (0, a[b])();
+        (0, a[b])();
+        (0, a[b])();
+
+        (0, eval)();
+        (0, eval)();
+        (0, eval)();
+        (0, eval)();
+    }
+}
+
+this_binding_collapse_vars: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    };
+    input: {
+        var c = a; c();
+        var d = a.b; d();
+        var e = eval; e();
+    }
+    expect: {
+        a();
+        (0, a.b)();
+        (0, eval)();
+    }
+}
+
+this_binding_side_effects: {
+    options = {
+        side_effects : true
+    };
+    input: {
+        (function (foo) {
+            (0, foo)();
+            (0, foo.bar)();
+            (0, eval)('console.log(foo);');
+        }());
+        (function (foo) {
+            var eval = console;
+            (0, foo)();
+            (0, foo.bar)();
+            (0, eval)('console.log(foo);');
+        }());
+    }
+    expect: {
+        (function (foo) {
+            foo();
+            (0, foo.bar)();
+            (0, eval)('console.log(foo);');
+        }());
+        (function (foo) {
+            var eval = console;
+            foo();
+            (0, foo.bar)();
+            (0, eval)('console.log(foo);');
+        }());
+    }
+}

test/compress/issue-976.js

@@ -0,0 +1,89 @@
+eval_collapse_vars: {
+    options = {
+        collapse_vars:true, sequences:false, properties:true, dead_code:true, conditionals:true,
+        comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true
+    };
+    input: {
+        function f1() {
+            var e = 7;
+            var s = "abcdef";
+            var i = 2;
+            var eval = console.log.bind(console);
+            var x = s.charAt(i++);
+            var y = s.charAt(i++);
+            var z = s.charAt(i++);
+            eval(x, y, z, e);
+        }
+        function p1() { var a = foo(), b = bar(), eval = baz(); return a + b + eval; }
+        function p2() { var a = foo(), b = bar(), eval = baz; return a + b + eval(); }
+        (function f2(eval) {
+            var a = 2;
+            console.log(a - 5);
+            eval("console.log(a);");
+        })(eval);
+    }
+    expect: {
+        function f1() {
+            var e = 7,
+                s = "abcdef",
+                i = 2,
+                eval = console.log.bind(console),
+                x = s.charAt(i++),
+                y = s.charAt(i++),
+                z = s.charAt(i++);
+            eval(x, y, z, e);
+        }
+        function p1() { return foo() + bar() + baz(); }
+        function p2() { var a = foo(), b = bar(), eval = baz; return a + b + eval(); }
+        (function f2(eval) {
+            var a = 2;
+            console.log(a - 5);
+            eval("console.log(a);");
+        })(eval);
+    }
+    expect_stdout: true
+}
+
+eval_unused: {
+    options = { unused: true, keep_fargs: false };
+    input: {
+        function f1(a, eval, c, d, e) {
+            return a('c') + eval;
+        }
+        function f2(a, b, c, d, e) {
+            return a + eval('c');
+        }
+        function f3(a, eval, c, d, e) {
+            return a + eval('c');
+        }
+    }
+    expect: {
+        function f1(a, eval) {
+            return a('c') + eval;
+        }
+        function f2(a, b, c, d, e) {
+            return a + eval('c');
+        }
+        function f3(a, eval, c, d, e) {
+            return a + eval('c');
+        }
+    }
+}
+
+eval_mangle: {
+    mangle = {
+    };
+    input: {
+        function f1(a, eval, c, d, e) {
+            return a('c') + eval;
+        }
+        function f2(a, b, c, d, e) {
+            return a + eval('c');
+        }
+        function f3(a, eval, c, d, e) {
+            return a + eval('c');
+        }
+    }
+    expect_exact: 'function f1(n,c,e,a,f){return n("c")+c}function f2(a,b,c,d,e){return a+eval("c")}function f3(a,eval,c,d,e){return a+eval("c")}'
+}

test/compress/issue-979.js

@@ -0,0 +1,89 @@
+issue979_reported: {
+    options = {
+        sequences:true, properties:true, dead_code:true, conditionals:true,
+        comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true
+    }
+    input: {
+        function f1() {
+            if (a == 1 || b == 2) {
+                foo();
+            }
+        }
+        function f2() {
+            if (!(a == 1 || b == 2)) {
+            }
+            else {
+                foo();
+            }
+        }
+    }
+    expect: {
+        function f1() {
+            1!=a&&2!=b||foo();
+        }
+        function f2() {
+            1!=a&&2!=b||foo();
+        }
+    }
+}
+
+issue979_test_negated_is_best: {
+    options = {
+        sequences:true, properties:true, dead_code:true, conditionals:true,
+        comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true
+    }
+    input: {
+        function f3() {
+            if (a == 1 | b == 2) {
+                foo();
+            }
+        }
+        function f4() {
+            if (!(a == 1 | b == 2)) {
+            }
+            else {
+                foo();
+            }
+        }
+        function f5() {
+            if (a == 1 && b == 2) {
+                foo();
+            }
+        }
+        function f6() {
+            if (!(a == 1 && b == 2)) {
+            }
+            else {
+                foo();
+            }
+        }
+        function f7() {
+            if (a == 1 || b == 2) {
+                foo();
+            }
+            else {
+                return bar();
+            }
+        }
+    }
+    expect: {
+        function f3() {
+            1==a|2==b&&foo();
+        }
+        function f4() {
+            1==a|2==b&&foo();
+        }
+        function f5() {
+            1==a&&2==b&&foo();
+        }
+        function f6() {
+            1!=a||2!=b||foo();
+        }
+        function f7() {
+            if(1!=a&&2!=b)return bar();foo()
+        }
+    }
+}
+

test/compress/join-vars.js

@@ -0,0 +1,40 @@
+only_vars: {
+    options = { join_vars: true };
+    input: {
+        let netmaskBinary = '';
+        for (let i = 0; i < netmaskBits; ++i) {
+            netmaskBinary += '1';
+        }
+    }
+    expect: {
+        let netmaskBinary = '';
+        for (let i = 0; i < netmaskBits; ++i) netmaskBinary += '1';
+    }
+}
+
+issue_1079_with_vars: {
+    options = { join_vars: true };
+    input: {
+        var netmaskBinary = '';
+        for (var i = 0; i < netmaskBits; ++i) {
+            netmaskBinary += '1';
+        }
+    }
+    expect: {
+        for (var netmaskBinary = '', i = 0; i < netmaskBits; ++i) netmaskBinary += '1';
+    }
+}
+
+issue_1079_with_mixed: {
+    options = { join_vars: true };
+    input: {
+        var netmaskBinary = '';
+        for (let i = 0; i < netmaskBits; ++i) {
+            netmaskBinary += '1';
+        }
+    }
+    expect: {
+        var netmaskBinary = ''
+        for (let i = 0; i < netmaskBits; ++i) netmaskBinary += '1';
+    }
+}

test/compress/labels.js

@@ -9,6 +9,7 @@ labels_1: {
     expect: {
         foo || console.log("bar");
     }
+    expect_stdout: true
 }
 
 labels_2: {
@@ -40,6 +41,7 @@ labels_3: {
         for (var i = 0; i < 5; ++i)
             i < 3 || console.log(i);
     }
+    expect_stdout: true
 }
 
 labels_4: {
@@ -54,6 +56,7 @@ labels_4: {
         for (var i = 0; i < 5; ++i)
             i < 3 || console.log(i);
     }
+    expect_stdout: true
 }
 
 labels_5: {

test/compress/loops.js

@@ -121,3 +121,322 @@ drop_if_else_break_4: {
         for (; bar() && (x(), y(), foo());) baz(), z(), k();
     }
 }
+
+parse_do_while_with_semicolon: {
+    options = { loops: false };
+    input: {
+        do {
+            x();
+        } while (false);y()
+    }
+    expect: {
+        do x(); while (false);y();
+    }
+}
+
+parse_do_while_without_semicolon: {
+    options = { loops: false };
+    input: {
+        do {
+            x();
+        } while (false)y()
+    }
+    expect: {
+        do x(); while (false);y();
+    }
+}
+
+
+keep_collapse_const_in_own_block_scope: {
+    options = {
+        join_vars: true,
+        loops: true
+    }
+    input: {
+        var i=2;
+        const c=5;
+        while(i--)
+            console.log(i);
+        console.log(c);
+    }
+    expect: {
+        var i=2;
+        const c=5;
+        for(;i--;)
+            console.log(i);
+        console.log(c);
+    }
+    expect_stdout: true
+}
+
+keep_collapse_const_in_own_block_scope_2: {
+    options = {
+        join_vars: true,
+        loops: true
+    }
+    input: {
+        const c=5;
+        var i=2; // Moves to loop, while it did not in previous test
+        while(i--)
+            console.log(i);
+        console.log(c);
+    }
+    expect: {
+        const c=5;
+        for(var i=2;i--;)
+            console.log(i);
+        console.log(c);
+    }
+    expect_stdout: true
+}
+
+evaluate: {
+    options = {
+        loops: true,
+        dead_code: true,
+        evaluate: true,
+    };
+    input: {
+        while (true) {
+            a();
+        }
+        while (false) {
+            b();
+        }
+        do {
+            c();
+        } while (true);
+        do {
+            d();
+        } while (false);
+    }
+    expect: {
+        for(;;)
+            a();
+        for(;;)
+            c();
+        // rule disabled due to issue_1532
+        do d(); while (false);
+    }
+}
+
+issue_1532: {
+    options = {
+        evaluate: true,
+        loops: true,
+    }
+    input: {
+        function f(x, y) {
+            do {
+                if (x) break;
+                foo();
+            } while (false);
+        }
+    }
+    expect: {
+        function f(x, y) {
+            do {
+                if (x) break;
+                foo();
+            } while (false);
+        }
+    }
+}
+
+issue_186: {
+    beautify = {
+        beautify: false,
+        screw_ie8: true,
+    }
+    input: {
+        var x = 3;
+        if (foo())
+            do
+                do
+                    alert(x);
+                while (--x);
+            while (x);
+        else
+            bar();
+    }
+    expect_exact: 'var x=3;if(foo())do{do{alert(x)}while(--x)}while(x);else bar();'
+}
+
+issue_186_ie8: {
+    beautify = {
+        beautify: false,
+        screw_ie8: false,
+    }
+    input: {
+        var x = 3;
+        if (foo())
+            do
+                do
+                    alert(x);
+                while (--x);
+            while (x);
+        else
+            bar();
+    }
+    expect_exact: 'var x=3;if(foo()){do{do{alert(x)}while(--x)}while(x)}else bar();'
+}
+
+issue_186_beautify: {
+    beautify = {
+        beautify: true,
+        screw_ie8: true,
+    }
+    input: {
+        var x = 3;
+        if (foo())
+            do
+                do
+                    alert(x);
+                while (--x);
+            while (x);
+        else
+            bar();
+    }
+    expect_exact: [
+        'var x = 3;',
+        '',
+        'if (foo()) do {',
+        '    do {',
+        '        alert(x);',
+        '    } while (--x);',
+        '} while (x); else bar();',
+    ]
+}
+
+issue_186_beautify_ie8: {
+    beautify = {
+        beautify: true,
+        screw_ie8: false,
+    }
+    input: {
+        var x = 3;
+        if (foo())
+            do
+                do
+                    alert(x);
+                while (--x);
+            while (x);
+        else
+            bar();
+    }
+    expect_exact: [
+        'var x = 3;',
+        '',
+        'if (foo()) {',
+        '    do {',
+        '        do {',
+        '            alert(x);',
+        '        } while (--x);',
+        '    } while (x);',
+        '} else bar();',
+    ]
+}
+
+issue_186_bracketize: {
+    beautify = {
+        beautify: false,
+        bracketize: true,
+        screw_ie8: true,
+    }
+    input: {
+        var x = 3;
+        if (foo())
+            do
+                do
+                    alert(x);
+                while (--x);
+            while (x);
+        else
+            bar();
+    }
+    expect_exact: 'var x=3;if(foo()){do{do{alert(x)}while(--x)}while(x)}else{bar()}'
+}
+
+issue_186_bracketize_ie8: {
+    beautify = {
+        beautify: false,
+        bracketize: true,
+        screw_ie8: false,
+    }
+    input: {
+        var x = 3;
+        if (foo())
+            do
+                do
+                    alert(x);
+                while (--x);
+            while (x);
+        else
+            bar();
+    }
+    expect_exact: 'var x=3;if(foo()){do{do{alert(x)}while(--x)}while(x)}else{bar()}'
+}
+
+issue_186_beautify_bracketize: {
+    beautify = {
+        beautify: true,
+        bracketize: true,
+        screw_ie8: true,
+    }
+    input: {
+        var x = 3;
+        if (foo())
+            do
+                do
+                    alert(x);
+                while (--x);
+            while (x);
+        else
+            bar();
+    }
+    expect_exact: [
+        'var x = 3;',
+        '',
+        'if (foo()) {',
+        '    do {',
+        '        do {',
+        '            alert(x);',
+        '        } while (--x);',
+        '    } while (x);',
+        '} else {',
+        '    bar();',
+        '}',
+    ]
+}
+
+issue_186_beautify_bracketize_ie8: {
+    beautify = {
+        beautify: true,
+        bracketize: true,
+        screw_ie8: false,
+    }
+    input: {
+        var x = 3;
+        if (foo())
+            do
+                do
+                    alert(x);
+                while (--x);
+            while (x);
+        else
+            bar();
+    }
+    expect_exact: [
+        'var x = 3;',
+        '',
+        'if (foo()) {',
+        '    do {',
+        '        do {',
+        '            alert(x);',
+        '        } while (--x);',
+        '    } while (x);',
+        '} else {',
+        '    bar();',
+        '}',
+    ]
+}

