v2.8.23

- deep cloning of `AST_LabeledStatement`
- `L:do{...}while(false)`
- empty statement with label within block

extend `test/ufuzz.js`
- generate labels for blocks & loops
- generate for-in statements
- skip suspicious option search if `minify()` errs

fixes #1833

.gitattributes

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

.github/ISSUE_TEMPLATE.md

@@ -0,0 +1,9 @@
+- Bug report or feature request? <!-- Note: sub-optimal but correct code is not a bug -->
+- `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 branch.
+-->

.travis.yml

@@ -1,10 +1,12 @@
 language: node_js
 before_install: "npm install -g npm"
 node_js:
-    - "0.12"
     - "0.10"
+    - "0.12"
     - "4"
     - "6"
+env:
+    - UGLIFYJS_TEST_ALL=1
 matrix:
   fast_finish: true
 sudo: false

README.md

@@ -10,6 +10,11 @@ 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.
+- Node 7 has a known performance regression and runs `uglify-js` twice as slow.
+
 Install
 -------
 
@@ -62,14 +67,17 @@ The available options are:
   --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.
+                                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 6-8 quirks.
+                                Internet Explorer 6/7/8.
                                 By default UglifyJS will not try to be IE-proof.
-  --support-ie8                 Use this flag to support Internet Explorer 6-8 quirks.
-                                Note: may break standards compliant `catch` identifiers.
+  --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
@@ -83,10 +91,9 @@ The available options are:
   -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. Pass
-                                options like -c
-                                hoist_vars=false,if_return=false. Use -c with
-                                no argument to use the default compression
+  -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
@@ -97,8 +104,8 @@ The available options are:
                                 "@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.
+                                - 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
@@ -147,8 +154,10 @@ The available options are:
                                 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                  List of functions that can be safely removed if
-                                their return value is not used           [array]
+  --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
@@ -194,9 +203,10 @@ 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
 
@@ -284,6 +294,32 @@ 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
@@ -316,6 +352,12 @@ to set `true`; it's effectively a shortcut for `foo=true`).
   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
 
@@ -331,7 +373,15 @@ to set `true`; it's effectively a shortcut for `foo=true`).
 - `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
 
@@ -345,8 +395,11 @@ to set `true`; it's effectively a shortcut for `foo=true`).
 - `cascade` -- small optimization for sequences, transform `x, x` into `x`
   and `x = something(), x` into `x = something()`
 
-- `collapse_vars` -- default `false`. Collapse single-use `var` and `const`
-  definitions when possible.
+- `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.
@@ -358,6 +411,8 @@ to set `true`; it's effectively a shortcut for `foo=true`).
 - `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.
+  Specify `"strict"` to treat `foo.bar` as side-effect-free only when
+  `foo` is certain to not throw, i.e. not `null` or `undefined`.
 
 - `pure_funcs` -- default `null`.  You can pass an array of names and
   UglifyJS will assume that those functions do not produce side
@@ -371,20 +426,28 @@ to set `true`; it's effectively a shortcut for `foo=true`).
   overhead (compression will be slower).
 
 - `drop_console` -- default `false`.  Pass `true` to discard calls to
-  `console.*` functions.
+  `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 mangling/discarding function names.  Useful for code relying on
-  `Function.prototype.name`.
+  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.
 
+- `keep_infinity` -- default `false`. Pass `true` to prevent `Infinity` from
+  being compressed into `1/0`, which may cause performance issues on Chrome.
+
 ### The `unsafe` option
 
 It enables some transformations that *might* break code logic in certain
@@ -413,6 +476,8 @@ 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.
@@ -423,8 +488,6 @@ separate file and include it into the build.  For example you can have a
 ```javascript
 const DEBUG = false;
 const PRODUCTION = true;
-// Alternative for environments that don't support `const`
-/** @const */ var STAGING = false;
 // etc.
 ```
 
@@ -435,7 +498,8 @@ 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 build will contain the `const` declarations if you use
-them. If you are targeting < ES6 environments, use `/** @const */ var`.
+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>
 
@@ -570,7 +634,7 @@ function uglify(ast, options, mangle) {
 
   // Compression
   uAST.figure_out_scope();
-  uAST = uAST.transform(UglifyJS.Compressor(options));
+  uAST = UglifyJS.Compressor(options).compress(uAST);
 
   // Mangling (optional)
   if (mangle) {
@@ -628,9 +692,26 @@ 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
@@ -663,6 +744,17 @@ var result = UglifyJS.minify("compiled.js", {
 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.
@@ -693,9 +785,13 @@ Other options:
  - `toplevel` — mangle names declared in the toplevel scope (disabled by
   default).
 
-  - `eval` — mangle names visible in scopes where eval or with are used
+ - `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
@@ -709,10 +805,10 @@ Other options:
   UglifyJS.minify("tst.js").code;
   // 'function funcName(a,n){}var globalVar;'
 
-  UglifyJS.minify("tst.js", { mangle: { except: ['firstLongName'] }}).code;
+  UglifyJS.minify("tst.js", { mangle: { except: ['firstLongName'] } }).code;
   // 'function funcName(firstLongName,a){}var globalVar;'
 
