Merge pull request #1967 from alexlamsl/harmony-v3.0.8

Merging from master for 3.0.8

.github/ISSUE_TEMPLATE.md

@@ -8,14 +8,7 @@
 
 **Uglify version (`uglifyjs -V`)**
 
-**JavaScript input**
-
-<!--
-    A complete parsable JS program exhibiting the issue with
-    UglifyJS alone - without third party tools or libraries.
-    Ideally the input should be as small as possible.
-    Post a link to a gist if necessary.
--->
+**JavaScript input**  <!-- ideally as small as possible -->
 
 **The `uglifyjs` CLI command executed or `minify()` options used.**
 

.travis.yml

@@ -4,11 +4,8 @@ node_js:
     - "0.12"
     - "4"
     - "6"
-    - "8"
 env:
     - UGLIFYJS_TEST_ALL=1
 matrix:
   fast_finish: true
 sudo: false
-cache:
-  directories: tmp

README.md

@@ -1,14 +1,11 @@
-UglifyJS 3
-==========
+uglify-es
+=========
 
-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
 -------
@@ -18,11 +15,11 @@ 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
 
@@ -45,7 +42,6 @@ a double dash to prevent input files being used as option arguments:
 
 ```
     -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.
@@ -111,7 +107,7 @@ a double dash to prevent input files being used as option arguments:
                                 By default UglifyJS will not try to be IE-proof.
     --keep-fnames               Do not mangle/drop function names.  Useful for
                                 code relying on Function.prototype.name.
-    --name-cache <file>         File to hold mangled name mappings.
+    --name-cache                File to hold mangled name mappings.
     --self                      Build UglifyJS as a library (implies --wrap UglifyJS)
     --source-map [options]      Enable source map/specify source map options:
                                 `base`  Path to compute relative paths from input files.
@@ -127,8 +123,8 @@ 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
@@ -150,19 +146,19 @@ debugging your compressed JavaScript.  To get a source map, pass
 
 Additional options:
 
-- `--source-map "filename='<NAME>'"` to specify the name of the source map.
+- `--source-map filename=<NAME>` to specify the name of the source map.
 
-- `--source-map "root='<URL>'"` to pass the URL where the original files can be found.
+- `--source-map root=<URL>` to pass the URL where the original files can be found.
   Otherwise UglifyJS assumes HTTP `X-SourceMap` is being used and will omit the
   `//# sourceMappingURL=` directive.
 
-- `--source-map "url='<URL>'"` to specify the URL where the source map can be found.
+- `--source-map url=<URL>` to specify the URL where the source map can be found.
 
 For example:
 
     uglifyjs js/file1.js js/file2.js \
              -o foo.min.js -c -m \
-             --source-map "root='http://foo.com/src',url='foo.min.js.map'"
+             --source-map root="http://foo.com/src",url=foo.min.js.map
 
 The above will compress and mangle `file1.js` and `file2.js`, will drop the
 output in `foo.min.js` and the source map in `foo.min.js.map`.  The source
@@ -181,8 +177,8 @@ CoffeeScript → compiled JS, UglifyJS can generate a map from CoffeeScript →
 compressed JS by mapping every token in the compiled JS to its original
 location.
 
-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
+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
@@ -203,7 +199,7 @@ Example:
 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
@@ -213,60 +209,30 @@ When mangling is enabled but you want to prevent certain names from being
 mangled, you can declare those names with `--mangle reserved` — pass a
 comma-separated list of names.  For example:
 
-    uglifyjs ... -m reserved=['$','require','exports']
+    uglifyjs ... -m reserved=[$,require,exports]
 
 to prevent the `require`, `exports` and `$` names from being changed.
 
 ### CLI 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
 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 +241,7 @@ 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.
 
@@ -303,20 +269,9 @@ 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
@@ -327,13 +282,6 @@ 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
@@ -347,137 +295,30 @@ identify mistakes like writing mangled keys to storage.
 Assuming installation via NPM, you can load UglifyJS in your application
 like this:
 ```javascript
-var UglifyJS = require("uglify-js");
+var UglifyJS = require("uglify-es");
 ```
 
-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:
+There is a single high level minification function, `minify(files, options)`, which will
+performs all the steps in a configurable manner.
+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}
+var result = UglifyJS.minify("var b = function() {};");
+console.log(result.code);  // minified output
+console.log(result.error); // runtime error
 ```
 
-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:
+You can also compress multiple files:
 ```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);
+var result = UglifyJS.minify({
+    "file1.js": "var a = function() {};",
+    "file2.js": "var b = function() {};"
+});
 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(3+7);
-```
-
-The `nameCache` option:
-```javascript
-var options = {
-    mangle: {
-        toplevel: true,
-    },
-    nameCache: {}
-};
-var result1 = UglifyJS.minify({
-    "file1.js": "function add(first, second) { return first + second; }"
-}, options);
-var result2 = UglifyJS.minify({
-    "file2.js": "console.log(add(1 + 2, 3 + 4));"
-}, options);
-console.log(result1.code);
-// function n(n,r){return n+r}
-console.log(result2.code);
-// console.log(n(3,7));
-```
-
-You may persist the name cache to the file system in the following way:
-```javascript
-var cacheFileName = "/tmp/cache.json";
-var options = {
-    mangle: {
-        properties: true,
-    },
-    nameCache: JSON.parse(fs.readFileSync(cacheFileName, "utf8"))
-};
-fs.writeFileSync("part1.js", UglifyJS.minify({
-    "file1.js": fs.readFileSync("file1.js", "utf8"),
-    "file2.js": fs.readFileSync("file2.js", "utf8")
-}, options).code, "utf8");
-fs.writeFileSync("part2.js", UglifyJS.minify({
-    "file3.js": fs.readFileSync("file3.js", "utf8"),
-    "file4.js": fs.readFileSync("file4.js", "utf8")
-}, options).code, "utf8");
-fs.writeFileSync(cacheFileName, JSON.stringify(options.nameCache), "utf8");
-```
-
-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.
+- `warnings` (default `false`) — pass `true` to display compressor warnings.
 
 - `parse` (default `{}`) — pass an object if you wish to specify some
   additional [parse options](#parse-options).
@@ -501,16 +342,9 @@ if (result.error) throw result.error;
 - `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.
 
-- `nameCache` (default `null`) - pass an empty object `{}` or a previously
-  used `nameCache` object if you wish to cache mangled variable and
-  property names across multiple invocations of `minify()`. Note: this is
-  a read/write property. `minify()` will read the name cache state of this
-  object and update it during minification so that it may be
-  reused or externally persisted by the user.
-
 - `ie8` (default `false`) - set to `true` to support IE8.
 
-## Minify options structure
+## Minify option structure
 
 ```javascript
 {
@@ -534,7 +368,6 @@ if (result.error) throw result.error;
     sourceMap: {
         // source map options
     },
-    nameCache: null, // or specify a name cache object
     toplevel: false,
     ie8: false,
 }
@@ -620,18 +453,12 @@ 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
 
@@ -644,10 +471,6 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 - `booleans` -- various optimizations for boolean context, for example `!!a
   ? b : c → a ? b : c`
 
-- `typeofs` -- default `true`.  Transforms `typeof foo == "undefined"` into
-  `foo === void 0`.  Note: recommend to set this value to `false` for IE10 and
-  earlier versions due to known issues.
-
 - `loops` -- optimizations for `do`, `while` and `for` loops when we can
   statically determine the condition
 
@@ -655,7 +478,7 @@ 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`
@@ -668,15 +491,13 @@ 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.
@@ -721,7 +542,7 @@ 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`. The maximum number of times to run compress.
+- `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.
 
@@ -729,24 +550,23 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   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();`
+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"]`.
+- `reserved` - pass an array of identifiers that should be excluded from mangling
 
-- `toplevel` (default `false`). Pass `true` to mangle names declared in the
-  top level scope.
+- `toplevel` — mangle names declared in the toplevel scope (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](#compress-options).
+- `eval` — mangle names visible in scopes where eval or with are used
+(disabled by default).
 
-- `eval` (default `false`). Pass `true` to mangle names visible in scopes
-  where `eval` or `with` are used.
+- `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).
 
 Examples:
 
@@ -772,15 +592,10 @@ UglifyJS.minify(code, { mangle: { toplevel: true } }).code;
 
 ### 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.
+- `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.
 
 ## Output options
 
@@ -800,6 +615,9 @@ can pass additional arguments that control the code output:
 - `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.
+- `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.
 - `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
@@ -818,7 +636,7 @@ can pass additional arguments that control the code output:
 - `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.
+    more double quotes in the string itself.
   - `1` -- always use single quotes
   - `2` -- always use double quotes
   - `3` -- always use the original quotes
@@ -877,6 +695,7 @@ when this flag is on:
 - `new Object()` → `{}`
 - `String(exp)` or `exp.toString()` → `"" + exp`
 - `new Object/RegExp/Function/Error/Array (...)` → we discard the `new`
+- `typeof foo == "undefined"` → `foo === void 0`
 - `void 0` → `undefined` (if there is a variable named "undefined" in
   scope; we do it because the variable name will be mangled, typically
   reduced to a single character)
@@ -903,8 +722,8 @@ 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.
 ```
 
@@ -924,7 +743,7 @@ You can also use conditional compilation via the programmatic API. With the diff
 property name is `global_defs` and is a compressor property:
 