test/compress/max_line_len.js

@@ -0,0 +1,39 @@
+too_short: {
+    beautify = {
+        max_line_len: 10,
+    }
+    input: {
+        function f(a) {
+            return { c: 42, d: a(), e: "foo"};
+        }
+    }
+    expect_exact: [
+        'function f(a){',
+        'return{',
+        'c:42,',
+        'd:a(),',
+        'e:"foo"}}',
+    ]
+    expect_warnings: [
+        "WARN: Output exceeds 10 characters"
+    ]
+}
+
+just_enough: {
+    beautify = {
+        max_line_len: 14,
+    }
+    input: {
+        function f(a) {
+            return { c: 42, d: a(), e: "foo"};
+        }
+    }
+    expect_exact: [
+        'function f(a){',
+        'return{c:42,',
+        'd:a(),e:"foo"}',
+        '}',
+    ]
+    expect_warnings: [
+    ]
+}

test/compress/negate-iife.js

@@ -0,0 +1,417 @@
+negate_iife_1: {
+    options = {
+        negate_iife: true
+    };
+    input: {
+        (function(){ stuff() })();
+    }
+    expect: {
+        !function(){ stuff() }();
+    }
+}
+
+negate_iife_1_off: {
+    options = {
+        negate_iife: false,
+    };
+    input: {
+        (function(){ stuff() })();
+    }
+    expect_exact: '(function(){stuff()})();'
+}
+
+negate_iife_2: {
+    options = {
+        negate_iife: true
+    };
+    input: {
+        (function(){ return {} })().x = 10; // should not transform this one
+    }
+    expect: {
+        (function(){ return {} })().x = 10;
+    }
+}
+
+negate_iife_2_side_effects: {
+    options = {
+        negate_iife: true,
+        side_effects: true,
+    }
+    input: {
+        (function(){ return {} })().x = 10; // should not transform this one
+    }
+    expect: {
+        (function(){ return {} })().x = 10;
+    }
+}
+
+negate_iife_3: {
+    options = {
+        negate_iife: true,
+        conditionals: true
+    };
+    input: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+    }
+    expect: {
+        !function(){ return t }() ? console.log(false) : console.log(true);
+    }
+}
+
+negate_iife_3_evaluate: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        negate_iife: true,
+    }
+    input: {
+        (function(){ return true })() ? console.log(true) : console.log(false);
+    }
+    expect: {
+        console.log(true);
+    }
+    expect_stdout: true
+}
+
+negate_iife_3_side_effects: {
+    options = {
+        conditionals: true,
+        negate_iife: true,
+        side_effects: true,
+    }
+    input: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+    }
+    expect: {
+        !function(){ return t }() ? console.log(false) : console.log(true);
+    }
+}
+
+negate_iife_3_off: {
+    options = {
+        negate_iife: false,
+        conditionals: true,
+    };
+    input: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+    }
+    expect: {
+        !function(){ return t }() ? console.log(false) : console.log(true);
+    }
+}
+
+negate_iife_3_off_evaluate: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        negate_iife: false,
+    }
+    input: {
+        (function(){ return true })() ? console.log(true) : console.log(false);
+    }
+    expect: {
+        console.log(true);
+    }
+    expect_stdout: true
+}
+
+negate_iife_4: {
+    options = {
+        negate_iife: true,
+        conditionals: true,
+        sequences: true
+    };
+    input: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        !function(){ return t }() ? console.log(false) : console.log(true), function(){
+            console.log("something");
+        }();
+    }
+}
+
+sequence_off: {
+    options = {
+        negate_iife: false,
+        conditionals: true,
+        sequences: true,
+        passes: 2,
+    };
+    input: {
+        function f() {
+            (function(){ return t })() ? console.log(true) : console.log(false);
+            (function(){
+                console.log("something");
+            })();
+        }
+        function g() {
+            (function(){
+                console.log("something");
+            })();
+            (function(){ return t })() ? console.log(true) : console.log(false);
+        }
+    }
+    expect: {
+        function f() {
+            !function(){ return t }() ? console.log(false) : console.log(true), function(){
+                console.log("something");
+            }();
+        }
+        function g() {
+            (function(){
+                console.log("something");
+            })(), function(){ return t }() ? console.log(true) : console.log(false);
+        }
+    }
+}
+
+negate_iife_5: {
+    options = {
+        negate_iife: true,
+        sequences: true,
+        conditionals: true,
+    };
+    input: {
+        if ((function(){ return t })()) {
+            foo(true);
+        } else {
+            bar(false);
+        }
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        !function(){ return t }() ? bar(false) : foo(true), function(){
+            console.log("something");
+        }();
+    }
+}
+
+negate_iife_5_off: {
+    options = {
+        negate_iife: false,
+        sequences: true,
+        conditionals: true,
+    };
+    input: {
+        if ((function(){ return t })()) {
+            foo(true);
+        } else {
+            bar(false);
+        }
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        !function(){ return t }() ? bar(false) : foo(true), function(){
+            console.log("something");
+        }();
+    }
+}
+
+negate_iife_nested: {
+    options = {
+        negate_iife: true,
+        sequences: true,
+        conditionals: true,
+    };
+    input: {
+        function Foo(f) {
+            this.f = f;
+        }
+        new Foo(function() {
+            (function(x) {
+                (function(y) {
+                    console.log(y);
+                })(x);
+            })(7);
+        }).f();
+    }
+    expect: {
+        function Foo(f) {
+            this.f = f;
+        }
+        new Foo(function() {
+            !function(x) {
+                !function(y) {
+                    console.log(y);
+                }(x);
+            }(7);
+        }).f();
+    }
+    expect_stdout: true
+}
+
+negate_iife_nested_off: {
+    options = {
+        negate_iife: false,
+        sequences: true,
+        conditionals: true,
+    };
+    input: {
+        function Foo(f) {
+            this.f = f;
+        }
+        new Foo(function() {
+            (function(x) {
+                (function(y) {
+                    console.log(y);
+                })(x);
+            })(7);
+        }).f();
+    }
+    expect: {
+        function Foo(f) {
+            this.f = f;
+        }
+        new Foo(function() {
+            (function(x) {
+                (function(y) {
+                    console.log(y);
+                })(x);
+            })(7);
+        }).f();
+    }
+    expect_stdout: true
+}
+
+negate_iife_issue_1073: {
+    options = {
+        negate_iife: true,
+        sequences: true,
+        conditionals: true,
+    };
+    input: {
+        new (function(a) {
+            return function Foo() {
+                this.x = a;
+                console.log(this);
+            };
+        }(7))();
+    }
+    expect: {
+        new (function(a) {
+            return function Foo() {
+                this.x = a,
+                console.log(this);
+            };
+        }(7))();
+    }
+    expect_stdout: true
+}
+
+issue_1254_negate_iife_false: {
+    options = {
+        negate_iife: false,
+    }
+    input: {
+        (function() {
+            return function() {
+                console.log('test')
+            };
+        })()();
+    }
+    expect_exact: '(function(){return function(){console.log("test")}})()();'
+    expect_stdout: true
+}
+
+issue_1254_negate_iife_true: {
+    options = {
+        negate_iife: true,
+    }
+    input: {
+        (function() {
+            return function() {
+                console.log('test')
+            };
+        })()();
+    }
+    expect_exact: '!function(){return function(){console.log("test")}}()();'
+    expect_stdout: true
+}
+
+issue_1254_negate_iife_nested: {
+    options = {
+        negate_iife: true,
+    }
+    input: {
+        (function() {
+            return function() {
+                console.log('test')
+            };
+        })()()()()();
+    }
+    expect_exact: '!function(){return function(){console.log("test")}}()()()()();'
+    expect_stdout: true
+}
+
+issue_1288: {
+    options = {
+        negate_iife: true,
+        conditionals: true,
+    };
+    input: {
+        if (w) ;
+        else {
+            (function f() {})();
+        }
+        if (!x) {
+            (function() {
+                x = {};
+            })();
+        }
+        if (y)
+            (function() {})();
+        else
+            (function(z) {
+                return z;
+            })(0);
+    }
+    expect: {
+        w || function f() {}();
+        x || function() {
+            x = {};
+        }();
+        y ? function() {}() : function(z) {
+            return z;
+        }(0);
+    }
+}
+
+issue_1288_side_effects: {
+    options = {
+        conditionals: true,
+        negate_iife: true,
+        side_effects: true,
+    }
+    input: {
+        if (w) ;
+        else {
+            (function f() {})();
+        }
+        if (!x) {
+            (function() {
+                x = {};
+            })();
+        }
+        if (y)
+            (function() {})();
+        else
+            (function(z) {
+                return z;
+            })(0);
+    }
+    expect: {
+        w;
+        x || function() {
+            x = {};
+        }();
+        y;
+    }
+}

