v3.13.5

fixes #4876

.github/ISSUE_TEMPLATE.md

@@ -1,20 +0,0 @@
-**Bug report or feature request?** 
-
-<!-- Note: sub-optimal but correct code is not a bug -->
-
-**ES5 or ES6+ input?** 
-
-<!-- Note: for ES6 see: https://github.com/mishoo/UglifyJS2/tree/harmony#harmony -->
-
-**Uglify version (`uglifyjs -V`)**
-
-**JavaScript input**  <!-- ideally as small as possible -->
-
-**The `uglifyjs` CLI command executed or `minify()` options used.**
-
-**JavaScript output or error produced.**
-
-<!--
-    Note: `uglify-js` only supports ES5. 
-    Those wishing to minify ES6 should use `uglify-es`.
--->

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,51 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+<!-- Note: sub-optimal but correct code is not a bug -->
+
+**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, but may be large if isolating
+the problem proves to be difficult. The most important thing is that the
+standalone program reliably exhibits the bug when minified. Provide a link to a
+gist if necessary.
+
+Solely providing minified output without the original uglify JS input is not
+useful in determining the cause of the problem. Issues without a reproducible
+test case will be closed.
+-->
+
+**The `uglifyjs` CLI command executed or `minify()` options used.**
+
+<!--
+Command-line or API call to UglifyJS without third party tools or libraries.
+
+For users using bundlers or transpilers, you may be able to gather the required
+information through setting the `UGLIFY_BUG_REPORT` environment variable:
+
+    export UGLIFY_BUG_REPORT=1      (bash)
+    set UGLIFY_BUG_REPORT=1         (Command Prompt)
+    $Env:UGLIFY_BUG_REPORT=1        (PowerShell)
+
+before running your usual build process. The resulting "minified" output should
+contain the necessary details for this report.
+-->
+
+**JavaScript output or error produced.**
+
+<!--
+Only minified code that produces different output (or error) from the original
+upon execution would be considered a bug.
+-->

.github/workflows/build.yml

@@ -0,0 +1,58 @@
+name: Build testing
+on:
+  pull_request:
+  push:
+    branches: [ master ]
+jobs:
+  ufuzz:
+    strategy:
+      fail-fast: false
+      matrix:
+        options:
+          - '-mb braces'
+          - '--ie8 -c'
+          - '-mc'
+          - '-p acorn --toplevel -mco spidermonkey'
+          - '--toplevel -mc passes=3,pure_getters,unsafe'
+        script:
+          - acorn.sh
+          - bootstrap.sh
+          - buble.sh
+          - butternut.sh
+          - mathjs.sh
+          - rollup-es.sh
+          - rollup-ts.sh
+          - sucrase.sh
+          - web-tooling-benchmark.sh
+        include:
+          - node: '14'
+            script: acorn.sh
+          - node: '14'
+            script: bootstrap.sh
+          - node: '14'
+            script: buble.sh
+          - node: '14'
+            script: butternut.sh
+          - node: '14'
+            script: mathjs.sh
+          - node: '8'
+            script: rollup-es.sh
+          - node: '14'
+            script: rollup-ts.sh
+          - node: '14'
+            script: sucrase.sh
+          - node: '14'
+            script: web-tooling-benchmark.sh
+    name: ${{ matrix.script }} ${{ matrix.options }}
+    runs-on: ubuntu-latest
+    env:
+      NODE: ${{ matrix.node }}
+      OPTIONS: ${{ matrix.options }}
+      SCRIPT: ${{ matrix.script }}
+    steps:
+      - uses: actions/checkout@v2
+      - name: Perform uglify, build & test
+        shell: bash
+        run: |
+          . ./test/release/install.sh
+          ./test/release/$SCRIPT $OPTIONS

.github/workflows/ci.yml

@@ -0,0 +1,33 @@
+name: CI
+on:
+  pull_request:
+  push:
+    branches: [ master ]
+jobs:
+  test:
+    strategy:
+      matrix:
+        node: [ '0.8', '0.10', '0.12', '4', '6', '8', '10', '12', '14', latest ]
+        os: [ ubuntu-latest, windows-latest ]
+        script: [ compress, mocha, release/benchmark, release/jetstream ]
+        exclude:
+          - node: '0.8'
+            script: release/benchmark
+          - node: '0.8'
+            script: release/jetstream
+    name: ${{ matrix.node }} ${{ matrix.os }} ${{ matrix.script }}
+    runs-on: ${{ matrix.os }}
+    env:
+      NODE: ${{ matrix.node }}
+      TYPE: ${{ matrix.script }}
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/cache@v2
+        with:
+          path: tmp
+          key: tmp ${{ matrix.script }}
+      - name: Perform tests
+        shell: bash
+        run: |
+          . ./test/release/install.sh
+          node test/$TYPE

.github/workflows/ufuzz.yml

@@ -0,0 +1,41 @@
+name: Fuzzing
+on:
+  pull_request:
+  schedule:
+    - cron: '*/5 * * * *'
+env:
+  BASE_URL: https://api.github.com/repos/${{ github.repository }}
+  CAUSE: ${{ github.event_name }}
+  RUN_NUM: ${{ github.run_number }}
+  TOKEN: ${{ github.token }}
+jobs:
+  ufuzz:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - node: latest
+            os: macos-latest
+          - node: '8'
+            os: ubuntu-latest
+          - node: '8'
+            os: ubuntu-latest
+          - node: '8'
+            os: windows-latest
+          - node: '8'
+            os: windows-latest
+    name: ${{ matrix.node }} ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    env:
+      NODE: ${{ matrix.node }}
+    steps:
+      - uses: actions/checkout@v2
+      - name: Perform fuzzing
+        shell: bash
+        run: |
+          . ./test/release/install.sh
+          if [[ $CAUSE == "schedule" ]]; then
+            node test/ufuzz/job $BASE_URL $TOKEN $RUN_NUM
+          else
+            node test/ufuzz/job 5000
+          fi

.travis.yml

@@ -1,11 +0,0 @@
-language: node_js
-node_js:
-    - "0.10"
-    - "0.12"
-    - "4"
-    - "6"
-env:
-    - UGLIFYJS_TEST_ALL=1
-matrix:
-  fast_finish: true
-sudo: false

CONTRIBUTING.md

@@ -0,0 +1,61 @@
+Contributing
+============
+
+## Documentation
+
+Every new feature and API change should be accompanied by a README additon.
+
+## Testing
+
+All features and bugs should have tests that verify the fix. You can run all
+tests using `npm test`.
+
+The most common type of test are tests that verify input and output of the
+Uglify transforms. These tests exist in `test/compress`. New tests can be added
+either to an existing file or in a new file `issue-xxx.js`.
+
+Tests that cannot be expressed as a simple AST can be found in `test/mocha`.
+
+## Code style
+
+- File encoding must be `UTF-8`.
+- `LF` is always used as a line ending.
+- Statements end with semicolons.
+- Indentation uses 4 spaces, switch `case` 2 spaces.
+- Identifiers use `snake_case`.
+- Strings use double quotes (`"`).
+- Use a trailing comma for multiline array and object literals to minimize diffs.
+- The Uglify code only uses ES5, even in the `harmony` branch.
+- Line length should be at most 80 cols, except when it is easier to read a
+  longer line.
+- If both sides of a comparison are of the same type, `==` and `!=` are used.
+- Multiline conditions place `&&` and `||` first on the line.
+
+**Example feature**
+
+```js
+OPT(AST_Debugger, function(self, compressor) {
+    if (compressor.option("drop_debugger"))
+        return make_node(AST_EmptyStatement, self);
+    return self;
+});
+```
+
+**Example test case**
+
+```js
+drop_debugger: {
+    options = {
+        drop_debugger: true,
+    }
+    input: {
+        debugger;
+        if (foo) debugger;
+    }
+    expect: {
+        if (foo);
+    }
+}
+```
+
+

LICENSE

@@ -1,6 +1,6 @@
 UglifyJS is released under the BSD license:
 
-Copyright 2012-2013 (c) Mihai Bazon <mihai.bazon@gmail.com>
+Copyright 2012-2019 (c) Mihai Bazon <mihai.bazon@gmail.com>
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions

README.md

@@ -4,11 +4,11 @@ UglifyJS 3
 UglifyJS is a JavaScript 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).
+- `uglify-js` supports JavaScript and most language features in ECMAScript.
+- For more exotic parts of ECMAScript, process your source file with transpilers
+  like [Babel](https://babeljs.io/) before passing onto `uglify-js`.
+- `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/UglifyJS/tree/v2.x).
 