 ```javascript
-var result = UglifyJS.minify(fs.readFileSync("input.js", "utf8"), {
+var result = uglifyJS.minify(fs.readFileSync("input.js", "utf8"), {
     compress: {
         dead_code: true,
         global_defs: {
@@ -934,32 +753,6 @@ 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:
-```javascript
-UglifyJS.minify("alert('hello');", {
-    compress: {
-        global_defs: {
-            "@alert": "console.log"
-        }
-    }
-}).code;
-// returns: 'console.log("hello");'
-```
-
-Otherwise it would be replaced as string literal:
-```javascript
-UglifyJS.minify("alert('hello');", {
-    compress: {
-        global_defs: {
-            "alert": "console.log"
-        }
-    }
-}).code;
-// returns: '"console.log"("hello");'
-```
-
 ### Using native Uglify AST with `minify()`
 ```javascript
 // example: parse only, produce native Uglify AST
@@ -1029,30 +822,3 @@ in total it's a bit more than just using UglifyJS's own parser.
 
 [acorn]: https://github.com/ternjs/acorn
 [sm-spec]: https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k
-
-### Uglify Fast Minify Mode
-
-It's not well known, but whitespace removal and symbol mangling accounts
-for 95% of the size reduction in minified code for most javascript - not
-elaborate code transforms. One can simply disable `compress` to speed up
-Uglify builds by 3 to 4 times. In this fast `mangle`-only mode Uglify has
-comparable minify speeds and gzip sizes to
-[`butternut`](https://www.npmjs.com/package/butternut):
-
-| d3.js | minify size | gzip size | minify time (seconds) |
-| --- | ---: | ---: | ---: |
-| original | 451,131 | 108,733 | - |
-| uglify-js@3.0.24 mangle=false, compress=false | 316,600 | 85,245 | 0.70 |
-| uglify-js@3.0.24 mangle=true, compress=false | 220,216 | 72,730 | 1.13 |
-| butternut@0.4.6 | 217,568 | 72,738 | 1.41 |
-| uglify-js@3.0.24 mangle=true, compress=true | 212,511 | 71,560 | 3.36 |
-| babili@0.1.4 | 210,713 | 72,140 | 12.64 |
-
-To enable fast minify mode from the CLI use:
-```
-uglifyjs file.js -m
-```
-To enable fast minify mode with the API use:
-```js
-UglifyJS.minify(code, { compress: false, mangle: true });
-```

bin/uglifyjs

@@ -21,25 +21,14 @@ var options = {
     compress: false,
     mangle: false
 };
-program.version(info.name + " " + info.version);
+program.version(info.name + ' ' + 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());
-program.option("-c, --compress [options]", "Enable compressor/specify compressor options.", parse_js());
-program.option("-m, --mangle [options]", "Mangle names/specify mangler options.", parse_js());
-program.option("--mangle-props [options]", "Mangle properties/specify mangler options.", parse_js());
-program.option("-b, --beautify [options]", "Beautify output/specify output options.", parse_js());
+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));
+program.option("--mangle-props [options]", "Mangle properties/specify mangler options.", parse_js("mangle-props", true));
+program.option("-b, --beautify [options]", "Beautify output/specify output options.", parse_js("beautify", true));
 program.option("-o, --output <file>", "Output file (default STDOUT).");
 program.option("--comments [filter]", "Preserve copyright comments in the output.");
 program.option("--config-file <file>", "Read minify() options from JSON file.");
@@ -49,7 +38,7 @@ 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.");
@@ -106,8 +95,17 @@ if (program.mangleProps) {
     if (typeof options.mangle != "object") options.mangle = {};
     options.mangle.properties = program.mangleProps;
 }
+var cache;
 if (program.nameCache) {
-    options.nameCache = JSON.parse(read_file(program.nameCache, "{}"));
+    cache = JSON.parse(read_file(program.nameCache, "{}"));
+    if (options.mangle) {
+        if (typeof options.mangle != "object") options.mangle = {};
+        options.mangle.cache = to_cache("vars");
+        if (options.mangle.properties) {
+            if (typeof options.mangle.properties != "object") options.mangle.properties = {};
+            options.mangle.properties.cache = to_cache("props");
+        }
+    }
 }
 if (program.output == "ast") {
     options.output = {
@@ -116,10 +114,10 @@ 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) {
@@ -141,7 +139,7 @@ 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) {
@@ -171,9 +169,9 @@ 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) {
@@ -200,7 +198,7 @@ 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];
@@ -209,22 +207,21 @@ 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;
@@ -240,7 +237,7 @@ 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: {
@@ -254,19 +251,19 @@ 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(options.nameCache));
-    }
-    if (result.timings) for (var phase in result.timings) {
-        print_error("- " + phase + ": " + result.timings[phase].toFixed(3) + "s");
+        fs.writeFileSync(program.nameCache, JSON.stringify(cache, function(key, value) {
+            return value instanceof UglifyJS.Dictionary ? value.toObject() : value;
+        }));
     }
+    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);
 }
 
@@ -310,7 +307,7 @@ function read_file(path, default_value) {
     }
 }
 
-function parse_js(flag) {
+function parse_js(flag, constants) {
     return function(value, options) {
         options = options || {};
         try {
@@ -328,7 +325,7 @@ function parse_js(flag) {
                 if (node instanceof UglifyJS.AST_Assign) {
                     var name = node.left.print_to_string();
                     var value = node.right;
-                    if (flag) {
+                    if (!constants) {
                         options[name] = value;
                     } else if (value instanceof UglifyJS.AST_Array) {
                         options[name] = value.elements.map(to_string);
@@ -351,51 +348,37 @@ function parse_js(flag) {
                 }
             }));
         } catch(ex) {
-            if (flag) {
-                fatal("Error parsing arguments for '" + flag + "': " + value);
-            } else {
-                options[value] = null;
-            }
+            fatal("Error parsing arguments for '" + flag + "': " + value);
         }
         return options;
     }
 }
 
 function parse_source_map() {
-    var parse = parse_js();
+    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;
     }
 }
 
+function to_cache(key) {
+    if (cache[key]) {
+        cache[key].props = UglifyJS.Dictionary.fromObject(cache[key].props);
+    } else {
+        cache[key] = {
+            cname: -1,
+            props: new UglifyJS.Dictionary()
+        };
+    }
+    return 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

@@ -134,10 +134,11 @@ var AST_Debugger = DEFNODE("Debugger", null, {
     $documentation: "Represents a debugger statement",
 }, AST_Statement);
 
-var AST_Directive = DEFNODE("Directive", "value quote", {
+var AST_Directive = DEFNODE("Directive", "value scope quote", {
     $documentation: "Represents a directive, like \"use strict\";",
     $propdoc: {
         value: "[string] The value of this directive as a plain string (it's not an AST_String!)",
+        scope: "[AST_Scope/S] The scope that this directive affects",
         quote: "[string] the original quote character"
     },
 }, AST_Statement);
@@ -156,7 +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++) {
@@ -283,6 +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: {
@@ -298,9 +303,10 @@ var AST_With = DEFNODE("With", "expression", {
 
 /* -----[ scope and functions ]----- */
 
-var AST_Scope = DEFNODE("Scope", "variables functions uses_with uses_eval parent_scope enclosed cname", {
+var AST_Scope = DEFNODE("Scope", "directives variables functions uses_with uses_eval parent_scope enclosed cname", {
     $documentation: "Base class for all statements introducing a lexical scope",
     $propdoc: {
+        directives: "[string*/S] an array of directives declared in this scope",
         variables: "[Object/S] a map of name -> SymbolDef for all variables/functions defined in this scope",
         functions: "[Object/S] like `variables`, but only lists function declarations",
         uses_with: "[boolean/S] tells whether this scope uses the `with` statement",
@@ -309,6 +315,13 @@ var AST_Scope = DEFNODE("Scope", "variables functions uses_with uses_eval parent
         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", {
@@ -329,13 +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);
@@ -356,10 +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, {
@@ -479,7 +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(){
@@ -493,10 +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"
     },
@@ -514,10 +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) {
@@ -648,6 +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", {
@@ -683,11 +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.",
+        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_Accessor."
     },
     _walk: function(visitor) {
         return visitor._visit(this, function(){
+            if (this.key instanceof AST_Node)
+                this.key._walk(visitor);
             this.value._walk(visitor);
         });
     }
@@ -700,35 +950,94 @@ 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_SymbolAccessor = DEFNODE("SymbolAccessor", null, {
-    $documentation: "The name of a property accessor (setter/getter function)"
-}, AST_Symbol);
+var AST_NewTarget = DEFNODE("NewTarget", null, {
+    $documentation: "A reference to new.target"
+});
 
 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);
@@ -737,13 +1046,33 @@ 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)",
@@ -768,6 +1097,10 @@ 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() {
@@ -841,6 +1174,21 @@ 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) {
@@ -857,7 +1205,7 @@ TreeWalker.prototype = {
         if (!ret && descend) {
             descend.call(node);
         }
-        this.pop();
+        this.pop(node);
         return ret;
     },
     parent: function(n) {
@@ -868,11 +1216,17 @@ 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() {
-        if (this.stack.pop() instanceof AST_Lambda) {
+    pop: function(node) {
+        this.stack.pop();
+        if (node instanceof AST_Lambda || node instanceof AST_Class) {
             this.directives = Object.getPrototypeOf(this.directives);
         }
     },
@@ -890,7 +1244,7 @@ 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

@@ -27,73 +27,40 @@ function set_shorthand(name, options, keys) {
     }
 }
 
-function init_cache(cache) {
-    if (!cache) return;
-    if (!("cname" in cache)) cache.cname = -1;
-    if (!("props" in cache)) {
-        cache.props = new Dictionary();
-    } else if (!(cache.props instanceof Dictionary)) {
-        cache.props = Dictionary.fromObject(cache.props);
-    }
-}
-
-function to_json(cache) {
-    return {
-        cname: cache.cname,
-        props: cache.props.toObject()
-    };
-}
-
 function minify(files, options) {
     var warn_function = AST_Node.warn_function;
     try {
+        if (typeof files == "string") {
+            files = [ files ];
+        }
         options = defaults(options, {
             compress: {},
             ie8: false,
             keep_fnames: false,
             mangle: {},
-            nameCache: null,
             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" ]);
         set_shorthand("warnings", options, [ "compress" ]);
-        var quoted_props;
         if (options.mangle) {
             options.mangle = defaults(options.mangle, {
-                cache: options.nameCache && (options.nameCache.vars || {}),
+                cache: null,
                 eval: false,
                 ie8: false,
+                keep_classnames: false,
                 keep_fnames: false,
                 properties: false,
                 reserved: [],
+                safari10: false,
                 toplevel: false,
             }, true);
-            if (options.mangle.properties) {
-                if (typeof options.mangle.properties != "object") {
-                    options.mangle.properties = {};
-                }
-                if (options.mangle.properties.keep_quoted) {
-                    quoted_props = options.mangle.properties.reserved;
-                    if (!Array.isArray(quoted_props)) quoted_props = [];
-                    options.mangle.properties.reserved = quoted_props;
-                }
-                if (options.nameCache && !("cache" in options.mangle.properties)) {
-                    options.mangle.properties.cache = options.nameCache.props || {};
-                }
-            }
-            init_cache(options.mangle.cache);
-            init_cache(options.mangle.properties.cache);
         }
         if (options.sourceMap) {
             options.sourceMap = defaults(options.sourceMap, {
@@ -110,17 +77,13 @@ 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") {
@@ -131,29 +94,22 @@ function minify(files, options) {
             }
             toplevel = options.parse.toplevel;
         }
-        if (quoted_props) {
-            reserve_quoted_keys(toplevel, quoted_props);
-        }
         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;
@@ -169,9 +125,7 @@ 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]);
                     }
                 }
@@ -190,24 +144,6 @@ function minify(files, options) {
                 }
             }
         }
-        if (options.nameCache && options.mangle) {
-            if (options.mangle.cache) options.nameCache.vars = to_json(options.mangle.cache);
-            if (options.mangle.properties && options.mangle.properties.cache) {
-                options.nameCache.props = to_json(options.mangle.properties.cache);
-            }
-        }
-        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

@@ -118,7 +118,7 @@
                 value    : from_moz(M.value)
             };
             if (M.kind == "init") return new AST_ObjectKeyVal(args);
-            args.key = new AST_SymbolAccessor({
+            args.key = new AST_SymbolMethod({
                 name: args.key
             });
             args.value = new AST_Accessor(args.value);
@@ -168,7 +168,7 @@
             });
         },
         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 +204,7 @@
         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
@@ -324,7 +324,7 @@
     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)
         };
     });
@@ -381,7 +381,7 @@
     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
+            value: M.key instanceof AST_SymbolMethod ? M.key.name : M.key
         };
         var kind;
         if (M instanceof AST_ObjectKeyVal) {

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 +71,18 @@ function OutputStream(options) {
         quote_style      : 0,
         semicolons       : true,
         shebang          : true,
+        shorthand        : undefined,
         source_map       : null,
-        webkit           : 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) {
@@ -109,10 +117,20 @@ function OutputStream(options) {
     var current_pos = 0;
     var OUTPUT = "";
 
-    var to_utf8 = options.ascii_only ? function(str, identifier) {
-        return str.replace(/[\u0000-\u001f\u007f-\uffff]/g, function(ch) {
-            var code = ch.charCodeAt(0).toString(16);
-            if (code.length <= 2 && !identifier) {
+    function to_ascii(str, 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 {
@@ -120,12 +138,6 @@ function OutputStream(options) {
                 return "\\u" + code;
             }
         });
-    } : function(str) {
-        return str.replace(/[\ud800-\udbff](?![\udc00-\udfff])/g, function(ch) {
-            return "\\u" + ch.charCodeAt(0).toString(16);
-        }).replace(/(^|[^\ud800-\udbff])([\udc00-\udfff])/g, function(match, prefix, ch) {
-            return prefix + "\\u" + ch.charCodeAt(0).toString(16);
-        });
     };
 
     function make_string(str, quote) {
@@ -146,7 +158,7 @@ function OutputStream(options) {
               case "\u2029": return "\\u2029";
               case "\ufeff": return "\\ufeff";
               case "\0":
-                  return /[0-9]/.test(str.charAt(i+1)) ? "\\x00" : "\\0";
+                  return /[0-7]/.test(get_full_char(str, i+1)) ? "\\x00" : "\\0";
             }
             return s;
         });
@@ -156,7 +168,11 @@ function OutputStream(options) {
         function quote_double() {
             return '"' + str.replace(/\x22/g, '\\"') + '"';
         }
-        str = to_utf8(str);
+        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();
@@ -181,7 +197,8 @@ function OutputStream(options) {
 
     function make_name(name) {
         name = name.toString();
-        name = to_utf8(name, true);
+        if (options.ascii_identifiers)
+            name = to_ascii(name, true);
         return name;
     };
 
@@ -195,43 +212,12 @@ 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++;
@@ -241,18 +227,15 @@ 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;
 
@@ -304,18 +287,6 @@ 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;
@@ -328,6 +299,10 @@ function OutputStream(options) {
         last = str;
