Merge pull request #1923 from alexlamsl/harmony-v3.0.4

Merging from master for 3.0.4

.travis.yml

@@ -1,14 +1,12 @@
 language: node_js
+before_install: "npm install -g npm"
 node_js:
     - "0.10"
     - "0.12"
     - "4"
     - "6"
-    - "8"
 env:
     - UGLIFYJS_TEST_ALL=1
 matrix:
   fast_finish: true
 sudo: false
-cache:
-  directories: tmp

README.md

@@ -1,14 +1,12 @@
-UglifyJS 3
-==========
+uglify-es
+=========
+[![Build Status](https://travis-ci.org/mishoo/UglifyJS2.svg)](https://travis-ci.org/mishoo/UglifyJS2)
 
-UglifyJS is a JavaScript parser, minifier, compressor and beautifier toolkit.
+**uglify-es** is an ECMAScript 2015 parser, minifier, compressor and beautifier toolkit.
 
 #### Note:
-- **`uglify-js@3` has a simplified [API](#api-reference) and [CLI](#command-line-usage) that is not backwards compatible with [`uglify-js@2`](https://github.com/mishoo/UglifyJS2/tree/v2.x)**.
-- **Documentation for UglifyJS `2.x` releases can be found [here](https://github.com/mishoo/UglifyJS2/tree/v2.x)**.
-- `uglify-js` only supports ECMAScript 5 (ES5).
-- Those wishing to minify
-ES2015+ (ES6+) should use the `npm` package [**uglify-es**](https://github.com/mishoo/UglifyJS2/tree/harmony).
+- **The `uglify-es` API and CLI is compatible with `uglify-js@3.x`.**
+- **`uglify-es` is not backwards compatible with the `uglify-js@2.x` API and CLI.**
 
 Install
 -------
@@ -18,13 +16,14 @@ First make sure you have installed the latest version of [node.js](http://nodejs
 
 From NPM for use as a command line app:
 
-    npm install uglify-js -g
+    npm install uglify-es -g
 
 From NPM for programmatic use:
 
-    npm install uglify-js
+    npm install uglify-es
 
-# Command line usage
+Usage
+-----
 
     uglifyjs [input files] [options]
 
@@ -41,11 +40,10 @@ a double dash to prevent input files being used as option arguments:
 
     uglifyjs --compress --mangle -- input.js
 
-### Command line options
+The available options are:
 
 ```
     -h, --help                  Print usage information.
-                                `--help options` for details on available options.
     -V, --version               Print version number.
     -p, --parse <options>       Specify parser options:
                                 `acorn`  Use Acorn for parsing.
@@ -127,8 +125,8 @@ a double dash to prevent input files being used as option arguments:
                                         the source map.
                                 `url`  If specified, path to the source map to append in
                                        `//# sourceMappingURL`.
-    --timings                   Display operations run time on STDERR.
-    --toplevel                  Compress and/or mangle variables in top level scope.
+    --stats                     Display operations run time on STDERR.
+    --toplevel                  Compress and/or mangle variables in toplevel scope.
     --verbose                   Print diagnostic messages.
     --warn                      Print warning messages.
     --wrap <name>               Embed everything in a big function, making the
@@ -141,7 +139,7 @@ a double dash to prevent input files being used as option arguments:
 Specify `--output` (`-o`) to declare the output file.  Otherwise the output
 goes to STDOUT.
 
-## CLI source map options
+## Source map options
 
 UglifyJS can generate a source map file, which is highly useful for
 debugging your compressed JavaScript.  To get a source map, pass
@@ -185,25 +183,12 @@ To use this feature pass `--source-map content="/path/to/input/source.map"`
 or `--source-map content=inline` if the source map is included inline with
 the sources.
 
-## CLI compress options
-
-You need to pass `--compress` (`-c`) to enable the compressor.  Optionally
-you can pass a comma-separated list of [compress options](#compress-options).
-
-Options are in the form `foo=bar`, or just `foo` (the latter implies
-a boolean option that you want to set `true`; it's effectively a
-shortcut for `foo=true`).
-
-Example:
-
-    uglifyjs file.js -c toplevel,sequences=false
-
-## CLI mangle options
+## Mangler options
 
 To enable the mangler you need to pass `--mangle` (`-m`).  The following
 (comma-separated) options are supported:
 
-- `toplevel` — mangle names declared in the top level scope (disabled by
+- `toplevel` — mangle names declared in the toplevel scope (disabled by
   default).
 
 - `eval` — mangle names visible in scopes where `eval` or `with` are used
@@ -217,56 +202,26 @@ comma-separated list of names.  For example:
 
 to prevent the `require`, `exports` and `$` names from being changed.
 
-### CLI mangling property names (`--mangle-props`)
+### Mangling property names (`--mangle-props`)
 
-**Note:** THIS WILL PROBABLY BREAK YOUR CODE.  Mangling property names
-is a separate step, different from variable name mangling.  Pass
-`--mangle-props` to enable it.  It will mangle all properties in the
-input code with the exception of built in DOM properties and properties
-in core javascript classes.  For example:
+**Note:** this will probably break your code.  Mangling property names is a
+separate step, different from variable name mangling.  Pass
+`--mangle-props`.  It will mangle all properties that are seen in some
+object literal, or that are assigned to.  For example:
 
-```javascript
-// example.js
+```js
 var x = {
-    baz_: 0,
-    foo_: 1,
-    calc: function() {
-        return this.foo_ + this.baz_;
-    }
+  foo: 1
 };
-x.bar_ = 2;
-x["baz_"] = 3;
-console.log(x.calc());
-```
-Mangle all properties (except for javascript `builtins`):
-```bash
-$ uglifyjs example.js -c -m --mangle-props
-```
-```javascript
-var x={o:0,_:1,l:function(){return this._+this.o}};x.t=2,x.o=3,console.log(x.l());
-```
-Mangle all properties except for `reserved` properties:
-```bash
-$ uglifyjs example.js -c -m --mangle-props reserved=[foo_,bar_]
-```
-```javascript
-var x={o:0,foo_:1,_:function(){return this.foo_+this.o}};x.bar_=2,x.o=3,console.log(x._());
-```
-Mangle all properties matching a `regex`:
-```bash
-$ uglifyjs example.js -c -m --mangle-props regex=/_$/
-```
-```javascript
-var x={o:0,_:1,calc:function(){return this._+this.o}};x.l=2,x.o=3,console.log(x.calc());
+
+x.bar = 2;
+x["baz"] = 3;
+x[condition ? "moo" : "boo"] = 4;
+console.log(x.something());
 ```
 
-Combining mangle properties options:
-```bash
-$ uglifyjs example.js -c -m --mangle-props regex=/_$/,reserved=[bar_]
-```
-```javascript
-var x={o:0,_:1,calc:function(){return this._+this.o}};x.bar_=2,x.o=3,console.log(x.calc());
-```
+In the above code, `foo`, `bar`, `baz`, `moo` and `boo` will be replaced
+with single characters, while `something()` will be left as is.
 
 In order for this to be of any use, we avoid mangling standard JS names by
 default (`--mangle-props builtins` to override).
@@ -275,7 +230,7 @@ A default exclusion file is provided in `tools/domprops.json` which should
 cover most standard JS and DOM properties defined in various browsers.  Pass
 `--mangle-props domprops` to disable this feature.
 
-A regular expression can be used to define which property names should be
+You can also use a regular expression to define which property names should be
 mangled.  For example, `--mangle-props regex=/^_/` will only mangle property
 names that start with an underscore.
 
@@ -285,10 +240,10 @@ mangled to the same name in all of them.  For this, pass `--name-cache filename.
 and UglifyJS will maintain these mappings in a file which can then be reused.
 It should be initially empty.  Example:
 
-```bash
-$ rm -f /tmp/cache.json  # start fresh
-$ uglifyjs file1.js file2.js --mangle-props --name-cache /tmp/cache.json -o part1.js
-$ uglifyjs file3.js file4.js --mangle-props --name-cache /tmp/cache.json -o part2.js
+```
+rm -f /tmp/cache.json  # start fresh
+uglifyjs file1.js file2.js --mangle-props --name-cache /tmp/cache.json -o part1.js
+uglifyjs file3.js file4.js --mangle-props --name-cache /tmp/cache.json -o part2.js
 ```
 
 Now, `part1.js` and `part2.js` will be consistent with each other in terms
@@ -297,29 +252,18 @@ 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 keep_quoted`)
+#### Mangling unquoted names (`--mangle-props keep_quoted`)
 
 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:
 
-```javascript
-// stuff.js
-var o = {
-    "foo": 1,
-    bar: 3
-};
-o.foo += o.bar;
-console.log(o.foo);
 ```
-```bash
-$ uglifyjs stuff.js --mangle-props keep_quoted -c -m
-```
-```javascript
-var o={foo:1,o:3};o.foo+=o.o,console.log(o.foo);
+$ echo 'var o={"foo":1, bar:3}; o.foo += o.bar; console.log(o.foo);' | uglifyjs --mangle-props keep_quoted -mc
+var o={foo:1,a:3};o.foo+=o.a,console.log(o.foo);
 ```
 
-### Debugging property name mangling
+#### 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`
@@ -327,13 +271,6 @@ 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.
 
-```bash
-$ uglifyjs stuff.js --mangle-props debug -c -m
-```
-```javascript
-var o={_$foo$_:1,_$bar$_:3};o._$foo$_+=o._$bar$_,console.log(o._$foo$_);
-```
-
 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
@@ -341,211 +278,12 @@ 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
 
-# API Reference
-
-Assuming installation via NPM, you can load UglifyJS in your application
-like this:
-```javascript
-var UglifyJS = require("uglify-js");
-```
-
-There is a single high level function, **`minify(code, options)`**,
-which will perform all minification [phases](#minify-options) in a configurable
-manner. By default `minify()` will enable the options [`compress`](#compress-options)
-and [`mangle`](#mangle-options). Example:
-```javascript
-var code = "function add(first, second) { return first + second; }";
-var result = UglifyJS.minify(code);
-console.log(result.error); // runtime error, or `undefined` if no error
-console.log(result.code);  // minified output: function add(n,d){return n+d}
-```
-
-You can `minify` more than one JavaScript file at a time by using an object
-for the first argument where the keys are file names and the values are source
-code:
-```javascript
-var code = {
-    "file1.js": "function add(first, second) { return first + second; }",
-    "file2.js": "console.log(add(1 + 2, 3 + 4));"
-};
-var result = UglifyJS.minify(code);
-console.log(result.code);
-// function add(d,n){return d+n}console.log(add(3,7));
-```
-
-The `toplevel` option:
-```javascript
-var code = {
-    "file1.js": "function add(first, second) { return first + second; }",
-    "file2.js": "console.log(add(1 + 2, 3 + 4));"
-};
-var options = { toplevel: true };
-var result = UglifyJS.minify(code, options);
-console.log(result.code);
-// console.log(function(n,o){return n+o}(3,7));
-```
-
-An example of a combination of `minify()` options:
-```javascript
-var code = {
-    "file1.js": "function add(first, second) { return first + second; }",
-    "file2.js": "console.log(add(1 + 2, 3 + 4));"
-};
-var options = {
-    toplevel: true,
-    compress: {
-        global_defs: {
-            "@console.log": "alert"
-        },
-        passes: 2
-    },
-    output: {
-        beautify: false,
-        preamble: "/* uglified */"
-    }
-};
-var result = UglifyJS.minify(code, options);
-console.log(result.code);
-// /* uglified */
-// alert(10);"
-```
-
-To produce warnings:
-```javascript
-var code = "function f(){ var u; return 2 + 3; }";
-var options = { warnings: true };
-var result = UglifyJS.minify(code, options);
-console.log(result.error);    // runtime error, `undefined` in this case
-console.log(result.warnings); // [ 'Dropping unused variable u [0:1,18]' ]
-console.log(result.code);     // function f(){return 5}
-```
-
-An error example:
-```javascript
-var result = UglifyJS.minify({"foo.js" : "if (0) else console.log(1);"});
-console.log(JSON.stringify(result.error));
-// {"message":"Unexpected token: keyword (else)","filename":"foo.js","line":1,"col":7,"pos":7}
-```
-Note: unlike `uglify-js@2.x`, the `3.x` API does not throw errors. To
-achieve a similar effect one could do the following:
-```javascript
-var result = UglifyJS.minify(code, options);
-if (result.error) throw result.error;
-```
-
-## Minify options
-
-- `warnings` (default `false`) — pass `true` to return compressor warnings
-  in `result.warnings`. Use the value `"verbose"` for more detailed warnings.
-
-- `parse` (default `{}`) — pass an object if you wish to specify some
-  additional [parse options](#parse-options).
-
-- `compress` (default `{}`) — pass `false` to skip compressing entirely.
-  Pass an object to specify custom [compress options](#compress-options).
-
-- `mangle` (default `true`) — pass `false` to skip mangling names, or pass
-  an object to specify [mangle options](#mangle-options) (see below).
-
-  - `mangle.properties` (default `false`) — a subcategory of the mangle option.
-    Pass an object to specify custom [mangle property options](#mangle-properties-options).
-
-- `output` (default `null`) — pass an object if you wish to specify
-  additional [output options](#output-options).  The defaults are optimized
-  for best compression.
-
-- `sourceMap` (default `false`) - pass an object if you wish to specify
-  [source map options](#source-map-options).
-
-- `toplevel` (default `false`) - set to `true` if you wish to enable top level
-  variable and function name mangling and to drop unused variables and functions.
-
-- `ie8` (default `false`) - set to `true` to support IE8.
-
-## Minify options structure
-
-```javascript
-{
-    warnings: false,
-    parse: {
-        // parse options
-    },
-    compress: {
-        // compress options
-    },
-    mangle: {
-        // mangle options
-
-        properties: {
-            // mangle property options
-        }
-    },
-    output: {
-        // output options
-    },
-    sourceMap: {
-        // source map options
-    },
-    toplevel: false,
-    ie8: false,
-}
-```
-
-### Source map options
-
-To generate a source map:
-```javascript
-var result = UglifyJS.minify({"file1.js": "var a = function() {};"}, {
-    sourceMap: {
-        filename: "out.js",
-        url: "out.js.map"
-    }
-});
-console.log(result.code); // minified output
-console.log(result.map);  // source map
-```
-
-Note that the source map is not saved in a file, it's just returned in
-`result.map`.  The value passed for `sourceMap.url` is only used to set
-`//# sourceMappingURL=out.js.map` in `result.code`. The value of
-`filename` is only used to set `file` attribute (see [the spec][sm-spec])
-in source map file.
-
-You can set option `sourceMap.url` to be `"inline"` and source map will
-be appended to code.
-
-You can also specify sourceRoot property to be included in source map:
-```javascript
-var result = UglifyJS.minify({"file1.js": "var a = function() {};"}, {
-    sourceMap: {
-        root: "http://example.com/src",
-        url: "out.js.map"
-    }
-});
-```
-
-If you're compressing compiled JavaScript and have a source map for it, you
-can use `sourceMap.content`:
-```javascript
-var result = UglifyJS.minify({"compiled.js": "compiled code"}, {
-    sourceMap: {
-        content: "content from compiled.js.map",
-        url: "minified.js.map"
-    }
-});
-// same as before, it returns `code` and `map`
-```
-
-If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.url`.
-
-## Parse options
-
-- `bare_returns` (default `false`) -- support top level `return` statements
-- `html5_comments` (default `true`)
-- `shebang` (default `true`) -- support `#!command` as the first line
-
-## Compress options
+You need to pass `--compress` (`-c`) to enable the compressor.  Optionally
+you can pass a comma-separated list of options.  Options are in the form
+`foo=bar`, or just `foo` (the latter implies a boolean option that you want
+to set `true`; it's effectively a shortcut for `foo=true`).
 
 - `sequences` (default: true) -- join consecutive simple statements using the
   comma operator.  May be set to a positive integer to specify the maximum number
@@ -572,18 +310,12 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   comparison are switching. Compression only works if both `comparisons` and
   `unsafe_comps` are both set to true.
 
-- `unsafe_Func` (default: false) -- compress and mangle `Function(args, code)`
-  when both `args` and `code` are string literals.
-
 - `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)`
 
-- `unsafe_regexp` (default: false) -- enable substitutions of variables with
-  `RegExp` values the same way as if they are constants.
-
 - `conditionals` -- apply optimizations for `if`-s and conditional
   expressions
 
@@ -603,7 +335,7 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   assignments do not count as references unless set to `"keep_assign"`)
 
 - `toplevel` -- drop unreferenced functions (`"funcs"`) and/or variables (`"vars"`)
-  in the top level scope (`false` by default, `true` to drop both unreferenced
+  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`
@@ -616,15 +348,13 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 
 - `if_return` -- optimizations for if/return and if/continue
 
-- `inline` -- embed simple functions
-
 - `join_vars` -- join consecutive `var` statements
 
 - `cascade` -- small optimization for sequences, transform `x, x` into `x`
   and `x = something(), x` into `x = something()`
 
-- `collapse_vars` -- Collapse single-use non-constant variables - side
-  effects permitting.
+- `collapse_vars` -- Collapse single-use `var` and `const` definitions
+  when possible.
 
 - `reduce_vars` -- Improve optimization on variables assigned with and
   used as constant values.
@@ -669,152 +399,14 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   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 with a maximum of 3.
-  In some cases more than one pass leads to further compressed code.  Keep in
-  mind more passes will take more time.
+- `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.
 
-- `side_effects` -- default `true`. Pass `false` to disable potentially dropping
-  functions marked as "pure".  A function call is marked as "pure" if a comment
-  annotation `/*@__PURE__*/` or `/*#__PURE__*/` immediately precedes the call. For
-  example: `/*@__PURE__*/foo();`
-
-## Mangle options
-
-- `reserved` (default `[]`). Pass an array of identifiers that should be
-  excluded from mangling. Example: `["foo", "bar"]`.
-
-- `toplevel` (default `false`). Pass `true` to mangle names declared in the
-  top level scope.
-
-- `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](#compress-options).
-
-- `eval` (default `false`). Pass `true` to mangle names visible in scopes
-  where `eval` or `with` are used.
-
-Examples:
-
-```javascript
-// test.js
-var globalVar;
-function funcName(firstLongName, anotherLongName) {
-    var myVariable = firstLongName +  anotherLongName;
-}
-```
-```javascript
-var code = fs.readFileSync("test.js", "utf8");
-
-UglifyJS.minify(code).code;
-// 'function funcName(a,n){}var globalVar;'
-
-UglifyJS.minify(code, { mangle: { reserved: ['firstLongName'] } }).code;
-// 'function funcName(firstLongName,a){}var globalVar;'
-
-UglifyJS.minify(code, { mangle: { toplevel: true } }).code;
-// 'function n(n,a){}var a;'
-```
-
-### Mangle properties options
-
-- `reserved` (default: `[]`) -- Do not mangle property names listed in the
-  `reserved` array.
-- `regex` (default: `null`) -— Pass a RegExp literal to only mangle property
-  names matching the regular expression.
-- `keep_quoted` (default: `false`) -— Only mangle unquoted property names.
-- `debug` (default: `false`) -— Mangle names with the original name still present.
-  Pass an empty string `""` to enable, or a non-empty string to set the debug suffix.
-- `builtins` (default: `false`) -- Use `true` to allow the mangling of builtin
-  DOM properties. Not recommended to override this setting.
-
-## Output options
-
-The code generator tries to output shortest code possible by default.  In
-case you want beautified output, pass `--beautify` (`-b`).  Optionally you
-can pass additional arguments that control the code output:
-
-- `ascii_only` (default `false`) -- escape Unicode characters in strings and
-  regexps (affects directives with non-ascii characters becoming invalid)
-- `beautify` (default `true`) -- whether to actually beautify the output.
-  Passing `-b` will set this to true, but you might need to pass `-b` even
-  when you want to generate minified code, in order to specify additional
-  arguments, so you can use `-b beautify=false` to override it.
-- `bracketize` (default `false`) -- always insert brackets in `if`, `for`,
-  `do`, `while` or `with` statements, even if their body is a single
-  statement.
-- `comments` (default `false`) -- pass `true` or `"all"` to preserve all
-  comments, `"some"` to preserve some comments, a regular expression string
-  (e.g. `/^!/`) or a function.
-- `indent_level` (default 4)
-- `indent_start` (default 0) -- prefix all lines by that many spaces
-- `inline_script` (default `false`) -- escape the slash in occurrences of
-  `</script` in strings
-- `keep_quoted_props` (default `false`) -- when turned on, prevents stripping
-  quotes from property names in object literals.
-- `max_line_len` (default `false`) -- maximum line length (for uglified code)
-- `preamble` (default `null`) -- when passed it must be a string and
-  it will be prepended to the output literally.  The source map will
-  adjust for this text.  Can be used to insert a comment containing
-  licensing information, for example.
-- `preserve_line` (default `false`) -- pass `true` to preserve lines, but it
-  only works if `beautify` is set to `false`.
-- `quote_keys` (default `false`) -- pass `true` to quote all keys in literal
-  objects
-- `quote_style` (default `0`) -- preferred quote style for strings (affects
-  quoted property names and directives as well):
-  - `0` -- prefers double quotes, switches to single quotes when there are
-    more double quotes in the string itself. `0` is best for gzip size.
-  - `1` -- always use single quotes
-  - `2` -- always use double quotes
-  - `3` -- always use the original quotes
-- `semicolons` (default `true`) -- separate statements with semicolons.  If
-  you pass `false` then whenever possible we will use a newline instead of a
-  semicolon, leading to more readable output of uglified code (size before
-  gzip could be smaller; size after gzip insignificantly larger).
-- `shebang` (default `true`) -- preserve shebang `#!` in preamble (bash scripts)
-- `width` (default 80) -- only takes effect when beautification is on, this
-  specifies an (orientative) line width that the beautifier will try to
-  obey.  It refers to the width of the line text (excluding indentation).
-  It doesn't work very well currently, but it does make the code generated
-  by UglifyJS more readable.
-- `wrap_iife` (default `false`) -- pass `true` to wrap immediately invoked
-  function expressions. See
-  [#640](https://github.com/mishoo/UglifyJS2/issues/640) for more details.
-
-# Miscellaneous
-
-### Keeping copyright notices or other comments
-
-You can pass `--comments` to retain certain comments in the output.  By
-default it will keep JSDoc-style comments that contain "@preserve",
-"@license" or "@cc_on" (conditional compilation for IE).  You can pass
-`--comments all` to keep all the comments, or a valid JavaScript regexp to
-keep only comments that match this regexp.  For example `--comments /^!/`
-will keep comments like `/*! Copyright Notice */`.
-
-Note, however, that there might be situations where comments are lost.  For
-example:
-```javascript
-function f() {
-    /** @preserve Foo Bar */
-    function g() {
-        // this function is never called
-    }
-    return something();
-}
-```
-
-Even though it has "@preserve", the comment will be lost because the inner
-function `g` (which is the AST node to which the comment is attached to) is
-discarded by the compressor as not referenced.
-
-The safest comments where to place copyright information (or other info that
-needs to be kept in the output) are comments attached to toplevel nodes.
-
-### The `unsafe` `compress` option
+### The `unsafe` option
 
 It enables some transformations that *might* break code logic in certain
 contrived cases, but should be fine for most code.  You might want to try it
@@ -838,7 +430,7 @@ scope).  For example if you pass `--define DEBUG=false` then, coupled with
 dead code removal UglifyJS will discard the following from the output:
 ```javascript
 if (DEBUG) {
-    console.log("debug stuff");
+	console.log("debug stuff");
 }
 ```
 
@@ -852,8 +444,8 @@ Another way of doing that is to declare your globals as constants in a
 separate file and include it into the build.  For example you can have a
 `build/defines.js` file with the following:
 ```javascript
-var DEBUG = false;
-var PRODUCTION = true;
+const DEBUG = false;
+const PRODUCTION = true;
 // etc.
 ```
 
@@ -867,13 +459,12 @@ code as usual.  The build will contain the `const` declarations if you use
 them. If you are targeting < ES6 environments which does not support `const`,
 using `var` with `reduce_vars` (enabled by default) should suffice.
 
-### Conditional compilation API
-
+#### Conditional compilation, API
 You can also use conditional compilation via the programmatic API. With the difference that the
 property name is `global_defs` and is a compressor property:
 
-```javascript
-var result = UglifyJS.minify(fs.readFileSync("input.js", "utf8"), {
+```js
+uglifyJS.minify(fs.readFileSync("input.js", "utf8"), {
     compress: {
         dead_code: true,
         global_defs: {
@@ -883,72 +474,84 @@ var result = UglifyJS.minify(fs.readFileSync("input.js", "utf8"), {
 });
 ```
 
-To replace an identifier with an arbitrary non-constant expression it is
-necessary to prefix the `global_defs` key with `"@"` to instruct UglifyJS
-to parse the value as an expression:
+## Beautifier options
+
+The code generator tries to output shortest code possible by default.  In
+case you want beautified output, pass `--beautify` (`-b`).  Optionally you
+can pass additional arguments that control the code output:
+
+- `beautify` (default `true`) -- whether to actually beautify the output.
+  Passing `-b` will set this to true, but you might need to pass `-b` even
+  when you want to generate minified code, in order to specify additional
+  arguments, so you can use `-b beautify=false` to override it.
+- `indent_level` (default 4)
+- `indent_start` (default 0) -- prefix all lines by that many spaces
+- `quote_keys` (default `false`) -- pass `true` to quote all keys in literal
+  objects
+- `space_colon` (default `true`) -- insert a space after the colon signs
+- `ascii_only` (default `false`) -- escape Unicode characters in strings and
+  regexps (affects directives with non-ascii characters becoming invalid)
+- `inline_script` (default `false`) -- escape the slash in occurrences of
+  `</script` in strings
+- `width` (default 80) -- only takes effect when beautification is on, this
+  specifies an (orientative) line width that the beautifier will try to
+  obey.  It refers to the width of the line text (excluding indentation).
+  It doesn't work very well currently, but it does make the code generated
+  by UglifyJS more readable.
+- `max_line_len` (default 32000) -- maximum line length (for uglified code)
+- `bracketize` (default `false`) -- always insert brackets in `if`, `for`,
+  `do`, `while` or `with` statements, even if their body is a single
+  statement.
+- `semicolons` (default `true`) -- separate statements with semicolons.  If
+  you pass `false` then whenever possible we will use a newline instead of a
+  semicolon, leading to more readable output of uglified code (size before
+  gzip could be smaller; size after gzip insignificantly larger).
+- `preamble` (default `null`) -- when passed it must be a string and
+  it will be prepended to the output literally.  The source map will
+  adjust for this text.  Can be used to insert a comment containing
+  licensing information, for example.
+- `quote_style` (default `0`) -- preferred quote style for strings (affects
+  quoted property names and directives as well):
+  - `0` -- prefers double quotes, switches to single quotes when there are
+    more double quotes in the string itself.
+  - `1` -- always use single quotes
+  - `2` -- always use double quotes
+  - `3` -- always use the original quotes
+- `keep_quoted_props` (default `false`) -- when turned on, prevents stripping
+  quotes from property names in object literals.
+- `ecma` (default `5`) -- set output printing mode.  This will only change the
+  output in direct control of the beautifier.  Non-compatible features in the
+  abstract syntax tree will still be outputted as is.
+
+### Keeping copyright notices or other comments
+
+You can pass `--comments` to retain certain comments in the output.  By
+default it will keep JSDoc-style comments that contain "@preserve",
+"@license" or "@cc_on" (conditional compilation for IE).  You can pass
+`--comments all` to keep all the comments, or a valid JavaScript regexp to
+keep only comments that match this regexp.  For example `--comments /^!/`
+will keep comments like `/*! Copyright Notice */`.
+
+Note, however, that there might be situations where comments are lost.  For
+example:
 ```javascript
-UglifyJS.minify("alert('hello');", {
-    compress: {
-        global_defs: {
-            "@alert": "console.log"
-        }
-    }
-}).code;
-// returns: 'console.log("hello");'
+function f() {
+	/** @preserve Foo Bar */
+	function g() {
+	  // this function is never called
+	}
+	return something();
+}
 ```
 
-Otherwise it would be replaced as string literal:
-```javascript
-UglifyJS.minify("alert('hello');", {
-    compress: {
-        global_defs: {
-            "alert": "console.log"
-        }
-    }
-}).code;
-// returns: '"console.log"("hello");'
-```
+Even though it has "@preserve", the comment will be lost because the inner
+function `g` (which is the AST node to which the comment is attached to) is
+discarded by the compressor as not referenced.
 
-### Using native Uglify AST with `minify()`
-```javascript
-// example: parse only, produce native Uglify AST
+The safest comments where to place copyright information (or other info that
+needs to be kept in the output) are comments attached to toplevel nodes.
 
-var result = UglifyJS.minify(code, {
-    parse: {},
-    compress: false,
-    mangle: false,
-    output: {
-        ast: true,
-        code: false  // optional - faster if false
-    }
-});
-
-// result.ast contains native Uglify AST
-```
-```javascript
-// example: accept native Uglify AST input and then compress and mangle
-//          to produce both code and native AST.
-
-var result = UglifyJS.minify(ast, {
-    compress: {},
-    mangle: {},
-    output: {
-        ast: true,
-        code: true  // optional - faster if false
-    }
-});
-
-// result.ast contains native Uglify AST
-// result.code contains the minified code in string form.
-```
-
-### Working with Uglify AST
-
-Transversal and transformation of the native AST can be performed through
-[`TreeWalker`](http://lisperator.net/uglifyjs/walk) and
-[`TreeTransformer`](http://lisperator.net/uglifyjs/transform) respectively.
-
-### ESTree / SpiderMonkey AST
+## Support for the SpiderMonkey AST
 
 UglifyJS has its own abstract syntax tree format; for
 [practical reasons](http://lisperator.net/blog/uglifyjs-why-not-switching-to-spidermonkey-ast/)
@@ -976,5 +579,141 @@ Acorn is really fast (e.g. 250ms instead of 380ms on some 650K code), but
 converting the SpiderMonkey tree that Acorn produces takes another 150ms so
 in total it's a bit more than just using UglifyJS's own parser.
 
+API Reference
+-------------
+
+Assuming installation via NPM, you can load UglifyJS in your application
+like this:
+```javascript
+var UglifyJS = require("uglify-es");
+```
+
+There is a single toplevel function, `minify(files, options)`, which will
+performs all the steps in a configurable manner.
+Example:
+```javascript
+var result = UglifyJS.minify("var b = function() {};");
+console.log(result.code);  // minified output
+console.log(result.error); // runtime error
+```
+
+You can also compress multiple files:
+```javascript
+var result = UglifyJS.minify({
+  "file1.js": "var a = function() {};",
+  "file2.js": "var b = function() {};"
+});
+console.log(result.code);
+```
+
+To generate a source map:
+```javascript
+var result = UglifyJS.minify({"file1.js": "var a = function() {};"}, {
+  sourceMap: {
+    filename: "out.js",
+    url: "out.js.map"
+  }
+});
+console.log(result.code); // minified output
+console.log(result.map);  // source map
+```
+
+Note that the source map is not saved in a file, it's just returned in
+`result.map`.  The value passed for `sourceMap.url` is only used to set
+`//# sourceMappingURL=out.js.map` in `result.code`. The value of
+`filename` is only used to set `file` attribute (see [the spec][sm-spec])
+in source map file.
+
+You can set option `sourceMap.url` to be `"inline"` and source map will
+be appended to code.
+
+You can also specify sourceRoot property to be included in source map:
+```javascript
+var result = UglifyJS.minify({"file1.js": "var a = function() {};"}, {
+  sourceMap: {
+    root: "http://example.com/src",
+    url: "out.js.map"
+  }
+});
+```
+
+If you're compressing compiled JavaScript and have a source map for it, you
+can use `sourceMap.content`:
+```javascript
+var result = UglifyJS.minify({"compiled.js": "compiled code"}, {
+  sourceMap: {
+    content: "content from compiled.js.map",
+    url: "minified.js.map"
+  }
+});
+// same as before, it returns `code` and `map`
+```
+
+If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.url`.
+
+Other options:
+
+- `warnings` (default `false`) — pass `true` to display compressor warnings.
+
+- `mangle` (default `true`) — pass `false` to skip mangling names, or pass
+  an object to specify mangling options (see below).
+
+- `mangleProperties` (default `false`) — pass an object to specify custom
+  mangle property options.
+
+- `output` (default `null`) — pass an object if you wish to specify
+  additional [output options](#beautifier-options).  The defaults are optimized
+  for best compression.
+
+- `compress` (default `{}`) — pass `false` to skip compressing entirely.
+  Pass an object to specify custom [compressor options](#compressor-options).
+
+- `parse` (default {}) — pass an object if you wish to specify some
+  additional [parser options](#the-parser).
+
+##### mangle
+
+- `reserved` - pass an array of identifiers that should be excluded from mangling
+
+- `toplevel` — mangle names declared in the toplevel scope (disabled by
+default).
+
+- `eval` — mangle names visible in scopes where eval or with are used
+(disabled by default).
+
+- `keep_fnames` -- default `false`.  Pass `true` to not mangle
+function names.  Useful for code relying on `Function.prototype.name`.
+See also: the `keep_fnames` [compress option](#compressor-options).
+
+Examples:
+
+```javascript
+// test.js
+var globalVar;
+function funcName(firstLongName, anotherLongName)
+{
+    var myVariable = firstLongName +  anotherLongName;
+}
+```
+```javascript
+var code = fs.readFileSync("test.js", "utf8");
+
+UglifyJS.minify(code).code;
+// 'function funcName(a,n){}var globalVar;'
+
+UglifyJS.minify(code, { mangle: { reserved: ['firstLongName'] } }).code;
+// 'function funcName(firstLongName,a){}var globalVar;'
+
+UglifyJS.minify(code, { mangle: { toplevel: true } }).code;
+// 'function n(n,a){}var a;'
+```
+
+##### mangle.properties options
+
+- `regex` — Pass a RegExp to only mangle certain names
+- `keep_quoted` — Only mangle unquoted property names
+- `debug` — Mangle names with the original name still present. Defaults to `false`.
+  Pass an empty string to enable, or a non-empty string to set the suffix.
+
 [acorn]: https://github.com/ternjs/acorn
 [sm-spec]: https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k

bin/uglifyjs

@@ -21,20 +21,10 @@ var options = {
     compress: false,
     mangle: false
 };
-program.version(info.name + " " + info.version);
+program._name = info.name;
+program.version(info.version);
 program.parseArgv = program.parse;
 program.parse = undefined;
-if (process.argv.indexOf("ast") >= 0) program.helpInformation = UglifyJS.describe_ast;
-else if (process.argv.indexOf("options") >= 0) program.helpInformation = function() {
-    var text = [];
-    var options = UglifyJS.default_options();
-    for (var option in options) {
-        text.push("--" + (option == "output" ? "beautify" : option == "sourceMap" ? "source-map" : option) + " options:");
-        text.push(format_object(options[option]));
-        text.push("");
-    }
-    return text.join("\n");
-};
 program.option("-p, --parse <options>", "Specify parser options.", parse_js("parse", true));
 program.option("-c, --compress [options]", "Enable compressor/specify compressor options.", parse_js("compress", true));
 program.option("-m, --mangle [options]", "Mangle names/specify mangler options.", parse_js("mangle", true));
@@ -49,7 +39,7 @@ program.option("--keep-fnames", "Do not mangle/drop function names. Useful for c
 program.option("--name-cache <file>", "File to hold mangled name mappings.");
 program.option("--self", "Build UglifyJS as a library (implies --wrap UglifyJS)");
 program.option("--source-map [options]", "Enable source map/specify source map options.", parse_source_map());
-program.option("--timings", "Display operations run time on STDERR.")
+program.option("--stats", "Display operations run time on STDERR.")
 program.option("--toplevel", "Compress and/or mangle variables in toplevel scope.");
 program.option("--verbose", "Print diagnostic messages.");
 program.option("--warn", "Print warning messages.");
@@ -125,10 +115,10 @@ if (program.output == "ast") {
     };
 }
 if (program.parse) {
-    if (!program.parse.acorn && !program.parse.spidermonkey) {
+    if (program.parse.acorn || program.parse.spidermonkey) {
+        if (program.sourceMap) fatal("ERROR: inline source map only works with built-in parser");
+    } else {
         options.parse = program.parse;
-    } else if (program.sourceMap && program.sourceMap.content == "inline") {
-        fatal("ERROR: inline source map only works with built-in parser");
     }
 }
 var convert_path = function(name) {
@@ -150,7 +140,7 @@ if (program.verbose) {
 }
 if (program.self) {
     if (program.args.length) {
-        print_error("WARN: Ignoring input files since --self was passed");
+        console.error("WARN: Ignoring input files since --self was passed");
     }
     if (!options.wrap) options.wrap = "UglifyJS";
     simple_glob(UglifyJS.FILES).forEach(function(name) {
@@ -180,9 +170,9 @@ function convert_ast(fn) {
 
 function run() {
     UglifyJS.AST_Node.warn_function = function(msg) {
-        print_error("WARN: " + msg);
+        console.error("WARN:", msg);
     };
-    if (program.timings) options.timings = true;
+    if (program.stats) program.stats = Date.now();
     try {
         if (program.parse) {
             if (program.parse.acorn) {
@@ -209,7 +199,7 @@ function run() {
     if (result.error) {
         var ex = result.error;
         if (ex.name == "SyntaxError") {
-            print_error("Parse error at " + ex.filename + ":" + ex.line + "," + ex.col);
+            console.error("Parse error at " + ex.filename + ":" + ex.line + "," + ex.col);
             var col = ex.col;
             var lines = files[ex.filename].split(/\r?\n/);
             var line = lines[ex.line - 1];
@@ -218,22 +208,21 @@ function run() {
                 col = line.length;
             }
             if (line) {
-                var limit = 70;
-                if (col > limit) {
-                    line = line.slice(col - limit);
-                    col = limit;
+                if (col > 40) {
+                    line = line.slice(col - 40);
+                    col = 40;
                 }
-                print_error(line.slice(0, 80));
-                print_error(line.slice(0, col).replace(/\S/g, " ") + "^");
+                console.error(line.slice(0, 80));
+                console.error(line.slice(0, col).replace(/\S/g, " ") + "^");
             }
         }
         if (ex.defs) {
-            print_error("Supported options:");
-            print_error(format_object(ex.defs));
+            console.error("Supported options:");
+            console.error(ex.defs);
         }
         fatal(ex);
     } else if (program.output == "ast") {
-        print(JSON.stringify(result.ast, function(key, value) {
+        console.log(JSON.stringify(result.ast, function(key, value) {
             if (skip_key(key)) return;
             if (value instanceof UglifyJS.AST_Token) return;
             if (value instanceof UglifyJS.Dictionary) return;
@@ -249,7 +238,7 @@ function run() {
             return value;
         }, 2));
     } else if (program.output == "spidermonkey") {
-        print(JSON.stringify(UglifyJS.minify(result.code, {
+        console.log(JSON.stringify(UglifyJS.minify(result.code, {
             compress: false,
             mangle: false,
             output: {
@@ -263,21 +252,19 @@ function run() {
             fs.writeFileSync(program.output + ".map", result.map);
         }
     } else {
-        print(result.code);
+        console.log(result.code);
     }
     if (program.nameCache) {
         fs.writeFileSync(program.nameCache, JSON.stringify(cache, function(key, value) {
             return value instanceof UglifyJS.Dictionary ? value.toObject() : value;
         }));
     }
-    if (result.timings) for (var phase in result.timings) {
-        print_error("- " + phase + ": " + result.timings[phase].toFixed(3) + "s");
-    }
+    if (program.stats) console.error("Elapsed:", Date.now() - program.stats);
 }
 
 function fatal(message) {
     if (message instanceof Error) message = message.stack.replace(/^\S*?Error:/, "ERROR:")
-    print_error(message);
+    console.error(message);
     process.exit(1);
 }
 