 Install
 -------
@@ -70,7 +70,7 @@ a double dash to prevent input files being used as option arguments:
                                 `debug`  Add debug prefix and suffix.
                                 `domprops`  Mangle property names that overlaps
                                             with DOM properties.
-                                `keep_quoted`  Only mangle unquoted properies.
+                                `keep_quoted`  Only mangle unquoted properties.
                                 `regex`  Only mangle matched property names.
                                 `reserved`  List of names that should not be mangled.
     -b, --beautify [options]    Beautify output/specify output options:
@@ -85,12 +85,16 @@ a double dash to prevent input files being used as option arguments:
                                                1 - single
                                                2 - double
                                                3 - original
-                                `wrap_iife`  Wrap IIFEs in parenthesis. Note: you may
+                                `wrap_iife`  Wrap IIFEs in parentheses. Note: you may
                                              want to disable `negate_iife` under
                                              compressor options.
+    -O, --output-opts [options] Specify output options (`beautify` disabled by default).
     -o, --output <file>         Output file path (default STDOUT). Specify `ast` or
                                 `spidermonkey` to write UglifyJS or SpiderMonkey AST
                                 as JSON to STDOUT respectively.
+    --annotations               Process and preserve comment annotations.
+                                (`/*@__PURE__*/` or `/*#__PURE__*/`)
+    --no-annotations            Ignore and discard comment annotations.
     --comments [filter]         Preserve copyright comments in the output. By
                                 default this works like Google Closure, keeping
                                 JSDoc-style comments that contain "@license" or
@@ -105,13 +109,15 @@ a double dash to prevent input files being used as option arguments:
                                 sequences.
     --config-file <file>        Read `minify()` options from JSON file.
     -d, --define <expr>[=value] Global definitions.
+    -e, --enclose [arg[:value]] Embed everything in a big function, with configurable
+                                argument(s) & value(s).
     --ie8                       Support non-standard Internet Explorer 8.
                                 Equivalent to setting `ie8: true` in `minify()`
                                 for `compress`, `mangle` and `output` options.
                                 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 to hold mangled name mappings.
+    --name-cache <file>         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.
@@ -119,18 +125,28 @@ a double dash to prevent input files being used as option arguments:
                                            JS that was generated from some other original
                                            code. Specify "inline" if the source map is
                                            included within the sources.
-                                `filename`  Name and/or location of the output source.
+                                `filename`  Filename and/or location of the output source
+                                            (sets `file` attribute in source map).
                                 `includeSources`  Pass this flag if you want to include
                                                   the content of source files in the
                                                   source map as sourcesContent property.
+                                `names` Include symbol names in the source map.
                                 `root`  Path to the original source to be included in
                                         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.
+    --v8                        Support non-standard Chrome & Node.js
+                                Equivalent to setting `v8: true` in `minify()`
+                                for `mangle` and `output` options.
+                                By default UglifyJS will not try to be v8-proof.
     --verbose                   Print diagnostic messages.
     --warn                      Print warning messages.
+    --webkit                    Support non-standard Safari/Webkit.
+                                Equivalent to setting `webkit: true` in `minify()`
+                                for `mangle` and `output` options.
+                                By default UglifyJS will not try to be Safari-proof.
     --wrap <name>               Embed everything in a big function, making the
                                 “exports” and “global” variables available. You
                                 need to pass an argument to this option to
@@ -150,19 +166,24 @@ 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. The value of
+  `filename` is only used to set `file` attribute (see [the spec][sm-spec])
+  in source map file.
 
-- `--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.
+
+- `--source-map "names=false"` to omit symbol names if you want to reduce size
+  of the source map file.
+
+- `--source-map "url='<URL>'"` to specify the URL where the source map 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.
-
 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 +202,8 @@ 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
@@ -203,19 +224,16 @@ 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
-  default).
+- `eval` (default: `false`) — mangle names visible in scopes where `eval` or
+  `with` are used.
 
-- `eval` — mangle names visible in scopes where `eval` or `with` are used
-  (disabled by default).
+- `reserved` (default: `[]`) — 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:
 
-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.
+  to prevent the `require`, `exports` and `$` names from being changed.
 
 ### CLI mangling property names (`--mangle-props`)
 
@@ -223,7 +241,7 @@ to prevent the `require`, `exports` and `$` names from being changed.
 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:
+in core JavaScript classes.  For example:
 
 ```javascript
 // example.js
@@ -238,7 +256,7 @@ x.bar_ = 2;
 x["baz_"] = 3;
 console.log(x.calc());
 ```
-Mangle all properties (except for javascript `builtins`):
+Mangle all properties (except for JavaScript `builtins`):
 ```bash
 $ uglifyjs example.js -c -m --mangle-props
 ```
@@ -383,7 +401,47 @@ var code = {
 var options = { toplevel: true };
 var result = UglifyJS.minify(code, options);
 console.log(result.code);
-// console.log(function(n,o){return n+o}(3,7));
+// 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:
@@ -436,38 +494,57 @@ 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.
+- `annotations` — pass `false` to ignore all comment annotations and elide them
+  from output. Useful when, for instance, external tools incorrectly applied
+  `/*@__PURE__*/` or `/*#__PURE__*/`. Pass `true` to both compress and retain
+  comment annotations in output to allow for further processing downstream.
 
-- `parse` (default `{}`) — pass an object if you wish to specify some
-  additional [parse options](#parse-options).
-
-- `compress` (default `{}`) — pass `false` to skip compressing entirely.
+- `compress` (default: `{}`) — pass `false` to skip compressing entirely.
   Pass an object to specify custom [compress options](#compress-options).
 
-- `mangle` (default `true`) — pass `false` to skip mangling names, or pass
+- `ie8` (default: `false`) — set to `true` to support IE8.
+
+- `keep_fnames` (default: `false`) — pass `true` to prevent discarding or mangling
+  of function names.  Useful for code relying on `Function.prototype.name`.
+
+- `mangle` (default: `true`) — pass `false` to skip mangling names, or pass
   an object to specify [mangle options](#mangle-options) (see below).
 
-  - `mangle.properties` (default `false`) — a subcategory of the mangle option.
+  - `mangle.properties` (default: `false`) — a subcategory of the mangle option.
     Pass an object to specify custom [mangle property options](#mangle-properties-options).
 
-- `output` (default `null`) — pass an object if you wish to specify
+- `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.
+
+- `output` (default: `null`) — pass an object if you wish to specify
   additional [output options](#output-options).  The defaults are optimized
   for best compression.
 
-- `sourceMap` (default `false`) - pass an object if you wish to specify
+- `parse` (default: `{}`) — pass an object if you wish to specify some
+  additional [parse options](#parse-options).
+
+- `sourceMap` (default: `false`) — pass an object if you wish to specify
   [source map options](#source-map-options).
 
-- `toplevel` (default `false`) - set to `true` if you wish to enable top level
+- `toplevel` (default: `false`) — set to `true` if you wish to enable top level
   variable and function name mangling and to drop unused variables and functions.
 
-- `ie8` (default `false`) - set to `true` to support IE8.
+- `v8` (default: `false`) — enable workarounds for Chrome & Node.js bugs.
+
+- `warnings` (default: `false`) — pass `true` to return compressor warnings
+  in `result.warnings`. Use the value `"verbose"` for more detailed warnings.
+
+- `webkit` (default: `false`) — enable workarounds for Safari/WebKit bugs.
+  PhantomJS users should set this option to `true`.
 
 ## Minify options structure
 
 ```javascript
 {
-    warnings: false,
     parse: {
         // parse options
     },
@@ -487,8 +564,10 @@ if (result.error) throw result.error;
     sourceMap: {
         // source map options
     },
+    nameCache: null, // or specify a name cache object
     toplevel: false,
     ie8: false,
+    warnings: false,
 }
 ```
 
@@ -539,107 +618,126 @@ var result = UglifyJS.minify({"compiled.js": "compiled code"}, {
 
 If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.url`.
 
+If you wish to reduce file size of the source map, set option `sourceMap.names`
+to be `false` and all symbol names will be omitted.
+
 ## Parse options
 
-- `bare_returns` (default `false`) -- support top level `return` statements
-- `html5_comments` (default `true`)
-- `shebang` (default `true`) -- support `#!command` as the first line
+- `bare_returns` (default: `false`) — support top level `return` statements
+
+- `html5_comments` (default: `true`)
+
+- `shebang` (default: `true`) — support `#!command` as the first line
 
 ## Compress options
 
-- `sequences` (default: true) -- join consecutive simple statements using the
-  comma operator.  May be set to a positive integer to specify the maximum number
-  of consecutive comma sequences that will be generated. If this option is set to
-  `true` then the default `sequences` limit is `200`. Set option to `false` or `0`
-  to disable. The smallest `sequences` length is `2`. A `sequences` value of `1`
-  is grandfathered to be equivalent to `true` and as such means `200`. On rare
-  occasions the default sequences limit leads to very slow compress times in which
-  case a value of `20` or less is recommended.
+- `annotations` (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();`
 
-- `properties` -- rewrite property access using the dot notation, for
-  example `foo["bar"] → foo.bar`
+- `arguments` (default: `true`) — replace `arguments[index]` with function
+  parameter name whenever possible.
 
-- `dead_code` -- remove unreachable code
+- `arrows` (default: `true`) — apply optimizations to arrow functions
 
-- `drop_debugger` -- remove `debugger;` statements
+- `assignments` (default: `true`) — apply optimizations to assignment expressions
 
-- `unsafe` (default: false) -- apply "unsafe" transformations (discussion below)
+- `awaits` (default: `true`) — apply optimizations to `await` expressions
 
-- `unsafe_comps` (default: false) -- Reverse `<` and `<=` to `>` and `>=` to
-  allow improved compression. This might be unsafe when an at least one of two
-  operands is an object with computed values due the use of methods like `get`,
-  or `valueOf`. This could cause change in execution order after operands in the
-  comparison are switching. Compression only works if both `comparisons` and
-  `unsafe_comps` are both set to true.
+- `booleans` (default: `true`) — various optimizations for boolean context,
+  for example `!!a ? b : c → a ? b : c`
 
-- `unsafe_Func` (default: false) -- compress and mangle `Function(args, code)`.
+- `collapse_vars` (default: `true`) — Collapse single-use non-constant variables,
+  side effects permitting.
 