     };
 
+    var star = function(){
+        print("*");
+    }
+
     var space = options.beautify ? function() {
         print(" ");
     } : function() {
@@ -410,9 +385,24 @@ function OutputStream(options) {
         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() {
@@ -432,13 +422,14 @@ 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,
         last            : function() { return last },
         semicolon       : semicolon,
         force_semicolon : force_semicolon,
-        to_utf8         : to_utf8,
+        to_ascii        : to_ascii,
         print_name      : function(name) { print(make_name(name)) },
         print_string    : function(str, quote, escape_directive) {
             var encoded = encode_string(str, quote);
@@ -451,6 +442,10 @@ 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,
@@ -482,17 +477,13 @@ function OutputStream(options) {
         nodetype.DEFMETHOD("_codegen", generator);
     };
 
+    var use_asm = false;
     var in_directive = false;
-    var active_scope = null;
-    var use_asm = null;
 
     AST_Node.DEFMETHOD("print", function(stream, force_parens){
-        var self = this, generator = self._codegen;
-        if (self instanceof AST_Scope) {
-            active_scope = self;
-        }
-        else if (!use_asm && self instanceof AST_Directive && self.value == "use asm") {
-            use_asm = active_scope;
+        var self = this, generator = self._codegen, prev_use_asm = use_asm;
+        if (self instanceof AST_Directive && self.value == "use asm" && stream.parent() instanceof AST_Scope) {
+            use_asm = true;
         }
         function doit() {
             self.add_comments(stream);
@@ -506,11 +497,10 @@ function OutputStream(options) {
             doit();
         }
         stream.pop_node();
-        if (self === use_asm) {
-            use_asm = null;
+        if (self instanceof AST_Scope) {
+            use_asm = prev_use_asm;
         }
     });
-    AST_Node.DEFMETHOD("_print", AST_Node.prototype.print);
 
     AST_Node.DEFMETHOD("print_to_string", function(options){
         var s = OutputStream(options);
@@ -608,13 +598,6 @@ 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;
@@ -623,6 +606,11 @@ 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){
@@ -632,20 +620,28 @@ 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(){}))
         ;
     });
 
@@ -672,6 +668,24 @@ 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) {
@@ -681,15 +695,14 @@ function OutputStream(options) {
             // parens around it too, otherwise the call will be
             // interpreted as passing the arguments to the upper New
             // expression.
-            var parens = false;
-            this.walk(new TreeWalker(function(node) {
-                if (parens || node instanceof AST_Scope) return true;
-                if (node instanceof AST_Call) {
-                    parens = true;
-                    return true;
-                }
-            }));
-            return parens;
+            try {
+                this.walk(new TreeWalker(function(node){
+                    if (node instanceof AST_Call) throw p;
+                }));
+            } catch(ex) {
+                if (ex !== p) throw ex;
+                return true;
+            }
         }
     });
 
@@ -742,6 +755,9 @@ 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 ]----- */
@@ -750,6 +766,28 @@ 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();
@@ -874,7 +912,11 @@ 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);
         });
@@ -896,10 +938,19 @@ 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){
@@ -914,6 +965,56 @@ 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);
@@ -930,6 +1031,17 @@ 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);
@@ -1078,22 +1190,122 @@ 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) {
-        var parens = false;
-        // need to take some precautions here:
-        //    https://github.com/mishoo/UglifyJS2/issues/60
-        if (noin) node.walk(new TreeWalker(function(node) {
-            if (parens || node instanceof AST_Scope) return true;
-            if (node instanceof AST_Binary && node.operator == "in") {
-                parens = true;
-                return true;
-            }
-        }));
-        node.print(output, parens);
+        if (!noin) node.print(output);
+        else try {
+            // need to take some precautions here:
+            //    https://github.com/mishoo/UglifyJS2/issues/60
+            node.walk(new TreeWalker(function(node){
+                if (node instanceof AST_Binary && node.operator == "in")
+                    throw output;
+            }));
+            node.print(output);
+        } catch(ex) {
+            if (ex !== output) throw ex;
+            node.print(output, true);
+        }
     };
 
     DEFPRINT(AST_VarDef, function(self, output){
@@ -1113,9 +1325,6 @@ function OutputStream(options) {
         self.expression.print(output);
         if (self instanceof AST_New && !need_constructor_parens(self, output))
             return;
-        if (self.expression instanceof AST_Call || self.expression instanceof AST_Lambda) {
-            output.add_mapping(self.start);
-        }
         output.with_parens(function(){
             self.args.forEach(function(expr, i){
                 if (i) output.comma();
@@ -1155,23 +1364,15 @@ function OutputStream(options) {
     DEFPRINT(AST_Dot, function(self, output){
         var expr = self.expression;
         expr.print(output);
-        var prop = self.property;
-        if (output.option("ie8") && RESERVED_WORDS(prop)) {
-            output.print("[");
-            output.add_mapping(self.end);
-            output.print_string(prop);
-            output.print("]");
-        } else {
-            if (expr instanceof AST_Number && expr.getValue() >= 0) {
-                if (!/[xa-f.)]/i.test(output.last())) {
-                    output.print(".");
-                }
+        if (expr instanceof AST_Number && expr.getValue() >= 0) {
+            if (!/[xa-f.)]/i.test(output.last())) {
+                output.print(".");
             }
-            output.print(".");
-            // the name after dot would be mapped about here.
-            output.add_mapping(self.end);
-            output.print_name(prop);
         }
+        output.print(".");
+        // the name after dot would be mapped about here.
+        output.add_mapping(self.end);
+        output.print_name(self.property);
     });
     DEFPRINT(AST_Sub, function(self, output){
         self.expression.print(output);
@@ -1262,8 +1463,49 @@ 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) {
+            var parens = (
+                   !(self.extends instanceof AST_SymbolRef)
+                && !(self.extends instanceof AST_PropAccess)
+                && !(self.extends instanceof AST_ClassExpression)
+                && !(self.extends instanceof AST_Function)
+            );
+            output.print("extends");
+            if (parens) {
+                output.print("(");
+            } else {
+                output.space();
+            }
+            self.extends.print(output);
+            if (parens) {
+                output.print(")");
+            } else {
+                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"
@@ -1280,33 +1522,98 @@ 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());
     });
@@ -1327,7 +1634,9 @@ function OutputStream(options) {
         if (regexp.raw_source) {
             str = "/" + regexp.raw_source + str.slice(str.lastIndexOf("/"));
         }
-        str = output.to_utf8(str);
+        if (output.option("ascii_only")) {
+            str = output.to_ascii(str);
+        }
         output.print(str);
         var p = output.parent();
         if (p instanceof AST_Binary && /^in/.test(p.operator) && p.left === self)

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) {
@@ -67,34 +85,6 @@ function find_builtins(reserved) {
     }
 }
 
-function reserve_quoted_keys(ast, reserved) {
-    function add(name) {
-        push_uniq(reserved, name);
-    }
-
-    ast.walk(new TreeWalker(function(node) {
-        if (node instanceof AST_ObjectKeyVal && node.quote) {
-            add(node.key);
-        } else if (node instanceof AST_Sub) {
-            addStrings(node.property, add);
-        }
-    }));
-}
-
-function addStrings(node, add) {
-    node.walk(new TreeWalker(function(node) {
-        if (node instanceof AST_Sequence) {
-            addStrings(node.expressions[node.expressions.length - 1], add);
-        } else if (node instanceof AST_String) {
-            add(node.value);
-        } else if (node instanceof AST_Conditional) {
-            addStrings(node.consequent, add);
-            addStrings(node.alternative, add);
-        }
-        return true;
-    }));
-}
-
 function mangle_properties(ast, options) {
     options = defaults(options, {
         builtins: false,
@@ -104,10 +94,9 @@ function mangle_properties(ast, options) {
         only_cache: false,
         regex: null,
         reserved: null,
-    }, true);
+    });
 
-    var reserved = options.reserved;
-    if (!Array.isArray(reserved)) reserved = [];
+    var reserved = options.reserved || [];
     if (!options.builtins) find_builtins(reserved);
 
     var cache = options.cache;
@@ -119,6 +108,7 @@ function mangle_properties(ast, options) {
     }
 
     var regex = options.regex;
+    var keep_quoted = options.keep_quoted;
 
     // note debug is either false (disabled), or a string of the debug suffix to use (enabled).
     // note debug may be enabled as an empty string, which is falsey. Also treat passing 'true'
@@ -131,11 +121,12 @@ function mangle_properties(ast, options) {
 
     var names_to_mangle = [];
     var unmangleable = [];
+    var to_keep = {};
 
     // step 1: find candidates to mangle
     ast.walk(new TreeWalker(function(node){
         if (node instanceof AST_ObjectKeyVal) {
-            add(node.key);
+            add(node.key, keep_quoted && node.quote);
         }
         else if (node instanceof AST_ObjectProperty) {
             // setter or getter, since KeyVal is handled above
@@ -145,14 +136,18 @@ function mangle_properties(ast, options) {
             add(node.property);
         }
         else if (node instanceof AST_Sub) {
-            addStrings(node.property, add);
+            addStrings(node.property, keep_quoted);
+        }
+        else if (node instanceof AST_ConciseMethod) {
+            add(node.name.name);
         }
     }));
 
     // step 2: transform the tree, renaming properties
     return ast.transform(new TreeTransformer(function(node){
         if (node instanceof AST_ObjectKeyVal) {
-            node.key = mangle(node.key);
+            if (!(keep_quoted && node.quote))
+                node.key = mangle(node.key);
         }
         else if (node instanceof AST_ObjectProperty) {
             // setter or getter
@@ -161,9 +156,27 @@ function mangle_properties(ast, options) {
         else if (node instanceof AST_Dot) {
             node.property = mangle(node.property);
         }
-        else if (!options.keep_quoted && node instanceof AST_Sub) {
-            node.property = mangleStrings(node.property);
+        else if (node instanceof AST_Sub) {
+            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(
+        //             "Found \"{prop}\" property candidate for mangling in an arbitrary string [{file}:{line},{col}]", {
+        //                 file : node.start.file,
+        //                 line : node.start.line,
+        //                 col  : node.start.col,
+        //                 prop : node.value
+        //             }
+        //         );
+        //     }
+        // }
     }));
 
     // only function declarations after this line
@@ -179,13 +192,19 @@ function mangle_properties(ast, options) {
     }
 
     function should_mangle(name) {
+        if (keep_quoted && name in to_keep) return false;
         if (regex && !regex.test(name)) return false;
         if (reserved.indexOf(name) >= 0) return false;
         return cache.props.has(name)
             || names_to_mangle.indexOf(name) >= 0;
     }
 
-    function add(name) {
+    function add(name, keep) {
+        if (keep) {
+            to_keep[name] = true;
+            return;
+        }
+
         if (can_mangle(name))
             push_uniq(names_to_mangle, name);
 
@@ -205,16 +224,19 @@ function mangle_properties(ast, options) {
                 // debug mode: use a prefix and suffix to preserve readability, e.g. o.foo -> o._$foo$NNN_.
                 var debug_mangled = "_$" + name + "$" + debug_name_suffix + "_";
 
-                if (can_mangle(debug_mangled)) {
+                if (can_mangle(debug_mangled) && !(keep_quoted && debug_mangled in to_keep)) {
                     mangled = debug_mangled;
                 }
             }
 
             // either debug mode is off, or it is on and we could not use the mangled name
             if (!mangled) {
+                // Note: `can_mangle()` does not check if the name collides with the `to_keep` set
+                // (filled with quoted properties when `keep_quoted` is set). Make sure we add this
+                // check so we don't collide with a quoted name.
                 do {
                     mangled = base54(++cache.cname);
-                } while (!can_mangle(mangled));
+                } while (!can_mangle(mangled) || keep_quoted && mangled in to_keep);
             }
 
             cache.props.set(name, mangled);
@@ -222,6 +244,32 @@ function mangle_properties(ast, options) {
         return mangled;
     }
 
+    function addStrings(node, keep) {
+        var out = {};
+        try {
+            (function walk(node){
+                node.walk(new TreeWalker(function(node){
+                    if (node instanceof AST_Sequence) {
+                        walk(node.expressions[node.expressions.length - 1]);
+                        return true;
+                    }
+                    if (node instanceof AST_String) {
+                        add(node.value, keep);
+                        return true;
+                    }
+                    if (node instanceof AST_Conditional) {
+                        walk(node.consequent);
+                        walk(node.alternative);
+                        return true;
+                    }
+                    throw out;
+                }));
+            })(node);
+        } catch(ex) {
+            if (ex !== out) throw ex;
+        }
+    }
+
     function mangleStrings(node) {
         return node.transform(new TreeTransformer(function(node){
             if (node instanceof AST_Sequence) {

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;
@@ -79,7 +87,7 @@ SymbolDef.prototype = {
             if (options.ie8 && sym instanceof AST_SymbolLambda)
                 s = s.parent_scope;
             var def;
-            if (def = this.redefined()) {
+            if (this.defun && (def = this.defun.variables.get(this.name))) {
                 this.mangled_name = def.mangled_name || def.name;
             } else
                 this.mangled_name = s.next_mangled(options, this);
@@ -87,9 +95,6 @@ SymbolDef.prototype = {
                 cache.set(this.name, this.mangled_name);
             }
         }
-    },
-    redefined: function() {
-        return this.defun && this.defun.variables.get(this.name);
     }
 };
 
@@ -97,6 +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
@@ -104,15 +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;
@@ -126,6 +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)) {
@@ -144,12 +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
@@ -157,10 +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);
@@ -171,7 +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);
@@ -186,8 +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;
@@ -200,25 +279,16 @@ 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);
             return true;
         }
-        // ensure mangling works if catch reuses a scope variable
-        var def;
-        if (node instanceof AST_SymbolCatch && (def = node.definition().redefined())) {
-            var s = node.scope;
-            while (s) {
-                push_uniq(s.enclosed, def);
-                if (s === def.scope) break;
-                s = s.parent_scope;
-            }
-        }
     });
     self.walk(tw);
 
@@ -235,12 +305,24 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
                     ref.reference(options);
                 });
                 node.thedef = def;
-                node.reference(options);
                 return true;
             }
         }));
     }
 
+    // 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;
     }
@@ -269,10 +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
@@ -305,16 +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);
@@ -363,17 +470,31 @@ AST_Function.DEFMETHOD("next_mangled", function(options, def){
 
 AST_Symbol.DEFMETHOD("unmangleable", function(options){
     var def = this.definition();
-    return !def || def.unmangleable(options);
+    return def && def.unmangleable(options);