@@ -362,7 +349,7 @@ function parse_js(flag, constants) {
                 }
             }));
         } catch(ex) {
-            options[value] = null;
+            fatal("Error parsing arguments for '" + flag + "': " + value);
         }
         return options;
     }
@@ -371,10 +358,10 @@ function parse_js(flag, constants) {
 function parse_source_map() {
     var parse = parse_js("sourceMap", true);
     return function(value, options) {
-        var hasContent = options && "content" in options;
+        var hasContent = options && options.sourceMap && "content" in options.sourceMap;
         var settings = parse(value, options);
         if (!hasContent && settings.content && settings.content != "inline") {
-            print_error("INFO: Using input source map: " + settings.content);
+            console.error("INFO: Using input source map:", settings.content);
             settings.content = read_file(settings.content, settings.content);
         }
         return settings;
@@ -396,25 +383,3 @@ function to_cache(key) {
 function skip_key(key) {
     return skip_keys.indexOf(key) >= 0;
 }
-
-function format_object(obj) {
-    var lines = [];
-    var padding = "";
-    Object.keys(obj).map(function(name) {
-        if (padding.length < name.length) padding = Array(name.length + 1).join(" ");
-        return [ name, JSON.stringify(obj[name]) ];
-    }).forEach(function(tokens) {
-        lines.push("  " + tokens[0] + padding.slice(tokens[0].length - 2) + tokens[1]);
-    });
-    return lines.join("\n");
-}
-
-function print_error(msg) {
-    process.stderr.write(msg);
-    process.stderr.write("\n");
-}
-
-function print(txt) {
-    process.stdout.write(txt);
-    process.stdout.write("\n");
-}

lib/ast.js

@@ -157,7 +157,7 @@ var AST_SimpleStatement = DEFNODE("SimpleStatement", "body", {
 
 function walk_body(node, visitor) {
     var body = node.body;
-    if (body instanceof AST_Statement) {
+    if (body instanceof AST_Node) {
         body._walk(visitor);
     }
     else for (var i = 0, len = body.length; i < len; i++) {
@@ -284,6 +284,10 @@ var AST_ForIn = DEFNODE("ForIn", "init name object", {
     }
 }, AST_IterationStatement);
 
+var AST_ForOf = DEFNODE("ForOf", null, {
+    $documentation: "A `for ... of` statement",
+}, AST_ForIn);
+
 var AST_With = DEFNODE("With", "expression", {
     $documentation: "A `with` statement",
     $propdoc: {
@@ -311,6 +315,13 @@ var AST_Scope = DEFNODE("Scope", "directives variables functions uses_with uses_
         enclosed: "[SymbolDef*/S] a list of all symbol definitions that are accessed from this scope or any subscopes",
         cname: "[integer/S] current index for mangling variables (used internally by the mangler)",
     },
+    get_defun_scope: function () {
+        var self = this;
+        while (self.is_block_scope() && self.parent_scope) {
+            self = self.parent_scope;
+        }
+        return self;
+    }
 }, AST_Block);
 
 var AST_Toplevel = DEFNODE("Toplevel", "globals", {
@@ -331,13 +342,111 @@ var AST_Toplevel = DEFNODE("Toplevel", "globals", {
     }
 }, AST_Scope);
 
-var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments", {
+var AST_Expansion = DEFNODE("Expansion", "expression", {
+    $documentation: "An expandible argument, such as ...rest, a splat, such as [1,2,...all], or an expansion in a variable declaration, such as var [first, ...rest] = list",
+    $propdoc: {
+        expression: "AST_Symbol the thing to be expanded"
+    },
+    _walk: function(visitor) {
+        var self = this;
+        return visitor._visit(this, function(){
+            self.expression.walk(visitor);
+        });
+    }
+});
+
+var AST_ArrowParametersOrSeq = DEFNODE("ArrowParametersOrSeq", "expressions", {
+    $documentation: "A set of arrow function parameters or a sequence expression. This is used because when the parser sees a \"(\" it could be the start of a seq, or the start of a parameter list of an arrow function.",
+    $propdoc: {
+        expressions: "[AST_Expression|AST_Destructuring|AST_Expansion*] array of expressions or argument names or destructurings."
+    },
+    as_params: function (croak) {
+        // We don't want anything which doesn't belong in a destructuring
+        var root = this;
+        return this.expressions.map(function to_fun_args(ex, _, __, default_seen_above) {
+            var insert_default = function(ex, default_value) {
+                if (default_value) {
+                    return new AST_DefaultAssign({
+                        start: ex.start,
+                        left: ex,
+                        operator: "=",
+                        right: default_value,
+                        end: default_value.end
+                    });
+                }
+                return ex;
+            }
+            if (ex instanceof AST_Object) {
+                return insert_default(new AST_Destructuring({
+                    start: ex.start,
+                    end: ex.end,
+                    is_array: false,
+                    names: ex.properties.map(to_fun_args)
+                }), default_seen_above);
+            } else if (ex instanceof AST_ObjectKeyVal) {
+                if (ex.key instanceof AST_SymbolRef) {
+                    ex.key = to_fun_args(ex.key, 0, [ex.key]);
+                }
+                ex.value = to_fun_args(ex.value, 0, [ex.key]);
+                return insert_default(ex, default_seen_above);
+            } else if (ex instanceof AST_Hole) {
+                return ex;
+            } else if (ex instanceof AST_Destructuring) {
+                ex.names = ex.names.map(to_fun_args);
+                return insert_default(ex, default_seen_above);
+            } else if (ex instanceof AST_SymbolRef) {
+                return insert_default(new AST_SymbolFunarg({
+                    name: ex.name,
+                    start: ex.start,
+                    end: ex.end
+                }), default_seen_above);
+            } else if (ex instanceof AST_Expansion) {
+                ex.expression = to_fun_args(ex.expression);
+                return insert_default(ex, default_seen_above);
+            } else if (ex instanceof AST_Array) {
+                return insert_default(new AST_Destructuring({
+                    start: ex.start,
+                    end: ex.end,
+                    is_array: true,
+                    names: ex.elements.map(to_fun_args)
+                }), default_seen_above);
+            } else if (ex instanceof AST_Assign) {
+                return insert_default(to_fun_args(ex.left, undefined, undefined, ex.right), default_seen_above);
+            } else if (ex instanceof AST_DefaultAssign) {
+                ex.left = to_fun_args(ex.left, 0, [ex.left]);
+                return ex;
+            } else {
+                croak("Invalid function parameter", ex.start.line, ex.start.col);
+            }
+        });
+    },
+    as_expr: function() {
+        var exprs = this.expressions;
+        return exprs.length == 1 ? exprs[0] : new AST_Sequence({
+            expressions: exprs
+        });
+    }
+});
+
+var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments is_generator", {
     $documentation: "Base class for functions",
     $propdoc: {
+        is_generator: "[boolean] is generatorFn or not",
         name: "[AST_SymbolDeclaration?] the name of this function",
-        argnames: "[AST_SymbolFunarg*] array of function arguments",
+        argnames: "[AST_SymbolFunarg|AST_Destructuring|AST_Expansion|AST_DefaultAssign*] array of function arguments, destructurings, or expanding arguments",
         uses_arguments: "[boolean/S] tells whether this function accesses the arguments array"
     },
+    args_as_names: function () {
+        var out = [];
+        for (var i = 0; i < this.argnames.length; i++) {
+            if (this.argnames[i] instanceof AST_Destructuring) {
+                out = out.concat(this.argnames[i].all_symbols());
+            } else {
+                out.push(this.argnames[i]);
+            }
+        }
+        return out;
+    },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
             if (this.name) this.name._walk(visitor);
@@ -358,10 +467,78 @@ var AST_Function = DEFNODE("Function", null, {
     $documentation: "A function expression"
 }, AST_Lambda);
 
+var AST_Arrow = DEFNODE("Arrow", null, {
+    $documentation: "An ES6 Arrow function ((a) => b)"
+}, AST_Lambda);
+
 var AST_Defun = DEFNODE("Defun", null, {
     $documentation: "A function definition"
 }, AST_Lambda);
 
+/* -----[ DESTRUCTURING ]----- */
+var AST_Destructuring = DEFNODE("Destructuring", "names is_array", {
+    $documentation: "A destructuring of several names. Used in destructuring assignment and with destructuring function argument names",
+    $propdoc: {
+        "names": "[AST_Node*] Array of properties or elements",
+        "is_array": "[Boolean] Whether the destructuring represents an object or array"
+    },
+    _walk: function(visitor) {
+        return visitor._visit(this, function(){
+            this.names.forEach(function(name){
+                name._walk(visitor);
+            });
+        });
+    },
+    all_symbols: function() {
+        var out = [];
+        this.walk(new TreeWalker(function (node) {
+            if (node instanceof AST_Symbol) {
+                out.push(node);
+            }
+            if (node instanceof AST_Expansion) {
+                out.push(node.expression);
+            }
+        }));
+        return out;
+    }
+});
+
+var AST_PrefixedTemplateString = DEFNODE("PrefixedTemplateString", "template_string prefix", {
+    $documentation: "A templatestring with a prefix, such as String.raw`foobarbaz`",
+    $propdoc: {
+        template_string: "[AST_TemplateString] The template string",
+        prefix: "[AST_SymbolRef|AST_PropAccess] The prefix, which can be a symbol such as `foo` or a dotted expression such as `String.raw`."
+    },
+    _walk: function(visitor) {
+        this.prefix._walk(visitor);
+        this.template_string._walk(visitor);
+    }
+})
+
+var AST_TemplateString = DEFNODE("TemplateString", "segments", {
+    $documentation: "A template string literal",
+    $propdoc: {
+        segments: "[AST_TemplateSegment|AST_Expression]* One or more segments, starting with AST_TemplateSegment. AST_Expression may follow AST_TemplateSegment, but each AST_Expression must be followed by AST_TemplateSegment."
+    },
+    _walk: function(visitor) {
+        return visitor._visit(this, function(){
+            this.segments.forEach(function(seg, i){
+                if (i % 2 !== 0) {
+                    seg._walk(visitor);
+                }
+            });
+        });
+    }
+});
+
+var AST_TemplateSegment = DEFNODE("TemplateSegment", "value raw", {
+    $documentation: "A segment of a template string literal",
+    $propdoc: {
+        value: "Content of the segment",
+        raw: "Raw content of the segment"
+    }
+});
+
 /* -----[ JUMPS ]----- */
 
 var AST_Jump = DEFNODE("Jump", null, {
@@ -481,7 +658,7 @@ var AST_Try = DEFNODE("Try", "bcatch bfinally", {
 var AST_Catch = DEFNODE("Catch", "argname", {
     $documentation: "A `catch` node; only makes sense as part of a `try` statement",
     $propdoc: {
-        argname: "[AST_SymbolCatch] symbol for the exception"
+        argname: "[AST_SymbolCatch|AST_Destructuring|AST_Expansion|AST_DefaultAssign] symbol for the exception"
     },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
@@ -495,10 +672,10 @@ var AST_Finally = DEFNODE("Finally", null, {
     $documentation: "A `finally` node; only makes sense as part of a `try` statement"
 }, AST_Block);
 
-/* -----[ VAR ]----- */
+/* -----[ VAR/CONST ]----- */
 
 var AST_Definitions = DEFNODE("Definitions", "definitions", {
-    $documentation: "Base class for `var` nodes (variable declarations/initializations)",
+    $documentation: "Base class for `var` or `const` nodes (variable declarations/initializations)",
     $propdoc: {
         definitions: "[AST_VarDef*] array of variable definitions"
     },
@@ -516,10 +693,75 @@ var AST_Var = DEFNODE("Var", null, {
     $documentation: "A `var` statement"
 }, AST_Definitions);
 
+var AST_Let = DEFNODE("Let", null, {
+    $documentation: "A `let` statement"
+}, AST_Definitions);
+
+var AST_Const = DEFNODE("Const", null, {
+    $documentation: "A `const` statement"
+}, AST_Definitions);
+
+var AST_NameImport = DEFNODE("NameImport", "foreign_name name", {
+    $documentation: "The part of the import statement that imports names from a module.",
+    $propdoc: {
+        foreign_name: "[AST_SymbolImportForeign] The name being imported (as specified in the module)",
+        name: "[AST_SymbolImport] The name as it becomes available to this module."
+    },
+    _walk: function (visitor) {
+        return visitor._visit(this, function() {
+            this.foreign_name._walk(visitor);
+            this.name._walk(visitor);
+        });
+    }
+})
+
+var AST_Import = DEFNODE("Import", "imported_name imported_names module_name", {
+    $documentation: "An `import` statement",
+    $propdoc: {
+        imported_name: "[AST_SymbolImport] The name of the variable holding the module's default export.",
+        imported_names: "[AST_NameImport*] The names of non-default imported variables",
+        module_name: "[AST_String] String literal describing where this module came from",
+    },
+    _walk: function(visitor) {
+        return visitor._visit(this, function() {
+            if (this.imported_name) {
+                this.imported_name._walk(visitor);
+            }
+            if (this.imported_names) {
+                this.imported_names.forEach(function (name_import) {
+                    name_import._walk(visitor);
+                });
+            }
+            this.module_name._walk(visitor);
+        });
+    }
+});
+
+var AST_Export = DEFNODE("Export", "exported_definition exported_value is_default exported_names module_name", {
+    $documentation: "An `export` statement",
+    $propdoc: {
+        exported_definition: "[AST_Defun|AST_Definitions|AST_DefClass?] An exported definition",
+        exported_value: "[AST_Node?] An exported value",
+        exported_names: "[AST_NameImport*?] List of exported names",
+        module_name: "[AST_String?] Name of the file to load exports from",
+        is_default: "[Boolean] Whether this is the default exported value of this module"
+    },
+    _walk: function (visitor) {
+        visitor._visit(this, function () {
+            if (this.exported_definition) {
+                this.exported_definition._walk(visitor);
+            }
+            if (this.exported_value) {
+                this.exported_value._walk(visitor);
+            }
+        });
+    }
+}, AST_Statement);
+
 var AST_VarDef = DEFNODE("VarDef", "name value", {
     $documentation: "A variable declaration; only appears in a AST_Definitions node",
     $propdoc: {
-        name: "[AST_SymbolVar] name of the variable",
+        name: "[AST_SymbolVar|AST_SymbolConst|AST_Destructuring] name of the variable",
         value: "[AST_Node?] initializer, or null of there's no initializer"
     },
     _walk: function(visitor) {
@@ -650,6 +892,10 @@ var AST_Assign = DEFNODE("Assign", null, {
     $documentation: "An assignment expression — `a = b + 5`",
 }, AST_Binary);
 
+var AST_DefaultAssign = DEFNODE("DefaultAssign", null, {
+    $documentation: "A default assignment expression like in `(a = 3) => a`"
+}, AST_Binary);
+
 /* -----[ LITERALS ]----- */
 
 var AST_Array = DEFNODE("Array", "elements", {
@@ -685,11 +931,13 @@ var AST_Object = DEFNODE("Object", "properties", {
 var AST_ObjectProperty = DEFNODE("ObjectProperty", "key value", {
     $documentation: "Base class for literal object properties",
     $propdoc: {
-        key: "[string] the property name converted to a string for ObjectKeyVal.  For setters and getters this is an AST_SymbolAccessor.",
-        value: "[AST_Node] property value.  For setters and getters this is an AST_Accessor."
+        key: "[string|AST_Node] the property name converted to a string for ObjectKeyVal. For setters, getters and computed property this is an arbitrary AST_Node",
+        value: "[AST_Node] property value. For setters and getters this is an AST_Function."
     },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
+            if (this.key instanceof AST_Node)
+                this.key._walk(visitor);
             this.value._walk(visitor);
         });
     }
@@ -702,21 +950,72 @@ var AST_ObjectKeyVal = DEFNODE("ObjectKeyVal", "quote", {
     }
 }, AST_ObjectProperty);
 
-var AST_ObjectSetter = DEFNODE("ObjectSetter", null, {
+var AST_ObjectSetter = DEFNODE("ObjectSetter", "quote static", {
+    $propdoc: {
+        quote: "[string|undefined] the original quote character, if any",
+        static: "[boolean] whether this is a static setter (classes only)"
+    },
     $documentation: "An object setter property",
 }, AST_ObjectProperty);
 
-var AST_ObjectGetter = DEFNODE("ObjectGetter", null, {
+var AST_ObjectGetter = DEFNODE("ObjectGetter", "quote static", {
+    $propdoc: {
+        quote: "[string|undefined] the original quote character, if any",
+        static: "[boolean] whether this is a static getter (classes only)"
+    },
     $documentation: "An object getter property",
 }, AST_ObjectProperty);
 
+var AST_ConciseMethod = DEFNODE("ConciseMethod", "quote static is_generator", {
+    $propdoc: {
+        quote: "[string|undefined] the original quote character, if any",
+        static: "[boolean] whether this method is static (classes only)",
+        is_generator: "[boolean] is generatorFn or not",
+    },
+    $documentation: "An ES6 concise method inside an object or class"
+}, AST_ObjectProperty);
+
+var AST_Class = DEFNODE("Class", "name extends properties", {
+    $propdoc: {
+        name: "[AST_SymbolClass|AST_SymbolDefClass?] optional class name.",
+        extends: "[AST_Node]? optional parent class",
+        properties: "[AST_ObjectProperty*] array of properties"
+    },
+    $documentation: "An ES6 class",
+    _walk: function(visitor) {
+        return visitor._visit(this, function(){
+            if (this.name) {
+                this.name._walk(visitor);
+            }
+            if (this.extends) {
+                this.extends._walk(visitor);
+            }
+            this.properties.forEach(function(prop){
+                prop._walk(visitor);
+            });
+        });
+    },
+}, AST_Scope);
+
+var AST_DefClass = DEFNODE("DefClass", null, {
+    $documentation: "A class definition",
+}, AST_Class);
+
+var AST_ClassExpression = DEFNODE("ClassExpression", null, {
+    $documentation: "A class expression."
+}, AST_Class);
+
 var AST_Symbol = DEFNODE("Symbol", "scope name thedef", {
     $propdoc: {
         name: "[string] name of this symbol",
         scope: "[AST_Scope/S] the current scope (not necessarily the definition scope)",
         thedef: "[SymbolDef/S] the definition of this symbol"
     },
-    $documentation: "Base class for all symbols",
+    $documentation: "Base class for all symbols"
+});
+
+var AST_NewTarget = DEFNODE("NewTarget", null, {
+    $documentation: "A reference to new.target"
 });
 
 var AST_SymbolAccessor = DEFNODE("SymbolAccessor", null, {
@@ -724,13 +1023,25 @@ var AST_SymbolAccessor = DEFNODE("SymbolAccessor", null, {
 }, AST_Symbol);
 
 var AST_SymbolDeclaration = DEFNODE("SymbolDeclaration", "init", {
-    $documentation: "A declaration symbol (symbol in var, function name or argument, symbol in catch)",
+    $documentation: "A declaration symbol (symbol in var/const, function name or argument, symbol in catch)",
 }, AST_Symbol);
 
 var AST_SymbolVar = DEFNODE("SymbolVar", null, {
     $documentation: "Symbol defining a variable",
 }, AST_SymbolDeclaration);
 
+var AST_SymbolBlockDeclaration = DEFNODE("SymbolBlockDeclaration", null, {
+    $documentation: "Base class for block-scoped declaration symbols"
+}, AST_SymbolDeclaration);
+
+var AST_SymbolConst = DEFNODE("SymbolConst", null, {
+    $documentation: "A constant declaration"
+}, AST_SymbolBlockDeclaration);
+
+var AST_SymbolLet = DEFNODE("SymbolLet", null, {
+    $documentation: "A block-scoped `let` declaration"
+}, AST_SymbolBlockDeclaration);
+
 var AST_SymbolFunarg = DEFNODE("SymbolFunarg", null, {
     $documentation: "Symbol naming a function argument",
 }, AST_SymbolVar);
@@ -739,13 +1050,33 @@ var AST_SymbolDefun = DEFNODE("SymbolDefun", null, {
     $documentation: "Symbol defining a function",
 }, AST_SymbolDeclaration);
 
+var AST_SymbolMethod = DEFNODE("SymbolMethod", null, {
+    $documentation: "Symbol in an object defining a method",
+}, AST_Symbol);
+
 var AST_SymbolLambda = DEFNODE("SymbolLambda", null, {
     $documentation: "Symbol naming a function expression",
 }, AST_SymbolDeclaration);
 
+var AST_SymbolDefClass = DEFNODE("SymbolDefClass", null, {
+    $documentation: "Symbol naming a class's name in a class declaration. Lexically scoped to its containing scope, and accessible within the class."
+}, AST_SymbolBlockDeclaration);
+
+var AST_SymbolClass = DEFNODE("SymbolClass", null, {
+    $documentation: "Symbol naming a class's name. Lexically scoped to the class."
+}, AST_SymbolDeclaration);
+
 var AST_SymbolCatch = DEFNODE("SymbolCatch", null, {
     $documentation: "Symbol naming the exception in catch",
-}, AST_SymbolDeclaration);
+}, AST_SymbolBlockDeclaration);
+
+var AST_SymbolImport = DEFNODE("SymbolImport", null, {
+    $documentation: "Symbol refering to an imported name",
+}, AST_SymbolBlockDeclaration);
+
+var AST_SymbolImportForeign = DEFNODE("SymbolImportForeign", null, {
+    $documentation: "A symbol imported from a module, but it is defined in the other module, and its real name is irrelevant for this module's purposes",
+}, AST_Symbol);
 
 var AST_Label = DEFNODE("Label", "references", {
     $documentation: "Symbol naming a label (declaration)",
@@ -770,6 +1101,10 @@ var AST_This = DEFNODE("This", null, {
     $documentation: "The `this` symbol",
 }, AST_Symbol);
 
+var AST_Super = DEFNODE("Super", null, {
+    $documentation: "The `super` symbol",
+}, AST_Symbol);
+
 var AST_Constant = DEFNODE("Constant", null, {
     $documentation: "Base class for all constants",
     getValue: function() {
@@ -843,6 +1178,21 @@ var AST_True = DEFNODE("True", null, {
     value: true
 }, AST_Boolean);
 
+/* -----[ Yield ]----- */
+
+var AST_Yield = DEFNODE("Yield", "expression is_star", {
+    $documentation: "A `yield` statement",
+    $propdoc: {
+        expression: "[AST_Node?] the value returned or thrown by this statement; could be null (representing undefined) but only when is_star is set to false",
+        is_star: "[Boolean] Whether this is a yield or yield* statement"
+    },
+    _walk: function(visitor) {
+        return visitor._visit(this, this.expression && function(){
+            this.expression._walk(visitor);
+        });
+    }
+});
+
 /* -----[ TreeWalker ]----- */
 
 function TreeWalker(callback) {
@@ -870,12 +1220,17 @@ TreeWalker.prototype = {
             this.directives = Object.create(this.directives);
         } else if (node instanceof AST_Directive && !this.directives[node.value]) {
             this.directives[node.value] = node;
+        } else if (node instanceof AST_Class) {
+            this.directives = Object.create(this.directives);
+            if (!this.directives["use strict"]) {
+                this.directives["use strict"] = node;
+            }
         }
         this.stack.push(node);
     },
     pop: function(node) {
         this.stack.pop();
-        if (node instanceof AST_Lambda) {
+        if (node instanceof AST_Lambda || node instanceof AST_Class) {
             this.directives = Object.getPrototypeOf(this.directives);
         }
     },
@@ -893,7 +1248,7 @@ TreeWalker.prototype = {
         var dir = this.directives[type];
         if (dir) return dir;
         var node = this.stack[this.stack.length - 1];
-        if (node instanceof AST_Scope) {
+        if (node instanceof AST_Scope && node.body) {
             for (var i = 0; i < node.body.length; ++i) {
                 var st = node.body[i];
                 if (!(st instanceof AST_Directive)) break;

lib/minify.js

@@ -30,6 +30,9 @@ function set_shorthand(name, options, keys) {
 function minify(files, options) {
     var warn_function = AST_Node.warn_function;
     try {
+        if (typeof files == "string") {
+            files = [ files ];
+        }
         options = defaults(options, {
             compress: {},
             ie8: false,
@@ -38,14 +41,10 @@ function minify(files, options) {
             output: {},
             parse: {},
             sourceMap: false,
-            timings: false,
             toplevel: false,
             warnings: false,
             wrap: false,
         }, true);
-        var timings = options.timings && {
-            start: Date.now()
-        };
         set_shorthand("ie8", options, [ "compress", "mangle", "output" ]);
         set_shorthand("keep_fnames", options, [ "compress", "mangle" ]);
         set_shorthand("toplevel", options, [ "compress", "mangle" ]);
@@ -58,6 +57,7 @@ function minify(files, options) {
                 keep_fnames: false,
                 properties: false,
                 reserved: [],
+                safari10: false,
                 toplevel: false,
             }, true);
         }
@@ -76,17 +76,13 @@ function minify(files, options) {
                 warnings.push(warning);
             };
         }
-        if (timings) timings.parse = Date.now();
         var toplevel;
         if (files instanceof AST_Toplevel) {
             toplevel = files;
         } else {
-            if (typeof files == "string") {
-                files = [ files ];
-            }
             options.parse = options.parse || {};
             options.parse.toplevel = null;
-            for (var name in files) if (HOP(files, name)) {
+            for (var name in files) {
                 options.parse.filename = name;
                 options.parse.toplevel = parse(files[name], options.parse);
                 if (options.sourceMap && options.sourceMap.content == "inline") {
@@ -100,23 +96,19 @@ function minify(files, options) {
         if (options.wrap) {
             toplevel = toplevel.wrap_commonjs(options.wrap);
         }
-        if (timings) timings.scope1 = Date.now();
-        if (options.compress) toplevel.figure_out_scope(options.mangle);
-        if (timings) timings.compress = Date.now();
-        if (options.compress) toplevel = new Compressor(options.compress).compress(toplevel);
-        if (timings) timings.scope2 = Date.now();
-        if (options.mangle) toplevel.figure_out_scope(options.mangle);
-        if (timings) timings.mangle = Date.now();
+        if (options.compress) {
+            toplevel.figure_out_scope(options.mangle);
+            toplevel = new Compressor(options.compress).compress(toplevel);
+        }
         if (options.mangle) {
+            toplevel.figure_out_scope(options.mangle);
             base54.reset();
             toplevel.compute_char_frequency(options.mangle);
             toplevel.mangle_names(options.mangle);
+            if (options.mangle.properties) {
+                toplevel = mangle_properties(toplevel, options.mangle.properties);
+            }
         }
-        if (timings) timings.properties = Date.now();
-        if (options.mangle && options.mangle.properties) {
-            toplevel = mangle_properties(toplevel, options.mangle.properties);
-        }
-        if (timings) timings.output = Date.now();
         var result = {};
         if (options.output.ast) {
             result.ast = toplevel;
@@ -132,9 +124,7 @@ function minify(files, options) {
                     root: options.sourceMap.root
                 });
                 if (options.sourceMap.includeSources) {
-                    if (files instanceof AST_Toplevel) {
-                        throw new Error("original source content unavailable");
-                    } else for (var name in files) if (HOP(files, name)) {
+                    for (var name in files) {
                         options.output.source_map.get().setSourceContent(name, files[name]);
                     }
                 }
@@ -153,18 +143,6 @@ function minify(files, options) {
                 }
             }
         }
-        if (timings) {
-            timings.end = Date.now();
-            result.timings = {
-                parse: 1e-3 * (timings.scope1 - timings.parse),
-                scope: 1e-3 * (timings.compress - timings.scope1 + timings.mangle - timings.scope2),
-                compress: 1e-3 * (timings.scope2 - timings.compress),
-                mangle: 1e-3 * (timings.properties - timings.mangle),
-                properties: 1e-3 * (timings.output - timings.properties),
-                output: 1e-3 * (timings.end - timings.output),
-                total: 1e-3 * (timings.end - timings.start)
-            }
-        }
         if (warnings.length) {
             result.warnings = warnings;
         }

lib/mozilla-ast.js

@@ -111,19 +111,23 @@
         },
         Property: function(M) {
             var key = M.key;
+            var name = key.type == "Identifier" ? key.name : key.value;
             var args = {
                 start    : my_start_token(key),
                 end      : my_end_token(M.value),
-                key      : key.type == "Identifier" ? key.name : key.value,
+                key      : name,
                 value    : from_moz(M.value)
             };
-            if (M.kind == "init") return new AST_ObjectKeyVal(args);
-            args.key = new AST_SymbolAccessor({
-                name: args.key
-            });
-            args.value = new AST_Accessor(args.value);
-            if (M.kind == "get") return new AST_ObjectGetter(args);
-            if (M.kind == "set") return new AST_ObjectSetter(args);
+            switch (M.kind) {
+              case "init":
+                return new AST_ObjectKeyVal(args);
+              case "set":
+                args.value.name = from_moz(key);
+                return new AST_ObjectSetter(args);
+              case "get":
+                args.value.name = from_moz(key);
+                return new AST_ObjectGetter(args);
+            }
         },
         ArrayExpression: function(M) {
             return new AST_Array({
@@ -168,7 +172,7 @@
             });
         },
         VariableDeclaration: function(M) {
-            return new AST_Var({
+            return new (M.kind === "const" ? AST_Const : AST_Var)({
                 start       : my_start_token(M),
                 end         : my_end_token(M),
                 definitions : M.declarations.map(from_moz)
@@ -204,7 +208,7 @@
         Identifier: function(M) {
             var p = FROM_MOZ_STACK[FROM_MOZ_STACK.length - 2];
             return new (  p.type == "LabeledStatement" ? AST_Label
-                        : p.type == "VariableDeclarator" && p.id === M ? AST_SymbolVar
+                        : p.type == "VariableDeclarator" && p.id === M ? (p.kind == "const" ? AST_SymbolConst : AST_SymbolVar)
                         : p.type == "FunctionExpression" ? (p.id === M ? AST_SymbolLambda : AST_SymbolFunarg)
                         : p.type == "FunctionDeclaration" ? (p.id === M ? AST_SymbolDefun : AST_SymbolFunarg)
                         : p.type == "CatchClause" ? AST_SymbolCatch
@@ -256,7 +260,10 @@
     map("CallExpression", AST_Call, "callee>expression, arguments@args");
 
     def_to_moz(AST_Toplevel, function To_Moz_Program(M) {
-        return to_moz_scope("Program", M);
+        return {
+            type: "Program",
+            body: M.body.map(to_moz)
+        };
     });
 
     def_to_moz(AST_Defun, function To_Moz_FunctionDeclaration(M) {
@@ -264,7 +271,7 @@
             type: "FunctionDeclaration",
             id: to_moz(M.name),
             params: M.argnames.map(to_moz),
-            body: to_moz_scope("BlockStatement", M)
+            body: to_moz_block(M)
         }
     });
 
@@ -273,7 +280,7 @@
             type: "FunctionExpression",
             id: to_moz(M.name),
             params: M.argnames.map(to_moz),
-            body: to_moz_scope("BlockStatement", M)
+            body: to_moz_block(M)
         }
     });
 
@@ -324,7 +331,7 @@
     def_to_moz(AST_Definitions, function To_Moz_VariableDeclaration(M) {
         return {
             type: "VariableDeclaration",
-            kind: "var",
+            kind: M instanceof AST_Const ? "const" : "var",
             declarations: M.definitions.map(to_moz)
         };
     });
@@ -379,10 +386,11 @@
     });
 
     def_to_moz(AST_ObjectProperty, function To_Moz_Property(M) {
-        var key = {
-            type: "Literal",
-            value: M.key instanceof AST_SymbolAccessor ? M.key.name : M.key
-        };
+        var key = (
+            is_identifier(M.key)
+            ? {type: "Identifier", name: M.key}
+            : {type: "Literal", value: M.key}
+        );
         var kind;
         if (M instanceof AST_ObjectKeyVal) {
             kind = "init";
@@ -543,8 +551,8 @@
         moz_to_me = new Function("U2", "my_start_token", "my_end_token", "from_moz", "return(" + moz_to_me + ")")(
             exports, my_start_token, my_end_token, from_moz
         );
-        me_to_moz = new Function("to_moz", "to_moz_block", "to_moz_scope", "return(" + me_to_moz + ")")(
-            to_moz, to_moz_block, to_moz_scope
+        me_to_moz = new Function("to_moz", "to_moz_block", "return(" + me_to_moz + ")")(
+            to_moz, to_moz_block
         );
         MOZ_TO_ME[moztype] = moz_to_me;
         def_to_moz(mytype, me_to_moz);
@@ -602,14 +610,4 @@
         };
     };
 
-    function to_moz_scope(type, node) {
-        var body = node.body.map(to_moz);
-        if (node.body[0] instanceof AST_SimpleStatement && node.body[0].body instanceof AST_String) {
-            body.unshift(to_moz(new AST_EmptyStatement(node.body[0])));
-        }
-        return {
-            type: type,
-            body: body
-        };
-    };
 })();

lib/output.js

@@ -54,9 +54,11 @@ function OutputStream(options) {
 
     options = defaults(options, {
         ascii_only       : false,
+        ascii_identifiers: undefined,
         beautify         : false,
         bracketize       : false,
         comments         : false,
+        ecma             : 5,
         ie8              : false,
         indent_level     : 4,
         indent_start     : 0,
@@ -69,12 +71,20 @@ function OutputStream(options) {
         quote_style      : 0,
         semicolons       : true,
         shebang          : true,
+        shorthand        : undefined,
         source_map       : null,
-        webkit           : false,
+        space_colon      : true,
+        unescape_regexps : false,
         width            : 80,
         wrap_iife        : false,
     }, true);
 
+    if (typeof options.ascii_identifiers === 'undefined')
+        options.ascii_identifiers = options.ascii_only;
+
+    if (options.shorthand === undefined)
+        options.shorthand = options.ecma > 5;
+
     // 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) {
@@ -110,9 +120,19 @@ function OutputStream(options) {
     var OUTPUT = "";
 
     function to_ascii(str, identifier) {
-        return str.replace(/[\u0000-\u001f\u007f-\uffff]/g, function(ch) {
-            var code = ch.charCodeAt(0).toString(16);
-            if (code.length <= 2 && !identifier) {
+        return str.replace(/[\ud800-\udbff][\udc00-\udfff]|[\u0000-\u001f\u007f-\uffff]/g, function(ch) {
+            var code = get_full_char_code(ch, 0).toString(16);
+
+            if ((identifier && code.length === 1 && options.ecma >= 6) || code.length > 4) {
+                if (options.ecma < 6) {
+                    if (identifier) {
+                        return ch; // no \u{} support
+                    }
+                    return "\\u" + ch.charCodeAt(0).toString(16) + "\\u"
+                        + ch.charCodeAt(1).toString(16);
+                }
+                return "\\u{" + code + "}";
+            } else if (code.length <= 2 && !identifier) {
                 while (code.length < 2) code = "0" + code;
                 return "\\x" + code;
             } else {
@@ -140,7 +160,7 @@ function OutputStream(options) {
               case "\u2029": return "\\u2029";
               case "\ufeff": return "\\ufeff";
               case "\0":
-                  return /[0-7]/.test(str.charAt(i+1)) ? "\\x00" : "\\0";
+                  return /[0-7]/.test(get_full_char(str, i+1)) ? "\\x00" : "\\0";
             }
             return s;
         });
@@ -150,7 +170,11 @@ function OutputStream(options) {
         function quote_double() {
             return '"' + str.replace(/\x22/g, '\\"') + '"';
         }
+        function quote_template() {
+            return '`' + str.replace(/`/g, '\\`') + '`';
+        }
         if (options.ascii_only) str = to_ascii(str);
+        if (quote === "`") return quote_template();
         switch (options.quote_style) {
           case 1:
             return quote_single();
@@ -175,7 +199,7 @@ function OutputStream(options) {
 
     function make_name(name) {
         name = name.toString();
-        if (options.ascii_only)
+        if (options.ascii_identifiers)
             name = to_ascii(name, true);
         return name;
     };
@@ -190,43 +214,12 @@ function OutputStream(options) {
     var might_need_semicolon = false;
     var might_add_newline = 0;
     var last = "";
-    var mapping_token, mapping_name, mappings = options.source_map && [];
-
-    var do_add_mapping = mappings ? function() {
-        mappings.forEach(function(mapping) {
-            try {
-                options.source_map.add(
-                    mapping.token.file,
-                    mapping.line, mapping.col,
-                    mapping.token.line, mapping.token.col,
-                    !mapping.name && mapping.token.type == "name" ? mapping.token.value : mapping.name
-                );
-            } catch(ex) {
-                AST_Node.warn("Couldn't figure out mapping for {file}:{line},{col} → {cline},{ccol} [{name}]", {
-                    file: mapping.token.file,
-                    line: mapping.token.line,
-                    col: mapping.token.col,
-                    cline: mapping.line,
-                    ccol: mapping.col,
-                    name: mapping.name || ""
-                })
-            }
-        });
-        mappings = [];
-    } : noop;
 
     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);
-                if (mappings) {
-                    var delta = right.length - current_col;
-                    mappings.forEach(function(mapping) {
-                        mapping.line++;
-                        mapping.col += delta;
-                    });
-                }
                 OUTPUT = left + "\n" + right;
                 current_line++;
                 current_pos++;
@@ -236,18 +229,15 @@ function OutputStream(options) {
                 AST_Node.warn("Output exceeds {max_line_len} characters", options);
             }
         }
-        if (might_add_newline) {
-            might_add_newline = 0;
-            do_add_mapping();
-        }
+        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);
+        var ch = get_full_char(str, 0);
+        var prev = get_full_char(last, last.length - 1);
         if (might_need_semicolon) {
             might_need_semicolon = false;
 
@@ -299,18 +289,6 @@ function OutputStream(options) {
             }
             might_need_space = false;
         }
-
-        if (mapping_token) {
-            mappings.push({
-                token: mapping_token,
-                name: mapping_name,
-                line: current_line,
-                col: current_col
-            });
-            mapping_token = false;
-            if (!might_add_newline) do_add_mapping();
-        }
-
         OUTPUT += str;
         current_pos += str.length;
         var a = str.split(/\r?\n/), n = a.length - 1;
@@ -323,6 +301,10 @@ function OutputStream(options) {
         last = str;
     };
 
+    var star = function(){
+        print("*");
+    }
+
     var space = options.beautify ? function() {
         print(" ");
     } : function() {
@@ -402,12 +384,27 @@ function OutputStream(options) {
 
     function colon() {
         print(":");
-        space();
+        if (options.space_colon) space();
     };
 
-    var add_mapping = mappings ? function(token, name) {
-        mapping_token = token;
-        mapping_name = name;
+    var add_mapping = options.source_map ? function(token, name) {
+        try {
+            if (token) options.source_map.add(
+                token.file || "?",
+                current_line, current_col,
+                token.line, token.col,
+                (!name && token.type == "name") ? token.value : name
+            );
+        } catch(ex) {
+            AST_Node.warn("Couldn't figure out mapping for {file}:{line},{col} → {cline},{ccol} [{name}]", {
+                file: token.file,
+                line: token.line,
+                col: token.col,
+                cline: current_line,
+                ccol: current_col,
+                name: name || ""
+            })
+        }
     } : noop;
 
     function get() {
@@ -427,6 +424,7 @@ function OutputStream(options) {
         should_break    : function() { return options.width && this.current_width() >= options.width },
         newline         : newline,
         print           : print,
+        star            : star,
         space           : space,
         comma           : comma,
         colon           : colon,
@@ -446,6 +444,10 @@ function OutputStream(options) {
             }
             print(encoded);
         },
+        print_template_string_chars: function(str) {
+            var encoded = encode_string(str, '`').replace(/\${/g, "\\${");
+            return print(encoded.substr(1, encoded.length - 2));
+        },
         encode_string   : encode_string,
         next_indent     : next_indent,
         with_indent     : with_indent,
@@ -598,13 +600,6 @@ function OutputStream(options) {
             return true;
         }
 
-        if (output.option('webkit')) {
-            var p = output.parent();
-            if (p instanceof AST_PropAccess && p.expression === this) {
-                return true;
-            }
-        }
-
         if (output.option('wrap_iife')) {
             var p = output.parent();
             return p instanceof AST_Call && p.expression === this;
@@ -613,6 +608,11 @@ function OutputStream(options) {
         return false;
     });
 