-- `unsafe_math` (default: false) -- optimize numerical expressions like
-  `2 * x * 3` into `6 * x`, which may give imprecise floating point results.
+- `comparisons` (default: `true`) — apply certain optimizations to binary nodes,
+  e.g. `!(a <= b) → a > b`, attempts to negate binary nodes, e.g.
+  `a = !b && !c && !d && !e → a=!(b||c||d||e)` etc.
 
-- `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
+- `conditionals` (default: `true`) — apply optimizations for `if`-s and conditional
   expressions
 
-- `comparisons` -- apply certain optimizations to binary nodes, for example:
-  `!(a <= b) → a > b` (only when `unsafe_comps`), attempts to negate binary
-  nodes, e.g. `a = !b && !c && !d && !e → a=!(b||c||d||e)` etc.
+- `dead_code` (default: `true`) — remove unreachable code
 
-- `evaluate` -- attempt to evaluate constant expressions
+- `default_values` (default: `true`) — drop overshadowed default values
 
-- `booleans` -- various optimizations for boolean context, for example `!!a
-  ? b : c → a ? b : c`
+- `directives` (default: `true`) — remove redundant or non-standard directives
 
-- `loops` -- optimizations for `do`, `while` and `for` loops when we can
-  statically determine the condition
+- `drop_console` (default: `false`) — Pass `true` to discard calls to
+  `console.*` functions. If you wish to drop a specific function call
+  such as `console.info` and/or retain side effects from function arguments
+  after dropping the function call then use `pure_funcs` instead.
 
-- `unused` -- drop unreferenced functions and variables (simple direct variable
-  assignments do not count as references unless set to `"keep_assign"`)
+- `drop_debugger` (default: `true`) — remove `debugger;` statements
 
-- `toplevel` -- drop unreferenced functions (`"funcs"`) and/or variables (`"vars"`)
-  in the top level scope (`false` by default, `true` to drop both unreferenced
-  functions and variables)
+- `evaluate` (default: `true`) — Evaluate expression for shorter constant
+  representation. Pass `"eager"` to always replace function calls whenever
+  possible, or a positive integer to specify an upper bound for each individual
+  evaluation in number of characters.
 
-- `top_retain` -- prevent specific toplevel functions and variables from `unused`
-  removal (can be array, comma-separated, RegExp or function. Implies `toplevel`)
+- `expression` (default: `false`) — Pass `true` to preserve completion values
+  from terminal statements without `return`, e.g. in bookmarklets.
 
-- `hoist_funs` -- hoist function declarations
+- `functions` (default: `true`) — convert declarations from `var` to `function`
+  whenever possible.
 
-- `hoist_vars` (default: false) -- hoist `var` declarations (this is `false`
+- `global_defs` (default: `{}`) — see [conditional compilation](#conditional-compilation)
+
+- `hoist_exports` (default: `true`) — hoist `export` statements to facilitate
+  various `compress` and `mangle` optimizations.
+
+- `hoist_funs` (default: `false`) — hoist function declarations
+
+- `hoist_props` (default: `true`) — hoist properties from constant object and
+  array literals into regular variables subject to a set of constraints. For example:
+  `var o={p:1, q:2}; f(o.p, o.q);` is converted to `f(1, 2);`. Note: `hoist_props`
+  works best with `toplevel` and `mangle` enabled, alongside with `compress` option
+  `passes` set to `2` or higher.
+
+- `hoist_vars` (default: `false`) — hoist `var` declarations (this is `false`
   by default because it seems to increase the size of the output in general)
 
-- `if_return` -- optimizations for if/return and if/continue
+- `if_return` (default: `true`) — optimizations for if/return and if/continue
 
-- `join_vars` -- join consecutive `var` statements
+- `imports` (default: `true`) — drop unreferenced import symbols when used with `unused`
 
-- `cascade` -- small optimization for sequences, transform `x, x` into `x`
-  and `x = something(), x` into `x = something()`
+- `inline` (default: `true`) — inline calls to function with simple/`return` statement:
+  - `false` — same as `0`
+  - `0` — disabled inlining
+  - `1` — inline simple functions
+  - `2` — inline functions with arguments
+  - `3` — inline functions with arguments and variables
+  - `true` — same as `3`
 
-- `collapse_vars` -- Collapse single-use non-constant variables - side
-  effects permitting.
+- `join_vars` (default: `true`) — join consecutive `var` statements
 
-- `reduce_vars` -- Improve optimization on variables assigned with and
-  used as constant values.
+- `keep_fargs` (default: `false`) — discard unused function arguments except
+  when unsafe to do so, e.g. code which relies on `Function.prototype.length`.
+  Pass `true` to always retain function arguments.
 
-- `warnings` -- display warnings when dropping unreachable code or unused
-  declarations etc.
+- `keep_infinity` (default: `false`) — Pass `true` to prevent `Infinity` from
+  being compressed into `1/0`, which may cause performance issues on Chrome.
 
-- `negate_iife` -- negate "Immediately-Called Function Expressions"
+- `loops` (default: `true`) — optimizations for `do`, `while` and `for` loops
+  when we can statically determine the condition.
+
+- `merge_vars` (default: `true`) — combine and reuse variables.
+
+- `negate_iife` (default: `true`) — negate "Immediately-Called Function Expressions"
   where the return value is discarded, to avoid the parens that the
   code generator would insert.
 
-- `pure_getters` -- the default is `false`.  If you pass `true` for
-  this, UglifyJS will assume that object property access
-  (e.g. `foo.bar` or `foo["bar"]`) doesn't have any side effects.
-  Specify `"strict"` to treat `foo.bar` as side-effect-free only when
-  `foo` is certain to not throw, i.e. not `null` or `undefined`.
+- `objects` (default: `true`) — compact duplicate keys in object literals.
 
-- `pure_funcs` -- default `null`.  You can pass an array of names and
+- `passes` (default: `1`) — The maximum number of times to run compress.
+  In some cases more than one pass leads to further compressed code.  Keep in
+  mind more passes will take more time.
+
+- `properties` (default: `true`) — rewrite property access using the dot notation, for
+  example `foo["bar"] → foo.bar`
+
+- `pure_funcs` (default: `null`) — You can pass an array of names and
   UglifyJS will assume that those functions do not produce side
   effects.  DANGER: will not check if the name is redefined in scope.
   An example case here, for instance `var q = Math.floor(a/b)`.  If
@@ -648,51 +746,99 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   pass `pure_funcs: [ 'Math.floor' ]` to let it know that this
   function won't produce any side effect, in which case the whole
   statement would get discarded.  The current implementation adds some
-  overhead (compression will be slower).
+  overhead (compression will be slower). Make sure symbols under `pure_funcs`
+  are also under `mangle.reserved` to avoid mangling.
 
-- `drop_console` -- default `false`.  Pass `true` to discard calls to
-  `console.*` functions. If you wish to drop a specific function call
-  such as `console.info` and/or retain side effects from function arguments
-  after dropping the function call then use `pure_funcs` instead.
+- `pure_getters` (default: `"strict"`) — If you pass `true` for
+  this, UglifyJS will assume that object property access
+  (e.g. `foo.bar` or `foo["bar"]`) doesn't have any side effects.
+  Specify `"strict"` to treat `foo.bar` as side-effect-free only when
+  `foo` is certain to not throw, i.e. not `null` or `undefined`.
 
-- `expression` -- default `false`.  Pass `true` to preserve completion values
-  from terminal statements without `return`, e.g. in bookmarklets.
+- `reduce_funcs` (default: `true`) — Allows single-use functions to be
+  inlined as function expressions when permissible allowing further
+  optimization.  Enabled by default.  Option depends on `reduce_vars`
+  being enabled.  Some code runs faster in the Chrome V8 engine if this
+  option is disabled.  Does not negatively impact other major browsers.
 
-- `keep_fargs` -- default `true`.  Prevents the
-  compressor from discarding unused function arguments.  You need this
-  for code which relies on `Function.length`.
+- `reduce_vars` (default: `true`) — Improve optimization on variables assigned with and
+  used as constant values.
 
-- `keep_fnames` -- default `false`.  Pass `true` to prevent the
-  compressor from discarding function names.  Useful for code relying on
-  `Function.prototype.name`. See also: the `keep_fnames` [mangle option](#mangle).
+- `rests` (default: `true`) — apply optimizations to rest parameters
 
-- `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.
+- `sequences` (default: `true`) — join consecutive simple statements using the
+  comma operator.  May be set to a positive integer to specify the maximum number
+  of consecutive comma sequences that will be generated. If this option is set to
+  `true` then the default `sequences` limit is `200`. Set option to `false` or `0`
+  to disable. The smallest `sequences` length is `2`. A `sequences` value of `1`
+  is grandfathered to be equivalent to `true` and as such means `200`. On rare
+  occasions the default sequences limit leads to very slow compress times in which
+  case a value of `20` or less is recommended.
 
-- `keep_infinity` -- default `false`. Pass `true` to prevent `Infinity` from
-  being compressed into `1/0`, which may cause performance issues on Chrome.
+- `side_effects` (default: `true`) — drop extraneous code which does not affect
+  outcome of runtime execution.
 