 });
 
 // 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
         && !(this.scope.uses_eval || this.scope.uses_with);
 });
 
+AST_Symbol.DEFMETHOD("undeclared", function(){
+    return this.definition().undeclared;
+});
+
+AST_LabelRef.DEFMETHOD("undeclared", function(){
+    return false;
+});
+
+AST_Label.DEFMETHOD("undeclared", function(){
+    return false;
+});
+
 AST_Symbol.DEFMETHOD("definition", function(){
     return this.thedef;
 });
@@ -383,15 +504,14 @@ 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){
@@ -439,13 +559,19 @@ 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;
@@ -454,69 +580,111 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options){
 
 AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options){
     options = this._default_mangler_options(options);
-    try {
-        AST_Node.prototype.print = function(stream, force_parens) {
-            this._print(stream, force_parens);
-            if (this instanceof AST_Symbol && !this.unmangleable(options)) {
-                base54.consider(this.name, -1);
-            } else if (options.properties) {
-                if (this instanceof AST_Dot) {
-                    base54.consider(this.property, -1);
-                } else if (this instanceof AST_Sub) {
-                    skip_string(this.property);
-                }
-            }
-        };
-        base54.consider(this.print_to_string(), 1);
-    } finally {
-        AST_Node.prototype.print = AST_Node.prototype._print;
-    }
-    base54.sort();
-
-    function skip_string(node) {
-        if (node instanceof AST_String) {
-            base54.consider(node.value, -1);
-        } else if (node instanceof AST_Conditional) {
-            skip_string(node.consequent);
-            skip_string(node.alternative);
-        } else if (node instanceof AST_Sequence) {
-            skip_string(node.expressions[node.expressions.length - 1]);
+    var tw = new TreeWalker(function(node){
+        if (node instanceof AST_Constant)
+            base54.consider(node.print_to_string());
+        else if (node instanceof AST_Return)
+            base54.consider("return");
+        else if (node instanceof AST_Throw)
+            base54.consider("throw");
+        else if (node instanceof AST_Continue)
+            base54.consider("continue");
+        else if (node instanceof AST_Break)
+            base54.consider("break");
+        else if (node instanceof AST_Debugger)
+            base54.consider("debugger");
+        else if (node instanceof AST_Directive)
+            base54.consider(node.value);
+        else if (node instanceof AST_While)
+            base54.consider("while");
+        else if (node instanceof AST_Do)
+            base54.consider("do while");
+        else if (node instanceof AST_If) {
+            base54.consider("if");
+            if (node.alternative) base54.consider("else");
         }
-    }
+        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)
+            base54.consider("for");
+        else if (node instanceof AST_ForIn)
+            base54.consider("for in");
+        else if (node instanceof AST_Switch)
+            base54.consider("switch");
+        else if (node instanceof AST_Case)
+            base54.consider("case");
+        else if (node instanceof AST_Default)
+            base54.consider("default");
+        else if (node instanceof AST_With)
+            base54.consider("with");
+        else if (node instanceof AST_ObjectSetter)
+            base54.consider("set" + (typeof node.key === "string" ? node.key : ""));
+        else if (node instanceof AST_ObjectGetter)
+            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)
+            base54.consider(node.operator);
+        else if (node instanceof AST_Dot)
+            base54.consider(node.property);
+    });
+    this.walk(tw);
+    base54.sort();
 });
 
 var base54 = (function() {
-    var leading = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_".split("");
-    var digits = "0123456789".split("");
+    var string = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_0123456789";
     var chars, frequency;
     function reset() {
         frequency = Object.create(null);
-        leading.forEach(function(ch) {
-            frequency[ch] = 0;
-        });
-        digits.forEach(function(ch) {
-            frequency[ch] = 0;
-        });
+        chars = string.split("").map(function(ch){ return ch.charCodeAt(0) });
+        chars.forEach(function(ch){ frequency[ch] = 0 });
     }
-    base54.consider = function(str, delta) {
+    base54.consider = function(str){
         for (var i = str.length; --i >= 0;) {
-            frequency[str[i]] += delta;
+            var code = str.charCodeAt(i);
+            if (code in frequency) ++frequency[code];
         }
     };
-    function compare(a, b) {
-        return frequency[b] - frequency[a];
-    }
     base54.sort = function() {
-        chars = mergeSort(leading, compare).concat(mergeSort(digits, compare));
+        chars = mergeSort(chars, function(a, b){
+            if (is_digit(a) && !is_digit(b)) return 1;
+            if (is_digit(b) && !is_digit(a)) return -1;
+            return frequency[b] - frequency[a];
+        });
     };
     base54.reset = reset;
     reset();
+    base54.get = function(){ return chars };
+    base54.freq = function(){ return frequency };
     function base54(num) {
         var ret = "", base = 54;
         num++;
         do {
             num--;
-            ret += chars[num % base];
+            ret += String.fromCharCode(chars[num % base]);
             num = Math.floor(num / base);
             base = 64;
         } while (num > 0);

lib/transform.js

@@ -70,7 +70,7 @@ TreeTransformer.prototype = new TreeWalker;
                     if (y !== undefined) x = y;
                 }
             }
-            tw.pop();
+            tw.pop(this);
             return x;
         });
     };
@@ -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 +223,36 @@ 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_Export, function(self, tw){
+        if (self.exported_value) self.exported_value = self.exported_value.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",
+  "homepage": "https://github.com/mishoo/UglifyJS2/tree/harmony",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.1.2",
+  "version": "3.0.8",
   "engines": {
     "node": ">=0.8.0"
   },
@@ -29,16 +29,16 @@
     "LICENSE"
   ],
   "dependencies": {
-    "commander": "~2.11.0",
+    "commander": "~2.9.0",
     "source-map": "~0.5.1"
   },
   "devDependencies": {
-    "acorn": "~5.1.1",
-    "mocha": "~3.5.1",
-    "semver": "~5.4.1"
+    "acorn": "~5.0.3",
+    "mocha": "~2.3.4",
+    "semver": "~5.3.0"
   },
   "scripts": {
     "test": "node test/run-tests.js"
   },
-  "keywords": ["uglify", "uglify-js", "minify", "minifier", "es5"]
+  "keywords": ["uglify", "uglify-js", "minify", "minifier"]
 }

test/benchmark.js

@@ -4,14 +4,12 @@
 "use strict";
 
 var createHash = require("crypto").createHash;
-var fetch = require("./fetch");
 var fork = require("child_process").fork;
-var zlib = require("zlib");
 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",
@@ -31,10 +29,14 @@ 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("GZipped: ", info.gzip, "bytes");
             console.log("SHA1 sum:", info.sha1);
             if (info.code) {
                 failures.push(url);
@@ -53,21 +55,15 @@ urls.forEach(function(url) {
     results[url] = {
         input: 0,
         output: 0,
-        gzip: 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;
         }).pipe(uglifyjs.stdin);
         uglifyjs.stdout.on("data", function(data) {
             results[url].output += data.length;
-        }).pipe(zlib.createGzip({
-            level: zlib.Z_BEST_COMPRESSION
-        })).on("data", function(data) {
-            results[url].gzip += data.length;
         }).pipe(createHash("sha1")).on("data", function(data) {
             results[url].sha1 = data.toString("hex");
             done();

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/ascii.js

@@ -13,7 +13,7 @@ ascii_only_true: {
                    "\x20\x21\x22\x23 ... \x7d\x7e\x7f\x80\x81 ... \xfe\xff\u0fff\uffff";
         }
     }
-    expect_exact: 'function f(){return"\\x000\\x001\\x007\\x008\\0"+"\\0\\x01\\x02\\x03\\x04\\x05\\x06\\x07\\b\\t\\n\\v\\f\\r\\x0e\\x0f"+"\\x10\\x11\\x12\\x13\\x14\\x15\\x16\\x17\\x18\\x19\\x1a\\x1b\\x1c\\x1d\\x1e\\x1f"+\' !"# ... }~\\x7f\\x80\\x81 ... \\xfe\\xff\\u0fff\\uffff\'}'
+    expect_exact: 'function f(){return"\\x000\\x001\\x007\\08\\0"+"\\0\\x01\\x02\\x03\\x04\\x05\\x06\\x07\\b\\t\\n\\v\\f\\r\\x0e\\x0f"+"\\x10\\x11\\x12\\x13\\x14\\x15\\x16\\x17\\x18\\x19\\x1a\\x1b\\x1c\\x1d\\x1e\\x1f"+\' !"# ... }~\\x7f\\x80\\x81 ... \\xfe\\xff\\u0fff\\uffff\'}'
 }
 
 ascii_only_false: {
@@ -31,5 +31,5 @@ ascii_only_false: {
                    "\x20\x21\x22\x23 ... \x7d\x7e\x7f\x80\x81 ... \xfe\xff\u0fff\uffff";
         }
     }
-    expect_exact: 'function f(){return"\\x000\\x001\\x007\\x008\\0"+"\\0\x01\x02\x03\x04\x05\x06\x07\\b\\t\\n\\v\\f\\r\x0e\x0f"+"\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f"+\' !"# ... }~\x7f\x80\x81 ... \xfe\xff\u0fff\uffff\'}'
+    expect_exact: 'function f(){return"\\x000\\x001\\x007\\08\\0"+"\\0\x01\x02\x03\x04\x05\x06\x07\\b\\t\\n\\v\\f\\r\x0e\x0f"+"\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f"+\' !"# ... }~\x7f\x80\x81 ... \xfe\xff\u0fff\uffff\'}'
 }

test/compress/asm.js

@@ -104,65 +104,3 @@ asm_mixed: {
     }
 }
 
-asm_toplevel: {
-    options = {}
-    input: {
-        "use asm";
-        0.0;
-        function f() {
-            0.0;
-            (function(){
-                0.0;
-            });
-        }
-        0.0;
-    }
-    expect_exact: '"use asm";0.0;function f(){0.0;(function(){0.0})}0.0;'
-}
-
-asm_function_expression: {
-    options = {}
-    input: {
-        0.0;
-        var a = function() {
-            "use asm";
-            0.0;
-        }
-        function f() {
-            0.0;
-            return function(){
-                "use asm";
-                0.0;
-            }
-            0.0;
-        }
-        0.0;
-    }
-    expect_exact: '0;var a=function(){"use asm";0.0};function f(){0;return function(){"use asm";0.0};0}0;'
-}
-
-asm_nested_functions: {
-    options = {}
-    input: {
-        0.0;
-        function a() {
-            "use asm";
-            0.0;
-        }
-        0.0;
-        function b() {
-            0.0;
-            function c(){
-                "use asm";
-                0.0;
-            }
-            0.0;
-            function d(){
-                0.0;
-            }
-            0.0;
-        }
-        0.0;
-    }
-    expect_exact: '0;function a(){"use asm";0.0}0;function b(){0;function c(){"use asm";0.0}0;function d(){0}0}0;'
-}

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) }
@@ -863,7 +863,7 @@ collapse_vars_unary: {
     input: {
         function f0(o, p) {
             var x = o[p];
-            return delete x;
+            delete x;
         }
         function f1(n) {
             var k = !!n;
@@ -893,7 +893,7 @@ collapse_vars_unary: {
     expect: {
         function f0(o, p) {
             var x = o[p];
-            return delete x;
+            delete x;
         }
         function f1(n) {
             return n > +!!n
@@ -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,
@@ -1978,10 +2077,10 @@ chained_3: {
     }
     expect: {
         console.log(function(a, b) {
-            var c = 1, c = b;
+            var c = a, c = b;
             b++;
             return c;
-        }(0, 2));
+        }(1, 2));
     }
     expect_stdout: "2"
 }
@@ -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);
     }
@@ -2187,337 +2285,48 @@ compound_assignment: {
     expect_stdout: "4"
 }
 
-issue_2187_1: {
+reassign_const_1: {
     options = {
         collapse_vars: true,
-        unused: true,
     }
     input: {
-        var a = 1;
-        !function(foo) {
-            foo();
-            var a = 2;
-            console.log(a);
-        }(function() {
-            console.log(a);
-        });
-    }
-    expect: {
-        var a = 1;
-        !function(foo) {
-            foo();
-            var a = 2;
-            console.log(a);
-        }(function() {
-            console.log(a);
-        });
-    }
-    expect_stdout: [
-        "1",
-        "2",
-    ]
-}
-
-issue_2187_2: {
-    options = {
-        collapse_vars: true,
-        unused: true,
-    }
-    input: {
-        var b = 1;
-        console.log(function(a) {
-            return a && ++b;
-        }(b--));
-    }
-    expect: {
-        var b = 1;
-        console.log(function(a) {
-            return b-- && ++b;
-        }());
-    }
-    expect_stdout: "1"
-}
-
-issue_2187_3: {
-    options = {
-        collapse_vars: true,
-        inline: true,
-        unused: true,
-    }
-    input: {
-        var b = 1;
-        console.log(function(a) {
-            return a && ++b;
-        }(b--));
-    }
-    expect: {
-        var b = 1;
-        console.log(b-- && ++b);
-    }
-    expect_stdout: "1"
-}
-
-issue_2203_1: {
-    options = {
-        collapse_vars: true,
-        unused: true,
-    }
-    input: {
-        a = "FAIL";
-        console.log({
-            a: "PASS",
-            b: function() {
-                return function(c) {
-                    return c.a;
-                }((String, (Object, this)));
-            }
-        }.b());
-    }
-    expect: {
-        a = "FAIL";
-        console.log({
-            a: "PASS",
-            b: function() {
-                return function(c) {
-                    return c.a;
-                }((String, (Object, this)));
-            }
-        }.b());
-    }
-    expect_stdout: "PASS"
-}
-
-issue_2203_2: {
-    options = {
-        collapse_vars: true,
-        unused: true,
-    }
-    input: {
-        a = "PASS";
-        console.log({
-            a: "FAIL",
-            b: function() {
-                return function(c) {
-                    return c.a;
-                }((String, (Object, function() {
-                    return this;
-                }())));
-            }
-        }.b());
-    }
-    expect: {
-        a = "PASS";
-        console.log({
-            a: "FAIL",
-            b: function() {
-                return function(c) {
-                    return (String, (Object, function() {
-                        return this;
-                    }())).a;
-                }();
-            }
-        }.b());
-    }
-    expect_stdout: "PASS"
-}
-
-duplicate_argname: {
-    options = {
-        collapse_vars: true,
-        unused: true,
-    }
-    input: {
-        function f() { return "PASS"; }
-        console.log(function(a, a) {
-            f++;
+        function f() {
+            const a = 1;
+            a = 2;
             return a;
-        }("FAIL", f()));
-    }
-    expect: {
-        function f() { return "PASS"; }
-        console.log(function(a, a) {
-            f++;
-            return a;
-        }("FAIL", f()));
-    }
-    expect_stdout: "PASS"
-}
-
-issue_2298: {
-    options = {
-        collapse_vars: true,
-        reduce_vars: true,
-        unused: true,
-    }
-    input: {
-        !function() {
-            function f() {
-                var a = undefined;
-                var undefined = a++;
-                try {
-                    !function g(b) {
-                        b[1] = "foo";
-                    }();
-                    console.log("FAIL");
-                } catch (e) {
-                    console.log("PASS");
-                }
-            }
-            f();
-        }();
-    }
-    expect: {
-        !function() {
-            (function() {
-                var a = undefined;
-                var undefined = a++;
-                try {
-                    !function(b) {
-                        (void 0)[1] = "foo";
-                    }();
-                    console.log("FAIL");
-                } catch (e) {
-                    console.log("PASS");
-                }
-            })();
-        }();
-    }
-    expect_stdout: "PASS"
-}
-
-issue_2313_1: {
-    options = {
-        collapse_vars: true,
-        conditionals: true,
-    }
-    input: {
-        var a = 0, b = 0;
-        var foo = {
-            get c() {
-                a++;
-                return 42;
-            },
-            set c(c) {
-                b++;
-            },
-            d: function() {
-                this.c++;
-                if (this.c) console.log(a, b);
-            }
         }
-        foo.d();
+        console.log(f());
     }
     expect: {
-        var a = 0, b = 0;
-        var foo = {
-            get c() {
-                a++;
-                return 42;
-            },
-            set c(c) {
-                b++;
-            },
-            d: function() {
-                this.c++;
-                this.c && console.log(a, b);
-            }
+        function f() {
+            const a = 1;
+            a = 2;
+            return a;
         }
-        foo.d();
+        console.log(f());
     }
-    expect_stdout: "2 1"
+    expect_stdout: true
 }
 
-issue_2313_2: {
+reassign_const_2: {