test/compress/new.js

@@ -0,0 +1,100 @@
+new_statement: {
+    input: {
+        new x(1);
+        new x(1)(2);
+        new x(1)(2)(3);
+        new new x(1);
+        new new x(1)(2);
+        new (new x(1))(2);
+        (new new x(1))(2);
+    }
+    expect_exact: "new x(1);new x(1)(2);new x(1)(2)(3);new new x(1);new new x(1)(2);new new x(1)(2);(new new x(1))(2);"
+}
+
+new_statements_2: {
+    input: {
+        new x;
+        new new x;
+        new new new x;
+        new true;
+        new (0);
+        new (!0);
+        new (bar = function(foo) {this.foo=foo;})(123);
+        new (bar = function(foo) {this.foo=foo;})();
+    }
+    expect_exact: "new x;new(new x);new(new(new x));new true;new 0;new(!0);new(bar=function(foo){this.foo=foo})(123);new(bar=function(foo){this.foo=foo});"
+}
+
+new_statements_3: {
+    input: {
+        new (function(foo){this.foo=foo;})(1);
+        new (function(foo){this.foo=foo;})();
+        new (function test(foo){this.foo=foo;})(1);
+        new (function test(foo){this.foo=foo;})();
+    }
+    expect_exact: "new function(foo){this.foo=foo}(1);new function(foo){this.foo=foo};new function test(foo){this.foo=foo}(1);new function test(foo){this.foo=foo};"
+}
+
+new_with_rewritten_true_value: {
+    options = { booleans: true }
+    input: {
+        new true;
+    }
+    expect_exact: "new(!0);"
+}
+
+new_with_many_parameters: {
+    input: {
+        new foo.bar("baz");
+        new x(/123/, 456);
+    }
+    expect_exact: 'new foo.bar("baz");new x(/123/,456);'
+}
+
+new_constructor_with_unary_arguments: {
+    input: {
+        new x();
+        new x(-1);
+        new x(-1, -2);
+        new x(void 1, +2, -3, ~4, !5, --a, ++b, c--, d++, typeof e, delete f);
+        new (-1);     // should parse despite being invalid at runtime.
+        new (-1)();   // should parse despite being invalid at runtime.
+        new (-1)(-2); // should parse despite being invalid at runtime.
+    }
+    expect_exact: "new x;new x(-1);new x(-1,-2);new x(void 1,+2,-3,~4,!5,--a,++b,c--,d++,typeof e,delete f);new(-1);new(-1);new(-1)(-2);"
+}
+
+call_with_unary_arguments: {
+    input: {
+        x();
+        x(-1);
+        x(-1, -2);
+        x(void 1, +2, -3, ~4, !5, --a, ++b, c--, d++, typeof e, delete f);
+        (-1)();   // should parse despite being invalid at runtime.
+        (-1)(-2); // should parse despite being invalid at runtime.
+    }
+    expect_exact: "x();x(-1);x(-1,-2);x(void 1,+2,-3,~4,!5,--a,++b,c--,d++,typeof e,delete f);(-1)();(-1)(-2);"
+}
+
+new_with_unary_prefix: {
+    input: {
+        var bar = (+new Date()).toString(32);
+    }
+    expect_exact: 'var bar=(+new Date).toString(32);';
+}
+
+new_with_assignement_expression: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a;
+        new x(a = 5 * 2, b = [1, 2, 3], c = {a: "a", b: "b", cd: "c" + "d"});
+        new y([a, b] = [3, 4]);
+    }
+    expect: {
+        var a;
+        new x(a = 10, b = [1, 2, 3], c = {a: "a", b: "b", cd: "cd"});
+        new y([a, b] = [3, 4]);
+    }
+}

test/compress/numbers.js

@@ -0,0 +1,155 @@
+hex_numbers_in_parentheses_for_prototype_functions: {
+    input: {
+        (-2);
+        (-2).toFixed(0);
+
+        (2);
+        (2).toFixed(0);
+
+        (0.2);
+        (0.2).toFixed(0);
+
+        (0.00000002);
+        (0.00000002).toFixed(0);
+
+        (1000000000000000128);
+        (1000000000000000128).toFixed(0);
+    }
+    expect_exact: "-2;(-2).toFixed(0);2;2..toFixed(0);.2;.2.toFixed(0);2e-8;2e-8.toFixed(0);0xde0b6b3a7640080;(0xde0b6b3a7640080).toFixed(0);"
+}
+
+comparisons: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        console.log(
+            ~x === 42,
+            x % n === 42
+        );
+    }
+    expect: {
+        console.log(
+            42 == ~x,
+            x % n == 42
+        );
+    }
+}
+
+evaluate_1: {
+    options = {
+        evaluate: true,
+        unsafe_math: false,
+    }
+    input: {
+        console.log(
+            x + 1 + 2,
+            x * 1 * 2,
+            +x + 1 + 2,
+            1 + x + 2 + 3,
+            1 | x | 2 | 3,
+            1 + x-- + 2 + 3,
+            1 + (x*y + 2) + 3,
+            1 + (2 + x + 3),
+            1 + (2 + ~x + 3),
+            -y + (2 + ~x + 3),
+            1 & (2 & x & 3),
+            1 + (2 + (x |= 0) + 3)
+        );
+    }
+    expect: {
+        console.log(
+            x + 1 + 2,
+            1 * x * 2,
+            +x + 1 + 2,
+            1 + x + 2 + 3,
+            3 | x,
+            1 + x-- + 2 + 3,
+            x*y + 2 + 1 + 3,
+            1 + (2 + x + 3),
+            2 + ~x + 3 + 1,
+            -y + (2 + ~x + 3),
+            0 & x,
+            2 + (x |= 0) + 3 + 1
+        );
+    }
+}
+
+evaluate_2: {
+    options = {
+        evaluate: true,
+        unsafe_math: true,
+    }
+    input: {
+        console.log(
+            x + 1 + 2,
+            x * 1 * 2,
+            +x + 1 + 2,
+            1 + x + 2 + 3,
+            1 | x | 2 | 3,
+            1 + x-- + 2 + 3,
+            1 + (x*y + 2) + 3,
+            1 + (2 + x + 3),
+            1 & (2 & x & 3),
+            1 + (2 + (x |= 0) + 3)
+        );
+    }
+    expect: {
+        console.log(
+            x + 1 + 2,
+            2 * x,
+            3 + +x,
+            1 + x + 2 + 3,
+            3 | x,
+            6 + x--,
+            6 + x*y,
+            1 + (2 + x + 3),
+            0 & x,
+            6 + (x |= 0)
+        );
+    }
+}
+
+evaluate_3: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+        unsafe_math: true,
+    }
+    input: {
+        console.log(1 + Number(x) + 2);
+    }
+    expect: {
+        console.log(3 + +x);
+    }
+}
+
+evaluate_4: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log(
+            1+ +a,
+            +a+1,
+            1+-a,
+            -a+1,
+            +a+ +b,
+            +a+-b,
+            -a+ +b,
+            -a+-b
+        );
+    }
+    expect: {
+        console.log(
+            +a+1,
+            +a+1,
+            1-a,
+            1-a,
+            +a+ +b,
+            +a-b,
+            -a+ +b,
+            -a-b
+        );
+    }
+}