-- `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();`
+- `spreads` (default: `true`) — flatten spread expressions.
+
+- `strings` (default: `true`) — compact string concatenations.
+
+- `switches` (default: `true`) — de-duplicate and remove unreachable `switch` branches
+
+- `templates` (default: `true`) — compact template literals by embedding expressions
+  and/or converting to string literals, e.g. `` `foo ${42}` → "foo 42"``
+
+- `top_retain` (default: `null`) — prevent specific toplevel functions and
+  variables from `unused` removal (can be array, comma-separated, RegExp or
+  function. Implies `toplevel`)
+
+- `toplevel` (default: `false`) — drop unreferenced functions (`"funcs"`) and/or
+  variables (`"vars"`) in the top level scope (`false` by default, `true` to drop
+  both unreferenced functions and variables)
+
+- `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.
+
+- `unsafe` (default: `false`) — apply "unsafe" transformations (discussion below)
+
+- `unsafe_comps` (default: `false`) — compress expressions like `a <= b` assuming
+  none of the operands can be (coerced to) `NaN`.
+
+- `unsafe_Function` (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.
+
+- `unsafe_undefined` (default: `false`) — substitute `void 0` if there is a
+  variable named `undefined` in scope (variable name will be mangled, typically
+  reduced to a single character)
+
+- `unused` (default: `true`) — drop unreferenced functions and variables (simple
+  direct variable assignments do not count as references unless set to `"keep_assign"`)
+
+- `varify` (default: `true`) — convert block-scoped declaractions into `var`
+  whenever safe to do so
+
+- `yields` (default: `true`) — apply optimizations to `yield` expressions
 
 ## Mangle options
 
-- `reserved` (default `[]`). Pass an array of identifiers that should be
+- `eval` (default: `false`) — Pass `true` to mangle names visible in scopes
+  where `eval` or `with` are used.
+
+- `reserved` (default: `[]`) — Pass an array of identifiers that should be
   excluded from mangling. Example: `["foo", "bar"]`.
 
-- `toplevel` (default `false`). Pass `true` to mangle names declared in the
+- `toplevel` (default: `false`) — Pass `true` to mangle names declared in the
   top level scope.
 
-- `keep_fnames` (default `false`).  Pass `true` to not mangle function names.
-  Useful for code relying on `Function.prototype.name`. See also: the `keep_fnames`
-  [compress option](#compress-options).
-
-- `eval` (default `false`). Pass `true` to mangle names visible in scopes
-  where `eval` or `with` are used.
-
 Examples:
 
 ```javascript
@@ -717,69 +863,101 @@ 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
+- `builtins` (default: `false`) — Use `true` to allow the mangling of builtin
   DOM properties. Not recommended to override this setting.
 
+- `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.
+
+- `keep_quoted` (default: `false`) — Only mangle unquoted property names.
+
+- `regex` (default: `null`) — Pass a RegExp literal to only mangle property
+  names matching the regular expression.
+
+- `reserved` (default: `[]`) — Do not mangle property names listed in the
+  `reserved` array.
+
 ## Output options
 
 The code generator tries to output shortest code possible by default.  In
 case you want beautified output, pass `--beautify` (`-b`).  Optionally you
 can pass additional arguments that control the code output:
 
-- `ascii_only` (default `false`) -- escape Unicode characters in strings and
+- `annotations` (default: `false`) — pass `true` to retain comment annotations
+  `/*@__PURE__*/` or `/*#__PURE__*/`, otherwise they will be discarded even if
+  `comments` is set.
+
+- `ascii_only` (default: `false`) — escape Unicode characters in strings and
   regexps (affects directives with non-ascii characters becoming invalid)
-- `beautify` (default `true`) -- whether to actually beautify the output.
+
+- `beautify` (default: `true`) — whether to actually beautify the output.
   Passing `-b` will set this to true, but you might need to pass `-b` even
   when you want to generate minified code, in order to specify additional
   arguments, so you can use `-b beautify=false` to override it.
-- `bracketize` (default `false`) -- always insert brackets in `if`, `for`,
+
+- `braces` (default: `false`) — always insert braces in `if`, `for`,
   `do`, `while` or `with` statements, even if their body is a single
   statement.
-- `comments` (default `false`) -- pass `true` or `"all"` to preserve all
-  comments, `"some"` to preserve some comments, a regular expression string
-  (e.g. `/^!/`) or a function.
-- `indent_level` (default 4)
-- `indent_start` (default 0) -- prefix all lines by that many spaces
-- `inline_script` (default `false`) -- escape the slash in occurrences of
-  `</script` in strings
-- `keep_quoted_props` (default `false`) -- when turned on, prevents stripping
+
+- `comments` (default: `false`) — pass `true` or `"all"` to preserve all
+  comments, `"some"` to preserve multi-line comments that contain `@cc_on`,
+  `@license`, or `@preserve` (case-insensitive), a regular expression string
+  (e.g. `/^!/`), or a function which returns `boolean`, e.g.
+  ```javascript
+  function(node, comment) {
+      return comment.value.indexOf("@type " + node.TYPE) >= 0;
+  }
+  ```
+
+- `galio` (default: `false`) — enable workarounds for ANT Galio bugs
+
+- `indent_level` (default: `4`)
+
+- `indent_start` (default: `0`) — prefix all lines by that many spaces
+
+- `inline_script` (default: `true`) — escape HTML comments and the slash in
+  occurrences of `</script>` in strings
+
+- `keep_quoted_props` (default: `false`) — when turned on, prevents stripping
   quotes from property names in object literals.
-- `max_line_len` (default `false`) -- maximum line length (for uglified code)
-- `preamble` (default `null`) -- when passed it must be a string and
+
+- `max_line_len` (default: `false`) — maximum line length (for uglified code)
+
+- `preamble` (default: `null`) — when passed it must be a string and
   it will be prepended to the output literally.  The source map will
   adjust for this text.  Can be used to insert a comment containing
   licensing information, for example.
-- `preserve_line` (default `false`) -- pass `true` to preserve lines, but it
-  only works if `beautify` is set to `false`.
-- `quote_keys` (default `false`) -- pass `true` to quote all keys in literal
+
+- `preserve_line` (default: `false`) — pass `true` to retain line numbering on
+  a best effort basis.
+
+- `quote_keys` (default: `false`) — pass `true` to quote all keys in literal
   objects
-- `quote_style` (default `0`) -- preferred quote style for strings (affects
+
+- `quote_style` (default: `0`) — preferred quote style for strings (affects
   quoted property names and directives as well):
-  - `0` -- prefers double quotes, switches to single quotes when there are
-    more double quotes in the string itself.
-  - `1` -- always use single quotes
-  - `2` -- always use double quotes
-  - `3` -- always use the original quotes
-- `semicolons` (default `true`) -- separate statements with semicolons.  If
+  - `0` — prefers double quotes, switches to single quotes when there are
+    more double quotes in the string itself. `0` is best for gzip size.
+  - `1` — always use single quotes
+  - `2` — always use double quotes
+  - `3` — always use the original quotes
+
+- `semicolons` (default: `true`) — separate statements with semicolons.  If
   you pass `false` then whenever possible we will use a newline instead of a
   semicolon, leading to more readable output of uglified code (size before
   gzip could be smaller; size after gzip insignificantly larger).
-- `shebang` (default `true`) -- preserve shebang `#!` in preamble (bash scripts)
-- `width` (default 80) -- only takes effect when beautification is on, this
+
+- `shebang` (default: `true`) — preserve shebang `#!` in preamble (bash scripts)
+
+- `width` (default: `80`) — only takes effect when beautification is on, this
   specifies an (orientative) line width that the beautifier will try to
   obey.  It refers to the width of the line text (excluding indentation).
   It doesn't work very well currently, but it does make the code generated
   by UglifyJS more readable.
-- `wrap_iife` (default `false`) -- pass `true` to wrap immediately invoked
+
+- `wrap_iife` (default: `false`) — pass `true` to wrap immediately invoked
   function expressions. See
-  [#640](https://github.com/mishoo/UglifyJS2/issues/640) for more details.
+  [#640](https://github.com/mishoo/UglifyJS/issues/640) for more details.
 
 # Miscellaneous
 
@@ -822,10 +1000,6 @@ 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)
 
 ### Conditional compilation
 
@@ -942,8 +1116,9 @@ var result = UglifyJS.minify(ast, {
 ### Working with Uglify AST
 
 Transversal and transformation of the native AST can be performed through
-[`TreeWalker`](http://lisperator.net/uglifyjs/walk) and
-[`TreeTransformer`](http://lisperator.net/uglifyjs/transform) respectively.
+[`TreeWalker`](https://github.com/mishoo/UglifyJS/blob/master/lib/ast.js) and
+[`TreeTransformer`](https://github.com/mishoo/UglifyJS/blob/master/lib/transform.js)
+respectively.
 
 ### ESTree / SpiderMonkey AST
 
@@ -975,3 +1150,180 @@ 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 5 times.
+
+| d3.js | minify size | gzip size | minify time (seconds) |
+| --- | ---: | ---: | ---: |
+| original | 511,371 | 119,932 | - |
+| uglify-js@3.13.0 mangle=false, compress=false | 363,988 | 95,695 | 0.56 |
+| uglify-js@3.13.0 mangle=true, compress=false | 253,305 | 81,281 | 0.99 |
+| uglify-js@3.13.0 mangle=true, compress=true | 244,436 | 79,854 | 5.30 |
+
+To enable fast minify mode from the CLI use:
+```
+uglifyjs file.js -m
+```
+To enable fast minify mode with the API use:
+```javascript
+UglifyJS.minify(code, { compress: false, mangle: true });
+```
+
+### Source maps and debugging
+
+Various `compress` transforms that simplify, rearrange, inline and remove code
+are known to have an adverse effect on debugging with source maps. This is
+expected as code is optimized and mappings are often simply not possible as
+some code no longer exists. For highest fidelity in source map debugging
+disable the Uglify `compress` option and just use `mangle`.
+
+### Compiler assumptions
+
+To allow for better optimizations, the compiler makes various assumptions:
+
+- The code does not rely on preserving its runtime performance characteristics.
+  Typically uglified code will run faster due to less instructions and easier
+  inlining, but may be slower on rare occasions for a specific platform, e.g.
+  see [`reduce_funcs`](#compress-options).
+- `.toString()` and `.valueOf()` don't have side effects, and for built-in
+  objects they have not been overridden.
+- `undefined`, `NaN` and `Infinity` have not been externally redefined.
+- `arguments.callee`, `arguments.caller` and `Function.prototype.caller` are not used.
+- The code doesn't expect the contents of `Function.prototype.toString()` or
+  `Error.prototype.stack` to be anything in particular.
+- Getting and setting properties on a plain object does not cause other side effects
+  (using `.watch()` or `Proxy`).
+- Object properties can be added, removed and modified (not prevented with
+  `Object.defineProperty()`, `Object.defineProperties()`, `Object.freeze()`,
+  `Object.preventExtensions()` or `Object.seal()`).
+- Earlier versions of JavaScript will throw `SyntaxError` with the following:
+  ```javascript
+  ({
+      p: 42,
+      get p() {},
+  });
+  // SyntaxError: Object literal may not have data and accessor property with
+  //              the same name
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Iteration order of keys over an object which contains spread syntax in later
+  versions of Chrome and Node.js may be altered.
+- When `toplevel` is enabled, UglifyJS effectively assumes input code is wrapped
+  within `function(){ ... }`, thus forbids aliasing of declared global variables:
+  ```javascript
+  A = "FAIL";
+  var B = "FAIL";
+  // can be `global`, `self`, `window` etc.
+  var top = function() {
+      return this;
+  }();
+  // "PASS"
+  top.A = "PASS";
+  console.log(A);
+  // "FAIL" after compress and/or mangle
+  top.B = "PASS";
+  console.log(B);
+  ```
+- Use of `arguments` alongside destructuring as function parameters, e.g.
+  `function({}, arguments) {}` will result in `SyntaxError` in earlier versions
+  of Chrome and Node.js - UglifyJS may modify the input which in turn may
+  suppress those errors.
+- Earlier versions of Chrome and Node.js will throw `ReferenceError` with the
+  following:
+  ```javascript
+  var a;
+  try {
+      throw 42;
+  } catch ({
+      [a]: b,
+      // ReferenceError: a is not defined
+  }) {
+      let a;
+  }
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Later versions of JavaScript will throw `SyntaxError` with the following:
+  ```javascript
+  a => {
+      let a;
+  };
+  // SyntaxError: Identifier 'a' has already been declared
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Later versions of JavaScript will throw `SyntaxError` with the following:
+  ```javascript
+  try {
+      // ...
+  } catch ({ message: a }) {
+      var a;
+  }
+  // SyntaxError: Identifier 'a' has already been declared
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Some versions of Chrome and Node.js will throw `ReferenceError` with the
+  following:
+  ```javascript
+  console.log(((a, b = function() {
+      return a;
+      // ReferenceError: a is not defined
+  }()) => b)());
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Some arithmetic operations with `BigInt` may throw `TypeError`:
+  ```javascript
+  1n + 1;
+  // TypeError: can't convert BigInt to number
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Some versions of JavaScript will throw `SyntaxError` with the
+  following:
+  ```javascript
+  console.log(String.raw`\uFo`);
+  // SyntaxError: Invalid Unicode escape sequence
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Some versions of JavaScript will throw `SyntaxError` with the
+  following:
+  ```javascript
+  try {} catch (e) {
+      for (var e of []);
+  }
+  // SyntaxError: Identifier 'e' has already been declared
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Some versions of Chrome and Node.js will give incorrect results with the
+  following:
+  ```javascript
+  console.log({
+      ...{
+          set 42(v) {},
+          42: "PASS",
+      },
+  });
+  // Expected: { '42': 'PASS' }
+  // Actual:   { '42': undefined }
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Later versions of JavaScript will throw `SyntaxError` with the following:
+  ```javascript
+  var await;
+  async function f() {
+      class A {
+          static p = await;
+      }
+  }
+  // SyntaxError: Unexpected reserved word
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Later versions of JavaScript will throw `SyntaxError` with the following:
+  ```javascript
+  var async;
+  for (async of []);
+  // SyntaxError: The left-hand side of a for-of loop may not be 'async'.
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.