+    PARENS(AST_Arrow, function(output){
+        var p = output.parent();
+        return p instanceof AST_PropAccess && p.expression === this;
+    });
+
     // same goes for an object literal, because otherwise it would be
     // interpreted as a block of code.
     PARENS(AST_Object, function(output){
@@ -622,20 +622,29 @@ function OutputStream(options) {
     PARENS(AST_Unary, function(output){
         var p = output.parent();
         return p instanceof AST_PropAccess && p.expression === this
-            || p instanceof AST_Call && p.expression === this;
+            || p instanceof AST_Call && p.expression === this
+            || p instanceof AST_Binary
+                && p.operator === "**"
+                && this instanceof AST_UnaryPrefix
+                && p.left === this
+                && this.operator !== "++"
+                && this.operator !== "--";
     });
 
     PARENS(AST_Sequence, function(output){
         var p = output.parent();
-        return p instanceof AST_Call             // (foo, bar)() or foo(1, (2, 3), 4)
-            || p instanceof AST_Unary            // !(foo, bar, baz)
-            || p instanceof AST_Binary           // 1 + (2, 3) + 4 ==> 8
-            || p instanceof AST_VarDef           // var a = (1, 2), b = a + a; ==> b == 4
-            || p instanceof AST_PropAccess       // (1, {foo:2}).foo or (1, {foo:2})["foo"] ==> 2
-            || p instanceof AST_Array            // [ 1, (2, 3), 4 ] ==> [ 1, 3, 4 ]
-            || p instanceof AST_ObjectProperty   // { foo: (1, 2) }.foo ==> 2
-            || p instanceof AST_Conditional      /* (false, true) ? (a = 10, b = 20) : (c = 30)
-                                                  * ==> 20 (side effect, set a := 10 and b := 20) */
+        return p instanceof AST_Call                          // (foo, bar)() or foo(1, (2, 3), 4)
+            || p instanceof AST_Unary                         // !(foo, bar, baz)
+            || p instanceof AST_Binary                        // 1 + (2, 3) + 4 ==> 8
+            || p instanceof AST_VarDef                        // var a = (1, 2), b = a + a; ==> b == 4
+            || p instanceof AST_PropAccess                    // (1, {foo:2}).foo or (1, {foo:2})["foo"] ==> 2
+            || p instanceof AST_Array                         // [ 1, (2, 3), 4 ] ==> [ 1, 3, 4 ]
+            || p instanceof AST_ObjectProperty                // { foo: (1, 2) }.foo ==> 2
+            || p instanceof AST_Conditional                   /* (false, true) ? (a = 10, b = 20) : (c = 30)
+                                                               * ==> 20 (side effect, set a := 10 and b := 20) */
+            || p instanceof AST_Arrow                         // x => (x, x)
+            || p instanceof AST_DefaultAssign                 // x => (x = (0, function(){}))
+            || (p instanceof AST_Class && p.extends === this) // class D extends (calls++, C) {}
         ;
     });
 
@@ -662,6 +671,24 @@ function OutputStream(options) {
         }
     });
 
+    PARENS(AST_Yield, function(output){
+        var p = output.parent();
+        // (yield 1) + (yield 2)
+        // a = yield 3
+        if (p instanceof AST_Binary && p.operator !== "=")
+            return true;
+        // (yield 1) ? yield 2 : yield 3
+        if (p instanceof AST_Conditional && p.condition === this)
+            return true;
+        // -(yield 4)
+        if (p instanceof AST_Unary)
+            return true;
+        // (yield x).foo
+        // (yield x)['foo']
+        if (p instanceof AST_PropAccess && p.expression === this)
+            return true;
+    });
+
     PARENS(AST_PropAccess, function(output){
         var p = output.parent();
         if (p instanceof AST_New && p.expression === this) {
@@ -731,6 +758,9 @@ function OutputStream(options) {
         // (a = foo)["prop"] —or— (a = foo).prop
         if (p instanceof AST_PropAccess && p.expression === this)
             return true;
+        // ({a, b} = {a: 1, b: 2}), a destructuring assignment
+        if (this instanceof AST_Assign && this.left instanceof AST_Destructuring && this.left.is_array === false)
+            return true;
     });
 
     /* -----[ PRINTERS ]----- */
@@ -739,6 +769,28 @@ function OutputStream(options) {
         output.print_string(self.value, self.quote);
         output.semicolon();
     });
+
+    DEFPRINT(AST_Expansion, function (self, output) {
+        output.print('...');
+        self.expression.print(output);
+    });
+
+    DEFPRINT(AST_Destructuring, function (self, output) {
+        output.print(self.is_array ? "[" : "{");
+        var first = true;
+        var len = self.names.length;
+        self.names.forEach(function (name, i) {
+            if (first) first = false; else { output.comma(); output.space(); }
+            name.print(output);
+            // If the final element is a hole, we need to make sure it
+            // doesn't look like a trailing comma, by inserting an actual
+            // trailing comma.
+            if (i === len - 1 && name instanceof AST_Hole)
+              output.comma();
+        })
+        output.print(self.is_array ? "]" : "}");
+    });
+
     DEFPRINT(AST_Debugger, function(self, output){
         output.print("debugger");
         output.semicolon();
@@ -863,7 +915,11 @@ function OutputStream(options) {
         output.with_parens(function(){
             self.init.print(output);
             output.space();
-            output.print("in");
+            if (self instanceof AST_ForOf) {
+                output.print("of");
+            } else {
+                output.print("in");
+            }
             output.space();
             self.object.print(output);
         });
@@ -885,10 +941,19 @@ function OutputStream(options) {
         var self = this;
         if (!nokeyword) {
             output.print("function");
+            if (this.is_generator) {
+                output.star();
+            }
+            if (self.name) {
+                output.space();
+            }
         }
-        if (self.name) {
-            output.space();
+        if (self.name instanceof AST_Symbol) {
             self.name.print(output);
+        } else if (nokeyword && self.name instanceof AST_Node) {
+            output.with_square(function() {
+                self.name.print(output); // Computed method name
+            });
         }
         output.with_parens(function(){
             self.argnames.forEach(function(arg, i){
@@ -903,6 +968,56 @@ function OutputStream(options) {
         self._do_print(output);
     });
 
+    DEFPRINT(AST_PrefixedTemplateString, function(self, output) {
+        self.prefix.print(output);
+        self.template_string.print(output);
+    });
+    DEFPRINT(AST_TemplateString, function(self, output) {
+        var is_tagged = output.parent() instanceof AST_PrefixedTemplateString;
+
+        output.print("`");
+        for (var i = 0; i < self.segments.length; i++) {
+            if (!(self.segments[i] instanceof AST_TemplateSegment)) {
+                output.print("${");
+                self.segments[i].print(output);
+                output.print("}");
+            } else if (is_tagged) {
+                output.print(self.segments[i].raw);
+            } else {
+                output.print_template_string_chars(self.segments[i].value);
+            }
+        }
+        output.print("`");
+    });
+
+    AST_Arrow.DEFMETHOD("_do_print", function(output){
+        var self = this;
+        var parent = output.parent();
+        var needs_parens = parent instanceof AST_Binary ||
+            parent instanceof AST_Unary ||
+            (parent instanceof AST_Call && self === parent.expression);
+        if (needs_parens) { output.print("(") }
+        if (self.argnames.length === 1 && self.argnames[0] instanceof AST_Symbol) {
+            self.argnames[0].print(output);
+        } else {
+            output.with_parens(function(){
+                self.argnames.forEach(function(arg, i){
+                    if (i) output.comma();
+                    arg.print(output);
+                });
+            });
+        }
+        output.space();
+        output.print('=>');
+        output.space();
+        if (self.body instanceof AST_Node) {
+            this.body.print(output);
+        } else {
+            print_bracketed(this.body, output);
+        }
+        if (needs_parens) { output.print(")") }
+    });
+
     /* -----[ exits ]----- */
     AST_Exit.DEFMETHOD("_do_print", function(output, kind){
         output.print(kind);
@@ -919,6 +1034,17 @@ function OutputStream(options) {
         self._do_print(output, "throw");
     });
 
+    /* -----[ yield ]----- */
+
+    DEFPRINT(AST_Yield, function(self, output){
+        var star = self.is_star ? "*" : "";
+        output.print("yield" + star);
+        if (self.expression) {
+            output.space();
+            self.expression.print(output);
+        }
+    });
+
     /* -----[ loop control ]----- */
     AST_LoopControl.DEFMETHOD("_do_print", function(output, kind){
         output.print(kind);
@@ -1067,9 +1193,107 @@ function OutputStream(options) {
         if (!avoid_semicolon)
             output.semicolon();
     });
+    DEFPRINT(AST_Let, function(self, output){
+        self._do_print(output, "let");
+    });
     DEFPRINT(AST_Var, function(self, output){
         self._do_print(output, "var");
     });
+    DEFPRINT(AST_Const, function(self, output){
+        self._do_print(output, "const");
+    });
+    DEFPRINT(AST_Import, function(self, output) {
+        output.print("import");
+        output.space();
+        if (self.imported_name) {
+            self.imported_name.print(output);
+        }
+        if (self.imported_name && self.imported_names) {
+            output.print(",");
+            output.space();
+        }
+        if (self.imported_names) {
+            if (self.imported_names.length === 1 && self.imported_names[0].foreign_name.name === "*") {
+                self.imported_names[0].print(output);
+            } else {
+                output.print("{");
+                self.imported_names.forEach(function (name_import, i) {
+                    output.space();
+                    name_import.print(output);
+                    if (i < self.imported_names.length - 1) {
+                        output.print(",");
+                        output.space();
+                    }
+                });
+                output.space();
+                output.print("}");
+            }
+        }
+        if (self.imported_name || self.imported_names) {
+            output.space();
+            output.print("from")
+            output.space();
+        }
+        self.module_name.print(output);
+        output.semicolon();
+    });
+
+    DEFPRINT(AST_NameImport, function(self, output) {
+        var definition = self.name.definition();
+        var names_are_different =
+            (definition && definition.mangled_name || self.name.name) !==
+            self.foreign_name.name;
+        if (names_are_different) {
+            output.print(self.foreign_name.name);
+            output.space();
+            output.print("as");
+            output.space();
+            self.name.print(output);
+        } else {
+            self.name.print(output);
+        }
+    });
+
+    DEFPRINT(AST_Export, function(self, output) {
+        output.print("export");
+        output.space();
+        if (self.is_default) {
+            output.print("default");
+            output.space();
+        }
+        if (self.exported_names) {
+            output.space();
+
+            if (self.exported_names.length === 1 && self.exported_names[0].name.name === "*") {
+                self.exported_names[0].print(output);
+            } else {
+                output.print("{");
+                self.exported_names.forEach(function (name_import, i) {
+                    output.space();
+                    name_import.print(output);
+                    if (i < self.exported_names.length - 1) {
+                        output.print(",");
+                        output.space();
+                    }
+                });
+                output.space();
+                output.print("}");
+            }
+            output.space();
+        }
+        else if (self.exported_value) {
+            self.exported_value.print(output);
+        } else if (self.exported_definition) {
+            self.exported_definition.print(output);
+        }
+        if (self.module_name) {
+            output.space();
+            output.print("from");
+            output.space();
+            self.module_name.print(output);
+        }
+        output.semicolon();
+    });
 
     function parenthesize_for_noin(node, output, noin) {
         if (!noin) node.print(output);
@@ -1242,8 +1466,35 @@ function OutputStream(options) {
         });
         else output.print("{}");
     });
-
-    function print_property_name(key, quote, output) {
+    DEFPRINT(AST_Class, function(self, output){
+        output.print("class");
+        output.space();
+        if (self.name) {
+            self.name.print(output);
+            output.space();
+        }
+        if (self.extends) {
+            output.print("extends");
+            output.space();
+            self.extends.print(output);
+            output.space();
+        }
+        if (self.properties.length > 0) output.with_block(function(){
+            self.properties.forEach(function(prop, i){
+                if (i) {
+                    output.newline();
+                }
+                output.indent();
+                prop.print(output);
+            });
+            output.newline();
+        });
+        else output.print("{}");
+    });
+    DEFPRINT(AST_NewTarget, function(self, output) {
+        output.print("new.target");
+    });
+    AST_ObjectProperty.DEFMETHOD("print_property_name", function(key, quote, output) {
         if (output.option("quote_keys")) {
             output.print_string(key + "");
         } else if ((typeof key == "number"
@@ -1260,33 +1511,98 @@ function OutputStream(options) {
         } else {
             output.print_string(key, quote);
         }
-    }
-
-    DEFPRINT(AST_ObjectKeyVal, function(self, output){
-        print_property_name(self.key, self.quote, output);
-        output.colon();
-        self.value.print(output);
     });
-    AST_ObjectProperty.DEFMETHOD("_print_getter_setter", function(type, output) {
+    DEFPRINT(AST_ObjectKeyVal, function(self, output){
+        function get_name(self) {
+            var def = self.definition();
+            return def ? def.mangled_name || def.name : self.name;
+        }
+
+        var allowShortHand = output.option("shorthand");
+        if (allowShortHand &&
+            self.value instanceof AST_Symbol &&
+            is_identifier_string(self.key) &&
+            get_name(self.value) === self.key
+        ) {
+            self.print_property_name(self.key, self.quote, output);
+
+        } else if (allowShortHand &&
+            self.value instanceof AST_DefaultAssign &&
+            self.value.left instanceof AST_Symbol &&
+            is_identifier_string(self.key) &&
+            get_name(self.value.left) === self.key
+        ) {
+            self.print_property_name(self.key, self.quote, output);
+            output.print("=");
+            self.value.right.print(output);
+        } else {
+            if (!(self.key instanceof AST_Node)) {
+                self.print_property_name(self.key, self.quote, output);
+            } else {
+                output.with_square(function() {
+                    self.key.print(output);
+                });
+            }
+            output.colon();
+            self.value.print(output);
+        }
+    });
+    AST_ObjectProperty.DEFMETHOD("_print_getter_setter", function(type, self, output) {
+        if (self.static) {
+            output.print("static");
+            output.space();
+        }
         output.print(type);
         output.space();
-        print_property_name(this.key.name, this.quote, output);
-        this.value._do_print(output, true);
+        if (self.key instanceof AST_SymbolMethod) {
+            self.print_property_name(self.key.name, self.quote, output);
+        } else {
+            output.with_square(function() {
+                self.key.print(output);
+            });
+        }
+        self.value._do_print(output, true);
     });
     DEFPRINT(AST_ObjectSetter, function(self, output){
-        self._print_getter_setter("set", output);
+        self._print_getter_setter("set", self, output);
     });
     DEFPRINT(AST_ObjectGetter, function(self, output){
-        self._print_getter_setter("get", output);
+        self._print_getter_setter("get", self, output);
     });
-    DEFPRINT(AST_Symbol, function(self, output){
-        var def = self.definition();
-        output.print_name(def ? def.mangled_name || def.name : self.name);
+    DEFPRINT(AST_ConciseMethod, function(self, output){
+        if (self.static) {
+            output.print("static");
+            output.space();
+        }
+        if (self.is_generator) {
+            output.print("*");
+        }
+        if (self.key instanceof AST_SymbolMethod) {
+            self.print_property_name(self.key.name, self.quote, output);
+        } else {
+            output.with_square(function() {
+                self.key.print(output);
+            });
+        }
+        self.value._do_print(output, true);
+    });
+    AST_Symbol.DEFMETHOD("_do_print", function(output){
+        var def = this.definition();
+        output.print_name(def ? def.mangled_name || def.name : this.name);
+    });
+    DEFPRINT(AST_Symbol, function (self, output) {
+        self._do_print(output);
+    });
+    DEFPRINT(AST_SymbolDeclaration, function(self, output){
+        self._do_print(output);
     });
     DEFPRINT(AST_Hole, noop);
     DEFPRINT(AST_This, function(self, output){
         output.print("this");
     });
+    DEFPRINT(AST_Super, function(self, output){
+        output.print("super");
+    });
     DEFPRINT(AST_Constant, function(self, output){
         output.print(self.getValue());
     });
@@ -1301,14 +1617,45 @@ function OutputStream(options) {
         }
     });
 
+    function regexp_safe_literal(code) {
+        return [
+            0x5c   , // \
+            0x2f   , // /
+            0x2e   , // .
+            0x2b   , // +
+            0x2a   , // *
+            0x3f   , // ?
+            0x28   , // (
+            0x29   , // )
+            0x5b   , // [
+            0x5d   , // ]
+            0x7b   , // {
+            0x7d   , // }
+            0x24   , // $
+            0x5e   , // ^
+            0x3a   , // :
+            0x7c   , // |
+            0x21   , // !
+            0x0a   , // \n
+            0x0d   , // \r
+            0x00   , // \0
+            0xfeff , // Unicode BOM
+            0x2028 , // unicode "line separator"
+            0x2029 , // unicode "paragraph separator"
+        ].indexOf(code) < 0;
+    };
+
     DEFPRINT(AST_RegExp, function(self, output){
-        var regexp = self.getValue();
-        var str = regexp.toString();
-        if (regexp.raw_source) {
-            str = "/" + regexp.raw_source + str.slice(str.lastIndexOf("/"));
-        }
+        var str = self.getValue().toString();
         if (output.option("ascii_only")) {
             str = output.to_ascii(str);
+        } else if (output.option("unescape_regexps")) {
+            str = str.split("\\\\").map(function(str){
+                return str.replace(/\\u[0-9a-fA-F]{4}|\\x[0-9a-fA-F]{2}/g, function(s){
+                    var code = parseInt(s.substr(2), 16);
+                    return regexp_safe_literal(code) ? String.fromCharCode(code) : s;
+                });
+            }).join("\\\\");
         }
         output.print(str);
         var p = output.parent();

lib/propmangle.js

@@ -44,6 +44,16 @@
 "use strict";
 
 function find_builtins(reserved) {
+
+    // Compatibility fix for some standard defined globals not defined on every js environment
+    var new_globals = ["Symbol", "Map", "Promise", "Proxy", "Reflect", "Set", "WeakMap", "WeakSet"];
+    var objects = {};
+    var global_ref = typeof global === "object" ? global : self;
+
+    new_globals.forEach(function (new_global) {
+        objects[new_global] = global_ref[new_global] || new Function();
+    });
+
     // NaN will be included due to Number.NaN
     [
         "null",
@@ -55,7 +65,15 @@ function find_builtins(reserved) {
     ].forEach(add);
     [ Object, Array, Function, Number,
       String, Boolean, Error, Math,
-      Date, RegExp
+      Date, RegExp, objects.Symbol, ArrayBuffer,
+      DataView, decodeURI, decodeURIComponent,
+      encodeURI, encodeURIComponent, eval, EvalError,
+      Float32Array, Float64Array, Int8Array, Int16Array,
+      Int32Array, isFinite, isNaN, JSON, objects.Map, parseFloat,
+      parseInt, objects.Promise, objects.Proxy, RangeError, ReferenceError,
+      objects.Reflect, objects.Set, SyntaxError, TypeError, Uint8Array,
+      Uint8ClampedArray, Uint16Array, Uint32Array, URIError,
+      objects.WeakMap, objects.WeakSet
     ].forEach(function(ctor){
         Object.getOwnPropertyNames(ctor).map(add);
         if (ctor.prototype) {
@@ -78,8 +96,7 @@ function mangle_properties(ast, options) {
         reserved: null,
     });
 
-    var reserved = options.reserved;
-    if (!Array.isArray(reserved)) reserved = [];
+    var reserved = options.reserved || [];
     if (!options.builtins) find_builtins(reserved);
 
     var cache = options.cache;
@@ -121,6 +138,9 @@ function mangle_properties(ast, options) {
         else if (node instanceof AST_Sub) {
             addStrings(node.property, keep_quoted);
         }
+        else if (node instanceof AST_ConciseMethod) {
+            add(node.name.name);
+        }
     }));
 
     // step 2: transform the tree, renaming properties
@@ -140,6 +160,11 @@ function mangle_properties(ast, options) {
             if (!keep_quoted)
                 node.property = mangleStrings(node.property);
         }
+        else if (node instanceof AST_ConciseMethod) {
+            if (should_mangle(node.name.name)) {
+                node.name.name = mangle(node.name.name);
+            }
+        }
         // else if (node instanceof AST_String) {
         //     if (should_mangle(node.value)) {
         //         AST_Node.warn(

lib/scope.js

@@ -49,7 +49,9 @@ function SymbolDef(scope, index, orig) {
     this.scope = scope;
     this.references = [];
     this.global = false;
+    this.export = false;
     this.mangled_name = null;
+    this.object_destructuring_arg = false;
     this.undeclared = false;
     this.index = index;
     this.id = SymbolDef.next_id++;
@@ -62,11 +64,17 @@ SymbolDef.prototype = {
         if (!options) options = {};
 
         return (this.global && !options.toplevel)
+            || this.export
+            || this.object_destructuring_arg
             || this.undeclared
             || (!options.eval && (this.scope.uses_eval || this.scope.uses_with))
             || (options.keep_fnames
                 && (this.orig[0] instanceof AST_SymbolLambda
-                    || this.orig[0] instanceof AST_SymbolDefun));
+                    || this.orig[0] instanceof AST_SymbolDefun))
+            || this.orig[0] instanceof AST_SymbolMethod
+            || (options.keep_classnames
+                && (this.orig[0] instanceof AST_SymbolClass
+                    || this.orig[0] instanceof AST_SymbolDefClass));
     },
     mangle: function(options) {
         var cache = options.cache && options.cache.props;
@@ -94,6 +102,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
     options = defaults(options, {
         cache: null,
         ie8: false,
+        safari10: false,
     });
 
     // pass 1: setup scope chaining and handle definitions
@@ -101,15 +110,35 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
     var scope = self.parent_scope = null;
     var labels = new Dictionary();
     var defun = null;
+    var in_destructuring = null;
+    var in_export = false;
+    var in_block = 0;
+    var for_scopes = [];
     var tw = new TreeWalker(function(node, descend){
-        if (node instanceof AST_Catch) {
+        if (node.is_block_scope()) {
             var save_scope = scope;
             scope = new AST_Scope(node);
             scope.init_scope_vars(save_scope);
+            if (!(node instanceof AST_Scope)) {
+                scope.uses_with = save_scope.uses_with;
+                scope.uses_eval = save_scope.uses_eval;
+                scope.directives = save_scope.directives;
+            }
+            if (options.safari10) {
+                if (node instanceof AST_For || node instanceof AST_ForIn) {
+                    for_scopes.push(scope);
+                }
+            }
             descend();
             scope = save_scope;
             return true;
         }
+        if (node instanceof AST_Destructuring && node.is_array === false) {
+            in_destructuring = node;  // These don't nest
+            descend();
+            in_destructuring = null;
+            return true;
+        }
         if (node instanceof AST_Scope) {
             node.init_scope_vars(scope);
             var save_scope = scope;
@@ -123,6 +152,22 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
             labels = save_labels;
             return true;        // don't descend again in TreeWalker
         }
+        if (node instanceof AST_Export) {
+            in_export = true;
+            descend();
+            in_export = false;
+            return true;
+        }
+        if (node instanceof AST_BlockStatement
+            || node instanceof AST_Switch
+            || node instanceof AST_Try
+            || node instanceof AST_Catch
+            || node instanceof AST_Finally) {
+            in_block++;
+            descend();
+            in_block--;
+            return true;
+        }
         if (node instanceof AST_LabeledStatement) {
             var l = node.label;
             if (labels.has(l.name)) {
@@ -141,12 +186,15 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
         if (node instanceof AST_Symbol) {
             node.scope = scope;
         }
+        if (node instanceof AST_SymbolFunarg) {
+            node.object_destructuring_arg = !!in_destructuring;
+        }
         if (node instanceof AST_Label) {
             node.thedef = node;
             node.references = [];
         }
         if (node instanceof AST_SymbolLambda) {
-            defun.def_function(node);
+            defun.def_function(node, in_export, in_block);
         }
         else if (node instanceof AST_SymbolDefun) {
             // Careful here, the scope where this should be defined is
@@ -154,10 +202,28 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
             // scope when we encounter the AST_Defun node (which is
             // instanceof AST_Scope) but we get to the symbol a bit
             // later.
-            (node.scope = defun.parent_scope).def_function(node);
+            var parent_lambda = defun.parent_scope;
+            while (parent_lambda.is_block_scope()) {
+                parent_lambda = parent_lambda.parent_scope;
+            }
+            (node.scope = parent_lambda).def_function(node, in_export, in_block);
         }
-        else if (node instanceof AST_SymbolVar) {
-            defun.def_variable(node);
+        else if (node instanceof AST_SymbolClass) {
+            defun.def_variable(node, in_export, in_block);
+        }
+        else if (node instanceof AST_SymbolImport) {
+            scope.def_variable(node, in_export, in_block);
+        }
+        else if (node instanceof AST_SymbolDefClass) {
+            // This deals with the name of the class being available
+            // inside the class.
+            (node.scope = defun.parent_scope).def_function(node, in_export, in_block);
+        }
+        else if (node instanceof AST_SymbolVar
+            || node instanceof AST_SymbolLet
+            || node instanceof AST_SymbolConst) {
+            var def = ((node instanceof AST_SymbolBlockDeclaration) ? scope : defun).def_variable(node, in_export, in_block);
+            def.destructuring = in_destructuring;
             if (defun !== scope) {
                 node.mark_enclosed(options);
                 var def = scope.find_variable(node);
@@ -168,7 +234,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
             }
         }
         else if (node instanceof AST_SymbolCatch) {
-            scope.def_variable(node).defun = defun;
+            scope.def_variable(node, in_export, in_block).defun = defun;
         }
         else if (node instanceof AST_LabelRef) {
             var sym = labels.get(node.name);
@@ -183,8 +249,24 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
     self.walk(tw);
 
     // pass 2: find back references and eval
-    self.globals = new Dictionary();
+    var func = null;
+    var cls = null;
+    var globals = self.globals = new Dictionary();
     var tw = new TreeWalker(function(node, descend){
+        if (node instanceof AST_Lambda) {
+            var prev_func = func;
+            func = node;
+            descend();
+            func = prev_func;
+            return true;
+        }
+        if (node instanceof AST_Class) {
+            var prev_cls = cls;
+            cls = node;
+            descend();
+            cls = prev_cls;
+            return true;
+        }
         if (node instanceof AST_LoopControl && node.label) {
             node.label.thedef.references.push(node);
             return true;
@@ -197,10 +279,11 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
                 }
             }
             var sym = node.scope.find_variable(name);
+            if (node.scope instanceof AST_Lambda && name == "arguments") {
+                node.scope.uses_arguments = true;
+            }
             if (!sym) {
                 sym = self.def_global(node);
-            } else if (sym.scope instanceof AST_Lambda && name == "arguments") {
-                sym.scope.uses_arguments = true;
             }
             node.thedef = sym;
             node.reference(options);
@@ -227,6 +310,19 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
         }));
     }
 
+    // pass 4: add symbol definitions to loop scopes
+    // Safari/Webkit bug workaround - loop init let variable shadowing argument.
+    // https://github.com/mishoo/UglifyJS2/issues/1753
+    // https://bugs.webkit.org/show_bug.cgi?id=171041
+    if (options.safari10) {
+        for (var i = 0; i < for_scopes.length; i++) {
+            var scope = for_scopes[i];
+            scope.parent_scope.variables.each(function(def) {
+                push_uniq(scope.enclosed, def);
+            });
+        }
+    }
+
     if (options.cache) {
         this.cname = options.cache.cname;
     }
@@ -255,10 +351,27 @@ AST_Scope.DEFMETHOD("init_scope_vars", function(parent_scope){
     this.cname = -1;                    // the current index for mangling functions/variables
 });
 
+AST_Node.DEFMETHOD("is_block_scope", function(){
+    return false; // Behaviour will be overridden by AST_Block
+});
+
+AST_Block.DEFMETHOD("is_block_scope", function(){
+    return (
+        !(this instanceof AST_Lambda) &&
+        !(this instanceof AST_Toplevel) &&
+        !(this instanceof AST_Class) &&
+        !(this instanceof AST_SwitchBranch)
+    );
+});
+
+AST_IterationStatement.DEFMETHOD("is_block_scope", function(){
+     return true;
+});
+
 AST_Lambda.DEFMETHOD("init_scope_vars", function(){
     AST_Scope.prototype.init_scope_vars.apply(this, arguments);
     this.uses_arguments = false;
-    this.def_variable(new AST_SymbolFunarg({
+    this.def_variable(new AST_SymbolConst({
         name: "arguments",
         start: this.start,
         end: this.end
@@ -291,16 +404,24 @@ AST_Scope.DEFMETHOD("find_variable", function(name){
         || (this.parent_scope && this.parent_scope.find_variable(name));
 });
 
-AST_Scope.DEFMETHOD("def_function", function(symbol){
-    this.functions.set(symbol.name, this.def_variable(symbol));
+AST_Scope.DEFMETHOD("def_function", function(symbol, in_export, in_block){
+    this.functions.set(symbol.name, this.def_variable(symbol, in_export, in_block));
 });
 
-AST_Scope.DEFMETHOD("def_variable", function(symbol){
+AST_Scope.DEFMETHOD("def_variable", function(symbol, in_export, in_block){
     var def;
     if (!this.variables.has(symbol.name)) {
         def = new SymbolDef(this, this.variables.size(), symbol);
         this.variables.set(symbol.name, def);
-        def.global = !this.parent_scope;
+        def.object_destructuring_arg = symbol.object_destructuring_arg;
+        if (in_export) {
+            def.export = true;
+        }
+        if (in_block && symbol instanceof AST_SymbolBlockDeclaration) {
+            def.global = false;
+        } else {
+            def.global = !this.parent_scope;
+        }
     } else {
         def = this.variables.get(symbol.name);
         def.orig.push(symbol);
@@ -348,11 +469,19 @@ AST_Function.DEFMETHOD("next_mangled", function(options, def){
 });
 
 AST_Symbol.DEFMETHOD("unmangleable", function(options){
-    return this.definition().unmangleable(options);
+    var def = this.definition();
+    return def && def.unmangleable(options);
+});
+
+// property accessors are not mangleable
+AST_SymbolAccessor.DEFMETHOD("unmangleable", function(){
+    return true;
 });
 
 // labels are always mangleable
-AST_Label.DEFMETHOD("unmangleable", return_false);
+AST_Label.DEFMETHOD("unmangleable", function(){
+    return false;
+});
 
 AST_Symbol.DEFMETHOD("unreferenced", function(){
     return this.definition().references.length == 0
@@ -363,9 +492,13 @@ AST_Symbol.DEFMETHOD("undeclared", function(){
     return this.definition().undeclared;
 });
 
-AST_LabelRef.DEFMETHOD("undeclared", return_false);
+AST_LabelRef.DEFMETHOD("undeclared", function(){
+    return false;
+});
 
-AST_Label.DEFMETHOD("undeclared", return_false);
+AST_Label.DEFMETHOD("undeclared", function(){
+    return false;
+});
 
 AST_Symbol.DEFMETHOD("definition", function(){
     return this.thedef;
@@ -376,15 +509,14 @@ AST_Symbol.DEFMETHOD("global", function(){
 });
 
 AST_Toplevel.DEFMETHOD("_default_mangler_options", function(options){
-    options = defaults(options, {
+    return defaults(options, {
         eval        : false,
         ie8         : false,
+        keep_classnames: false,
         keep_fnames : false,
         reserved    : [],
         toplevel    : false,
     });
-    if (!Array.isArray(options.reserved)) options.reserved = [];
-    return options;
 });
 
 AST_Toplevel.DEFMETHOD("mangle_names", function(options){
@@ -432,13 +564,19 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options){
             node.mangled_name = name;
             return true;
         }
-        if (!options.ie8 && node instanceof AST_SymbolCatch) {
+        var mangle_with_block_scope =
+            (!options.ie8 && node instanceof AST_SymbolCatch) ||
+            node instanceof AST_SymbolBlockDeclaration;
+        if (mangle_with_block_scope) {
             to_mangle.push(node.definition());
             return;
         }
     });
     this.walk(tw);
-    to_mangle.forEach(function(def){ def.mangle(options) });
+    to_mangle.forEach(function(def){
+        if (def.destructuring && !def.destructuring.is_array) return;
+        def.mangle(options);
+    });
 
     if (options.cache) {
         options.cache.cname = this.cname;
@@ -472,6 +610,8 @@ AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options){
         }
         else if (node instanceof AST_Var)
             base54.consider("var");
+        else if (node instanceof AST_Const)
+            base54.consider("const");
         else if (node instanceof AST_Lambda)
             base54.consider("function");
         else if (node instanceof AST_For)
@@ -487,21 +627,27 @@ AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options){
         else if (node instanceof AST_With)
             base54.consider("with");
         else if (node instanceof AST_ObjectSetter)
-            base54.consider("set" + node.key);
+            base54.consider("set" + (typeof node.key === "string" ? node.key : ""));
         else if (node instanceof AST_ObjectGetter)
-            base54.consider("get" + node.key);
-        else if (node instanceof AST_ObjectKeyVal)
+            base54.consider("get" + (typeof node.key === "string" ? node.key : ""));
+        else if (node instanceof AST_ObjectKeyVal && typeof node.key === "string")
+            base54.consider(node.key);
+        else if (node instanceof AST_ConciseMethod && typeof node.key === "string")
             base54.consider(node.key);
         else if (node instanceof AST_New)
             base54.consider("new");
         else if (node instanceof AST_This)
             base54.consider("this");
+        else if (node instanceof AST_Super)
+            base54.consider("super");
         else if (node instanceof AST_Try)
             base54.consider("try");
         else if (node instanceof AST_Catch)
             base54.consider("catch");
         else if (node instanceof AST_Finally)
             base54.consider("finally");
+        else if (node instanceof AST_Yield)
+            base54.consider("yield");
         else if (node instanceof AST_Symbol && node.unmangleable(options))
             base54.consider(node.name);
         else if (node instanceof AST_Unary || node instanceof AST_Binary)

lib/transform.js

@@ -163,10 +163,18 @@ TreeTransformer.prototype = new TreeWalker;
         if (self.value) self.value = self.value.transform(tw);
     });
 
+    _(AST_Destructuring, function(self, tw) {
+        self.names = do_list(self.names, tw);
+    });
+
     _(AST_Lambda, function(self, tw){
         if (self.name) self.name = self.name.transform(tw);
         self.argnames = do_list(self.argnames, tw);
-        self.body = do_list(self.body, tw);
+        if (self.body instanceof AST_Node) {
+            self.body = self.body.transform(tw);
+        } else {
+            self.body = do_list(self.body, tw);
+        }
     });
 
     _(AST_Call, function(self, tw){
@@ -187,6 +195,10 @@ TreeTransformer.prototype = new TreeWalker;
         self.property = self.property.transform(tw);
     });
 
+    _(AST_Yield, function(self, tw){
+        if (self.expression) self.expression = self.expression.transform(tw);
+    });
+
     _(AST_Unary, function(self, tw){
         self.expression = self.expression.transform(tw);
     });
@@ -211,7 +223,32 @@ TreeTransformer.prototype = new TreeWalker;
     });
 
     _(AST_ObjectProperty, function(self, tw){
+        if (self.key instanceof AST_Node) {
+            self.key = self.key.transform(tw);
+        }
         self.value = self.value.transform(tw);
     });
 
+    _(AST_Class, function(self, tw){
+        if (self.name) self.name = self.name.transform(tw);
+        if (self.extends) self.extends = self.extends.transform(tw);
+        self.properties = do_list(self.properties, tw);
+    });
+
+    _(AST_Expansion, function(self, tw){
+        self.expression = self.expression.transform(tw);
+    });
+
+    _(AST_TemplateString, function(self, tw) {
+        for (var i = 0; i < self.segments.length; i++) {
+            if (!(self.segments[i] instanceof AST_TemplateSegment)) {
+                self.segments[i] = self.segments[i].transform(tw);
+            }
+        }
+    });
+
+    _(AST_PrefixedTemplateString, function(self, tw) {
+        self.template_string = self.template_string.transform(tw);
+    });
+
 })();

lib/utils.js

@@ -43,6 +43,13 @@
 
 "use strict";
 
+function array_to_hash(a) {
+    var ret = Object.create(null);
+    for (var i = 0; i < a.length; ++i)
+        ret[a[i]] = true;
+    return ret;
+};
+
 function slice(a, start) {
     return Array.prototype.slice.call(a, start || 0);
 };

package.json

@@ -1,10 +1,10 @@
 {
-  "name": "uglify-js",
+  "name": "uglify-es",
   "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
   "homepage": "http://lisperator.net/uglifyjs",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.0.17",
+  "version": "3.0.4",
   "engines": {
     "node": ">=0.8.0"
   },
@@ -33,12 +33,22 @@
     "source-map": "~0.5.1"
   },
   "devDependencies": {
-    "acorn": "~5.0.3",
-    "mocha": "~2.3.4",
-    "semver": "~5.3.0"
+    "acorn": "~0.6.0",
+    "escodegen": "~1.3.3",
+    "esfuzz": "~0.3.1",
+    "estraverse": "~1.5.1",
+    "mocha": "~2.3.4"
+  },
+  "optionalDependencies": {
+    "uglify-to-browserify": "~1.0.0"
+  },
+  "browserify": {
+    "transform": [
+      "uglify-to-browserify"
+    ]
   },
   "scripts": {
     "test": "node test/run-tests.js"
   },
-  "keywords": ["uglify", "uglify-js", "minify", "minifier", "es5"]
+  "keywords": ["uglify", "uglify-js", "minify", "minifier"]
 }

test/benchmark.js

@@ -4,13 +4,12 @@
 "use strict";
 
 var createHash = require("crypto").createHash;
-var fetch = require("./fetch");
 var fork = require("child_process").fork;
 var args = process.argv.slice(2);
 if (!args.length) {
     args.push("-mc");
 }
-args.push("--timings");
+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",
@@ -30,7 +29,12 @@ function done() {
             var info = results[url];
             console.log();
             console.log(url);
-            console.log(info.log);
+            var elapsed = 0;
+            console.log(info.log.replace(/Elapsed: ([0-9]+)\s*/g, function(match, time) {
+                elapsed += 1e-3 * parseInt(time);
+                return "";
+            }));
+            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);
@@ -53,8 +57,7 @@ urls.forEach(function(url) {
         output: 0,
         log: ""
     };
-    fetch(url, function(err, res) {
-        if (err) throw err;
+    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;

test/compress/arrays.js

@@ -1,3 +1,5 @@
+// NOTE trailing comma doesn't contribute to length of an array
+// That also means the array changes length if previous element is a hole too and got cut off
 holes_and_undefined: {
     input: {
         w = [1,,];
@@ -91,6 +93,79 @@ constant_join_2: {
     }
 }
 