     options = {
         collapse_vars: true,
     }
     input: {
-        var c = 0;
-        !function a() {
-            a && c++;
-            var a = 0;
-            a && c++;
-        }();
-        console.log(c);
+        function f() {
+            const a = 1;
+            ++a;
+            return a;
+        }
+        console.log(f());
     }
     expect: {
-        var c = 0;
-        !function a() {
-            a && c++;
-            var a = 0;
-            a && c++;
-        }();
-        console.log(c);
-    }
-    expect_stdout: "0"
-}
-
-issue_2319_1: {
-    options = {
-        collapse_vars: true,
-        unused: true,
-    }
-    input: {
-        console.log(function(a) {
+        function f() {
+            const a = 1;
+            ++a;
             return a;
-        }(!function() {
-            return this;
-        }()));
+        }
+        console.log(f());
     }
-    expect: {
-        console.log(function(a) {
-            return !function() {
-                return this;
-            }();
-        }());
-    }
-    expect_stdout: "false"
-}
-
-issue_2319_2: {
-    options = {
-        collapse_vars: true,
-        unused: true,
-    }
-    input: {
-        console.log(function(a) {
-            "use strict";
-            return a;
-        }(!function() {
-            return this;
-        }()));
-    }
-    expect: {
-        console.log(function(a) {
-            "use strict";
-            return a;
-        }(!function() {
-            return this;
-        }()));
-    }
-    expect_stdout: "false"
-}
-
-issue_2319_3: {
-    options = {
-        collapse_vars: true,
-        unused: true,
-    }
-    input: {
-        "use strict";
-        console.log(function(a) {
-            return a;
-        }(!function() {
-            return this;
-        }()));
-    }
-    expect: {
-        "use strict";
-        console.log(function(a) {
-            return !function() {
-                return this;
-            }();
-        }());
-    }
-    expect_stdout: "true"
+    expect_stdout: true
 }

test/compress/concat-strings.js

@@ -21,7 +21,7 @@ concat_1: {
         var c = 1 + x() + 2 + "boo";
         var d = 1 + x() + 2 + 3 + "boo";
         var e = 1 + x() + 2 + "X3boo";
-        var f = "\x00360\x008\0";
+        var f = "\x00360\08\0";
     }
 }
 

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: {
@@ -230,186 +294,3 @@ accessor: {
     }
     expect: {}
 }
-
-issue_2233_1: {
-    options = {
-        pure_getters: "strict",
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        Array.isArray;
-        Boolean;
-        console.log;
-        Date;
-        decodeURI;
-        decodeURIComponent;
-        encodeURI;
-        encodeURIComponent;
-        Error.name;
-        escape;
-        eval;
-        EvalError;
-        Function.length;
-        isFinite;
-        isNaN;
-        JSON;
-        Math.random;
-        Number.isNaN;
-        parseFloat;
-        parseInt;
-        RegExp;
-        Object.defineProperty;
-        String.fromCharCode;
-        RangeError;
-        ReferenceError;
-        SyntaxError;
-        TypeError;
-        unescape;
-        URIError;
-    }
-    expect: {}
-    expect_stdout: true
-}
-
-global_timeout_and_interval_symbols: {
-    options = {
-        pure_getters: "strict",
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        // These global symbols do not exist in the test sandbox
-        // and must be tested separately.
-        clearInterval;
-        clearTimeout;
-        setInterval;
-        setTimeout;
-    }
-    expect: {}
-}
-
-issue_2233_2: {
-    options = {
-        pure_getters: "strict",
-        reduce_vars: true,
-        side_effects: true,
-        unsafe: true,
-        unused: true,
-    }
-    input: {
-        var RegExp;
-        Array.isArray;
-        RegExp;
-        UndeclaredGlobal;
-        function foo() {
-            var Number;
-            AnotherUndeclaredGlobal;
-            Math.sin;
-            Number.isNaN;
-        }
-    }
-    expect: {
-        var RegExp;
-        UndeclaredGlobal;
-        function foo() {
-            var Number;
-            AnotherUndeclaredGlobal;
-            Number.isNaN;
-        }
-    }
-}
-
-issue_2233_3: {
-    options = {
-        pure_getters: "strict",
-        reduce_vars: true,
-        side_effects: true,
-        toplevel: true,
-        unsafe: true,
-        unused: true,
-    }
-    input: {
-        var RegExp;
-        Array.isArray;
-        RegExp;
-        UndeclaredGlobal;
-        function foo() {
-            var Number;
-            AnotherUndeclaredGlobal;
-            Math.sin;
-            Number.isNaN;
-        }
-    }
-    expect: {
-        UndeclaredGlobal;
-    }
-}
-
-global_fns: {
-    options = {
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        Boolean(1, 2);
-        decodeURI(1, 2);
-        decodeURIComponent(1, 2);
-        Date(1, 2);
-        encodeURI(1, 2);
-        encodeURIComponent(1, 2);
-        Error(1, 2);
-        escape(1, 2);
-        EvalError(1, 2);
-        isFinite(1, 2);
-        isNaN(1, 2);
-        Number(1, 2);
-        Object(1, 2);
-        parseFloat(1, 2);
-        parseInt(1, 2);
-        RangeError(1, 2);
-        ReferenceError(1, 2);
-        String(1, 2);
-        SyntaxError(1, 2);
-        TypeError(1, 2);
-        unescape(1, 2);
-        URIError(1, 2);
-        try {
-            Function(1, 2);
-        } catch (e) {
-            console.log(e.name);
-        }
-        try {
-            RegExp(1, 2);
-        } catch (e) {
-            console.log(e.name);
-        }
-        try {
-            Array(NaN);
-        } catch (e) {
-            console.log(e.name);
-        }
-    }
-    expect: {
-        try {
-            Function(1, 2);
-        } catch (e) {
-            console.log(e.name);
-        }
-        try {
-            RegExp(1, 2);
-        } catch (e) {
-            console.log(e.name);
-        }
-        try {
-            Array(NaN);
-        } catch (e) {
-            console.log(e.name);
-        }
-    }
-    expect_stdout: [
-        "SyntaxError",
-        "SyntaxError",
-        "RangeError",
-    ]
-}

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;
@@ -1090,7 +1210,6 @@ var_catch_toplevel: {
             a--;
             try {
                 a++;
-                x();
             } catch(a) {
                 if (a) var a;
                 var a = 10;
@@ -1100,8 +1219,9 @@ var_catch_toplevel: {
     }
     expect: {
         !function() {
+            a--;
             try {
-                x();
+                a++;
             } catch(a) {
                 var a;
             }
@@ -1109,97 +1229,7 @@ var_catch_toplevel: {
     }
 }
 
-issue_2105: {
-    options = {
-        collapse_vars: true,
-        inline: true,
-        passes: 3,
-        reduce_vars: true,
-        side_effects: true,
-        unused: true,
-    }
-    input: {
-        !function(factory) {
-            factory();
-        }( function() {
-            return function(fn) {
-                fn()().prop();
-            }( function() {
-                function bar() {
-                    var quux = function() {
-                        console.log("PASS");
-                    }, foo = function() {
-                        console.log;
-                        quux();
-                    };
-                    return { prop: foo };
-                }
-                return bar;
-            } );
-        });
-    }
-    expect: {
-        (function() {
-            var quux = function() {
-                console.log("PASS");
-            };
-            return {
-                prop: function() {
-                    console.log;
-                    quux();
-                }
-            };
-        })().prop();
-    }
-    expect_stdout: "PASS"
-}
-
-issue_2226_1: {
-    options = {
-        side_effects: true,
-        unused: true,
-    }
-    input: {
-        function f1() {
-            var a = b;
-            a += c;
-        }
-        function f2(a) {
-            a <<= b;
-        }
-        function f3(a) {
-            --a;
-        }
-        function f4() {
-            var a = b;
-            return a *= c;
-        }
-        function f5(a) {
-            x(a /= b);
-        }
-    }
-    expect: {
-        function f1() {
-            b;
-            c;
-        }
-        function f2(a) {
-            b;
-        }
-        function f3(a) {
-            0;
-        }
-        function f4() {
-            var a = b;
-            return a *= c;
-        }
-        function f5(a) {
-            x(a /= b);
-        }
-    }
-}
-
-issue_2226_2: {
+reassign_const: {
     options = {
         cascade: true,
         sequences: true,
@@ -1207,57 +1237,19 @@ issue_2226_2: {
         unused: true,
     }
     input: {
-        console.log(function(a, b) {
-            a += b;
+        function f() {
+            const a = 1;
+            a = 2;
             return a;
-        }(1, 2));
-    }
-    expect: {
-        console.log(function(a, b) {
-            return a += b;
-        }(1, 2));
-    }
-    expect_stdout: "3"
-}
-
-issue_2226_3: {
-    options = {
-        collapse_vars: true,
-        side_effects: true,
-        unused: true,
-    }
-    input: {
-        console.log(function(a, b) {
-            a += b;
-            return a;
-        }(1, 2));
-    }
-    expect: {
-        console.log(function(a, b) {
-            return a += 2;
-        }(1));
-    }
-    expect_stdout: "3"
-}
-
-issue_2288: {
-    options = {
-        unused: true,
-    }
-    beautify = {
-        beautify: true,
-    }
-    input: {
-        function foo(o) {
-            for (var j = o.a, i = 0; i < 0; i++);
-            for (var i = 0; i < 0; i++);
         }
+        console.log(f());
     }
     expect: {
-        function foo(o) {
-            o.a;
-            for (i = 0; i < 0; i++);
-            for (var i = 0; i < 0; i++);
+        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,
@@ -250,26 +344,22 @@ unsafe_constant: {
 
 unsafe_object: {
     options = {
-        evaluate: true,
-        reduce_vars: true,
-        toplevel: true,
-        unsafe: true,
+        evaluate  : true,
+        unsafe    : true
     }
     input: {
-        var o = { a: 1 };
         console.log(
-            o + 1,
-            o.a + 1,
-            o.b + 1,
-            o.a.b + 1
+            ({a:1}) + 1,
+            ({a:1}).a + 1,
+            ({a:1}).b + 1,
+            ({a:1}).a.b + 1
         );
     }
     expect: {
-        var o = { a: 1 };
         console.log(
-            o + 1,
+            ({a:1}) + 1,
             2,
-            o.b + 1,
+            ({a:1}).b + 1,
             1..b + 1
         );
     }
@@ -278,26 +368,22 @@ unsafe_object: {
 
 unsafe_object_nested: {
     options = {
-        evaluate: true,
-        reduce_vars: true,
-        toplevel: true,
-        unsafe: true,
+        evaluate  : true,
+        unsafe    : true
     }
     input: {
-        var o = { a: { b: 1 } };
         console.log(
-            o + 1,
-            o.a + 1,
-            o.b + 1,
-            o.a.b + 1
+            ({a:{b:1}}) + 1,
+            ({a:{b:1}}).a + 1,
+            ({a:{b:1}}).b + 1,
+            ({a:{b:1}}).a.b + 1
         );
     }
     expect: {
-        var o = { a: { b: 1 } };
         console.log(
-            o + 1,
-            o.a + 1,
-            o.b + 1,
+            ({a:{b:1}}) + 1,
+            ({a:{b:1}}).a + 1,
+            ({a:{b:1}}).b + 1,
             2
         );
     }
@@ -306,25 +392,21 @@ unsafe_object_nested: {
 
 unsafe_object_complex: {
     options = {
-        evaluate: true,
-        reduce_vars: true,
-        toplevel: true,
-        unsafe: true,
+        evaluate  : true,
+        unsafe    : true
     }
     input: {
-        var o = { a: { b: 1 }, b: 1 };
         console.log(
-            o + 1,
-            o.a + 1,
-            o.b + 1,
-            o.a.b + 1
+            ({a:{b:1},b:1}) + 1,
+            ({a:{b:1},b:1}).a + 1,
+            ({a:{b:1},b:1}).b + 1,
+            ({a:{b:1},b:1}).a.b + 1
         );
     }
     expect: {
-        var o = { a: { b: 1 }, b: 1 };
         console.log(
-            o + 1,
-            o.a + 1,
+            ({a:{b:1},b:1}) + 1,
+            ({a:{b:1},b:1}).a + 1,
             2,
             2
         );
@@ -334,26 +416,22 @@ unsafe_object_complex: {
 
 unsafe_object_repeated: {
     options = {
-        evaluate: true,
-        reduce_vars: true,
-        toplevel: true,
-        unsafe: true,
+        evaluate  : true,
+        unsafe    : true
     }
     input: {
-        var o = { a: { b: 1 }, a: 1 };
         console.log(
-            o + 1,
-            o.a + 1,
-            o.b + 1,
-            o.a.b + 1
+            ({a:{b:1},a:1}) + 1,
+            ({a:{b:1},a:1}).a + 1,
+            ({a:{b:1},a:1}).b + 1,
+            ({a:{b:1},a:1}).a.b + 1
         );
     }
     expect: {
-        var o = { a: { b: 1 }, a: 1 };
         console.log(
-            o + 1,
+            ({a:{b:1},a:1}) + 1,
             2,
-            o.b + 1,
+            ({a:{b:1},a:1}).b + 1,
             1..b + 1
         );
     }
@@ -402,9 +480,9 @@ unsafe_function: {
     expect: {
         console.log(
             ({a:{b:1},b:function(){}}) + 1,
-            ({b:function(){}}, {b:1}) + 1,
-            ({a:{b:1}}, function(){}) + 1,
-            ({b:function(){}}, {b:1}).b + 1
+            ({a:{b:1},b:function(){}}).a + 1,
+            ({a:{b:1},b:function(){}}).b + 1,
+            ({a:{b:1},b:function(){}}).a.b + 1
         );
     }
     expect_stdout: true
@@ -652,27 +730,25 @@ unsafe_prototype_function: {
         var d = ({toString: 0}) + "";
         var e = (({valueOf: 0}) + "")[2];
         var f = (({toString: 0}) + "")[2];
-        var g = ({}, 0)();
-        var h = ({}, 0)();
+        var g = ({valueOf: 0}).valueOf();
+        var h = "" + ({toString: 0});
     }
 }
 
 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);
     }
@@ -682,20 +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);
     }
@@ -798,15 +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)
         );
     }
 }
@@ -1010,178 +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"
-}
-
-issue_2207_1: {
-    options = {
-        evaluate: true,
-        unsafe: true,
-    }
-    input: {
-        console.log(String.fromCharCode(65));
-        console.log(Math.max(3, 6, 2, 7, 3, 4));
-        console.log(Math.cos(1.2345));
-        console.log(Math.cos(1.2345) - Math.sin(4.321));
-        console.log(Math.pow(Math.PI, Math.E - Math.LN10));
-    }
-    expect: {
-        console.log("A");
-        console.log(7);
-        console.log(Math.cos(1.2345));
-        console.log(1.2543732512566947);
-        console.log(1.6093984514472044);
-    }
-    expect_stdout: true
-}
-
-issue_2207_2: {
-    options = {
-        evaluate: true,
-        unsafe: true,
-    }
-    input: {
-        console.log(Math.E);
-        console.log(Math.LN10);
-        console.log(Math.LN2);
-        console.log(Math.LOG2E);
-        console.log(Math.LOG10E);
-        console.log(Math.PI);
-        console.log(Math.SQRT1_2);
-        console.log(Math.SQRT2);
-    }
-    expect: {
-        console.log(Math.E);
-        console.log(Math.LN10);
-        console.log(Math.LN2);
-        console.log(Math.LOG2E);
-        console.log(Math.LOG10E);
-        console.log(Math.PI);
-        console.log(Math.SQRT1_2);
-        console.log(Math.SQRT2);
-    }
-    expect_stdout: true
-}
-
-issue_2207_3: {
-    options = {
-        evaluate: true,
-        unsafe: true,
-    }
-    input: {
-        console.log(Number.MAX_VALUE);
-        console.log(Number.MIN_VALUE);
-        console.log(Number.NaN);
-        console.log(Number.NEGATIVE_INFINITY);
-        console.log(Number.POSITIVE_INFINITY);
-    }
-    expect: {
-        console.log(Number.MAX_VALUE);
-        console.log(5e-324);
-        console.log(NaN);
-        console.log(-1/0);
-        console.log(1/0);
-    }
-    expect_stdout: true
-}
-
-issue_2231_1: {
-    options = {
-        evaluate: true,
-        unsafe: true,
-    }
-    input: {
-        console.log(Object.keys(void 0));
-    }
-    expect: {
-        console.log(Object.keys(void 0));
-    }
-    expect_stdout: true
-}
-
-issue_2231_2: {
-    options = {
-        evaluate: true,
-        unsafe: true,
-    }
-    input: {
-        console.log(Object.getOwnPropertyNames(null));
-    }
-    expect: {
-        console.log(Object.getOwnPropertyNames(null));
-    }
-    expect_stdout: true
-}

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() {
@@ -171,340 +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("n,o", "o.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"
-}
-
-issue_2107: {
-    options = {
-        cascade: true,
-        collapse_vars: true,
-        inline: true,
-        sequences: true,
-        side_effects: true,
-        unused: true,
-    }
-    input: {
-        var c = 0;
-        !function() {
-            c++;
-        }(c++ + new function() {
-            this.a = 0;
-            var a = (c = c + 1) + (c = 1 + c);
-            return c++ + a;
-        }());
-        console.log(c);
-    }
-    expect: {