-  UglifyJS.minify("tst.js", { mangle: toplevel: true }}).code;
+  UglifyJS.minify("tst.js", { mangle: { toplevel: true } }).code;
   // 'function n(n,a){}var a;'
   ```
 
@@ -720,6 +816,7 @@ Other 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!
@@ -781,7 +878,7 @@ 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
@@ -826,8 +923,11 @@ 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.
@@ -882,3 +982,20 @@ The `source_map_options` (optional) can contain the following properties:
   [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/uglifyjs

@@ -8,7 +8,6 @@ var sys = require("util");
 var yargs = require("yargs");
 var fs = require("fs");
 var path = require("path");
-var async = require("async");
 var acorn;
 var screw_ie8 = true;
 var ARGS = yargs
@@ -23,10 +22,11 @@ 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-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", "Do not support Internet Explorer 6-8 quirks. This flag is enabled by default.")
-    .describe("support-ie8", "Support non-standard Internet Explorer 6-8 javascript. Note: may break standards compliant `catch` identifiers.")
+    .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. \
@@ -46,7 +46,7 @@ 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.")
@@ -76,6 +76,7 @@ You need to pass an argument to this option to specify the name that your module
     .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")
@@ -96,6 +97,7 @@ You need to pass an argument to this option to specify the name that your module
     .string("beautify")
     .string("m")
     .string("mangle")
+    .string("mangle-props-debug")
     .string("c")
     .string("compress")
     .string("d")
@@ -112,6 +114,7 @@ You need to pass an argument to this option to specify the name that your module
     .array("pure-funcs")
 
     .boolean("expr")
+    .boolean("source-map-inline")
     .boolean("source-map-include-sources")
     .boolean("screw-ie8")
     .boolean("support-ie8")
@@ -130,6 +133,7 @@ You need to pass an argument to this option to specify the name that your module
     .boolean("bare-returns")
     .boolean("keep-fnames")
     .boolean("reserve-domprops")
+    .boolean("wrap-iife")
 
     .wrap(80)
 
@@ -223,9 +227,10 @@ if (ARGS.mangle_props === true) {
 }
 
 var OUTPUT_OPTIONS = {
-    beautify    : BEAUTIFY ? true : false,
-    preamble    : ARGS.preamble || null,
-    quote_style : ARGS.quotes != null ? ARGS.quotes : 0
+    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) {
@@ -247,32 +252,25 @@ if (ARGS.keep_fnames) {
     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 != null) {
-    if (/^\/.*\/[a-zA-Z]*$/.test(ARGS.comments)) {
-        try {
-            OUTPUT_OPTIONS.comments = extractRegex(ARGS.comments);
-        } catch (e) {
-            print_error("ERROR: Invalid --comments: " + e.message);
-        }
-    } 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) {
         print_error("WARN: Ignoring input files since --self was passed");
@@ -283,21 +281,29 @@ if (ARGS.self) {
 
 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) {
         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 (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);
+    }
+}
+
 if (files.indexOf("-") >= 0 && ARGS.source_map) {
     print_error("ERROR: Source map doesn't work with input from STDIN");
     process.exit(1);
@@ -309,37 +315,22 @@ if (files.filter(function(el){ return el == "-" }).length > 1) {
 }
 
 var STATS = {};
-var OUTPUT_FILE = ARGS.o;
 var TOPLEVEL = null;
 var P_RELATIVE = ARGS.p && ARGS.p == "relative";
 var SOURCES_CONTENT = {};
+var index = 0;
 
-var SOURCE_MAP = ARGS.source_map ? UglifyJS.SourceMap({
-    file: P_RELATIVE ? path.relative(path.dirname(ARGS.source_map), OUTPUT_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) {
-        print_error(ex.msg);
-        print_error("Supported options:");
-        print_error(sys.inspect(ex.defs));
-        process.exit(1);
-    }
-}
-
-async.eachLimit(files, 1, function (file, cb) {
+!function cb() {
+    if (index == files.length) return done();
+    var file = files[index++];
     read_whole_file(file, function (err, code) {
         if (err) {
             print_error("ERROR: can't read file: " + file);
             process.exit(1);
         }
+        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, '/');
@@ -375,7 +366,21 @@ async.eachLimit(files, 1, function (file, cb) {
                 } catch(ex) {
                     if (ex instanceof UglifyJS.JS_Parse_Error) {
                         print_error("Parse error at " + file + ":" + ex.line + "," + ex.col);
-                        print_error(ex.message);
+                        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);
                     }
@@ -385,7 +390,31 @@ async.eachLimit(files, 1, function (file, cb) {
         });
         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);
     });
@@ -422,17 +451,19 @@ async.eachLimit(files, 1, function (file, cb) {
             cache         : cache,
             only_cache    : !ARGS.mangle_props,
             regex         : regex,
-            ignore_quoted : ARGS.mangle_props == 2
+            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: screw_ie8, cache: TL_CACHE });
+            TOPLEVEL.figure_out_scope(MANGLE || { screw_ie8: screw_ie8, cache: TL_CACHE });
             if (ARGS.lint) {
                 TOPLEVEL.scope_warnings();
             }
@@ -447,7 +478,7 @@ async.eachLimit(files, 1, function (file, cb) {
 
     if (SCOPE_IS_NEEDED) {
         time_it("scope", function(){
-            TOPLEVEL.figure_out_scope({ screw_ie8: screw_ie8, cache: TL_CACHE });
+            TOPLEVEL.figure_out_scope(MANGLE || { screw_ie8: screw_ie8, cache: TL_CACHE });
             if (MANGLE && !TL_CACHE) {
                 TOPLEVEL.compute_char_frequency(MANGLE);
             }
@@ -455,7 +486,6 @@ async.eachLimit(files, 1, function (file, cb) {
     }
 
     if (MANGLE) time_it("mangle", function(){
-        MANGLE.cache = TL_CACHE;
         TOPLEVEL.mangle_names(MANGLE);
     });
 
@@ -479,13 +509,18 @@ async.eachLimit(files, 1, function (file, cb) {
         output = output.get();
 
         if (SOURCE_MAP) {
-            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 (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) {
@@ -506,7 +541,7 @@ async.eachLimit(files, 1, function (file, cb) {
             }));
         }
     }
-});
+}
 
 /* -----[ functions ]----- */
 
@@ -526,7 +561,7 @@ function getOptions(flag, constants) {
 
         var ast;
         try {
-            ast = UglifyJS.parse(x, { expression: true });
+            ast = UglifyJS.parse(x, { cli: true, expression: true });
         } catch(ex) {
             if (ex instanceof UglifyJS.JS_Parse_Error) {
                 print_error("Error parsing arguments for flag `" + flag + "': " + x);
@@ -536,7 +571,7 @@ function getOptions(flag, constants) {
         ast.walk(new UglifyJS.TreeWalker(function(node){
             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() + ")")();
@@ -544,7 +579,7 @@ function getOptions(flag, constants) {
                 return true;    // no descend
             }
             if (node instanceof UglifyJS.AST_Symbol || node instanceof UglifyJS.AST_Binary) {
-                var name = node.print_to_string({ beautify: false }).replace(/-/g, "_");
+                var name = node.print_to_string().replace(/-/g, "_");
                 ret[name] = true;
                 return true;    // no descend
             }
@@ -571,6 +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();

lib/ast.js

@@ -81,7 +81,9 @@ function DEFNODE(type, props, methods, base) {
     ctor.DEFMETHOD = function(name, method) {
         this.prototype[name] = method;
     };
-    exports["AST_" + type] = ctor;
+    if (typeof exports !== "undefined") {
+        exports["AST_" + type] = ctor;
+    }
     return ctor;
 };
 
@@ -89,9 +91,20 @@ var AST_Token = DEFNODE("Token", "type value line col pos endline endcol endpos
 }, 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",
@@ -143,12 +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_Statement) {
+        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", {
@@ -196,6 +210,21 @@ 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 label = node.label;
+            var def = this.label;
+            node.walk(new TreeWalker(function(node) {
+                if (node instanceof AST_LoopControl
+                    && node.label && node.label.thedef === def) {
+                    node.label.thedef = label;
+                    label.references.push(node);
+                }
+            }));
+        }
+        return node;
     }
 }, AST_StatementWithBody);
 
@@ -369,9 +398,10 @@ var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments", {
     _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);
         });
     }
@@ -531,9 +561,10 @@ 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);
@@ -571,9 +602,10 @@ 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);
+            }
         });
     }
 });
@@ -740,9 +772,10 @@ 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);
+            }
         });
     }
 });
@@ -754,9 +787,10 @@ 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);
+            }
         });
     }
 });
@@ -804,9 +838,6 @@ 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, {
@@ -954,8 +985,8 @@ TreeWalker.prototype = {
     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] ? "up" : true;
+        } else if (node instanceof AST_Directive && !this.directives[node.value]) {
+            this.directives[node.value] = node;
         }
         this.stack.push(node);
     },
@@ -983,7 +1014,7 @@ TreeWalker.prototype = {
             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 true;
+                if (st.value == type) return st;
             }
         }
     },
@@ -1005,16 +1036,16 @@ TreeWalker.prototype = {
             self = p;
         }
     },
-    loopcontrol_target: function(label) {
+    loopcontrol_target: function(node) {
         var stack = this.stack;
-        if (label) for (var i = stack.length; --i >= 0;) {
+        if (node.label) for (var i = stack.length; --i >= 0;) {
             var x = stack[i];
-            if (x instanceof AST_LabeledStatement && x.label.name == label.name) {
+            if (x instanceof AST_LabeledStatement && x.label.name == node.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)
+            if (x instanceof AST_IterationStatement
+                || node instanceof AST_Break && x instanceof AST_Switch)
                 return x;
         }
     }

lib/output.js

@@ -45,31 +45,65 @@
 
 var EXPECT_DIRECTIVE = /^$|[;{][\s\n]*$/;
 
+function is_some_comments(comment) {
+    // multiline comment
+    return comment.type == "comment2" && /@preserve|@license|@cc_on/i.test(comment.value);
+}
+
 function OutputStream(options) {
 
     options = defaults(options, {
-        indent_start     : 0,
-        indent_level     : 4,
-        quote_keys       : false,
-        space_colon      : true,
         ascii_only       : false,
-        unescape_regexps : false,
-        inline_script    : false,
-        width            : 80,
-        max_line_len     : 32000,
         beautify         : false,
-        source_map       : null,
         bracketize       : false,
-        semicolons       : true,
         comments         : false,
-        shebang          : true,
-        preserve_line    : false,
-        screw_ie8        : true,
+        indent_level     : 4,
+        indent_start     : 0,
+        inline_script    : true,
+        keep_quoted_props: false,
+        max_line_len     : false,
         preamble         : null,
+        preserve_line    : false,
+        quote_keys       : false,
         quote_style      : 0,
-        keep_quoted_props: false
+        screw_ie8        : true,
+        semicolons       : true,
+        shebang          : true,
+        source_map       : null,
+        space_colon      : true,
+        unescape_regexps : false,
+        width            : 80,
+        wrap_iife        : false,
     }, true);
 
+    // Convert comment option to RegExp if neccessary and set up comments filter
+    var comment_filter = return_false; // Default case, throw all comments away
+    if (options.comments) {
+        var comments = options.comments;
+        if (typeof options.comments === "string" && /^\/.*\/[a-zA-Z]*$/.test(options.comments)) {
+            var regex_pos = options.comments.lastIndexOf("/");
+            comments = new RegExp(
+                options.comments.substr(1, regex_pos - 1),
+                options.comments.substr(regex_pos + 1)
+            );
+        }
+        if (comments instanceof RegExp) {
+            comment_filter = function(comment) {
+                return comment.type != "comment5" && comments.test(comment.value);
+            };
+        }
+        else if (typeof comments === "function") {
+            comment_filter = function(comment) {
+                return comment.type != "comment5" && comments(this, comment);
+            };
+        }
+        else if (comments === "some") {
+            comment_filter = is_some_comments;
+        } else { // NOTE includes "all" option
+            comment_filter = return_true;
+        }
+    }
+
     var indentation = 0;
     var current_col = 0;
     var current_line = 1;
@@ -155,31 +189,42 @@ function OutputStream(options) {
 
     var might_need_space = false;
     var might_need_semicolon = false;
-    var last = null;
+    var might_add_newline = 0;
+    var last = "";
 
-    function last_char() {
-        return last.charAt(last.length - 1);
-    };
-
-    function maybe_newline() {
-        if (options.max_line_len && current_col > options.max_line_len)
-            print("\n");
-    };
+    var ensure_line_len = options.max_line_len ? function() {
+        if (current_col > options.max_line_len) {
+            if (might_add_newline) {
+                var left = OUTPUT.slice(0, might_add_newline);
+                var right = OUTPUT.slice(might_add_newline);
+                OUTPUT = left + "\n" + right;
+                current_line++;
+                current_pos++;
+                current_col = right.length;
+            }
+            if (current_col > options.max_line_len) {
+                AST_Node.warn("Output exceeds {max_line_len} characters", options);
+            }
+        }
+        might_add_newline = 0;
+    } : noop;
 
     var requireSemicolonChars = makePredicate("( [ + * / - , .");
 
     function print(str) {
         str = String(str);
         var ch = str.charAt(0);
+        var prev = last.charAt(last.length - 1);
         if (might_need_semicolon) {
             might_need_semicolon = false;
 
-            if ((!ch || ";}".indexOf(ch) < 0) && !/[;]$/.test(last)) {
+            if (prev == ":" && ch == "}" || (!ch || ";}".indexOf(ch) < 0) && prev != ";") {
                 if (options.semicolons || requireSemicolonChars(ch)) {
                     OUTPUT += ";";
                     current_col++;
                     current_pos++;
                 } else {
+                    ensure_line_len();
                     OUTPUT += "\n";
                     current_pos++;
                     current_line++;
@@ -200,6 +245,7 @@ function OutputStream(options) {
         if (!options.beautify && options.preserve_line && stack[stack.length - 1]) {
             var target_line = stack[stack.length - 1].start.line;
             while (current_line < target_line) {
+                ensure_line_len();
                 OUTPUT += "\n";
                 current_pos++;
                 current_line++;
@@ -209,10 +255,10 @@ function OutputStream(options) {
         }
 
         if (might_need_space) {
-            var prev = last_char();
             if ((is_identifier_char(prev)
-                 && (is_identifier_char(ch) || ch == "\\"))
-                || (/^[\+\-\/]$/.test(ch) && ch == prev))
+                    && (is_identifier_char(ch) || ch == "\\"))
+                || (ch == "/" && ch == prev)
+                || ((ch == "+" || ch == "-") && ch == last))
             {
                 OUTPUT += " ";
                 current_col++;
@@ -220,16 +266,16 @@ function OutputStream(options) {
             }
             might_need_space = false;
         }
+        OUTPUT += str;
+        current_pos += str.length;
         var a = str.split(/\r?\n/), n = a.length - 1;
         current_line += n;
-        if (n == 0) {
-            current_col += a[n].length;
-        } else {
+        current_col += a[0].length;
+        if (n > 0) {
+            ensure_line_len();
             current_col = a[n].length;
         }
-        current_pos += str.length;
         last = str;
-        OUTPUT += str;
     };
 
     var space = options.beautify ? function() {
@@ -255,7 +301,10 @@ function OutputStream(options) {
 
     var newline = options.beautify ? function() {
         print("\n");
-    } : maybe_newline;
+    } : options.max_line_len ? function() {
+        ensure_line_len();
+        might_add_newline = OUTPUT.length;
+    } : noop;
 
     var semicolon = options.beautify ? function() {
         print(";");
@@ -332,13 +381,12 @@ function OutputStream(options) {
     } : noop;
 
     function get() {
+        if (might_add_newline) {
+            ensure_line_len();
+        }
         return OUTPUT;
     };
 
-    if (options.preamble) {
-        print(options.preamble.replace(/\r\n?|[\n\u2028\u2029]|\s*$/g, "\n"));
-    }
-
     var stack = [];
     return {
         get             : get,
@@ -376,12 +424,12 @@ function OutputStream(options) {
         with_square     : with_square,
         add_mapping     : add_mapping,
         option          : function(opt) { return options[opt] },
+        comment_filter  : comment_filter,
         line            : function() { return current_line },
         col             : function() { return current_col },
         pos             : function() { return current_pos },
         push_node       : function(node) { stack.push(node) },
         pop_node        : function() { return stack.pop() },
-        stack           : function() { return stack },
         parent          : function(n) {
             return stack[stack.length - 2 - (n || 0)];
         }
@@ -435,7 +483,7 @@ function OutputStream(options) {
 
     AST_Node.DEFMETHOD("add_comments", function(output){
         if (output._readonly) return;
-        var c = output.option("comments"), self = this;
+        var self = this;
         var start = self.start;
         if (start && !start._comments_dumped) {
             start._comments_dumped = true;
@@ -458,20 +506,19 @@ function OutputStream(options) {
                 }));
             }
 
-            if (!c) {
-                comments = comments.filter(function(comment) {
-                    return comment.type == "comment5";
-                });
-            } else if (c.test) {
-                comments = comments.filter(function(comment){
-                    return comment.type == "comment5" || c.test(comment.value);
-                });
-            } else if (typeof c == "function") {
-                comments = comments.filter(function(comment){
-                    return comment.type == "comment5" || c(self, comment);
-                });
+            if (output.pos() == 0) {
+                if (comments.length > 0 && output.option("shebang") && comments[0].type == "comment5") {
+                    output.print("#!" + comments.shift().value + "\n");
+                    output.indent();
+                }
+                var preamble = output.option("preamble");
+                if (preamble) {
+                    output.print(preamble.replace(/\r\n?|[\n\u2028\u2029]|\s*$/g, "\n"));
+                }
             }
 
+            comments = comments.filter(output.comment_filter, self);
+
             // Keep single line comments after nlb, after nlb
             if (!output.option("beautify") && comments.length > 0 &&
                 /comment[134]/.test(comments[0].type) &&
@@ -494,10 +541,6 @@ function OutputStream(options) {
                         output.space();
                     }
                 }
-                else if (output.pos() === 0 && c.type == "comment5" && output.option("shebang")) {
-                    output.print("#!" + c.value + "\n");
-                    output.indent();
-                }
             });
         }
     });
@@ -521,7 +564,16 @@ function OutputStream(options) {
     // a function expression needs parens around it when it's provably
     // the first token to appear in a statement.
     PARENS(AST_Function, function(output){
-        return first_in_statement(output);
+        if (first_in_statement(output)) {
+            return true;
+        }
+
+        if (output.option('wrap_iife')) {
+            var p = output.parent();
+            return p instanceof AST_Call && p.expression === this;
+        }
+
+        return false;
     });
 
     // same goes for an object literal, because otherwise it would be
@@ -530,10 +582,10 @@ function OutputStream(options) {
         return first_in_statement(output);
     });
 
-    PARENS([ AST_Unary, AST_Undefined ], function(output){
+    PARENS(AST_Unary, function(output){
         var p = output.parent();
         return p instanceof AST_PropAccess && p.expression === this
-            || p instanceof AST_New;
+            || p instanceof AST_Call && p.expression === this;
     });
 
     PARENS(AST_Seq, function(output){
@@ -721,7 +773,7 @@ function OutputStream(options) {
     DEFPRINT(AST_Do, function(self, output){
         output.print("do");
         output.space();
-        self._do_print_body(output);
+        make_block(self.body, output);
         output.space();
         output.print("while");
         output.space();
@@ -743,7 +795,7 @@ function OutputStream(options) {
         output.print("for");
         output.space();
         output.with_parens(function(){
-            if (self.init && !(self.init instanceof AST_EmptyStatement)) {
+            if (self.init) {
                 if (self.init instanceof AST_Definitions) {
                     self.init.print(output);
                 } else {
@@ -848,10 +900,10 @@ function OutputStream(options) {
 
     /* -----[ if ]----- */
     function make_then(self, output) {
-        if (output.option("bracketize")) {
-            make_block(self.body, output);
-            return;
-        }
+        var b = self.body;
+        if (output.option("bracketize")
+            || !output.option("screw_ie8") && b instanceof AST_Do)
+            return make_block(b, output);
         // The squeezer replaces "block"-s that contain only a single
         // statement with the statement itself; technically, the AST
         // is correct, but this can create problems when we output an
@@ -859,18 +911,7 @@ function OutputStream(options) {
         // IF *without* an ELSE block (then the outer ELSE would refer
         // to the inner IF).  This function checks for this case and
         // adds the block brackets if needed.
-        if (!self.body)
-            return output.force_semicolon();
-        if (self.body instanceof AST_Do) {
-            // Unconditionally use the if/do-while workaround for all browsers.
-            // https://github.com/mishoo/UglifyJS/issues/#issue/57 IE
-            // croaks with "syntax error" on code like this: if (foo)
-            // do ... while(cond); else ...  we need block brackets