test/compress/object.js

@@ -0,0 +1,512 @@
+getter_setter: {
+    input: {
+        var get = "bar";
+        var a = {
+            get,
+            set: "foo",
+            get bar() {
+                return this.get;
+            },
+            get 5() {
+                return "five";
+            },
+            get 0xf55() {
+                return "f five five";
+            },
+            get "five"() {
+                return 5;
+            },
+            set one(value) {
+                this._one = value;
+            },
+            set 9(value) {
+                this._nine = value;
+            },
+            set 0b1010(value) {
+                this._ten = value;
+            },
+            set "eleven"(value) {
+                this._eleven = value;
+            }
+        };
+        var b = {
+            get() { return "gift"; },
+            set: function(code) { return "Storing code " + code; }
+        };
+        var c = {
+            ["get"]: "foo",
+            ["set"]: "bar"
+        };
+        var d = {
+            get: "foo",
+            set: "bar"
+        };
+    }
+    expect: {
+        var get = "bar";
+        var a = {
+            get,
+            set: "foo",
+            get bar() {
+                return this.get;
+            },
+            get 5() {
+                return "five";
+            },
+            get 0xf55() {
+                return "f five five";
+            },
+            get "five"() {
+                return 5;
+            },
+            set one(value) {
+                this._one = value;
+            },
+            set 9(value) {
+                this._nine = value;
+            },
+            set 0b1010(value) {
+                this._ten = value;
+            },
+            set "eleven"(value) {
+                this._eleven = value;
+            }
+        };
+        var b = {
+            get() { return "gift"; },
+            set: function(code) { return "Storing code " + code; }
+        };
+        var c = {
+            ["get"]: "foo",
+            ["set"]: "bar"
+        };
+        var d = {
+            get: "foo",
+            set: "bar"
+        };
+    }
+}
+
+getter_setter_mangler: {
+    mangle = {}
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        function f(get,set) {
+            return {
+                get,
+                set,
+                get g(){},
+                set s(n){},
+                c,
+                a:1,
+                m(){}
+            };
+        }
+    }
+    expect_exact: "function f(n,t){return{get:n,set:t,get g(){},set s(n){},c,a:1,m(){}}}"
+}
+
+use_shorthand_opportunity: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        var foo = 123;
+        var obj = {foo: foo};
+    }
+    expect_exact: "var foo=123;var obj={foo};"
+}
+
+computed_property_names: {
+    input: {
+        obj({ ["x" + "x"]: 6 });
+    }
+    expect_exact: 'obj({["x"+"x"]:6});'
+}
+
+computed_property_names_evaluated_1: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        obj({
+            [1 + 1]: 2,
+            ["x" + "x"]: 6
+        });
+    }
+    expect_exact: 'obj({[2]:2,["xx"]:6});'
+}
+
+computed_property_names_evaluated_2: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var foo = something();
+
+        var obj = {
+            [foo]() {
+                return "blah";
+            }
+        }
+    }
+    expect_exact: 'var foo=something();var obj={[foo](){return"blah"}};'
+}
+
+shorthand_properties: {
+    mangle = true;
+    input: {
+        (function() {
+            var prop = 1;
+            const value = {prop};
+            return value;
+        })();
+    }
+    expect: {
+        (function() {
+            var n = 1;
+            const r = {prop:n};
+            return r;
+        })();
+    }
+}
+
+concise_methods: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        x = {
+            foo(a, b) {
+                return x;
+            }
+        }
+        y = {
+            foo([{a}]) {
+                return a;
+            },
+            bar(){}
+        }
+    }
+    expect_exact: "x={foo(a,b){return x}};y={foo([{a}]){return a},bar(){}};"
+}
+
+concise_methods_with_computed_property: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var foo = {
+            [Symbol.iterator]() {
+                return { /* stuff */ }
+            },
+            [1 + 2]() {
+                return 3;
+            },
+            ["1" + "4"]() {
+                return 14;
+            }
+        }
+    }
+    expect: {
+        var foo = {
+            [Symbol.iterator]() {
+                return { /* stuff */ }
+            },
+            [3]() {
+                return 3;
+            },
+            ["14"]() {
+                return 14;
+            }
+        }
+    }
+}
+
+concise_methods_with_computed_property2: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var foo = {
+            [[1]](){
+                return "success";
+            }
+        };
+        doSomething(foo[[1]]());
+    }
+    expect_exact: 'var foo={[[1]](){return"success"}};doSomething(foo[[1]]());'
+}
+
+concise_methods_with_various_property_names: {
+    input: {
+        var get = "bar";
+        var a = {
+            bar() {
+                return this.get;
+            },
+            5() {
+                return "five";
+            },
+            0xf55() {
+                return "f five five";
+            },
+            "five"() {
+                return 5;
+            },
+            0b1010(value) {
+                this._ten = value;
+            }
+        };
+    }
+    expect: {
+        var get = "bar";
+        var a = {
+            bar() {
+                return this.get;
+            },
+            5() {
+                return "five";
+            },
+            0xf55() {
+                return "f five five";
+            },
+            "five"() {
+                return 5;
+            },
+            0b1010(value) {
+                this._ten = value;
+            }
+        };
+    }
+}
+
+concise_methods_and_mangle_props: {
+    mangle_props = {
+        regex: /_/
+    };
+    input: {
+        function x() {
+            obj = {
+                _foo() { return 1; }
+            }
+        }
+    }
+    expect: {
+        function x() {
+            obj = {
+                a() { return 1; }
+            }
+        }
+    }
+}
+
+concise_generators: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        x = {
+            *foo(a, b) {
+                return x;
+            }
+        }
+        y = {
+            *foo([{a}]) {
+                yield a;
+            },
+            bar(){}
+        }
+    }
+    expect_exact: "x={*foo(a,b){return x}};y={*foo([{a}]){yield a},bar(){}};"
+}
+
+concise_methods_and_keyword_names: {
+    input: {
+        x = {
+            catch() {},
+            throw() {}
+        }
+    }
+    expect: {
+        x={catch(){},throw(){}};
+    }
+}
+
+getter_setter_with_computed_value: {
+    input: {
+        class C {
+            get ['a']() {
+                return 'A';
+            }
+            set ['a'](value) {
+                do_something(a);
+            }
+        }
+        var x = {
+            get [a.b]() {
+                return 42;
+            }
+        };
+        class MyArray extends Array {
+            get [Symbol.species]() {
+                return Array;
+            }
+        }
+    }
+    expect_exact: 'class C{get["a"](){return"A"}set["a"](value){do_something(a)}}var x={get[a.b](){return 42}};class MyArray extends Array{get[Symbol.species](){return Array}}'
+}
+
+property_with_operator_value: {
+    input: {
+        var foo = {
+            "*": 1,
+            get "*"() {
+                return 2;
+            },
+            *"*"() {
+                return 3;
+            },
+            "%": 1,
+            get "%"() {
+                return 2;
+            },
+            *"%"() {
+                return 3;
+            }
+        }
+        class bar {
+            get "*"() {
+                return 1
+            }
+            *"*"() {
+                return 2;
+            }
+            get "%"() {
+                return 1
+            }
+            *"%"() {
+                return 2;
+            }
+        }
+    }
+    expect_exact: 'var foo={"*":1,get"*"(){return 2},*"*"(){return 3},"%":1,get"%"(){return 2},*"%"(){return 3}};class bar{get"*"(){return 1}*"*"(){return 2}get"%"(){return 1}*"%"(){return 2}}'
+}
+
+property_with_unprintable: {
+    input: {
+        var foo = {
+            "\x00\x01": "foo",
+            get "\x00\x01"() {
+                return "bar";
+            },
+            set "\x00\x01"(foo) {
+                save(foo);
+            },
+            *"\x00\x01"() {
+                return "foobar";
+            }
+        }
+        class bar {
+            get "\x00\x01"() {
+                return "bar"
+            }
+            set "\x00\x01"(foo) {
+                save(foo);
+            }
+            *"\x00\x01"() {
+                return "foobar";
+            }
+        }
+    }
+    expect_exact: 'var foo={"\\0\x01":"foo",get"\\0\x01"(){return"bar"},set"\\0\x01"(foo){save(foo)},*"\\0\x01"(){return"foobar"}};class bar{get"\\0\x01"(){return"bar"}set"\\0\x01"(foo){save(foo)}*"\\0\x01"(){return"foobar"}}'
+}
+
+property_with_unprintable_ascii_only: {
+    beautify = {
+        ascii_only: true,
+    }
+    input: {
+        var foo = {
+            "\x00\x01": "foo",
+            get "\x00\x01"() {
+                return "bar";
+            },
+            set "\x00\x01"(foo) {
+                save(foo);
+            },
+            *"\x00\x01"() {
+                return "foobar";
+            }
+        }
+        class bar {
+            get "\x00\x01"() {
+                return "bar"
+            }
+            set "\x00\x01"(foo) {
+                save(foo);
+            }
+            *"\x00\x01"() {
+                return "foobar";
+            }
+        }
+    }
+    expect_exact: 'var foo={"\\0\\x01":"foo",get"\\0\\x01"(){return"bar"},set"\\0\\x01"(foo){save(foo)},*"\\0\\x01"(){return"foobar"}};class bar{get"\\0\\x01"(){return"bar"}set"\\0\\x01"(foo){save(foo)}*"\\0\\x01"(){return"foobar"}}'
+}
+
+property_with_unprintable_ascii_only_static: {
+    beautify = {
+        ascii_only: true
+    }
+    input: {
+        class foo {
+            static get "\x02\x03"() {
+                return "bar";
+            }
+            static set "\x04\x05"(foo) {
+                save(foo);
+            }
+        }
+    }
+    expect_exact: 'class foo{static get"\\x02\\x03"(){return"bar"}static set"\\x04\\x05"(foo){save(foo)}}'
+}
+
+methods_and_getters_with_keep_quoted_props_enabled: {
+    beautify = {
+        quote_style: 3,
+        keep_quoted_props: true,
+    }
+    input: {
+        var obj = {
+            a() {},
+            "b"() {},
+            get c() { return "c"},
+            get "d"() { return "d"},
+            set e(a) { doSomething(a); },
+            set f(a) { doSomething(b); }
+        }
+    }
+    expect_exact: 'var obj={a(){},"b"(){},get c(){return"c"},get"d"(){return"d"},set e(a){doSomething(a)},set f(a){doSomething(b)}};'
+}
+
+allow_assignments_to_property_values: {
+    input: {
+        var foo = {123: foo = 123} = {foo: "456"};
+    }
+    expect: {
+        var foo = {123: foo = 123} = {foo: "456"};
+    }
+}
+
+variable_as_computed_property: {
+    input: {
+        function getLine(header) {
+            return {
+                [header]: {}
+            };
+        }
+    }
+    expect_exact: "function getLine(header){return{[header]:{}}}"
+}

test/compress/parameters.js

@@ -0,0 +1,168 @@
+arrow_functions: {
+    input: {
+        (a) => b;  // 1 args
+        (a, b) => c;  // n args
+        () => b;  // 0 args
+        (a) => (b) => c;  // func returns func returns func
+        (a) => ((b) => c);  // So these parens are dropped
+        () => (b,c) => d;  // func returns func returns func
+        a=>{return b;}
+        a => 'lel';  // Dropping the parens
+    }
+    expect_exact: "a=>b;(a,b)=>c;()=>b;a=>b=>c;a=>b=>c;()=>(b,c)=>d;a=>{return b};a=>\"lel\";"
+}
+
+regression_arrow_functions_and_hoist: {
+    options = {
+        hoist_vars: true,
+        hoist_funs: true
+    }
+    input: {
+        (a) => b;
+    }
+    expect_exact: "a=>b;"
+}
+
+regression_assign_arrow_functions: {
+    input: {
+        oninstall = e => false;
+        oninstall = () => false;
+    }
+    expect: {
+        oninstall=e=>false;
+        oninstall=()=>false;
+    }
+}
+
+destructuring_arguments_1: {
+    input: {
+        (function ( a ) { });
+        (function ( [ a ] ) { });
+        (function ( [ a, b ] ) { });
+        (function ( [ [ a ] ] ) { });
+        (function ( [ [ a, b ] ] ) { });
+        (function ( [ a, [ b ] ] ) { });
+        (function ( [ [ b ], a ] ) { });
+
+        (function ( { a } ) { });
+        (function ( { a, b } ) { });
+
+        (function ( [ { a } ] ) { });
+        (function ( [ { a, b } ] ) { });
+        (function ( [ a, { b } ] ) { });
+        (function ( [ { b }, a ] ) { });
+
+        ( [ a ] ) => { };
+        ( [ a, b ] ) => { };
+
+        ( { a } ) => { };
+        ( { a, b, c, d, e } ) => { };
+
+        ( [ a ] ) => b;
+        ( [ a, b ] ) => c;
+
+        ( { a } ) => b;
+        ( { a, b } ) => c;
+    }
+    expect: {
+        (function(a){});
+        (function([a]){});
+        (function([a,b]){});
+        (function([[a]]){});
+        (function([[a,b]]){});
+        (function([a,[b]]){});
+        (function([[b],a]){});
+
+        (function({a}){});
+        (function({a,b}){});
+
+        (function([{a}]){});
+        (function([{a,b}]){});
+        (function([a,{b}]){});
+        (function([{b},a]){});
+
+        ([a])=>{};
+        ([a,b])=>{};
+
+        ({a})=>{};
+        ({a,b,c,d,e})=>{};
+
+        ([a])=>b;
+        ([a,b])=>c;
+
+        ({a})=>b;
+        ({a,b})=>c;
+    }
+}
+
+destructuring_arguments_2: {
+    input: {
+        (function([]) {});
+        (function({}) {});
+        (function([,,,,,]) {});
+        (function ([a, {b: c}]) {});
+        (function ([...args]) {});
+        (function ({x,}) {});
+        class a { *method({ [thrower()]: x } = {}) {}};
+        (function(a, b, c, d, [{e: [...f]}]){})(1, 2, 3, 4, [{e: [1, 2, 3]}]);
+    }
+    expect: {
+        (function([]) {});
+        (function({}) {});
+        (function([,,,,,]) {});
+        (function ([a, {b: c}]) {});
+        (function ([...args]) {});
+        (function ({x,}) {});
+        class a { *method({ [thrower()]: x } = {}) {}};
+        (function(a, b, c, d, [{e: [...f]}]){})(1, 2, 3, 4, [{e: [1, 2, 3]}]);
+    }
+}
+
+destructuring_arguments_3: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        function fn3({x: {y: {z: {} = 42}}}) {}
+        const { cover = (function () {}), xCover = (0, function() {})  } = {};
+        let { cover = (function () {}), xCover = (0, function() {})  } = {};
+        var { cover = (function () {}), xCover = (0, function() {})  } = {};
+    }
+    expect_exact: "function fn3({x:{y:{z:{}=42}}}){}const{cover=function(){},xCover=(0,function(){})}={};let{cover=function(){},xCover=(0,function(){})}={};var{cover=function(){},xCover=(0,function(){})}={};"
+}
+
+default_arguments: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        function x(a = 6) { }
+        function x(a = (6 + 5)) { }
+        function x({ foo } = {}, [ bar ] = [ 1 ]) { }
+    }
+    expect_exact: "function x(a=6){}function x(a=6+5){}function x({foo}={},[bar]=[1]){}"
+}
+
+default_values_in_destructurings: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        function x({a=(4), b}) {}
+        function x([b, c=(12)]) {}
+        var { x = (6), y } = x;
+        var [ x, y = (6) ] = x;
+    }
+    expect_exact: "function x({a=4,b}){}function x([b,c=12]){}var{x=6,y}=x;var[x,y=6]=x;"
+}
+
+accept_duplicated_parameters_in_non_strict_without_spread_or_default_assignment: {
+    input: {
+        function a(b, b){}
+        function b({c: test, c: test}){}
+    }
+    expect: {
+        function a(b, b){}
+        function b({c: test, c: test}){}
+    }
+}