appveyor.yml

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

bin/uglifyjs

@@ -3,179 +3,297 @@
 
 "use strict";
 
-// workaround for tty output truncation upon process.exit()
-[process.stdout, process.stderr].forEach(function(stream){
-    if (stream._handle && stream._handle.setBlocking)
-        stream._handle.setBlocking(true);
-});
+require("../tools/tty");
 
 var fs = require("fs");
 var info = require("../package.json");
 var path = require("path");
-var program = require("commander");
 var UglifyJS = require("../tools/node");
 
-var skip_keys = [ "cname", "enclosed", "parent_scope", "scope", "thedef", "uses_eval", "uses_with" ];
+var skip_keys = [ "cname", "fixed", "inlined", "parent_scope", "scope", "uses_eval", "uses_with" ];
 var files = {};
-var options = {
-    compress: false,
-    mangle: false
+var options = {};
+var short_forms = {
+    b: "beautify",
+    c: "compress",
+    d: "define",
+    e: "enclose",
+    h: "help",
+    m: "mangle",
+    o: "output",
+    O: "output-opts",
+    p: "parse",
+    v: "version",
+    V: "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:");
-        var defs = options[option];
-        var padding = "";
-        Object.keys(defs).map(function(name) {
-            if (padding.length < name.length) padding = Array(name.length + 1).join(" ");
-            return [ name, JSON.stringify(defs[name]) ];
-        }).forEach(function(tokens) {
-            text.push("  " + tokens[0] + padding.slice(tokens[0].length - 2) + tokens[1]);
-        });
-        text.push("");
-    }
-    return text.join("\n");
-};
-program.option("-p, --parse <options>", "Specify parser options.", parse_js("parse", true));
-program.option("-c, --compress [options]", "Enable compressor/specify compressor options.", parse_js("compress", true));
-program.option("-m, --mangle [options]", "Mangle names/specify mangler options.", parse_js("mangle", true));
-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.");
-program.option("-d, --define <expr>[=value]", "Global definitions.", parse_js("define"));
-program.option("--ie8", "Support non-standard Internet Explorer 8.");
-program.option("--keep-fnames", "Do not mangle/drop function names. Useful for code relying on Function.prototype.name.");
-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("--toplevel", "Compress and/or mangle variables in toplevel scope.");
-program.option("--verbose", "Print diagnostic messages.");
-program.option("--warn", "Print warning messages.");
-program.option("--wrap <name>", "Embed everything as a function with “exports” corresponding to “name” globally.");
-program.arguments("[files...]").parseArgv(process.argv);
-if (program.configFile) {
-    options = JSON.parse(read_file(program.configFile));
+var args = process.argv.slice(2);
+var paths = [];
+var output, nameCache;
+var specified = {};
+while (args.length) {
+    var arg = args.shift();
+    if (arg[0] != "-") {
+        paths.push(arg);
+    } else if (arg == "--") {
+        paths = paths.concat(args);
+        break;
+    } else if (arg[1] == "-") {
+        process_option(arg.slice(2));
+    } else [].forEach.call(arg.slice(1), function(letter, index, arg) {
+        if (!(letter in short_forms)) fatal("invalid option -" + letter);
+        process_option(short_forms[letter], index + 1 < arg.length);
+    });
 }
-if (!program.output && program.sourceMap && program.sourceMap.url != "inline") {
-    fatal("ERROR: cannot write source map to STDOUT");
-}
-[
-    "compress",
-    "ie8",
-    "mangle",
-    "sourceMap",
-    "toplevel",
-    "wrap"
-].forEach(function(name) {
-    if (name in program) {
-        options[name] = program[name];
-    }
-});
-if (program.beautify) {
-    options.output = typeof program.beautify == "object" ? program.beautify : {};
-    if (!("beautify" in options.output)) {
-        options.output.beautify = true;
-    }
-}
-if (program.comments) {
-    if (typeof options.output != "object") options.output = {};
-    options.output.comments = typeof program.comments == "string" ? program.comments : "some";
-}
-if (program.define) {
-    if (typeof options.compress != "object") options.compress = {};
-    if (typeof options.compress.global_defs != "object") options.compress.global_defs = {};
-    for (var expr in program.define) {
-        options.compress.global_defs[expr] = program.define[expr];
-    }
-}
-if (program.keepFnames) {
-    options.keep_fnames = true;
-}
-if (program.mangleProps) {
-    if (program.mangleProps.domprops) {
-        delete program.mangleProps.domprops;
-    } else {
-        if (typeof program.mangleProps != "object") program.mangleProps = {};
-        if (!Array.isArray(program.mangleProps.reserved)) program.mangleProps.reserved = [];
-        require("../tools/domprops").forEach(function(name) {
-            UglifyJS._push_uniq(program.mangleProps.reserved, name);
-        });
-    }
-    if (typeof options.mangle != "object") options.mangle = {};
-    options.mangle.properties = program.mangleProps;
-}
-var cache;
-if (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");
+
+function process_option(name, no_value) {
+    specified[name] = true;
+    switch (name) {
+      case "help":
+        switch (read_value()) {
+          case "ast":
+            print(UglifyJS.describe_ast());
+            break;
+          case "options":
+            var text = [];
+            var toplevels = [];
+            var padding = "";
+            var defaults = UglifyJS.default_options();
+            for (var name in defaults) {
+                var option = defaults[name];
+                if (option && typeof option == "object") {
+                    text.push("--" + ({
+                        output: "beautify",
+                        sourceMap: "source-map",
+                    }[name] || name) + " options:");
+                    text.push(format_object(option));
+                    text.push("");
+                } else {
+                    if (padding.length < name.length) padding = Array(name.length + 1).join(" ");
+                    toplevels.push([ {
+                        keep_fnames: "keep-fnames",
+                        nameCache: "name-cache",
+                    }[name] || name, option ]);
+                }
+            }
+            toplevels.forEach(function(tokens) {
+                text.push("--" + tokens[0] + padding.slice(tokens[0].length - 2) + tokens[1]);
+            });
+            print(text.join("\n"));
+            break;
+          default:
+            print([
+                "Usage: uglifyjs [files...] [options]",
+                "",
+                "Options:",
+                "  -h, --help                               Print usage information.",
+                "                                           `--help options` for details on available options.",
+                "  -v, -V, --version                        Print version number.",
+                "  -p, --parse <options>                    Specify parser options.",
+                "  -c, --compress [options]                 Enable compressor/specify compressor options.",
+                "  -m, --mangle [options]                   Mangle names/specify mangler options.",
+                "  --mangle-props [options]                 Mangle properties/specify mangler options.",
+                "  -b, --beautify [options]                 Beautify output/specify output options.",
+                "  -O, --output-opts <options>              Output options (beautify disabled).",
+                "  -o, --output <file>                      Output file (default STDOUT).",
+                "  --annotations                            Process and preserve comment annotations.",
+                "  --no-annotations                         Ignore and discard comment annotations.",
+                "  --comments [filter]                      Preserve copyright comments in the output.",
+                "  --config-file <file>                     Read minify() options from JSON file.",
+                "  -d, --define <expr>[=value]              Global definitions.",
+                "  -e, --enclose [arg[,...][:value[,...]]]  Embed everything in a big function, with configurable argument(s) & value(s).",
+                "  --ie8                                    Support non-standard Internet Explorer 8.",
+                "  --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.",
+                "  --rename                                 Force symbol expansion.",
+                "  --no-rename                              Disable symbol expansion.",
+                "  --self                                   Build UglifyJS as a library (implies --wrap UglifyJS)",