-            // around do/while
-            make_block(self.body, output);
-            return;
-        }
-        var b = self.body;
+        if (!b) return output.force_semicolon();
         while (true) {
             if (b instanceof AST_If) {
                 if (!b.alternative) {
@@ -898,7 +939,10 @@ function OutputStream(options) {
             output.space();
             output.print("else");
             output.space();
-            force_statement(self.alternative, output);
+            if (self.alternative instanceof AST_If)
+                self.alternative.print(output);
+            else
+                force_statement(self.alternative, output);
         } else {
             self._do_print_body(output);
         }
@@ -912,24 +956,24 @@ function OutputStream(options) {
             self.expression.print(output);
         });
         output.space();
-        if (self.body.length > 0) output.with_block(function(){
-            self.body.forEach(function(stmt, i){
-                if (i) output.newline();
+        var last = self.body.length - 1;
+        if (last < 0) output.print("{}");
+        else output.with_block(function(){
+            self.body.forEach(function(branch, i){
                 output.indent(true);
-                stmt.print(output);
+                branch.print(output);
+                if (i < last && branch.body.length > 0)
+                    output.newline();
             });
         });
-        else output.print("{}");
     });
     AST_SwitchBranch.DEFMETHOD("_do_print_body", function(output){
-        if (this.body.length > 0) {
+        output.newline();
+        this.body.forEach(function(stmt){
+            output.indent();
+            stmt.print(output);
             output.newline();
-            this.body.forEach(function(stmt){
-                output.indent();
-                stmt.print(output);
-                output.newline();
-            });
-        }
+        });
     });
     DEFPRINT(AST_Default, function(self, output){
         output.print("default:");
@@ -1201,16 +1245,7 @@ function OutputStream(options) {
         var def = self.definition();
         output.print_name(def ? def.mangled_name || def.name : self.name);
     });
-    DEFPRINT(AST_Undefined, function(self, output){
-        output.print("void 0");
-    });
     DEFPRINT(AST_Hole, noop);
-    DEFPRINT(AST_Infinity, function(self, output){
-        output.print("Infinity");
-    });
-    DEFPRINT(AST_NaN, function(self, output){
-        output.print("NaN");
-    });
     DEFPRINT(AST_This, function(self, output){
         output.print("this");
     });
@@ -1276,15 +1311,7 @@ function OutputStream(options) {
 
     function force_statement(stat, output) {
         if (output.option("bracketize")) {
-            if (!stat || stat instanceof AST_EmptyStatement)
-                output.print("{}");
-            else if (stat instanceof AST_BlockStatement)
-                stat.print(output);
-            else output.with_block(function(){
-                output.indent();
-                stat.print(output);
-                output.newline();
-            });
+            make_block(stat, output);
         } else {
             if (!stat || stat instanceof AST_EmptyStatement)
                 output.force_semicolon();
@@ -1293,30 +1320,6 @@ function OutputStream(options) {
         }
     };
 
-    // 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(output) {
-        var a = output.stack(), i = a.length, node = a[--i], p = a[--i];
-        while (i > 0) {
-            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;
-                p = a[--i];
-            } else {
-                return false;
-            }
-        }
-    };
-
     // self should be AST_New.  decide if we want to show parens or not.
     function need_constructor_parens(self, output) {
         // Always print parentheses with arguments
@@ -1357,11 +1360,11 @@ function OutputStream(options) {
     };
 
     function make_block(stmt, output) {
-        if (stmt instanceof AST_BlockStatement) {
+        if (!stmt || stmt instanceof AST_EmptyStatement)
+            output.print("{}");
+        else if (stmt instanceof AST_BlockStatement)
             stmt.print(output);
-            return;
-        }
-        output.with_block(function(){
+        else output.with_block(function(){
             output.indent();
             stmt.print(output);
             output.newline();

lib/parse.js

@@ -195,12 +195,11 @@ function JS_Parse_Error(message, filename, line, col, pos) {
     this.line = line;
     this.col = col;
     this.pos = pos;
-    this.stack = new Error().stack;
-};
-
-JS_Parse_Error.prototype.toString = function() {
-    return this.message + " (line: " + this.line + ", col: " + this.col + ", pos: " + this.pos + ")" + "\n\n" + this.stack;
 };
+JS_Parse_Error.prototype = Object.create(Error.prototype);
+JS_Parse_Error.prototype.constructor = JS_Parse_Error;
+JS_Parse_Error.prototype.name = "SyntaxError";
+configure_error_stack(JS_Parse_Error);
 
 function js_error(message, filename, line, col, pos) {
     throw new JS_Parse_Error(message, filename, line, col, pos);
@@ -349,11 +348,14 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
             return is_alphanumeric_char(code);
         });
         if (prefix) num = prefix + num;
+        if (RE_OCT_NUMBER.test(num) && next_token.has_directive("use strict")) {
+            parse_error("Legacy octal literals are not allowed in strict mode");
+        }
         var valid = parse_js_number(num);
         if (!isNaN(valid)) {
             return token("num", valid);
         } else {
-            parse_error("SyntaxError: Invalid syntax: " + num);
+            parse_error("Invalid syntax: " + num);
         }
     };
 
@@ -392,7 +394,7 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
         // Parse
         if (ch === "0") return "\0";
         if (ch.length > 0 && next_token.has_directive("use strict"))
-            parse_error("SyntaxError: Octal literals are not allowed in strict mode");
+            parse_error("Legacy octal escape sequences are not allowed in strict mode");
         return String.fromCharCode(parseInt(ch, 8));
     }
 
@@ -401,18 +403,18 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
         for (; n > 0; --n) {
             var digit = parseInt(next(true), 16);
             if (isNaN(digit))
-                parse_error("SyntaxError: Invalid hex-character pattern in string");
+                parse_error("Invalid hex-character pattern in string");
             num = (num << 4) | digit;
         }
         return num;
     };
 
-    var read_string = with_eof_error("SyntaxError: Unterminated string constant", function(quote_char){
+    var read_string = with_eof_error("Unterminated string constant", function(quote_char){
         var quote = next(), ret = "";
         for (;;) {
             var ch = next(true, true);
             if (ch == "\\") ch = read_escaped_char(true);
-            else if (NEWLINE_CHARS(ch)) parse_error("SyntaxError: Unterminated string constant");
+            else if (NEWLINE_CHARS(ch)) parse_error("Unterminated string constant");
             else if (ch == quote) break;
             ret += ch;
         }
@@ -437,7 +439,7 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
         return next_token;
     };
 
-    var skip_multiline_comment = with_eof_error("SyntaxError: Unterminated multiline comment", function(){
+    var skip_multiline_comment = with_eof_error("Unterminated multiline comment", function(){
         var regex_allowed = S.regex_allowed;
         var i = find("*/", true);
         var text = S.text.substring(S.pos, i).replace(/\r\n|\r|\u2028|\u2029/g, '\n');
@@ -457,9 +459,9 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
                 else break;
             }
             else {
-                if (ch != "u") parse_error("SyntaxError: Expecting UnicodeEscapeSequence -- uXXXX");
+                if (ch != "u") parse_error("Expecting UnicodeEscapeSequence -- uXXXX");
                 ch = read_escaped_char();
-                if (!is_identifier_char(ch)) parse_error("SyntaxError: Unicode char: " + ch.charCodeAt(0) + " is not valid in identifier");
+                if (!is_identifier_char(ch)) parse_error("Unicode char: " + ch.charCodeAt(0) + " is not valid in identifier");
                 name += ch;
                 backslash = false;
             }
@@ -471,10 +473,10 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
         return name;
     };
 
-    var read_regexp = with_eof_error("SyntaxError: Unterminated regular expression", function(regexp){
+    var read_regexp = with_eof_error("Unterminated regular expression", function(regexp){
         var prev_backslash = false, ch, in_class = false;
         while ((ch = next(true))) if (NEWLINE_CHARS(ch)) {
-            parse_error("SyntaxError: Unexpected line terminator");
+            parse_error("Unexpected line terminator");
         } else if (prev_backslash) {
             regexp += "\\" + ch;
             prev_backslash = false;
@@ -556,6 +558,11 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
     function next_token(force_regexp) {
         if (force_regexp != null)
             return read_regexp(force_regexp);
+        if (shebang && S.pos == 0 && looking_at("#!")) {
+            start_token();
+            forward(2);
+            skip_line_comment("comment5");
+        }
         for (;;) {
             skip_whitespace();
             start_token();
@@ -587,16 +594,9 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
             if (PUNC_CHARS(ch)) return token("punc", next());
             if (OPERATOR_CHARS(ch)) return read_operator();
             if (code == 92 || is_identifier_start(code)) return read_word();
-            if (shebang) {
-                if (S.pos == 0 && looking_at("#!")) {
-                    forward(2);
-                    skip_line_comment("comment5");
-                    continue;
-                }
-            }
             break;
         }
-        parse_error("SyntaxError: Unexpected character '" + ch + "'");
+        parse_error("Unexpected character '" + ch + "'");
     };
 
     next_token.context = function(nc) {
@@ -688,13 +688,14 @@ var ATOMIC_START_TOKEN = array_to_hash([ "atom", "num", "string", "regexp", "nam
 function parse($TEXT, options) {
 
     options = defaults(options, {
-        strict         : false,
-        filename       : null,
-        toplevel       : null,
-        expression     : false,
-        html5_comments : true,
         bare_returns   : false,
+        cli            : false,
+        expression     : false,
+        filename       : null,
+        html5_comments : true,
         shebang        : true,
+        strict         : false,
+        toplevel       : null,
     });
 
     var S = {
@@ -753,14 +754,14 @@ function parse($TEXT, options) {
     function unexpected(token) {
         if (token == null)
             token = S.token;
-        token_error(token, "SyntaxError: Unexpected token: " + token.type + " (" + token.value + ")");
+        token_error(token, "Unexpected token: " + token.type + " (" + token.value + ")");
     };
 
     function expect_token(type, val) {
         if (is(type, val)) {
             return next();
         }
-        token_error(S.token, "SyntaxError: Unexpected token " + S.token.type + " «" + S.token.value + "»" + ", expected " + type + " «" + val + "»");
+        token_error(S.token, "Unexpected token " + S.token.type + " «" + S.token.value + "»" + ", expected " + type + " «" + val + "»");
     };
 
     function expect(punc) { return expect_token("punc", punc); };
@@ -889,7 +890,7 @@ function parse($TEXT, options) {
 
               case "return":
                 if (S.in_function == 0 && !options.bare_returns)
-                    croak("SyntaxError: 'return' outside of function");
+                    croak("'return' outside of function");
                 return new AST_Return({
                     value: ( is("punc", ";")
                              ? (next(), null)
@@ -906,7 +907,7 @@ function parse($TEXT, options) {
 
               case "throw":
                 if (S.token.nlb)
-                    croak("SyntaxError: Illegal newline after 'throw'");
+                    croak("Illegal newline after 'throw'");
                 return new AST_Throw({
                     value: (tmp = expression(true), semicolon(), tmp)
                 });
@@ -922,17 +923,15 @@ function parse($TEXT, options) {
 
               case "with":
                 if (S.input.has_directive("use strict")) {
-                    croak("SyntaxError: Strict mode may not include a with statement");
+                    croak("Strict mode may not include a with statement");
                 }
                 return new AST_With({
                     expression : parenthesised(),
                     body       : statement()
                 });
-
-              default:
-                unexpected();
             }
         }
+        unexpected();
     });
 
     function labeled_statement() {
@@ -942,7 +941,7 @@ function parse($TEXT, options) {
             // syntactically incorrect if it contains a
             // LabelledStatement that is enclosed by a
             // LabelledStatement with the same Identifier as label.
-            croak("SyntaxError: Label " + label.name + " defined twice");
+            croak("Label " + label.name + " defined twice");
         }
         expect(":");
         S.labels.push(label);
@@ -955,7 +954,7 @@ function parse($TEXT, options) {
             label.references.forEach(function(ref){
                 if (ref instanceof AST_Continue) {
                     ref = ref.label.start;
-                    croak("SyntaxError: Continue label `" + label.name + "` refers to non-IterationStatement.",
+                    croak("Continue label `" + label.name + "` refers to non-IterationStatement.",
                           ref.line, ref.col, ref.pos);
                 }
             });
@@ -975,11 +974,11 @@ function parse($TEXT, options) {
         if (label != null) {
             ldef = find_if(function(l){ return l.name == label.name }, S.labels);
             if (!ldef)
-                croak("SyntaxError: Undefined label " + label.name);
+                croak("Undefined label " + label.name);
             label.thedef = ldef;
         }
         else if (S.in_loop == 0)
-            croak("SyntaxError: " + type.TYPE + " not inside a loop or switch");
+            croak(type.TYPE + " not inside a loop or switch");
         semicolon();
         var stat = new type({ label: label });
         if (ldef) ldef.references.push(stat);
@@ -995,7 +994,7 @@ function parse($TEXT, options) {
                 : expression(true, true);
             if (is("operator", "in")) {
                 if (init instanceof AST_Var && init.definitions.length > 1)
-                    croak("SyntaxError: Only one variable declaration allowed in for..in loop");
+                    croak("Only one variable declaration allowed in for..in loop");
                 next();
                 return for_in(init);
             }
@@ -1145,7 +1144,7 @@ function parse($TEXT, options) {
             });
         }
         if (!bcatch && !bfinally)
-            croak("SyntaxError: Missing catch/finally blocks");
+            croak("Missing catch/finally blocks");
         return new AST_Try({
             body     : body,
             bcatch   : bcatch,
@@ -1239,7 +1238,7 @@ function parse($TEXT, options) {
             break;
           case "operator":
             if (!is_identifier_string(tok.value)) {
-                croak("SyntaxError: Invalid getter/setter name: " + tok.value,
+                croak("Invalid getter/setter name: " + tok.value,
                     tok.line, tok.col, tok.pos);
             }
             ret = _make_symbol(AST_SymbolRef);
@@ -1305,6 +1304,10 @@ function parse($TEXT, options) {
         });
     });
 
+    var create_accessor = embed_tokens(function() {
+        return function_(AST_Accessor);
+    });
+
     var object_ = embed_tokens(function() {
         expect("{");
         var first = true, a = [];
@@ -1321,7 +1324,7 @@ function parse($TEXT, options) {
                     a.push(new AST_ObjectGetter({
                         start : start,
                         key   : as_atom_node(),
-                        value : function_(AST_Accessor),
+                        value : create_accessor(),
                         end   : prev()
                     }));
                     continue;
@@ -1330,7 +1333,7 @@ function parse($TEXT, options) {
                     a.push(new AST_ObjectSetter({
                         start : start,
                         key   : as_atom_node(),
-                        value : function_(AST_Accessor),
+                        value : create_accessor(),
                         end   : prev()
                     }));
                     continue;
@@ -1390,7 +1393,7 @@ function parse($TEXT, options) {
 
     function as_symbol(type, noerror) {
         if (!is("name")) {
-            if (!noerror) croak("SyntaxError: Name expected");
+            if (!noerror) croak("Name expected");
             return null;
         }
         var sym = _make_symbol(type);
@@ -1454,7 +1457,7 @@ function parse($TEXT, options) {
 
     function make_unary(ctor, op, expr) {
         if ((op == "++" || op == "--") && !is_assignable(expr))
-            croak("SyntaxError: Invalid use of " + op + " operator");
+            croak("Invalid use of " + op + " operator", null, ctor === AST_UnaryPrefix ? expr.start.col - 1 : null);
         return new ctor({ operator: op, expression: expr });
     };
 
@@ -1499,9 +1502,8 @@ function parse($TEXT, options) {
     };
 
     function is_assignable(expr) {
-        if (!options.strict) return true;
-        if (expr instanceof AST_This) return false;
-        return (expr instanceof AST_PropAccess || expr instanceof AST_Symbol);
+        if (options.cli) return true;
+        return expr instanceof AST_PropAccess || expr instanceof AST_SymbolRef;
     };
 
     var maybe_assign = function(no_in) {
@@ -1518,7 +1520,7 @@ function parse($TEXT, options) {
                     end      : prev()
                 });
             }
-            croak("SyntaxError: Invalid assignment");
+            croak("Invalid assignment");
         }
         return left;
     };

lib/propmangle.js

@@ -44,7 +44,15 @@
 "use strict";
 
 function find_builtins() {
-    var a = [];
+    // NaN will be included due to Number.NaN
+    var a = [
+        "null",
+        "true",
+        "false",
+        "Infinity",
+        "-Infinity",
+        "undefined",
+    ];
     [ Object, Array, Function, Number,
       String, Boolean, Error, Math,
       Date, RegExp
@@ -62,11 +70,12 @@ function find_builtins() {
 
 function mangle_properties(ast, options) {
     options = defaults(options, {
-        reserved : null,
-        cache : null,
-        only_cache : false,
-        regex : null,
-        ignore_quoted : false
+        cache: null,
+        debug: false,
+        ignore_quoted: false,
+        only_cache: false,
+        regex: null,
+        reserved: null,
     });
 
     var reserved = options.reserved;
@@ -84,29 +93,33 @@ function mangle_properties(ast, options) {
     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) {
-            if (!(ignore_quoted && node.quote))
-                add(node.key);
+            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) {
-            if (this.parent() instanceof AST_Assign) {
-                add(node.property);
-            }
+            add(node.property);
         }
         else if (node instanceof AST_Sub) {
-            if (this.parent() instanceof AST_Assign) {
-                if (!ignore_quoted)
-                    addStrings(node.property);
-            }
+            addStrings(node.property, ignore_quoted);
         }
     }));
 
@@ -149,18 +162,24 @@ function mangle_properties(ast, options) {
         if (options.only_cache) {
             return cache.props.has(name);
         }
-        if (/^[0-9.]+$/.test(name)) return false;
+        if (/^-?[0-9]+(\.[0-9]+)?(e[+-][0-9]+)?$/.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) {
+    function add(name, ignore) {
+        if (ignore) {
+            ignored[name] = true;
+            return;
+        }
+
         if (can_mangle(name))
             push_uniq(names_to_mangle, name);
 
@@ -176,15 +195,31 @@ function mangle_properties(ast, options) {
 
         var mangled = cache.props.get(name);
         if (!mangled) {
-            do {
-                mangled = base54(++cache.cname);
-            } while (!can_mangle(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) {
+    function addStrings(node, ignore) {
         var out = {};
         try {
             (function walk(node){
@@ -194,7 +229,7 @@ function mangle_properties(ast, options) {
                         return true;
                     }
                     if (node instanceof AST_String) {
-                        add(node.value);
+                        add(node.value, ignore);
                         return true;
                     }
                     if (node instanceof AST_Conditional) {

lib/scope.js

@@ -51,7 +51,6 @@ function SymbolDef(scope, index, orig) {
     this.global = false;
     this.mangled_name = null;
     this.undeclared = false;
-    this.constant = false;
     this.index = index;
     this.id = SymbolDef.next_id++;
 };
@@ -76,9 +75,14 @@ SymbolDef.prototype = {
         }
         else if (!this.mangled_name && !this.unmangleable(options)) {
             var s = this.scope;
-            if (!options.screw_ie8 && this.orig[0] instanceof AST_SymbolLambda)
+            var sym = this.orig[0];
+            if (!options.screw_ie8 && sym instanceof AST_SymbolLambda)
                 s = s.parent_scope;
-            this.mangled_name = s.next_mangled(options, this);
+            var def;
+            if (this.defun && (def = this.defun.variables.get(this.name))) {
+                this.mangled_name = def.mangled_name || def.name;
+            } else
+                this.mangled_name = s.next_mangled(options, this);
             if (this.global && cache) {
                 cache.set(this.name, this.mangled_name);
             }
@@ -88,8 +92,8 @@ SymbolDef.prototype = {
 
 AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
     options = defaults(options, {
+        cache: null,
         screw_ie8: true,
-        cache: null
     });
 
     // pass 1: setup scope chaining and handle definitions
@@ -97,26 +101,23 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
     var scope = self.parent_scope = null;
     var labels = new Dictionary();
     var defun = null;
-    var last_var_had_const_pragma = false;
-    var nesting = 0;
     var tw = new TreeWalker(function(node, descend){
-        if (options.screw_ie8 && node instanceof AST_Catch) {
+        if (node instanceof AST_Catch) {
             var save_scope = scope;
             scope = new AST_Scope(node);
-            scope.init_scope_vars(nesting);
-            scope.parent_scope = save_scope;
+            scope.init_scope_vars(save_scope);
             descend();
             scope = save_scope;
             return true;
         }
         if (node instanceof AST_Scope) {
-            node.init_scope_vars(nesting);
-            var save_scope = node.parent_scope = scope;
+            node.init_scope_vars(scope);