test/compress/properties.js

@@ -12,7 +12,8 @@ keep_properties: {
 
 dot_properties: {
     options = {
-        properties: true
+        properties: true,
+        screw_ie8: false
     };
     input: {
         a["foo"] = "bar";
@@ -20,13 +21,15 @@ dot_properties: {
         a["*"] = "asterisk";
         a["\u0EB3"] = "unicode";
         a[""] = "whitespace";
+        a["1_1"] = "foo";
     }
     expect: {
         a.foo = "bar";
         a["if"] = "if";
         a["*"] = "asterisk";
-        a.\u0EB3 = "unicode";
+        a["\u0EB3"] = "unicode";
         a[""] = "whitespace";
+        a["1_1"] = "foo";
     }
 }
 
@@ -46,7 +49,510 @@ dot_properties_es5: {
         a.foo = "bar";
         a.if = "if";
         a["*"] = "asterisk";
-        a.\u0EB3 = "unicode";
+        a["\u0EB3"] = "unicode";
         a[""] = "whitespace";
     }
 }
+
+sub_properties: {
+    options = {
+        evaluate: true,
+        properties: true
+    };
+    input: {
+        a[0] = 0;
+        a["0"] = 1;
+        a[3.14] = 2;
+        a["3" + ".14"] = 3;
+        a["i" + "f"] = 4;
+        a["foo" + " bar"] = 5;
+        a[0 / 0] = 6;
+        a[null] = 7;
+        a[undefined] = 8;
+    }
+    expect: {
+        a[0] = 0;
+        a[0] = 1;
+        a[3.14] = 2;
+        a[3.14] = 3;
+        a.if = 4;
+        a["foo bar"] = 5;
+        a[NaN] = 6;
+        a[null] = 7;
+        a[void 0] = 8;
+    }
+}
+
+evaluate_array_length: {
+    options = {
+        properties: true,
+        unsafe: true,
+        evaluate: true
+    };
+    input: {
+        a = [1, 2, 3].length;
+        a = [1, 2, 3].join()["len" + "gth"];
+        a = [1, 2, b].length;
+        a = [1, 2, 3].join(b).length;
+    }
+    expect: {
+        a = 3;
+        a = 5;
+        a = [1, 2, b].length;
+        a = [1, 2, 3].join(b).length;
+    }
+}
+
+evaluate_string_length: {
+    options = {
+        properties: true,
+        unsafe: true,
+        evaluate: true
+    };
+    input: {
+        a = "foo".length;
+        a = ("foo" + "bar")["len" + "gth"];
+        a = b.length;
+        a = ("foo" + b).length;
+    }
+    expect: {
+        a = 3;
+        a = 6;
+        a = b.length;
+        a = ("foo" + b).length;
+    }
+}
+
+mangle_properties: {
+    mangle_props = {
+        ignore_quoted: false
+    };
+    input: {
+        a["foo"] = "bar";
+        a.color = "red";
+        x = {"bar": 10};
+        a.run(x.bar, a.foo);
+        a['run']({color: "blue", foo: "baz"});
+    }
+    expect: {
+        a["a"] = "bar";
+        a.b = "red";
+        x = {c: 10};
+        a.d(x.c, a.a);
+        a['d']({b: "blue", a: "baz"});
+    }
+}
+
+mangle_unquoted_properties: {
+    options = {
+        properties: false
+    }
+    mangle_props = {
+        ignore_quoted: true,
+        reserved: []
+    }
+    beautify = {
+        beautify: false,
+        quote_style: 3,
+        keep_quoted_props: true,
+    }
+    input: {
+        a.top = 1;
+        function f1() {
+            a["foo"] = "bar";
+            a.color = "red";
+            a.stuff = 2;
+            x = {"bar": 10, size: 7};
+            a.size = 9;
+        }
+        function f2() {
+            a.foo = "bar";
+            a['color'] = "red";
+            x = {bar: 10, size: 7};
+            a.size = 9;
+            a.stuff = 3;
+        }
+    }
+    expect: {
+        a.a = 1;
+        function f1() {
+            a["foo"] = "bar";
+            a.color = "red";
+            a.b = 2;
+            x = {"bar": 10, c: 7};
+            a.c = 9;
+        }
+        function f2() {
+            a.foo = "bar";
+            a['color'] = "red";
+            x = {bar: 10, c: 7};
+            a.c = 9;
+            a.b = 3;
+        }
+    }
+}
+
+mangle_debug: {
+    mangle_props = {
+        debug: ""
+    };
+    input: {
+        a.foo = "bar";
+        x = { baz: "ban" };
+    }
+    expect: {
+        a._$foo$_ = "bar";
+        x = { _$baz$_: "ban" };
+    }
+}
+
+mangle_debug_true: {
+    mangle_props = {
+        debug: true
+    };
+    input: {
+        a.foo = "bar";
+        x = { baz: "ban" };
+    }
+    expect: {
+        a._$foo$_ = "bar";
+        x = { _$baz$_: "ban" };
+    }
+}
+
+mangle_debug_suffix: {
+    mangle_props = {
+        debug: "XYZ"
+    };
+    input: {
+        a.foo = "bar";
+        x = { baz: "ban" };
+    }
+    expect: {
+        a._$foo$XYZ_ = "bar";
+        x = { _$baz$XYZ_: "ban" };
+    }
+}
+
+mangle_debug_suffix_ignore_quoted: {
+    options = {
+        properties: false
+    }
+    mangle_props = {
+        ignore_quoted: true,
+        debug: "XYZ",
+        reserved: []
+    }
+    beautify = {
+        beautify: false,
+        quote_style: 3,
+        keep_quoted_props: true,
+    }
+    input: {
+        a.top = 1;
+        function f1() {
+            a["foo"] = "bar";
+            a.color = "red";
+            a.stuff = 2;
+            x = {"bar": 10, size: 7};
+            a.size = 9;
+        }
+        function f2() {
+            a.foo = "bar";
+            a['color'] = "red";
+            x = {bar: 10, size: 7};
+            a.size = 9;
+            a.stuff = 3;
+        }
+    }
+    expect: {
+        a._$top$XYZ_ = 1;
+        function f1() {
+            a["foo"] = "bar";
+            a.color = "red";
+            a._$stuff$XYZ_ = 2;
+            x = {"bar": 10, _$size$XYZ_: 7};
+            a._$size$XYZ_ = 9;
+        }
+        function f2() {
+            a.foo = "bar";
+            a['color'] = "red";
+            x = {bar: 10, _$size$XYZ_: 7};
+            a._$size$XYZ_ = 9;
+            a._$stuff$XYZ_ = 3;
+        }
+    }
+}
+
+first_256_chars_as_properties: {
+    beautify = {
+        ascii_only: true,
+    }
+    input: {
+        // Note: some of these unicode character keys are not visible on github.com
+        var o = {
+            "\0":0,"
":1,"":2,"":3,"":4,"":5,"":6,"":7,"\b":8,
+            "\t":9,"\n":10,"\v":11,"\f":12,"\r":13,"":14,"":15,"":16,"":17,
+            "":18,"":19,"":20,"":21,"":22,"":23,"":24,"":25,"":26,
+            "":27,"":28,"":29,"":30,"":31," ":32,"!":33,'"':34,"#":35,
+            $:36,"%":37,"&":38,"'":39,"(":40,")":41,"*":42,"+":43,",":44,
+            "-":45,".":46,"/":47,"0":48,"1":49,"2":50,"3":51,"4":52,"5":53,"6":54,"7":55,
+            "8":56,"9":57,":":58,";":59,"<":60,"=":61,">":62,"?":63,"@":64,A:65,
+            B:66,C:67,D:68,E:69,F:70,G:71,H:72,I:73,J:74,K:75,L:76,M:77,N:78,
+            O:79,P:80,Q:81,R:82,S:83,T:84,U:85,V:86,W:87,X:88,Y:89,Z:90,"[":91,
+            "\\":92,"]":93,"^":94,_:95,"`":96,a:97,b:98,c:99,d:100,e:101,
+            f:102,g:103,h:104,i:105,j:106,k:107,l:108,m:109,n:110,o:111,p:112,
+            q:113,r:114,s:115,t:116,u:117,v:118,w:119,x:120,y:121,z:122,"{":123,
+            "|":124,"}":125,"~":126,"":127,"€":128,"":129,"‚":130,"ƒ":131,
+            "„":132,"…":133,"†":134,"‡":135,"ˆ":136,"‰":137,"Š":138,"‹":139,
+            "Œ":140,"":141,"Ž":142,"":143,"":144,"‘":145,"’":146,"“":147,
+            "”":148,"•":149,"–":150,"—":151,"˜":152,"™":153,"š":154,"›":155,
+            "œ":156,"":157,"ž":158,"Ÿ":159," ":160,"¡":161,"¢":162,"£":163,
+            "¤":164,"¥":165,"¦":166,"§":167,"¨":168,"©":169,"ª":170,"«":171,
+            "¬":172,"­":173,"®":174,"¯":175,"°":176,"±":177,"²":178,"³":179,
+            "´":180,"µ":181,"¶":182,"·":183,"¸":184,"¹":185,"º":186,"»":187,
+            "¼":188,"½":189,"¾":190,"¿":191,"À":192,"Á":193,"Â":194,"Ã":195,
+            "Ä":196,"Å":197,"Æ":198,"Ç":199,"È":200,"É":201,"Ê":202,"Ë":203,
+            "Ì":204,"Í":205,"Î":206,"Ï":207,"Ð":208,"Ñ":209,"Ò":210,"Ó":211,
+            "Ô":212,"Õ":213,"Ö":214,"×":215,"Ø":216,"Ù":217,"Ú":218,"Û":219,
+            "Ü":220,"Ý":221,"Þ":222,"ß":223,"à":224,"á":225,"â":226,"ã":227,
+            "ä":228,"å":229,"æ":230,"ç":231,"è":232,"é":233,"ê":234,"ë":235,
+            "ì":236,"í":237,"î":238,"ï":239,"ð":240,"ñ":241,"ò":242,"ó":243,
+            "ô":244,"õ":245,"ö":246,"÷":247,"ø":248,"ù":249,"ú":250,"û":251,
+            "ü":252,"ý":253,"þ":254,"ÿ":255
+        };
+    }
+    expect: {
+        var o = {
+            "\0":0,"\x01":1,"\x02":2,"\x03":3,"\x04":4,"\x05":5,"\x06":6,
+            "\x07":7,"\b":8,"\t":9,"\n":10,"\v":11,"\f":12,"\r":13,"\x0e":14,
+            "\x0f":15,"\x10":16,"\x11":17,"\x12":18,"\x13":19,"\x14":20,"\x15":21,
+            "\x16":22,"\x17":23,"\x18":24,"\x19":25,"\x1a":26,"\x1b":27,"\x1c":28,
+            "\x1d":29,"\x1e":30,"\x1f":31," ":32,"!":33,'"':34,"#":35,$:36,