+spread_with_variable_as_last_element: {
+    input: {
+        var values = [4, 5, 6];
+        var a = [1, 2, 3, ...values];
+    }
+    expect: {
+        var values = [4, 5, 6];
+        var a = [1, 2, 3, ...values];
+    }
+}
+
+spread_with_variable_in_middle: {
+    input: {
+        var values = [4, 5, 6];
+        var a = [1, 2, 3, ...values, 7,,,];
+    }
+    expect: {
+        var values = [4, 5, 6];
+        var a = [1, 2, 3, ...values, 7,,,];
+    }
+}
+
+spread_with_variable_at_front: {
+    input: {
+        var values = [1, 2, 3];
+        var a = [...values, 4, 5, 6];
+    }
+    expect: {
+        var values = [1, 2, 3];
+        var a = [...values, 4, 5, 6];
+    }
+}
+
+spread_with_variable_at_front_after_elisions: {
+    input: {
+        var values = [1, 2, 3];
+        var a = [,,,...values, 4, 5, 6];
+    }
+    expect: {
+        var values = [1, 2, 3];
+        var a = [,,,...values, 4, 5, 6];
+    }
+}
+
+spread_with_array_at_end: {
+    input: {
+        var a = [1, 2, ...[4, 5, 6]];
+    }
+    expect: {
+        var a = [1, 2, ...[4, 5, 6]];
+    }
+}
+
+spread_with_logical_expression_at_end: {
+    options = { evaluate: true }
+    input: {
+        var a = [1, 2, 3, ...[2+2]]
+    }
+    expect: {
+        var a = [1, 2, 3, ...[4]]
+    }
+}
+
+spread_with_logical_expression_at_middle: {
+    options = { evaluate: true }
+    input: {
+        var a = [1, 1, ...[1+1, 1+2, 2+3], 8]
+    }
+    expect: {
+        var a = [1, 1, ...[2, 3, 5], 8]
+    }
+}
+
 constant_join_3: {
     options = {
         unsafe: true,

test/compress/arrow.js

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

test/compress/block-scope.js

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

test/compress/collapse_vars.js

@@ -583,8 +583,8 @@ collapse_vars_assignment: {
             return a = a;
         }
         function f1(c) {
-            var a = 3 / c;
-            var b = 1 - a;
+            const a = 3 / c;
+            const b = 1 - a;
             return b;
         }
         function f2(c) {
@@ -724,10 +724,10 @@ collapse_vars_misc1: {
             return t;
         }
         function f1(x) { var y = 5 - x; return y; }
-        function f2(x) { var z = foo(), y = z / (5 - x); return y; }
+        function f2(x) { const z = foo(), y = z / (5 - x); return y; }
         function f3(x) { var z = foo(), y = (5 - x) / z; return y; }
         function f4(x) { var z = foo(), y = (5 - u) / z; return y; }
-        function f5(x) { var z = foo(), y = (5 - window.x) / z; return y; }
+        function f5(x) { const z = foo(), y = (5 - window.x) / z; return y; }
         function f6() { var b = window.a * window.z; return b && zap(); }
         function f7() { var b = window.a * window.z; return b + b; }
         function f8() { var b = window.a * window.z; var c = b + 5; return b + c; }
@@ -744,7 +744,7 @@ collapse_vars_misc1: {
         function f2(x) { return foo() / (5 - x) }
         function f3(x) { return (5 - x) / foo() }
         function f4(x) { var z = foo(); return (5 - u) / z }
-        function f5(x) { var z = foo(); return (5 - window.x) / z }
+        function f5(x) { const z = foo(); return (5 - window.x) / z }
         function f6() { return window.a * window.z && zap() }
         function f7() { var b = window.a * window.z; return b + b }
         function f8() { var b = window.a * window.z; return b + (b + 5) }
@@ -1146,7 +1146,7 @@ collapse_vars_constants: {
         function f3(x) {
             var b = x.prop;
             sideeffect1();
-            return b + (function() { return -9; })();
+            return b + -9;
         }
     }
 }
@@ -1328,6 +1328,7 @@ collapse_vars_regexp: {
 issue_1537: {
     options = {
         collapse_vars: true,
+        toplevel: true,
     }
     input: {
         var k = '';
@@ -1339,6 +1340,104 @@ issue_1537: {
     }
 }
 
+issue_1537_for_of: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var k = '';
+        for (k of {prop: 'val'}){}
+    }
+    expect: {
+        var k = '';
+        for (k of {prop: 'val'});
+    }
+}
+
+issue_1537_destructuring_1: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var x = 1, y = 2;
+        [x] = [y];
+    }
+    expect: {
+        var x = 1, y = 2;
+        [x] = [y];
+    }
+}
+
+issue_1537_destructuring_2: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var x = foo();
+        [x] = [1];
+    }
+    expect: {
+        var x = foo();
+        [x] = [1];
+    }
+}
+
+issue_1537_destructuring_3: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var x = Math.random();
+        ({p: x = 9} = {v: 1});
+    }
+    expect: {
+        var x = Math.random();
+        ({p: x = 9} = {v: 1});
+    }
+}
+
+issue_1537_destructuring_for_in: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var x = 1, y = 2;
+        (function() {
+            for ([[x], y] in a);
+        })();
+    }
+    expect: {
+        var x = 1, y = 2;
+        (function() {
+            for ([[x], y] in a);
+        })();
+    }
+}
+
+issue_1537_destructuring_for_of: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var x = 1, y = 2;
+        (function() {
+            for ([[x], y] of a);
+        })();
+    }
+    expect: {
+        var x = 1, y = 2;
+        (function() {
+            for ([[x], y] of a);
+        })();
+    }
+}
+
 issue_1562: {
     options = {
         collapse_vars: true,
@@ -2104,11 +2203,10 @@ unused_orig: {
     expect: {
         var a = 1;
         console.log(function(b) {
+            var a;
             var c = b;
-            for (var d in c) {
-                var a = c[0];
-                return --b + a;
-            }
+            for (var d in c)
+                return --b + (a = c[0]);
             a && a.NaN;
         }([2]), a);
     }
@@ -2186,3 +2284,49 @@ compound_assignment: {
     }
     expect_stdout: "4"
 }
+
+reassign_const_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        function f() {
+            const a = 1;
+            a = 2;
+            return a;
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            const a = 1;
+            a = 2;
+            return a;
+        }
+        console.log(f());
+    }
+    expect_stdout: true
+}
+
+reassign_const_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        function f() {
+            const a = 1;
+            ++a;
+            return a;
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            const a = 1;
+            ++a;
+            return a;
+        }
+        console.log(f());
+    }
+    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

@@ -31,7 +31,7 @@ dead_code_2_should_warn: {
         function f() {
             g();
             x = 10;
-            throw new Error("foo");
+            throw "foo";
             // completely discarding the `if` would introduce some
             // bugs.  UglifyJS v1 doesn't deal with this issue; in v2
             // we copy any declarations to the upper scope.
@@ -46,60 +46,16 @@ dead_code_2_should_warn: {
                 })();
             }
         }
-        f();
     }
     expect: {
         function f() {
             g();
             x = 10;
-            throw new Error("foo");
+            throw "foo";
             var x;
             function g(){};
         }
-        f();
     }
-    expect_stdout: true
-    node_version: "<=4"
-}
-
-dead_code_2_should_warn_strict: {
-    options = {
-        dead_code: true
-    };
-    input: {
-        "use strict";
-        function f() {
-            g();
-            x = 10;
-            throw new Error("foo");
-            // completely discarding the `if` would introduce some
-            // bugs.  UglifyJS v1 doesn't deal with this issue; in v2
-            // we copy any declarations to the upper scope.
-            if (x) {
-                y();
-                var x;
-                function g(){};
-                // but nested declarations should not be kept.
-                (function(){
-                    var q;
-                    function y(){};
-                })();
-            }
-        }
-        f();
-    }
-    expect: {
-        "use strict";
-        function f() {
-            g();
-            x = 10;
-            throw new Error("foo");
-            var x;
-        }
-        f();
-    }
-    expect_stdout: true
-    node_version: ">=4"
 }
 
 dead_code_constant_boolean_should_warn_more: {
@@ -122,7 +78,6 @@ dead_code_constant_boolean_should_warn_more: {
             foo();
             var moo;
         }
-        bar();
     }
     expect: {
         var foo;
@@ -131,46 +86,155 @@ dead_code_constant_boolean_should_warn_more: {
         // as for the for, it should keep:
         var x = 10, y;
         var moo;
-        bar();
     }
     expect_stdout: true
-    node_version: "<=4"
 }
 
-dead_code_constant_boolean_should_warn_more_strict: {
+dead_code_block_decls_die: {
+    options = {
+        dead_code    : true,
+        conditionals : true,
+        booleans     : true,
+        evaluate     : true
+    };
+    input: {
+        if (0) {
+            let foo = 6;
+            const bar = 12;
+            class Baz {};
+            var qux;
+        }
+        console.log(foo, bar, Baz);
+    }
+    expect: {
+        var qux;
+        console.log(foo, bar, Baz);
+    }
+}
+
+dead_code_const_declaration: {
     options = {
         dead_code    : true,
         loops        : true,
         booleans     : true,
         conditionals : true,
         evaluate     : true,
-        side_effects : true,
+        reduce_vars  : true,
     };
     input: {
-        "use strict";
-        while (!((foo && bar) || (x + "0"))) {
+        var unused;
+        const CONST_FOO = false;
+        if (CONST_FOO) {
             console.log("unreachable");
-            var foo;
+            var moo;
             function bar() {}
         }
-        for (var x = 10, y; x && (y || x) && (!typeof x); ++x) {
-            asdf();
-            foo();
-            var moo;
-        }
-        bar();
     }
     expect: {
-        "use strict";
-        var foo;
-        // nothing for the while
-        // as for the for, it should keep:
-        var x = 10, y;
+        var unused;
+        const CONST_FOO = !1;
         var moo;
-        bar();
+        function bar() {}
+    }
+    expect_stdout: true
+}
+
+dead_code_const_annotation: {
+    options = {
+        dead_code    : true,
+        loops        : true,
+        booleans     : true,
+        conditionals : true,
+        evaluate     : true,
+        reduce_vars  : true,
+        toplevel     : true,
+    };
+    input: {
+        var unused;
+        /** @const */ var CONST_FOO_ANN = false;
+        if (CONST_FOO_ANN) {
+            console.log("unreachable");
+            var moo;
+            function bar() {}
+        }
+    }
+    expect: {
+        var unused;
+        var CONST_FOO_ANN = !1;
+        var moo;
+        function bar() {}
+    }
+    expect_stdout: true
+}
+
+dead_code_const_annotation_regex: {
+    options = {
+        dead_code    : true,
+        loops        : true,
+        booleans     : true,
+        conditionals : true,
+        evaluate     : true
+    };
+    input: {
+        var unused;
+        // @constraint this shouldn't be a constant
+        var CONST_FOO_ANN = false;
+        if (CONST_FOO_ANN) {
+            console.log("reachable");
+        }
+    }
+    expect: {
+        var unused;
+        var CONST_FOO_ANN = !1;
+        CONST_FOO_ANN && console.log('reachable');
+    }
+    expect_stdout: true
+}
+
+dead_code_const_annotation_complex_scope: {
+    options = {
+        dead_code    : true,
+        loops        : true,
+        booleans     : true,
+        conditionals : true,
+        evaluate     : true,
+        reduce_vars  : true,
+        toplevel     : true,
+    };
+    input: {
+        var unused_var;
+        /** @const */ var test = 'test';
+        // @const
+        var CONST_FOO_ANN = false;
+        var unused_var_2;
+        if (CONST_FOO_ANN) {
+            console.log("unreachable");
+            var moo;
+            function bar() {}
+        }
+        if (test === 'test') {
+            var beef = 'good';
+            /** @const */ var meat = 'beef';
+            var pork = 'bad';
+            if (meat === 'pork') {
+                console.log('also unreachable');
+            } else if (pork === 'good') {
+                console.log('reached, not const');
+            }
+        }
+    }
+    expect: {
+        var unused_var;
+        var test = 'test';
+        var CONST_FOO_ANN = !1;
+        var unused_var_2;
+        var moo;
+        function bar() {}
+        var beef = 'good';
+        var meat = 'beef';
+        var pork = 'bad';
     }
     expect_stdout: true
-    node_version: ">=4"
 }
 
 try_catch_finally: {
@@ -214,19 +278,3 @@ try_catch_finally: {
         "1",
     ]
 }
-
-accessor: {
-    options = {
-        side_effects: true,
-    }
-    input: {
-        ({
-            get a() {},
-            set a(v){
-                this.b = 2;
-            },
-            b: 1
-        });
-    }
-    expect: {}
-}

test/compress/destructuring.js

@@ -0,0 +1,332 @@
+destructuring_arrays: {
+    input: {
+        {const [aa, bb] = cc;}
+        {const [aa, [bb, cc]] = dd;}
+        {let [aa, bb] = cc;}
+        {let [aa, [bb, cc]] = dd;}
+        var [aa, bb] = cc;
+        var [aa, [bb, cc]] = dd;
+        var [,[,,,,,],,,zz,] = xx; // Trailing comma
+        var [,,zzz,,] = xxx; // Trailing comma after hole
+    }
+    expect: {
+        {const [aa, bb] = cc;}
+        {const [aa, [bb, cc]] = dd;}
+        {let [aa, bb] = cc;}
+        {let [aa, [bb, cc]] = dd;}
+        var [aa, bb] = cc;
+        var [aa, [bb, cc]] = dd;
+        var [,[,,,,,],,,zz] = xx;
+        var [,,zzz,,] = xxx;
+    }
+}
+
+destructuring_arrays_holes: {
+    input: {
+        var [,,,,] = a;
+        var [,,b,] = c;
+        var [d,,]  = e;
+    }
+    expect_exact: "var[,,,,]=a;var[,,b]=c;var[d,,]=e;"
+}
+
+destructuring_objects: {
+    input: {
+        {const {aa, bb} = {aa:1, bb:2};}
+        {const {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        {let {aa, bb} = {aa:1, bb:2};}
+        {let {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        var {aa, bb} = {aa:1, bb:2};
+        var {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};
+    }
+    expect: {
+        {const {aa, bb} = {aa:1, bb:2};}
+        {const {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        {let {aa, bb} = {aa:1, bb:2};}
+        {let {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        var {aa, bb} = {aa:1, bb:2};
+        var {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};
+    }
+}
+
+destructuring_objects_trailing_elision: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        var {cc,} = foo;
+    }
+    expect_exact: "var{cc}=foo;"
+}
+
+nested_destructuring_objects: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        const [{a},b] = c;
+        let [{a},b] = c;
+        var [{a},b] = c;
+    }
+    expect_exact: 'const[{a},b]=c;let[{a},b]=c;var[{a},b]=c;';
+}
+
+destructuring_constdef_in_loops: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        for (const [x,y] in pairs);
+        for (const [a] = 0;;);
+        for (const {c} of cees);
+    }
+    expect_exact: "for(const[x,y]in pairs);for(const[a]=0;;);for(const{c}of cees);"
+}
+
+destructuring_letdef_in_loops: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        for (let [x,y] in pairs);
+        for (let [a] = 0;;);
+        for (let {c} of cees);
+    }
+    expect_exact: "for(let[x,y]in pairs);for(let[a]=0;;);for(let{c}of cees);"
+}
+
+destructuring_vardef_in_loops: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        for (var [x,y] in pairs);
+        for (var [a] = 0;;);
+        for (var {c} of cees);
+    }
+    expect_exact: "for(var[x,y]in pairs);for(var[a]=0;;);for(var{c}of cees);"
+}
+
+destructuring_expressions: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        ({a, b});
+        [{a}];
+        f({x});
+    }
+    expect_exact: "({a,b});[{a}];f({x});"
+}
+
+destructuring_remove_unused_1: {
+    options = {
+        unused: true
+    }
+    input: {
+        function a() {
+            var unused = "foo";
+            var a = [1];
+            var [b] = a;
+            f(b);
+        }
+        function b() {
+            var unused = "foo";
+            var a = {b: 1};
+            var {b} = a;
+            f(b);
+        }
+        function c() {
+            var unused = "foo";
+            var a = [[1]];
+            var [[b]] = a;
+            f(b);
+        }
+        function d() {
+            var unused = "foo";
+            var a = {b: {b:1}};
+            var {b:{b}} = a;
+            f(b);
+        }
+        function e() {
+            var unused = "foo";
+            var a = [1, 2, 3, 4, 5];
+            var x = [[1, 2, 3]];
+            var y = {h: 1};
+            var [b, ...c] = a;
+            var [...[e, f]] = x;
+            var [...{g: h}] = y;
+            f(b, c, e, f, g);
+        }
+    }
+    expect: {
+        function a() {
+            var a = [1];
+            var [b] = a;
+            f(b);
+        }
+        function b() {
+            var a = {b: 1};
+            var {b} = a;
+            f(b);
+        }
+        function c() {
+            var a = [[1]];
+            var [[b]] = a;
+            f(b);
+        }
+        function d() {
+            var a = {b: {b:1}};
+            var {b:{b}} = a;
+            f(b);
+        }
+        function e() {
+            var a = [1, 2, 3, 4, 5];
+            var x = [[1, 2, 3]];
+            var y = {h: 1};
+            var [b, ...c] = a;
+            var [...[e, f]] = x;
+            var [...{g: h}] = y;
+            f(b, c, e, f, g);
+        }
+    }
+}
+
+destructuring_remove_unused_2: {
+    options = {
+        unused: true
+    }
+    input: {
+        function a() {
+            var unused = "foo";
+            var a = [,,1];
+            var [b] = a;
+            f(b);
+        }
+        function b() {
+            var unused = "foo";
+            var a = [{a: [1]}];
+            var [{b: a}] = a;
+            f(b);
+        }
+    }
+    expect: {
+        function a() {
+            var a = [,,1];
+            var [b] = a;
+            f(b);
+        }
+        function b() {
+            var a = [{a: [1]}];
+            var [{b: a}] = a;
+            f(b);
+        }
+    }
+}
+
+object_destructuring_may_need_parentheses: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        ({a, b} = {a: 1, b: 2});
+    }
+    expect_exact: "({a,b}={a:1,b:2});"
+}
+
+destructuring_with_undefined_as_default_assignment: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        [foo = undefined] = bar;
+        [foo = void 0] = bar;
+    }
+    expect: {
+        [foo] = bar;
+        [foo] = bar;
+    }
+}
+
+destructuring_dont_evaluate_with_undefined_as_default_assignment: {
+    options = {
+        evaluate: false
+    }
+    input: {
+        [foo = undefined] = bar;
+    }
+    expect: {
+        [foo = void 0] = bar;
+    }
+}
+
+reduce_vars: {
+    options = {
+        reduce_vars: true,
+    }
+    input: {
+        {const [aa, [bb, cc]] = dd;}
+        {let [aa, [bb, cc]] = dd;}
+        var [aa, [bb, cc]] = dd;
+        [aa, [bb, cc]] = dd;
+        {const {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        {let {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        var {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};
+        ({aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}});
+        const [{a},b] = c;
+        let [{a},b] = c;
+        var [{a},b] = c;
+        [{a},b] = c;
+        for (const [x,y] in pairs);
+        for (let [x,y] in pairs);
+        for (var [x,y] in pairs);
+        for ([x,y] in pairs);
+    }
+    expect: {
+        {const [aa, [bb, cc]] = dd;}
+        {let [aa, [bb, cc]] = dd;}
+        var [aa, [bb, cc]] = dd;
+        [aa, [bb, cc]] = dd;
+        {const {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        {let {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};}
+        var {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};
+        ({aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}});
+        const [{a},b] = c;
+        let [{a},b] = c;
+        var [{a},b] = c;
+        [{a},b] = c;
+        for (const [x,y] in pairs);
+        for (let [x,y] in pairs);
+        for (var [x,y] in pairs);
+        for ([x,y] in pairs);
+    }
+}
+
+unused: {
+    options = {
+        unused: true,
+    }
+    input: {
+        let { foo: [, , ...a] } = { foo: [1, 2, 3, 4], bar: 5 };
+        console.log(a);
+    }
+    expect: {
+        let { foo: [, , ...a] } = { foo: [1, 2, 3, 4], bar: 5 };
+        console.log(a);
+    }
+}
+
+issue_1886: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        let [a] = [1];
+        console.log(a);
+    }
+    expect: {
+        let [a] = [1];
+        console.log(a);
+    }
+    expect_exact: "1"
+}

test/compress/directives.js

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

test/compress/drop-unused.js

@@ -164,6 +164,87 @@ used_var_in_catch: {
     }
 }
 
+unused_block_decls_in_catch: {
+    options = { unused: true };
+    input: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {
+                let x = 10;
+                const y = 10;
+                class Zee {};
+            }
+        }
+    }
+    expect: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {}
+        }
+    }
+}
+
+used_block_decls_in_catch: {
+    options = { unused: true };
+    input: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {
+                let x = 10;
+                const y = 10;
+                class Zee {};
+            }
+            console.log(x, y, Zee);
+        }
+    }
+    expect: {
+        function foo() {
+            try {
+                foo();
+            } catch(ex) {}
+            console.log(x, y, Zee);
+        }
+    }
+}
+
+unused_block_decls: {
+    options = { unused: true };
+    input: {
+        function foo() {
+            {
+                const x;
+            }
+            {
+                let y;
+            }
+            console.log(x, y);
+        }
+    }
+    expect: {
+        function foo() {
+            console.log(x, y);
+        }
+    }
+}
+
+unused_keep_harmony_destructuring: {
+    options = { unused: true };
+    input: {
+        function foo() {
+            var {x, y} = foo;
+            var a = foo;
+        }
+    }
+    expect:  {
+        function foo() {
+            var {x, y} = foo;
+        }
+    }
+}
+
 keep_fnames: {
     options = { unused: true, keep_fnames: true, unsafe: true };
     input: {
@@ -649,6 +730,37 @@ drop_value: {
     }
 }
 
+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,
@@ -751,12 +863,12 @@ issue_1583: {
     expect: {
         function m(t) {
             (function(e) {
-                t = e();
-            })(function() {
-                return (function(a) {
-                    return a;
-                })(function(a) {});
-            });
+                t = (function() {
+                    return (function(a) {
+                        return a;
+                    })(function(a) {});
+                })();
+            })();
         }
     }
 }
@@ -785,6 +897,10 @@ issue_1709: {
                 var x = 1;
                 return x;
             }(),
+            function y() {
+                const y = 2;
+                return y;
+            }(),
             function z() {
                 function z() {}
                 return z;
@@ -797,6 +913,10 @@ issue_1709: {
                 var x = 1;
                 return x;
             }(),
+            function() {
+                const y = 2;
+                return y;
+            }(),
             function() {
                 function z() {}
                 return z;
@@ -1108,3 +1228,28 @@ var_catch_toplevel: {
         }();
     }
 }
+
+reassign_const: {
+    options = {
+        cascade: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            const a = 1;
+            a = 2;
+            return a;
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            const a = 1;
+            return a = 2, a;
+        }
+        console.log(f());
+    }
+    expect_stdout: true
+}

test/compress/evaluate.js

@@ -224,6 +224,100 @@ positive_zero: {
     expect_stdout: true
 }
 
+pow: {
+    options = { evaluate: true }
+    input: {
+        var a = 5 ** 3;
+    }
+    expect: {
+        var a = 125;
+    }
+}
+
+pow_sequence: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a = 2 ** 3 ** 2;
+    }
+    expect: {
+        var a = 512;
+    }
+}
+
+pow_mixed: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a = 5 + 2 ** 3 + 5;
+        var b = 5 * 3 ** 2;
+        var c = 5 ** 3 * 2;
+        var d = 5 ** +3;
+    }
+    expect: {
+        var a = 18;
+        var b = 45;
+        var c = 250;
+        var d = 125;
+    }
+}
+
+pow_with_right_side_evaluating_to_unary: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a = (4 - 7) ** foo;
+        var b = ++bar ** 3;
+        var c = --baz ** 2;
+    }
+    expect_exact: "var a=(-3)**foo;var b=++bar**3;var c=--baz**2;"
+}
+
+pow_with_number_constants: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a = 5 ** NaN;
+        /* NaN exponent results to NaN */
+        var b = 42 ** +0;
+        /* +0 exponent results to NaN */
+        var c = 42 ** -0;
+        /* -0 exponent results to NaN */
+        var d = NaN ** 1;
+        /* NaN with non-zero exponent is NaN */
+        var e = 2 ** Infinity;
+        /* abs(base) > 1 with Infinity as exponent is Infinity */
+        var f = 2 ** -Infinity;
+        /* abs(base) > 1 with -Infinity as exponent is +0 */
+        var g = (-7) ** (0.5);
+        var h = 2324334 ** 34343443;
+        var i = (-2324334) ** 34343443;
+        var j = 2 ** (-3);
+        var k = 2.0 ** -3;
+        var l = 2.0 ** (5 - 7);
+        var m = 3 ** -10;  // Result will be 0.000016935087808430286, which is too long
+    }
+    expect: {
+        var a = NaN;
+        var b = 1;
+        var c = 1;
+        var d = NaN;
+        var e = 1/0;
+        var f = 0;
+        var g = NaN;
+        var h = 1/0;
+        var i = -1/0;
+        var j = .125;
+        var k = .125;
+        var l = .25;
+        var m = 3 ** -10;
+    }
+}
+
 unsafe_constant: {
     options = {
         evaluate  : true,
@@ -644,19 +738,17 @@ unsafe_prototype_function: {
 call_args: {
     options = {
         evaluate: true,
-        inline: true,
         reduce_vars: true,
-        toplevel: true,
     }
     input: {
-        var a = 1;
+        const a = 1;
         console.log(a);
         +function(a) {
             return a;
         }(a);
     }
     expect: {
-        var a = 1;
+        const a = 1;
         console.log(1);
         +(1, 1);
     }
@@ -666,20 +758,19 @@ call_args: {
 call_args_drop_param: {
     options = {
         evaluate: true,
-        inline: true,
         keep_fargs: false,
         reduce_vars: true,
-        toplevel: true,
         unused: true,
     }
     input: {
-        var a = 1;
+        const a = 1;
         console.log(a);
         +function(a) {
             return a;
         }(a, b);
     }
     expect: {
+        const a = 1;
         console.log(1);
         +(b, 1);
     }
@@ -782,15 +873,13 @@ unsafe_charAt_noop: {
     input: {
         console.log(
             s.charAt(0),
-            "string".charAt(x),
-            (typeof x).charAt()
+            "string".charAt(x)
         );
     }
     expect: {
         console.log(
             s.charAt(0),
-            "string".charAt(x),
-            (typeof x)[0]
+            "string".charAt(x)
         );
     }
 }
@@ -994,78 +1083,3 @@ Infinity_NaN_undefined_LHS: {
         "}",
     ]
 }
-
-issue_1964_1: {
-    options = {
-        evaluate: true,
-        reduce_vars: true,
-        unsafe_regexp: false,
-        unused: true,
-    }
-    input: {
-        function f() {
-            var long_variable_name = /\s/;
-            return "a b c".split(long_variable_name)[1];
-        }
-        console.log(f());
-    }
-    expect: {
-        function f() {
-            var long_variable_name = /\s/;
-            return "a b c".split(long_variable_name)[1];
-        }
-        console.log(f());
-    }
-    expect_stdout: "b"
-}
-
-issue_1964_2: {
-    options = {
-        evaluate: true,
-        reduce_vars: true,
-        unsafe_regexp: true,
-        unused: true,
-    }
-    input: {
-        function f() {
-            var long_variable_name = /\s/;
-            return "a b c".split(long_variable_name)[1];
-        }
-        console.log(f());
-    }
-    expect: {
-        function f() {
-            return "a b c".split(/\s/)[1];
-        }
-        console.log(f());
-    }
-    expect_stdout: "b"
-}
-
-array_slice_index: {
-    options = {
-        evaluate: true,
-        unsafe: true,
-    }
-    input: {
-        console.log([1,2,3].slice(1)[1]);
-    }
-    expect: {
-        console.log(3);
-    }
-    expect_stdout: "3"
-}
-
-string_charCodeAt: {
-    options = {
-        evaluate: true,
-        unsafe: true,
-    }
-    input: {
-        console.log("foo".charCodeAt("bar".length));
-    }
-    expect: {
-        console.log(NaN);
-    }
-    expect_stdout: "NaN"
-}

test/compress/expansions.js

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

test/compress/expression.js

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

test/compress/functions.js

@@ -21,7 +21,6 @@ iifes_returning_constants_keep_fargs_true: {
         join_vars     : true,
         reduce_vars   : true,
         cascade       : true,
-        inline        : true,
     }
     input: {
         (function(){ return -1.23; }());
@@ -57,7 +56,6 @@ iifes_returning_constants_keep_fargs_false: {
         join_vars     : true,
         reduce_vars   : true,
         cascade       : true,
-        inline        : true,
     }
     input: {
         (function(){ return -1.23; }());
@@ -84,7 +82,6 @@ issue_485_crashing_1530: {
         conditionals: true,
         dead_code: true,
         evaluate: true,
-        inline: true,
     }
     input: {
         (function(a) {
@@ -157,7 +154,6 @@ function_returning_constant_literal: {
         evaluate: true,
         cascade: true,
         unused: true,
-        inline: true,
     }
     input: {
         function greeter() {
@@ -171,246 +167,3 @@ function_returning_constant_literal: {
     }
     expect_stdout: "Hello there"
 }
-
-hoist_funs: {
-    options = {
-        hoist_funs: true,
-    }
-    input: {
-        console.log(1, typeof f, typeof g);
-        if (console.log(2, typeof f, typeof g))
-            console.log(3, typeof f, typeof g);
-        else {
-            console.log(4, typeof f, typeof g);
-            function f() {}
-            console.log(5, typeof f, typeof g);
-        }
-        function g() {}
-        console.log(6, typeof f, typeof g);
-    }
-    expect: {
-        function f() {}
-        function g() {}
-        console.log(1, typeof f, typeof g);
-        if (console.log(2, typeof f, typeof g))
-            console.log(3, typeof f, typeof g);
-        else {
-            console.log(4, typeof f, typeof g);
-            console.log(5, typeof f, typeof g);
-        }
-        console.log(6, typeof f, typeof g);
-    }
-    expect_stdout: [
-        "1 'function' 'function'",
-        "2 'function' 'function'",
-        "4 'function' 'function'",
-        "5 'function' 'function'",
-        "6 'function' 'function'",
-    ]
-    node_version: "<=4"
-}
-
-hoist_funs_strict: {
-    options = {
-        hoist_funs: true,
-    }
-    input: {
-        "use strict";
-        console.log(1, typeof f, typeof g);
-        if (console.log(2, typeof f, typeof g))
-            console.log(3, typeof f, typeof g);
-        else {
-            console.log(4, typeof f, typeof g);
-            function f() {}
-            console.log(5, typeof f, typeof g);
-        }
-        function g() {}
-        console.log(6, typeof f, typeof g);
-    }
-    expect: {
-        "use strict";
-        function g() {}
-        console.log(1, typeof f, typeof g);
-        if (console.log(2, typeof f, typeof g))
-            console.log(3, typeof f, typeof g);
-        else {
-            console.log(4, typeof f, typeof g);
-            function f() {}
-            console.log(5, typeof f, typeof g);
-        }
-        console.log(6, typeof f, typeof g);
-    }
-    expect_stdout: [
-        "1 'undefined' 'function'",
-        "2 'undefined' 'function'",
-        "4 'function' 'function'",
-        "5 'function' 'function'",
-        "6 'undefined' 'function'",
-    ]
-    node_version: ">=4"
-}
-
-issue_203: {
-    options = {
-        keep_fargs: false,
-        side_effects: true,
-        unsafe_Func: true,
-        unused: true,
-    }
-    input: {
-        var m = {};
-        var fn = Function("require", "module", "exports", "module.exports = 42;");
-        fn(null, m, m.exports);
-        console.log(m.exports);
-    }
-    expect: {
-        var m = {};
-        var fn = Function("a", "b", "b.exports=42");
-        fn(null, m, m.exports);
-        console.log(m.exports);
-    }
-    expect_stdout: "42"
-}
-
-no_webkit: {
-    beautify = {
-        webkit: false,
-    }
-    input: {
-        console.log(function() {
-            1 + 1;
-        }.a = 1);
-    }
-    expect_exact: "console.log(function(){1+1}.a=1);"
-    expect_stdout: "1"
-}
-
-webkit: {
-    beautify = {
-        webkit: true,
-    }
-    input: {
-        console.log(function() {
-            1 + 1;
-        }.a = 1);
-    }
-    expect_exact: "console.log((function(){1+1}).a=1);"
-    expect_stdout: "1"
-}
-
-issue_2084: {
-    options = {
-        collapse_vars: true,
-        conditionals: true,
-        evaluate: true,
-        inline: true,
-        passes: 2,
-        reduce_vars: true,
-        sequences: true,
-        side_effects: true,
-        unused: true,
-    }
-    input: {
-        var c = 0;
-        !function() {
-            !function(c) {
-                c = 1 + c;
-                var c = 0;
-                function f14(a_1) {
-                    if (c = 1 + c, 0 !== 23..toString())
-                        c = 1 + c, a_1 && (a_1[0] = 0);
-                }
-                f14();
-            }(-1);
-        }();
-        console.log(c);
-    }
-    expect: {
-        var c = 0;
-        !function(c) {
-            c = 1 + c,
-            c = 1 + (c = 0),
-            0 !== 23..toString() && (c = 1 + c);
-        }(-1),
-        console.log(c);
-    }
-    expect_stdout: "0"
-}
-
-issue_2097: {
-    options = {
-        negate_iife: true,
-        reduce_vars: true,
-        toplevel: true,
-        unused: true,
-    }
-    input: {
-        function f() {
-            try {
-                throw 0;
-            } catch (e) {
-                console.log(arguments[0]);
-            }
-        }
-        f(1);
-    }
-    expect: {
-        !function() {
-            try {
-                throw 0;
-            } catch (e) {
-                console.log(arguments[0]);
-            }
-        }(1);
-    }
-    expect_stdout: "1"
-}
-
-issue_2101: {
-    options = {
-        inline: true,
-    }
-    input: {
-        a = {};
-        console.log(function() {
-            return function() {
-                return this.a;
-            }();
-        }() === function() {
-            return a;
-        }());
-    }
-    expect: {
-        a = {};
-        console.log(function() {
-            return this.a;
-        }() === a);
-    }
-    expect_stdout: "true"
-}
-
-inner_ref: {
-    options = {
-        inline: true,
-        unused: true,
-    }
-    input: {
-        console.log(function(a) {
-            return function() {
-                return a;
-            }();
-        }(1), function(a) {
-            return function(a) {
-                return a;
-            }();
-        }(2));
-    }
-    expect: {
-        console.log(function(a) {
-            return a;
-        }(1), function(a) {
-            return a;
-        }());
-    }
-    expect_stdout: "1 undefined"
-}

test/compress/global_defs.js

@@ -120,7 +120,7 @@ mixed: {
         properties: true,
     }
     input: {
-        var FOO = { BAR: 0 };
+        const FOO = { BAR: 0 };
         console.log(FOO.BAR);
         console.log(++CONFIG.DEBUG);
         console.log(++CONFIG.VALUE);
@@ -130,7 +130,7 @@ mixed: {
         console.log(CONFIG);
     }
     expect: {
-        var FOO = { BAR: 0 };
+        const FOO = { BAR: 0 };
         console.log("moo");
         console.log(++CONFIG.DEBUG);
         console.log(++CONFIG.VALUE);
@@ -160,17 +160,3 @@ issue_1801: {
         console.log(!0);
     }
 }
-
-issue_1986: {
-    options = {
-        global_defs: {
-            "@alert": "console.log",
-        },
-    }
-    input: {
-        alert(42);
-    }
-    expect: {
-        console.log(42);
-    }
-}