+            var save_scope = scope;
             var save_defun = defun;
             var save_labels = labels;
             defun = scope = node;
             labels = new Dictionary();
-            ++nesting; descend(); --nesting;
+            descend();
             scope = save_scope;
             defun = save_defun;
             labels = save_labels;
@@ -155,18 +156,20 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
             // later.
             (node.scope = defun.parent_scope).def_function(node);
         }
-        else if (node instanceof AST_Var) {
-            last_var_had_const_pragma = node.has_const_pragma();
-        }
         else if (node instanceof AST_SymbolVar
-                 || node instanceof AST_SymbolConst) {
-            var def = defun.def_variable(node);
-            def.constant = node instanceof AST_SymbolConst || last_var_had_const_pragma;
-            def.init = tw.parent().value;
+            || node instanceof AST_SymbolConst) {
+            defun.def_variable(node);
+            if (defun !== scope) {
+                node.mark_enclosed(options);
+                var def = scope.find_variable(node);
+                if (node.thedef !== def) {
+                    node.thedef = def;
+                    node.reference(options);
+                }
+            }
         }
         else if (node instanceof AST_SymbolCatch) {
-            (options.screw_ie8 ? scope : defun)
-                .def_variable(node);
+            scope.def_variable(node).defun = defun;
         }
         else if (node instanceof AST_LabelRef) {
             var sym = labels.get(node.name);
@@ -203,64 +206,93 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
                 }
             }
             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;
-                    g.global = true;
-                    globals.set(name, g);
-                }
-                node.thedef = g;
-                if (func && name == "arguments") {
-                    func.uses_arguments = true;
-                }
-            } else {
-                node.thedef = sym;
+            if (node.scope instanceof AST_Lambda && name == "arguments") {
+                node.scope.uses_arguments = true;
             }
-            node.reference();
+            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.defun;
+                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.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
-    this.uses_eval = false;   // will be set to true if this or nested scope uses the global `eval`
-    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_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(parent_scope){
+    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
+    this.uses_eval = false;             // will be set to true if this or nested scope uses the global `eval`
+    this.parent_scope = parent_scope;   // 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
 });
 
 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);
+    this.def_variable(new AST_SymbolVar({
+        name: "arguments",
+        start: this.start,
+        end: this.end
+    }));
 });
 
-AST_SymbolRef.DEFMETHOD("reference", function() {
+AST_Symbol.DEFMETHOD("mark_enclosed", 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_Symbol.DEFMETHOD("reference", function(options) {
+    this.definition().references.push(this);
+    this.mark_enclosed(options);
 });
 
 AST_Scope.DEFMETHOD("find_variable", function(name){
@@ -314,18 +346,17 @@ AST_Function.DEFMETHOD("next_mangled", function(options, def){
     // 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_def && tricky_def.mangled_name == name))
+        if (!tricky_name || tricky_name != name)
             return name;
     }
 });
 
-AST_Scope.DEFMETHOD("references", function(sym){
-    if (sym instanceof AST_Symbol) sym = sym.definition();
-    return this.enclosed.indexOf(sym) < 0 ? null : sym;
-});
-
 AST_Symbol.DEFMETHOD("unmangleable", function(options){
     return this.definition().unmangleable(options);
 });
@@ -365,20 +396,14 @@ AST_Symbol.DEFMETHOD("global", function(){
     return this.definition().global;
 });
 
-AST_Var.DEFMETHOD("has_const_pragma", function() {
-    var comments_before = this.start && this.start.comments_before;
-    var lastComment = comments_before && comments_before[comments_before.length - 1];
-    return lastComment && /@const\b/.test(lastComment.value);
-});
-
 AST_Toplevel.DEFMETHOD("_default_mangler_options", function(options){
     return defaults(options, {
-        except      : [],
         eval        : false,
+        except      : [],
+        keep_fnames : false,
+        screw_ie8   : true,
         sort        : false, // Ignored. Flag retained for backwards compatibility.
         toplevel    : false,
-        screw_ie8   : true,
-        keep_fnames : false
     });
 });
 
@@ -551,12 +576,12 @@ var base54 = (function() {
 
 AST_Toplevel.DEFMETHOD("scope_warnings", function(options){
     options = defaults(options, {
-        undeclared       : false, // this makes a lot of noise
-        unreferenced     : true,
         assign_to_global : true,
+        eval             : true,
         func_arguments   : true,
         nested_defuns    : true,
-        eval             : true
+        undeclared       : false, // this makes a lot of noise
+        unreferenced     : true,
     });
     var tw = new TreeWalker(function(node){
         if (options.undeclared

lib/sourcemap.js

@@ -58,6 +58,16 @@ function SourceMap(options) {
         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({

lib/utils.js

@@ -78,13 +78,28 @@ 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) {
-    Error.call(this, msg);
-    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);
@@ -111,7 +126,11 @@ function merge(obj, ext) {
     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) {
@@ -168,7 +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];
     });
 };
 
@@ -318,3 +337,26 @@ Dictionary.fromObject = function(obj) {
 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;
+        }
+    }
+}

npm-shrinkwrap.json

@@ -1,128 +0,0 @@
-{
-  "name": "uglify-js",
-  "version": "2.4.24",
-  "dependencies": {
-    "abbrev": {
-      "version": "1.0.7",
-      "from": "abbrev@>=1.0.0 <2.0.0",
-      "resolved": "https://registry.npmjs.org/abbrev/-/abbrev-1.0.7.tgz"
-    },
-    "amdefine": {
-      "version": "1.0.0",
-      "from": "amdefine@>=0.0.4",
-      "resolved": "https://registry.npmjs.org/amdefine/-/amdefine-1.0.0.tgz"
-    },
-    "async": {
-      "version": "0.2.10",
-      "from": "async@>=0.2.6 <0.3.0",
-      "resolved": "https://registry.npmjs.org/async/-/async-0.2.10.tgz"
-    },
-    "camelcase": {
-      "version": "1.2.1",
-      "from": "camelcase@>=1.0.2 <2.0.0",
-      "resolved": "https://registry.npmjs.org/camelcase/-/camelcase-1.2.1.tgz"
-    },
-    "decamelize": {
-      "version": "1.0.0",
-      "from": "decamelize@>=1.0.0 <2.0.0",
-      "resolved": "https://registry.npmjs.org/decamelize/-/decamelize-1.0.0.tgz"
-    },
-    "deep-is": {
-      "version": "0.1.3",
-      "from": "deep-is@>=0.1.2 <0.2.0",
-      "resolved": "https://registry.npmjs.org/deep-is/-/deep-is-0.1.3.tgz"
-    },
-    "esprima": {
-      "version": "1.1.1",
-      "from": "esprima@>=1.1.1 <1.2.0",
-      "resolved": "https://registry.npmjs.org/esprima/-/esprima-1.1.1.tgz"
-    },
-    "estraverse": {
-      "version": "1.5.1",
-      "from": "estraverse@>=1.5.1 <1.6.0",
-      "resolved": "https://registry.npmjs.org/estraverse/-/estraverse-1.5.1.tgz"
-    },
-    "esutils": {
-      "version": "1.0.0",
-      "from": "esutils@>=1.0.0 <1.1.0",
-      "resolved": "https://registry.npmjs.org/esutils/-/esutils-1.0.0.tgz"
-    },
-    "fast-levenshtein": {
-      "version": "1.0.7",
-      "from": "fast-levenshtein@>=1.0.0 <1.1.0",
-      "resolved": "https://registry.npmjs.org/fast-levenshtein/-/fast-levenshtein-1.0.7.tgz"
-    },
-    "levn": {
-      "version": "0.2.5",
-      "from": "levn@>=0.2.5 <0.3.0",
-      "resolved": "https://registry.npmjs.org/levn/-/levn-0.2.5.tgz"
-    },
-    "nopt": {
-      "version": "2.1.2",
-      "from": "nopt@>=2.1.2 <2.2.0",
-      "resolved": "https://registry.npmjs.org/nopt/-/nopt-2.1.2.tgz"
-    },
-    "optionator": {
-      "version": "0.5.0",
-      "from": "optionator@>=0.5.0 <0.6.0",
-      "resolved": "https://registry.npmjs.org/optionator/-/optionator-0.5.0.tgz"
-    },
-    "prelude-ls": {
-      "version": "1.1.2",
-      "from": "prelude-ls@>=1.1.1 <1.2.0",
-      "resolved": "https://registry.npmjs.org/prelude-ls/-/prelude-ls-1.1.2.tgz"
-    },
-    "reflect": {
-      "version": "0.1.3",
-      "from": "git://github.com/zaach/reflect.js.git",
-      "resolved": "git://github.com/zaach/reflect.js.git#286bcd79661c96ecc404357d3c0e35fdb54a6967"
-    },
-    "source-map": {
-      "version": "0.5.1",
-      "from": "source-map@>=0.5.1 <0.6.0",
-      "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.5.1.tgz"
-    },
-    "type-check": {
-      "version": "0.3.1",
-      "from": "type-check@>=0.3.1 <0.4.0",
-      "resolved": "https://registry.npmjs.org/type-check/-/type-check-0.3.1.tgz"
-    },
-    "uglify-js": {
-      "version": "2.4.24",
-      "from": "git://github.com/mishoo/UglifyJS2.git",
-      "resolved": "git://github.com/mishoo/UglifyJS2.git#2a06c7758e24a64740473c8031eafbb7fefa213f",
-      "dependencies": {
-        "source-map": {
-          "version": "0.1.34",
-          "from": "source-map@0.1.34",
-          "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.1.34.tgz"
-        }
-      }
-    },
-    "uglify-to-browserify": {
-      "version": "1.0.2",
-      "from": "uglify-to-browserify@>=1.0.0 <1.1.0",
-      "resolved": "https://registry.npmjs.org/uglify-to-browserify/-/uglify-to-browserify-1.0.2.tgz"
-    },
-    "window-size": {
-      "version": "0.1.0",
-      "from": "window-size@0.1.0",
-      "resolved": "https://registry.npmjs.org/window-size/-/window-size-0.1.0.tgz"
-    },
-    "wordwrap": {
-      "version": "0.0.2",
-      "from": "wordwrap@0.0.2",
-      "resolved": "https://registry.npmjs.org/wordwrap/-/wordwrap-0.0.2.tgz"
-    },
-    "yargs": {
-      "version": "3.10.0",
-      "from": "yargs@>=3.10.0 <3.11.0",
-      "resolved": "https://registry.npmjs.org/yargs/-/yargs-3.10.0.tgz"
-    },
-    "zeparser": {
-      "version": "0.0.7",
-      "from": "git://github.com/qfox/ZeParser.git",
-      "resolved": "git://github.com/qfox/ZeParser.git#c99240c5ba7054c467733800ff38265958a2dda9"
-    }
-  }
-}

package.json

@@ -4,7 +4,7 @@
   "homepage": "http://lisperator.net/uglifyjs",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "2.7.0",
+  "version": "2.8.23",
   "engines": {
     "node": ">=0.8.0"
   },
@@ -29,9 +29,7 @@
     "LICENSE"
   ],
   "dependencies": {
-    "async": "~0.2.6",
     "source-map": "~0.5.1",
-    "uglify-to-browserify": "~1.0.0",
     "yargs": "~3.10.0"
   },
   "devDependencies": {
@@ -41,13 +39,15 @@
     "estraverse": "~1.5.1",
     "mocha": "~2.3.4"
   },
+  "optionalDependencies": {
+    "uglify-to-browserify": "~1.0.0"
+  },
   "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-3.2.1.js",
+    "https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.6.4/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/arrays.js

@@ -21,10 +21,19 @@ constant_join: {
     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("");
@@ -33,10 +42,19 @@ constant_join: {
     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 = "";
@@ -72,3 +90,88 @@ constant_join_2: {
         var f = "strstr" + variable + "foobarmoo" + foo;
     }
 }
+
+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/asm.js

@@ -90,13 +90,13 @@ asm_mixed: {
         }
         function no_asm_GeometricMean(stdlib, foreign, buffer) {
             function logSum(start, end) {
-                start = 0 | start, end = 0 | 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 | start, end = 0 | end, +exp(+logSum(start, end) / +(end - start | 0));
+                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/collapse_vars.js

@@ -43,6 +43,7 @@ collapse_vars_side_effects_1: {
                 z = i += 4;
             log(x, z, y, i);
         }
+        f1(), f2(), f3(), f4();
     }
     expect: {
         function f1() {
@@ -73,7 +74,9 @@ collapse_vars_side_effects_1: {
                 y = i += 3;
             log(x, i += 4, y, i);
         }
+        f1(), f2(), f3(), f4();
     }
+    expect_stdout: true
 }
 
 collapse_vars_side_effects_2: {
@@ -338,14 +341,15 @@ collapse_vars_while: {
 collapse_vars_do_while: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
-        comparisons:true, evaluate:true, booleans:false, loops:false, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true
+        comparisons:true, evaluate:true, booleans:false, loops:false, unused:"keep_assign",
+        hoist_funs:true, keep_fargs:true, if_return:true, join_vars:true, cascade:true,
+        side_effects:true
     }
     input: {
         function f1(y) {
-            // The constant do-while condition `c` will be replaced.
+            // The constant do-while condition `c` will not be replaced.
             var c = 9;
-            do { } while (c === 77);
+            do {} while (c === 77);
         }
         function f2(y) {
             // The non-constant do-while condition `c` will not be replaced.
@@ -380,7 +384,8 @@ collapse_vars_do_while: {
     }
     expect: {
         function f1(y) {
-            do ; while (false);
+            var c = 9;
+            do ; while (77 === c);
         }
         function f2(y) {
             var c = 5 - y;
@@ -409,6 +414,80 @@ collapse_vars_do_while: {
     }
 }
 
+collapse_vars_do_while_drop_assign: {
+    options = {
+        collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
+        comparisons:true, evaluate:true, booleans:false, loops:false, unused:true, hoist_funs:true,
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true
+    }
+    input: {
+        function f1(y) {
+            // The constant do-while condition `c` will be not replaced.
+            var c = 9;
+            do {} while (c === 77);
+        }
+        function f2(y) {
+            // The non-constant do-while condition `c` will not be replaced.
+            var c = 5 - y;
+            do { } while (c);
+        }
+        function f3(y) {
+            // The constant `x` will be replaced in the do loop body.
+            function fn(n) { console.log(n); }
+            var a = 2, x = 7;
+            do {
+                fn(a = x);
+                break;
+            } while (y);
+        }
+        function f4(y) {
+            // The non-constant `a` will not be replaced in the do loop body.
+            var a = y / 4;
+            do {
+                return a;
+            } while (y);
+        }
+        function f5(y) {
+            function p(x) { console.log(x); }
+            do {
+                // The non-constant `a` will be replaced in p(a)
+                // because it is declared in same block.
+                var a = y - 3;
+                p(a);
+            } while (--y);
+        }
+    }
+    expect: {
+        function f1(y) {
+            var c = 9;
+            do ; while (77 === c);
+        }
+        function f2(y) {
+            var c = 5 - y;
+            do ; while (c);
+        }
+        function f3(y) {
+            function fn(n) { console.log(n); }
+            do {
+                fn(7);
+                break;
+            } while (y);
+        }
+        function f4(y) {
+            var a = y / 4;
+            do
+                return a;
+            while (y);
+        }
+        function f5(y) {
+            function p(x) { console.log(x); }
+            do {
+                p(y - 3);
+            } while (--y);
+        }
+    }
+}
+
 collapse_vars_seq: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
@@ -567,8 +646,9 @@ collapse_vars_assignment: {
 collapse_vars_lvalues: {
     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
+        comparisons:true, evaluate:true, booleans:true, loops:true, unused:"keep_assign",
+        hoist_funs:true, keep_fargs:true, if_return:true, join_vars:true, cascade:true,
+        side_effects:true
     }
     input: {
         function f0(x) { var i = ++x; return x += i; }
@@ -593,7 +673,38 @@ collapse_vars_lvalues: {
         function f7(x) { var w = e1(), v = e2(), c = v - x; return (w = x) - c; }
         function f8(x) { var w = e1(), v = e2(); return (w = x) - (v - x); }
         function f9(x) { var w = e1(); return e2() - x - (w = x); }
+    }
+}
 
+collapse_vars_lvalues_drop_assign: {
+    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 f0(x) { var i = ++x; return x += i; }
+        function f1(x) { var a = (x -= 3); return x += a; }
+        function f2(x) { var z = x, a = ++z; return z += a; }
+        function f3(x) { var a = (x -= 3), b = x + a; return b; }
+        function f4(x) { var a = (x -= 3); return x + a; }
+        function f5(x) { var w = e1(), v = e2(), c = v = --x, b = w = x; return b - c; }
+        function f6(x) { var w = e1(), v = e2(), c = v = --x, b = w = x; return c - b; }
+        function f7(x) { var w = e1(), v = e2(), c = v - x, b = w = x; return b - c; }
+        function f8(x) { var w = e1(), v = e2(), b = w = x, c = v - x; return b - c; }
+        function f9(x) { var w = e1(), v = e2(), b = w = x, c = v - x; return c - b; }
+    }
+    expect: {
+        function f0(x) { var i = ++x; return x += i; }
+        function f1(x) { var a = (x -= 3); return x += a; }
+        function f2(x) { var z = x, a = ++z; return z += a; }
+        function f3(x) { var a = (x -= 3); return x + a; }
+        function f4(x) { var a = (x -= 3); return x + a; }
+        function f5(x) { var v = (e1(), e2()), c = v = --x; return x - c; }
+        function f6(x) { e1(), e2(); return --x - x; }
+        function f7(x) { var v = (e1(), e2()), c = v - x; return x - c; }
+        function f8(x) { var v = (e1(), e2()); return x - (v - x); }
+        function f9(x) { e1(); return e2() - x - x; }
     }
 }
 
@@ -715,6 +826,7 @@ collapse_vars_repeated: {
             console.log(e + "!");
         })("!");
     }
+    expect_stdout: true
 }
 
 collapse_vars_closures: {
@@ -782,7 +894,8 @@ collapse_vars_unary: {
     }
     expect: {
         function f0(o, p) {
-            delete o[p];
+            var x = o[p];
+            delete x;
         }
         function f1(n) {
             return n > +!!n
@@ -1001,6 +1114,7 @@ collapse_vars_eval_and_with: {
             return function() { with (o) console.log(a) };
         })()();
     }
+    expect_stdout: true
 }
 
 collapse_vars_constants: {
@@ -1035,7 +1149,7 @@ collapse_vars_constants: {
         function f3(x) {
             var b = x.prop;
             sideeffect1();
-            return b + (function() { return -9; })();
+            return b + -9;
         }
     }
 }
@@ -1044,7 +1158,8 @@ collapse_vars_arguments: {
     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
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        toplevel:true
     }
     input: {
         var outer = function() {
@@ -1059,6 +1174,7 @@ collapse_vars_arguments: {
             (function(){console.log(arguments);})(7, 1);
         })();
     }
+    expect_stdout: true
 }
 
 collapse_vars_short_circuit: {
@@ -1203,9 +1319,276 @@ collapse_vars_regexp: {
             };
         }
         (function(){
-            var result, rx = /ab*/g;
-            while (result = rx.exec('acdabcdeabbb'))
+            var result, s = "acdabcdeabbb", rx = /ab*/g;
+            while (result = rx.exec(s))
                 console.log(result[0]);
         })();
     }
+    expect_stdout: true
+}
+
+issue_1537: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var k = '';
+        for (k in {prop: 'val'}){}
+    }
+    expect: {
+        var k = '';
+        for (k in {prop: 'val'});
+    }
+}
+
+issue_1562: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var v = 1, B = 2;
+        for (v in objs) f(B);
+
+        var x = 3, C = 10;
+        while(x + 2) bar(C);
+
+        var y = 4, D = 20;
+        do bar(D); while(y + 2);
+
+        var z = 5, E = 30;
+        for (; f(z + 2) ;) bar(E);
+    }
+    expect: {
+        var v = 1;
+        for (v in objs) f(2);
+
+        var x = 3;
+        while(x + 2) bar(10);
+
+        var y = 4;
+        do bar(20); while(y + 2);
+
+        var z = 5;
+        for (; f(z + 2) ;) bar(30);
+    }
+}
+
+issue_1605_1: {
+    options = {
+        collapse_vars: true,
+        toplevel: false,
+    }
+    input: {
+        function foo(x) {
+            var y = x;
+            return y;
+        }
+        var o = new Object;
+        o.p = 1;
+    }
+    expect: {
+        function foo(x) {
+            return x;
+        }
+        var o = new Object;
+        o.p = 1;
+    }
+}
+
+issue_1605_2: {
+    options = {
+        collapse_vars: true,
+        toplevel: "vars",
+    }
+    input: {
+        function foo(x) {
+            var y = x;
+            return y;
+        }
+        var o = new Object;
+        o.p = 1;
+    }
+    expect: {
+        function foo(x) {
+            return x;
+        }
+        (new Object).p = 1;
+    }
+}
+
+issue_1631_1: {
+    options = {
+        cascade: true,
+        collapse_vars: true,
+        hoist_funs: true,
+        join_vars: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        var pc = 0;
+        function f(x) {
+            pc = 200;
+            return 100;
+        }
+        function x() {
+            var t = f();
+            pc += t;
+            return pc;
+        }
+        console.log(x());
+    }
+    expect: {
+        function f(x) {
+            return pc = 200, 100;
+        }
+        function x() {
+            var t = f();
+            return pc += t;
+        }
+        var pc = 0;
+        console.log(x());
+    }
+    expect_stdout: "300"
+}
+
+issue_1631_2: {
+    options = {
+        cascade: true,
+        collapse_vars: true,
+        hoist_funs: true,
+        join_vars: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        var a = 0, b = 1;
+        function f() {
+            a = 2;
+            return 4;
+        }
+        function g() {
+            var t = f();
+            b = a + t;
+            return b;
+        }
+        console.log(g());
+    }
+    expect: {
+        function f() {
+            return a = 2, 4;
+        }
+        function g() {
+            var t = f();
+            return b = a + t;
+        }
+        var a = 0, b = 1;
+        console.log(g());
+    }
+    expect_stdout: "6"
+}
+
+issue_1631_3: {
+    options = {
+        cascade: true,
+        collapse_vars: true,
+        hoist_funs: true,
+        join_vars: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        function g() {
+            var a = 0, b = 1;
+            function f() {
+                a = 2;
+                return 4;
+            }
+            var t = f();
+            b = a + t;
+            return b;
+        }
+        console.log(g());
+    }
+    expect: {
+        function g() {
+            function f() {
+                return a = 2, 4;
+            }
+            var a = 0, b = 1, t = f();
+            return b = a + t;
+        }
+        console.log(g());
+    }
+    expect_stdout: "6"
+}
+
+var_side_effects_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var print = console.log.bind(console);
+        function foo(x) {
+            var twice = x * 2;