+            "%":37,"&":38,"'":39,"(":40,")":41,"*":42,"+":43,",":44,"-":45,
+            ".":46,"/":47,0:48,1:49,2:50,3:51,4:52,5:53,6:54,7:55,8:56,9:57,
+            ":":58,";":59,"<":60,"=":61,">":62,"?":63,"@":64,A:65,B:66,C:67,
+            D:68,E:69,F:70,G:71,H:72,I:73,J:74,K:75,L:76,M:77,N:78,O:79,P:80,
+            Q:81,R:82,S:83,T:84,U:85,V:86,W:87,X:88,Y:89,Z:90,"[":91,"\\":92,
+            "]":93,"^":94,_:95,"`":96,a:97,b:98,c:99,d:100,e:101,f:102,g:103,
+            h:104,i:105,j:106,k:107,l:108,m:109,n:110,o:111,p:112,q:113,r:114,
+            s:115,t:116,u:117,v:118,w:119,x:120,y:121,z:122,"{":123,"|":124,
+            "}":125,"~":126,"\x7f":127,"\x80":128,"\x81":129,"\x82":130,"\x83":131,
+            "\x84":132,"\x85":133,"\x86":134,"\x87":135,"\x88":136,"\x89":137,
+            "\x8a":138,"\x8b":139,"\x8c":140,"\x8d":141,"\x8e":142,"\x8f":143,
+            "\x90":144,"\x91":145,"\x92":146,"\x93":147,"\x94":148,"\x95":149,
+            "\x96":150,"\x97":151,"\x98":152,"\x99":153,"\x9a":154,"\x9b":155,
+            "\x9c":156,"\x9d":157,"\x9e":158,"\x9f":159,"\xa0":160,"\xa1":161,
+            "\xa2":162,"\xa3":163,"\xa4":164,"\xa5":165,"\xa6":166,"\xa7":167,
+            "\xa8":168,"\xa9":169,"\xaa":170,"\xab":171,"\xac":172,"\xad":173,
+            "\xae":174,"\xaf":175,"\xb0":176,"\xb1":177,"\xb2":178,"\xb3":179,
+            "\xb4":180,"\xb5":181,"\xb6":182,"\xb7":183,"\xb8":184,"\xb9":185,
+            "\xba":186,"\xbb":187,"\xbc":188,"\xbd":189,"\xbe":190,"\xbf":191,
+            "\xc0":192,"\xc1":193,"\xc2":194,"\xc3":195,"\xc4":196,"\xc5":197,
+            "\xc6":198,"\xc7":199,"\xc8":200,"\xc9":201,"\xca":202,"\xcb":203,
+            "\xcc":204,"\xcd":205,"\xce":206,"\xcf":207,"\xd0":208,"\xd1":209,
+            "\xd2":210,"\xd3":211,"\xd4":212,"\xd5":213,"\xd6":214,"\xd7":215,
+            "\xd8":216,"\xd9":217,"\xda":218,"\xdb":219,"\xdc":220,"\xdd":221,
+            "\xde":222,"\xdf":223,"\xe0":224,"\xe1":225,"\xe2":226,"\xe3":227,
+            "\xe4":228,"\xe5":229,"\xe6":230,"\xe7":231,"\xe8":232,"\xe9":233,
+            "\xea":234,"\xeb":235,"\xec":236,"\xed":237,"\xee":238,"\xef":239,
+            "\xf0":240,"\xf1":241,"\xf2":242,"\xf3":243,"\xf4":244,"\xf5":245,
+            "\xf6":246,"\xf7":247,"\xf8":248,"\xf9":249,"\xfa":250,"\xfb":251,
+            "\xfc":252,"\xfd":253,"\xfe":254,"\xff":255
+        };
+    }
+}
+
+first_256_unicode_chars_as_properties: {
+    input: {
+        var o = {
+            "\u0000":   0, "\u0001":   1, "\u0002":   2, "\u0003":   3, "\u0004":   4, "\u0005":   5,
+            "\u0006":   6, "\u0007":   7, "\u0008":   8, "\u0009":   9, "\u000A":  10, "\u000B":  11,
+            "\u000C":  12, "\u000D":  13, "\u000E":  14, "\u000F":  15, "\u0010":  16, "\u0011":  17,
+            "\u0012":  18, "\u0013":  19, "\u0014":  20, "\u0015":  21, "\u0016":  22, "\u0017":  23,
+            "\u0018":  24, "\u0019":  25, "\u001A":  26, "\u001B":  27, "\u001C":  28, "\u001D":  29,
+            "\u001E":  30, "\u001F":  31, "\u0020":  32, "\u0021":  33, "\u0022":  34, "\u0023":  35,
+            "\u0024":  36, "\u0025":  37, "\u0026":  38, "\u0027":  39, "\u0028":  40, "\u0029":  41,
+            "\u002A":  42, "\u002B":  43, "\u002C":  44, "\u002D":  45, "\u002E":  46, "\u002F":  47,
+            "\u0030":  48, "\u0031":  49, "\u0032":  50, "\u0033":  51, "\u0034":  52, "\u0035":  53,
+            "\u0036":  54, "\u0037":  55, "\u0038":  56, "\u0039":  57, "\u003A":  58, "\u003B":  59,
+            "\u003C":  60, "\u003D":  61, "\u003E":  62, "\u003F":  63, "\u0040":  64, "\u0041":  65,
+            "\u0042":  66, "\u0043":  67, "\u0044":  68, "\u0045":  69, "\u0046":  70, "\u0047":  71,
+            "\u0048":  72, "\u0049":  73, "\u004A":  74, "\u004B":  75, "\u004C":  76, "\u004D":  77,
+            "\u004E":  78, "\u004F":  79, "\u0050":  80, "\u0051":  81, "\u0052":  82, "\u0053":  83,
+            "\u0054":  84, "\u0055":  85, "\u0056":  86, "\u0057":  87, "\u0058":  88, "\u0059":  89,
+            "\u005A":  90, "\u005B":  91, "\u005C":  92, "\u005D":  93, "\u005E":  94, "\u005F":  95,
+            "\u0060":  96, "\u0061":  97, "\u0062":  98, "\u0063":  99, "\u0064": 100, "\u0065": 101,
+            "\u0066": 102, "\u0067": 103, "\u0068": 104, "\u0069": 105, "\u006A": 106, "\u006B": 107,
+            "\u006C": 108, "\u006D": 109, "\u006E": 110, "\u006F": 111, "\u0070": 112, "\u0071": 113,
+            "\u0072": 114, "\u0073": 115, "\u0074": 116, "\u0075": 117, "\u0076": 118, "\u0077": 119,
+            "\u0078": 120, "\u0079": 121, "\u007A": 122, "\u007B": 123, "\u007C": 124, "\u007D": 125,
+            "\u007E": 126, "\u007F": 127, "\u0080": 128, "\u0081": 129, "\u0082": 130, "\u0083": 131,
+            "\u0084": 132, "\u0085": 133, "\u0086": 134, "\u0087": 135, "\u0088": 136, "\u0089": 137,
+            "\u008A": 138, "\u008B": 139, "\u008C": 140, "\u008D": 141, "\u008E": 142, "\u008F": 143,
+            "\u0090": 144, "\u0091": 145, "\u0092": 146, "\u0093": 147, "\u0094": 148, "\u0095": 149,
+            "\u0096": 150, "\u0097": 151, "\u0098": 152, "\u0099": 153, "\u009A": 154, "\u009B": 155,
+            "\u009C": 156, "\u009D": 157, "\u009E": 158, "\u009F": 159, "\u00A0": 160, "\u00A1": 161,
+            "\u00A2": 162, "\u00A3": 163, "\u00A4": 164, "\u00A5": 165, "\u00A6": 166, "\u00A7": 167,
+            "\u00A8": 168, "\u00A9": 169, "\u00AA": 170, "\u00AB": 171, "\u00AC": 172, "\u00AD": 173,
+            "\u00AE": 174, "\u00AF": 175, "\u00B0": 176, "\u00B1": 177, "\u00B2": 178, "\u00B3": 179,
+            "\u00B4": 180, "\u00B5": 181, "\u00B6": 182, "\u00B7": 183, "\u00B8": 184, "\u00B9": 185,
+            "\u00BA": 186, "\u00BB": 187, "\u00BC": 188, "\u00BD": 189, "\u00BE": 190, "\u00BF": 191,
+            "\u00C0": 192, "\u00C1": 193, "\u00C2": 194, "\u00C3": 195, "\u00C4": 196, "\u00C5": 197,
+            "\u00C6": 198, "\u00C7": 199, "\u00C8": 200, "\u00C9": 201, "\u00CA": 202, "\u00CB": 203,
+            "\u00CC": 204, "\u00CD": 205, "\u00CE": 206, "\u00CF": 207, "\u00D0": 208, "\u00D1": 209,
+            "\u00D2": 210, "\u00D3": 211, "\u00D4": 212, "\u00D5": 213, "\u00D6": 214, "\u00D7": 215,
+            "\u00D8": 216, "\u00D9": 217, "\u00DA": 218, "\u00DB": 219, "\u00DC": 220, "\u00DD": 221,
+            "\u00DE": 222, "\u00DF": 223, "\u00E0": 224, "\u00E1": 225, "\u00E2": 226, "\u00E3": 227,
+            "\u00E4": 228, "\u00E5": 229, "\u00E6": 230, "\u00E7": 231, "\u00E8": 232, "\u00E9": 233,
+            "\u00EA": 234, "\u00EB": 235, "\u00EC": 236, "\u00ED": 237, "\u00EE": 238, "\u00EF": 239,
+            "\u00F0": 240, "\u00F1": 241, "\u00F2": 242, "\u00F3": 243, "\u00F4": 244, "\u00F5": 245,
+            "\u00F6": 246, "\u00F7": 247, "\u00F8": 248, "\u00F9": 249, "\u00FA": 250, "\u00FB": 251,
+            "\u00FC": 252, "\u00FD": 253, "\u00FE": 254, "\u00FF": 255
+        };
+    }
+    expect: {
+        var o = {
+            "\0":0,"\x01":1,"\x02":2,"\x03":3,"\x04":4,"\x05":5,"\x06":6,
+            "\x07":7,"\b":8,"\t":9,"\n":10,"\v":11,"\f":12,"\r":13,"\x0e":14,
+            "\x0f":15,"\x10":16,"\x11":17,"\x12":18,"\x13":19,"\x14":20,"\x15":21,
+            "\x16":22,"\x17":23,"\x18":24,"\x19":25,"\x1a":26,"\x1b":27,"\x1c":28,
+            "\x1d":29,"\x1e":30,"\x1f":31," ":32,"!":33,'"':34,"#":35,$:36,
+            "%":37,"&":38,"'":39,"(":40,")":41,"*":42,"+":43,",":44,"-":45,
+            ".":46,"/":47,0:48,1:49,2:50,3:51,4:52,5:53,6:54,7:55,8:56,9:57,
+            ":":58,";":59,"<":60,"=":61,">":62,"?":63,"@":64,A:65,B:66,C:67,
+            D:68,E:69,F:70,G:71,H:72,I:73,J:74,K:75,L:76,M:77,N:78,O:79,P:80,
+            Q:81,R:82,S:83,T:84,U:85,V:86,W:87,X:88,Y:89,Z:90,"[":91,"\\":92,
+            "]":93,"^":94,_:95,"`":96,a:97,b:98,c:99,d:100,e:101,f:102,g:103,
+            h:104,i:105,j:106,k:107,l:108,m:109,n:110,o:111,p:112,q:113,r:114,
+            s:115,t:116,u:117,v:118,w:119,x:120,y:121,z:122,"{":123,"|":124,
+            "}":125,"~":126,"\x7f":127,"\x80":128,"\x81":129,"\x82":130,"\x83":131,
+            "\x84":132,"\x85":133,"\x86":134,"\x87":135,"\x88":136,"\x89":137,
+            "\x8a":138,"\x8b":139,"\x8c":140,"\x8d":141,"\x8e":142,"\x8f":143,
+            "\x90":144,"\x91":145,"\x92":146,"\x93":147,"\x94":148,"\x95":149,
+            "\x96":150,"\x97":151,"\x98":152,"\x99":153,"\x9a":154,"\x9b":155,
+            "\x9c":156,"\x9d":157,"\x9e":158,"\x9f":159,"\xa0":160,"\xa1":161,