+                "  --source-map [options]                   Enable source map/specify source map options.",
+                "  --timings                                Display operations run time on STDERR.",
+                "  --toplevel                               Compress and/or mangle variables in toplevel scope.",
+                "  --validate                               Perform validation during AST manipulations.",
+                "  --verbose                                Print diagnostic messages.",
+                "  --warn                                   Print warning messages.",
+                "  --webkit                                 Support non-standard Safari/Webkit.",
+                "  --wrap <name>                            Embed everything as a function with “exports” corresponding to “name” globally.",
+                "",
+                "(internal debug use only)",
+                "  --in-situ                                Warning: replaces original source files with minified output.",
+                "  --reduce-test                            Reduce a standalone test case (assumes cloned repository).",
+            ].join("\n"));
         }
+        process.exit();
+      case "version":
+        print(info.name + " " + info.version);
+        process.exit();
+      case "config-file":
+        var config = JSON.parse(read_file(read_value(true)));
+        if (config.mangle && config.mangle.properties && config.mangle.properties.regex) {
+            config.mangle.properties.regex = UglifyJS.parse(config.mangle.properties.regex, {
+                expression: true,
+            }).value;
+        }
+        for (var key in config) if (!(key in options)) options[key] = config[key];
+        break;
+      case "compress":
+      case "mangle":
+        options[name] = parse_js(read_value(), options[name]);
+        break;
+      case "source-map":
+        options.sourceMap = parse_js(read_value(), options.sourceMap);
+        break;
+      case "enclose":
+        options[name] = read_value();
+        break;
+      case "annotations":
+      case "ie8":
+      case "timings":
+      case "toplevel":
+      case "validate":
+      case "webkit":
+        options[name] = true;
+        break;
+      case "no-annotations":
+        options.annotations = false;
+        break;
+      case "keep-fnames":
+        options.keep_fnames = true;
+        break;
+      case "wrap":
+        options[name] = read_value(true);
+        break;
+      case "verbose":
+        options.warnings = "verbose";
+        break;
+      case "warn":
+        if (!options.warnings) options.warnings = true;
+        break;
+      case "beautify":
+        options.output = parse_js(read_value(), options.output);
+        if (!("beautify" in options.output)) options.output.beautify = true;
+        break;
+      case "output-opts":
+        options.output = parse_js(read_value(true), options.output);
+        break;
+      case "comments":
+        if (typeof options.output != "object") options.output = {};
+        options.output.comments = read_value();
+        if (options.output.comments === true) options.output.comments = "some";
+        break;
+      case "define":
+        if (typeof options.compress != "object") options.compress = {};
+        options.compress.global_defs = parse_js(read_value(true), options.compress.global_defs, "define");
+        break;
+      case "mangle-props":
+        if (typeof options.mangle != "object") options.mangle = {};
+        options.mangle.properties = parse_js(read_value(), options.mangle.properties);
+        break;
+      case "name-cache":
+        nameCache = read_value(true);
+        options.nameCache = JSON.parse(read_file(nameCache, "{}"));
+        break;
+      case "output":
+        output = read_value(true);
+        break;
+      case "parse":
+        options.parse = parse_js(read_value(true), options.parse);
+        break;
+      case "rename":
+        options.rename = true;
+        break;
+      case "no-rename":
+        options.rename = false;
+        break;
+      case "in-situ":
+      case "reduce-test":
+      case "self":
+        break;
+      default:
+        fatal("invalid option --" + name);
+    }
+
+    function read_value(required) {
+        if (no_value || !args.length || args[0][0] == "-") {
+            if (required) fatal("missing option argument for --" + name);
+            return true;
+        }
+        return args.shift();
     }
 }
-if (program.output == "ast") {
-    options.output = {
-        ast: true,
-        code: false
-    };
-}
-if (program.parse) {
-    if (!program.parse.acorn && !program.parse.spidermonkey) {
-        options.parse = program.parse;
-    } else if (program.sourceMap && program.sourceMap.content == "inline") {
-        fatal("ERROR: inline source map only works with built-in parser");
+if (!output && options.sourceMap && options.sourceMap.url != "inline") fatal("cannot write source map to STDOUT");
+if (specified["beautify"] && specified["output-opts"]) fatal("--beautify cannot be used with --output-opts");
+[ "compress", "mangle" ].forEach(function(name) {
+    if (!(name in options)) options[name] = false;
+});
+if (options.mangle && options.mangle.properties) {
+    if (options.mangle.properties.domprops) {
+        delete options.mangle.properties.domprops;
+    } else {
+        if (typeof options.mangle.properties != "object") options.mangle.properties = {};
+        if (!Array.isArray(options.mangle.properties.reserved)) options.mangle.properties.reserved = [];
+        require("../tools/domprops").forEach(function(name) {
+            UglifyJS.push_uniq(options.mangle.properties.reserved, name);
+        });
     }
 }
+if (/^ast|spidermonkey$/.test(output)) {
+    if (typeof options.output != "object") options.output = {};
+    options.output.ast = true;
+    options.output.code = false;
+}
+if (options.parse && (options.parse.acorn || options.parse.spidermonkey)
+    && options.sourceMap && options.sourceMap.content == "inline") {
+    fatal("inline source map only works with built-in parser");
+}
+if (options.warnings) {
+    UglifyJS.AST_Node.log_function(print_error, options.warnings == "verbose");
+    delete options.warnings;
+}
 var convert_path = function(name) {
     return name;
 };
-if (typeof program.sourceMap == "object" && "base" in program.sourceMap) {
+if (typeof options.sourceMap == "object" && "base" in options.sourceMap) {
     convert_path = function() {
-        var base = program.sourceMap.base;
+        var base = options.sourceMap.base;
         delete options.sourceMap.base;
         return function(name) {
             return path.relative(base, name);
         };
     }();
 }
-if (program.verbose) {
-    options.warnings = "verbose";
-} else if (program.warn) {
-    options.warnings = true;
-}
-if (program.self) {
-    if (program.args.length) {
-        console.error("WARN: Ignoring input files since --self was passed");
-    }
+if (specified["self"]) {
+    if (paths.length) UglifyJS.AST_Node.warn("Ignoring input files since --self was passed");
     if (!options.wrap) options.wrap = "UglifyJS";
-    simple_glob(UglifyJS.FILES).forEach(function(name) {
+    paths = UglifyJS.FILES;
+}
+if (specified["in-situ"]) {
+    if (output && output != "spidermonkey" || specified["reduce-test"] || specified["self"]) {
+        fatal("incompatible options specified");
+    }
+    paths.forEach(function(name) {
+        print(name);
+        if (/^ast|spidermonkey$/.test(name)) fatal("invalid file name specified");
+        files = {};
         files[convert_path(name)] = read_file(name);
+        output = name;
+        run();
     });
-    run();
-} else if (program.args.length) {
-    simple_glob(program.args).forEach(function(name) {
+} else if (paths.length) {
+    simple_glob(paths).forEach(function(name) {
         files[convert_path(name)] = read_file(name);
     });
     run();
 } else {
+    var timerId = process.stdin.isTTY && process.argv.length < 3 && setTimeout(function() {
+        print_error("Waiting for input... (use `--help` to print usage information)");
+    }, 1500);
     var chunks = [];
     process.stdin.setEncoding("utf8");
-    process.stdin.on("data", function(chunk) {
+    process.stdin.once("data", function() {
+        clearTimeout(timerId);
+    }).on("data", function(chunk) {
         chunks.push(chunk);
     }).on("end", function() {
-        files = [ chunks.join("") ];
+        files = { STDIN: chunks.join("") };
         run();
     });
     process.stdin.resume();
@@ -186,21 +304,54 @@ function convert_ast(fn) {
 }
 