test/compress/harmony.js

@@ -0,0 +1,484 @@
+arrow_function_parens: {
+    input: {
+        something && (() => {});
+    }
+    expect_exact: "something&&(()=>{});"
+}
+arrow_function_parens_2: {
+    input: {
+        (() => null)();
+    }
+    expect_exact: "(()=>null)();"
+}
+
+typeof_arrow_functions: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var foo = typeof (x) => null;
+    }
+    expect_exact: "var foo=\"function\";"
+}
+
+classes: {
+    input: {
+        class SomeClass {
+            constructor() {
+            };
+            foo() {};
+        };
+        class NoSemi {
+            constructor(...args) {
+            }
+            foo() {}
+        };
+        class ChildClass extends SomeClass {};
+        var asExpression = class AsExpression {};
+        var nameless = class {};
+    }
+    expect_exact: "class SomeClass{constructor(){}foo(){}}class NoSemi{constructor(...args){}foo(){}}class ChildClass extends SomeClass{}var asExpression=class AsExpression{};var nameless=class{};"
+}
+
+class_statics: {
+    input: {
+        x = class {
+            static staticMethod() {}
+            static get foo() {}
+            static set bar() {}
+            static() { /* "static" can be a method name! */ }
+            get() { /* "get" can be a method name! */ }
+            set() { /* "set" can be a method name! */ }
+        }
+    }
+    expect_exact: "x=class{static staticMethod(){}static get foo(){}static set bar(){}static(){}get(){}set(){}};"
+}
+
+class_name_can_be_mangled: {
+    mangle = { };
+    input: {
+        function x() {
+            class Foo {
+            }
+            var class1 = Foo
+            var class2 = class Bar {}
+        }
+    }
+    expect: {
+        function x() {
+            class a { }
+            var n = a
+            var r = class a {}
+        }
+    }
+}
+
+class_name_can_be_preserved: {
+    mangle = {
+        keep_classnames: true
+    }
+    input: {
+        function x() {
+            (class Baz { });
+            class Foo {};
+        }
+    }
+    expect: {
+        function x() {
+            (class Baz { });
+            class Foo {};
+        }
+    }
+}
+
+classes_can_have_generators: {
+    input: {
+        class Foo {
+            *bar() {}
+            static *baz() {}
+        }
+    }
+    expect: {
+        class Foo {
+            *bar() {}
+            static *baz() {}
+        }
+    }
+}
+
+classes_can_have_computed_generators: {
+    input: {
+        class C4 {
+            *['constructor']() {}
+        }
+    }
+    expect: {
+        class C4 {
+            *['constructor']() {}
+        }
+    }
+}
+
+classes_can_have_computed_static: {
+    input: {
+        class C4 {
+            static ['constructor']() {}
+        }
+    }
+    expect: {
+        class C4 {
+            static ['constructor']() {}
+        }
+    }
+}
+
+class_methods_and_getters_with_keep_quoted_props_enabled: {
+    beautify = {
+        quote_style: 3,
+        keep_quoted_props: true,
+    }
+    input: {
+        class clss {
+            a() {}
+            "b"() {}
+            get c() { return "c"}
+            get "d"() { return "d"}
+            set e(a) { doSomething(a); }
+            set 'f'(a) { doSomething(b); }
+            static g() {}
+            static "h"() {}
+        }
+    }
+    expect_exact: 'class clss{a(){}"b"(){}get c(){return"c"}get"d"(){return"d"}set e(a){doSomething(a)}set\'f\'(a){doSomething(b)}static g(){}static"h"(){}}'
+}
+
+classes_with_expression_as_expand: {
+    input: {
+        class D extends (calls++, C) {}
+    }
+    expect_exact: "class D extends(calls++,C){}"
+}
+
+new_target: {
+    input: {
+        new.target;
+        new.target.name;
+    }
+    expect_exact: "new.target;new.target.name;"
+}
+
+number_literals: {
+    input: {
+        0b1001;
+        0B1001;
+        0o11;
+        0O11;
+    }
+
+    expect: {
+        9;
+        9;
+        9;
+        9;
+    }
+}
+
+import_statement: {
+    input: {
+        import "mod-name";
+        import Foo from "bar";
+        import { Bar, Baz } from 'lel';
+        import Bar, { Foo } from 'lel';
+        import { Bar as kex, Baz as food } from 'lel';
+    }
+    expect_exact: 'import"mod-name";import Foo from"bar";import{Bar,Baz}from"lel";import Bar,{Foo}from"lel";import{Bar as kex,Baz as food}from"lel";'
+}
+
+import_all_statement: {
+    input: {
+        import * from 'lel';
+        import * as Lel from 'lel';
+    }
+    expect_exact: 'import*from"lel";import*as Lel from"lel";'
+}
+
+export_statement: {
+    input: {
+        export default 1;
+        export var foo = 4;
+        export let foo = 6;
+        export const foo = 6;
+        export function foo() {};
+        export class foo { };
+    }
+    expect_exact: "export default 1;export var foo=4;export let foo=6;export const foo=6;export function foo(){};export class foo{};"
+}
+
+export_module_statement: {
+    input: {
+        export * from "a.js";
+        export {A} from "a.js";
+        export {A, B} from "a.js";
+        export {C};
+    }
+    expect_exact: 'export*from"a.js";export{A}from"a.js";export{A,B}from"a.js";export{C};'
+}
+
+import_statement_mangling: {
+    mangle = { toplevel: true };
+    input: {
+        import Foo from "foo";
+        import Bar, {Food} from "lel";
+        import {What as Whatever} from "lel";
+        Foo();
+        Bar();
+        Food();
+        Whatever();
+    }
+    expect: {
+        import l from "foo";
+        import e, {Food as o} from "lel";
+        import {What as f} from "lel";
+        l();
+        e();
+        o();
+        f();
+    }
+}
+
+export_statement_mangling: {
+    mangle = { };
+    input: {
+        export var foo = 6;
+        export function bar() { }
+        export class Baz { }
+        bar(foo, Baz)
+    }
+    expect: {
+        export var foo = 6;
+        export function bar() { }
+        export class Baz { }
+        bar(foo, Baz)
+    }
+}
+
+// https://github.com/mishoo/UglifyJS2/issues/1021
+regression_for_of_const: {
+    input: {
+        for (const x of y) {}
+        for (const x in y) {}
+    }
+    expect: {
+        for (const x of y);for (const x in y);
+    }
+}
+
+// Fabio: My patches accidentally caused a crash whenever
+// there's an extraneous set of parens around an object.
+regression_cannot_destructure: {
+    input: {
+        var x = ({ x : 3 });
+        x(({ x: 3 }));
+    }
+    expect_exact: "var x={x:3};x({x:3});";
+}
+
+regression_cannot_use_of: {
+    input: {
+        function of() {
+        }
+        var of = "is a valid variable name";
+        of = { of: "is ok" };
+        x.of;
+        of: foo()
+    }
+    expect: {
+        function of(){}
+        var of="is a valid variable name";
+        of={of:"is ok"};
+        x.of;
+        foo();  /* Label statement missing? No prob. */
+    }
+}
+
+fat_arrow_as_param: {
+    input: {
+        foo(x => x);
+        foo(x => x, y => y);
+
+        foo(x => (x, x));
+        foo(x => (x, x), y => (y, y));
+    }
+    expect_exact: "foo(x=>x);foo(x=>x,y=>y);foo(x=>(x,x));foo(x=>(x,x),y=>(y,y));"
+}
+
+default_assign: {
+    options = {
+        keep_fargs: false,
+        unused: true,
+    }
+    input: {
+        function f(a, b = 3) {
+            console.log(a);
+        }
+
+        g = ([[] = 123]) => {};
+        h = ([[x, y, z] = [4, 5, 6]] = []) => {};
+
+        function i([[x, y, z] = [4, 5, 6]] = []) {
+            console.log(b);
+        };
+    }
+    expect: {
+        function f(a) {
+            console.log(a);
+        }
+
+        g = ([[] = 123]) => {};
+        h = ([[x, y, z] = [4, 5, 6]] = []) => {};
+
+        function i([[x, y, z] = [4, 5, 6]] = []) {
+            console.log(b);
+        };
+    }
+}
+
+expansion: {
+    options = {
+        keep_fargs: false,
+        unused: true,
+    }
+    input: {
+        function f(a, ...b) {
+            console.log(a);
+        }
+    }
+    expect: {
+        function f(a) {
+            console.log(a);
+        }
+    }
+}
+
+issue_1613: {
+  mangle = { toplevel: true };
+  input: {
+    const name = 1;
+    const foo = {
+      name
+    };
+  }
+  expect_exact: "const n=1;const c={name:n};"
+}
+
+format_methods: {
+    beautify = {
+        beautify: true,
+    }
+    input: {
+        class A extends B {constructor(a){x()} static s(b,c){y()} run(d,e,f){z()}}
+    }
+    expect_exact: [
+        "class A extends B {",
+        "    constructor(a) {",
+        "        x();",
+        "    }",
+        "    static s(b, c) {",
+        "        y();",
+        "    }",
+        "    run(d, e, f) {",
+        "        z();",
+        "    }",
+        "}",
+    ]
+}
+
+issue_1898: {
+    options = {
+    }
+    mangle = {
+    }
+    input: {
+        class Foo {
+            bar() {
+                for (const x of [ 6, 5 ]) {
+                    for (let y of [ 4, 3 ]) {
+                        for (var z of [ 2, 1 ]) {
+                            console.log(x, y, z);
+                        }
+                    }
+                }
+            }
+        }
+        new Foo().bar();
+    }
+    expect: {
+        class Foo {
+            bar() {
+                for (const n of [ 6, 5 ])
+                    for (let r of [ 4, 3 ])
+                        for (var o of [ 2, 1 ])
+                            console.log(n, r, o);
+            }
+        }
+        new Foo().bar();
+    }
+}
+
+issue_1753: {
+    mangle = { safari10: true };
+    input: {
+        class SomeClass {
+            constructor(props) {
+                let pickedSets = [];
+                for (let i = 0; i < 6; i++) {
+                    pickedSets.push({
+                        mainDrawNumbers: [],
+                        extraDrawNumbers: []
+                    });
+                }
+            }
+        }
+    }
+    expect: {
+        class SomeClass {
+            constructor(r) {
+                let a = [];
+                for (let s = 0; s < 6; s++)
+                    a.push({
+                        mainDrawNumbers: [],
+                        extraDrawNumbers: []
+                    });
+            }
+        }
+    }
+}
+
+issue_1753_disable: {
+    mangle = { safari10: false }
+    input: {
+        class SomeClass {
+            constructor(props) {
+                let pickedSets = [];
+                for (let i = 0; i < 6; i++) {
+                    pickedSets.push({
+                        mainDrawNumbers: [],
+                        extraDrawNumbers: []
+                    });
+                }
+            }
+        }
+    }
+    expect: {
+        class SomeClass {
+            constructor(r) {
+                let a = [];
+                for (let r = 0; r < 6; r++)
+                    a.push({
+                        mainDrawNumbers: [],
+                        extraDrawNumbers: []
+                    });
+            }
+        }
+    }
+}

test/compress/hoist.js

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

test/compress/html_comments.js

@@ -53,3 +53,12 @@ html_comment_in_string_literal: {
     }
     expect_exact: 'function f(){return"\\x3c!--HTML--\\x3ecomment in\\x3c!--string literal--\\x3e"}';
 }
+
+html_comment_after_multiline_comment: {
+    input: {
+        var foo; /*
+*/-->   var bar;
+        var foobar;
+    }
+    expect_exact: "var foo;var foobar;"
+}

test/compress/if_return.js

@@ -302,27 +302,3 @@ issue_1437_conditionals: {
         }
     }
 }
-
-issue_512: {
-    options = {
-        conditionals: true,
-        if_return: true,
-        sequences: true,
-        side_effects: true,
-    }
-    input: {
-        function a() {
-            if (b()) {
-                c();
-                return;
-            }
-            throw e;
-        }
-    }
-    expect: {
-        function a() {
-            if (!b()) throw e;
-            c();
-        }
-    }
-}

test/compress/issue-1001.js

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

test/compress/issue-1034.js

@@ -116,137 +116,3 @@ non_hoisted_function_after_return_2b: {
         "WARN: Dropping unreachable code [test/compress/issue-1034.js:101,12]",
     ]
 }
-
-non_hoisted_function_after_return_strict: {
-    options = {
-        hoist_funs: false, dead_code: true, conditionals: true, comparisons: true,
-        evaluate: true, booleans: true, loops: true, unused: true, keep_fargs: true,
-        if_return: true, join_vars: true, cascade: true, side_effects: true
-    }
-    input: {
-        "use strict";
-        function foo(x) {
-            if (x) {
-                return bar();
-                not_called1();
-            } else {
-                return baz();
-                not_called2();
-            }
-            function bar() { return 7; }
-            return not_reached;
-            function UnusedFunction() {}
-            function baz() { return 8; }
-        }
-        console.log(foo(0), foo(1));
-    }
-    expect: {
-        "use strict";
-        function foo(x) {
-            return x ? bar() : baz();
-            function bar() { return 7 }
-            function baz() { return 8 }
-        }
-        console.log(foo(0), foo(1));
-    }
-    expect_stdout: "8 7"
-    expect_warnings: [
-        'WARN: Dropping unreachable code [test/compress/issue-1034.js:131,16]',
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:134,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:137,12]",
-        "WARN: Dropping unused function UnusedFunction [test/compress/issue-1034.js:138,21]"
-    ]
-}
-
-non_hoisted_function_after_return_2a_strict: {
-    options = {
-        hoist_funs: false, dead_code: true, conditionals: true, comparisons: true,
-        evaluate: true, booleans: true, loops: true, unused: true, keep_fargs: true,
-        if_return: true, join_vars: true, cascade: true, side_effects: true,
-        collapse_vars: false, passes: 2, warnings: "verbose"
-    }
-    input: {
-        "use strict";
-        function foo(x) {
-            if (x) {
-                return bar(1);
-                var a = not_called(1);
-            } else {
-                return bar(2);
-                var b = not_called(2);
-            }
-            var c = bar(3);
-            function bar(x) { return 7 - x; }
-            function nope() {}
-            return b || c;
-        }
-        console.log(foo(0), foo(1));
-    }
-    expect: {
-        "use strict";
-        function foo(x) {
-            return bar(x ? 1 : 2);
-            function bar(x) {
-                return 7 - x;
-            }
-        }
-        console.log(foo(0), foo(1));
-    }
-    expect_stdout: "5 6"
-    expect_warnings: [
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:173,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:173,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:176,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:176,16]",
-        "WARN: Dropping unused variable a [test/compress/issue-1034.js:173,20]",
-        "WARN: Dropping unused function nope [test/compress/issue-1034.js:180,21]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:178,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:178,12]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:181,12]",
-        "WARN: Dropping unused variable b [test/compress/issue-1034.js:176,20]",
-        "WARN: Dropping unused variable c [test/compress/issue-1034.js:178,16]",
-    ]
-}
-
-non_hoisted_function_after_return_2b_strict: {
-    options = {
-        hoist_funs: false, dead_code: true, conditionals: true, comparisons: true,
-        evaluate: true, booleans: true, loops: true, unused: true, keep_fargs: true,
-        if_return: true, join_vars: true, cascade: true, side_effects: true,
-        collapse_vars: false
-    }
-    input: {
-        "use strict";
-        function foo(x) {
-            if (x) {
-                return bar(1);
-            } else {
-                return bar(2);
-                var b;
-            }
-            var c = bar(3);
-            function bar(x) {
-                return 7 - x;
-            }
-            return b || c;
-        }
-        console.log(foo(0), foo(1));
-    }
-    expect: {
-        "use strict";
-        function foo(x) {
-            return bar(x ? 1 : 2);
-            function bar(x) { return 7 - x; }
-        }
-        console.log(foo(0), foo(1));
-    }
-    expect_stdout: "5 6"
-    expect_warnings: [
-        // duplicate warnings no longer emitted
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:225,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:225,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:227,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:227,12]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:231,12]",
-    ]
-}

test/compress/issue-1041.js

@@ -1,3 +1,16 @@
+const_declaration: {
+    options = {
+        evaluate: true
+    };
+
+    input: {
+        const goog = goog || {};
+    }
+    expect: {
+        const goog = goog || {};
+    }
+}
+
 const_pragma: {
     options = {
         evaluate: true,

test/compress/issue-1043.js

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

test/compress/issue-1044.js

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

test/compress/issue-1052.js

@@ -1,91 +1,90 @@
 multiple_functions: {
-    options = {
-        hoist_funs: false,
-        if_return: true,
-    }
+    options = { if_return: true, hoist_funs: false };
     input: {
         ( function() {
             if ( !window ) {
                 return;
             }
+
             function f() {}
             function g() {}
         } )();
     }
     expect: {
         ( function() {
+            function f() {}
+            function g() {}
+
             // NOTE: other compression steps will reduce this
             // down to just `window`.
             if ( window );
-            function f() {}
-            function g() {}
         } )();
     }
 }
 
 single_function: {
-    options = {
-        hoist_funs: false,
-        if_return: true,
-    }
+    options = { if_return: true, hoist_funs: false };
     input: {
         ( function() {
             if ( !window ) {
                 return;
             }
+
             function f() {}
         } )();
     }
     expect: {
         ( function() {
-            if ( window );
             function f() {}
+
+            if ( window );
         } )();
     }
 }
 
 deeply_nested: {
-    options = {
-        hoist_funs: false,
-        if_return: true,
-    }
+    options = { if_return: true, hoist_funs: false };
     input: {
         ( function() {
             if ( !window ) {
                 return;
             }
+
             function f() {}
             function g() {}
+
             if ( !document ) {
                 return;
             }
+
             function h() {}
         } )();
     }
     expect: {
         ( function() {
+            function f() {}
+            function g() {}
+
+            function h() {}
+
             // NOTE: other compression steps will reduce this
             // down to just `window`.
             if ( window )
                 if (document);
-            function f() {}
-            function g() {}
-            function h() {}
         } )();
     }
 }
 
 not_hoisted_when_already_nested: {
-    options = {
-        hoist_funs: false,
-        if_return: true,
-    }
+    options = { if_return: true, hoist_funs: false };
     input: {
         ( function() {
             if ( !window ) {
                 return;
             }
+
             if ( foo ) function f() {}
+
         } )();
     }
     expect: {
@@ -95,70 +94,3 @@ not_hoisted_when_already_nested: {
         } )();
     }
 }
-
-defun_if_return: {
-    options = {
-        hoist_funs: false,
-        if_return: true,
-    }
-    input: {
-        function e() {
-            function f() {}
-            if (!window) return;
-            else function g() {}
-            function h() {}
-        }
-    }
-    expect: {
-        function e() {
-            function f() {}
-            if (window) function g() {}
-            function h() {}
-        }
-    }
-}
-
-defun_hoist_funs: {
-    options = {
-        hoist_funs: true,
-        if_return: true,
-    }
-    input: {
-        function e() {
-            function f() {}
-            if (!window) return;
-            else function g() {}
-            function h() {}
-        }
-    }
-    expect: {
-        function e() {
-            function f() {}
-            function g() {}
-            function h() {}
-            if (window);
-        }
-    }
-}
-
-defun_else_if_return: {
-    options = {
-        hoist_funs: false,
-        if_return: true,
-    }
-    input: {
-        function e() {
-            function f() {}
-            if (window) function g() {}
-            else return;
-            function h() {}
-        }
-    }
-    expect: {
-        function e() {
-            function f() {}
-            if (window) function g() {}
-            function h() {}
-        }
-    }
-}

test/compress/issue-1212.js

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

test/compress/issue-1466.js

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

test/compress/issue-1588.js

@@ -85,3 +85,15 @@ unsafe_undefined: {
     }
     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-1770.js

@@ -103,137 +103,3 @@ numeric_literal: {
         "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

@@ -1,7 +1,6 @@
 unary_prefix: {
     options = {
         evaluate: true,
-        inline: true,
         reduce_vars: true,
         unused: true,
     }

test/compress/issue-1943.js

@@ -1,31 +0,0 @@
-operator: {
-    input: {
-        a. //comment
-        typeof
-    }
-    expect_exact: "a.typeof;"
-}
-
-name: {
-    input: {
-        a. //comment
-        b
-    }
-    expect_exact: "a.b;"
-}
-
-keyword: {
-    input: {
-        a. //comment
-        default
-    }
-    expect_exact: "a.default;"
-}
-
-atom: {
-    input: {
-        a. //comment
-        true
-    }
-    expect_exact: "a.true;"
-}

test/compress/issue-203.js

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

test/compress/issue-208.js

@@ -38,7 +38,7 @@ mixed: {
         }
     }
     input: {
-        var ENV = 3;
+        const ENV = 3;
         var FOO = 4;
         f(ENV * 10);
         --FOO;
@@ -49,7 +49,7 @@ mixed: {
         x = DEBUG;
     }
     expect: {
-        var ENV = 3;
+        const ENV = 3;
         var FOO = 4;
         f(10);
         --FOO;
@@ -60,7 +60,7 @@ mixed: {
         x = 0;
     }
     expect_warnings: [
-        'WARN: global_defs ENV redefined [test/compress/issue-208.js:41,12]',
+        '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]',

test/compress/issue-281.js

@@ -1,483 +0,0 @@
-collapse_vars_constants: {
-    options = {
-        collapse_vars: true,
-        evaluate: true,
-        inline: true,
-        reduce_vars: true,
-        unused: true,
-    }
-    input: {
-        function f1(x) {
-            var a = 4, b = x.prop, c = 5, d = sideeffect1(), e = sideeffect2();
-            return b + (function() { return d - a * e - c; })();
-        }
-        function f2(x) {
-            var a = 4, b = x.prop, c = 5, not_used = sideeffect1(), e = sideeffect2();
-            return b + (function() { return -a * e - c; })();
-        }
-    }
-    expect: {
-        function f1(x) {
-            var b = x.prop, d = sideeffect1(), e = sideeffect2();
-            return b + (d - 4 * e - 5);
-        }
-        function f2(x) {
-            var b = x.prop;
-            sideeffect1();
-            return b + (-4 * sideeffect2() - 5);
-        }
-    }
-}
-
-modified: {
-    options = {
-        collapse_vars: true,
-        inline: true,
-        unused: true,
-    }
-    input: {
-        function f5(b) {
-            var a = function() {
-                return b;
-            }();
-            return b++ + a;
-        }
-        console.log(f5(1));
-    }
-    expect: {
-        function f5(b) {
-            var a = b;
-            return b++ + a;
-        }
-        console.log(f5(1));
-    }
-    expect_stdout: "2"
-}
-
-ref_scope: {
-    options = {
-        collapse_vars: true,
-        inline: true,
-        unused: true,
-    }
-    input: {
-        console.log(function() {
-            var a = 1, b = 2, c = 3;
-            var a = c++, b = b /= a;
-            return function() {
-                return a;
-            }() + b;
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var a = 1, b = 2, c = 3;
-            b = b /= a = c++;
-            return a + b;
-        }());
-    }
-    expect_stdout: true
-}
-
-safe_undefined: {
-    options = {
-        conditionals: true,
-        if_return: true,
-        inline: true,
-        unsafe: false,
-        unused: true,
-    }
-    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(a ? b : c ? d : void 0);
-    }
-    expect_stdout: true
-}
-
-negate_iife_3: {
-    options = {
-        conditionals: true,
-        expression: true,
-        inline: true,
-        negate_iife: true,
-    }
-    input: {
-        (function(){ return t })() ? console.log(true) : console.log(false);
-    }
-    expect: {
-        t ? console.log(true) : console.log(false);
-    }
-}
-
-negate_iife_3_off: {
-    options = {
-        conditionals: true,
-        expression: true,
-        inline: true,
-        negate_iife: false,
-    }
-    input: {
-        (function(){ return t })() ? console.log(true) : console.log(false);
-    }
-    expect: {
-        t ? console.log(true) : console.log(false);
-    }
-}
-
-negate_iife_4: {
-    options = {
-        conditionals: true,
-        expression: true,
-        inline: true,
-        negate_iife: true,
-        sequences: true,
-    }
-    input: {
-        (function(){ return t })() ? console.log(true) : console.log(false);
-        (function(){
-            console.log("something");
-        })();
-    }
-    expect: {
-        t ? console.log(true) : console.log(false), void console.log("something");
-    }
-}
-
-negate_iife_5: {
-    options = {
-        conditionals: true,
-        expression: true,
-        inline: true,
-        negate_iife: true,
-        sequences: true,
-    }
-    input: {
-        if ((function(){ return t })()) {
-            foo(true);
-        } else {
-            bar(false);
-        }
-        (function(){
-            console.log("something");
-        })();
-    }
-    expect: {
-        t ? foo(true) : bar(false), void console.log("something");
-    }
-}
-
-negate_iife_5_off: {
-    options = {
-        conditionals: true,
-        expression: true,
-        inline: true,
-        negate_iife: false,
-        sequences: true,
-    };
-    input: {
-        if ((function(){ return t })()) {
-            foo(true);
-        } else {
-            bar(false);
-        }
-        (function(){
-            console.log("something");
-        })();
-    }
-    expect: {
-        t ? foo(true) : bar(false), void console.log("something");
-    }
-}
-
-issue_1254_negate_iife_true: {
-    options = {
-        expression: true,
-        inline: true,
-        negate_iife: true,
-    }
-    input: {
-        (function() {
-            return function() {
-                console.log('test')
-            };
-        })()();
-    }
-    expect_exact: 'void console.log("test");'
-    expect_stdout: true
-}
-
-issue_1254_negate_iife_nested: {
-    options = {
-        expression: true,
-        inline: true,
-        negate_iife: true,
-    }
-    input: {
-        (function() {
-            return function() {
-                console.log('test')
-            };
-        })()()()()();
-    }
-    expect_exact: '(void console.log("test"))()()();'
-}
-
-negate_iife_issue_1073: {
-    options = {
-        conditionals: true,
-        evaluate: true,
-        inline: true,
-        negate_iife: true,
-        reduce_vars: true,
-        sequences: true,
-        unused: true,
-    };
-    input: {
-        new (function(a) {
-            return function Foo() {
-                this.x = a;
-                console.log(this);
-            };
-        }(7))();
-    }
-    expect: {
-        new function() {
-            this.x = 7,
-            console.log(this);
-        }();
-    }
-    expect_stdout: true
-}
-
-issue_1288_side_effects: {
-    options = {
-        conditionals: true,
-        evaluate: true,
-        inline: true,
-        negate_iife: true,
-        reduce_vars: true,
-        side_effects: true,
-        unused: true,
-    };
-    input: {
-        if (w) ;
-        else {
-            (function f() {})();
-        }
-        if (!x) {
-            (function() {
-                x = {};
-            })();
-        }
-        if (y)
-            (function() {})();
-        else
-            (function(z) {
-                return z;
-            })(0);
-    }
-    expect: {
-        w;
-        x || (x = {});
-        y;
-    }
-}
-
-inner_var_for_in_1: {
-    options = {
-        evaluate: true,
-        inline: true,
-        reduce_vars: true,
-    }
-    input: {
-        function f() {
-            var a = 1, b = 2;
-            for (b in (function() {
-                return x(a, b, c);
-            })()) {
-                var c = 3, d = 4;
-                x(a, b, c, d);
-            }
-            x(a, b, c, d);
-        }
-    }
-    expect: {
-        function f() {
-            var a = 1, b = 2;
-            for (b in x(1, b, c)) {
-                var c = 3, d = 4;
-                x(1, b, c, d);
-            }
-            x(1, b, c, d);
-        }
-    }
-}
-
-issue_1595_3: {
-    options = {
-        evaluate: true,
-        inline: true,
-        passes: 2,
-        reduce_vars: true,
-        unused: true,
-    }
-    input: {
-        (function f(a) {
-            return g(a + 1);
-        })(2);
-    }
-    expect: {
-        g(3);
-    }
-}
-
-issue_1758: {
-    options = {
-        inline: true,
-        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 c--, c--, void c.toString();
-        }());
-    }
-    expect_stdout: "undefined"
-}
-wrap_iife: {
-    options = {
-        inline: true,
-        negate_iife: false,
-    }
-    beautify = {
-        wrap_iife: true,
-    }
-    input: {
-        (function() {
-            return function() {
-                console.log('test')
-            };
-        })()();
-    }
-    expect_exact: 'void console.log("test");'
-}
-
-wrap_iife_in_expression: {
-    options = {
-        inline: true,
-        negate_iife: false,
-    }
-    beautify = {
-        wrap_iife: true,
-    }
-    input: {
-        foo = (function () {
-            return bar();
-        })();
-    }
-    expect_exact: 'foo=bar();'
-}
-
-wrap_iife_in_return_call: {
-    options = {
-        inline: true,
-        negate_iife: false,
-    }
-    beautify = {
-        wrap_iife: true,
-    }
-    input: {
-        (function() {
-            return (function() {
-                console.log('test')
-            })();
-        })()();
-    }
-    expect_exact: '(void console.log("test"))();'
-}
-
-pure_annotation: {
-    options = {
-        inline: true,
-        side_effects: true,
-    }
-    input: {
-        /*@__PURE__*/(function() {
-            console.log("hello");
-        }());
-    }
-    expect_exact: ""
-}
-
-drop_fargs: {
-    options = {
-        cascade: true,
-        inline: true,
-        keep_fargs: false,
-        side_effects: true,
-        unused: true,
-    }
-    input: {
-        var a = 1;
-        !function(a_1) {
-            a++;
-        }(a++ + (a && a.var));
-        console.log(a);
-    }
-    expect: {
-        var a = 1;
-        !function() {
-            a++;
-        }(++a && a.var);
-        console.log(a);
-    }
-    expect_stdout: "3"
-}
-
-keep_fargs: {
-    options = {
-        cascade: true,
-        inline: true,
-        keep_fargs: true,
-        side_effects: true,
-        unused: true,
-    }
-    input: {
-        var a = 1;
-        !function(a_1) {
-            a++;
-        }(a++ + (a && a.var));
-        console.log(a);
-    }
-    expect: {
-        var a = 1;
-        !function(a_1) {
-            a++;
-        }(++a && a.var);
-        console.log(a);
-    }
-    expect_stdout: "3"
-}

test/compress/issue-926.js

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

test/compress/join-vars.js

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

test/compress/loops.js

@@ -146,6 +146,50 @@ parse_do_while_without_semicolon: {
     }
 }
 
+
+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,

test/compress/negate-iife.js

@@ -22,8 +22,7 @@ negate_iife_1_off: {
 
 negate_iife_2: {
     options = {
-        inline: true,
-        negate_iife: true,
+        negate_iife: true
     };
     input: {
         (function(){ return {} })().x = 10;
@@ -33,7 +32,6 @@ negate_iife_2: {
 
 negate_iife_2_side_effects: {
     options = {
-        inline: true,
         negate_iife: true,
         side_effects: true,
     }
@@ -60,7 +58,6 @@ negate_iife_3_evaluate: {
     options = {
         conditionals: true,
         evaluate: true,
-        inline: true,
         negate_iife: true,
     }
     input: {
@@ -103,7 +100,6 @@ negate_iife_3_off_evaluate: {
     options = {
         conditionals: true,
         evaluate: true,
-        inline: true,
         negate_iife: false,
     }
     input: {

test/compress/new.js

@@ -82,3 +82,19 @@ new_with_unary_prefix: {
     }
     expect_exact: 'var bar=(+new Date).toString(32);';
 }
+
+new_with_assignement_expression: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var a;
+        new x(a = 5 * 2, b = [1, 2, 3], c = {a: "a", b: "b", cd: "c" + "d"});
+        new y([a, b] = [3, 4]);
+    }
+    expect: {
+        var a;
+        new x(a = 10, b = [1, 2, 3], c = {a: "a", b: "b", cd: "cd"});
+        new y([a, b] = [3, 4]);
+    }
+}

test/compress/node_version.js

@@ -1,38 +0,0 @@
-eval_let_6: {
-    input: {
-        eval("let a;");
-        console.log();
-    }
-    expect: {
-        eval("let a;");
-        console.log();
-    }
-    expect_stdout: ""
-    node_version: ">=6"
-}
-
-eval_let_4: {
-    input: {
-        eval("let a;");
-        console.log();
-    }
-    expect: {
-        eval("let a;");
-        console.log();
-    }
-    expect_stdout: SyntaxError("Block-scoped declarations (let, const, function, class) not yet supported outside strict mode")
-    node_version: "4"
-}
-
-eval_let_0: {
-    input: {
-        eval("let a;");
-        console.log();
-    }
-    expect: {
-        eval("let a;");
-        console.log();
-    }
-    expect_stdout: SyntaxError("Unexpected identifier")
-    node_version: "<=0.12"
-}

test/compress/object.js

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

test/compress/parameters.js

@@ -0,0 +1,180 @@
+arrow_functions: {
+    input: {
+        (a) => b;  // 1 args
+        (a, b) => c;  // n args
+        () => b;  // 0 args
+        (a) => (b) => c;  // func returns func returns func
+        (a) => ((b) => c);  // So these parens are dropped
+        () => (b,c) => d;  // func returns func returns func
+        a=>{return b;}
+        a => 'lel';  // Dropping the parens
+    }
+    expect_exact: "a=>b;(a,b)=>c;()=>b;a=>b=>c;a=>b=>c;()=>(b,c)=>d;a=>b;a=>\"lel\";"
+}
+
+arrow_return: {
+    input: {
+        () => {};
+        () => { return; };
+        a => { return 1; }
+        a => { return -b }
+        a => { return b; var b; }
+        (x, y) => { return x - y; }
+    }
+    expect_exact: "()=>{};()=>{};a=>1;a=>-b;a=>{return b;var b};(x,y)=>x-y;"
+}
+
+regression_arrow_functions_and_hoist: {
+    options = {
+        hoist_vars: true,
+        hoist_funs: true
+    }
+    input: {
+        (a) => b;
+    }
+    expect_exact: "a=>b;"
+}
+
+regression_assign_arrow_functions: {
+    input: {
+        oninstall = e => false;
+        oninstall = () => false;
+    }
+    expect: {
+        oninstall=e=>false;
+        oninstall=()=>false;
+    }
+}
+
+destructuring_arguments_1: {
+    input: {
+        (function ( a ) { });
+        (function ( [ a ] ) { });
+        (function ( [ a, b ] ) { });
+        (function ( [ [ a ] ] ) { });
+        (function ( [ [ a, b ] ] ) { });
+        (function ( [ a, [ b ] ] ) { });
+        (function ( [ [ b ], a ] ) { });
+
+        (function ( { a } ) { });
+        (function ( { a, b } ) { });
+
+        (function ( [ { a } ] ) { });
+        (function ( [ { a, b } ] ) { });
+        (function ( [ a, { b } ] ) { });
+        (function ( [ { b }, a ] ) { });
+
+        ( [ a ] ) => { };
+        ( [ a, b ] ) => { };
+
+        ( { a } ) => { };
+        ( { a, b, c, d, e } ) => { };
+
+        ( [ a ] ) => b;
+        ( [ a, b ] ) => c;
+
+        ( { a } ) => b;
+        ( { a, b } ) => c;
+    }
+    expect: {
+        (function(a){});
+        (function([a]){});
+        (function([a,b]){});
+        (function([[a]]){});
+        (function([[a,b]]){});
+        (function([a,[b]]){});
+        (function([[b],a]){});
+
+        (function({a}){});
+        (function({a,b}){});
+
+        (function([{a}]){});
+        (function([{a,b}]){});
+        (function([a,{b}]){});
+        (function([{b},a]){});
+
+        ([a])=>{};
+        ([a,b])=>{};
+
+        ({a})=>{};
+        ({a,b,c,d,e})=>{};
+
+        ([a])=>b;
+        ([a,b])=>c;
+
+        ({a})=>b;
+        ({a,b})=>c;
+    }
+}
+
+destructuring_arguments_2: {
+    input: {
+        (function([]) {});
+        (function({}) {});
+        (function([,,,,,]) {});
+        (function ([a, {b: c}]) {});
+        (function ([...args]) {});
+        (function ({x,}) {});
+        class a { *method({ [thrower()]: x } = {}) {}};
+        (function(a, b, c, d, [{e: [...f]}]){})(1, 2, 3, 4, [{e: [1, 2, 3]}]);
+    }
+    expect: {
+        (function([]) {});
+        (function({}) {});
+        (function([,,,,,]) {});
+        (function ([a, {b: c}]) {});
+        (function ([...args]) {});
+        (function ({x,}) {});
+        class a { *method({ [thrower()]: x } = {}) {}};
+        (function(a, b, c, d, [{e: [...f]}]){})(1, 2, 3, 4, [{e: [1, 2, 3]}]);
+    }
+}
+
+destructuring_arguments_3: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        function fn3({x: {y: {z: {} = 42}}}) {}
+        const { cover = (function () {}), xCover = (0, function() {})  } = {};
+        let { cover = (function () {}), xCover = (0, function() {})  } = {};
+        var { cover = (function () {}), xCover = (0, function() {})  } = {};
+    }
+    expect_exact: "function fn3({x:{y:{z:{}=42}}}){}const{cover=function(){},xCover=(0,function(){})}={};let{cover=function(){},xCover=(0,function(){})}={};var{cover=function(){},xCover=(0,function(){})}={};"
+}
+
+default_arguments: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        function x(a = 6) { }
+        function x(a = (6 + 5)) { }
+        function x({ foo } = {}, [ bar ] = [ 1 ]) { }
+    }
+    expect_exact: "function x(a=6){}function x(a=6+5){}function x({foo}={},[bar]=[1]){}"
+}
+
+default_values_in_destructurings: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        function x({a=(4), b}) {}
+        function x([b, c=(12)]) {}
+        var { x = (6), y } = x;
+        var [ x, y = (6) ] = x;
+    }
+    expect_exact: "function x({a=4,b}){}function x([b,c=12]){}var{x=6,y}=x;var[x,y=6]=x;"
+}
+
+accept_duplicated_parameters_in_non_strict_without_spread_or_default_assignment: {
+    input: {
+        function a(b, b){}
+        function b({c: test, c: test}){}
+    }
+    expect: {
+        function a(b, b){}
+        function b({c: test, c: test}){}
+    }
+}

test/compress/properties.js

@@ -148,6 +148,7 @@ mangle_unquoted_properties: {
         properties: false
     }
     mangle_props = {
+        builtins: true,
         keep_quoted: true
     }
     beautify = {
@@ -238,6 +239,7 @@ mangle_debug_suffix_keep_quoted: {
         properties: false
     }
     mangle_props = {
+        builtins: true,
         keep_quoted: true,
         debug: "XYZ",
         reserved: []
@@ -555,105 +557,3 @@ native_prototype: {
         "".indexOf.call(e, "bar");
     }
 }
-
-accessor_boolean: {
-    input: {
-        var a = 1;
-        var b = {
-            get true() {
-                return a;
-            },
-            set false(c) {
-                a = c;
-            }
-        };
-        console.log(b.true, b.false = 2, b.true);
-    }
-    expect_exact: 'var a=1;var b={get true(){return a},set false(c){a=c}};console.log(b.true,b.false=2,b.true);'
-    expect_stdout: "1 2 2"
-}
-
-accessor_get_set: {
-    input: {
-        var a = 1;
-        var b = {
-            get set() {
-                return a;
-            },
-            set get(c) {
-                a = c;
-            }
-        };
-        console.log(b.set, b.get = 2, b.set);
-    }
-    expect_exact: 'var a=1;var b={get set(){return a},set get(c){a=c}};console.log(b.set,b.get=2,b.set);'
-    expect_stdout: "1 2 2"
-}
-
-accessor_null_undefined: {
-    input: {
-        var a = 1;
-        var b = {
-            get null() {
-                return a;
-            },
-            set undefined(c) {
-                a = c;
-            }
-        };
-        console.log(b.null, b.undefined = 2, b.null);
-    }
-    expect_exact: 'var a=1;var b={get null(){return a},set undefined(c){a=c}};console.log(b.null,b.undefined=2,b.null);'
-    expect_stdout: "1 2 2"
-}
-
-accessor_number: {
-    input: {
-        var a = 1;
-        var b = {
-            get 42() {
-                return a;
-            },
-            set 42(c) {
-                a = c;
-            }
-        };
-        console.log(b[42], b[42] = 2, b[42]);
-    }
-    expect_exact: 'var a=1;var b={get 42(){return a},set 42(c){a=c}};console.log(b[42],b[42]=2,b[42]);'
-    expect_stdout: "1 2 2"
-}
-
-accessor_string: {
-    input: {
-        var a = 1;
-        var b = {
-            get "a-b"() {
-                return a;
-            },
-            set "a-b"(c) {
-                a = c;
-            }
-        };
-        console.log(b["a-b"], b["a-b"] = 2, b["a-b"]);
-    }
-    expect_exact: 'var a=1;var b={get"a-b"(){return a},set"a-b"(c){a=c}};console.log(b["a-b"],b["a-b"]=2,b["a-b"]);'
-    expect_stdout: "1 2 2"
-}
-
-accessor_this: {
-    input: {
-        var a = 1;
-        var b = {
-            get this() {
-                return a;
-            },
-            set this(c) {
-                a = c;
-            }
-        };
-        console.log(b.this, b.this = 2, b.this);
-    }
-    expect_exact: 'var a=1;var b={get this(){return a},set this(c){a=c}};console.log(b.this,b.this=2,b.this);'
-    expect_stdout: "1 2 2"
-}

test/compress/pure_getters.js

@@ -119,62 +119,3 @@ chained: {
         a.b.c;
     }
 }
-
-impure_getter_1: {
-    options = {
-        pure_getters: "strict",
-        side_effects: true,
-    }
-    input: {
-        ({
-            get a() {
-                console.log(1);
-            },
-            b: 1
-        }).a;
-        ({
-            get a() {
-                console.log(1);
-            },
-            b: 1
-        }).b;
-    }
-    expect: {
-        ({
-            get a() {
-                console.log(1);
-            },
-            b: 1
-        }).a;
-        ({
-            get a() {
-                console.log(1);
-            },
-            b: 1
-        }).b;
-    }
-    expect_stdout: "1"
-}
-
-impure_getter_2: {
-    options = {
-        pure_getters: true,
-        side_effects: true,
-    }
-    input: {
-        // will produce incorrect output because getter is not pure
-        ({
-            get a() {
-                console.log(1);
-            },
-            b: 1
-        }).a;
-        ({
-            get a() {
-                console.log(1);
-            },
-            b: 1
-        }).b;
-    }
-    expect: {}
-}

test/compress/reduce_vars.js

@@ -2,7 +2,6 @@ reduce_vars: {
     options = {
         conditionals  : true,
         evaluate      : true,
-        inline        : true,
         global_defs   : {
             C : 0
         },
@@ -42,20 +41,20 @@ reduce_vars: {
         var A = 1;
         (function() {
             console.log(-3);
-            console.log(A - 5);
+            console.log(-4);
         })();
         (function f1() {
             var a = 2;
-            console.log(a - 5);
+            console.log(-3);
             eval("console.log(a);");
         })();
         (function f2(eval) {
             var a = 2;
-            console.log(a - 5);
+            console.log(-3);
             eval("console.log(a);");
         })(eval);
         "yes";
-        console.log(A + 1);
+        console.log(2);
     }
     expect_stdout: true
 }
@@ -1033,7 +1032,6 @@ defun_inline_2: {
 defun_inline_3: {
     options = {
         evaluate: true,
-        inline: true,
         passes: 2,
         reduce_vars: true,
         side_effects: true,
@@ -1056,7 +1054,6 @@ defun_inline_3: {
 
 defun_call: {
     options = {
-        inline: true,
         reduce_vars: true,
         unused: true,
     }
@@ -1083,7 +1080,6 @@ defun_call: {
 
 defun_redefine: {
     options = {
-        inline: true,
         reduce_vars: true,
         unused: true,
     }
@@ -1116,7 +1112,6 @@ defun_redefine: {
 
 func_inline: {
     options = {
-        inline: true,
         reduce_vars: true,
         unused: true,
     }
@@ -1143,7 +1138,6 @@ func_inline: {
 
 func_modified: {
     options = {
-        inline: true,
         reduce_vars: true,
         unused: true,
     }
@@ -1317,47 +1311,19 @@ iife_func_side_effects: {
         unused: true,
     }
     input: {
-        function x() {
-            console.log("x");
-        }
-        function y() {
-            console.log("y");
-        }
-        function z() {
-            console.log("z");
-        }
         (function(a, b, c) {
-            function y() {
-                console.log("FAIL");
-            }
-            return y + b();
+            return b();
         })(x(), function() {
             return y();
         }, z());
     }
     expect: {
-        function x() {
-            console.log("x");
-        }
-        function y() {
-            console.log("y");
-        }
-        function z() {
-            console.log("z");
-        }
         (function(a, b, c) {
             return function() {
-                console.log("FAIL");
-            } + b();
-        })(x(), function() {
-            return y();
-        }, z());
+                return y();
+            }();
+        })(x(), 0, z());
     }
-    expect_stdout: [
-        "x",
-        "z",
-        "y",
-    ]
 }
 