+            "\xa2":162,"\xa3":163,"\xa4":164,"\xa5":165,"\xa6":166,"\xa7":167,
+            "\xa8":168,"\xa9":169,"\xaa":170,"\xab":171,"\xac":172,"\xad":173,
+            "\xae":174,"\xaf":175,"\xb0":176,"\xb1":177,"\xb2":178,"\xb3":179,
+            "\xb4":180,"\xb5":181,"\xb6":182,"\xb7":183,"\xb8":184,"\xb9":185,
+            "\xba":186,"\xbb":187,"\xbc":188,"\xbd":189,"\xbe":190,"\xbf":191,
+            "\xc0":192,"\xc1":193,"\xc2":194,"\xc3":195,"\xc4":196,"\xc5":197,
+            "\xc6":198,"\xc7":199,"\xc8":200,"\xc9":201,"\xca":202,"\xcb":203,
+            "\xcc":204,"\xcd":205,"\xce":206,"\xcf":207,"\xd0":208,"\xd1":209,
+            "\xd2":210,"\xd3":211,"\xd4":212,"\xd5":213,"\xd6":214,"\xd7":215,
+            "\xd8":216,"\xd9":217,"\xda":218,"\xdb":219,"\xdc":220,"\xdd":221,
+            "\xde":222,"\xdf":223,"\xe0":224,"\xe1":225,"\xe2":226,"\xe3":227,
+            "\xe4":228,"\xe5":229,"\xe6":230,"\xe7":231,"\xe8":232,"\xe9":233,
+            "\xea":234,"\xeb":235,"\xec":236,"\xed":237,"\xee":238,"\xef":239,
+            "\xf0":240,"\xf1":241,"\xf2":242,"\xf3":243,"\xf4":244,"\xf5":245,
+            "\xf6":246,"\xf7":247,"\xf8":248,"\xf9":249,"\xfa":250,"\xfb":251,
+            "\xfc":252,"\xfd":253,"\xfe":254,"\xff":255
+        };
+    }
+}
+
+first_256_hex_chars_as_properties: {
+    input: {
+        var o = {
+            "\x00":   0, "\x01":   1, "\x02":   2, "\x03":   3, "\x04":   4, "\x05":   5,
+            "\x06":   6, "\x07":   7, "\x08":   8, "\x09":   9, "\x0A":  10, "\x0B":  11,
+            "\x0C":  12, "\x0D":  13, "\x0E":  14, "\x0F":  15, "\x10":  16, "\x11":  17,
+            "\x12":  18, "\x13":  19, "\x14":  20, "\x15":  21, "\x16":  22, "\x17":  23,
+            "\x18":  24, "\x19":  25, "\x1A":  26, "\x1B":  27, "\x1C":  28, "\x1D":  29,
+            "\x1E":  30, "\x1F":  31, "\x20":  32, "\x21":  33, "\x22":  34, "\x23":  35,
+            "\x24":  36, "\x25":  37, "\x26":  38, "\x27":  39, "\x28":  40, "\x29":  41,
+            "\x2A":  42, "\x2B":  43, "\x2C":  44, "\x2D":  45, "\x2E":  46, "\x2F":  47,
+            "\x30":  48, "\x31":  49, "\x32":  50, "\x33":  51, "\x34":  52, "\x35":  53,
+            "\x36":  54, "\x37":  55, "\x38":  56, "\x39":  57, "\x3A":  58, "\x3B":  59,
+            "\x3C":  60, "\x3D":  61, "\x3E":  62, "\x3F":  63, "\x40":  64, "\x41":  65,
+            "\x42":  66, "\x43":  67, "\x44":  68, "\x45":  69, "\x46":  70, "\x47":  71,
+            "\x48":  72, "\x49":  73, "\x4A":  74, "\x4B":  75, "\x4C":  76, "\x4D":  77,
+            "\x4E":  78, "\x4F":  79, "\x50":  80, "\x51":  81, "\x52":  82, "\x53":  83,
+            "\x54":  84, "\x55":  85, "\x56":  86, "\x57":  87, "\x58":  88, "\x59":  89,
+            "\x5A":  90, "\x5B":  91, "\x5C":  92, "\x5D":  93, "\x5E":  94, "\x5F":  95,
+            "\x60":  96, "\x61":  97, "\x62":  98, "\x63":  99, "\x64": 100, "\x65": 101,
+            "\x66": 102, "\x67": 103, "\x68": 104, "\x69": 105, "\x6A": 106, "\x6B": 107,
+            "\x6C": 108, "\x6D": 109, "\x6E": 110, "\x6F": 111, "\x70": 112, "\x71": 113,
+            "\x72": 114, "\x73": 115, "\x74": 116, "\x75": 117, "\x76": 118, "\x77": 119,
+            "\x78": 120, "\x79": 121, "\x7A": 122, "\x7B": 123, "\x7C": 124, "\x7D": 125,
+            "\x7E": 126, "\x7F": 127, "\x80": 128, "\x81": 129, "\x82": 130, "\x83": 131,
+            "\x84": 132, "\x85": 133, "\x86": 134, "\x87": 135, "\x88": 136, "\x89": 137,
+            "\x8A": 138, "\x8B": 139, "\x8C": 140, "\x8D": 141, "\x8E": 142, "\x8F": 143,
+            "\x90": 144, "\x91": 145, "\x92": 146, "\x93": 147, "\x94": 148, "\x95": 149,
+            "\x96": 150, "\x97": 151, "\x98": 152, "\x99": 153, "\x9A": 154, "\x9B": 155,
+            "\x9C": 156, "\x9D": 157, "\x9E": 158, "\x9F": 159, "\xA0": 160, "\xA1": 161,
+            "\xA2": 162, "\xA3": 163, "\xA4": 164, "\xA5": 165, "\xA6": 166, "\xA7": 167,
+            "\xA8": 168, "\xA9": 169, "\xAA": 170, "\xAB": 171, "\xAC": 172, "\xAD": 173,
+            "\xAE": 174, "\xAF": 175, "\xB0": 176, "\xB1": 177, "\xB2": 178, "\xB3": 179,
+            "\xB4": 180, "\xB5": 181, "\xB6": 182, "\xB7": 183, "\xB8": 184, "\xB9": 185,
+            "\xBA": 186, "\xBB": 187, "\xBC": 188, "\xBD": 189, "\xBE": 190, "\xBF": 191,
+            "\xC0": 192, "\xC1": 193, "\xC2": 194, "\xC3": 195, "\xC4": 196, "\xC5": 197,
+            "\xC6": 198, "\xC7": 199, "\xC8": 200, "\xC9": 201, "\xCA": 202, "\xCB": 203,
+            "\xCC": 204, "\xCD": 205, "\xCE": 206, "\xCF": 207, "\xD0": 208, "\xD1": 209,
+            "\xD2": 210, "\xD3": 211, "\xD4": 212, "\xD5": 213, "\xD6": 214, "\xD7": 215,
+            "\xD8": 216, "\xD9": 217, "\xDA": 218, "\xDB": 219, "\xDC": 220, "\xDD": 221,
+            "\xDE": 222, "\xDF": 223, "\xE0": 224, "\xE1": 225, "\xE2": 226, "\xE3": 227,
+            "\xE4": 228, "\xE5": 229, "\xE6": 230, "\xE7": 231, "\xE8": 232, "\xE9": 233,
+            "\xEA": 234, "\xEB": 235, "\xEC": 236, "\xED": 237, "\xEE": 238, "\xEF": 239,
+            "\xF0": 240, "\xF1": 241, "\xF2": 242, "\xF3": 243, "\xF4": 244, "\xF5": 245,
+            "\xF6": 246, "\xF7": 247, "\xF8": 248, "\xF9": 249, "\xFA": 250, "\xFB": 251,
+            "\xFC": 252, "\xFD": 253, "\xFE": 254, "\xFF": 255
+        };
+    }
+    expect: {
+        var o = {
+            "\0":0,"\x01":1,"\x02":2,"\x03":3,"\x04":4,"\x05":5,"\x06":6,
+            "\x07":7,"\b":8,"\t":9,"\n":10,"\v":11,"\f":12,"\r":13,"\x0e":14,
+            "\x0f":15,"\x10":16,"\x11":17,"\x12":18,"\x13":19,"\x14":20,"\x15":21,
+            "\x16":22,"\x17":23,"\x18":24,"\x19":25,"\x1a":26,"\x1b":27,"\x1c":28,
+            "\x1d":29,"\x1e":30,"\x1f":31," ":32,"!":33,'"':34,"#":35,$:36,
+            "%":37,"&":38,"'":39,"(":40,")":41,"*":42,"+":43,",":44,"-":45,
+            ".":46,"/":47,0:48,1:49,2:50,3:51,4:52,5:53,6:54,7:55,8:56,9:57,
+            ":":58,";":59,"<":60,"=":61,">":62,"?":63,"@":64,A:65,B:66,C:67,
+            D:68,E:69,F:70,G:71,H:72,I:73,J:74,K:75,L:76,M:77,N:78,O:79,P:80,
+            Q:81,R:82,S:83,T:84,U:85,V:86,W:87,X:88,Y:89,Z:90,"[":91,"\\":92,
+            "]":93,"^":94,_:95,"`":96,a:97,b:98,c:99,d:100,e:101,f:102,g:103,
+            h:104,i:105,j:106,k:107,l:108,m:109,n:110,o:111,p:112,q:113,r:114,
+            s:115,t:116,u:117,v:118,w:119,x:120,y:121,z:122,"{":123,"|":124,
+            "}":125,"~":126,"\x7f":127,"\x80":128,"\x81":129,"\x82":130,"\x83":131,
+            "\x84":132,"\x85":133,"\x86":134,"\x87":135,"\x88":136,"\x89":137,
+            "\x8a":138,"\x8b":139,"\x8c":140,"\x8d":141,"\x8e":142,"\x8f":143,
+            "\x90":144,"\x91":145,"\x92":146,"\x93":147,"\x94":148,"\x95":149,
+            "\x96":150,"\x97":151,"\x98":152,"\x99":153,"\x9a":154,"\x9b":155,
+            "\x9c":156,"\x9d":157,"\x9e":158,"\x9f":159,"\xa0":160,"\xa1":161,
+            "\xa2":162,"\xa3":163,"\xa4":164,"\xa5":165,"\xa6":166,"\xa7":167,
+            "\xa8":168,"\xa9":169,"\xaa":170,"\xab":171,"\xac":172,"\xad":173,
+            "\xae":174,"\xaf":175,"\xb0":176,"\xb1":177,"\xb2":178,"\xb3":179,
+            "\xb4":180,"\xb5":181,"\xb6":182,"\xb7":183,"\xb8":184,"\xb9":185,
+            "\xba":186,"\xbb":187,"\xbc":188,"\xbd":189,"\xbe":190,"\xbf":191,
+            "\xc0":192,"\xc1":193,"\xc2":194,"\xc3":195,"\xc4":196,"\xc5":197,
+            "\xc6":198,"\xc7":199,"\xc8":200,"\xc9":201,"\xca":202,"\xcb":203,
+            "\xcc":204,"\xcd":205,"\xce":206,"\xcf":207,"\xd0":208,"\xd1":209,
+            "\xd2":210,"\xd3":211,"\xd4":212,"\xd5":213,"\xd6":214,"\xd7":215,
+            "\xd8":216,"\xd9":217,"\xda":218,"\xdb":219,"\xdc":220,"\xdd":221,
+            "\xde":222,"\xdf":223,"\xe0":224,"\xe1":225,"\xe2":226,"\xe3":227,
+            "\xe4":228,"\xe5":229,"\xe6":230,"\xe7":231,"\xe8":232,"\xe9":233,
+            "\xea":234,"\xeb":235,"\xec":236,"\xed":237,"\xee":238,"\xef":239,
+            "\xf0":240,"\xf1":241,"\xf2":242,"\xf3":243,"\xf4":244,"\xf5":245,
+            "\xf6":246,"\xf7":247,"\xf8":248,"\xf9":249,"\xfa":250,"\xfb":251,
+            "\xfc":252,"\xfd":253,"\xfe":254,"\xff":255
+        };
+    }
+}
+
+native_prototype: {
+    options = {
+        unsafe_proto: true,
+    }
+    input: {
+        Array.prototype.splice.apply(a, [1, 2, b, c]);
+        Object.prototype.hasOwnProperty.call(d, "foo");
+        String.prototype.indexOf.call(e, "bar");
+    }
+    expect: {
+        [].splice.apply(a, [1, 2, b, c]);
+        ({}).hasOwnProperty.call(d, "foo");
+        "".indexOf.call(e, "bar");
+    }
+}