+            print('Foo:', twice);
+        }
+        foo(10);
+    }
+    expect: {
+        var print = console.log.bind(console);
+        function foo(x) {
+            print('Foo:', 2 * x);
+        }
+        foo(10);
+    }
+    expect_stdout: true
+}
+
+var_side_effects_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var print = console.log.bind(console);
+        function foo(x) {
+            var twice = x.y * 2;
+            print('Foo:', twice);
+        }
+        foo({ y: 10 });
+    }
+    expect: {
+        var print = console.log.bind(console);
+        function foo(x) {
+            var twice = 2 * x.y;
+            print('Foo:', twice);
+        }
+        foo({ y: 10 });
+    }
+    expect_stdout: true
+}
+
+var_side_effects_3: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+        unsafe: true,
+    }
+    input: {
+        var print = console.log.bind(console);
+        function foo(x) {
+            var twice = x.y * 2;
+            print('Foo:', twice);
+        }
+        foo({ y: 10 });
+    }
+    expect: {
+        var print = console.log.bind(console);
+        function foo(x) {
+            print('Foo:', 2 * x.y);
+        }
+        foo({ y: 10 });
+    }
+    expect_stdout: true
 }

test/compress/concat-strings.js

@@ -24,3 +24,200 @@ concat_1: {
         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

@@ -50,7 +50,8 @@ ifs_3_should_warn: {
         conditionals : true,
         dead_code    : true,
         evaluate     : true,
-        booleans     : true
+        booleans     : true,
+        side_effects : true,
     };
     input: {
         var x, y;
@@ -135,16 +136,28 @@ ifs_6: {
         comparisons: true
     };
     input: {
-        var x;
+        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;
+        var x, y;
         x = foo || bar || baz || boo ? 20 : 10;
+        x[foo] = y ? 10 : 20;
+        foo ? x[bar] = 10 : x[bar] = 20;
     }
 }
 
@@ -159,10 +172,16 @@ cond_1: {
         } 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);
     }
 }
 
@@ -213,10 +232,16 @@ cond_4: {
         } else {
             do_something();
         }
+        if (some_condition()) {
+            side_effects();
+        } else {
+            side_effects();
+        }
     }
     expect: {
         var do_something;
         some_condition(), do_something();
+        some_condition(), side_effects();
     }
 }
 
@@ -250,7 +275,8 @@ cond_5: {
 cond_7: {
     options = {
         conditionals: true,
-        evaluate    : true
+        evaluate    : true,
+        side_effects: true,
     };
     input: {
         var x, y, z, a, b;
@@ -635,166 +661,6 @@ ternary_boolean_alternative: {
     }
 }
 
-conditional_and: {
-    options = {
-        conditionals: true,
-        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;
-    }
-}
-
-conditional_or: {
-    options = {
-        conditionals: true,
-        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;
-    }
-}
-
 trivial_boolean_ternary_expressions : {
     options = {
         conditionals: true,
@@ -874,6 +740,7 @@ issue_1154: {
         conditionals: true,
         evaluate    : true,
         booleans    : true,
+        side_effects: true,
     };
     input: {
         function f1(x) { return x ? -1 : -1; }
@@ -902,7 +769,249 @@ issue_1154: {
         function g2() { return g(), 2; }
         function g3() { return g(), -4; }
         function g4() { return g(), !1; }
-        function g5() { return g(), void 0; }
+        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
+}
+
+issue_1645_1: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        var a = 100, b = 10;
+        (b = a) ? a++ + (b += a) ? b += a : b += a : b ^= a;
+        console.log(a, b);
+    }
+    expect: {
+        var a = 100, b = 10;
+        (b = a) ? (a++ + (b += a), b += a) : b ^= a;
+        console.log(a,b);
+    }
+    expect_stdout: true
+}
+
+issue_1645_2: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        var a = 0;
+        function f() {
+            return a++;
+        }
+        f() ? a += 2 : a += 4;
+        console.log(a);
+    }
+    expect: {
+        var a = 0;
+        function f(){
+            return a++;
+        }
+        f() ? a += 2 : a += 4;
+        console.log(a);
+    }
+    expect_stdout: true
+}
+
+condition_symbol_matches_consequent: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        function foo(x, y) {
+            return x ? x : y;
+        }
+        function bar() {
+            return g ? g : h;
+        }
+        var g = 4;
+        var h = 5;
+        console.log(foo(3, null), foo(0, 7), foo(true, false), bar());
+    }
+    expect: {
+        function foo(x, y) {
+            return x || y;
+        }
+        function bar() {
+            return g || h;
+        }
+        var g = 4;
+        var h = 5;
+        console.log(foo(3, null), foo(0, 7), foo(true, false), bar());
+    }
+    expect_stdout: "3 7 true 4"
+}
+
+delete_conditional_1: {
+    options = {
+        booleans: true,
+        conditionals: true,
+        evaluate: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(delete (1 ? undefined : x));
+        console.log(delete (1 ? void 0 : x));
+        console.log(delete (1 ? Infinity : x));
+        console.log(delete (1 ? 1 / 0 : x));
+        console.log(delete (1 ? NaN : x));
+        console.log(delete (1 ? 0 / 0 : x));
+    }
+    expect: {
+        console.log((void 0, !0));
+        console.log((void 0, !0));
+        console.log((1 / 0, !0));
+        console.log((1 / 0, !0));
+        console.log((NaN, !0));
+        console.log((NaN, !0));
+    }
+    expect_stdout: true
+}
+
+delete_conditional_2: {
+    options = {
+        booleans: true,
+        conditionals: true,
+        evaluate: true,
+        keep_infinity: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(delete (0 ? x : undefined));
+        console.log(delete (0 ? x : void 0));
+        console.log(delete (0 ? x : Infinity));
+        console.log(delete (0 ? x : 1 / 0));
+        console.log(delete (0 ? x : NaN));
+        console.log(delete (0 ? x : 0 / 0));
+    }
+    expect: {
+        console.log((void 0, !0));
+        console.log((void 0, !0));
+        console.log((Infinity, !0));
+        console.log((1 / 0, !0));
+        console.log((NaN, !0));
+        console.log((NaN, !0));
+    }
+    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"))) {
@@ -86,6 +87,7 @@ dead_code_constant_boolean_should_warn_more: {
         var x = 10, y;
         var moo;
     }
+    expect_stdout: true
 }
 
 dead_code_const_declaration: {
@@ -94,7 +96,8 @@ dead_code_const_declaration: {
         loops        : true,
         booleans     : true,
         conditionals : true,
-        evaluate     : true
+        evaluate     : true,
+        reduce_vars  : true,
     };
     input: {
         var unused;
@@ -111,6 +114,7 @@ dead_code_const_declaration: {
         var moo;
         function bar() {}
     }
+    expect_stdout: true
 }
 
 dead_code_const_annotation: {
@@ -119,7 +123,9 @@ dead_code_const_annotation: {
         loops        : true,
         booleans     : true,
         conditionals : true,
-        evaluate     : true
+        evaluate     : true,
+        reduce_vars  : true,
+        toplevel     : true,
     };
     input: {
         var unused;
@@ -136,6 +142,7 @@ dead_code_const_annotation: {
         var moo;
         function bar() {}
     }
+    expect_stdout: true
 }
 
 dead_code_const_annotation_regex: {
@@ -159,6 +166,7 @@ dead_code_const_annotation_regex: {
         var CONST_FOO_ANN = !1;
         CONST_FOO_ANN && console.log('reachable');
     }
+    expect_stdout: true
 }
 
 dead_code_const_annotation_complex_scope: {
@@ -167,7 +175,9 @@ dead_code_const_annotation_complex_scope: {
         loops        : true,
         booleans     : true,
         conditionals : true,
-        evaluate     : true
+        evaluate     : true,
+        reduce_vars  : true,
+        toplevel     : true,
     };
     input: {
         var unused_var;
@@ -201,6 +211,48 @@ dead_code_const_annotation_complex_scope: {
         var beef = 'good';
         var meat = 'beef';
         var pork = 'bad';
-        'good' === pork && console.log('reached, not const');
     }
+    expect_stdout: true
+}
+
+try_catch_finally: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+    }
+    input: {
+        var a = 1;
+        !function() {
+            try {
+                if (false) throw x;
+            } catch (a) {
+                var a = 2;
+                console.log("FAIL");
+            } finally {
+                a = 3;
+                console.log("PASS");
+            }
+        }();
+        try {
+            console.log(a);
+        } finally {
+        }
+    }
+    expect: {
+        var a = 1;
+        !function() {
+            var a;
+            a = 3;
+            console.log("PASS");
+        }();
+        try {
+            console.log(a);
+        } finally {
+        }
+    }
+    expect_stdout: [
+        "PASS",
+        "1",
+    ]
 }

test/compress/drop-console.js

@@ -10,7 +10,7 @@ drop_console_1: {
     }
 }
 
-drop_console_1: {
+drop_console_2: {
     options = { drop_console: true };
     input: {
         console.log('foo');

test/compress/drop-unused.js

@@ -177,3 +177,890 @@ keep_fnames: {
         }
     }
 }
+
+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) {});
+                })();
+            })();
+        }
+    }
+}
+
+issue_1656: {
+    options = {
+        toplevel: true,
+        unused: true,
+    }
+    beautify = {
+        beautify: true,
+    }
+    input: {
+        for(var a=0;;);
+    }
+    expect_exact: "for (;;) ;"
+}
+
+issue_1709: {
+    options = {
+        unused: true,
+    }
+    input: {
+        console.log(
+            function x() {
+                var x = 1;
+                return x;
+            }(),
+            function y() {
+                const y = 2;
+                return y;
+            }(),
+            function z() {
+                function z() {}
+                return z;
+            }()
+        );
+    }
+    expect: {
+        console.log(
+            function() {
+                var x = 1;
+                return x;
+            }(),
+            function() {
+                const y = 2;
+                return y;
+            }(),
+            function() {
+                function z() {}
+                return z;
+            }()
+        );
+    }
+    expect_stdout: true
+}
+
+issue_1715_1: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        function f() {
+            a++;
+            try {
+                x();
+            } catch (a) {
+                var a;
+            }
+        }
+        f();
+        console.log(a);
+    }
+    expect: {
+        var a = 1;
+        function f() {
+            a++;
+            try {
+                x();
+            } catch (a) {
+                var a;
+            }
+        }
+        f();
+        console.log(a);
+    }
+    expect_stdout: "1"
+}
+
+issue_1715_2: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        function f() {
+            a++;
+            try {
+                x();
+            } catch (a) {
+                var a = 2;
+            }
+        }
+        f();
+        console.log(a);
+    }
+    expect: {
+        var a = 1;
+        function f() {
+            a++;
+            try {
+                x();
+            } catch (a) {
+                var a;
+            }
+        }
+        f();
+        console.log(a);
+    }
+    expect_stdout: "1"
+}
+
+issue_1715_3: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        function f() {
+            a++;
+            try {
+                console;
+            } catch (a) {
+                var a = 2 + x();
+            }
+        }
+        f();
+        console.log(a);
+    }
+    expect: {
+        var a = 1;
+        function f() {
+            a++;
+            try {
+                console;
+            } catch (a) {
+                var a = x();
+            }
+        }
+        f();
+        console.log(a);
+    }
+    expect_stdout: "1"
+}
+
+issue_1715_4: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        !function a() {
+            a++;
+            try {
+                x();
+            } catch (a) {
+                var a;
+            }
+        }();
+        console.log(a);
+    }
+    expect: {
+        var a = 1;
+        !function() {
+            a++;
+            try {
+                x();
+            } catch (a) {
+                var a;
+            }
+        }();
+        console.log(a);
+    }
+    expect_stdout: "1"
+}
+
+delete_assign_1: {
+    options = {
+        booleans: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        console.log(delete (a = undefined));
+        console.log(delete (a = void 0));
+        console.log(delete (a = Infinity));
+        console.log(delete (a = 1 / 0));
+        console.log(delete (a = NaN));
+        console.log(delete (a = 0 / 0));
+    }
+    expect: {
+        console.log((void 0, !0));
+        console.log((void 0, !0));
+        console.log((1 / 0, !0));
+        console.log((1 / 0, !0));
+        console.log((NaN, !0));
+        console.log((0 / 0, !0));
+    }
+    expect_stdout: true
+}
+
+delete_assign_2: {
+    options = {
+        booleans: true,
+        keep_infinity: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        console.log(delete (a = undefined));
+        console.log(delete (a = void 0));
+        console.log(delete (a = Infinity));
+        console.log(delete (a = 1 / 0));
+        console.log(delete (a = NaN));
+        console.log(delete (a = 0 / 0));
+    }
+    expect: {
+        console.log((void 0, !0));
+        console.log((void 0, !0));
+        console.log((Infinity, !0));
+        console.log((1 / 0, !0));
+        console.log((NaN, !0));
+        console.log((0 / 0, !0));
+    }
+    expect_stdout: true
+}
+
+issue_1830_1: {
+    options = {
+        unused: true,
+    }
+    input: {
+        !function() {
+            L: for (var b = console.log(1); !1;) continue L;
+        }();
+    }
+    expect: {
+        !function() {
+            L: for (console.log(1); !1;) continue L;
+        }();
+    }
+    expect_stdout: "1"
+}
+
+issue_1830_2: {
+    options = {
+        unused: true,
+    }
+    input: {
+        !function() {
+            L: for (var a = 1, b = console.log(a); --a;) continue L;
+        }();
+    }
+    expect: {
+        !function() {
+            var a = 1;
+            L: for (console.log(a); --a;) continue L;
+        }();
+    }
+    expect_stdout: "1"
+}

test/compress/evaluate.js

@@ -1,3 +1,187 @@
+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: {
@@ -12,10 +196,11 @@ negative_zero: {
         console.log(
             -0,
             0,
-            1 / (-0),
-            1 / (-0)
+            -1/0,
+            -1/0
         );
     }
+    expect_stdout: true
 }
 
 positive_zero: {
@@ -32,8 +217,775 @@ positive_zero: {
         console.log(
             0,
             -0,
-            1 / (0),
-            1 / (0)
+            1/0,
+            1/0
+        );
+    }
+    expect_stdout: true
+}
+
+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)
         );
     }
 }
+
+issue_1649: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log(-1 + -1);
+    }
+    expect: {
+        console.log(-2);
+    }
+    expect_stdout: "-2";
+}
+
+issue_1760_1: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        !function(a) {
+            try {
+                throw 0;
+            } catch (NaN) {
+                a = +"foo";
+            }
+            console.log(a);
+        }();
+    }
+    expect: {
+        !function(a) {
+            try {
+                throw 0;
+            } catch (NaN) {
+                a = 0 / 0;
+            }
+            console.log(a);
+        }();
+    }
+    expect_stdout: "NaN"
+}
+
+issue_1760_2: {
+    options = {
+        evaluate: true,
+        keep_infinity: true,
+    }
+    input: {
+        !function(a) {
+            try {
+                throw 0;
+            } catch (Infinity) {
+                a = 123456789 / 0;
+            }
+            console.log(a);
+        }();
+    }
+    expect: {
+        !function(a) {
+            try {
+                throw 0;
+            } catch (Infinity) {
+                a = 1 / 0;
+            }
+            console.log(a);
+        }();
+    }
+    expect_stdout: "Infinity"
+}
+
+delete_expr_1: {
+    options = {
+        booleans: true,
+        evaluate: true,
+    }
+    input: {
+        console.log(delete undefined);
+        console.log(delete void 0);
+        console.log(delete Infinity);
+        console.log(delete (1 / 0));
+        console.log(delete NaN);
+        console.log(delete (0 / 0));
+    }
+    expect: {
+        console.log(delete undefined);
+        console.log((void 0, !0));
+        console.log(delete Infinity);
+        console.log((1 / 0, !0));
+        console.log(delete NaN);
+        console.log((0 / 0, !0));
+    }
+    expect_stdout: true
+}
+
+delete_expr_2: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        keep_infinity: true,
+    }
+    input: {
+        console.log(delete undefined);
+        console.log(delete void 0);
+        console.log(delete Infinity);
+        console.log(delete (1 / 0));
+        console.log(delete NaN);
+        console.log(delete (0 / 0));
+    }
+    expect: {
+        console.log(delete undefined);
+        console.log((void 0, !0));
+        console.log(delete Infinity);
+        console.log((1 / 0, !0));
+        console.log(delete NaN);
+        console.log((0 / 0, !0));
+    }
+    expect_stdout: true
+}
+
+delete_binary_1: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(delete (true && undefined));
+        console.log(delete (true && void 0));
+        console.log(delete (true && Infinity));
+        console.log(delete (true && (1 / 0)));
+        console.log(delete (true && NaN));
+        console.log(delete (true && (0 / 0)));
+    }
+    expect: {
+        console.log((void 0, !0));
+        console.log((void 0, !0));
+        console.log((1 / 0, !0));
+        console.log((1 / 0, !0));
+        console.log((NaN, !0));
+        console.log((NaN, !0));
+    }
+    expect_stdout: true
+}
+
+delete_binary_2: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        keep_infinity: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(delete (false || undefined));
+        console.log(delete (false || void 0));
+        console.log(delete (false || Infinity));
+        console.log(delete (false || (1 / 0)));
+        console.log(delete (false || NaN));
+        console.log(delete (false || (0 / 0)));
+    }
+    expect: {
+        console.log((void 0, !0));
+        console.log((void 0, !0));
+        console.log((Infinity, !0));
+        console.log((1 / 0, !0));
+        console.log((NaN, !0));
+        console.log((NaN, !0));
+    }
+    expect_stdout: true
+}
+
+Infinity_NaN_undefined_LHS: {
+    beautify = {
+        beautify: true,
+    }
+    input: {
+        function f() {
+            Infinity = Infinity;
+            ++Infinity;
+            Infinity--;
+            NaN *= NaN;
+            ++NaN;
+            NaN--;
+            undefined |= undefined;
+            ++undefined;
+            undefined--;
+        }
+    }
+    expect_exact: [
+        "function f() {",
+        "    Infinity = 1 / 0;",
+        "    ++Infinity;",
+        "    Infinity--;",
+        "    NaN *= NaN;",
+        "    ++NaN;",
+        "    NaN--;",
+        "    undefined |= void 0;",
+        "    ++undefined;",
+        "    undefined--;",
+        "}",
+    ]
+}

test/compress/functions.js

@@ -0,0 +1,149 @@
+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;
+    }
+}
+
+issue_1841_1: {
+    options = {
+        keep_fargs: false,
+        pure_getters: "strict",
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        var b = 10;
+        !function(arg) {
+            for (var key in "hi")
+                var n = arg.baz, n = [ b = 42 ];
+        }(--b);
+        console.log(b);
+    }
+    expect: {
+        var b = 10;
+        !function() {
+            for (var key in "hi") {
+                b = 42;
+            }
+        }(--b);
+        console.log(b);
+    }
+    expect_exact: "42"
+}
+
+issue_1841_2: {
+    options = {
+        keep_fargs: false,
+        pure_getters: false,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        var b = 10;
+        !function(arg) {
+            for (var key in "hi")
+                var n = arg.baz, n = [ b = 42 ];
+        }(--b);
+        console.log(b);
+    }
+    expect: {
+        var b = 10;
+        !function(arg) {
+            for (var key in "hi") {
+                arg.baz, b = 42;
+            }
+        }(--b);
+        console.log(b);
+    }
+    expect_exact: "42"
+}

test/compress/global_defs.js

@@ -0,0 +1,162 @@
+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]',
+    ]
+}
+
+issue_1801: {
+    options = {
+        booleans: true,
+        global_defs: {
+            "CONFIG.FOO.BAR": true,
+        },
+    }
+    input: {
+        console.log(CONFIG.FOO.BAR);
+    }
+    expect: {
+        console.log(!0);
+    }
+}

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

@@ -47,22 +47,6 @@ html_comment_in_greater_than_or_equal: {
     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-->"; }

test/compress/if_return.js

@@ -170,8 +170,51 @@ if_return_7: {
         }
     }
     expect: {
-        // suboptimal
-        function f(x){return!!x||(foo(),void bar())}
+        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)}
     }
 }
 
@@ -205,3 +248,57 @@ issue_1089: {
         }
     }
 }
+
+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-1034.js

@@ -39,7 +39,7 @@ non_hoisted_function_after_return_2a: {
         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
+        collapse_vars: false, passes: 2, warnings: "verbose"
     }
     input: {
         function foo(x) {
@@ -75,7 +75,7 @@ non_hoisted_function_after_return_2a: {
         "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]"
+        "WARN: Dropping unused variable c [test/compress/issue-1034.js:53,16]",
     ]
 }
 
@@ -114,8 +114,5 @@ non_hoisted_function_after_return_2b: {
         "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

@@ -13,7 +13,8 @@ const_declaration: {
 
 const_pragma: {
     options = {
-        evaluate: true
+        evaluate: true,
+        reduce_vars: true,
     };
 
     input: {
@@ -27,7 +28,8 @@ const_pragma: {
 // for completeness' sake
 not_const: {
     options = {
-        evaluate: true
+        evaluate: true,
+        reduce_vars: true,
     };
 
     input: {

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-1105.js

@@ -193,13 +193,15 @@ assorted_Infinity_NaN_undefined_in_with_scope: {
         cascade:       true,
         side_effects:  true,
         sequences:     false,
+        keep_infinity: false,
     }
     input: {
+        var f = console.log;
         var o = {
             undefined : 3,
             NaN       : 4,
             Infinity  : 5,
-        }
+        };
         if (o) {
             f(undefined, void 0);
             f(NaN, 0/0);
@@ -216,25 +218,88 @@ assorted_Infinity_NaN_undefined_in_with_scope: {
         }
     }
     expect: {
-        var o = {
+        var f = console.log, 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(-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(-Infinity, -1/0);
             f(9 + undefined, 9 + void 0);