 function run() {
-    UglifyJS.AST_Node.warn_function = function(msg) {
-        console.error("WARN:", msg);
-    };
-    if (program.timings) options.timings = true;
+    var content = options.sourceMap && options.sourceMap.content;
+    if (content && content != "inline") {
+        UglifyJS.AST_Node.info("Using input source map: {content}", {
+            content : content,
+        });
+        options.sourceMap.content = read_file(content, content);
+    }
     try {
-        if (program.parse) {
-            if (program.parse.acorn) {
+        if (options.parse) {
+            if (options.parse.acorn) {
+                var annotations = Object.create(null);
                 files = convert_ast(function(toplevel, name) {
-                    return require("acorn").parse(files[name], {
+                    var content = files[name];
+                    var list = annotations[name] = [];
+                    var prev = -1;
+                    return require("acorn").parse(content, {
+                        allowHashBang: true,
+                        ecmaVersion: "latest",
                         locations: true,
+                        onComment: function(block, text, start, end) {
+                            var match = /[@#]__PURE__/.exec(text);
+                            if (!match) {
+                                if (start != prev) return;
+                                match = [ list[prev] ];
+                            }
+                            while (/\s/.test(content[end])) end++;
+                            list[end] = match[0];
+                            prev = end;
+                        },
+                        preserveParens: true,
                         program: toplevel,
-                        sourceFile: name
+                        sourceFile: name,
+                        sourceType: "module",
                     });
                 });
-            } else if (program.parse.spidermonkey) {
+                files.walk(new UglifyJS.TreeWalker(function(node) {
+                    if (!(node instanceof UglifyJS.AST_Call)) return;
+                    var list = annotations[node.start.file];
+                    var pure = list[node.start.pos];
+                    if (!pure) {
+                        var pos = node.start.parens;
+                        if (pos) for (var i = 0; !pure && i < pos.length; i++) {
+                            pure = list[pos[i]];
+                        }
+                    }
+                    if (pure) node.pure = pure;
+                }));
+            } else if (options.parse.spidermonkey) {
                 files = convert_ast(function(toplevel, name) {
                     var obj = JSON.parse(files[name]);
                     if (!toplevel) return obj;
@@ -212,35 +363,70 @@ function run() {
     } catch (ex) {
         fatal(ex);
     }
-    var result = UglifyJS.minify(files, options);
+    var result;
+    if (specified["reduce-test"]) {
+        // load on demand - assumes cloned repository
+        var reduce_test = require("../test/reduce");
+        if (Object.keys(files).length != 1) fatal("can only test on a single file");
+        result = reduce_test(files[Object.keys(files)[0]], options, {
+            log: print_error,
+            verbose: true,
+        });
+    } else {
+        result = UglifyJS.minify(files, options);
+    }
     if (result.error) {
         var ex = result.error;
         if (ex.name == "SyntaxError") {
-            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];
-            if (!line && !col) {
-                line = lines[ex.line - 2];
-                col = line.length;
-            }
-            if (line) {
-                var limit = 70;
-                if (col > limit) {
-                    line = line.slice(col - limit);
-                    col = limit;
+            print_error("Parse error at " + ex.filename + ":" + ex.line + "," + ex.col);
+            var file = files[ex.filename];
+            if (file) {
+                var col = ex.col;
+                var lines = file.split(/\r?\n/);
+                var line = lines[ex.line - 1];
+                if (!line && !col) {
+                    line = lines[ex.line - 2];
+                    col = line.length;
+                }
+                if (line) {
+                    var limit = 70;
+                    if (col > limit) {
+                        line = line.slice(col - limit);
+                        col = limit;
+                    }
+                    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) {
-            console.error("Supported options:");
-            console.error(ex.defs);
+        } else if (ex.defs) {
+            print_error("Supported options:");
+            print_error(format_object(ex.defs));
         }
         fatal(ex);
-    } else if (program.output == "ast") {
-        console.log(JSON.stringify(result.ast, function(key, value) {
+    } else if (output == "ast") {
+        if (!options.compress && !options.mangle) {
+            var toplevel = result.ast;
+            if (!(toplevel instanceof UglifyJS.AST_Toplevel)) {
+                if (!(toplevel instanceof UglifyJS.AST_Statement)) toplevel = new UglifyJS.AST_SimpleStatement({
+                    body: toplevel,
+                });
+                toplevel = new UglifyJS.AST_Toplevel({
+                    body: [ toplevel ],
+                });
+            }
+            toplevel.figure_out_scope({});
+        }
+        print(JSON.stringify(result.ast, function(key, value) {
+            if (value) switch (key) {
+              case "enclosed":
+                return value.length ? value.map(symdef) : undefined;
+              case "functions":
+              case "globals":
+              case "variables":
+                return value.size() ? value.map(symdef) : undefined;
+              case "thedef":
+                return symdef(value);
+            }
             if (skip_key(key)) return;
             if (value instanceof UglifyJS.AST_Token) return;
             if (value instanceof UglifyJS.Dictionary) return;
@@ -255,36 +441,37 @@ function run() {
             }
             return value;
         }, 2));
-    } else if (program.output == "spidermonkey") {
-        console.log(JSON.stringify(UglifyJS.minify(result.code, {
-            compress: false,
-            mangle: false,
-            output: {
-                ast: true,
-                code: false
+    } else if (output == "spidermonkey") {
+        print(JSON.stringify(result.ast.to_mozilla_ast(), null, 2));
+    } else if (output) {
+        var code;
+        if (result.ast) {
+            var opts = {};
+            for (var name in options.output) {
+                if (!/^ast|code$/.test(name)) opts[name] = options.output[name];
             }
-        }).ast.to_mozilla_ast(), null, 2));
-    } else if (program.output) {
-        fs.writeFileSync(program.output, result.code);
-        if (result.map) {
-            fs.writeFileSync(program.output + ".map", result.map);
+            code = UglifyJS.AST_Node.from_mozilla_ast(result.ast.to_mozilla_ast()).print_to_string(opts);
+        } else {
+            code = result.code;
         }
+        fs.writeFileSync(output, code);
+        if (result.map) fs.writeFileSync(output + ".map", result.map);
     } else {
-        console.log(result.code);
-    }
-    if (program.nameCache) {
-        fs.writeFileSync(program.nameCache, JSON.stringify(cache, function(key, value) {
-            return value instanceof UglifyJS.Dictionary ? value.toObject() : value;
-        }));
+        print(result.code);
     }
+    if (nameCache) fs.writeFileSync(nameCache, JSON.stringify(options.nameCache));
     if (result.timings) for (var phase in result.timings) {
-        console.error("- " + phase + ": " + result.timings[phase].toFixed(3) + "s");
+        print_error("- " + phase + ": " + result.timings[phase].toFixed(3) + "s");
     }
 }
 
 function fatal(message) {
-    if (message instanceof Error) message = message.stack.replace(/^\S*?Error:/, "ERROR:")
-    console.error(message);
+    if (message instanceof Error) {
+        message = message.stack.replace(/^\S*?Error:/, "ERROR:")
+    } else {
+        message = "ERROR: " + message;
+    }
+    print_error(message);
     process.exit(1);
 }
 
@@ -308,7 +495,7 @@ function simple_glob(glob) {
                 .replace(/\?/g, "[^/\\\\]") + "$";
             var mod = process.platform === "win32" ? "i" : "";
             var rx = new RegExp(pattern, mod);
-            var results = entries.filter(function(name) {
+            var results = entries.sort().filter(function(name) {
                 return rx.test(name);
             }).map(function(name) {
                 return path.join(dir, name);
@@ -328,78 +515,75 @@ function read_file(path, default_value) {
     }
 }
 