 issue_1595_1: {
@@ -1721,7 +1687,6 @@ redefine_arguments_1: {
 redefine_arguments_2: {
     options = {
         evaluate: true,
-        inline: true,
         keep_fargs: false,
         reduce_vars: true,
         side_effects: true,
@@ -1758,7 +1723,6 @@ redefine_arguments_2: {
 redefine_arguments_3: {
     options = {
         evaluate: true,
-        inline: true,
         keep_fargs: false,
         passes: 3,
         reduce_vars: true,
@@ -1785,10 +1749,7 @@ redefine_arguments_3: {
         console.log(function() {
             var arguments;
             return typeof arguments;
-        }(), "number", function(x) {
-            var arguments = x;
-            return typeof arguments;
-        }());
+        }(), "number", "undefined");
     }
     expect_stdout: "object number undefined"
 }
@@ -1835,7 +1796,6 @@ redefine_farg_1: {
 redefine_farg_2: {
     options = {
         evaluate: true,
-        inline: true,
         keep_fargs: false,
         reduce_vars: true,
         side_effects: true,
@@ -1872,7 +1832,6 @@ redefine_farg_2: {
 redefine_farg_3: {
     options = {
         evaluate: true,
-        inline: true,
         keep_fargs: false,
         passes: 3,
         reduce_vars: true,
@@ -2228,11 +2187,10 @@ issue_1814_1: {
     options = {
         evaluate: true,
         reduce_vars: true,
-        toplevel: true,
         unused: true,
     }
     input: {
-        var a = 42;
+        const a = 42;
         !function() {
             var b = a;
             !function(a) {
@@ -2241,6 +2199,7 @@ issue_1814_1: {
         }();
     }
     expect: {
+        const a = 42;
         !function() {
             !function(a) {
                 console.log(a++, 42);
@@ -2254,11 +2213,10 @@ issue_1814_2: {
     options = {
         evaluate: true,
         reduce_vars: true,
-        toplevel: true,
         unused: true,
     }
     input: {
-        var a = "32";
+        const a = "32";
         !function() {
             var b = a + 1;
             !function(a) {
@@ -2267,6 +2225,7 @@ issue_1814_2: {
         }();
     }
     expect: {
+        const a = "32";
         !function() {
             !function(a) {
                 console.log(a++, "321");
@@ -2502,76 +2461,3 @@ issue_1865: {
     }
     expect_stdout: true
 }
-
-issue_1922_1: {
-    options = {
-        evaluate: true,
-        reduce_vars: true,
-        unused: true,
-    }
-    input: {
-        console.log(function(a) {
-            arguments[0] = 2;
-            return a;
-        }(1));
-    }
-    expect: {
-        console.log(function(a) {
-            arguments[0] = 2;
-            return a;
-        }(1));
-    }
-    expect_stdout: "2"
-}
-
-issue_1922_2: {
-    options = {
-        evaluate: true,
-        reduce_vars: true,
-        unused: true,
-    }
-    input: {
-        console.log(function() {
-            var a;
-            eval("a = 1");
-            return a;
-        }(1));
-    }
-    expect: {
-        console.log(function() {
-            var a;
-            eval("a = 1");
-            return a;
-        }(1));
-    }
-    expect_stdout: "1"
-}
-
-accessor: {
-    options = {
-        evaluate: true,
-        reduce_vars: true,
-        toplevel: true,
-    }
-    input: {
-        var a = 1;
-        console.log({
-            get a() {
-                a = 2;
-                return a;
-            },
-            b: 1
-        }.b, a);
-    }
-    expect: {
-        var a = 1;
-        console.log({
-            get a() {
-                a = 2;
-                return a;
-            },
-            b: 1
-        }.b, a);
-    }
-    expect_stdout: "1 1"
-}

test/compress/sandbox.js

@@ -1,14 +0,0 @@
-console_log: {
-    input: {
-        console.log("%% %s");
-        console.log("%% %s", "%s");
-    }
-    expect: {
-        console.log("%% %s");
-        console.log("%% %s", "%s");
-    }
-    expect_stdout: [
-        "%% %s",
-        "% %s",
-    ]
-}

test/compress/sequences.js

@@ -711,22 +711,26 @@ issue_27: {
     }
 }
 
-issue_2062: {
+reassign_const: {
     options = {
-        booleans: true,
         cascade: true,
-        conditionals: true,
+        sequences: true,
         side_effects: true,
     }
     input: {
-        var a = 1;
-        if ([ a || a++ + a--, a++ + a--, a && a.var ]);
-        console.log(a);
+        function f() {
+            const a = 1;
+            a++;
+            return a;
+        }
+        console.log(f());
     }
     expect: {
-        var a = 1;
-        a || (a++, a--), a++, --a && a.var;
-        console.log(a);
+        function f() {
+            const a = 1;
+            return a++, a;
+        }
+        console.log(f());
     }
-    expect_stdout: "1"
+    expect_stdout: true
 }

test/compress/string-literal.js

@@ -8,12 +8,3 @@ octal_escape_sequence: {
         var border_check = "\x20\x30\x38\x30\x00\x30\xc0\x30";
     }
 }
-
-issue_1929: {
-    input: {
-        function f(s) {
-            return s.split(/[\\/]/);
-        }
-    }
-    expect_exact: "function f(s){return s.split(/[\\\\/]/)}"
-}

test/compress/super.js

@@ -0,0 +1,9 @@
+
+super_can_be_parsed: {
+    input: {
+        super(1,2);
+        super.meth();
+    }
+    expect_exact: "super(1,2);super.meth();"
+}
+

test/compress/template-string.js

@@ -0,0 +1,402 @@
+template_strings: {
+    beautify = {
+        quote_style: 3
+    }
+    input: {
+        ``;
+        `xx\`x`;
+        `${ foo + 2 }`;
+        ` foo ${ bar + `baz ${ qux }` }`;
+    }
+    expect_exact: "``;`xx\\`x`;`${foo+2}`;` foo ${bar+`baz ${qux}`}`;";
+}
+
+template_string_prefixes: {
+    beautify = {
+        quote_style: 3
+    }
+    input: {
+        String.raw`foo`;
+        foo `bar`;
+    }
+    expect_exact: "String.raw`foo`;foo`bar`;";
+}
+
+template_strings_ascii_only: {
+    beautify = {
+        ascii_only: true,
+        quote_style: 3
+    }
+    input: {
+        var foo = `foo
+        bar
+        ↂωↂ`;
+        var bar = `\``;
+    }
+    expect_exact: "var foo=`foo\\n        bar\\n        \\u2182\\u03c9\\u2182`;var bar=`\\``;"
+}
+
+template_strings_without_ascii_only: {
+    beautify = {
+        quote_style: 3
+    }
+    input: {
+        var foo = `foo
+        bar
+        ↂωↂ`
+    }
+    expect_exact: "var foo=`foo\\n        bar\\n        ↂωↂ`;"
+}
+
+template_string_with_constant_expression: {
+    options = {
+        evaluate: true
+    }
+    beautify = {
+        quote_style: 3
+    }
+    input: {
+        var foo = `${4 + 4} equals 4 + 4`;
+    }
+    expect: {
+        var foo = `8 equals 4 + 4`;
+    }
+}
+
+template_string_with_predefined_constants: {
+    options = {
+        evaluate: true
+    }
+    beautify = {
+        quote_style: 3
+    }
+    input: {
+        var foo = `This is ${undefined}`;
+        var bar = `This is ${NaN}`;
+        var baz = `This is ${null}`;
+        var foofoo = `This is ${Infinity}`;
+        var foobar = "This is ${1/0}";
+        var foobaz = 'This is ${1/0}';
+        var barfoo = "This is ${NaN}";
+        var bazfoo = "This is ${null}";
+        var bazbaz = `This is ${1/0}`;
+        var barbar = `This is ${0/0}`;
+        var barbar = "This is ${0/0}";
+        var barber = 'This is ${0/0}';
+
+        var a = `${4**11}`; // 8 in template vs 7 chars - 4194304
+        var b = `${4**12}`; // 8 in template vs 8 chars - 16777216
+        var c = `${4**14}`; // 8 in template vs 9 chars - 268435456
+    }
+    expect: {
+        var foo = `This is undefined`;
+        var bar = `This is NaN`;
+        var baz = `This is null`;
+        var foofoo = `This is ${1/0}`;
+        var foobar = "This is ${1/0}";
+        var foobaz = 'This is ${1/0}';
+        var barfoo = "This is ${NaN}";
+        var bazfoo = "This is ${null}";
+        var bazbaz = `This is ${1/0}`;
+        var barbar = `This is NaN`;
+        var barbar = "This is ${0/0}";
+        var barber = 'This is ${0/0}';
+
+        var a = `4194304`;
+        var b = `16777216`; // Potential for further concatentation
+        var c = `${4**14}`; // Not worth converting
+    }
+}
+
+template_string_evaluate_with_many_segments: {
+    options = {
+        evaluate: true
+    }
+    beautify = {
+        quote_style: 3
+    }
+    input: {
+        var foo = `Hello ${guest()}, welcome to ${location()}${"."}`;
+        var bar = `${1}${2}${3}${4}${5}${6}${7}${8}${9}${0}`;
+        var baz = `${foobar()}${foobar()}${foobar()}${foobar()}`;
+        var buzz = `${1}${foobar()}${2}${foobar()}${3}${foobar()}`;
+    }
+    expect: {
+        var foo = `Hello ${guest()}, welcome to ${location()}.`;
+        var bar = `1234567890`;
+        var baz = `${foobar()}${foobar()}${foobar()}${foobar()}`;
+        var buzz = `1${foobar()}2${foobar()}3${foobar()}`;
+    }
+}
+
+template_string_with_many_segments: {
+    beautify = {
+        quote_style: 3
+    }
+    input: {
+        var foo = `Hello ${guest()}, welcome to ${location()}${"."}`;
+        var bar = `${1}${2}${3}${4}${5}${6}${7}${8}${9}${0}`;
+        var baz = `${foobar()}${foobar()}${foobar()}${foobar()}`;
+        var buzz = `${1}${foobar()}${2}${foobar()}${3}${foobar()}`;
+    }
+    expect: {
+        var foo = `Hello ${guest()}, welcome to ${location()}${"."}`;
+        var bar = `${1}${2}${3}${4}${5}${6}${7}${8}${9}${0}`;
+        var baz = `${foobar()}${foobar()}${foobar()}${foobar()}`;
+        var buzz = `${1}${foobar()}${2}${foobar()}${3}${foobar()}`;
+    }
+}
+
+template_string_to_normal_string: {
+    options = {
+        evaluate: true
+    }
+    beautify = {
+        quote_style: 0
+    }
+    input: {
+        var foo = `This is ${undefined}`;
+        var bar = "Decimals " + `${1}${2}${3}${4}${5}${6}${7}${8}${9}${0}`;
+    }
+    expect: {
+        var foo = `This is undefined`;
+        var bar = "Decimals 1234567890";
+    }
+}
+
+template_concattenating_string: {
+    options = {
+        evaluate: true
+    }
+    beautify = {
+        quote_style: 3 // Yes, keep quotes
+    }
+    input: {
+        var foo = "Have a nice " + `day. ${`day. ` + `day.`}`;
+        var bar = "Have a nice " + `${day()}`;
+    }
+    expect: {
+        var foo = "Have a nice day. day. day.";
+        var bar = "Have a nice " + `${day()}`;
+    }
+}
+
+evaluate_nested_templates: {
+    options = {
+        evaluate: true
+    }
+    beautify = {
+        quote_style: 0
+    }
+    input: {
+        var baz = `${`${`${`foo`}`}`}`;
+    }
+    expect: {
+        var baz = `foo`;
+    }
+}
+
+enforce_double_quotes: {
+    beautify = {
+        quote_style: 1
+    }
+    input: {
+        var foo = `Hello world`;
+        var bar = `Hello ${'world'}`;
+        var baz = `Hello ${world()}`;
+    }
+    expect: {
+        var foo = `Hello world`;
+        var bar = `Hello ${"world"}`;
+        var baz = `Hello ${world()}`;
+    }
+}
+
+enforce_single_quotes: {
+    beautify = {
+        quote_style: 2
+    }
+    input: {
+        var foo = `Hello world`;
+        var bar = `Hello ${"world"}`;
+        var baz = `Hello ${world()}`;
+    }
+    expect: {
+        var foo = `Hello world`;
+        var bar = `Hello ${'world'}`;
+        var baz = `Hello ${world()}`;
+    }
+}
+
+enforce_double_quotes_and_evaluate: {
+    beautify = {
+        quote_style: 1
+    }
+    options = {
+        evaluate: true
+    }
+    input: {
+        var foo = `Hello world`;
+        var bar = `Hello ${'world'}`;
+        var baz = `Hello ${world()}`;
+    }
+    expect: {
+        var foo = `Hello world`;
+        var bar = `Hello world`;
+        var baz = `Hello ${world()}`;
+    }
+}
+
+enforce_single_quotes_and_evaluate: {
+    beautify = {
+        quote_style: 2
+    }
+    options = {
+        evaluate: true
+    }
+    input: {
+        var foo = `Hello world`;
+        var bar = `Hello ${"world"}`;
+        var baz = `Hello ${world()}`;
+    }
+    expect: {
+        var foo = `Hello world`;
+        var bar = `Hello world`;
+        var baz = `Hello ${world()}`;
+    }
+}
+
+respect_inline_script: {
+    beautify = {
+        inline_script: true,
+        quote_style: 3
+    }
+    input: {
+        var foo = `</script>${content}`;
+        var bar = `<!--`;
+        var baz = `-->`;
+    }
+    expect_exact: "var foo=`<\\/script>${content}`;var bar=`\\x3c!--`;var baz=`--\\x3e`;";
+}
+
+do_not_optimize_tagged_template_1: {
+    beautify = {
+        quote_style: 0
+    }
+    options = {
+        evaluate: true
+    }
+    input: {
+        var foo = tag`Shall not be optimized. ${"But " + "this " + "is " + "fine."}`;
+        var bar = tag`Don't even mind changing my quotes!`;
+    }
+    expect_exact:
+        'var foo=tag`Shall not be optimized. ${"But this is fine."}`;var bar=tag`Don\'t even mind changing my quotes!`;';
+}
+
+do_not_optimize_tagged_template_2: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var foo = tag`test` + " something out";
+    }
+    expect_exact: 'var foo=tag`test`+" something out";';
+}
+
+keep_raw_content_in_tagged_template: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        var foo = tag`\u0020\u{20}\u{00020}\x20\40\040 `;
+    }
+    expect_exact: "var foo=tag`\\u0020\\u{20}\\u{00020}\\x20\\40\\040 `;";
+}
+
+allow_chained_templates: {
+    input: {
+        var foo = tag`a``b``c``d`;
+    }
+    expect: {
+        var foo = tag`a``b``c``d`;
+    }
+}
+
+check_escaped_chars: {
+    input: {
+        var foo = `\u0020\u{20}\u{00020}\x20\40\040 `;
+    }
+    expect_exact: "var foo=`       `;";
+}
+
+escape_dollar_curly: {
+    options = {
+        evaluate: true
+    }
+    input: {
+        console.log(`\$\{ beep \}`)
+        console.log(`${1-0}\${2-0}$\{3-0}${4-0}`)
+        console.log(`$${""}{not an expression}`)
+    }
+    expect_exact: "console.log(`\\${ beep }`);console.log(`1\\${2-0}\\${3-0}4`);console.log(`\\${not an expression}`);"
+}
+
+template_starting_with_newline: {
+    options = {
+        dead_code: true
+    }
+    input: {
+        function foo(e) {
+            return `
+this is a template string!`;
+        };
+    }
+    expect_exact: "function foo(e){return`\\nthis is a template string!`}"
+}
+
+template_with_newline: {
+    options = {
+        dead_code: true
+    }
+    input: {
+        function foo(e) {
+            return `yep,
+this is a template string!`;
+        };
+    }
+    expect_exact: "function foo(e){return`yep,\\nthis is a template string!`}"
+}
+
+template_ending_with_newline: {
+    options = {
+        dead_code: true
+    }
+    input: {
+        function foo(e) {
+            return `this is a template string!
+`;
+        };
+    }
+    expect_exact: "function foo(e){return`this is a template string!\\n`}"
+}
+
+issue_1856: {
+    beautify = {
+        ascii_only: false,
+    }
+    input: {
+        console.log(`\\n\\r\\u2028\\u2029\n\r\u2028\u2029`);
+    }
+    expect_exact: "console.log(`\\\\n\\\\r\\\\u2028\\\\u2029\\n\\r\\u2028\\u2029`);"
+}
+
+issue_1856_ascii_only: {
+    beautify = {
+        ascii_only: true,
+    }
+    input: {
+        console.log(`\\n\\r\\u2028\\u2029\n\r\u2028\u2029`);
+    }
+    expect_exact: "console.log(`\\\\n\\\\r\\\\u2028\\\\u2029\\n\\r\\u2028\\u2029`);"
+}

test/compress/try-catch.js

@@ -0,0 +1,12 @@
+catch_destructuring_with_sequence: {
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        try {
+            throw {};
+        } catch ({xCover = (0, function() {})} ) {
+        }
+    }
+    expect_exact: "try{throw{}}catch({xCover=(0,function(){})}){}"
+}

test/compress/unicode.js

@@ -15,3 +15,106 @@ unicode_parse_variables: {
         var l০ = 3;
     }
 }
+
+unicode_escaped_identifier: {
+    beautify = {ecma: 6}
+    input: {
+        var \u{61} = "foo";
+        var \u{10000} = "bar";
+    }
+    expect_exact: 'var a="foo";var \u{10000}="bar";';
+}
+
+unicode_identifier_ascii_only: {
+    beautify = {ascii_only: true, ecma: 6}
+    input: {
+        var \u{0061} = "hi";
+        var bar = "h\u{0065}llo";
+        var \u{10000} = "testing \u{101111}";
+    }
+    expect_exact: 'var a="hi";var bar="hello";var \\u{10000}="testing \\u{101111}";'
+}
+
+unicode_string_literals: {
+    beautify = {ascii_only: true, ecma: 6}
+    input: {
+        var a = "6 length unicode character: \u{101111}";
+    }
+    expect_exact: 'var a="6 length unicode character: \\u{101111}";'
+}
+
+// Don't escape identifiers below es6 (or in this case double escaped in expect_exact)
+unicode_output_es5_surrogates: {
+    beautify = {ascii_only: true, ecma: 5}
+    input: {
+        var \u{10000} = "6 length unicode character: \u{10FFFF}";
+    }
+    expect_exact: 'var \u{10000}="6 length unicode character: \\udbff\\udfff";'
+}
+
+check_escape_style: {
+    beautify = {ascii_only: true, ecma: 6}
+    input: {
+        var a = "\x01";
+        var \ua0081 = "\x10"; // \u0081 only in ID_Continue
+        var \u0100 = "\u0100";
+        var \u1000 = "\u1000";
+        var \u{10000} = "\u{10000}";
+        var \u{2f800} = "\u{100000}";
+    }
+    expect_exact: 'var a="\\x01";var \\ua0081="\\x10";var \\u0100="\\u0100";var \\u1000="\\u1000";var \\u{10000}="\\u{10000}";var \\u{2f800}="\\u{100000}";'
+}
+
+// Don't escape identifiers below es6, no escaped identifiers support and no \u{} syntax
+check_escape_style_es5: {
+    beautify = {ascii_only: true, ecma: 5}
+    input: {
+        var a = "\x01";
+        var \ua0081 = "\x10"; // \u0081 only in ID_Continue
+        var \u0100 = "\u0100";
+        var \u1000 = "\u1000";
+        var \u{10000} = "\u{10000}"; // Identifier won't be escaped in es 5.1
+        var \u{2f800} = "\u{100000}"; // Same
+    }
+    expect_exact: 'var a="\\x01";var \\ua0081="\\x10";var \\u0100="\\u0100";var \\u1000="\\u1000";var \ud800\udc00="\\ud800\\udc00";var \ud87e\udc00="\\udbc0\\udc00";'
+}
+
+ID_continue_with_surrogate_pair: {
+    beautify = {ascii_only: true, ecma: 6}
+    input: {
+        var \u{2f800}\u{2f800}\u{2f800}\u{2f800} = "\u{100000}\u{100000}\u{100000}\u{100000}\u{100000}";
+    }
+    expect_exact: 'var \\u{2f800}\\u{2f800}\\u{2f800}\\u{2f800}="\\u{100000}\\u{100000}\\u{100000}\\u{100000}\\u{100000}";'
+}
+
+escape_non_escaped_identifier: {
+    beautify = {ascii_only: true, ecma: 6}
+    input: {
+        var µþ = "µþ";
+    }
+    expect_exact: 'var \\u00b5\\u00fe="\\xb5\\xfe";'
+}
+
+non_escape_2_non_escape: {
+    beautify = {ascii_only: false, ecma: 6}
+    input: {
+        var µþ = "µþ";
+    }
+    expect_exact: 'var µþ="µþ";'
+}
+
+non_escape_2_half_escape1: {
+    beautify = {ascii_only: false, ascii_identifiers: true, ecma: 6}
+    input: {
+        var µþ = "µþ";
+    }
+    expect_exact: 'var \\u00b5\\u00fe="µþ";'
+}
+
+non_escape_2_half_escape2: {
+    beautify = {ascii_only: true, ascii_identifiers: false, ecma: 6}
+    input: {
+        var µþ = "µþ";
+    }
+    expect_exact: 'var µþ="\\xb5\\xfe";'
+}

test/compress/yield.js

@@ -0,0 +1,192 @@
+generators: {
+    input: {
+        function* fn() {};
+    }
+    expect_exact: "function*fn(){}"
+}
+
+generators_yield: {
+    input: {
+      function* fn() {
+        yield remote();
+      }
+    }
+    expect_exact: "function*fn(){yield remote()}"
+}
+
+generators_yield_assign: {
+    input: {
+      function* fn() {
+          var x = {};
+          x.prop = yield 5;
+      }
+    }
+    expect_exact: "function*fn(){var x={};x.prop=yield 5}"
+}
+
+generator_yield_undefined: {
+    input: {
+        function* fn() {
+            yield;
+        }
+    }
+    expect_exact: "function*fn(){yield}"
+}
+
+yield_optimize_expression: {
+    options = {
+    }
+    input: {
+        function* f1() { yield; }
+        function* f2() { yield undefined; }
+        function* f3() { yield null; }
+        function* f4() { yield* undefined; }
+    }
+    expect: {
+        function* f1() { yield }
+        function* f2() { yield; }
+        function* f3() { yield null; }
+        function* f4() { yield* void 0; }
+    }
+}
+
+yield_statements: {
+    input: {
+        function* fn() {
+            var a = (yield 1) + (yield 2);
+            var b = (yield 3) === (yield 4);
+            var c = (yield 5) << (yield 6);
+            var d = yield 7;
+            var e = (yield 8) ? yield 9 : yield 10;
+            var f = -(yield 11);
+        }
+    }
+    expect_exact: "function*fn(){var a=(yield 1)+(yield 2);var b=(yield 3)===(yield 4);var c=(yield 5)<<(yield 6);var d=yield 7;var e=(yield 8)?yield 9:yield 10;var f=-(yield 11)}"
+}
+
+yield_as_identifier_in_function_in_generator: {
+    input: {
+        var g = function*() {
+            function h() {
+                yield = 1;
+            }
+        };
+    }
+    expect: {
+        var g = function*() {
+            function h() {
+                yield = 1;
+            }
+        };
+    }
+}
+
+yield_before_punctuators: {
+    input: {
+        iter = (function*() {
+            assignmentResult = [ x = yield ] = value;
+        })();
+        function* g1() { (yield) }
+        function* g2() { [yield] }
+        function* g3() { return {yield} } // Added return to avoid {} drop
+        function* g4() { yield, yield; }
+        function* g5() { (yield) ? yield : yield; }
+    }
+    expect: {
+        iter = (function*() {
+            assignmentResult = [ x = yield ] = value;
+        })();
+        function* g1() { (yield) }
+        function* g2() { [yield] }
+        function* g3() { return {yield} }
+        function* g4() { yield, yield; }
+        function* g5() { (yield) ? yield : yield; }
+    }
+}
+
+yield_as_identifier_outside_strict_mode: {
+    input: {
+        import yield from "bar";
+        yield = 123;
+        while (true) {
+            yield:
+            for(;;) break yield;
+
+            foo();
+        }
+        while (true)
+            yield: for(;;) continue yield;
+        function yield(){}
+        function foo(...yield){}
+        try { new Error("") } catch (yield) {}
+        var yield = "foo";
+    }
+    expect: {
+        import yield from "bar";
+        yield = 123;
+        while (true) {
+            yield:
+            for(;;) break yield;
+
+            foo();
+        }
+        while (true)
+            yield: for(;;) continue yield;
+        function yield(){}
+        function foo(...yield){}
+        try { new Error("") } catch (yield) {}
+        var yield = "foo";
+    }
+}
+
+empty_generator_as_parameter_with_side_effects: {
+    options = {
+        side_effects: true
+    }
+    input: {
+        var GeneratorPrototype = Object.getPrototypeOf(
+          Object.getPrototypeOf(function*() {}())
+        );
+        evaluate(GeneratorPrototype);
+    }
+    expect_exact: "var GeneratorPrototype=Object.getPrototypeOf(Object.getPrototypeOf(function*(){}()));evaluate(GeneratorPrototype);"
+}
+
+empty_generator_as_parameter_without_side_effects: {
+    options = {
+        side_effects: false
+    }
+    input: {
+        var GeneratorPrototype = Object.getPrototypeOf(
+          Object.getPrototypeOf(function*() {}())
+        );
+        evaluate(GeneratorPrototype);
+    }
+    expect_exact: "var GeneratorPrototype=Object.getPrototypeOf(Object.getPrototypeOf(function*(){}()));evaluate(GeneratorPrototype);"
+}
+
+yield_dot: {
+    options = {
+    }
+    input: {
+        function* foo(){
+            yield x.foo;
+            (yield x).foo;
+            yield (yield obj.foo()).bar();
+        }
+    }
+    expect_exact: "function*foo(){yield x.foo;(yield x).foo;yield(yield obj.foo()).bar()}"
+}
+
+yield_sub: {
+    options = {
+    }
+    input: {
+        function* foo(){
+            yield x['foo'];
+            (yield x)['foo'];
+            yield (yield obj.foo())['bar']();
+        }
+    }
+    expect_exact: 'function*foo(){yield x["foo"];(yield x)["foo"];yield(yield obj.foo())["bar"]()}'
+}

test/fetch.js

@@ -1,31 +0,0 @@
-var fs = require("fs");
-var path = require("path");
-
-try {
-    fs.mkdirSync("./tmp");
-} catch (e) {
-    if (e.code != "EEXIST") throw e;
-}
-
-function local(url) {
-    return path.join("./tmp", encodeURIComponent(url));
-}
-
-function read(url) {
-    return fs.createReadStream(local(url));
-}
-
-module.exports = function(url, callback) {
-    var result = read(url);
-    result.on("error", function(e) {
-        if (e.code != "ENOENT") return callback(e);
-        require(url.slice(0, url.indexOf(":"))).get(url, function(res) {
-            if (res.statusCode !== 200) return callback(res);
-            res.pipe(fs.createWriteStream(local(url)).on("close", function() {
-                callback(null, read(url));
-            }));
-        });
-    }).on("open", function() {
-        callback(null, result);
-    });
-};

test/input/invalid/const.js

@@ -0,0 +1,8 @@
+function f() {
+    const a;
+}
+
+function g() {
+    "use strict";
+    const a;
+}

test/input/invalid/else.js

@@ -1 +0,0 @@
-if (0) else 1;

test/input/invalid/return.js

@@ -1 +0,0 @@
-return 42;

test/input/issue-2082/sample.js

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

test/input/issue-2082/sample.js.map

@@ -1 +0,0 @@
-{"version": 3,"sources": ["index.js"],"mappings": ";"}

test/input/issue-505/input.js

@@ -1,5 +0,0 @@
-function test(callback) {
-    'aaaaaaaaaaaaaaaa';
-    callback(err, data);
-    callback(err, data);
-}

test/input/issue-505/output.js

@@ -1,5 +0,0 @@
-function test(a){
-"aaaaaaaaaaaaaaaa"
-;a(err,data),a(err,data)
-}
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsidGVzdCIsImNhbGxiYWNrIiwiZXJyIiwiZGF0YSJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0EsS0FBS0M7QUFDVjtDQUNBQSxFQUFTQyxJQUFLQyxNQUNkRixFQUFTQyxJQUFLQyJ9

test/input/issue-520/output.js

@@ -1,2 +1,2 @@
 new function(){console.log(3)};
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUErQyxJQUFyQyxXQUFnQkEsUUFBUUMsSUFBSSIsInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl19
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUErQyxHQUFyQyxZQUFnQkEsUUFBUUMsSUFBSSIsInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl19

test/jetstream.js

@@ -3,7 +3,7 @@
 
 "use strict";
 
-var site = "http://browserbench.org/JetStream";
+var site = "http://browserbench.org/JetStream/";
 if (typeof phantom == "undefined") {
     // workaround for tty output truncation upon process.exit()
     [process.stdout, process.stderr].forEach(function(stream){
@@ -11,69 +11,45 @@ if (typeof phantom == "undefined") {
             stream._handle.setBlocking(true);
     });
     var args = process.argv.slice(2);
-    var debug = args.indexOf("--debug");
-    if (debug >= 0) {
-        args.splice(debug, 1);
-        debug = true;
-    } else {
-        debug = false;
-    }
     if (!args.length) {
-        args.push("-mcb", "beautify=false,webkit");
+        args.push("-mc");
     }
-    args.push("--timings");
+    args.push("--stats");
     var child_process = require("child_process");
-    var fetch = require("./fetch");
+    try {
+        require("phantomjs-prebuilt");
+    } catch(e) {
+        child_process.execSync("npm install phantomjs-prebuilt@2.1.14");
+    }
     var http = require("http");
     var server = http.createServer(function(request, response) {
         request.resume();
-        var url = site + request.url;
-        fetch(url, function(err, res) {
-            if (err) throw err;
-            response.writeHead(200, {
-                "Content-Type": {
-                    css: "text/css",
-                    js: "application/javascript",
-                    png: "image/png"
-                }[url.slice(url.lastIndexOf(".") + 1)] || "text/html; charset=utf-8"
-            });
-            if (/\.js$/.test(url)) {
-                var stderr = "";
-                var uglifyjs = child_process.fork("bin/uglifyjs", args, {
-                    silent: true
-                }).on("exit", function(code) {
-                    console.log("uglifyjs", url.slice(site.length + 1), args.join(" "));
-                    console.log(stderr);
-                    if (code) throw new Error("uglifyjs failed with code " + code);
-                });
-                uglifyjs.stderr.on("data", function(data) {
-                    stderr += data;
-                }).setEncoding("utf8");
-                uglifyjs.stdout.pipe(response);
-                res.pipe(uglifyjs.stdin);
-            } else {
-                res.pipe(response);
-            }
+        var url = decodeURIComponent(request.url.slice(1));
+        var stderr = "";
+        var uglifyjs = child_process.fork("bin/uglifyjs", args, {
+            silent: true
+        }).on("exit", function(code) {
+            console.log("uglifyjs", url.indexOf(site) == 0 ? url.slice(site.length) : url, args.join(" "));
+            console.log(stderr);
+            if (code) throw new Error("uglifyjs failed with code " + code);
+        });
+        uglifyjs.stderr.on("data", function(data) {
+            stderr += data;
+        }).setEncoding("utf8");
+        uglifyjs.stdout.pipe(response);
+        http.get(url, function(res) {
+            res.pipe(uglifyjs.stdin);
+        });
+    }).listen().on("listening", function() {
+        var phantomjs = require("phantomjs-prebuilt");
+        var program = phantomjs.exec(process.argv[1], server.address().port);
+        program.stdout.pipe(process.stdout);
+        program.stderr.pipe(process.stderr);
+        program.on("exit", function(code) {
+            server.close();
+            if (code) throw new Error("JetStream failed!");
+            console.log("JetStream completed successfully.");
         });
-    }).listen();
-    server.on("listening", function() {
-        var port = server.address().port;
-        if (debug) {
-            console.log("http://localhost:" + port + "/");
-        } else {
-            child_process.exec("npm install phantomjs-prebuilt@2.1.14 --no-save", function(error) {
-                if (error) throw error;
-                var program = require("phantomjs-prebuilt").exec(process.argv[1], port);
-                program.stdout.pipe(process.stdout);
-                program.stderr.pipe(process.stderr);
-                program.on("exit", function(code) {
-                    server.close();
-                    if (code) throw new Error("JetStream failed!");
-                    console.log("JetStream completed successfully.");
-                    process.exit(0);
-                });
-            });
-        }
     });
     server.timeout = 0;
 } else {
@@ -87,6 +63,10 @@ if (typeof phantom == "undefined") {
         phantom.exit(1);
     };
     var url = "http://localhost:" + require("system").args[1] + "/";
+    page.onResourceRequested = function(requestData, networkRequest) {
+        if (/\.js$/.test(requestData.url))
+            networkRequest.changeUrl(url + encodeURIComponent(requestData.url));
+    }
     page.onConsoleMessage = function(msg) {
         if (/Error:/i.test(msg)) {
             console.error(msg);
@@ -97,8 +77,8 @@ if (typeof phantom == "undefined") {
             phantom.exit();
         }
     };
-    page.open(url, function(status) {
-        if (status != "success") phantom.exit(1);
+    page.open(site, function(status) {
+        if (status != "success") phantomjs.exit(1);
         page.evaluate(function() {
             JetStream.switchToQuick();
             JetStream.start();

test/mocha/accessorTokens-1492.js

@@ -16,8 +16,8 @@ describe("Accessor tokens", function() {
                 assert.equal(node.start.pos, 12);
                 assert.equal(node.end.endpos, 46);
 
-                assert(node.key instanceof UglifyJS.AST_SymbolAccessor);
-                assert.equal(node.key.start.pos, 16);
+                assert(node.key instanceof UglifyJS.AST_SymbolMethod);
+                assert.equal(node.key.start.pos, 12);
                 assert.equal(node.key.end.endpos, 22);
 
                 assert(node.value instanceof UglifyJS.AST_Accessor);

test/mocha/arguments.js

@@ -27,4 +27,253 @@ describe("arguments", function() {
         assert.strictEqual(ast.body[0].body[0].uses_arguments, true);
         assert.strictEqual(ast.body[0].body[0].body[0].uses_arguments, false);
     });
-});
+
+    it("Should parse a function containing default assignment correctly", function() {
+        var ast = UglifyJS.parse("function foo(a = 123) {}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // First argument
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_DefaultAssign);
+        assert(ast.body[0].argnames[0].left instanceof UglifyJS.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].argnames[0].operator, "=");
+        assert(ast.body[0].argnames[0].right instanceof UglifyJS.AST_Number);
+
+        ast = UglifyJS.parse("function foo(a = a) {}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // First argument
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_DefaultAssign);
+        assert(ast.body[0].argnames[0].left instanceof UglifyJS.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].argnames[0].operator, "=");
+        assert(ast.body[0].argnames[0].right instanceof UglifyJS.AST_SymbolRef);
+    });
+
+    it("Should parse a function containing default assignments in destructuring correctly", function() {
+        var ast = UglifyJS.parse("function foo([a = 123]) {}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // First argument
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].is_array, true);
+        assert.strictEqual(ast.body[0].argnames[0].names.length, 1);
+        assert(ast.body[0].argnames[0].names[0] instanceof UglifyJS.AST_DefaultAssign);
+        assert(ast.body[0].argnames[0].names[0].left instanceof UglifyJS.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].argnames[0].names[0].operator, "=");
+        assert(ast.body[0].argnames[0].names[0].right instanceof UglifyJS.AST_Number);
+
+
+        ast = UglifyJS.parse("function foo({a = 123}) {}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // First argument
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].is_array, false);
+        assert.strictEqual(ast.body[0].argnames[0].names.length, 1);
+        assert(ast.body[0].argnames[0].names[0] instanceof UglifyJS.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].argnames[0].names[0].key, "a");
+
+        // Property a of first argument
+        assert(ast.body[0].argnames[0].names[0].value instanceof UglifyJS.AST_DefaultAssign);
+        assert(ast.body[0].argnames[0].names[0].value.left instanceof UglifyJS.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].argnames[0].names[0].value.operator, "=");
+        assert(ast.body[0].argnames[0].names[0].value.right instanceof UglifyJS.AST_Number);
+
+
+        ast = UglifyJS.parse("function foo({a: a = 123}) {}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // First argument
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].is_array, false);
+        assert.strictEqual(ast.body[0].argnames[0].names.length, 1);
+
+        // Content destructuring of first argument
+        assert(ast.body[0].argnames[0].names[0] instanceof UglifyJS.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].argnames[0].names[0].key, "a");
+        assert(ast.body[0].argnames[0].names[0].value instanceof UglifyJS.AST_DefaultAssign);
+
+        // Property a of first argument
+        assert(ast.body[0].argnames[0].names[0].value instanceof UglifyJS.AST_DefaultAssign);
+        assert(ast.body[0].argnames[0].names[0].value.left instanceof UglifyJS.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].argnames[0].names[0].value.operator, "=");
+        assert(ast.body[0].argnames[0].names[0].value.right instanceof UglifyJS.AST_Number);
+    });
+
+    it("Should parse a function containing default assignments in complex destructuring correctly", function() {
+        var ast = UglifyJS.parse("function foo([a, [b = 123]]){}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // Check first argument
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].is_array, true);
+        assert.strictEqual(ast.body[0].argnames[0].names.length, 2);
+
+        // Check whole destructuring structure of first argument
+        assert(ast.body[0].argnames[0].names[0] instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[0].names[1] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].names[1].is_array, true);
+
+        // Check content of second destructuring element (which is the nested destructuring pattern)
+        assert(ast.body[0].argnames[0].names[1].names[0] instanceof UglifyJS.AST_DefaultAssign);
+        assert(ast.body[0].argnames[0].names[1].names[0].left instanceof UglifyJS.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].argnames[0].names[1].names[0].operator, "=");
+        assert(ast.body[0].argnames[0].names[1].names[0].right instanceof UglifyJS.AST_Number);
+
+
+        ast = UglifyJS.parse("function foo([a, {b: c = 123}]){}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // Check first argument
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].is_array, true);
+        assert.strictEqual(ast.body[0].argnames[0].names.length, 2);
+
+        // Check whole destructuring structure of first argument
+        assert(ast.body[0].argnames[0].names[0] instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[0].names[1] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].names[1].is_array, false);
+
+        // Check content of second destructuring element (which is the nested destructuring pattern)
+        assert(ast.body[0].argnames[0].names[1].names[0] instanceof UglifyJS.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].argnames[0].names[1].names[0].key, "b");
+        assert(ast.body[0].argnames[0].names[1].names[0].value instanceof UglifyJS.AST_DefaultAssign);
+
+        // Property b of second argument
+        assert(ast.body[0].argnames[0].names[1].names[0].value instanceof UglifyJS.AST_DefaultAssign);
+        assert(ast.body[0].argnames[0].names[1].names[0].value.left instanceof UglifyJS.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].argnames[0].names[1].names[0].value.operator, "=");
+        assert(ast.body[0].argnames[0].names[1].names[0].value.right instanceof UglifyJS.AST_Number);
+
+
+        ast = UglifyJS.parse("function foo({a, b: {b = 123}}){}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // Check first argument
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].is_array, false);
+        assert.strictEqual(ast.body[0].argnames[0].names.length, 2);
+
+        // Check whole destructuring structure of first argument
+        assert(ast.body[0].argnames[0].names[0] instanceof UglifyJS.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].argnames[0].names[0].key, "a");
+        assert(ast.body[0].argnames[0].names[0].value instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[0].names[1] instanceof UglifyJS.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].argnames[0].names[1].key, "b");
+        assert(ast.body[0].argnames[0].names[1].value instanceof UglifyJS.AST_Destructuring);
+
+        // Check content of nested destructuring in first parameter
+        var content = ast.body[0].argnames[0].names[1].value
+        assert.strictEqual(content.is_array, false);
+        assert.strictEqual(content.names.length, 1);
+        assert(content.names[0] instanceof UglifyJS.AST_ObjectKeyVal);
+        assert.strictEqual(content.names[0].key, "b");
+        assert(content.names[0].value instanceof UglifyJS.AST_DefaultAssign);
+        assert(content.names[0].value.left instanceof UglifyJS.AST_SymbolFunarg);
+        assert.strictEqual(content.names[0].value.operator, "=");
+        assert(content.names[0].value.right instanceof UglifyJS.AST_Number);
+
+
+        ast = UglifyJS.parse("function foo({a: {b = 123}}){}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // Check first argument
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].is_array, false);
+        assert.strictEqual(ast.body[0].argnames[0].names.length, 1);
+
+        // Check whole destructuring structure of first argument
+        assert(ast.body[0].argnames[0].names[0] instanceof UglifyJS.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].argnames[0].names[0].key, "a");
+        assert(ast.body[0].argnames[0].names[0].value instanceof UglifyJS.AST_Destructuring);
+
+        // Check content of nested destructuring
+        content = ast.body[0].argnames[0].names[0].value
+        assert.strictEqual(content.is_array, false);
+        assert.strictEqual(content.names.length, 1);
+        assert(content.names[0] instanceof UglifyJS.AST_ObjectKeyVal);
+        assert.strictEqual(content.names[0].key, "b");
+        assert(content.names[0].value instanceof UglifyJS.AST_DefaultAssign);
+        assert(content.names[0].value.left instanceof UglifyJS.AST_SymbolFunarg);
+        assert.strictEqual(content.names[0].value.operator, "=");
+        assert(content.names[0].value.right instanceof UglifyJS.AST_Number);
+    });
+
+    it("Should parse spread correctly", function() {
+        var ast = UglifyJS.parse("function foo(a, b, ...c){}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 3);
+
+        // Check parameters
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[1] instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[2] instanceof UglifyJS.AST_Expansion);
+        assert(ast.body[0].argnames[2].expression instanceof UglifyJS.AST_SymbolFunarg);
+
+
+        ast = UglifyJS.parse("function foo([a, b, ...c]){}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // Check first parameter
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].is_array, true);
+
+        // Check content first parameter
+        assert(ast.body[0].argnames[0].names[0] instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[0].names[1] instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[0].names[2] instanceof UglifyJS.AST_Expansion);
+        assert(ast.body[0].argnames[0].names[2].expression instanceof UglifyJS.AST_SymbolFunarg);
+
+
+        ast = UglifyJS.parse("function foo([a, b, [c, ...d]]){}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // Check first parameter
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].is_array, true);
+
+        // Check content outer destructuring array
+        assert(ast.body[0].argnames[0].names[0] instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[0].names[1] instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[0].names[2] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].names[2].is_array, true);
+
+        // Check content nested destructuring array
+        assert.strictEqual(ast.body[0].argnames[0].names[2].names.length, 2);
+        assert(ast.body[0].argnames[0].names[2].names[0] instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[0].names[2].names[1] instanceof UglifyJS.AST_Expansion);
+        assert(ast.body[0].argnames[0].names[2].names[1].expression instanceof UglifyJS.AST_SymbolFunarg);
+
+
+        ast = UglifyJS.parse("function foo({a: [b, ...c]}){}");
+        assert(ast.body[0] instanceof UglifyJS.AST_Defun);
+        assert.strictEqual(ast.body[0].argnames.length, 1);
+
+        // Check first parameter
+        assert(ast.body[0].argnames[0] instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].is_array, false);
+
+        // Check outer destructuring object
+        assert.strictEqual(ast.body[0].argnames[0].names.length, 1);
+        assert(ast.body[0].argnames[0].names[0] instanceof UglifyJS.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].argnames[0].names[0].key, "a");
+        assert(ast.body[0].argnames[0].names[0].value instanceof UglifyJS.AST_Destructuring);
+        assert.strictEqual(ast.body[0].argnames[0].names[0].value.is_array, true);
+
+        // Check content nested destructuring array
+        assert.strictEqual(ast.body[0].argnames[0].names[0].value.names.length, 2);
+        assert(ast.body[0].argnames[0].names[0].value.names[0] instanceof UglifyJS.AST_SymbolFunarg);
+        assert(ast.body[0].argnames[0].names[0].value.names[1] instanceof UglifyJS.AST_Expansion);
+        assert(ast.body[0].argnames[0].names[0].value.names[1].expression instanceof UglifyJS.AST_SymbolFunarg);
+    });
+});