         }
     }
+    expect_stdout: true
 }
 
+assorted_Infinity_NaN_undefined_in_with_scope_keep_infinity: {
+    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,
+        keep_infinity: true,
+    }
+    input: {
+        var f = console.log;
+        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 f = console.log, o = {
+            undefined : 3,
+            NaN       : 4,
+            Infinity  : 5
+        };
+        if (o) {
+            f(void 0, void 0);
+            f(NaN, NaN);
+            f(Infinity, 1/0);
+            f(-Infinity, -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);
+        }
+    }
+    expect_stdout: true
+}

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-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: Condition left of || 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: Condition left of && 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-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 +1,55 @@
+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() {
+            (function() {
+                var c, b = "long piece of string";
+                c = f(b);
+                c.bar = b;
+            })();
+        })();
+    }
+}

test/compress/issue-1639.js

@@ -0,0 +1,88 @@
+
+issue_1639_1: {
+    options = {
+        booleans: true,
+        cascade: true,
+        conditionals: true,
+        evaluate: true,
+        join_vars: true,
+        loops: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        var a = 100, b = 10;
+
+        var L1 = 5;
+        while (--L1 > 0) {
+            if ((--b), false) {
+                if (b) {
+                    var ignore = 0;
+                }
+            }
+        }
+
+        console.log(a, b);
+    }
+    expect: {
+        for (var a = 100, b = 10, L1 = 5; --L1 > 0;)
+            if (--b, !1) var ignore = 0;
+        console.log(a, b);
+    }
+    expect_stdout: true
+}
+
+issue_1639_2: {
+    options = {
+        booleans: true,
+        cascade: true,
+        conditionals: true,
+        evaluate: true,
+        join_vars: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        var a = 100, b = 10;
+
+        function f19() {
+            if (++a, false)
+                if (a)
+                    if (++a);
+        }
+        f19();
+
+        console.log(a, b);
+    }
+    expect: {
+        var a = 100, b = 10;
+        function f19() {
+            ++a, 1;
+        }
+        f19(),
+        console.log(a, b);
+    }
+    expect_stdout: true
+}
+
+issue_1639_3: {
+    options = {
+        booleans: true,
+        cascade: true,
+        conditionals: true,
+        evaluate: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        var a = 100, b = 10;
+        a++ && false && a ? 0 : 0;
+        console.log(a, b);
+    }
+    expect: {
+        var a = 100, b = 10;
+        a++,
+        console.log(a, b);
+    }
+    expect_stdout: true
+}

test/compress/issue-1656.js

@@ -0,0 +1,45 @@
+f7: {
+    options = {
+        booleans: true,
+        cascade: true,
+        collapse_vars: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        drop_debugger: true,
+        evaluate: true,
+        hoist_funs: true,
+        if_return: true,
+        join_vars: true,
+        loops: true,
+        negate_iife: true,
+        passes: 3,
+        properties: true,
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    beautify = {
+        beautify: true,
+    }
+    input: {
+        var a = 100, b = 10;
+        function f22464() {
+            var brake146670 = 5;
+            while (((b = a) ? !a : ~a ? null : b += a) && --brake146670 > 0) {
+            }
+        }
+        f22464();
+        console.log(a, b);
+    }
+    expect_exact: [
+        "var b = 10;",
+        "",
+        "!function() {",
+        "    for (;b = 100, !1; ) ;",
+        "}(), console.log(100, b);",
+    ]
+    expect_stdout: true
+}

test/compress/issue-1673.js

@@ -0,0 +1,161 @@
+side_effects_catch: {
+    options = {
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                try {
+                    throw 0;
+                } catch (e) {
+                    console.log("PASS");
+                }
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        function f() {
+            (function() {
+                try {
+                    throw 0;
+                } catch (e) {
+                    console.log("PASS");
+                }
+            })();
+        }
+        f();
+    }
+    expect_stdout: "PASS"
+}
+
+side_effects_else: {
+    options = {
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f(x) {
+            function g() {
+                if (x);
+                else console.log("PASS");
+            }
+            g();
+        }
+        f(0);
+    }
+    expect: {
+        function f(x) {
+            (function() {
+                if (x);
+                else console.log("PASS");
+            })();
+        }
+        f(0);
+    }
+    expect_stdout: "PASS"
+}
+
+side_effects_finally: {
+    options = {
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                try {
+                    x();
+                } catch (e) {
+                } finally {
+                    console.log("PASS");
+                }
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        function f() {
+            (function() {
+                try {
+                    x();
+                } catch (e) {
+                } finally {
+                    console.log("PASS");
+                }
+            })();
+        }
+        f();
+    }
+    expect_stdout: "PASS"
+}
+
+side_effects_label: {
+    options = {
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f(x) {
+            function g() {
+                L: {
+                    console.log("PASS");
+                    break L;
+                }
+            }
+            g();
+        }
+        f(0);
+    }
+    expect: {
+        function f(x) {
+            (function() {
+                L: {
+                    console.log("PASS");
+                    break L;
+                }
+            })();
+        }
+        f(0);
+    }
+    expect_stdout: "PASS"
+}
+
+side_effects_switch: {
+    options = {
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                switch (0) {
+                  default:
+                  case console.log("PASS"):
+                }
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        function f() {
+            (function() {
+                switch (0) {
+                  default:
+                  case console.log("PASS"):
+                }
+            })();
+        }
+        f();
+    }
+    expect_stdout: "PASS"
+}

test/compress/issue-1704.js

@@ -0,0 +1,347 @@
+mangle_catch: {
+    options = {
+        screw_ie8: true,
+        toplevel: false,
+    }
+    mangle = {
+        screw_ie8: true,
+        toplevel: false,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            throw 1;
+        } catch (args) {
+            a = "PASS";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var a="FAIL";try{throw 1}catch(o){a="PASS"}console.log(a);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_ie8: {
+    options = {
+        screw_ie8: false,
+        toplevel: false,
+    }
+    mangle = {
+        screw_ie8: false,
+        toplevel: false,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            throw 1;
+        } catch (args) {
+            a = "PASS";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var a="FAIL";try{throw 1}catch(args){a="PASS"}console.log(a);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_var: {
+    options = {
+        screw_ie8: true,
+        toplevel: false,
+    }
+    mangle = {
+        screw_ie8: true,
+        toplevel: false,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            throw 1;
+        } catch (args) {
+            var a = "PASS";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var a="FAIL";try{throw 1}catch(o){var a="PASS"}console.log(a);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_var_ie8: {
+    options = {
+        screw_ie8: false,
+        toplevel: false,
+    }
+    mangle = {
+        screw_ie8: false,
+        toplevel: false,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            throw 1;
+        } catch (args) {
+            var a = "PASS";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var a="FAIL";try{throw 1}catch(args){var a="PASS"}console.log(a);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_toplevel: {
+    options = {
+        screw_ie8: true,
+        toplevel: true,
+    }
+    mangle = {
+        screw_ie8: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            throw 1;
+        } catch (args) {
+            a = "PASS";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var o="FAIL";try{throw 1}catch(c){o="PASS"}console.log(o);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_ie8_toplevel: {
+    options = {
+        screw_ie8: false,
+        toplevel: true,
+    }
+    mangle = {
+        screw_ie8: false,
+        toplevel: true,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            throw 1;
+        } catch (args) {
+            a = "PASS";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var o="FAIL";try{throw 1}catch(c){o="PASS"}console.log(o);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_var_toplevel: {
+    options = {
+        screw_ie8: true,
+        toplevel: true,
+    }
+    mangle = {
+        screw_ie8: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            throw 1;
+        } catch (args) {
+            var a = "PASS";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var o="FAIL";try{throw 1}catch(r){var o="PASS"}console.log(o);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_var_ie8_toplevel: {
+    options = {
+        screw_ie8: false,
+        toplevel: true,
+    }
+    mangle = {
+        screw_ie8: false,
+        toplevel: true,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            throw 1;
+        } catch (args) {
+            var a = "PASS";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var o="FAIL";try{throw 1}catch(r){var o="PASS"}console.log(o);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_redef_1: {
+    options = {
+        screw_ie8: true,
+        toplevel: false,
+    }
+    mangle = {
+        screw_ie8: true,
+        toplevel: false,
+    }
+    input: {
+        var a = "PASS";
+        try {
+            throw "FAIL1";
+        } catch (a) {
+            var a = "FAIL2";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var a="PASS";try{throw"FAIL1"}catch(a){var a="FAIL2"}console.log(a);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_redef_1_ie8: {
+    options = {
+        screw_ie8: false,
+        toplevel: false,
+    }
+    mangle = {
+        screw_ie8: false,
+        toplevel: false,
+    }
+    input: {
+        var a = "PASS";
+        try {
+            throw "FAIL1";
+        } catch (a) {
+            var a = "FAIL2";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var a="PASS";try{throw"FAIL1"}catch(a){var a="FAIL2"}console.log(a);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_redef_1_toplevel: {
+    options = {
+        screw_ie8: true,
+        toplevel: true,
+    }
+    mangle = {
+        screw_ie8: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "PASS";
+        try {
+            throw "FAIL1";
+        } catch (a) {
+            var a = "FAIL2";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var o="PASS";try{throw"FAIL1"}catch(o){var o="FAIL2"}console.log(o);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_redef_1_ie8_toplevel: {
+    options = {
+        screw_ie8: false,
+        toplevel: true,
+    }
+    mangle = {
+        screw_ie8: false,
+        toplevel: true,
+    }
+    input: {
+        var a = "PASS";
+        try {
+            throw "FAIL1";
+        } catch (a) {
+            var a = "FAIL2";
+        }
+        console.log(a);
+    }
+    expect_exact: 'var o="PASS";try{throw"FAIL1"}catch(o){var o="FAIL2"}console.log(o);'
+    expect_stdout: "PASS"
+}
+
+mangle_catch_redef_2: {
+    options = {
+        screw_ie8: true,
+        toplevel: false,
+    }
+    mangle = {
+        screw_ie8: true,
+        toplevel: false,
+    }
+    input: {
+        try {
+            throw "FAIL1";
+        } catch (a) {
+            var a = "FAIL2";
+        }
+        console.log(a);
+    }
+    expect_exact: 'try{throw"FAIL1"}catch(a){var a="FAIL2"}console.log(a);'
+    expect_stdout: "undefined"
+}
+
+mangle_catch_redef_2_ie8: {
+    options = {
+        screw_ie8: false,
+        toplevel: false,
+    }
+    mangle = {
+        screw_ie8: false,
+        toplevel: false,
+    }
+    input: {
+        try {
+            throw "FAIL1";
+        } catch (a) {
+            var a = "FAIL2";
+        }
+        console.log(a);
+    }
+    expect_exact: 'try{throw"FAIL1"}catch(a){var a="FAIL2"}console.log(a);'
+    expect_stdout: "undefined"
+}
+
+mangle_catch_redef_2_toplevel: {
+    options = {
+        screw_ie8: true,
+        toplevel: true,
+    }
+    mangle = {
+        screw_ie8: true,
+        toplevel: true,
+    }
+    input: {
+        try {
+            throw "FAIL1";
+        } catch (a) {
+            var a = "FAIL2";
+        }
+        console.log(a);
+    }
+    expect_exact: 'try{throw"FAIL1"}catch(o){var o="FAIL2"}console.log(o);'
+    expect_stdout: "undefined"
+}
+
+mangle_catch_redef_2_ie8_toplevel: {
+    options = {
+        screw_ie8: false,
+        toplevel: true,
+    }
+    mangle = {
+        screw_ie8: false,
+        toplevel: true,
+    }
+    input: {
+        try {
+            throw "FAIL1";
+        } catch (a) {
+            var a = "FAIL2";
+        }
+        console.log(a);
+    }
+    expect_exact: 'try{throw"FAIL1"}catch(o){var o="FAIL2"}console.log(o);'
+    expect_stdout: "undefined"
+}

test/compress/issue-1733.js

@@ -0,0 +1,97 @@
+function_iife_catch: {
+    mangle = {
+        screw_ie8: true,
+    }
+    input: {
+        function f(n) {
+            !function() {
+                try {
+                    throw 0;
+                } catch (n) {
+                    var a = 1;
+                    console.log(n, a);
+                }
+            }();
+        }
+        f();
+    }
+    expect_exact: "function f(o){!function(){try{throw 0}catch(c){var o=1;console.log(c,o)}}()}f();"
+    expect_stdout: "0 1"
+}
+
+function_iife_catch_ie8: {
+    mangle = {
+        screw_ie8: false,
+    }
+    input: {
+        function f(n) {
+            !function() {
+                try {
+                    throw 0;
+                } catch (n) {
+                    var a = 1;
+                    console.log(n, a);
+                }
+            }();
+        }
+        f();
+    }
+    expect_exact: "function f(o){!function(){try{throw 0}catch(o){var c=1;console.log(o,c)}}()}f();"
+    expect_stdout: "0 1"
+}
+
+function_catch_catch: {
+    mangle = {
+        screw_ie8: true,
+    }
+    input: {
+        var o = 0;
+        function f() {
+            try {
+                throw 1;
+            } catch (c) {
+                try {
+                    throw 2;
+                } catch (o) {
+                    var o = 3;
+                    console.log(o);
+                }
+            }
+            console.log(o);
+        }
+        f();
+    }
+    expect_exact: "var o=0;function f(){try{throw 1}catch(c){try{throw 2}catch(o){var o=3;console.log(o)}}console.log(o)}f();"
+    expect_stdout: [
+        "3",
+        "undefined",
+    ]
+}
+
+function_catch_catch_ie8: {
+    mangle = {
+        screw_ie8: false,
+    }
+    input: {
+        var o = 0;
+        function f() {
+            try {
+                throw 1;
+            } catch (c) {
+                try {
+                    throw 2;
+                } catch (o) {
+                    var o = 3;
+                    console.log(o);
+                }
+            }
+            console.log(o);
+        }
+        f();
+    }
+    expect_exact: "var o=0;function f(){try{throw 1}catch(c){try{throw 2}catch(o){var o=3;console.log(o)}}console.log(o)}f();"
+    expect_stdout: [
+        "3",
+        "undefined",
+    ]
+}

test/compress/issue-1750.js

@@ -0,0 +1,54 @@
+case_1: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        switches: true,
+    }
+    input: {
+        var a = 0, b = 1;
+        switch (true) {
+          case a, true:
+          default:
+            b = 2;
+          case true:
+        }
+        console.log(a, b);
+    }
+    expect: {
+        var a = 0, b = 1;
+        switch (true) {
+          case a, true:
+            b = 2;
+        }
+        console.log(a, b);
+    }
+    expect_stdout: "0 2"
+}
+
+case_2: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        switches: true,
+    }
+    input: {
+        var a = 0, b = 1;
+        switch (0) {
+          default:
+            b = 2;
+          case a:
+            a = 3;
+          case 0:
+        }
+        console.log(a, b);
+    }
+    expect: {
+        var a = 0, b = 1;
+        switch (0) {
+          case a:
+            a = 3;
+        }
+        console.log(a, b);
+    }
+    expect_stdout: "3 1"
+}

test/compress/issue-1770.js

@@ -0,0 +1,239 @@
+mangle_props: {
+    mangle_props = {}
+    input: {
+        var obj = {
+            undefined: 1,
+            NaN: 2,
+            Infinity: 3,
+            "-Infinity": 4,
+            null: 5,
+        };
+        console.log(
+            obj[void 0],
+            obj[undefined],
+            obj["undefined"],
+            obj[0/0],
+            obj[NaN],
+            obj["NaN"],
+            obj[1/0],
+            obj[Infinity],
+            obj["Infinity"],
+            obj[-1/0],
+            obj[-Infinity],
+            obj["-Infinity"],
+            obj[null],
+            obj["null"]
+        );
+    }
+    expect: {
+        var obj = {
+            undefined: 1,
+            NaN: 2,
+            Infinity: 3,
+            "-Infinity": 4,
+            null: 5,
+        };
+        console.log(
+            obj[void 0],
+            obj[void 0],
+            obj["undefined"],
+            obj[0/0],
+            obj[NaN],
+            obj["NaN"],
+            obj[1/0],
+            obj[1/0],
+            obj["Infinity"],
+            obj[-1/0],
+            obj[-1/0],
+            obj["-Infinity"],
+            obj[null],
+            obj["null"]
+        );
+    }
+    expect_stdout: "1 1 1 2 2 2 3 3 3 4 4 4 5 5"
+}
+
+numeric_literal: {
+    beautify = {
+        beautify: true,
+    }
+    mangle_props = {}
+    input: {
+        var obj = {
+            0: 0,
+            "-0": 1,
+            42: 2,
+            "42": 3,
+            0x25: 4,
+            "0x25": 5,
+            1E42: 6,
+            "1E42": 7,
+            "1e+42": 8,
+        };
+        console.log(obj[-0], obj[-""], obj["-0"]);
+        console.log(obj[42], obj["42"]);
+        console.log(obj[0x25], obj["0x25"], obj[37], obj["37"]);
+        console.log(obj[1E42], obj["1E42"], obj["1e+42"]);
+    }
+    expect_exact: [
+        'var obj = {',
+        '    0: 0,',
+        '    "-0": 1,',
+        '    42: 2,',
+        '    "42": 3,',
+        '    37: 4,',
+        '    a: 5,',
+        '    1e42: 6,',
+        '    b: 7,',
+        '    "1e+42": 8',
+        '};',
+        '',
+        'console.log(obj[-0], obj[-""], obj["-0"]);',
+        '',
+        'console.log(obj[42], obj["42"]);',
+        '',
+        'console.log(obj[37], obj["a"], obj[37], obj["37"]);',
+        '',
+        'console.log(obj[1e42], obj["b"], obj["1e+42"]);',
+    ]
+    expect_stdout: [
+        "0 0 1",
+        "3 3",
+        "4 5 4 4",
+        "8 7 8",
+    ]
+}
+
+identifier: {
+    mangle_props = {}
+    input: {
+        var obj = {
+            abstract: 1,
+            boolean: 2,
+            byte: 3,
+            char: 4,
+            class: 5,
+            double: 6,
+            enum: 7,
+            export: 8,
+            extends: 9,
+            final: 10,
+            float: 11,
+            goto: 12,
+            implements: 13,
+            import: 14,
+            int: 15,
+            interface: 16,
+            let: 17,
+            long: 18,
+            native: 19,
+            package: 20,
+            private: 21,
+            protected: 22,
+            public: 23,
+            short: 24,
+            static: 25,
+            super: 26,
+            synchronized: 27,
+            this: 28,
+            throws: 29,
+            transient: 30,
+            volatile: 31,
+            yield: 32,
+            false: 33,
+            null: 34,
+            true: 35,
+            break: 36,
+            case: 37,
+            catch: 38,
+            const: 39,
+            continue: 40,
+            debugger: 41,
+            default: 42,
+            delete: 43,
+            do: 44,
+            else: 45,
+            finally: 46,
+            for: 47,
+            function: 48,
+            if: 49,
+            in: 50,
+            instanceof: 51,
+            new: 52,
+            return: 53,
+            switch: 54,
+            throw: 55,
+            try: 56,
+            typeof: 57,
+            var: 58,
+            void: 59,
+            while: 60,
+            with: 61,
+        };
+    }
+    expect: {
+        var obj = {
+            a: 1,
+            b: 2,
+            c: 3,
+            d: 4,
+            e: 5,
+            f: 6,
+            g: 7,
+            h: 8,
+            i: 9,
+            j: 10,
+            k: 11,
+            l: 12,
+            m: 13,
+            n: 14,
+            o: 15,
+            p: 16,
+            q: 17,
+            r: 18,
+            s: 19,
+            t: 20,
+            u: 21,
+            v: 22,
+            w: 23,
+            x: 24,
+            y: 25,
+            z: 26,
+            A: 27,
+            B: 28,
+            C: 29,
+            D: 30,
+            F: 31,
+            G: 32,
+            false: 33,
+            null: 34,
+            true: 35,
+            H: 36,
+            I: 37,
+            J: 38,
+            K: 39,
+            L: 40,
+            M: 41,
+            N: 42,
+            O: 43,
+            P: 44,
+            Q: 45,
+            R: 46,
+            S: 47,
+            T: 48,
+            U: 49,
+            V: 50,
+            W: 51,
+            X: 52,
+            Y: 53,
+            Z: 54,
+            $: 55,
+            _: 56,
+            aa: 57,
+            ba: 58,
+            ca: 59,
+            da: 60,
+            ea: 61,
+        };
+    }
+}

test/compress/issue-1787.js

@@ -0,0 +1,19 @@
+unary_prefix: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            var x = -(2 / 3);
+            return x;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            return -2 / 3;
+        }());
+    }
+    expect_stdout: true
+}

test/compress/issue-1833.js

@@ -0,0 +1,134 @@
+iife_for: {
+    options = {
+        negate_iife: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                L: for (;;) break L;
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        !function() {
+            !function() {
+                L: for (;;) break L;
+            }();
+        }();
+    }
+}
+
+iife_for_in: {
+    options = {
+        negate_iife: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                L: for (var a in x) break L;
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        !function() {