-        var c = 0;
-        c++, new function() {
-            this.a = 0, c = 1 + (c += 1), c++;
-        }(), c++, console.log(c);
-    }
-    expect_stdout: "5"
-}
-
-issue_2114_1: {
-    options = {
-        collapse_vars: true,
-        if_return: true,
-        inline: true,
-        keep_fargs: false,
-        side_effects: true,
-        unused: true,
-    }
-    input: {
-        var c = 0;
-        !function(a) {
-            a = 0;
-        }([ {
-            0: c = c + 1,
-            length: c = 1 + c
-        }, typeof void function a() {
-            var b = function f1(a) {
-            }(b && (b.b += (c = c + 1, 0)));
-        }() ]);
-        console.log(c);
-    }
-    expect: {
-        var c = 0;
-        c = 1 + (c += 1), function() {
-            var b = void (b && (b.b += (c += 1, 0)));
-        }();
-        console.log(c);
-    }
-    expect_stdout: "2"
-}
-
-issue_2114_2: {
-    options = {
-        collapse_vars: true,
-        if_return: true,
-        inline: true,
-        keep_fargs: false,
-        passes: 2,
-        side_effects: true,
-        unused: true,
-    }
-    input: {
-        var c = 0;
-        !function(a) {
-            a = 0;
-        }([ {
-            0: c = c + 1,
-            length: c = 1 + c
-        }, typeof void function a() {
-            var b = function f1(a) {
-            }(b && (b.b += (c = c + 1, 0)));
-        }() ]);
-        console.log(c);
-    }
-    expect: {
-        var c = 0;
-        c = 1 + (c += 1), function() {
-            var b = void (b && (b.b += (c += 1, 0)));
-        }();
-        console.log(c);
-    }
-    expect_stdout: "2"
-}

test/compress/global_defs.js

@@ -37,7 +37,6 @@ object: {
                 VALUE: 42,
             },
         },
-        side_effects: true,
         unsafe: true,
     }
     input: {
@@ -121,7 +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);
@@ -131,7 +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);
@@ -141,9 +140,9 @@ mixed: {
         console.log(CONFIG);
     }
     expect_warnings: [
+        'WARN: global_defs CONFIG.VALUE redefined [test/compress/global_defs.js:126,22]',
         'WARN: global_defs CONFIG.VALUE redefined [test/compress/global_defs.js:127,22]',
-        'WARN: global_defs CONFIG.VALUE redefined [test/compress/global_defs.js:128,22]',
-        'WARN: global_defs CONFIG.VALUE redefined [test/compress/global_defs.js:130,8]',
+        'WARN: global_defs CONFIG.VALUE redefined [test/compress/global_defs.js:129,8]',
     ]
 }
 
@@ -161,38 +160,3 @@ issue_1801: {
         console.log(!0);
     }
 }
-
-issue_1986: {
-    options = {
-        global_defs: {
-            "@alert": "console.log",
-        },
-    }
-    input: {
-        alert(42);
-    }
-    expect: {
-        console.log(42);
-    }
-}
-
-issue_2167: {
-    options = {
-        conditionals: true,
-        dead_code: true,
-        evaluate: true,
-        global_defs: {
-            "@isDevMode": "function(){}",
-        },
-        side_effects: true,
-    }
-    input: {
-        if (isDevMode()) {
-            greetOverlord();
-        }
-        doWork();
-    }
-    expect: {
-        doWork();
-    }
-}

test/compress/harmony.js

@@ -0,0 +1,585 @@
+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: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        export default 1 + 2;
+        export var foo = 4;
+        export let foo = 6;
+        export const foo = 6;
+        export function foo() {};
+        export class foo { };
+    }
+    expect_exact: "export default 3;export var foo=4;export let foo=6;export const foo=6;export function foo(){};export class foo{};"
+}
+
+export_default_object_expression: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        export default {
+            foo: 1 + 2,
+            bar() { return 4; },
+            get baz() { return this.foo; },
+        };
+    }
+    expect_exact: "export default{foo:3,bar(){return 4},get baz(){return this.foo}};"
+}
+
+export_default_array: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        export default [ 1 + 2, foo ];
+    }
+    expect_exact: "export default[3,foo];"
+}
+
+export_default_anon_function: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        export default function(){
+            console.log(1 + 2);
+        }
+    }
+    expect_exact: "export default function(){console.log(3)};"
+}
+
+export_default_anon_class: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        export default class {
+            foo() { console.log(1 + 2); }
+        }
+    }
+    expect_exact: "export default class{foo(){console.log(3)}};"
+}
+
+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: []
+                    });
+            }
+        }
+    }
+}
+
+class_extends: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        function f() {
+            class foo extends bar {}
+            class pro extends some.prop {}
+            class arr extends stuff[1 - 1] {}
+            class bin extends (a || b) {}
+            class seq extends (a, b) {}
+            class ter extends (a ? b : c) {}
+            class uni extends (!0) {}
+        }
+    }
+    expect_exact: "function f(){class foo extends bar{}class pro extends some.prop{}class arr extends stuff[0]{}class bin extends(a||b){}class seq extends(a,b){}class ter extends(a?b:c){}class uni extends(!0){}}"
+}
+
+class_extends_class: {
+    options = {
+    }
+    input: {
+        class anon extends class {} {}
+        class named extends class base {} {}
+    }
+    expect_exact: "class anon extends class{}{}class named extends class base{}{}"
+}
+
+class_extends_function: {
+    options = {
+    }
+    input: {
+        class anon extends function(){} {}
+        class named extends function base(){} {}
+    }
+    expect_exact: "class anon extends function(){}{}class named extends function base(){}{}"
+}
+
+class_extends_regex: {
+    options = {
+    }
+    input: {
+        function f() {
+            class rx1 extends (/rx/) {}
+            // class rx2 extends /rx/ {}  // FIXME - parse error
+        }
+    }
+    expect_exact: "function f(){class rx1 extends(/rx/){}}"
+}

test/compress/hoist.js

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

test/compress/hoist_vars.js

@@ -88,24 +88,3 @@ sequences_funs: {
         }
     }
 }
-
-issue_2295: {
-    options = {
-        collapse_vars: true,
-        hoist_vars: true,
-    }
-    input: {
-        function foo(o) {
-            var a = o.a;
-            if (a) return a;
-            var a = 1;
-        }
-    }
-    expect: {
-        function foo(o) {
-            var a = o.a;
-            if (a) return a;
-            a = 1;
-        }
-    }
-}

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

@@ -71,13 +71,11 @@ non_hoisted_function_after_return_2a: {
         "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:51,16]",
         "WARN: Dropping unused variable a [test/compress/issue-1034.js:48,20]",
         "WARN: Dropping unused function nope [test/compress/issue-1034.js:55,21]",
-        "WARN: pass 0: last_count: Infinity, count: 37",
         "WARN: Dropping unreachable code [test/compress/issue-1034.js:53,12]",
         "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:53,12]",
         "WARN: Dropping unreachable code [test/compress/issue-1034.js:56,12]",
         "WARN: Dropping unused variable b [test/compress/issue-1034.js:51,20]",
         "WARN: Dropping unused variable c [test/compress/issue-1034.js:53,16]",
-        "WARN: pass 1: last_count: 37, count: 18",
     ]
 }
 
@@ -111,146 +109,10 @@ non_hoisted_function_after_return_2b: {
     }
     expect_warnings: [
         // duplicate warnings no longer emitted
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:97,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:97,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:99,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:99,12]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:103,12]",
-    ]
-}
-
-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:133,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:136,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:139,12]",
-        "WARN: Dropping unused function UnusedFunction [test/compress/issue-1034.js:140,21]",
-    ]
-}
-
-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:175,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:175,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:178,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:178,16]",
-        "WARN: Dropping unused variable a [test/compress/issue-1034.js:175,20]",
-        "WARN: Dropping unused function nope [test/compress/issue-1034.js:182,21]",
-        "WARN: pass 0: last_count: Infinity, count: 48",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:180,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:180,12]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:183,12]",
-        "WARN: Dropping unused variable b [test/compress/issue-1034.js:178,20]",
-        "WARN: Dropping unused variable c [test/compress/issue-1034.js:180,16]",
-        "WARN: pass 1: last_count: 48, count: 29",
-    ]
-}
-
-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:229,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:229,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:231,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:231,12]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:235,12]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:95,16]",
+        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:95,16]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:97,12]",
+        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:97,12]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:101,12]",
     ]
 }

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-1261.js

@@ -96,13 +96,6 @@ pure_function_calls_toplevel: {
             })();
         })();
 
-        // pure top-level calls will be dropped regardless of the leading comments position
-        var MyClass = /*#__PURE__*//*@class*/(function(){
-            function MyClass() {}
-            MyClass.prototype.method = function() {};
-            return MyClass;
-        })();
-
         // comment #__PURE__ comment
         bar(), baz(), quux();
         a.b(), /* @__PURE__ */ c.d.e(), f.g();
@@ -117,12 +110,10 @@ pure_function_calls_toplevel: {
         "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:92,37]",
         "WARN: Dropping unused variable iife2 [test/compress/issue-1261.js:92,16]",
         "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:90,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:107,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:108,31]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:100,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:101,31]",
         "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:84,33]",
         "WARN: Dropping unused variable iife1 [test/compress/issue-1261.js:84,12]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:100,45]",
-        "WARN: Dropping unused variable MyClass [test/compress/issue-1261.js:100,12]",
     ]
 }
 
@@ -157,29 +148,29 @@ should_warn: {
         baz();
     }
     expect_warnings: [
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:137,61]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:137,23]",
-        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:137,23]",
-        "WARN: Boolean || always true [test/compress/issue-1261.js:138,23]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:138,23]",
-        "WARN: Condition always true [test/compress/issue-1261.js:138,23]",
-        "WARN: Condition left of || always true [test/compress/issue-1261.js:139,8]",
-        "WARN: Condition always true [test/compress/issue-1261.js:139,8]",
-        "WARN: Boolean && always false [test/compress/issue-1261.js:140,23]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:140,23]",
-        "WARN: Condition always false [test/compress/issue-1261.js:140,23]",
-        "WARN: Condition left of && always false [test/compress/issue-1261.js:141,8]",
-        "WARN: Condition always false [test/compress/issue-1261.js:141,8]",
-        "WARN: + in boolean context always true [test/compress/issue-1261.js:142,23]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:142,23]",
-        "WARN: Condition always true [test/compress/issue-1261.js:142,23]",
-        "WARN: + in boolean context always true [test/compress/issue-1261.js:143,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:143,31]",
-        "WARN: Condition always true [test/compress/issue-1261.js:143,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:144,23]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:145,24]",
-        "WARN: Condition always true [test/compress/issue-1261.js:145,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:146,31]",
-        "WARN: Condition always false [test/compress/issue-1261.js:146,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:128,61]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:128,23]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:128,23]",
+        "WARN: Boolean || always true [test/compress/issue-1261.js:129,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:129,23]",
+        "WARN: Condition always true [test/compress/issue-1261.js:129,23]",
+        "WARN: Condition left of || always true [test/compress/issue-1261.js:130,8]",
+        "WARN: Condition always true [test/compress/issue-1261.js:130,8]",
+        "WARN: Boolean && always false [test/compress/issue-1261.js:131,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:131,23]",
+        "WARN: Condition always false [test/compress/issue-1261.js:131,23]",
+        "WARN: Condition left of && always false [test/compress/issue-1261.js:132,8]",
+        "WARN: Condition always false [test/compress/issue-1261.js:132,8]",
+        "WARN: + in boolean context always true [test/compress/issue-1261.js:133,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:133,23]",
+        "WARN: Condition always true [test/compress/issue-1261.js:133,23]",
+        "WARN: + in boolean context always true [test/compress/issue-1261.js:134,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:134,31]",
+        "WARN: Condition always true [test/compress/issue-1261.js:134,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:135,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:136,24]",
+        "WARN: Condition always true [test/compress/issue-1261.js:136,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:137,31]",
+        "WARN: Condition always false [test/compress/issue-1261.js:137,8]",
     ]
 }

test/compress/issue-1321.js

@@ -1,8 +1,6 @@
 issue_1321_no_debug: {
-    mangle = {
-        properties: {
-            keep_quoted: true,
-        },
+    mangle_props = {
+        keep_quoted: true
     }
     input: {
         var x = {};
@@ -12,19 +10,17 @@ issue_1321_no_debug: {
     }
     expect: {
         var x = {};
-        x.x = 1;
-        x["a"] = 2 * x.x;
-        console.log(x.x, x["a"]);
+        x.b = 1;
+        x["a"] = 2 * x.b;
+        console.log(x.b, x["a"]);
     }
     expect_stdout: true
 }
 
 issue_1321_debug: {
-    mangle = {
-        properties: {
-            debug: "",
-            keep_quoted: true,
-        },
+    mangle_props = {
+        keep_quoted: true,
+        debug: ""
     }
     input: {
         var x = {};
@@ -34,18 +30,16 @@ issue_1321_debug: {
     }
     expect: {
         var x = {};
-        x.x = 1;
-        x["_$foo$_"] = 2 * x.x;
-        console.log(x.x, x["_$foo$_"]);
+        x.a = 1;
+        x["_$foo$_"] = 2 * x.a;
+        console.log(x.a, x["_$foo$_"]);
     }
     expect_stdout: true
 }
 
 issue_1321_with_quoted: {
-    mangle = {
-        properties: {
-            keep_quoted: false,
-        },
+    mangle_props = {
+        keep_quoted: false
     }
     input: {
         var x = {};
@@ -55,9 +49,9 @@ issue_1321_with_quoted: {
     }
     expect: {
         var x = {};
-        x.x = 1;
-        x["o"] = 2 * x.x;
-        console.log(x.x, x["o"]);
+        x.a = 1;
+        x["b"] = 2 * x.a;
+        console.log(x.a, x["b"]);
     }
     expect_stdout: true
 }

test/compress/issue-1446.js

@@ -1,7 +1,6 @@
 typeof_eq_undefined: {
     options = {
-        comparisons: true,
-        typeofs: true,
+        comparisons: true
     }
     input: {
         var a = typeof b != "undefined";
@@ -25,7 +24,6 @@ typeof_eq_undefined_ie8: {
     options = {
         comparisons: true,
         ie8: true,
-        typeofs: true,
     }
     input: {
         var a = typeof b != "undefined";
@@ -47,8 +45,7 @@ typeof_eq_undefined_ie8: {
 
 undefined_redefined: {
     options = {
-        comparisons: true,
-        typeofs: true,
+        comparisons: true
     }
     input: {
         function f(undefined) {
@@ -61,8 +58,7 @@ undefined_redefined: {
 
 undefined_redefined_mangle: {
     options = {
-        comparisons: true,
-        typeofs: true,
+        comparisons: true
     }
     mangle = {}
     input: {

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

@@ -1,7 +1,5 @@
 mangle_props: {
-    mangle = {