test/compress/pure_funcs.js

@@ -0,0 +1,295 @@
+array: {
+    options = {
+        pure_funcs: [ "Math.floor" ],
+        side_effects: true,
+    }
+    input: {
+        var a;
+        function f(b) {
+            Math.floor(a / b);
+            Math.floor(c / b);
+        }
+    }
+    expect: {
+        var a;
+        function f(b) {
+            c;
+        }
+    }
+}
+
+func: {
+    options = {
+        pure_funcs: function(node) {
+            return !~node.args[0].print_to_string().indexOf("a");
+        },
+        side_effects: true,
+    }
+    input: {
+        function f(a, b) {
+            Math.floor(a / b);
+            Math.floor(c / b);
+        }
+    }
+    expect: {
+        function f(a, b) {
+            Math.floor(c / b);
+        }
+    }
+}
+
+side_effects: {
+    options = {
+        pure_funcs: [ "console.log" ],
+        side_effects: true,
+    }
+    input: {
+        function f(a, b) {
+            console.log(a());
+            console.log(b);
+        }
+    }
+    expect: {
+        function f(a, b) {
+            a();
+        }
+    }
+}
+
+unused: {
+    options = {
+        pure_funcs: [ "pure" ],
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function foo() {
+            var u = pure(1);
+            var x = pure(2);
+            var y = pure(x);
+            var z = pure(pure(side_effects()));
+            return pure(3);
+        }
+    }
+    expect: {
+        function foo() {
+            side_effects();
+            return pure(3);
+        }
+    }
+}
+
+babel: {
+    options = {
+        pure_funcs: [ "_classCallCheck" ],
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function _classCallCheck(instance, Constructor) {
+            if (!(instance instanceof Constructor))
+                throw new TypeError("Cannot call a class as a function");
+        }
+        var Foo = function Foo() {
+            _classCallCheck(this, Foo);
+        };
+    }
+    expect: {
+        function _classCallCheck(instance, Constructor) {
+            if (!(instance instanceof Constructor))
+                throw new TypeError("Cannot call a class as a function");
+        }
+        var Foo = function() {
+        };
+    }
+}
+
+conditional: {
+    options = {
+        pure_funcs: [ "pure" ],
+        side_effects: true,
+    }
+    input: {
+        pure(1 | a() ? 2 & b() : 7 ^ c());
+        pure(1 | a() ? 2 & b() : 5);
+        pure(1 | a() ? 4 : 7 ^ c());
+        pure(1 | a() ? 4 : 5);
+        pure(3 ? 2 & b() : 7 ^ c());
+        pure(3 ? 2 & b() : 5);
+        pure(3 ? 4 : 7 ^ c());
+        pure(3 ? 4 : 5);
+    }
+    expect: {
+        1 | a() ? b() : c();
+        1 | a() && b();
+        1 | a() || c();
+        a();
+        3 ? b() : c();
+        3 && b();
+        3 || c();
+    }
+}
+
+relational: {
+    options = {
+        pure_funcs: [ "foo" ],
+        side_effects :true,
+    }
+    input: {
+        foo() in foo();
+        foo() instanceof bar();
+        foo() < "bar";
+        bar() > foo();
+        bar() != bar();
+        bar() !== "bar";
+        "bar" == foo();
+        "bar" === bar();
+        "bar" >= "bar";
+    }
+    expect: {
+        bar();
+        bar();
+        bar(), bar();
+        bar();
+        bar();
+    }
+}
+
+arithmetic: {
+    options = {
+        pure_funcs: [ "foo" ],
+        side_effects :true,
+    }
+    input: {
+        foo() + foo();
+        foo() - bar();
+        foo() * "bar";
+        bar() / foo();
+        bar() & bar();
+        bar() | "bar";
+        "bar" >> foo();
+        "bar" << bar();
+        "bar" >>> "bar";
+    }
+    expect: {
+        bar();
+        bar();
+        bar(), bar();
+        bar();
+        bar();
+    }
+}
+
+boolean_and: {
+    options = {
+        pure_funcs: [ "foo" ],
+        side_effects :true,
+    }
+    input: {
+        foo() && foo();
+        foo() && bar();
+        foo() && "bar";
+        bar() && foo();
+        bar() && bar();
+        bar() && "bar";
+        "bar" && foo();
+        "bar" && bar();
+        "bar" && "bar";
+    }
+    expect: {
+        foo() && bar();
+        bar();
+        bar() && bar();
+        bar();
+        "bar" && bar();
+    }
+}
+
+boolean_or: {
+    options = {
+        pure_funcs: [ "foo" ],
+        side_effects :true,
+    }
+    input: {
+        foo() || foo();
+        foo() || bar();
+        foo() || "bar";
+        bar() || foo();
+        bar() || bar();
+        bar() || "bar";
+        "bar" || foo();
+        "bar" || bar();
+        "bar" || "bar";
+    }
+    expect: {
+        foo() || bar();
+        bar();
+        bar() || bar();
+        bar();
+        "bar" || bar();
+    }
+}
+
+assign: {
+    options = {
+        pure_funcs: [ "foo" ],
+        side_effects :true,
+    }
+    input: {
+        var a;
+        function f(b) {
+            a = foo();
+            b *= 4 + foo();
+            c >>= 0 | foo();
+        }
+    }
+    expect: {
+        var a;
+        function f(b) {
+            a = foo();
+            b *= 4 + foo();
+            c >>= 0 | foo();
+        }
+    }
+}
+
+unary: {
+    options = {
+        pure_funcs: [ "foo" ],
+        side_effects :true,
+    }
+    input: {
+        typeof foo();
+        typeof bar();
+        typeof "bar";
+        void foo();
+        void bar();
+        void "bar";
+        delete a[foo()];
+        delete a[bar()];
+        delete a["bar"];
+        a[foo()]++;
+        a[bar()]++;
+        a["bar"]++;
+        --a[foo()];
+        --a[bar()];
+        --a["bar"];
+        ~foo();
+        ~bar();
+        ~"bar";
+    }
+    expect: {
+        bar();
+        bar();
+        delete a[foo()];
+        delete a[bar()];
+        delete a["bar"];
+        a[foo()]++;
+        a[bar()]++;
+        a["bar"]++;
+        --a[foo()];
+        --a[bar()];
+        --a["bar"];
+        bar();
+    }
+}