+            !function() {
+                L: for (var a in x) break L;
+            }();
+        }();
+    }
+}
+
+iife_do: {
+    options = {
+        negate_iife: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                L: do {
+                    break L;
+                } while (1);
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        !function() {
+            !function() {
+                L: do {
+                    break L;
+                } while (1);
+            }();
+        }();
+    }
+}
+
+iife_while: {
+    options = {
+        negate_iife: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                L: while (1) break L;
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        !function() {
+            !function() {
+                L: while (1) break L;
+            }();
+        }();
+    }
+}
+
+label_do: {
+    options = {
+        evaluate: true,
+        loops: true,
+    }
+    input: {
+        L: do {
+            continue L;
+        } while (0);
+    }
+    expect: {
+        L: do {
+            continue L;
+        } while (0);
+    }
+}
+
+label_while: {
+    options = {
+        evaluate: true,
+        dead_code: true,
+        loops: true,
+    }
+    input: {
+        function f() {
+            L: while (0) continue L;
+        }
+    }
+    expect_exact: "function f(){L:;}"
+}

test/compress/issue-208.js

@@ -1,11 +1,70 @@
 do_not_update_lhs: {
-    options = { global_defs: { DEBUG: false } };
-    input: { DEBUG = false; }
-    expect: { DEBUG = false; }
+    options = {
+        global_defs: { DEBUG: 0 }
+    }
+    input: {
+        DEBUG++;
+        DEBUG += 1;
+        DEBUG = 1;
+    }
+    expect: {
+        DEBUG++;
+        DEBUG += 1;
+        DEBUG = 1;
+    }
 }
 
 do_update_rhs: {
-    options = { global_defs: { DEBUG: false } };
-    input: { MY_DEBUG = DEBUG; }
-    expect: { MY_DEBUG = false; }
+    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-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

@@ -6,7 +6,7 @@ NaN_and_Infinity_must_have_parens: {
     }
     expect: {
         (1/0).toString();
-        NaN.toString();         // transformation to 0/0 dropped
+        NaN.toString();
     }
 }
 
@@ -23,3 +23,135 @@ NaN_and_Infinity_should_not_be_replaced_when_they_are_redefined: {
         NaN.toString();
     }
 }
+
+NaN_and_Infinity_must_have_parens_evaluate: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        (123456789 / 0).toString();
+        (+"foo").toString();
+    }
+    expect: {
+        (1/0).toString();
+        NaN.toString();
+    }
+}
+
+NaN_and_Infinity_should_not_be_replaced_when_they_are_redefined_evaluate: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        var Infinity, NaN;
+        (123456789 / 0).toString();
+        (+"foo").toString();
+    }
+    expect: {
+        var Infinity, NaN;
+        (1/0).toString();
+        (0/0).toString();
+    }
+}
+
+beautify_off_1: {
+    options = {
+        evaluate: true,
+    }
+    beautify = {
+        beautify: false,
+    }
+    input: {
+        var NaN;
+        console.log(
+            null,
+            undefined,
+            Infinity,
+            NaN,
+            Infinity * undefined,
+            Infinity.toString(),
+            NaN.toString(),
+            (Infinity * undefined).toString()
+        );
+    }
+    expect_exact: "var NaN;console.log(null,void 0,1/0,NaN,0/0,(1/0).toString(),NaN.toString(),(0/0).toString());"
+    expect_stdout: true
+}
+
+beautify_off_2: {
+    options = {
+        evaluate: true,
+    }
+    beautify = {
+        beautify: false,
+    }
+    input: {
+        console.log(
+            null.toString(),
+            undefined.toString()
+        );
+    }
+    expect_exact: "console.log(null.toString(),(void 0).toString());"
+}
+
+beautify_on_1: {
+    options = {
+        evaluate: true,
+    }
+    beautify = {
+        beautify: true,
+    }
+    input: {
+        var NaN;
+        console.log(
+            null,
+            undefined,
+            Infinity,
+            NaN,
+            Infinity * undefined,
+            Infinity.toString(),
+            NaN.toString(),
+            (Infinity * undefined).toString()
+        );
+    }
+    expect_exact: [
+        "var NaN;",
+        "",
+        "console.log(null, void 0, 1 / 0, NaN, 0 / 0, (1 / 0).toString(), NaN.toString(), (0 / 0).toString());",
+    ]
+    expect_stdout: true
+}
+
+beautify_on_2: {
+    options = {
+        evaluate: true,
+    }
+    beautify = {
+        beautify: true,
+    }
+    input: {
+        console.log(
+            null.toString(),
+            undefined.toString()
+        );
+    }
+    expect_exact: "console.log(null.toString(), (void 0).toString());"
+}
+
+issue_1724: {
+    input: {
+        var a = 0;
+        ++a % Infinity | Infinity ? a++ : 0;
+        console.log(a);
+    }
+    expect_exact: "var a=0;++a%(1/0)|1/0?a++:0;console.log(a);"
+    expect_stdout: "2"
+}
+
+issue_1725: {
+    input: {
+        ([].length === 0) % Infinity ? console.log("PASS") : console.log("FAIL");
+    }
+    expect_exact: '(0===[].length)%(1/0)?console.log("PASS"):console.log("FAIL");'
+    expect_stdout: "PASS"
+}

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-892.js

@@ -29,4 +29,5 @@ dont_mangle_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-973.js

@@ -50,6 +50,7 @@ this_binding_conditionals: {
 this_binding_collapse_vars: {
     options = {
         collapse_vars: true,
+        toplevel: true,
     };
     input: {
         var c = a; c();

test/compress/issue-976.js

@@ -42,6 +42,7 @@ eval_collapse_vars: {
             eval("console.log(a);");
         })(eval);
     }
+    expect_stdout: true
 }
 
 eval_unused: {

test/compress/issue-979.js

@@ -82,7 +82,7 @@ issue979_test_negated_is_best: {
             1!=a||2!=b||foo();
         }
         function f7() {
-            return 1!=a&&2!=b?bar():void foo();
+            if(1!=a&&2!=b)return bar();foo()
         }
     }
 }

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

@@ -145,3 +145,338 @@ parse_do_while_without_semicolon: {
         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();
+        d();
+    }
+}
+
+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();',
+        '}',
+    ]
+}
+
+issue_1648: {
+    options = {
+        join_vars: true,
+        loops: true,
+        passes: 2,
+        sequences: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            x();
+            var b = 1;
+            while (1);
+        }
+    }
+    expect_exact: "function f(){for(x();1;);}"
+}
+
+do_switch: {
+    options = {
+        evaluate: true,
+        loops: true,
+    }
+    input: {
+        do {
+            switch (a) {
+              case b:
+                continue;
+            }
+        } while (false);
+    }
+    expect: {
+        do {
+            switch (a) {
+              case b:
+                continue;
+            }
+        } while (false);
+    }
+}

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

@@ -10,6 +10,16 @@ negate_iife_1: {
     }
 }
 
+negate_iife_1_off: {
+    options = {
+        negate_iife: false,
+    };
+    input: {
+        (function(){ stuff() })();
+    }
+    expect_exact: '(function(){stuff()})();'
+}
+
 negate_iife_2: {
     options = {
         negate_iife: true
@@ -22,44 +32,151 @@ negate_iife_2: {
     }
 }
 
-negate_iife_3: {
+negate_iife_2_side_effects: {
     options = {
         negate_iife: true,
-    };
+        side_effects: true,
+    }
     input: {
-        (function(){ return true })() ? console.log(true) : console.log(false);
+        (function(){ return {} })().x = 10; // should not transform this one
     }
     expect: {
-        !function(){ return true }() ? console.log(false) : console.log(true);
+        (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 true })() ? console.log(true) : console.log(false);
+        (function(){ return t })() ? console.log(true) : console.log(false);
         (function(){
             console.log("something");
         })();
     }
     expect: {
-        !function(){ return true }() ? console.log(false) : console.log(true), function(){
+        !function(){ return t }() ? console.log(false) : console.log(true), function(){
             console.log("something");
         }();
     }
 }
 
-negate_iife_4: {
+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 true })()) {
+        if ((function(){ return t })()) {
             foo(true);
         } else {
             bar(false);
@@ -69,7 +186,30 @@ negate_iife_4: {
         })();
     }
     expect: {
-        !function(){ return true }() ? bar(false) : foo(true), function(){
+        !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");
         }();
     }
@@ -105,6 +245,40 @@ negate_iife_nested: {
             }(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: {
@@ -129,4 +303,116 @@ negate_iife_issue_1073: {
             };
         }(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 = {
+        conditionals: true,
+        negate_iife: true,
+        side_effects: false,
+    };
+    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

@@ -50,3 +50,35 @@ new_with_many_parameters: {
     }
     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);';
+}

test/compress/numbers.js

@@ -17,3 +17,188 @@ hex_numbers_in_parentheses_for_prototype_functions: {
     }
     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
+        );
+    }
+}
+
+issue_1710: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        var x = {};
+        console.log((x += 1) + -x);
+    }
+    expect: {
+        var x = {};
+        console.log((x += 1) + -x);
+    }
+    expect_stdout: true
+}
+
+unary_binary_parenthesis: {
+    input: {
+        var v = [ 0, 1, NaN, Infinity, null, undefined, true, false, "", "foo", /foo/ ];
+        v.forEach(function(x) {
+            v.forEach(function(y) {
+                console.log(
+                    +(x*y),
+                    +(x/y),
+                    +(x%y),
+                    -(x*y),
+                    -(x/y),
+                    -(x%y)
+                );
+            });
+        });
+    }
+    expect: {
+        var v = [ 0, 1, NaN, 1/0, null, void 0, true, false, "", "foo", /foo/ ];
+        v.forEach(function(x) {
+            v.forEach(function(y) {
+                console.log(
+                    +x*y,
+                    +x/y,
+                    +x%y,
+                    -x*y,
+                    -x/y,
+                    -x%y
+                );
+            });
+        });
+    }
+    expect_stdout: true
+}

test/compress/properties.js

@@ -54,7 +54,56 @@ dot_properties_es5: {
     }
 }
 
-evaluate_length: {
+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,
@@ -82,15 +131,22 @@ mangle_properties: {
         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
     }
@@ -100,27 +156,402 @@ mangle_unquoted_properties: {
         keep_quoted_props: true,
     }
     input: {
+        a.top = 1;
         function f1() {
             a["foo"] = "bar";
             a.color = "red";
-            x = {"bar": 10};
+            a.stuff = 2;
+            x = {"bar": 10, size: 7};
+            a.size = 9;
         }
         function f2() {
             a.foo = "bar";
             a['color'] = "red";
-            x = {bar: 10};
+            x = {bar: 10, size: 7};
+            a.size = 9;
+            a.stuff = 3;
         }
     }
     expect: {
+        a.a = 1;
         function f1() {
             a["foo"] = "bar";
-            a.a = "red";
-            x = {"bar": 10};
+            a.color = "red";
+            a.b = 2;
+            x = {"bar": 10, c: 7};
+            a.c = 9;
         }
         function f2() {
-            a.b = "bar";
+            a.foo = "bar";
             a['color'] = "red";
-            x = {c: 10};
+            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();
+    }
+}

test/compress/pure_getters.js

@@ -0,0 +1,121 @@
+strict: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: false,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var a, b = null, c = {};
+        a.prop;
+        b.prop;
+        c.prop;
+        d.prop;
+        null.prop;
+        (void 0).prop;
+        undefined.prop;
+    }
+    expect: {
+        var a, b = null, c = {};
+        a.prop;
+        b.prop;
+        c.prop;
+        d.prop;
+        null.prop;
+        (void 0).prop;
+        (void 0).prop;
+    }
+}
+
+strict_reduce_vars: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var a, b = null, c = {};
+        a.prop;
+        b.prop;
+        c.prop;
+        d.prop;
+        null.prop;
+        (void 0).prop;
+        undefined.prop;
+    }
+    expect: {
+        var a, b = null, c = {};
+        a.prop;
+        b.prop;
+        d.prop;
+        null.prop;
+        (void 0).prop;
+        (void 0).prop;
+    }
+}
+
+unsafe: {
+    options = {
+        pure_getters: true,
+        reduce_vars: false,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var a, b = null, c = {};
+        a.prop;
+        b.prop;
+        c.prop;
+        d.prop;
+        null.prop;
+        (void 0).prop;
+        undefined.prop;
+    }
+    expect: {
+        var a, b = null, c = {};
+        d;
+        null.prop;
+        (void 0).prop;
+        (void 0).prop;
+    }
+}
+
+unsafe_reduce_vars: {
+    options = {
+        pure_getters: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var a, b = null, c = {};
+        a.prop;
+        b.prop;
+        c.prop;
+        d.prop;
+        null.prop;
+        (void 0).prop;
+        undefined.prop;
+    }
+    expect: {
+        var a, b = null, c = {};
+        d;
+        null.prop;
+        (void 0).prop;
+        (void 0).prop;
+    }
+}
+
+chained: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+    }
+    input: {
+        a.b.c;
+    }
+    expect: {
+        a.b.c;
+    }
+}

test/compress/screw-ie8.js

@@ -1,18 +1,233 @@
 do_screw: {
-    options = { screw_ie8: true };
+    options = {
+        screw_ie8: true,
+    }
     beautify = {
         screw_ie8: true,
-        ascii_only: true
-    };
-
-    input: f("\v");
-    expect_exact: 'f("\\v");';
+        ascii_only: true,
+    }
+    input: {
+        f("\v");
+    }
+    expect_exact: 'f("\\v");'
 }
 
 dont_screw: {
-    options = { screw_ie8: false };
-    beautify = { screw_ie8: false, ascii_only: true };
-
-    input: f("\v");
-    expect_exact: 'f("\\x0B");';
+    options = {
+        screw_ie8: false,
+    }
+    beautify = {
+        screw_ie8: false,
+        ascii_only: true,
+    }
+    input: {
+        f("\v");
+    }
+    expect_exact: 'f("\\x0B");'
+}
+
+do_screw_constants: {
+    options = {
+        screw_ie8: true,
+    }
+    input: {
+        f(undefined, Infinity);
+    }
+    expect_exact: "f(void 0,1/0);"
+}
+
+dont_screw_constants: {
+    options = {
+        screw_ie8: false,
+    }
+    input: {
+        f(undefined, Infinity);
+    }
+    expect_exact: "f(undefined,Infinity);"
+}
+
+do_screw_try_catch: {
+    options = { screw_ie8: true };
+    mangle = { screw_ie8: true };
+    beautify = { screw_ie8: true };
+    input: {
+        good = function(e){
+            return function(error){
+                try{
+                    e()
+                } catch(e) {
+                    error(e)
+                }
+            }
+        };
+    }
+    expect: {
+        good = function(n){
+            return function(t){
+                try{
+                    n()
+                } catch(n) {
+                    t(n)
+                }
+            }
+        };
+    }
+}
+
+dont_screw_try_catch: {
+    options = { screw_ie8: false };
+    mangle = { screw_ie8: false };
+    beautify = { screw_ie8: false };
+    input: {
+        bad = function(e){
+            return function(error){
+                try{
+                    e()
+                } catch(e) {
+                    error(e)
+                }
+            }
+        };
+    }
+    expect: {
+        bad = function(n){
+            return function(t){
+                try{
+                    n()
+                } catch(n) {
+                    t(n)
+                }
+            }
+        };
+    }
+}
+
+do_screw_try_catch_undefined: {
+    options = { screw_ie8: true };
+    mangle = { screw_ie8: true };
+    beautify = { screw_ie8: true };
+    input: {
+        function a(b){
+            try {
+                throw 'Stuff';
+            } catch (undefined) {
+                console.log('caught: ' + undefined);
+            }
+            console.log('undefined is ' + undefined);
+            return b === undefined;
+        };
+    }
+    expect: {
+        function a(o){
+            try{
+                throw "Stuff"
+            } catch (o) {
+                console.log("caught: "+o)
+            }
+            console.log("undefined is " + void 0);
+            return void 0===o
+        }
+    }
+    expect_stdout: true
+}
+
+dont_screw_try_catch_undefined: {
+    options = { screw_ie8: false };
+    mangle = { screw_ie8: false };
+    beautify = { screw_ie8: false };
+    input: {
+        function a(b){
+            try {
+                throw 'Stuff';
+            } catch (undefined) {
+                console.log('caught: ' + undefined);
+            }
+            console.log('undefined is ' + undefined);
+            return b === undefined;
+        };
+    }
+    expect: {
+        function a(n){
+            try{
+                throw "Stuff"
+            } catch (undefined) {
+                console.log("caught: " + undefined)
+            }
+            console.log("undefined is " + undefined);
+            return n === undefined
+        }
+    }
+    expect_stdout: true
+}
+
+reduce_vars: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        screw_ie8: false,
+        unused: true,
+    }
+    mangle = {
+        screw_ie8: false,
+    }
+    input: {
+        function f() {
+            var a;
+            try {
+                x();
+            } catch (a) {
+                y();
+            }
+            alert(a);
+        }
+    }
+    expect: {
+        function f() {
+            var t;
+            try {
+                x();
+            } catch (t) {
+                y();
+            }
+            alert(t);
+        }
+    }
+}
+
+issue_1586_1: {
+    options = {
+        screw_ie8: false,
+    }
+    mangle = {
+        screw_ie8: false,
+    }
+    input: {
+        function f() {
+            try {
+                x();
+            } catch (err) {
+                console.log(err.message);
+            }
+        }
+    }
+    expect_exact: "function f(){try{x()}catch(c){console.log(c.message)}}"
+}
+
+issue_1586_2: {
+    options = {
+        screw_ie8: true,
+    }
+    mangle = {
+        screw_ie8: true,
+    }
+    input: {
+        function f() {
+            try {
+                x();
+            } catch (err) {
+                console.log(err.message);
+            }
+        }
+    }
+    expect_exact: "function f(){try{x()}catch(c){console.log(c.message)}}"
 }

test/compress/sequences.js

@@ -86,6 +86,7 @@ make_sequences_4: {
         switch (x = 5, y) {}
         with (x = 5, obj);
     }
+    expect_stdout: true
 }
 
 lift_sequences_1: {
@@ -103,15 +104,18 @@ lift_sequences_1: {
 lift_sequences_2: {
     options = { sequences: true, evaluate: true };
     input: {
-        var foo, bar;
+        var foo = 1, bar;
         foo.x = (foo = {}, 10);
         bar = (bar = {}, 10);
+        console.log(foo, bar);
     }
     expect: {
-        var foo, bar;
+        var foo = 1, bar;
         foo.x = (foo = {}, 10),
-        bar = {}, bar = 10;
+        bar = {}, bar = 10,
+        console.log(foo, bar);
     }
+    expect_stdout: true
 }
 
 lift_sequences_3: {
@@ -138,6 +142,23 @@ lift_sequences_4: {
     }
 }
 
+lift_sequences_5: {
+    options = {
+        sequences: true,
+    }
+    input: {
+        var a = 2, b;
+        a *= (b, a = 4, 3);
+        console.log(a);
+    }
+    expect: {
+        var a = 2, b;
+        b, a *= (a = 4, 3),
+        console.log(a);
+    }
+    expect_stdout: "6"
+}
+
 for_sequences: {
     options = { sequences: true };
     input: {
@@ -169,3 +190,423 @@ for_sequences: {
         for (y = 5; false;);
     }
 }
+
+limit_1: {
+    options = {
+        sequences: 3,
+    };
+    input: {
+        a;
+        b;
+        c;
+        d;
+        e;
+        f;
+        g;
+        h;
+        i;
+        j;
+        k;
+    }
+    expect: {
+        a, b, c;
+        d, e, f;
+        g, h, i;
+        j, k;
+    }
+}
+
+limit_2: {
+    options = {
+        sequences: 3,
+    };
+    input: {
+        a, b;
+        c, d;
+        e, f;
+        g, h;
+        i, j;
+        k;
+    }
+    expect: {
+        a, b, c, d;
+        e, f, g, h;
+        i, j, k;
+    }
+}
+
+negate_iife_for: {
+    options = {
+        sequences: true,
+        negate_iife: true,
+    };
+    input: {
+        (function() {})();
+        for (i = 0; i < 5; i++) console.log(i);
+
+        (function() {})();
+        for (; i < 5; i++) console.log(i);
+    }
+    expect: {
+        for (!function() {}(), i = 0; i < 5; i++) console.log(i);
+        for (function() {}(); i < 5; i++) console.log(i);
+    }
+    expect_stdout: true
+}
+
+iife: {
+    options = {
+        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() {}(), function g() {}();
+    }
+}
+
+unsafe_undefined: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        sequences: true,
+        side_effects: true,
+        unsafe: true,
+    }
+    input: {
+        function f(undefined) {
+            if (a)
+                return b;
+            if (c)
+                return d;
+        }
+        function g(undefined) {
+            if (a)
+                return b;
+            if (c)
+                return d;
+            e();
+        }
+    }
+    expect: {
+        function f(undefined) {
+            return a ? b : c ? d : undefined;
+        }
+        function g(undefined) {
+            return a ? b : c ? d : void e();
+        }
+    }
+}
+
+issue_1685: {
+    options = {
+        cascade: true,
+        side_effects: true,
+    }
+    input: {
+        var a = 100, b = 10;
+        function f() {
+            var a = (a--, delete a && --b);
+        }
+        f();
+        console.log(a, b);
+    }
+    expect: {
+        var a = 100, b = 10;
+        function f() {
+            var a = (a--, delete a && --b);
+        }
+        f();
+        console.log(a, b);
+    }
+    expect_stdout: true
+}
+
+func_def_1: {
+    options = {
+        cascade: true,
+        side_effects: true,
+    }
+    input: {
+        function f() {
+            return f = 0, !!f;
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            return !!(f = 0);
+        }
+        console.log(f());
+    }
+    expect_stdout: "false"
+}
+
+func_def_2: {
+    options = {
+        cascade: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(function f() {
+            return f = 0, !!f;
+        }());
+    }
+    expect: {
+        console.log(function f() {
+            return f = 0, !!f;
+        }());
+    }
+    expect_stdout: "true"
+}
+
+func_def_3: {
+    options = {
+        cascade: true,
+        side_effects: true,
+    }
+    input: {
+        function f() {
+            function g() {}
+            return g = 0, !!g;
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            function g() {}
+            return !!(g = 0);
+        }
+        console.log(f());
+    }
+    expect_stdout: "false"
+}
+
+func_def_4: {