test/mocha/arrow.js

@@ -0,0 +1,402 @@
+var assert = require("assert");
+var uglify = require("../node");
+
+describe("Arrow functions", function() {
+    it("Should not accept spread tokens on non-last parameters or without arguments parentheses", function() {
+        var tests = [
+            "var a = ...a => {return a.join()}",
+            "var b = (a, ...b, c) => { return a + b.join() + c}",
+            "var c = (...a, b) => a.join()"
+        ];
+        var test = function(code) {
+            return function() {
+                uglify.parse(code);
+            }
+        }
+        var error = function(e) {
+            return e instanceof uglify.JS_Parse_Error &&
+                e.message === "Unexpected token: expand (...)";
+        }
+
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error);
+        }
+    });
+    it("Should not accept holes in object binding patterns, while still allowing a trailing elision", function() {
+        var tests = [
+            "f = ({, , ...x} = [1, 2]) => {};"
+        ];
+        var test = function(code) {
+            return function() {
+                uglify.parse(code);
+            }
+        }
+        var error = function(e) {
+            return e instanceof uglify.JS_Parse_Error &&
+                e.message === "Unexpected token: punc (,)";
+        }
+
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error);
+        }
+    });
+    it("Should not accept newlines before arrow token", function() {
+        var tests = [
+            "f = foo\n=> 'foo';",
+            "f = (foo, bar)\n=> 'foo';",
+            "f = ()\n=> 'foo';",
+            "foo((bar)\n=>'baz';);"
+        ];
+        var test = function(code) {
+            return function() {
+                uglify.parse(code);
+            }
+        }
+        var error = function(e) {
+            return e instanceof uglify.JS_Parse_Error &&
+                e.message === "Unexpected newline before arrow (=>)";
+        }
+
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error);
+        }
+    });
+    it("Should not accept arrow functions in the middle or end of an expression", function() {
+        var tests = [
+            "typeof x => 0",
+            "0 + x => 0"
+        ];
+        var test = function(code) {
+            return function() {
+                uglify.parse(code);
+            }
+        }
+        var error = function(e) {
+            return e instanceof uglify.JS_Parse_Error &&
+                e.message === "Unexpected token: arrow (=>)";
+        }
+
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error);
+        }
+    });
+
+    it("Should parse a function containing default assignment correctly", function() {
+        var ast = uglify.parse("var a = (a = 123) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // First argument
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_DefaultAssign);
+        assert(ast.body[0].definitions[0].value.argnames[0].left instanceof uglify.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].operator, "=");
+        assert(ast.body[0].definitions[0].value.argnames[0].right instanceof uglify.AST_Number);
+
+        ast = uglify.parse("var a = (a = a) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // First argument
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_DefaultAssign);
+        assert(ast.body[0].definitions[0].value.argnames[0].left instanceof uglify.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].operator, "=");
+        assert(ast.body[0].definitions[0].value.argnames[0].right instanceof uglify.AST_SymbolRef);
+    });
+
+    it("Should parse a function containing default assignments in destructuring correctly", function() {
+        var ast = uglify.parse("var a = ([a = 123]) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // First argument
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].is_array, true);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names.length, 1);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0] instanceof uglify.AST_DefaultAssign);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].left instanceof uglify.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[0].operator, "=");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].right instanceof uglify.AST_Number);
+
+
+        ast = uglify.parse("var a = ({a = 123}) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // First argument
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].is_array, false);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names.length, 1);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0] instanceof uglify.AST_ObjectKeyVal);
+
+        // First object element in first argument
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[0].key, "a");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value instanceof uglify.AST_DefaultAssign);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value.left instanceof uglify.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[0].value.operator, "=");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value.right instanceof uglify.AST_Number);
+
+
+        ast = uglify.parse("var a = ({a: a = 123}) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // First argument
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].is_array, false);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names.length, 1);
+
+        // Content destructuring of first argument
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0] instanceof uglify.AST_ObjectProperty);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[0].key, "a");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value instanceof uglify.AST_DefaultAssign);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value.left instanceof uglify.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[0].value.operator, "=");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value.right instanceof uglify.AST_Number);
+    });
+
+    it("Should parse a function containing default assignments in complex destructuring correctly", function() {
+        var ast = uglify.parse("var a = ([a, [b = 123]]) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // Check first argument
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].is_array, true);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names.length, 2);
+
+        // Check whole destructuring structure of first argument
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0] instanceof uglify.AST_SymbolFunarg);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[1].is_array, true);
+
+        // Check content of second destructuring element (which is the nested destructuring pattern)
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1].names[0] instanceof uglify.AST_DefaultAssign);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1].names[0].left instanceof uglify.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[1].names[0].operator, "=");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1].names[0].right instanceof uglify.AST_Number);
+
+
+        ast = uglify.parse("var a = ([a, {b: c = 123}]) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // Check first argument
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].is_array, true);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names.length, 2);
+
+        // Check whole destructuring structure of first argument
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0] instanceof uglify.AST_SymbolFunarg);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[1].is_array, false);
+
+        // Check content of second destructuring element (which is the nested destructuring pattern)
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1].names[0] instanceof uglify.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[1].names[0].key, "b");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1].names[0].value instanceof uglify.AST_DefaultAssign);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1].names[0].value.left instanceof uglify.AST_SymbolFunarg);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[1].names[0].value.operator, "=");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1].names[0].value.right instanceof uglify.AST_Number);
+
+
+        ast = uglify.parse("var a = ({a, b: {b = 123}}) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // Check first argument
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].is_array, false);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names.length, 2);
+
+        // First argument, property 1
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0] instanceof uglify.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[0].key, "a");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value instanceof uglify.AST_SymbolFunarg);
+
+        // First argument, property 2
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1] instanceof uglify.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[1].key, "b");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1].value instanceof uglify.AST_Destructuring);
+
+        // Check content of nested destructuring
+        var content = ast.body[0].definitions[0].value.argnames[0].names[1].value
+        assert.strictEqual(content.is_array, false);
+        assert.strictEqual(content.names.length, 1);
+        assert(content.names[0] instanceof uglify.AST_ObjectKeyVal);
+
+        // Content of first property in nested destructuring
+        assert.strictEqual(content.names[0].key, "b");
+        assert(content.names[0].value instanceof uglify.AST_DefaultAssign);
+        assert(content.names[0].value.left instanceof uglify.AST_SymbolFunarg);
+        assert.strictEqual(content.names[0].value.operator, "=");
+        assert(content.names[0].value.right instanceof uglify.AST_Number);
+
+
+        ast = uglify.parse("var a = ({a: {b = 123}}) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // Check first argument
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].is_array, false);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names.length, 1);
+
+        // Check whole destructuring structure of first argument
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0] instanceof uglify.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[0].key, "a");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value instanceof uglify.AST_Destructuring);
+
+        // Check content of nested destructuring
+        content = ast.body[0].definitions[0].value.argnames[0].names[0].value
+        assert.strictEqual(content.is_array, false);
+        assert.strictEqual(content.names.length, 1);
+        assert(content.names[0] instanceof uglify.AST_ObjectKeyVal);
+
+        // Check first property of nested destructuring
+        assert.strictEqual(content.names[0].key, "b");
+        assert(content.names[0].value instanceof uglify.AST_DefaultAssign);
+        assert(content.names[0].value.left instanceof uglify.AST_SymbolFunarg);
+        assert.strictEqual(content.names[0].value.operator, "=");
+        assert(content.names[0].value.right instanceof uglify.AST_Number);
+    });
+
+    it("Should parse spread correctly", function() {
+        var ast = uglify.parse("var a = (a, b, ...c) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 3);
+
+        // Check parameters
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_SymbolFunarg);
+        assert(ast.body[0].definitions[0].value.argnames[1] instanceof uglify.AST_SymbolFunarg);
+        assert(ast.body[0].definitions[0].value.argnames[2] instanceof uglify.AST_Expansion);
+        assert(ast.body[0].definitions[0].value.argnames[2].expression instanceof uglify.AST_SymbolFunarg);
+
+
+        ast = uglify.parse("var a = ([a, b, ...c]) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // Check first parameter
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].is_array, true);
+
+        // Check content first parameter
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0] instanceof uglify.AST_SymbolFunarg);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1] instanceof uglify.AST_SymbolFunarg);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[2] instanceof uglify.AST_Expansion);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[2].expression instanceof uglify.AST_SymbolFunarg);
+
+
+        ast = uglify.parse("var a = ([a, b, [c, ...d]]) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // Check first parameter
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].is_array, true);
+
+        // Check content outer destructuring array
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0] instanceof uglify.AST_SymbolFunarg);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[1] instanceof uglify.AST_SymbolFunarg);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[2] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[2].is_array, true);
+
+        // Check content nested destructuring array
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[2].names.length, 2);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[2].names[0] instanceof uglify.AST_SymbolFunarg);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[2].names[1] instanceof uglify.AST_Expansion);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[2].names[1].expression instanceof uglify.AST_SymbolFunarg);
+
+
+        ast = uglify.parse("var a = ({a: [b, ...c]}) => {}");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert.strictEqual(ast.body[0].definitions.length, 1);
+        assert(ast.body[0].definitions[0] instanceof uglify.AST_VarDef);
+        assert(ast.body[0].definitions[0].name instanceof uglify.AST_SymbolVar);
+        assert(ast.body[0].definitions[0].value instanceof uglify.AST_Arrow);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames.length, 1);
+
+        // Check first parameter
+        assert(ast.body[0].definitions[0].value.argnames[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].is_array, false);
+
+        // Check outer destructuring object
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names.length, 1);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0] instanceof uglify.AST_ObjectKeyVal);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[0].key, "a");
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[0].value.is_array, true);
+
+        // Check content nested destructuring array
+        assert.strictEqual(ast.body[0].definitions[0].value.argnames[0].names[0].value.names.length, 2);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value.names[0] instanceof uglify.AST_SymbolFunarg);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value.names[1] instanceof uglify.AST_Expansion);
+        assert(ast.body[0].definitions[0].value.argnames[0].names[0].value.names[1].expression instanceof uglify.AST_SymbolFunarg);
+    });
+
+    it("Should handle arrow function with bind", function() {
+        function minify(code) {
+            return uglify.minify(code, {
+                mangle: false
+            }).code;
+        }
+
+        assert.strictEqual(
+            minify(minify("test(((index) => { console.log(this, index); }).bind(this, 1));")),
+            "test((index=>{console.log(this,index)}).bind(this,1));"
+        );
+        assert.strictEqual(
+            minify(minify('test(((index) => { console.log(this, index); })["bind"](this, 1));')),
+            "test((index=>{console.log(this,index)}).bind(this,1));"
+        );
+    });
+
+});

test/mocha/builtins.js

@@ -0,0 +1,34 @@
+var UglifyJS = require("../../");
+var assert = require("assert");
+
+describe("builtins", function() {
+    it ("Should not mangle builtins", function() {
+        var test = "function foo(something){\n" +
+            "    return [Object,Array,Function,Number,String,Boolean,Error,Math,Date,RegExp,Symbol,Map,Promise,Proxy,Reflect,Set,WeakMap,WeakSet,Float32Array,something];\n" +
+            "};";
+
+        var result = UglifyJS.minify(test, {parse: {bare_returns: true}}).code;
+
+        assert.strictEqual(result.indexOf("something"), -1);
+
+        assert.notEqual(result.indexOf("Object"), -1);
+        assert.notEqual(result.indexOf("Array"), -1);
+        assert.notEqual(result.indexOf("Function"), -1);
+        assert.notEqual(result.indexOf("Number"), -1);
+        assert.notEqual(result.indexOf("String"), -1);
+        assert.notEqual(result.indexOf("Boolean"), -1);
+        assert.notEqual(result.indexOf("Error"), -1);
+        assert.notEqual(result.indexOf("Math"), -1);
+        assert.notEqual(result.indexOf("Date"), -1);
+        assert.notEqual(result.indexOf("RegExp"), -1);
+        assert.notEqual(result.indexOf("Symbol"), -1);
+        assert.notEqual(result.indexOf("Promise"), -1);
+        assert.notEqual(result.indexOf("Proxy"), -1);
+        assert.notEqual(result.indexOf("Reflect"), -1);
+        assert.notEqual(result.indexOf("Set"), -1);
+        assert.notEqual(result.indexOf("WeakMap"), -1);
+        assert.notEqual(result.indexOf("WeakSet"), -1);
+        assert.notEqual(result.indexOf("Map"), -1);
+        assert.notEqual(result.indexOf("Float32Array"), -1);
+    });
+});

test/mocha/class.js

@@ -0,0 +1,57 @@
+var assert = require("assert");
+var uglify = require("../node");
+
+describe("Class", function() {
+    it("Should not accept spread on non-last parameters in methods", function() {
+        var tests = [
+            "class foo { bar(...a, b) { return a.join(b) } }",
+            "class foo { bar(a, b, ...c, d) { return c.join(a + b) + d } }",
+            "class foo { *bar(...a, b) { return a.join(b) } }",
+            "class foo { *bar(a, b, ...c, d) { return c.join(a + b) + d } }"
+        ];
+        var test = function(code) {
+            return function() {
+                uglify.parse(code);
+            }
+        }
+        var error = function(e) {
+            return e instanceof uglify.JS_Parse_Error &&
+                /^Unexpected token: /.test(e.message);
+        }
+
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error);
+        }
+    });
+
+    it("Should return the correct token for class methods", function() {
+        var tests = [
+            {
+                code: "class foo{static test(){}}",
+                token_value_start: "static",
+                token_value_end: "}"
+            },
+            {
+                code: "class bar{*procedural(){}}",
+                token_value_start: "*",
+                token_value_end: "}"
+            },
+            {
+                code: "class foobar{aMethod(){}}",
+                token_value_start: "aMethod",
+                token_value_end: "}"
+            },
+            {
+                code: "class foobaz{get something(){}}",
+                token_value_start: "get",
+                token_value_end: "}"
+            }
+        ];
+
+        for (var i = 0; i < tests.length; i++) {
+            var ast = uglify.parse(tests[i].code);
+            assert.strictEqual(ast.body[0].properties[0].start.value, tests[i].token_value_start);
+            assert.strictEqual(ast.body[0].properties[0].end.value, tests[i].token_value_end);
+        }
+    });
+});

test/mocha/cli.js

@@ -9,7 +9,7 @@ function read(path) {
 describe("bin/uglifyjs", function () {
     var uglifyjscmd = '"' + process.argv[0] + '" bin/uglifyjs';
     it("should produce a functional build when using --self", function (done) {
-        this.timeout(30000);
+        this.timeout(15000);
 
         var command = uglifyjscmd + ' --self -cm --wrap WrappedUglifyJS';
 
@@ -19,9 +19,7 @@ describe("bin/uglifyjs", function () {
             eval(stdout);
 
             assert.strictEqual(typeof WrappedUglifyJS, 'object');
-            var result = WrappedUglifyJS.minify("foo([true,,2+3]);");
-            assert.strictEqual(result.error, undefined);
-            assert.strictEqual(result.code, "foo([!0,,5]);");
+            assert.strictEqual(WrappedUglifyJS.minify("foo([true,,2+3]);").code, "foo([!0,,5]);");
 
             done();
         });
@@ -57,15 +55,15 @@ describe("bin/uglifyjs", function () {
         });
     });
     it("Should append source map to output when using --source-map url=inline", function (done) {
-        var command = uglifyjscmd + " test/input/issue-1323/sample.js --source-map url=inline";
+       var command = uglifyjscmd + " test/input/issue-1323/sample.js --source-map url=inline";
 
-        exec(command, function (err, stdout) {
-            if (err) throw err;
+       exec(command, function (err, stdout) {
+           if (err) throw err;
 
-            assert.strictEqual(stdout, "var bar=function(){function foo(bar){return bar}return foo}();\n" +
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFJQSxJQUFNLFdBQ04sU0FBU0MsSUFBS0QsS0FDVixPQUFPQSxJQUdYLE9BQU9DIn0=\n");
-            done();
-        });
+           assert.strictEqual(stdout, "var bar=function(){function foo(bar){return bar}return foo}();\n" +
+               "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxHQUFJQSxLQUFNLFdBQ04sUUFBU0MsS0FBS0QsS0FDVixNQUFPQSxLQUdYLE1BQU9DIn0=\n");
+           done();
+       });
     });
     it("should not append source map to output when not using --source-map url=inline", function (done) {
         var command = uglifyjscmd + ' test/input/issue-1323/sample.js';
@@ -77,102 +75,85 @@ describe("bin/uglifyjs", function () {
             done();
         });
     });
-    it("should not consider source map file content as source map file name (issue #2082)", function (done) {
-        var command = [
-            uglifyjscmd,
-            "test/input/issue-2082/sample.js",
-            "--source-map", "content=test/input/issue-2082/sample.js.map",
-            "--source-map", "url=inline",
-        ].join(" ");
-
-        exec(command, function (err, stdout, stderr) {
-            if (err) throw err;
-
-            var stderrLines = stderr.split('\n');
-            assert.strictEqual(stderrLines[0], 'INFO: Using input source map: test/input/issue-2082/sample.js.map');
-            assert.notStrictEqual(stderrLines[1], 'INFO: Using input source map: {"version": 3,"sources": ["index.js"],"mappings": ";"}');
-            done();
-        });
-    });
     it("Should work with --keep-fnames (mangle only)", function (done) {
-        var command = uglifyjscmd + ' test/input/issue-1431/sample.js --keep-fnames -m';
+       var command = uglifyjscmd + ' test/input/issue-1431/sample.js --keep-fnames -m';
 
-        exec(command, function (err, stdout) {
-            if (err) throw err;
+       exec(command, function (err, stdout) {
+           if (err) throw err;
 
-            assert.strictEqual(stdout, "function f(r){return function(){function n(n){return n*n}return r(n)}}function g(n){return n(1)+n(2)}console.log(f(g)()==5);\n");
-            done();
-        });
+           assert.strictEqual(stdout, "function f(r){return function(){function n(n){return n*n}return r(n)}}function g(n){return n(1)+n(2)}console.log(f(g)()==5);\n");
+           done();
+       });
     });
     it("Should work with --keep-fnames (mangle & compress)", function (done) {
-        var command = uglifyjscmd + ' test/input/issue-1431/sample.js --keep-fnames -m -c unused=false';
+       var command = uglifyjscmd + ' test/input/issue-1431/sample.js --keep-fnames -m -c unused=false';
 
-        exec(command, function (err, stdout) {
-            if (err) throw err;
+       exec(command, function (err, stdout) {
+           if (err) throw err;
 
-            assert.strictEqual(stdout, "function f(r){return function(){function n(n){return n*n}return r(n)}}function g(n){return n(1)+n(2)}console.log(5==f(g)());\n");
-            done();
-        });
+           assert.strictEqual(stdout, "function f(r){return function(){function n(n){return n*n}return r(n)}}function g(n){return n(1)+n(2)}console.log(5==f(g)());\n");
+           done();
+       });
     });
     it("Should work with keep_fnames under mangler options", function (done) {
-        var command = uglifyjscmd + ' test/input/issue-1431/sample.js -m keep_fnames=true';
+       var command = uglifyjscmd + ' test/input/issue-1431/sample.js -m keep_fnames=true';
 
-        exec(command, function (err, stdout) {
-            if (err) throw err;
+       exec(command, function (err, stdout) {
+           if (err) throw err;
 
-            assert.strictEqual(stdout, "function f(r){return function(){function n(n){return n*n}return r(n)}}function g(n){return n(1)+n(2)}console.log(f(g)()==5);\n");
-            done();
-        });
+           assert.strictEqual(stdout, "function f(r){return function(){function n(n){return n*n}return r(n)}}function g(n){return n(1)+n(2)}console.log(f(g)()==5);\n");
+           done();
+       });
     });
     it("Should work with --define (simple)", function (done) {
-        var command = uglifyjscmd + ' test/input/global_defs/simple.js --define D=5 -c';
+       var command = uglifyjscmd + ' test/input/global_defs/simple.js --define D=5 -c';
 
-        exec(command, function (err, stdout) {
-            if (err) throw err;
+       exec(command, function (err, stdout) {
+           if (err) throw err;
 
-            assert.strictEqual(stdout, "console.log(5);\n");
-            done();
-        });
+           assert.strictEqual(stdout, "console.log(5);\n");
+           done();
+       });
     });
     it("Should work with --define (nested)", function (done) {
-        var command = uglifyjscmd + ' test/input/global_defs/nested.js --define C.D=5,C.V=3 -c';
+       var command = uglifyjscmd + ' test/input/global_defs/nested.js --define C.D=5,C.V=3 -c';
 
-        exec(command, function (err, stdout) {
-            if (err) throw err;
+       exec(command, function (err, stdout) {
+           if (err) throw err;
 
-            assert.strictEqual(stdout, "console.log(3,5);\n");
-            done();
-        });
+           assert.strictEqual(stdout, "console.log(3,5);\n");
+           done();
+       });
     });
     it("Should work with --define (AST_Node)", function (done) {
-        var command = uglifyjscmd + ' test/input/global_defs/simple.js --define console.log=stdout.println -c';
+       var command = uglifyjscmd + ' test/input/global_defs/simple.js --define console.log=stdout.println -c';
 
-        exec(command, function (err, stdout) {
-            if (err) throw err;
+       exec(command, function (err, stdout) {
+           if (err) throw err;
 
-            assert.strictEqual(stdout, "stdout.println(D);\n");
-            done();
-        });
+           assert.strictEqual(stdout, "stdout.println(D);\n");
+           done();
+       });
     });
     it("Should work with `--beautify`", function (done) {
-        var command = uglifyjscmd + ' test/input/issue-1482/input.js -b';
+       var command = uglifyjscmd + ' test/input/issue-1482/input.js -b';
 
-        exec(command, function (err, stdout) {
-            if (err) throw err;
+       exec(command, function (err, stdout) {
+           if (err) throw err;
 
-            assert.strictEqual(stdout, read("test/input/issue-1482/default.js"));
-            done();
-        });
+           assert.strictEqual(stdout, read("test/input/issue-1482/default.js"));
+           done();
+       });
     });
     it("Should work with `--beautify bracketize`", function (done) {
-        var command = uglifyjscmd + ' test/input/issue-1482/input.js -b bracketize';
+       var command = uglifyjscmd + ' test/input/issue-1482/input.js -b bracketize';
 
-        exec(command, function (err, stdout) {
-            if (err) throw err;
+       exec(command, function (err, stdout) {
+           if (err) throw err;
 
-            assert.strictEqual(stdout, read("test/input/issue-1482/bracketize.js"));
-            done();
-        });
+           assert.strictEqual(stdout, read("test/input/issue-1482/bracketize.js"));
+           done();
+       });
     });
     it("Should process inline source map", function(done) {
         var command = uglifyjscmd + " test/input/issue-520/input.js -mc toplevel --source-map content=inline,url=inline";
@@ -192,7 +173,7 @@ describe("bin/uglifyjs", function () {
 
             assert.strictEqual(stdout, [
                 "var bar=function(){function foo(bar){return bar}return foo}();",
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFJQSxJQUFNLFdBQ04sU0FBU0MsSUFBS0QsS0FDVixPQUFPQSxJQUdYLE9BQU9DIn0=",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxHQUFJQSxLQUFNLFdBQ04sUUFBU0MsS0FBS0QsS0FDVixNQUFPQSxLQUdYLE1BQU9DIn0=",
                 "",
             ].join("\n"));
             assert.strictEqual(stderr, "WARN: inline source map not found\n");
@@ -279,244 +260,229 @@ describe("bin/uglifyjs", function () {
         });
     });
     it("Should throw syntax error (5--)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/assign_1.js';
+       var command = uglifyjscmd + ' test/input/invalid/assign_1.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/assign_1.js:1,18",
-                "console.log(1 || 5--);",
-                "                  ^",
-                "ERROR: Invalid use of -- operator"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/assign_1.js:1,18",
+               "console.log(1 || 5--);",
+               "                  ^",
+               "ERROR: Invalid use of -- operator"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (Math.random() /= 2)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/assign_2.js';
+       var command = uglifyjscmd + ' test/input/invalid/assign_2.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/assign_2.js:1,32",
-                "console.log(2 || (Math.random() /= 2));",
-                "                                ^",
-                "ERROR: Invalid assignment"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/assign_2.js:1,32",
+               "console.log(2 || (Math.random() /= 2));",
+               "                                ^",
+               "ERROR: Invalid assignment"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (++this)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/assign_3.js';
+       var command = uglifyjscmd + ' test/input/invalid/assign_3.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/assign_3.js:1,17",
-                "console.log(3 || ++this);",
-                "                 ^",
-                "ERROR: Invalid use of ++ operator"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/assign_3.js:1,17",
+               "console.log(3 || ++this);",
+               "                 ^",
+               "ERROR: Invalid use of ++ operator"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (++null)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/assign_4.js';
+       var command = uglifyjscmd + ' test/input/invalid/assign_4.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/assign_4.js:1,0",
-                "++null",
-                "^",
-                "ERROR: Invalid use of ++ operator"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/assign_4.js:1,0",
+               "++null",
+               "^",
+               "ERROR: Invalid use of ++ operator"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (a.=)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/dot_1.js';
+       var command = uglifyjscmd + ' test/input/invalid/dot_1.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/dot_1.js:1,2",
-                "a.=",
-                "  ^",
-                "ERROR: Unexpected token: operator (=)"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/dot_1.js:1,2",
+               "a.=",
+               "  ^",
+               "ERROR: Unexpected token: operator (=)"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (%.a)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/dot_2.js';
+       var command = uglifyjscmd + ' test/input/invalid/dot_2.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/dot_2.js:1,0",
-                "%.a;",
-                "^",
-                "ERROR: Unexpected token: operator (%)"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/dot_2.js:1,0",
+               "%.a;",
+               "^",
+               "ERROR: Unexpected token: operator (%)"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (a./();)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/dot_3.js';
+       var command = uglifyjscmd + ' test/input/invalid/dot_3.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/dot_3.js:1,2",
-                "a./();",
-                "  ^",
-                "ERROR: Unexpected token: operator (/)"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/dot_3.js:1,2",
+               "a./();",
+               "  ^",
+               "ERROR: Unexpected token: operator (/)"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error ({%: 1})", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/object.js';
+       var command = uglifyjscmd + ' test/input/invalid/object.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/object.js:1,13",
-                "console.log({%: 1});",
-                "             ^",
-                "ERROR: Unexpected token: operator (%)"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/object.js:1,13",
+               "console.log({%: 1});",
+               "             ^",
+               "ERROR: Unexpected token: operator (%)"
+           ].join("\n"));
+           done();
+       });
+    });
+    it("Should throw syntax error (const a)", function(done) {
+       var command = uglifyjscmd + ' test/input/invalid/const.js';
+
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/const.js:7,11",
+               "    const a;",
+               "           ^",
+               "ERROR: Missing initializer in const declaration"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (delete x)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/delete.js';
+       var command = uglifyjscmd + ' test/input/invalid/delete.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/delete.js:13,11",
-                "    delete x;",
-                "           ^",
-                "ERROR: Calling delete on expression not allowed in strict mode"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/delete.js:13,11",
+               "    delete x;",
+               "           ^",
+               "ERROR: Calling delete on expression not allowed in strict mode"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (function g(arguments))", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/function_1.js';
+       var command = uglifyjscmd + ' test/input/invalid/function_1.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/function_1.js:4,11",
-                "function g(arguments) {",
-                "           ^",
-                "ERROR: Unexpected arguments in strict mode"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/function_1.js:4,11",
+               "function g(arguments) {",
+               "           ^",
+               "ERROR: Unexpected arguments in strict mode"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (function eval())", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/function_2.js';
+       var command = uglifyjscmd + ' test/input/invalid/function_2.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/function_2.js:4,9",
-                "function eval() {",
-                "         ^",
-                "ERROR: Unexpected eval in strict mode"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/function_2.js:4,9",
+               "function eval() {",
+               "         ^",
+               "ERROR: Unexpected eval in strict mode"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (iife arguments())", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/function_3.js';
+       var command = uglifyjscmd + ' test/input/invalid/function_3.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/function_3.js:4,10",
-                "!function arguments() {",
-                "          ^",
-                "ERROR: Unexpected arguments in strict mode"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/function_3.js:4,10",
+               "!function arguments() {",
+               "          ^",
+               "ERROR: Unexpected arguments in strict mode"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (catch(eval))", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/try.js';
+       var command = uglifyjscmd + ' test/input/invalid/try.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/try.js:7,18",
-                "    try {} catch (eval) {}",
-                "                  ^",
-                "ERROR: Unexpected eval in strict mode"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/try.js:7,18",
+               "    try {} catch (eval) {}",
+               "                  ^",
+               "ERROR: Unexpected eval identifier as parameter inside strict mode"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should throw syntax error (var eval)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/var.js';
+       var command = uglifyjscmd + ' test/input/invalid/var.js';
 
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/var.js:7,8",
-                "    var eval;",
-                "        ^",
-                "ERROR: Unexpected eval in strict mode"
-            ].join("\n"));
-            done();
-        });
-    });
-    it("Should throw syntax error (else)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/else.js';
-
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/else.js:1,7",
-                "if (0) else 1;",
-                "       ^",
-                "ERROR: Unexpected token: keyword (else)"
-            ].join("\n"));
-            done();
-        });
-    });
-    it("Should throw syntax error (return)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/return.js';
-
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-                "Parse error at test/input/invalid/return.js:1,0",
-                "return 42;",
-                "^",
-                "ERROR: 'return' outside of function"
-            ].join("\n"));
-            done();
-        });
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/var.js:7,8",
+               "    var eval;",
+               "        ^",
+               "ERROR: Unexpected eval in strict mode"
+           ].join("\n"));
+           done();
+       });
     });
     it("Should handle literal string as source map input", function(done) {
         var command = [
@@ -531,7 +497,7 @@ describe("bin/uglifyjs", function () {
 
             assert.strictEqual(stdout, [
                 '"use strict";var foo=function foo(x){return"foo "+x};console.log(foo("bar"));',
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbImluZGV4LmpzIl0sIm5hbWVzIjpbImZvbyIsIngiLCJjb25zb2xlIiwibG9nIl0sIm1hcHBpbmdzIjoiYUFBQSxJQUFJQSxJQUFNLFNBQU5BLElBQU1DLEdBQUEsTUFBSyxPQUFTQSxHQUN4QkMsUUFBUUMsSUFBSUgsSUFBSSJ9",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbImluZGV4LmpzIl0sIm5hbWVzIjpbImZvbyIsIngiLCJjb25zb2xlIiwibG9nIl0sIm1hcHBpbmdzIjoiWUFBQSxJQUFJQSxLQUFNLFFBQU5BLEtBQU1DLEdBQUEsTUFBSyxPQUFTQSxFQUN4QkMsU0FBUUMsSUFBSUgsSUFBSSJ9",
                 ""
             ].join("\n"));
             done();
@@ -554,33 +520,4 @@ describe("bin/uglifyjs", function () {
             done();
         });
     });
-    it("Should print supported options on invalid option syntax", function(done) {
-        var command = uglifyjscmd + " test/input/comments/filter.js -b ascii-only";
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.ok(/^Supported options:\n[\s\S]*?\nERROR: `ascii-only` is not a supported option/.test(stderr), stderr);
-            done();
-        });
-    });
-    it("Should work with --mangle reserved=[]", function (done) {
-        var command = uglifyjscmd + ' test/input/issue-505/input.js -m reserved=[callback]';
-
-        exec(command, function (err, stdout) {
-            if (err) throw err;
-
-            assert.strictEqual(stdout, 'function test(callback){"aaaaaaaaaaaaaaaa";callback(err,data);callback(err,data)}\n');
-            done();
-        });
-    });
-    it("Should work with --mangle reserved=false", function (done) {
-        var command = uglifyjscmd + ' test/input/issue-505/input.js -m reserved=false';
-
-        exec(command, function (err, stdout) {
-            if (err) throw err;
-
-            assert.strictEqual(stdout, 'function test(a){"aaaaaaaaaaaaaaaa";a(err,data);a(err,data)}\n');
-            done();
-        });
-    });
 });

test/mocha/comment.js

@@ -31,7 +31,8 @@ describe("Comment", function() {
             "/*Some comment 2\r\n\r\n\r\n*/\r\n>\n\n\n\n\n\n",
             "/*Some comment 3\r\r\r*/\r>\n\n\n\n\n\n",
             "/*Some comment 4\u2028\u2028\u2028*/\u2028>\n\n\n\n\n\n",
-            "/*Some comment 5\u2029\u2029\u2029*/\u2029>\n\n\n\n\n\n"
+            "/*Some comment 5\u2029\u2029\u2029*/\u2029>\n\n\n\n\n\n",
+            "/*Some comment 6\udbff\udfff\udbff\udfff\n\n\n*/\n>\n\n\n\n\n"
         ];
 
         var fail = function(e) {

test/mocha/destructuring.js

@@ -0,0 +1,138 @@
+var assert = require("assert");
+var uglify = require("../node");
+
+describe("Destructuring", function() {
+    it("Should generate similar trees for destructuring in left hand side expressions, definitions, functions and arrow functions", function() {
+        var patterns = [
+            "[]",
+            "{}",
+
+            "[a, b, c]",
+            "{a: b, c: d}",
+            "{a}",
+            "{a, b}",
+
+            "{a: {}}",
+            "{a: []}",
+            "[{}]",
+            "[[]]",
+            "{a: {b}}",
+
+            // Can't do `a = 123` with lhs expression, so only test in destructuring
+            "[foo = bar]",
+            "{a = 123}",
+            "[{foo: abc = 123}]",
+            "{foo: [abc = 123]}",
+
+            "[...foo]",
+            "[...{}]",
+            "[...[]]"
+
+            // Can't do `...` because that is an invalid lhs expression, spread in array destructuring should be fine though
+        ];
+
+        var types = [
+            {
+                name: "lhs",
+                symbolType: uglify.AST_SymbolRef,
+                tree: function (ast) {
+                    return ast.body[0].body.left;
+                },
+                generate: function (code) {
+                    return "(" + code + " = a)";
+                }
+            },
+            {
+                name: "var",
+                symbolType: uglify.AST_SymbolVar,
+                tree: function (ast) {
+                    return ast.body[0].definitions[0].name;
+                },
+                generate: function (code) {
+                    return "var " + code + " = a";
+                }
+            },
+            {
+                name: "function",
+                symbolType: uglify.AST_SymbolFunarg,
+                tree: function (ast) {
+                    return ast.body[0].argnames[0];
+                },
+                generate: function (code) {
+                    return "function a(" + code + ") {}";
+                }
+            },
+            {
+                name: "arrow",
+                symbolType: uglify.AST_SymbolFunarg,
+                tree: function (ast) {
+                    return ast.body[0].definitions[0].value.argnames[0];
+                },
+                generate: function (code) {
+                    return "var a = (" + code + ") => {}";
+                }
+            }
+        ];
+
+        var walker = function(type, ref, code, result) {
+            var w = new uglify.TreeWalker(function(node) {
+                if (w.parent() instanceof uglify.AST_DefaultAssign &&
+                    w.parent().right === node
+                ) {
+                    return true; // Don't check the content of the default assignment
+
+                } else if (node instanceof uglify.AST_Symbol) {
+                    assert(node instanceof type.symbolType,
+                        node.TYPE + " while " + type.symbolType.TYPE + " expected at pos " +
+                        node.start.pos + " in `" + code + "`  (" + ref + ")"
+                    );
+
+                    result.push([
+                        new uglify.AST_Symbol({
+                            start: node.start,
+                            name: node.name,
+                            end: node.end
+                        }),
+                        w.parent()
+                    ]);
+
+                    return;
+                }
+
+                result.push([node, w.parent()]);
+            });
+
+            return w;
+        };
+
+        var getNodeType = function(node) {
+            return node[0].TYPE + (node[1] ? " " + node[1].TYPE : "");
+        }
+
+        for (var i = 0; i < patterns.length; i++) {
+            var results = [];
+
+            for (var j = 0; j < types.length; j++) {
+                var code = types[j].generate(patterns[i])
+                var ast = types[j].tree(
+                    uglify.parse(code)
+                );
+                results.push([]);
+                ast.walk(walker(
+                    types[j],
+                    "`" + patterns[i] + "` on " + types[j].name,
+                    code,
+                    results[j]
+                ));
+
+                if (j > 0) {
+                    assert.deepEqual(
+                        results[0].map(getNodeType),
+                        results[j].map(getNodeType),
+                        "AST disagree on " + patterns[i] + " with " + types[j].name
+                    );
+                }
+            }
+        }
+    });
+});

test/mocha/directives.js

@@ -62,10 +62,10 @@ describe("Directives", function() {
     it("Should know which strings are directive and which ones are not", function() {
         var test_directive = function(tokenizer, test) {
             test.directives.map(function(directive) {
-                assert.strictEqual(tokenizer.has_directive(directive), true, directive + " in " + test.input);
+                assert.strictEqual(tokenizer.has_directive(directive), true, "Didn't found directive `" + directive + "` at the end of `" + test.input + '`');
             });
             test.non_directives.map(function(fake_directive) {
-                assert.strictEqual(tokenizer.has_directive(fake_directive), false, fake_directive + " in " + test.input);
+                assert.strictEqual(tokenizer.has_directive(fake_directive), false, "Unexpectedly found directive `" + fake_directive + "` at the end of `" + test.input + '`');
             });
         }
 