-        properties: true,
-    }
+    mangle_props = {}
     input: {
         var obj = {
             undefined: 1,
@@ -56,12 +54,10 @@ mangle_props: {
 }
 
 numeric_literal: {
-    mangle = {
-        properties: true,
-    }
     beautify = {
         beautify: true,
     }
+    mangle_props = {}
     input: {
         var obj = {
             0: 0,
@@ -86,7 +82,7 @@ numeric_literal: {
         '    42: 2,',
         '    "42": 3,',
         '    37: 4,',
-        '    o: 5,',
+        '    a: 5,',
         '    1e42: 6,',
         '    b: 7,',
         '    "1e+42": 8',
@@ -96,7 +92,7 @@ numeric_literal: {
         '',
         'console.log(obj[42], obj["42"]);',
         '',
-        'console.log(obj[37], obj["o"], obj[37], obj["37"]);',
+        'console.log(obj[37], obj["a"], obj[37], obj["37"]);',
         '',
         'console.log(obj[1e42], obj["b"], obj["1e+42"]);',
     ]
@@ -107,139 +103,3 @@ numeric_literal: {
         "8 7 8",
     ]
 }
-
-identifier: {
-    mangle = {
-        properties: true,
-    }
-    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 = {
-            e: 1,
-            t: 2,
-            n: 3,
-            a: 4,
-            i: 5,
-            o: 6,
-            r: 7,
-            l: 8,
-            s: 9,
-            c: 10,
-            f: 11,
-            u: 12,
-            d: 13,
-            h: 14,
-            p: 15,
-            b: 16,
-            v: 17,
-            w: 18,
-            y: 19,
-            g: 20,
-            m: 21,
-            k: 22,
-            x: 23,
-            j: 24,
-            z: 25,
-            q: 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,
-            ee: 57,
-            te: 58,
-            ne: 59,
-            ae: 60,
-            ie: 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-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

@@ -1,493 +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_1: {
-    options = {
-        inline: true,
-        side_effects: true,
-    }
-    input: {
-        /*@__PURE__*/(function() {
-            console.log("hello");
-        }());
-    }
-    expect_exact: ""
-}
-
-pure_annotation_2: {
-    options = {
-        collapse_vars: true,
-        inline: true,
-        side_effects: true,
-    }
-    input: {
-        /*@__PURE__*/(function(n) {
-            console.log("hello", n);
-        }(42));
-    }
-    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;
-        ++a && a.var, a++;
-        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;
-        ++a && a.var, a++;
-        console.log(a);
-    }
-    expect_stdout: "3"
-}

test/compress/issue-747.js

@@ -1,45 +1,37 @@
 dont_reuse_prop: {
-    mangle = {
-        properties: {
-            regex: /asd/,
-        },
-    }
+    mangle_props = {
+        regex: /asd/
+    };
+
     input: {
-        "aaaaaaaaaabbbbb";
         var obj = {};
         obj.a = 123;
         obj.asd = 256;
         console.log(obj.a);
     }
     expect: {
-        "aaaaaaaaaabbbbb";
         var obj = {};
         obj.a = 123;
         obj.b = 256;
         console.log(obj.a);
     }
-    expect_stdout: "123"
 }
 
 unmangleable_props_should_always_be_reserved: {
-    mangle = {
-        properties: {
-            regex: /asd/,
-        },
-    }
+    mangle_props = {
+        regex: /asd/
+    };
+
     input: {
-        "aaaaaaaaaabbbbb";
         var obj = {};
         obj.asd = 256;
         obj.a = 123;
         console.log(obj.a);
     }
     expect: {
-        "aaaaaaaaaabbbbb";
         var obj = {};
         obj.b = 256;
         obj.a = 123;
         console.log(obj.a);
     }
-    expect_stdout: "123"
-}
+}

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,
@@ -436,17 +480,3 @@ do_switch: {
         } while (false);
     }
 }
-
-in_parenthesis_1: {
-    input: {
-        for (("foo" in {});0;);
-    }
-    expect_exact: 'for(("foo"in{});0;);'
-}
-
-in_parenthesis_2: {
-    input: {
-        for ((function(){ "foo" in {}; });0;);
-    }
-    expect_exact: 'for(function(){"foo"in{}};0;);'
-}

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

@@ -83,18 +83,18 @@ new_with_unary_prefix: {
     expect_exact: 'var bar=(+new Date).toString(32);';
 }
 
-dot_parenthesis_1: {
-    input: {
-        console.log(new (Math.random().constructor) instanceof Number);
+new_with_assignement_expression: {
+    options = {
+        evaluate: true
     }
-    expect_exact: "console.log(new(Math.random().constructor)instanceof Number);"
-    expect_stdout: "true"
-}
-
-dot_parenthesis_2: {
     input: {
-        console.log(typeof new function(){Math.random()}.constructor);
+        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]);
     }
-    expect_exact: "console.log(typeof new function(){Math.random()}.constructor);"
-    expect_stdout: "function"
 }

test/compress/node_version.js

@@ -1,4 +1,4 @@
-eval_let_6: {
+eval_let: {
     input: {
         eval("let a;");
         console.log();
@@ -10,29 +10,3 @@ eval_let_6: {
     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

@@ -13,10 +13,8 @@ keep_properties: {
 dot_properties: {
     options = {
         properties: true,
-    }
-    beautify = {
         ie8: true,
-    }
+    };
     input: {
         a["foo"] = "bar";
         a["if"] = "if";
@@ -38,10 +36,8 @@ dot_properties: {
 dot_properties_es5: {
     options = {
         properties: true,
-    }
-    beautify = {
         ie8: false,
-    }
+    };
     input: {
         a["foo"] = "bar";
         a["if"] = "if";
@@ -128,11 +124,9 @@ evaluate_string_length: {
 }
 
 mangle_properties: {
-    mangle = {
-        properties: {
-            keep_quoted: false,
-        },
-    }
+    mangle_props = {
+        keep_quoted: false
+    };
     input: {
         a["foo"] = "bar";
         a.color = "red";
@@ -143,9 +137,9 @@ mangle_properties: {
     expect: {
         a["a"] = "bar";
         a.b = "red";
-        x = {o: 10};
-        a.r(x.o, a.a);
-        a['r']({b: "blue", a: "baz"});
+        x = {c: 10};
+        a.d(x.c, a.a);
+        a['d']({b: "blue", a: "baz"});
     }
 }
 
@@ -153,10 +147,9 @@ mangle_unquoted_properties: {
     options = {
         properties: false
     }
-    mangle = {
-        properties: {
-            keep_quoted: true,
-        },
+    mangle_props = {
+        builtins: true,
+        keep_quoted: true
     }
     beautify = {
         beautify: false,
@@ -185,26 +178,24 @@ mangle_unquoted_properties: {
         function f1() {
             a["foo"] = "bar";
             a.color = "red";
-            a.r = 2;
-            x = {"bar": 10, b: 7};
-            a.b = 9;
+            a.b = 2;
+            x = {"bar": 10, c: 7};
+            a.c = 9;
         }
         function f2() {
             a.foo = "bar";
             a['color'] = "red";
-            x = {bar: 10, b: 7};
-            a.b = 9;
-            a.r = 3;
+            x = {bar: 10, c: 7};
+            a.c = 9;
+            a.b = 3;
         }
     }
 }
 
 mangle_debug: {
-    mangle = {
-        properties: {
-            debug: "",
-        },
-    }
+    mangle_props = {
+        debug: ""
+    };
     input: {
         a.foo = "bar";
         x = { baz: "ban" };
@@ -216,11 +207,9 @@ mangle_debug: {
 }
 
 mangle_debug_true: {
-    mangle = {
-        properties: {
-            debug: true,
-        },
-    }
+    mangle_props = {
+        debug: true
+    };
     input: {
         a.foo = "bar";
         x = { baz: "ban" };
@@ -232,11 +221,9 @@ mangle_debug_true: {
 }
 
 mangle_debug_suffix: {
-    mangle = {
-        properties: {
-            debug: "XYZ",
-        },
-    }
+    mangle_props = {
+        debug: "XYZ"
+    };
     input: {
         a.foo = "bar";
         x = { baz: "ban" };
@@ -251,12 +238,11 @@ mangle_debug_suffix_keep_quoted: {
     options = {
         properties: false
     }
-    mangle = {
-        properties: {
-            debug: "XYZ",
-            keep_quoted: true,
-            reserved: [],
-        },
+    mangle_props = {
+        builtins: true,
+        keep_quoted: true,
+        debug: "XYZ",
+        reserved: []
     }
     beautify = {
         beautify: false,
@@ -571,236 +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"
-}
-
-issue_2208_1: {
-    options = {
-        inline: true,
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        console.log({
-            p: function() {
-                return 42;
-            }
-        }.p());
-    }
-    expect: {
-        console.log(42);
-    }
-    expect_stdout: "42"
-}
-
-issue_2208_2: {
-    options = {
-        inline: true,
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        console.log({
-            a: 42,
-            p: function() {
-                return this.a;
-            }
-        }.p());
-    }
-    expect: {
-        console.log({
-            a: 42,
-            p: function() {
-                return this.a;
-            }
-        }.p());
-    }
-    expect_stdout: "42"
-}
-
-issue_2208_3: {
-    options = {
-        inline: true,
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        a = 42;
-        console.log({
-            p: function() {
-                return function() {
-                    return this.a;
-                }();
-            }
-        }.p());
-    }
-    expect: {
-        a = 42;
-        console.log(function() {
-            return this.a;
-        }());
-    }
-    expect_stdout: "42"
-}
-
-issue_2208_4: {
-    options = {
-        inline: true,
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        function foo() {}
-        console.log({
-            a: foo(),
-            p: function() {
-                return 42;
-            }
-        }.p());
-    }
-    expect: {
-        function foo() {}
-        console.log((foo(), function() {
-            return 42;
-        })());
-    }
-    expect_stdout: "42"
-}
-
-issue_2208_5: {
-    options = {
-        inline: true,
-        side_effects: true,
-        unsafe: true,
-    }
-    input: {
-        console.log({
-            p: "FAIL",
-            p: function() {
-                return 42;
-            }
-        }.p());
-    }
-    expect: {
-        console.log(42);
-    }
-    expect_stdout: "42"
-}
-
-issue_2256: {
-    options = {
-        side_effects: true,
-    }
-    mangle = {
-        properties: {
-            keep_quoted: true,
-        },
-    }
-    input: {
-        ({ "keep": 1 });
-        g.keep = g.change;
-    }
-    expect: {
-        g.keep = g.g;
-    }
-}

test/compress/pure_getters.js

@@ -178,424 +178,3 @@ impure_getter_2: {
     }
     expect: {}
 }
-
-issue_2110_1: {
-    options = {
-        cascade: true,
-        pure_getters: "strict",
-        sequences: true,
-        side_effects: true,
-        reduce_vars: true,
-        unused: true,
-    }
-    input: {
-        function f() {
-            function f() {}
-            function g() {
-                return this;
-            }
-            f.g = g;
-            return f.g();
-        }
-        console.log(typeof f());
-    }
-    expect: {
-        function f() {
-            function f() {}
-            return f.g = function() {
-                return this;
-            }, f.g();
-        }
-        console.log(typeof f());
-    }
-    expect_stdout: "function"
-}
-
-issue_2110_2: {
-    options = {
-        collapse_vars: true,
-        pure_getters: "strict",
-        reduce_vars: true,
-        unused: true,
-    }
-    input: {
-        function f() {
-            function f() {}
-            function g() {
-                return this;
-            }
-            f.g = g;
-            return f.g();
-        }
-        console.log(typeof f());
-    }
-    expect: {
-        function f() {
-            function f() {}
-            f.g = function() {
-                return this;
-            };
-            return f.g();
-        }
-        console.log(typeof f());
-    }
-    expect_stdout: "function"
-}
-
-set_immutable_1: {
-    options = {
-        collapse_vars: true,
-        evaluate: true,
-        pure_getters: "strict",
-        reduce_vars: true,
-        toplevel: true,
-        unused: true,
-    }
-    input: {
-        var a = 1;
-        a.foo += "";
-        if (a.foo) console.log("FAIL");
-        else console.log("PASS");
-    }
-    expect: {
-        1..foo += "";
-        if (1..foo) console.log("FAIL");
-        else console.log("PASS");
-    }
-    expect_stdout: "PASS"
-}
-
-set_immutable_2: {
-    options = {
-        cascade: true,
-        conditionals: true,
-        pure_getters: "strict",
-        reduce_vars: true,
-        sequences: true,
-        side_effects: true,
-        toplevel: true,
-    }
-    input: {
-        var a = 1;
-        a.foo += "";
-        if (a.foo) console.log("FAIL");
-        else console.log("PASS");
-    }
-    expect: {
-        var a = 1;
-        a.foo += "", a.foo ? console.log("FAIL") : console.log("PASS");
-    }
-    expect_stdout: "PASS"
-}
-
-set_immutable_3: {
-    options = {
-        collapse_vars: true,
-        evaluate: true,
-        pure_getters: "strict",
-        reduce_vars: true,
-        toplevel: true,
-        unused: true,
-    }
-    input: {
-        "use strict";
-        var a = 1;
-        a.foo += "";
-        if (a.foo) console.log("FAIL");
-        else console.log("PASS");
-    }
-    expect: {
-        "use strict";
-        1..foo += "";
-        if (1..foo) console.log("FAIL");
-        else console.log("PASS");
-    }
-    expect_stdout: true
-}
-
-set_immutable_4: {
-    options = {
-        cascade: true,
-        conditionals: true,
-        pure_getters: "strict",
-        reduce_vars: true,
-        sequences: true,
-        side_effects: true,
-        toplevel: true,
-    }
-    input: {
-        "use strict";
-        var a = 1;
-        a.foo += "";
-        if (a.foo) console.log("FAIL");
-        else console.log("PASS");
-    }
-    expect: {
-        "use strict";
-        var a = 1;
-        a.foo += "", a.foo ? console.log("FAIL") : console.log("PASS");
-    }
-    expect_stdout: true
-}
-
-set_mutable_1: {
-    options = {
-        collapse_vars: true,
-        evaluate: true,
-        pure_getters: "strict",
-        reduce_vars: true,
-        unused: true,
-    }
-    input: {
-        !function a() {
-            a.foo += "";
-            if (a.foo) console.log("PASS");
-            else console.log("FAIL");
-        }();
-    }
-    expect: {
-        !function a() {
-            if (a.foo += "") console.log("PASS");
-            else console.log("FAIL");
-        }();
-    }
-    expect_stdout: "PASS"
-}
-
-set_mutable_2: {
-    options = {
-        cascade: true,
-        conditionals: true,
-        pure_getters: "strict",
-        reduce_vars: true,
-        sequences: true,
-        side_effects: true,
-    }
-    input: {
-        !function a() {
-            a.foo += "";
-            if (a.foo) console.log("PASS");
-            else console.log("FAIL");
-        }();
-    }
-    expect: {
-        !function a() {
-            (a.foo += "") ? console.log("PASS") : console.log("FAIL");
-        }();
-    }
-    expect_stdout: "PASS"
-}
-
-issue_2313_1: {
-    options = {
-        cascade: true,
-        conditionals: true,
-        pure_getters: "strict",
-        sequences: true,
-        side_effects: true,
-    }
-    input: {
-        function x() {
-            console.log(1);
-            return {
-                y: function() {
-                    console.log(2);
-                    return {
-                        z: 0
-                    };
-                }
-            };
-        }
-        x().y().z++;
-        if (x().y().z) {
-            console.log(3);
-        }
-    }
-    expect: {
-        function x() {
-            return console.log(1), {
-                y: function() {
-                    return console.log(2), {
-                        z: 0
-                    };
-                }
-            };
-        }
-        x().y().z++,
-        x().y().z && console.log(3);
-    }
-    expect_stdout: [
-        "1",
-        "2",
-        "1",
-        "2",
-    ]
-}
-
-issue_2313_2: {
-    options = {
-        cascade: true,
-        conditionals: true,
-        pure_getters: true,
-        sequences: true,
-        side_effects: true,
-    }
-    input: {
-        function x() {
-            console.log(1);
-            return {
-                y: function() {
-                    console.log(2);
-                    return {
-                        z: 0
-                    };
-                }
-            };
-        }
-        x().y().z++;
-        if (x().y().z) {
-            console.log(3);
-        }
-    }
-    expect: {
-        function x() {
-            return console.log(1), {
-                y: function() {
-                    return console.log(2), {
-                        z: 0
-                    };
-                }
-            };
-        }
-        x().y().z++,
-        x().y().z && console.log(3);
-    }
-    expect_stdout: [
-        "1",
-        "2",
-        "1",
-        "2",
-    ]
-}
-
-issue_2313_3: {
-    options = {
-        collapse_vars: true,
-        conditionals: true,
-        pure_getters: "strict",
-    }
-    input: {
-        function x() {