+    options = {
+        cascade: true,
+        side_effects: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                return g = 0, !!g;
+            }
+            return g();
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            function g() {
+                return !!(g = 0);
+            }
+            return g();
+        }
+        console.log(f());
+    }
+    expect_stdout: "false"
+}
+
+func_def_5: {
+    options = {
+        cascade: true,
+        side_effects: true,
+    }
+    input: {
+        function f() {
+            return function g(){
+                return g = 0, !!g;
+            }();
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            return function g(){
+                return g = 0, !!g;
+            }();
+        }
+        console.log(f());
+    }
+    expect_stdout: "true"
+}
+
+issue_1758: {
+    options = {
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(function(c) {
+            var undefined = 42;
+            return function() {
+                c--;
+                c--, c.toString();
+                return;
+            }();
+        }());
+    }
+    expect: {
+        console.log(function(c) {
+            var undefined = 42;
+            return function() {
+                return c--, c--, c.toString(), void 0;
+            }();
+        }());
+    }
+    expect_stdout: "undefined"
+}
+
+delete_seq_1: {
+    options = {
+        booleans: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(delete (1, undefined));
+        console.log(delete (1, void 0));
+        console.log(delete (1, Infinity));
+        console.log(delete (1, 1 / 0));
+        console.log(delete (1, NaN));
+        console.log(delete (1, 0 / 0));
+    }
+    expect: {
+        console.log((void 0, !0));
+        console.log((void 0, !0));
+        console.log((1 / 0, !0));
+        console.log((1 / 0, !0));
+        console.log((NaN, !0));
+        console.log((0 / 0, !0));
+    }
+    expect_stdout: true
+}
+
+delete_seq_2: {
+    options = {
+        booleans: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(delete (1, 2, undefined));
+        console.log(delete (1, 2, void 0));
+        console.log(delete (1, 2, Infinity));
+        console.log(delete (1, 2, 1 / 0));
+        console.log(delete (1, 2, NaN));
+        console.log(delete (1, 2, 0 / 0));
+    }
+    expect: {
+        console.log((void 0, !0));
+        console.log((void 0, !0));
+        console.log((1 / 0, !0));
+        console.log((1 / 0, !0));
+        console.log((NaN, !0));
+        console.log((0 / 0, !0));
+    }
+    expect_stdout: true
+}
+
+delete_seq_3: {
+    options = {
+        booleans: true,
+        keep_infinity: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(delete (1, 2, undefined));
+        console.log(delete (1, 2, void 0));
+        console.log(delete (1, 2, Infinity));
+        console.log(delete (1, 2, 1 / 0));
+        console.log(delete (1, 2, NaN));
+        console.log(delete (1, 2, 0 / 0));
+    }
+    expect: {
+        console.log((void 0, !0));
+        console.log((void 0, !0));
+        console.log((Infinity, !0));
+        console.log((1 / 0, !0));
+        console.log((NaN, !0));
+        console.log((0 / 0, !0));
+    }
+    expect_stdout: true
+}
+
+delete_seq_4: {
+    options = {
+        booleans: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        function f() {}
+        console.log(delete (f(), undefined));
+        console.log(delete (f(), void 0));
+        console.log(delete (f(), Infinity));
+        console.log(delete (f(), 1 / 0));
+        console.log(delete (f(), NaN));
+        console.log(delete (f(), 0 / 0));
+    }
+    expect: {
+        function f() {}
+        console.log((f(), !0)),
+        console.log((f(), !0)),
+        console.log((f(), !0)),
+        console.log((f(), !0)),
+        console.log((f(), !0)),
+        console.log((f(), !0));
+    }
+    expect_stdout: true
+}
+
+delete_seq_5: {
+    options = {
+        booleans: true,
+        keep_infinity: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        function f() {}
+        console.log(delete (f(), undefined));
+        console.log(delete (f(), void 0));
+        console.log(delete (f(), Infinity));
+        console.log(delete (f(), 1 / 0));
+        console.log(delete (f(), NaN));
+        console.log(delete (f(), 0 / 0));
+    }
+    expect: {
+        function f() {}
+        console.log((f(), !0)),
+        console.log((f(), !0)),
+        console.log((f(), !0)),
+        console.log((f(), !0)),
+        console.log((f(), !0)),
+        console.log((f(), !0));
+    }
+    expect_stdout: true
+}
+
+delete_seq_6: {
+    options = {
+        booleans: true,
+        side_effects: true,
+    }
+    input: {
+        var a;
+        console.log(delete (1, a));
+    }
+    expect: {
+        var a;
+        console.log((a, !0));
+    }
+    expect_stdout: true
+}

test/compress/switch.js

@@ -1,5 +1,10 @@
 constant_switch_1: {
-    options = { dead_code: true, evaluate: true };
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
     input: {
         switch (1+1) {
           case 1: foo(); break;
@@ -13,7 +18,12 @@ constant_switch_1: {
 }
 
 constant_switch_2: {
-    options = { dead_code: true, evaluate: true };
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
     input: {
         switch (1) {
           case 1: foo();
@@ -28,7 +38,12 @@ constant_switch_2: {
 }
 
 constant_switch_3: {
-    options = { dead_code: true, evaluate: true };
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
     input: {
         switch (10) {
           case 1: foo();
@@ -44,7 +59,12 @@ constant_switch_3: {
 }
 
 constant_switch_4: {
-    options = { dead_code: true, evaluate: true };
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
     input: {
         switch (2) {
           case 1:
@@ -65,7 +85,12 @@ constant_switch_4: {
 }
 
 constant_switch_5: {
-    options = { dead_code: true, evaluate: true };
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
     input: {
         switch (1) {
           case 1:
@@ -94,7 +119,12 @@ constant_switch_5: {
 }
 
 constant_switch_6: {
-    options = { dead_code: true, evaluate: true };
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
     input: {
         OUT: {
             foo();
@@ -123,7 +153,12 @@ constant_switch_6: {
 }
 
 constant_switch_7: {
-    options = { dead_code: true, evaluate: true };
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
     input: {
         OUT: {
             foo();
@@ -161,7 +196,12 @@ constant_switch_7: {
 }
 
 constant_switch_8: {
-    options = { dead_code: true, evaluate: true };
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
     input: {
         OUT: switch (1) {
           case 1:
@@ -185,7 +225,12 @@ constant_switch_8: {
 }
 
 constant_switch_9: {
-    options = { dead_code: true, evaluate: true };
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
     input: {
         OUT: switch (1) {
           case 1:
@@ -210,7 +255,10 @@ constant_switch_9: {
 }
 
 drop_default_1: {
-    options = { dead_code: true };
+    options = {
+        dead_code: true,
+        switches: true,
+    }
     input: {
         switch (foo) {
           case 'bar': baz();
@@ -225,7 +273,10 @@ drop_default_1: {
 }
 
 drop_default_2: {
-    options = { dead_code: true };
+    options = {
+        dead_code: true,
+        switches: true,
+    }
     input: {
         switch (foo) {
           case 'bar': baz(); break;
@@ -241,7 +292,10 @@ drop_default_2: {
 }
 
 keep_default: {
-    options = { dead_code: true };
+    options = {
+        dead_code: true,
+        switches: true,
+    }
     input: {
         switch (foo) {
           case 'bar': baz();
@@ -258,3 +312,507 @@ keep_default: {
         }
     }
 }
+
+issue_1663: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
+    input: {
+        var a = 100, b = 10;
+        function f() {
+            switch (1) {
+              case 1:
+                b = a++;
+                return ++b;
+              default:
+                var b;
+            }
+        }
+        f();
+        console.log(a, b);
+    }
+    expect: {
+        var a = 100, b = 10;
+        function f() {
+            var b;
+            b = a++;
+            return ++b;
+        }
+        f();
+        console.log(a, b);
+    }
+    expect_stdout: true
+}
+
+drop_case: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        switch (foo) {
+          case 'bar': baz(); break;
+          case 'moo':
+            break;
+        }
+    }
+    expect: {
+        switch (foo) {
+          case 'bar': baz();
+        }
+    }
+}
+
+keep_case: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        switch (foo) {
+          case 'bar': baz(); break;
+          case moo:
+            break;
+        }
+    }
+    expect: {
+        switch (foo) {
+          case 'bar': baz(); break;
+          case moo:
+        }
+    }
+}
+
+issue_376: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        switches: true,
+    }
+    input: {
+        switch (true) {
+          case boolCondition:
+            console.log(1);
+            break;
+          case false:
+            console.log(2);
+            break;
+        }
+    }
+    expect: {
+        switch (true) {
+          case boolCondition:
+            console.log(1);
+        }
+    }
+}
+
+issue_441_1: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        switch (foo) {
+          case bar:
+            qux();
+            break;
+          case baz:
+            qux();
+            break;
+          default:
+            qux();
+            break;
+        }
+    }
+    expect: {
+        switch (foo) {
+          case bar:
+          case baz:
+          default:
+            qux();
+        }
+    }
+}
+
+issue_441_2: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        switch (foo) {
+          case bar:
+            // TODO: Fold into the case below
+            qux();
+            break;
+          case fall:
+          case baz:
+            qux();
+            break;
+          default:
+            qux();
+            break;
+        }
+    }
+    expect: {
+        switch (foo) {
+          case bar:
+            qux();
+            break;
+          case fall:
+          case baz:
+          default:
+            qux();
+        }
+    }
+}
+
+issue_1674: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        side_effects: true,
+        switches: true,
+    }
+    input: {
+        switch (0) {
+          default:
+            console.log("FAIL");
+            break;
+          case 0:
+            console.log("PASS");
+            break;
+        }
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_1679: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        switches: true,
+    }
+    input: {
+        var a = 100, b = 10;
+        function f() {
+            switch (--b) {
+              default:
+              case !function x() {}:
+                break;
+              case b--:
+                switch (0) {
+                  default:
+                  case a--:
+                }
+                break;
+              case (a++):
+                break;
+            }
+        }
+        f();
+        console.log(a, b);
+    }
+    expect: {
+        var a = 100, b = 10;
+        function f() {
+            switch (--b) {
+              default:
+              case !function x() {}:
+                break;
+              case b--:
+                switch (0) {
+                  default:
+                  case a--:
+                }
+                break;
+              case (a++):
+            }
+        }
+        f();
+        console.log(a, b);
+    }
+    expect_stdout: true
+}
+
+issue_1680_1: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        switches: true,
+    }
+    input: {
+        function f(x) {
+            console.log(x);
+            return x + 1;
+        }
+        switch (2) {
+          case f(0):
+          case f(1):
+            f(2);
+          case 2:
+          case f(3):
+          case f(4):
+            f(5);
+        }
+    }
+    expect: {
+        function f(x) {
+            console.log(x);
+            return x + 1;
+        }
+        switch (2) {
+          case f(0):
+          case f(1):
+            f(2);
+          case 2:
+            f(5);
+        }
+    }
+    expect_stdout: [
+        "0",
+        "1",
+        "2",
+        "5",
+    ]
+}
+
+issue_1680_2: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        var a = 100, b = 10;
+        switch (b) {
+          case a--:
+            break;
+          case b:
+            var c;
+            break;
+          case a:
+            break;
+          case a--:
+            break;
+        }
+        console.log(a, b);
+    }
+    expect: {
+        var a = 100, b = 10;
+        switch (b) {
+          case a--:
+            break;
+          case b:
+            var c;
+            break;
+          case a:
+          case a--:
+        }
+        console.log(a, b);
+    }
+    expect_stdout: true
+}
+
+issue_1690_1: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        switch (console.log("PASS")) {}
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_1690_2: {
+    options = {
+        dead_code: false,
+        switches: true,
+    }
+    input: {
+        switch (console.log("PASS")) {}
+    }
+    expect: {
+        switch (console.log("PASS")) {}
+    }
+    expect_stdout: "PASS"
+}
+
+if_switch_typeof: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        side_effects: true,
+        switches: true,
+    }
+    input: {
+        if (a) switch(typeof b) {}
+    }
+    expect: {
+        a;
+    }
+}
+
+issue_1698: {
+    options = {
+        side_effects: true,
+        switches: true,
+    }
+    input: {
+        var a = 1;
+        !function() {
+            switch (a++) {}
+        }();
+        console.log(a);
+    }
+    expect: {
+        var a = 1;
+        !function() {
+            switch (a++) {}
+        }();
+        console.log(a);
+    }
+    expect_stdout: "2"
+}
+
+issue_1705_1: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        var a = 0;
+        switch (a) {
+          default:
+            console.log("FAIL");
+          case 0:
+            break;
+        }
+    }
+    expect: {
+        var a = 0;
+        switch (a) {
+          default:
+            console.log("FAIL");
+          case 0:
+        }
+    }
+    expect_stdout: true
+}
+
+issue_1705_2: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        switches: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        switch (a) {
+          default:
+            console.log("FAIL");
+          case 0:
+            break;
+        }
+    }
+    expect: {
+    }
+    expect_stdout: true
+}
+
+issue_1705_3: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        switch (a) {
+          case 0:
+            break;
+          default:
+            break;
+        }
+    }
+    expect: {
+        a;
+    }
+    expect_stdout: true
+}
+
+beautify: {
+    beautify = {
+        beautify: true,
+    }
+    input: {
+        switch (a) {
+          case 0:
+          case 1:
+            break;
+          case 2:
+          default:
+        }
+        switch (b) {
+          case 3:
+            foo();
+            bar();
+          default:
+            break;
+        }
+    }
+    expect_exact: [
+        "switch (a) {",
+        "  case 0:",
+        "  case 1:",
+        "    break;",
+        "",
+        "  case 2:",
+        "  default:",
+        "}",
+        "",
+        "switch (b) {",
+        "  case 3:",
+        "    foo();",
+        "    bar();",
+        "",
+        "  default:",
+        "    break;",
+        "}",
+    ]
+}
+
+issue_1758: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        var a = 1, b = 2;
+        switch (a--) {
+          default:
+            b++;
+        }
+        console.log(a, b);
+    }
+    expect: {
+        var a = 1, b = 2;
+        a--;
+        b++;
+        console.log(a, b);
+    }
+    expect_stdout: "0 3"
+}

test/compress/transform.js

@@ -0,0 +1,130 @@
+booleans_evaluate: {
+    options = {
+        booleans: true,
+        evaluate: true,
+    }
+    input: {
+        console.log(typeof void 0 != "undefined");
+        console.log(1 == 1, 1 === 1)
+        console.log(1 != 1, 1 !== 1)
+    }
+    expect: {
+        console.log(!1);
+        console.log(!0, !0);
+        console.log(!1, !1);
+    }
+    expect_stdout: true
+}
+
+booleans_global_defs: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        global_defs: {
+            A: true,
+        },
+    }
+    input: {
+        console.log(A == 1);
+    }
+    expect: {
+        console.log(!0);
+    }
+}
+
+condition_evaluate: {
+    options = {
+        booleans: true,
+        dead_code: false,
+        evaluate: true,
+        loops: false,
+    }
+    input: {
+        while (1 === 2);
+        for (; 1 == true;);
+        if (void 0 == null);
+    }
+    expect: {
+        while (!1);
+        for (; !0;);
+        if (!0);
+    }
+}
+
+if_else_empty: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        if ({} ? a : b); else {}
+    }
+    expect: {
+        !{} ? b : a;
+    }
+}
+
+label_if_break: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+    }
+    input: {
+        L: if (true) {
+            a;
+            break L;
+        }
+    }
+    expect: {
+        a;
+    }
+}
+
+while_if_break: {
+    options = {
+        conditionals: true,
+        loops: true,
+        sequences: true,
+    }
+    input: {
+        while (a) {
+            if (b) if(c) d;
+            if (e) break;
+        }
+    }
+    expect: {
+        for(; a && (b && c && d, !e););
+    }
+}
+
+if_return: {
+    options = {
+        booleans: true,
+        conditionals: true,
+        if_return: true,
+        sequences: true,
+    }
+    input: {
+        function f(w, x, y, z) {
+            if (x) return;
+            if (w) {
+                if (y) return;
+            } else if (z) return;
+            if (x == y) return true;
+
+            if (x) w();
+            if (y) z();
+            return true;
+        }
+    }
+    expect: {
+        function f(w, x, y, z) {
+            if (!x) {
+                if (w) {
+                    if (y) return;
+                } else if (z) return;
+                return x == y || (x && w(), y && z(), !0);
+            }
+        }
+    }
+}

test/compress/typeof.js

@@ -23,3 +23,40 @@ typeof_evaluation: {
         h='undefined';
     }
 }
+
+typeof_in_boolean_context: {
+    options = {
+        booleans     : true,
+        evaluate     : true,
+        conditionals : true,
+        side_effects : true,
+    };
+    input: {
+        function f1(x) { return typeof x ? "yes" : "no"; }
+        function f2() { return typeof g()? "Yes" : "No"; }
+        typeof 0 ? foo() : bar();
+        !typeof console.log(1);
+        var a = !typeof console.log(2);
+        if (typeof (1 + foo()));
+    }
+    expect: {
+        function f1(x) { return "yes"; }
+        function f2() { return g(), "Yes"; }
+        foo();
+        console.log(1);
+        var a = !(console.log(2), !0);
+        foo();
+    }
+}
+
+issue_1668: {
+    options = {
+        booleans: true,
+    }
+    input: {
+        if (typeof bar);
+    }
+    expect: {
+        if (!0);
+    }
+}

test/compress/wrap_iife.js

@@ -0,0 +1,48 @@
+wrap_iife: {
+    options = {
+        negate_iife: false,
+    }
+    beautify = {
+        wrap_iife: true,
+    }
+    input: {
+        (function() {
+            return function() {
+                console.log('test')
+            };
+        })()();
+    }
+    expect_exact: '(function(){return function(){console.log("test")}})()();'
+}
+
+wrap_iife_in_expression: {
+    options = {
+        negate_iife: false,
+    }
+    beautify = {
+        wrap_iife: true,
+    }
+    input: {
+        foo = (function () {
+            return bar();
+        })();
+    }
+    expect_exact: 'foo=(function(){return bar()})();'
+}
+
+wrap_iife_in_return_call: {
+    options = {
+        negate_iife: false,
+    }
+    beautify = {
+        wrap_iife: true,
+    }
+    input: {
+        (function() {
+            return (function() {
+                console.log('test')
+            })();
+        })()();
+    }
+    expect_exact: '(function(){return(function(){console.log("test")})()})()();'
+}

test/input/comments/filter.js

@@ -0,0 +1,3 @@
+// foo
+/*@preserve*/
+// bar

test/input/global_defs/nested.js

@@ -0,0 +1 @@
+console.log(C.V, C.D);

test/input/global_defs/simple.js

@@ -0,0 +1 @@
+console.log(D);

test/input/invalid/assign_1.js

@@ -0,0 +1 @@
+console.log(1 || 5--);

test/input/invalid/assign_2.js

@@ -0,0 +1 @@
+console.log(2 || (Math.random() /= 2));

test/input/invalid/assign_3.js

@@ -0,0 +1 @@
+console.log(3 || ++this);

test/input/invalid/eof.js

@@ -0,0 +1 @@
+foo, bar(

test/input/invalid/loop-no-body.js

@@ -0,0 +1 @@
+for (var i = 0; i < 1; i++) 

test/input/invalid/simple.js

@@ -0,0 +1 @@
+function f(a{}

test/input/invalid/tab.js

@@ -0,0 +1 @@
+		foo(	xyz, 0abc);

test/input/issue-1236/simple.js

@@ -0,0 +1,8 @@
+"use strict";
+
+var foo = function foo(x) {
+  return "foo " + x;
+};
+console.log(foo("bar"));
+
+//# sourceMappingURL=simple.js.map

test/input/issue-1236/simple.js.map

@@ -0,0 +1,8 @@
+{
+    "version": 3,
+    "sources": ["index.js"],
+    "names": [],
+    "mappings": ";;AAAA,IAAI,MAAM,SAAN,GAAM;AAAA,SAAK,SAAS,CAAd;AAAA,CAAV;AACA,QAAQ,GAAR,CAAY,IAAI,KAAJ,CAAZ",
+    "file": "simple.js",
+    "sourcesContent": ["let foo = x => \"foo \" + x;\nconsole.log(foo(\"bar\"));"]
+}

test/input/issue-1242/bar.es5

@@ -0,0 +1,4 @@
+function bar(x) {
+    var triple = x * (2 + 1);
+    return triple;
+}

test/input/issue-1242/baz.es5

@@ -0,0 +1,4 @@
+function baz(x) {
+    var half = x / 2;
+    return half;
+}

test/input/issue-1242/foo.es5

@@ -0,0 +1,5 @@
+var print = console.log.bind(console);
+function foo(x) {
+    var twice = x * 2;
+    print('Foo:', twice);
+}

test/input/issue-1242/qux.js

@@ -0,0 +1,4 @@
+var a = bar(1+2);
+var b = baz(3+9);
+print('q' + 'u' + 'x', a, b);
+foo(5+6);

test/input/issue-1323/sample.js

@@ -0,0 +1,7 @@
+var bar = (function () {
+    function foo (bar) {
+        return bar;
+    }
+
+    return foo;
+})();

test/input/issue-1431/sample.js

@@ -0,0 +1,14 @@
+function f(x) {
+    return function() {
+        function n(a) {
+            return a * a;
+        }
+        return x(n);
+    };
+}
+
+function g(op) {
+    return op(1) + op(2);
+}
+
+console.log(f(g)() == 5);

test/input/issue-1482/bracketize.js

@@ -0,0 +1,73 @@
+if (x) {
+    foo();
+}
+
+if (x) {
+    foo();
+} else {
+    baz();
+}
+
+if (x) {
+    foo();
+} else if (y) {
+    bar();
+} else {
+    baz();
+}
+
+if (x) {
+    if (y) {
+        foo();
+    } else {
+        bar();
+    }
+} else {
+    baz();
+}
+
+if (x) {
+    foo();
+} else if (y) {
+    bar();
+} else if (z) {
+    baz();
+} else {
+    moo();
+}
+
+function f() {
+    if (x) {
+        foo();
+    }
+    if (x) {
+        foo();
+    } else {
+        baz();
+    }
+    if (x) {
+        foo();
+    } else if (y) {
+        bar();
+    } else {
+        baz();
+    }
+    if (x) {
+        if (y) {
+            foo();
+        } else {
+            bar();
+        }
+    } else {
+        baz();
+    }
+    if (x) {
+        foo();
+    } else if (y) {
+        bar();
+    } else if (z) {
+        baz();
+    } else {
+        moo();
+    }
+}