@@ -156,6 +156,16 @@ describe("Directives", function() {
                 input: '"use strict";try{"use asm";',
                 directives: ["use strict"],
                 non_directives: ["use\nstrict", "use \nstrict", "use asm"]
+            },
+            {
+                input: 'class foo {',
+                directives: ["use strict"],
+                non_directives: ["use\nstrict", "use asm"]
+            },
+            {
+                input: 'class foo {}',
+                directives: [],
+                non_directives: ["use strict", "use asm", "use\nstrict"]
             }
         ];
 
@@ -351,31 +361,61 @@ describe("Directives", function() {
         var tests = [
             [
                 '"use strict";"use strict";"use strict";"use foo";"use strict";;"use sloppy";doSomething("foo");',
-                '"use strict";"use foo";doSomething("foo");',
-                'function f(){ "use strict" }',
-                'function f(){ "use asm" }',
-                'function f(){ "use nondirective" }',
-                'function f(){ ;"use strict" }',
-                'function f(){ "use \n"; }',
+                '"use strict";"use foo";doSomething("foo");'
             ],
             [
                  // Nothing gets optimised in the compressor because "use asm" is the first statement
                 '"use asm";"use\\x20strict";1+1;',
-                '"use asm";;"use strict";1+1;', // Yet, the parser noticed that "use strict" wasn't a directive
-                'function f(){"use strict"}',
-                'function f(){"use asm"}',
-                'function f(){"use nondirective"}',
-                'function f(){}',
-                'function f(){}',
+                '"use asm";;"use strict";1+1;' // Yet, the parser noticed that "use strict" wasn't a directive
             ]
         ];
 
         for (var i = 0; i < tests.length; i++) {
             assert.strictEqual(
-                uglify.minify(tests[i][0]).code,
+                uglify.minify(tests[i][0], {compress: {collapse_vars: true, side_effects: true}}).code,
                 tests[i][1],
                 tests[i][0]
             );
         }
     });
+    it("Should be detect implicit usages of strict mode from tree walker", function() {
+        var tests = [
+            {
+                input: 'class foo {bar(){_check_}}',
+                directives: ["use strict"],
+                non_directives: ["use bar"]
+            },
+            {
+                input: 'class foo {bar(){}}_check_',
+                directives: [],
+                non_directives: ["use strict", "use bar"]
+            }
+        ];
+
+        var i = 0;
+        var checked;
+        var checkWalker = new uglify.TreeWalker(function(node, descend) {
+            if (node instanceof uglify.AST_Symbol && node.name === "_check_") {
+                checked = true;
+                for (var j = 0; j < tests[i].directives.length; j++) {
+                    assert.ok(checkWalker.has_directive(tests[i].directives[j]),
+                        "Did not found directive '" + tests[i].directives[j] +  "' in test " + tests[i].input)
+                }
+                for (var k = 0; k < tests[i].non_directives.length; k++) {
+                    assert.equal(checkWalker.has_directive(tests[i].non_directives[k]), undefined,
+                        "Found directive '" + tests[i].non_directives[k] +  "' in test " + tests[i].input)
+                }
+            }
+        });
+
+        for (; i < tests.length; i++) {
+            // Do tests - iterate the ast in each test - check only when _check_ occurs - fail when no _check_ has been found
+            checked = false;
+            var ast = uglify.parse(tests[i].input);
+            ast.walk(checkWalker);
+            if (!checked) {
+                throw "No _check_ symbol found in " + tests[i].input;
+            }
+        }
+    });
 });

test/mocha/eof.js

@@ -0,0 +1,35 @@
+var assert = require("assert");
+var uglify = require("../node");
+
+describe("EOF", function() {
+    it("Should test code for at least throwing syntax error when incomplete", function() {
+        var error = function(e) {
+            return e instanceof uglify.JS_Parse_Error;
+        }
+        var parse = function(test) {
+            return function() {
+                uglify.parse(test);
+            }
+        }
+        // Chops off 1 char at a time until limit or start of string is reached
+        // The passed code must still be valid when unchopped
+        var test_eol = function(input, chopLimit) {
+            if (chopLimit === undefined) {
+                chopLimit = input.length - 1;
+            }
+
+            assert.doesNotThrow(parse(input), "Expected valid code for \n" + input);
+
+            for (var i = input.length - 1; chopLimit > 0; chopLimit--, i--) {
+                var code = input.substr(0, i);
+                assert.throws(parse(code), error, code);
+            }
+        }
+
+        test_eol("var \\u1234", 7); // Incomplete identifier
+        test_eol("'Incomplete string'");
+        test_eol("/Unterminated regex/");
+        test_eol("` Unterminated template string`");
+        test_eol("/* Unfinishing multiline comment */");
+    });
+});

test/mocha/export.js

@@ -0,0 +1,40 @@
+var assert = require("assert");
+var uglify = require("../node");
+
+describe("Export", function() {
+    it ("Should parse export directives", function() {
+
+        var inputs = [
+            ['export * from "a.js"', ['*'], "a.js"],
+            ['export {A} from "a.js"', ['A'], "a.js"],
+            ['export {A as X} from "a.js"', ['X'], "a.js"],
+            ['export {A as Foo, B} from "a.js"', ['Foo', 'B'], "a.js"],
+            ['export {A, B} from "a.js"', ['A', 'B'], "a.js"],
+        ];
+
+        var test = function(code) {
+            return uglify.parse(code);
+        };
+
+        var extractNames = function(symbols) {
+            var ret = [];
+            for (var i = 0; i < symbols.length; i++) {
+                ret.push(symbols[i].name.name)
+            }
+            return ret;
+        };
+
+        for (var i = 0; i < inputs.length; i++) {
+            var ast = test(inputs[i][0]);
+            var names = inputs[i][1];
+            var filename = inputs[i][2];
+            assert(ast instanceof uglify.AST_Toplevel);
+            assert.equal(ast.body.length, 1);
+            var st = ast.body[0];
+            assert(st instanceof uglify.AST_Export);
+            var actualNames = extractNames(st.exported_names);
+            assert.deepEqual(actualNames, names);
+            assert.equal(st.module_name.value, filename)
+        }
+    })
+});

test/mocha/expression.js

@@ -0,0 +1,32 @@
+var assert = require("assert");
+var uglify = require("../node");
+
+describe("Expression", function() {
+    it("Should not allow the first exponentiation operator to be prefixed with an unary operator", function() {
+        var tests = [
+            "+5 ** 3",
+            "-5 ** 3",
+            "~5 ** 3",
+            "!5 ** 3",
+            "void 5 ** 3",
+            "typeof 5 ** 3",
+            "delete 5 ** 3",
+            "var a = -(5) ** 3;"
+        ];
+
+        var fail = function(e) {
+            return e instanceof uglify.JS_Parse_Error &&
+                /^Unexpected token: operator \((?:[!+~-]|void|typeof|delete)\)/.test(e.message);
+        }
+
+        var exec = function(test) {
+            return function() {
+                uglify.parse(test);
+            }
+        }
+
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(exec(tests[i]), fail, tests[i]);
+        }
+    });
+});

test/mocha/function.js

@@ -0,0 +1,252 @@
+var assert = require("assert");
+var uglify = require("../node");
+
+describe("Function", function() {
+    it ("Should parse binding patterns correctly", function() {
+        // Function argument nodes are correct
+        function get_args(args) {
+            return args.map(function (arg) {
+                return [arg.TYPE, arg.name];
+            });
+        }
+
+        // Destructurings as arguments
+        var destr_fun1 = uglify.parse('(function ({a, b}) {})').body[0].body;
+        var destr_fun2 = uglify.parse('(function ([a, [b]]) {})').body[0].body;
+        var destr_fun3 = uglify.parse('({a, b}) => null').body[0].body;
+        var destr_fun4 = uglify.parse('([a, [b]]) => null').body[0].body;
+
+        assert.equal(destr_fun1.argnames.length, 1);
+        assert.equal(destr_fun2.argnames.length, 1);
+        assert.equal(destr_fun3.argnames.length, 1);
+        assert.equal(destr_fun4.argnames.length, 1);
+
+        var destruct1 = destr_fun1.argnames[0];
+        var destruct2 = destr_fun2.argnames[0];
+        var destruct3 = destr_fun3.argnames[0];
+        var destruct4 = destr_fun4.argnames[0];
+
+        assert(destruct1 instanceof uglify.AST_Destructuring);
+        assert(destruct2 instanceof uglify.AST_Destructuring);
+        assert(destruct3 instanceof uglify.AST_Destructuring);
+        assert(destruct4 instanceof uglify.AST_Destructuring);
+        assert(destruct2.names[1] instanceof uglify.AST_Destructuring);
+        assert(destruct4.names[1] instanceof uglify.AST_Destructuring);
+
+        assert.equal(destruct1.start.value, '{');
+        assert.equal(destruct1.end.value, '}');
+        assert.equal(destruct2.start.value, '[');
+        assert.equal(destruct2.end.value, ']');
+        assert.equal(destruct3.start.value, '{');
+        assert.equal(destruct3.end.value, '}');
+        assert.equal(destruct4.start.value, '[');
+        assert.equal(destruct4.end.value, ']');
+
+        assert.equal(destruct1.is_array, false);
+        assert.equal(destruct2.is_array, true);
+        assert.equal(destruct3.is_array, false);
+        assert.equal(destruct4.is_array, true);
+
+        // destruct 1
+        assert.deepEqual(
+            [
+                destruct1.names[0].TYPE,
+                destruct1.names[0].key,
+                destruct1.names[0].value.name
+            ],
+            ['ObjectKeyVal', 'a', 'a']
+        );
+        assert.deepEqual(
+            [
+                destruct1.names[1].TYPE,
+                destruct1.names[1].key,
+                destruct1.names[1].value.name
+            ],
+            ['ObjectKeyVal', 'b', 'b']
+        );
+
+        // destruct 2
+        assert.deepEqual(
+            [
+                destruct2.names[0].TYPE,
+                destruct2.names[0].name
+            ],
+            ['SymbolFunarg', 'a']
+        );
+        assert.deepEqual(
+            [
+                destruct2.names[1].names[0].TYPE,
+                destruct2.names[1].names[0].name
+            ],
+            ['SymbolFunarg', 'b']
+        );
+
+        // destruct 3
+        assert.strictEqual(typeof destruct3.names[0].key, "string");
+        assert.strictEqual(destruct3.names[0].key, "a");
+        assert.strictEqual(destruct3.names[0].value.TYPE, "SymbolFunarg");
+        assert.strictEqual(destruct3.names[0].value.name, "a");
+        assert.strictEqual(typeof destruct3.names[1].key, "string");
+        assert.strictEqual(destruct3.names[1].key, "b");
+        assert.strictEqual(destruct3.names[1].value.TYPE, "SymbolFunarg");
+        assert.strictEqual(destruct3.names[1].value.name, "b");
+
+        // destruct 4
+        assert.deepEqual(
+            [
+                destruct4.names[0].TYPE,
+                destruct4.names[0].name
+            ],
+            ['SymbolFunarg', 'a']
+        );
+        assert.strictEqual(destruct4.names[1].TYPE, "Destructuring");
+        assert.deepEqual(
+            [
+                destruct4.names[1].names[0].TYPE,
+                destruct4.names[1].names[0].name
+            ],
+            ['SymbolFunarg', 'b']
+        );
+
+        assert.deepEqual(
+            get_args(destr_fun1.args_as_names()),
+            [['SymbolFunarg', 'a'], ['SymbolFunarg', 'b']]
+        );
+        assert.deepEqual(
+            get_args(destr_fun2.args_as_names()),
+            [['SymbolFunarg', 'a'], ['SymbolFunarg', 'b']]
+        );
+        assert.deepEqual(
+            get_args(destr_fun3.args_as_names()),
+            [['SymbolFunarg', 'a'], ['SymbolFunarg', 'b']]
+        );
+        assert.deepEqual(
+            get_args(destr_fun4.args_as_names()),
+            [['SymbolFunarg', 'a'], ['SymbolFunarg', 'b']]
+        );
+
+        // Making sure we don't accidentally accept things which
+        // Aren't argument destructurings
+
+        assert.throws(function () {
+            uglify.parse('(function ( { a, [ b ] } ) { })')
+        });
+
+        assert.throws(function () {
+            uglify.parse('(function (1) { })');
+        }, /Invalid function parameter/);
+
+        assert.throws(function () {
+            uglify.parse('(function (this) { })');
+        });
+
+        assert.throws(function () {
+            uglify.parse('(function ([1]) { })');
+        }, /Invalid function parameter/);
+
+        assert.throws(function () {
+            uglify.parse('(function [a] { })');
+        });
+
+        // generators
+        var generators_def = uglify.parse('function* fn() {}').body[0];
+        assert.equal(generators_def.is_generator, true);
+
+        assert.throws(function () {
+            uglify.parse('function* (){ }');
+        });
+
+        var generators_yield_def = uglify.parse('function* fn() {\nyield remote();\}').body[0].body[0];
+        assert.strictEqual(generators_yield_def.body.is_star, false);
+    });
+    it("Should not accept spread on non-last parameters", function() {
+        var tests = [
+            "var a = function(...a, b) { return a.join(b) }",
+            "var b = function(a, b, ...c, d) { return c.join(a + b) + d }",
+            "function foo(...a, b) { return a.join(b) }",
+            "function bar(a, b, ...c, d) { return c.join(a + b) + d }",
+            "var a = function*(...a, b) { return a.join(b) }",
+            "var b = function*(a, b, ...c, d) { return c.join(a + b) + d }",
+            "function* foo(...a, b) { return a.join(b) }",
+            "function* bar(a, b, ...c, d) { return c.join(a + b) + d }"
+        ];
+        var test = function(code) {
+            return function() {
+                uglify.parse(code);
+            }
+        }
+        var error = function(e) {
+            return e instanceof uglify.JS_Parse_Error &&
+                /^Unexpected token: /.test(e.message);
+        }
+
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error);
+        }
+    });
+    it("Should not accept empty parameters after elision", function() {
+        var tests = [
+            "(function(,){})()",
+            "(function(a,){})()",
+        ];
+        var test = function(code) {
+            return function() {
+                uglify.parse(code);
+            }
+        }
+        var error = function(e) {
+            return e instanceof uglify.JS_Parse_Error &&
+                e.message === "Invalid function parameter";
+        }
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error);
+        }
+    });
+    it("Should not accept an initializer when parameter is a rest parameter", function() {
+        var tests = [
+            "(function(...a = b){})()",
+            "(function(a, ...b = [c, d]))"
+        ];
+        var test = function(code) {
+            return function () {
+                uglify.parse(code);
+            }
+        }
+        var error = function (e) {
+            return e instanceof uglify.JS_Parse_Error;
+        }
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error, tests[i]);
+        }
+    });
+    it("Shoult not accept duplicated identifiers inside parameters in strict mode or when using default assigment or spread", function() {
+        // From: ES2016 9.2.12 FunctionDeclarationInstantiation (func, argumentsList)
+        // NOTE Early errors ensure that duplicate parameter names can only occur
+        // in non-strict functions that do not have parameter default values or
+        // rest parameters.
+        var tests = [
+            "(function(a = 1, a){})()",
+            "(function(a, [a = 3]){})()",
+            "(function(a, b, c, d, [{e: [...a]}]){})()",
+            "'use strict'; (function(a, a){})",
+            "(function({a, a = b}))",
+            "(function(a, [...a]){})",
+            "(function(a, ...a){})",
+            "(function(a, [a, ...b]){})",
+            "(function(a, {b: a, c: [...d]}){})",
+            "(function(a, a, {b: [...c]}){})"
+        ];
+        var test = function(code) {
+            return function () {
+                uglify.parse(code);
+            }
+        }
+        var error = function (e) {
+            return e instanceof uglify.JS_Parse_Error &&
+                /^Parameter [a-zA-Z]+ was used already$/.test(e.message);
+        }
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error, tests[i]);
+        }
+    });
+});

test/mocha/getter-setter.js

@@ -71,7 +71,7 @@ describe("Getters and setters", function() {
         var fail = function(data) {
             return function (e) {
                 return e instanceof UglifyJS.JS_Parse_Error &&
-                    e.message === "Unexpected token: operator (" + data.operator + ")";
+                    /^Unexpected token: /.test(e.message);
             };
         };
 

test/mocha/glob.js

@@ -31,7 +31,7 @@ describe("bin/uglifyjs with input file globs", function() {
         exec(command, function(err, stdout) {
             if (err) throw err;
 
-            assert.strictEqual(stdout, 'var print=console.log.bind(console);print("qux",9,6),print("Foo:",2*11);\n');
+            assert.strictEqual(stdout, 'var print=console.log.bind(console),a=function(n){return 3*n}(3),b=function(n){return n/2}(12);print("qux",a,b),function(n){print("Foo:",2*n)}(11);\n');
             done();
         });
     });

test/mocha/lhs-expressions.js

@@ -0,0 +1,265 @@
+var assert = require("assert");
+var uglify = require("../node");
+
+describe("Left-hand side expressions", function () {
+    it("Should parse destructuring with const/let/var correctly", function () {
+        var decls = uglify.parse('var {a,b} = foo, { c, d } = bar');
+
+        assert.equal(decls.body[0].TYPE, 'Var');
+        assert.equal(decls.body[0].definitions.length, 2);
+
+        // Item 1
+        assert.equal(decls.body[0].definitions[0].name.TYPE, 'Destructuring');
+        assert.equal(decls.body[0].definitions[0].value.TYPE, 'SymbolRef');
+
+        // Item 2
+        assert.equal(decls.body[0].definitions[1].name.TYPE, 'Destructuring');
+        assert.equal(decls.body[0].definitions[1].value.TYPE, 'SymbolRef');
+
+        var nested_def = uglify.parse('var [{x}] = foo').body[0].definitions[0];
+
+        assert.equal(nested_def.name.names[0].names[0].TYPE, 'ObjectKeyVal');
+        assert.equal(nested_def.name.names[0].names[0].value.TYPE, 'SymbolVar');
+        assert.equal(nested_def.name.names[0].names[0].key, 'x');
+        assert.equal(nested_def.name.names[0].names[0].value.name, 'x');
+
+        var holey_def = uglify.parse('const [,,third] = [1,2,3]').body[0].definitions[0];
+
+        assert.equal(holey_def.name.names[0].TYPE, 'Hole');
+        assert.equal(holey_def.name.names[1].TYPE, 'Hole');
+        assert.equal(holey_def.name.names[2].TYPE, 'SymbolConst');
+
+        var expanding_def = uglify.parse('var [first, ...rest] = [1,2,3]').body[0].definitions[0];
+
+        assert.equal(expanding_def.name.names[0].TYPE, 'SymbolVar');
+        assert.equal(expanding_def.name.names[1].TYPE, 'Expansion');
+        assert.equal(expanding_def.name.names[1].expression.TYPE, 'SymbolVar');
+    });
+
+    it("Parser should use AST_Array for array literals", function() {
+        var ast = uglify.parse('["foo", "bar"]');
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+        assert(ast.body[0].body instanceof uglify.AST_Array);
+
+        ast = uglify.parse('a = ["foo"]');
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_SymbolRef);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_Array);
+    });
+
+    it("Parser should use AST_Object for object literals", function() {
+        var ast = uglify.parse('({foo: "bar"})');
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+        assert(ast.body[0].body instanceof uglify.AST_Object);
+
+        // This example should be fine though
+        ast = uglify.parse('a = {foo: "bar"}');
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_SymbolRef);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_Object);
+    });
+
+    it("Parser should use AST_Destructuring for array assignment patterns", function() {
+        var ast = uglify.parse('[foo, bar] = [1, 2]');
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.is_array, true);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_Array);
+    });
+
+    it("Parser should use AST_Destructuring for object assignment patterns", function() {
+        var ast = uglify.parse('({a: b, b: c} = {b: "c", c: "d"})');
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.is_array, false);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_Object);
+    });
+
+    it("Parser should be able to handle nested destructuring", function() {
+        var ast = uglify.parse('[{a,b},[d, e, f, {g, h}]] = [{a: 1, b: 2}, [3, 4, 5, {g: 6, h: 7}]]');
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.is_array, true);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_Array);
+
+        assert(ast.body[0].body.left.names[0] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.names[0].is_array, false);
+
+        assert(ast.body[0].body.left.names[1] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.names[1].is_array, true);
+
+        assert(ast.body[0].body.left.names[1].names[3] instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.names[1].names[3].is_array, false);
+    });
+
+    it("Should handle spread operator in destructuring", function() {
+        var ast = uglify.parse("[a, b, ...c] = [1, 2, 3, 4, 5]");
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.is_array, true);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_Array);
+
+        assert(ast.body[0].body.left.names[0] instanceof uglify.AST_SymbolRef);
+        assert(ast.body[0].body.left.names[1] instanceof uglify.AST_SymbolRef);
+
+        assert(ast.body[0].body.left.names[2] instanceof uglify.AST_Expansion);
+    });
+
+    it("Should handle default assignments in destructuring", function() {
+        var ast = uglify.parse("({x: v, z = z + 5} = obj);");
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.is_array, false);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_SymbolRef);
+
+        assert(ast.body[0].body.left.names[0].value instanceof uglify.AST_SymbolRef);
+        assert.strictEqual(ast.body[0].body.left.names[0].start.value, "x");
+
+        assert(ast.body[0].body.left.names[1].value instanceof uglify.AST_DefaultAssign);
+        assert.strictEqual(ast.body[0].body.left.names[1].start.value, "z");
+        assert(ast.body[0].body.left.names[1].value.left instanceof uglify.AST_SymbolRef);
+        assert.strictEqual(ast.body[0].body.left.names[1].value.operator, "=");
+        assert(ast.body[0].body.left.names[1].value.right instanceof uglify.AST_Binary);
+
+
+        ast = uglify.parse("({x = 123} = obj);");
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.is_array, false);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_SymbolRef);
+
+        assert(ast.body[0].body.left.names[0].value instanceof uglify.AST_DefaultAssign);
+        assert.strictEqual(ast.body[0].body.left.names[0].value.operator, "=");
+        assert(ast.body[0].body.left.names[0].value.left instanceof uglify.AST_SymbolRef);
+
+
+        ast = uglify.parse("[x, y = 5] = foo");
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.is_array, true);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_SymbolRef);
+
+        assert(ast.body[0].body.left.names[0] instanceof uglify.AST_SymbolRef);
+        assert.strictEqual(ast.body[0].body.left.names[0].start.value, "x");
+
+        assert(ast.body[0].body.left.names[1] instanceof uglify.AST_DefaultAssign);
+        assert(ast.body[0].body.left.names[1].left instanceof uglify.AST_SymbolRef);
+        assert.strictEqual(ast.body[0].body.left.names[1].start.value, "y");
+    });
+
+    it("Should handle default assignments containing assignments in a destructuring", function() {
+        var ast = uglify.parse("[x, y = z = 2] = a;");
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.is_array, true);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_SymbolRef);
+
+        assert(ast.body[0].body.left.names[0] instanceof uglify.AST_SymbolRef);
+
+        assert(ast.body[0].body.left.names[1] instanceof uglify.AST_DefaultAssign);
+        assert(ast.body[0].body.left.names[1].left instanceof uglify.AST_SymbolRef);
+        assert.equal(ast.body[0].body.left.names[1].operator, "=");
+        assert(ast.body[0].body.left.names[1].right instanceof uglify.AST_Assign);
+
+        assert(ast.body[0].body.left.names[1].right.left instanceof uglify.AST_SymbolRef);
+        assert.equal(ast.body[0].body.left.names[1].right.operator, "=");
+        assert(ast.body[0].body.left.names[1].right.right instanceof uglify.AST_Number);
+
+        ast = uglify.parse("({a: a = 123} = obj)");
+        assert(ast.body[0] instanceof uglify.AST_SimpleStatement);
+
+        assert(ast.body[0].body instanceof uglify.AST_Assign);
+        assert(ast.body[0].body.left instanceof uglify.AST_Destructuring);
+        assert.strictEqual(ast.body[0].body.left.is_array, false);
+        assert.equal(ast.body[0].body.operator, "=");
+        assert(ast.body[0].body.right instanceof uglify.AST_SymbolRef);
+
+        assert(ast.body[0].body.left.names[0] instanceof uglify.AST_ObjectProperty);
+        assert.strictEqual(ast.body[0].body.left.names[0].key, "a");
+        assert(ast.body[0].body.left.names[0].value instanceof uglify.AST_DefaultAssign);
+        assert(ast.body[0].body.left.names[0].value.left instanceof uglify.AST_SymbolRef);
+        assert.strictEqual(ast.body[0].body.left.names[0].value.operator, "=");
+        assert(ast.body[0].body.left.names[0].value.right instanceof uglify.AST_Number);
+    });
+
+    it("Should allow multiple spread in array literals", function() {
+        var ast = uglify.parse("var a = [1, 2, 3], b = [4, 5, 6], joined; joined = [...a, ...b]");
+        assert(ast.body[0] instanceof uglify.AST_Var);
+        assert(ast.body[1] instanceof uglify.AST_SimpleStatement);
+
+        // Check statement containing array with spreads
+        assert(ast.body[1].body instanceof uglify.AST_Assign);
+        assert(ast.body[1].body.left instanceof uglify.AST_SymbolRef);
+        assert.equal(ast.body[1].body.operator, "=");
+        assert(ast.body[1].body.right instanceof uglify.AST_Array);
+
+        // Check array content
+        assert.strictEqual(ast.body[1].body.right.elements.length, 2);
+        assert(ast.body[1].body.right.elements[0] instanceof uglify.AST_Expansion);
+        assert(ast.body[1].body.right.elements[0].expression instanceof uglify.AST_SymbolRef);
+        assert(ast.body[1].body.right.elements[0].expression.name, "a");
+        assert(ast.body[1].body.right.elements[1] instanceof uglify.AST_Expansion);
+        assert(ast.body[1].body.right.elements[1].expression instanceof uglify.AST_SymbolRef);
+        assert(ast.body[1].body.right.elements[1].expression.name, "b");
+    });
+
+    it("Should not allow spread on invalid locations", function() {
+        var expect = function(input, expected) {
+            var execute = function(input) {
+                return function() {
+                    uglify.parse(input);
+                }
+            }
+            var check = function(e) {
+                return e instanceof uglify.JS_Parse_Error &&
+                    e.message === expected;
+            }
+
+            assert.throws(execute(input), check);
+        }
+
+        // Spreads are not allowed in destructuring array if it's not the last element
+        expect("[...a, ...b] = [1, 2, 3, 4]", "Spread must the be last element in destructuring array");
+
+        // Multiple spreads are not allowed in destructuring array
+        expect("[...a, ...b] = [1, 2, 3, 4]", "Spread must the be last element in destructuring array");
+
+        // Spread in obvious object pattern
+        expect("({...a} = foo)", "Unexpected token: expand (...)");
+
+        // Spread in block should not be allowed
+        expect("{...a} = foo", "Unexpected token: expand (...)");
+
+        // Not in standard yet
+        expect("let foo = {bar: 42}, bar; bar = {...foo}", "Unexpected token: expand (...)");
+    });
+});

test/mocha/minify.js

@@ -13,13 +13,6 @@ describe("minify", function() {
         assert.strictEqual(result.code, 'function foo(n){return n?3:7}');
     });
 
-    it("Should skip inherited keys from `files`", function() {
-        var files = Object.create({ skip: this });
-        files[0] = "alert(1 + 1)";
-        var result = Uglify.minify(files);
-        assert.strictEqual(result.code, "alert(2);");
-    });
-
     describe("keep_quoted_props", function() {
         it("Should preserve quotes in object literals", function() {
             var js = 'var foo = {"x": 1, y: 2, \'z\': 3};';
@@ -113,7 +106,7 @@ describe("minify", function() {
                         content: "inline"
                     }
                 });
-                assert.strictEqual(result.code, "var bar=function(){return function(bar){return bar}}();");
+                assert.strictEqual(result.code, "var bar=function(){function foo(bar){return bar}return foo}();");
                 assert.strictEqual(warnings.length, 1);
                 assert.strictEqual(warnings[0], "inline source map not found");
             } finally {
@@ -145,25 +138,13 @@ describe("minify", function() {
             });
             var code = result.code;
             assert.strictEqual(code, "var a=function(n){return n};\n" +
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsiYSIsImZvbyJdLCJtYXBwaW5ncyI6IkFBQUEsSUFBSUEsRUFBSSxTQUFTQyxHQUFPLE9BQU9BIn0=");
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsiYSIsImZvbyJdLCJtYXBwaW5ncyI6IkFBQUEsR0FBSUEsR0FBSSxTQUFTQyxHQUFPLE1BQU9BIn0=");
         });
         it("should not append source map to output js when sourceMapInline is not enabled", function() {
             var result = Uglify.minify('var a = function(foo) { return foo; };');
             var code = result.code;
             assert.strictEqual(code, "var a=function(n){return n};");
         });
-        it("should work with max_line_len", function() {
-            var result = Uglify.minify(read("./test/input/issue-505/input.js"), {
-                output: {
-                    max_line_len: 20
-                },
-                sourceMap: {
-                    url: "inline"
-                }
-            });
-            assert.strictEqual(result.error, undefined);
-            assert.strictEqual(result.code, read("./test/input/issue-505/output.js"));
-        });
     });
 
     describe("#__PURE__", function() {
@@ -200,31 +181,4 @@ describe("minify", function() {
             assert.strictEqual(err.col, 12);
         });
     });
-
-    describe("global_defs", function() {
-        it("should throw for non-trivial expressions", function() {
-            var result = Uglify.minify("alert(42);", {
-                compress: {
-                    global_defs: {
-                        "@alert": "debugger"
-                    }
-                }
-            });
-            var err = result.error;
-            assert.ok(err instanceof Error);
-            assert.strictEqual(err.stack.split(/\n/)[0], "Error: Can't handle expression: debugger");
-        });
-        it("should skip inherited properties", function() {
-            var foo = Object.create({ skip: this });
-            foo.bar = 42;
-            var result = Uglify.minify("alert(FOO);", {
-                compress: {
-                    global_defs: {
-                        FOO: foo
-                    }
-                }
-            });
-            assert.strictEqual(result.code, "alert({bar:42});");
-        });
-    });
 });

test/mocha/new.js

@@ -1,5 +1,5 @@
 var assert = require("assert");
-var uglify = require("../../");
+var uglify = require("../node");
 
 describe("New", function() {
     it("Should add trailing parentheses for new expressions with zero arguments in beautify mode", function() {
@@ -83,4 +83,11 @@ describe("New", function() {
             );
         }
     });
+
+    it("Should check target in new.target", function() {
+        assert.throws(function() {uglify.parse("new.blah")}, function(e) {
+            return e instanceof uglify.JS_Parse_Error
+                && e.message === "Unexpected token name «blah», expected name «target»";
+        });
+    });
 });

test/mocha/object.js

@@ -0,0 +1,131 @@
+var Uglify = require("../node");
+var assert = require("assert");
+
+describe("Object", function() {
+    it("Should allow objects to have a methodDefinition as property", function() {
+        var code = "var a = {test() {return true;}}";
+        assert.equal(Uglify.minify(code).code, "var a={test(){return!0}};");
+    });
+
+    it("Should not allow objects to use static keywords like in classes", function() {
+        var code = "{static test() {}}";
+        var parse = function() {
+            Uglify.parse(code);
+        }
+        var expect = function(e) {
+            return e instanceof Uglify.JS_Parse_Error;
+        }
+        assert.throws(parse, expect);
+    });
+
+    it("Should not allow objects to have static computed properties like in classes", function() {
+        var code = "var foo = {static [123](){}}";
+        var parse = function() {
+            console.log(Uglify.parse(code).body[0].body[0]);
+        }
+        var expect = function(e) {
+            return e instanceof Uglify.JS_Parse_Error;
+        }
+        assert.throws(parse, expect);
+    });
+    it("Should not accept operator tokens as property/getter/setter name", function() {
+        var illegalOperators = [
+            "++",
+            "--",
+            "+",
+            "-",
+            "!",
+            "~",
+            "&",
+            "|",
+            "^",
+            "*",
+            "/",
+            "%",
+            ">>",
+            "<<",
+            ">>>",
+            "<",
+            ">",
+            "<=",
+            ">=",
+            "==",
+            "===",
+            "!=",
+            "!==",
+            "?",
+            "=",
+            "+=",
+            "-=",
+            "/=",
+            "*=",
+            "%=",
+            ">>=",
+            "<<=",
+            ">>>=",
+            "|=",
+            "^=",
+            "&=",
+            "&&",
+            "||"
+        ];
+        var generator = function() {
+            var results = [];
+
+            for (var i in illegalOperators) {
+                results.push({
+                    code: "var obj = { get " + illegalOperators[i] + "() { return test; }};",
+                    operator: illegalOperators[i],
+                    method: "get"
+                });
+                results.push({
+                    code: "var obj = { set " + illegalOperators[i] + "(value) { test = value}};",
+                    operator: illegalOperators[i],
+                    method: "set"
+                });
+                results.push({
+                    code: "var obj = { " + illegalOperators[i] + ': "123"};',
+                    operator: illegalOperators[i],
+                    method: "key"
+                });
+                results.push({
+                    code: "var obj = { " + illegalOperators[i] + "(){ return test; }};",
+                    operator: illegalOperators[i],
+                    method: "method"
+                });
+            }
+
+            return results;
+        };
+
+        var testCase = function(data) {
+            return function() {
+                Uglify.parse(data.code);
+            };
+        };
+
+        var fail = function(data) {
+            return function (e) {
+                return e instanceof Uglify.JS_Parse_Error && (
+                    e.message === "Unexpected token: operator (" + data.operator + ")" ||
+                    (e.message === "Unterminated regular expression" && data.operator[0] === "/") ||
+                    (e.message === "Unexpected token: punc (()" && data.operator === "*")
+                );
+            };
+        };
+
+        var errorMessage = function(data) {
+            return "Expected but didn't get a syntax error while parsing following line:\n" + data.code;
+        };
+
+        var tests = generator();
+        for (var i = 0; i < tests.length; i++) {
+            var test = tests[i];
+            assert.throws(testCase(test), fail(test), errorMessage(test));
+        }
+    });
+    it("Should be able to use shorthand properties", function() {
+        var ast = Uglify.parse("var foo = 123\nvar obj = {foo: foo}");
+        assert.strictEqual(ast.print_to_string({ecma: 6}), "var foo=123;var obj={foo};");
+    })
+});

test/mocha/release.js

@@ -1,20 +1,23 @@
 var assert = require("assert");
-var semver = require("semver");
 var spawn = require("child_process").spawn;
 
 if (!process.env.UGLIFYJS_TEST_ALL) return;
 
 function run(command, args, done) {
+    var id = setInterval(function() {
+        process.stdout.write("\0");
+    }, 5 * 60 * 1000);
     spawn(command, args, {
-        stdio: [ "ignore", 1, 2 ]
+        stdio: "ignore"
     }).on("exit", function(code) {
+        clearInterval(id);
         assert.strictEqual(code, 0);
         done();
     });
 }
 
 describe("test/benchmark.js", function() {
-    this.timeout(10 * 60 * 1000);
+    this.timeout(5 * 60 * 1000);
     [
         "-b",
         "-b bracketize",
@@ -33,9 +36,11 @@ describe("test/benchmark.js", function() {
     });
 });
 
-if (semver.satisfies(process.version, "0.12")) return;
 describe("test/jetstream.js", function() {
     this.timeout(20 * 60 * 1000);
+    it("Should install phantomjs-prebuilt", function(done) {
+        run("npm", ["install", "phantomjs-prebuilt@2.1.14"], done);
+    });
     [
         "-mc",
         "-mc keep_fargs=false,passes=3,pure_getters,unsafe,unsafe_comps,unsafe_math,unsafe_proto",
@@ -43,7 +48,6 @@ describe("test/jetstream.js", function() {
         it("Should pass with options " + options, function(done) {
             var args = options.split(/ /);
             args.unshift("test/jetstream.js");
-            args.push("-b", "beautify=false,webkit");
             run(process.argv[0], args, done);
         });
     });

test/mocha/spidermonkey.js

@@ -4,7 +4,7 @@ var uglify = require("../node");
 
 describe("spidermonkey export/import sanity test", function() {
     it("should produce a functional build when using --self with spidermonkey", function(done) {
-        this.timeout(60000);
+        this.timeout(30000);
 
         var uglifyjs = '"' + process.argv[0] + '" bin/uglifyjs';
         var command = uglifyjs + " --self -cm --wrap SpiderUglify -o spidermonkey | " +
@@ -15,9 +15,7 @@ describe("spidermonkey export/import sanity test", function() {
 
             eval(stdout);
             assert.strictEqual(typeof SpiderUglify, "object");
-            var result = SpiderUglify.minify("foo([true,,2+3]);");
-            assert.strictEqual(result.error, undefined);
-            assert.strictEqual(result.code, "foo([!0,,5]);");
+            assert.strictEqual(SpiderUglify.minify("foo([true,,2+3]);").code, "foo([!0,,5]);");
 
             done();
         });

test/mocha/template-string.js

@@ -0,0 +1,33 @@
+var assert = require("assert");
+var uglify = require("../node");
+
+describe("Template string", function() {
+    it("Should not accept invalid sequences", function() {
+        var tests = [
+            // Stress invalid expression
+            "var foo = `Hello ${]}`",
+            "var foo = `Test 123 ${>}`",
+            "var foo = `Blah ${;}`",
+
+            // Stress invalid template_substitution after expression
+            "var foo = `Blablabla ${123 456}`",
+            "var foo = `Blub ${123;}`",
+            "var foo = `Bleh ${a b}`"
+        ];
+
+        var exec = function(test) {
+            return function() {
+                uglify.parse(test);
+            }
+        };
+
+        var fail = function(e) {
+            return e instanceof uglify.JS_Parse_Error
+                && /^Unexpected token: /.test(e.message);
+        };
+
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(exec(tests[i]), fail, tests[i]);
+        }
+    });
+});

test/mocha/try.js

@@ -0,0 +1,22 @@
+var assert = require("assert");
+var uglify = require("../node");
+
+describe("Try", function() {
+    it("Should not allow catch with an empty parameter", function() {
+        var tests = [
+            "try {} catch() {}"
+        ];
+
+        var test = function(code) {
+            return function () {
+                uglify.parse(code);
+            }
+        }
+        var error = function (e) {
+            return e instanceof uglify.JS_Parse_Error;
+        }
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error, tests[i]);
+        }
+    });
+});