-            console.log(1);
-            return {
-                y: function() {
-                    console.log(2);
-                    return {
-                        z: 0
-                    };
-                }
-            };
-        }
-        x().y().z++;
-        if (x().y().z) {
-            console.log(3);
-        }
-    }
-    expect: {
-        function x() {
-            console.log(1);
-            return {
-                y: function() {
-                    console.log(2);
-                    return {
-                        z: 0
-                    };
-                }
-            };
-        }
-        x().y().z++;
-        x().y().z && console.log(3);
-    }
-    expect_stdout: [
-        "1",
-        "2",
-        "1",
-        "2",
-    ]
-}
-
-issue_2313_4: {
-    options = {
-        collapse_vars: true,
-        conditionals: true,
-        pure_getters: true,
-    }
-    input: {
-        function x() {
-            console.log(1);
-            return {
-                y: function() {
-                    console.log(2);
-                    return {
-                        z: 0
-                    };
-                }
-            };
-        }
-        x().y().z++;
-        if (x().y().z) {
-            console.log(3);
-        }
-    }
-    expect: {
-        function x() {
-            console.log(1);
-            return {
-                y: function() {
-                    console.log(2);
-                    return {
-                        z: 0
-                    };
-                }
-            };
-        }
-        x().y().z++;
-        x().y().z && console.log(3);
-    }
-    expect_stdout: [
-        "1",
-        "2",
-        "1",
-        "2",
-    ]
-}
-
-issue_2313_5: {
-    options = {
-        pure_getters: "strict",
-        side_effects: true,
-    }
-    input: {
-        x().y++;
-        x().y;
-    }
-    expect: {
-        x().y++;
-        x().y;
-    }
-}
-
-issue_2313_6: {
-    options = {
-        pure_getters: true,
-        side_effects: true,
-    }
-    input: {
-        x().y++;
-        x().y;
-    }
-    expect: {
-        x().y++;
-        x();
-    }
-}

test/compress/reduce_vars.js

@@ -2,7 +2,6 @@ reduce_vars: {
     options = {
         conditionals  : true,
         evaluate      : true,
-        inline        : true,
         global_defs   : {
             C : 0
         },
@@ -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: {
@@ -1469,7 +1435,6 @@ issue_1670_1: {
         reduce_vars: true,
         side_effects: true,
         switches: true,
-        typeofs: true,
         unused: true,
     }
     input: {
@@ -1533,7 +1498,6 @@ issue_1670_3: {
         reduce_vars: true,
         side_effects: true,
         switches: true,
-        typeofs: true,
         unused: true,
     }
     input: {
@@ -1723,7 +1687,6 @@ redefine_arguments_1: {
 redefine_arguments_2: {
     options = {
         evaluate: true,
-        inline: true,
         keep_fargs: false,
         reduce_vars: true,
         side_effects: true,
@@ -1760,7 +1723,6 @@ redefine_arguments_2: {
 redefine_arguments_3: {
     options = {
         evaluate: true,
-        inline: true,
         keep_fargs: false,
         passes: 3,
         reduce_vars: true,
@@ -1837,7 +1799,6 @@ redefine_farg_1: {
 redefine_farg_2: {
     options = {
         evaluate: true,
-        inline: true,
         keep_fargs: false,
         reduce_vars: true,
         side_effects: true,
@@ -1874,7 +1835,6 @@ redefine_farg_2: {
 redefine_farg_3: {
     options = {
         evaluate: true,
-        inline: true,
         keep_fargs: false,
         passes: 3,
         reduce_vars: true,
@@ -2230,11 +2190,10 @@ 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) {
@@ -2243,6 +2202,7 @@ issue_1814_1: {
         }();
     }
     expect: {
+        const a = 42;
         !function() {
             !function(a) {
                 console.log(a++, 42);
@@ -2256,11 +2216,10 @@ 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) {
@@ -2269,6 +2228,7 @@ issue_1814_2: {
         }();
     }
     expect: {
+        const a = "32";
         !function() {
             !function(a) {
                 console.log(a++, "321");
@@ -2577,28 +2537,3 @@ accessor: {
     }
     expect_stdout: "1 1"
 }
-
-for_in_prop: {
-    options = {
-        reduce_vars: true,
-    }
-    input: {
-        var a = {
-            foo: function() {
-                for (this.b in [1, 2]);
-            }
-        };
-        a.foo();
-        console.log(a.b);
-    }
-    expect: {
-        var a = {
-            foo: function() {
-                for (this.b in [1, 2]);
-            }
-        };
-        a.foo();
-        console.log(a.b);
-    }
-    expect_stdout: "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/screw-ie8.js

@@ -255,139 +255,3 @@ issue_1586_2: {
     }
     expect_exact: "function f(){try{x()}catch(c){console.log(c.message)}}"
 }
-
-issue_2120_1: {
-    mangle = {
-        ie8: false,
-    }
-    input: {
-        "aaaaaaaa";
-        var a = 1, b = "FAIL";
-        try {
-            throw 1;
-        } catch (c) {
-            try {
-                throw 0;
-            } catch (a) {
-                if (c) b = "PASS";
-            }
-        }
-        console.log(b);
-    }
-    expect: {
-        "aaaaaaaa";
-        var a = 1, b = "FAIL";
-        try {
-            throw 1;
-        } catch (t) {
-            try {
-                throw 0;
-            } catch (a) {
-                if (t) b = "PASS";
-            }
-        }
-        console.log(b);
-    }
-    expect_stdout: "PASS"
-}
-
-issue_2120_2: {
-    mangle = {
-        ie8: true,
-    }
-    input: {
-        "aaaaaaaa";
-        var a = 1, b = "FAIL";
-        try {
-            throw 1;
-        } catch (c) {
-            try {
-                throw 0;
-            } catch (a) {
-                if (c) b = "PASS";
-            }
-        }
-        console.log(b);
-    }
-    expect: {
-        "aaaaaaaa";
-        var a = 1, b = "FAIL";
-        try {
-            throw 1;
-        } catch (c) {
-            try {
-                throw 0;
-            } catch (a) {
-                if (c) b = "PASS";
-            }
-        }
-        console.log(b);
-    }
-    expect_stdout: "PASS"
-}
-
-issue_2254_1: {
-    mangle = {
-        ie8: false,
-    }
-    input: {
-        "eeeeee";
-        try {
-            console.log(f("PASS"));
-        } catch (e) {}
-        function f(s) {
-            try {
-                throw "FAIL";
-            } catch (e) {
-                return s;
-            }
-        }
-    }
-    expect: {
-        "eeeeee";
-        try {
-            console.log(f("PASS"));
-        } catch (e) {}
-        function f(e) {
-            try {
-                throw "FAIL";
-            } catch (t) {
-                return e;
-            }
-        }
-    }
-    expect_stdout: "PASS"
-}
-
-issue_2254_2: {
-    mangle = {
-        ie8: true,
-    }
-    input: {
-        "eeeeee";
-        try {
-            console.log(f("PASS"));
-        } catch (e) {}
-        function f(s) {
-            try {
-                throw "FAIL";
-            } catch (e) {
-                return s;
-            }
-        }
-    }
-    expect: {
-        "eeeeee";
-        try {
-            console.log(f("PASS"));
-        } catch (e) {}
-        function f(t) {
-            try {
-                throw "FAIL";
-            } catch (e) {
-                return t;
-            }
-        }
-    }
-    expect_stdout: "PASS"
-}

test/compress/sequences.js

@@ -176,11 +176,6 @@ for_sequences: {
         // 4
         x = (foo in bar);
         for (y = 5; false;);
-        // 5
-        x = function() {
-            foo in bar;
-        };
-        for (y = 5; false;);
     }
     expect: {
         // 1
@@ -193,10 +188,6 @@ for_sequences: {
         // 4
         x = (foo in bar);
         for (y = 5; false;);
-        // 5
-        for (x = function() {
-            foo in bar;
-        }, y = 5; false;);
     }
 }
 
@@ -720,63 +711,26 @@ issue_27: {
     }
 }
 
-issue_2062: {
-    options = {
-        booleans: true,
-        cascade: true,
-        conditionals: true,
-        side_effects: true,
-    }
-    input: {
-        var a = 1;
-        if ([ a || a++ + a--, a++ + a--, a && a.var ]);
-        console.log(a);
-    }
-    expect: {
-        var a = 1;
-        a || (a++, a--), a++, --a && a.var;
-        console.log(a);
-    }
-    expect_stdout: "1"
-}
-
-issue_2313: {
+reassign_const: {
     options = {
         cascade: true,
         sequences: true,
         side_effects: true,
     }
     input: {
-        var a = 0, b = 0;
-        var foo = {
-            get c() {
-                a++;
-                return 42;
-            },
-            set c(c) {
-                b++;
-            },
-            d: function() {
-                this.c++;
-                if (this.c) console.log(a, b);
-            }
+        function f() {
+            const a = 1;
+            a++;
+            return a;
         }
-        foo.d();
+        console.log(f());
     }
     expect: {
-        var a = 0, b = 0;
-        var foo = {
-            get c() {
-                return a++, 42;
-            },
-            set c(c) {
-                b++;
-            },
-            d: function() {
-                if (this.c++, this.c) console.log(a, b);
-            }
+        function f() {
+            const a = 1;
+            return a++, a;
         }
-        foo.d();
+        console.log(f());
     }
-    expect_stdout: "2 1"
+    expect_stdout: true
 }

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

@@ -16,42 +16,105 @@ unicode_parse_variables: {
     }
 }
 
-issue_2242_1: {
-    beautify = {
-        ascii_only: false,
-    }
+unicode_escaped_identifier: {
+    beautify = {ecma: 6}
     input: {
-        console.log("\ud83d", "\ude00", "\ud83d\ude00", "\ud83d@\ude00");
+        var \u{61} = "foo";
+        var \u{10000} = "bar";
     }
-    expect_exact: 'console.log("\\ud83d","\\ude00","\ud83d\ude00","\\ud83d@\\ude00");'
+    expect_exact: 'var a="foo";var \u{10000}="bar";';
 }
 
-issue_2242_2: {
-    beautify = {
-        ascii_only: true,
-    }
+unicode_identifier_ascii_only: {
+    beautify = {ascii_only: true, ecma: 6}
     input: {
-        console.log("\ud83d", "\ude00", "\ud83d\ude00", "\ud83d@\ude00");
+        var \u{0061} = "hi";
+        var bar = "h\u{0065}llo";
+        var \u{10000} = "testing \u{101111}";
     }
-    expect_exact: 'console.log("\\ud83d","\\ude00","\\ud83d\\ude00","\\ud83d@\\ude00");'
+    expect_exact: 'var a="hi";var bar="hello";var \\u{10000}="testing \\u{101111}";'
 }
 
-issue_2242_3: {
-    options = {
-        evaluate: false,
-    }
+unicode_string_literals: {
+    beautify = {ascii_only: true, ecma: 6}
     input: {
-        console.log("\ud83d" + "\ude00", "\ud83d" + "@" + "\ude00");
+        var a = "6 length unicode character: \u{101111}";
     }
-    expect_exact: 'console.log("\\ud83d"+"\\ude00","\\ud83d"+"@"+"\\ude00");'
+    expect_exact: 'var a="6 length unicode character: \\u{101111}";'
 }
 
-issue_2242_4: {
-    options = {
-        evaluate: true,
-    }
+// 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: {
-        console.log("\ud83d" + "\ude00", "\ud83d" + "@" + "\ude00");
+        var \u{10000} = "6 length unicode character: \u{10FFFF}";
     }
-    expect_exact: 'console.log("\ud83d\ude00","\\ud83d@\\ude00");'
+    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/exports.js

@@ -8,7 +8,6 @@ exports["defaults"] = defaults;
 exports["mangle_properties"] = mangle_properties;
 exports["minify"] = minify;
 exports["parse"] = parse;
-exports["reserve_quoted_keys"] = reserve_quoted_keys;
 exports["string_template"] = string_template;
 exports["tokenizer"] = tokenizer;
 exports["is_identifier"] = is_identifier;

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/for-in_1.js

@@ -1,4 +0,0 @@
-var a, b = [1, 2];
-for (1, 2, a in b) {
-    console.log(a, b[a]);
-}

test/input/invalid/for-in_2.js

@@ -1,4 +0,0 @@
-var c = [1, 2];
-for (var a, b in c) {
-    console.log(a, c[a]);
-}

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-2310/input.js

@@ -1,10 +0,0 @@
-function foo() {
-    return function() {
-        console.log("PASS");
-    };
-}
-
-(function() {
-    var f = foo();
-    f();
-})();

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();
         });
@@ -63,7 +61,7 @@ describe("bin/uglifyjs", function () {
             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,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFJQSxJQUFNLFdBQ04sU0FBU0MsSUFBS0QsS0FDVixPQUFPQSxJQUdYLE9BQU9DLElBTEQifQ==\n");
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxHQUFJQSxLQUFNLFdBQ04sUUFBU0MsS0FBS0QsS0FDVixNQUFPQSxLQUdYLE1BQU9DIn0=\n");
             done();
         });
     });
@@ -77,23 +75,6 @@ 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';
 
@@ -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,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFJQSxJQUFNLFdBQ04sU0FBU0MsSUFBS0QsS0FDVixPQUFPQSxJQUdYLE9BQU9DLElBTEQifQ==",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxHQUFJQSxLQUFNLFdBQ04sUUFBU0MsS0FBS0QsS0FDVixNQUFPQSxLQUdYLE1BQU9DIn0=",
                 "",
             ].join("\n"));
             assert.strictEqual(stderr, "WARN: inline source map not found\n");
@@ -398,6 +379,21 @@ describe("bin/uglifyjs", function () {
             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';
 
@@ -468,7 +464,7 @@ describe("bin/uglifyjs", function () {
                 "Parse error at test/input/invalid/try.js:7,18",
                 "    try {} catch (eval) {}",
                 "                  ^",
-                "ERROR: Unexpected eval in strict mode"
+                "ERROR: Unexpected eval identifier as parameter inside strict mode"
             ].join("\n"));
             done();
         });
@@ -518,36 +514,6 @@ describe("bin/uglifyjs", function () {
             done();
         });
     });
-    it("Should throw syntax error (for-in init)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/for-in_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/for-in_1.js:2,5",
-                "for (1, 2, a in b) {",
-                "     ^",
-                "ERROR: Invalid left-hand side in for..in loop"
-            ].join("\n"));
-            done();
-        });
-    });
-    it("Should throw syntax error (for-in var)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/for-in_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/for-in_2.js:2,5",
-                "for (var a, b in c) {",
-                "     ^",
-                "ERROR: Only one variable declaration allowed in for..in loop"
-            ].join("\n"));
-            done();
-        });
-    });
     it("Should handle literal string as source map input", function(done) {
         var command = [
             uglifyjscmd,
@@ -561,7 +527,7 @@ 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();
@@ -573,25 +539,6 @@ describe("bin/uglifyjs", function () {
             return JSON.stringify(map).replace(/"/g, '\\"');
         }
     });
-    it("Should include function calls in source map", function(done) {
-        var command = [
-            uglifyjscmd,
-            "test/input/issue-2310/input.js",
-            "-c",
-            "--source-map", "url=inline",
-        ].join(" ");
-
-        exec(command, function(err, stdout, stderr) {
-            if (err) throw err;
-
-            assert.strictEqual(stdout, [
-                'function foo(){return function(){console.log("PASS")}}foo()();',
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMjMxMC9pbnB1dC5qcyJdLCJuYW1lcyI6WyJmb28iLCJjb25zb2xlIiwibG9nIiwiZiJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0EsTUFDTCxPQUFPLFdBQ0hDLFFBQVFDLElBQUksU0FLUkYsS0FDUkcifQ==",
-                ""
-            ].join("\n"));
-            done();
-        });
-    });
     it("Should dump AST as JSON", function(done) {
         var command = uglifyjscmd + " test/input/global_defs/simple.js -mco ast";
         exec(command, function (err, stdout) {
@@ -603,51 +550,4 @@ 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();
-        });
-    });
-    it("Should fail with --mangle-props reserved=[in]", function(done) {
-        var command = uglifyjscmd + " test/input/issue-505/input.js --mangle-props reserved=[in]";
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.ok(/^Supported options:\n[\s\S]*?\nERROR: `reserved=\[in]` is not a supported option/.test(stderr), stderr);
-            done();
-        });
-    });
-    it("Should fail with --define a-b", function(done) {
-        var command = uglifyjscmd + " test/input/issue-505/input.js --define a-b";
-        exec(command, function (err, stdout, stderr) {
-            assert.ok(err);
-            assert.strictEqual(stdout, "");
-            assert.strictEqual(stderr, "Error parsing arguments for 'define': a-b\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"]
             }
         ];
 
@@ -378,4 +388,44 @@ describe("Directives", function() {
             );
         }
     });
+    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]);
+        }
+    });
+});