-function parse_js(flag, constants) {
-    return function(value, options) {
-        options = options || {};
-        try {
-            UglifyJS.minify(value, {
-                parse: {
-                    expression: true
-                },
-                compress: false,
-                mangle: false,
-                output: {
-                    ast: true,
-                    code: false
+function parse_js(value, options, flag) {
+    if (!options || typeof options != "object") options = {};
+    if (typeof value == "string") try {
+        UglifyJS.parse(value, {
+            expression: true
+        }).walk(new UglifyJS.TreeWalker(function(node) {
+            if (node instanceof UglifyJS.AST_Assign) {
+                var name = node.left.print_to_string();
+                var value = node.right;
+                if (flag) {
+                    options[name] = value;
+                } else if (value instanceof UglifyJS.AST_Array) {
+                    options[name] = value.elements.map(to_string);
+                } else {
+                    options[name] = to_string(value);
                 }
-            }).ast.walk(new UglifyJS.TreeWalker(function(node) {
-                if (node instanceof UglifyJS.AST_Assign) {
-                    var name = node.left.print_to_string();
-                    var value = node.right;
-                    if (!constants) {
-                        options[name] = value;
-                    } else if (value instanceof UglifyJS.AST_Array) {
-                        options[name] = value.elements.map(to_string);
-                    } else {
-                        options[name] = to_string(value);
-                    }
-                    return true;
-                }
-                if (node instanceof UglifyJS.AST_Symbol || node instanceof UglifyJS.AST_PropAccess) {
-                    var name = node.print_to_string();
-                    options[name] = true;
-                    return true;
-                }
-                if (!(node instanceof UglifyJS.AST_Sequence)) throw node;
+                return true;
+            }
+            if (node instanceof UglifyJS.AST_Symbol || node instanceof UglifyJS.AST_PropAccess) {
+                var name = node.print_to_string();
+                options[name] = true;
+                return true;
+            }
+            if (!(node instanceof UglifyJS.AST_Sequence)) throw node;
 
-                function to_string(value) {
-                    return value instanceof UglifyJS.AST_Constant ? value.getValue() : value.print_to_string({
-                        quote_keys: true
-                    });
-                }
-            }));
-        } catch(ex) {
+            function to_string(value) {
+                return value instanceof UglifyJS.AST_Constant ? value.value : value.print_to_string({
+                    quote_keys: true
+                });
+            }
+        }));
+    } catch (ex) {
+        if (flag) {
+            fatal("cannot parse arguments for '" + flag + "': " + value);
+        } else {
             options[value] = null;
         }
-        return options;
     }
-}
-
-function parse_source_map() {
-    var parse = parse_js("sourceMap", true);
-    return function(value, options) {
-        var hasContent = options && options.sourceMap && "content" in options.sourceMap;
-        var settings = parse(value, options);
-        if (!hasContent && settings.content && settings.content != "inline") {
-            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];
+    return options;
 }
 
 function skip_key(key) {
     return skip_keys.indexOf(key) >= 0;
 }
+
+function symdef(def) {
+    var ret = (1e6 + def.id) + " " + def.name;
+    if (def.mangled_name) ret += " " + def.mangled_name;
+    return ret;
+}
+
+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/minify.js

@@ -1,81 +1,149 @@
 "use strict";
 
-var to_ascii = typeof atob == "undefined" ? function(b64) {
-    return new Buffer(b64, "base64").toString();
-} : atob;
-var to_base64 = typeof btoa == "undefined" ? function(str) {
-    return new Buffer(str).toString("base64");
-} : btoa;
+var to_ascii, to_base64;
+if (typeof Buffer == "undefined") {
+    to_ascii = atob;
+    to_base64 = btoa;
+} else if (typeof Buffer.alloc == "undefined") {
+    to_ascii = function(b64) {
+        return new Buffer(b64, "base64").toString();
+    };
+    to_base64 = function(str) {
+        return new Buffer(str).toString("base64");
+    };
+} else {
+    to_ascii = function(b64) {
+        return Buffer.from(b64, "base64").toString();
+    };
+    to_base64 = function(str) {
+        return Buffer.from(str).toString("base64");
+    };
+}
 
-function read_source_map(code) {
-    var match = /\n\/\/# sourceMappingURL=data:application\/json(;.*?)?;base64,(.*)/.exec(code);
-    if (!match) {
-        AST_Node.warn("inline source map not found");
-        return null;
+function read_source_map(name, toplevel) {
+    var comments = toplevel.end.comments_after;
+    for (var i = comments.length; --i >= 0;) {
+        var comment = comments[i];
+        if (comment.type != "comment1") break;
+        var match = /^# ([^\s=]+)=(\S+)\s*$/.exec(comment.value);
+        if (!match) break;
+        if (match[1] == "sourceMappingURL") {
+            match = /^data:application\/json(;.*?)?;base64,(\S+)$/.exec(match[2]);
+            if (!match) break;
+            return to_ascii(match[2]);
+        }
+    }
+    AST_Node.warn("inline source map not found: {name}", {
+        name: name,
+    });
+}
+
+function parse_source_map(content) {
+    try {
+        return JSON.parse(content);
+    } catch (ex) {
+        throw new Error("invalid input source map: " + content);
     }
-    return to_ascii(match[2]);
 }
 
 function set_shorthand(name, options, keys) {
-    if (options[name]) {
-        keys.forEach(function(key) {
-            if (options[key]) {
-                if (typeof options[key] != "object") options[key] = {};
-                if (!(name in options[key])) options[key][name] = options[name];
-            }
-        });
+    keys.forEach(function(key) {
+        if (options[key]) {
+            if (typeof options[key] != "object") options[key] = {};
+            if (!(name in options[key])) options[key][name] = options[name];
+        }
+    });
+}
+
+function init_cache(cache) {
+    if (!cache) return;
+    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 {
+        props: cache.props.toObject()
+    };
+}
+
 function minify(files, options) {
-    var warn_function = AST_Node.warn_function;
     try {
         options = defaults(options, {
+            annotations: undefined,
             compress: {},
+            enclose: false,
             ie8: false,
             keep_fnames: false,
             mangle: {},
+            nameCache: null,
             output: {},
             parse: {},
+            rename: undefined,
             sourceMap: false,
             timings: false,
             toplevel: false,
+            v8: false,
+            validate: false,
             warnings: false,
+            webkit: 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" ]);
+        if (options.validate) AST_Node.enable_validation();
+        var timings = options.timings && { start: Date.now() };
+        if (options.rename === undefined) options.rename = options.compress && options.mangle;
+        if (options.annotations !== undefined) set_shorthand("annotations", options, [ "compress", "output" ]);
+        if (options.ie8) set_shorthand("ie8", options, [ "compress", "mangle", "output" ]);
+        if (options.keep_fnames) set_shorthand("keep_fnames", options, [ "compress", "mangle" ]);
+        if (options.toplevel) set_shorthand("toplevel", options, [ "compress", "mangle" ]);
+        if (options.v8) set_shorthand("v8", options, [ "mangle", "output" ]);
+        if (options.webkit) set_shorthand("webkit", options, [ "mangle", "output" ]);
+        var quoted_props;
         if (options.mangle) {
             options.mangle = defaults(options.mangle, {
-                cache: null,
+                cache: options.nameCache && (options.nameCache.vars || {}),
                 eval: false,
                 ie8: false,
                 keep_fnames: false,
                 properties: false,
                 reserved: [],
                 toplevel: false,
+                v8: false,
+                webkit: 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, {
                 content: null,
                 filename: null,
                 includeSources: false,
+                names: true,
                 root: null,
                 url: null,
             }, true);
         }
         var warnings = [];
-        if (options.warnings && !AST_Node.warn_function) {
-            AST_Node.warn_function = function(warning) {
-                warnings.push(warning);
-            };
-        }
+        if (options.warnings) AST_Node.log_function(function(warning) {
+            warnings.push(warning);
+        }, options.warnings == "verbose");
         if (timings) timings.parse = Date.now();
         var toplevel;
         if (files instanceof AST_Toplevel) {
@@ -86,84 +154,108 @@ function minify(files, options) {
             }
             options.parse = options.parse || {};
             options.parse.toplevel = null;
-            for (var name in files) {
+            var source_map_content = options.sourceMap && options.sourceMap.content;
+            if (typeof source_map_content == "string" && source_map_content != "inline") {
+                source_map_content = parse_source_map(source_map_content);
+            }
+            if (source_map_content) options.sourceMap.orig = Object.create(null);
+            for (var name in files) if (HOP(files, name)) {
                 options.parse.filename = name;
-                options.parse.toplevel = parse(files[name], options.parse);
-                if (options.sourceMap && options.sourceMap.content == "inline") {
-                    if (Object.keys(files).length > 1)
-                        throw new Error("inline source map only works with singular input");
-                    options.sourceMap.content = read_source_map(files[name]);
+                options.parse.toplevel = toplevel = parse(files[name], options.parse);
+                if (source_map_content == "inline") {
+                    var inlined_content = read_source_map(name, toplevel);
+                    if (inlined_content) {
+                        options.sourceMap.orig[name] = parse_source_map(inlined_content);
+                    }
+                } else if (source_map_content) {
+                    options.sourceMap.orig[name] = source_map_content;
                 }
             }
-            toplevel = options.parse.toplevel;
         }
-        if (options.wrap) {
-            toplevel = toplevel.wrap_commonjs(options.wrap);
+        if (quoted_props) {
+            reserve_quoted_keys(toplevel, quoted_props);
+        }
+        [ "enclose", "wrap" ].forEach(function(action) {
+            var option = options[action];
+            if (!option) return;
+            var orig = toplevel.print_to_string().slice(0, -1);
+            toplevel = toplevel[action](option);
+            files[toplevel.start.file] = toplevel.print_to_string().replace(orig, "");
+        });
+        if (options.validate) toplevel.validate_ast();
+        if (timings) timings.rename = Date.now();
+        if (options.rename) {
+            toplevel.figure_out_scope(options.mangle);
+            toplevel.expand_names(options.mangle);
         }
-        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.compress) {
+            toplevel = new Compressor(options.compress).compress(toplevel);
+            if (options.validate) toplevel.validate_ast();
+        }
+        if (timings) timings.scope = Date.now();
         if (options.mangle) toplevel.figure_out_scope(options.mangle);
         if (timings) timings.mangle = Date.now();
         if (options.mangle) {
-            base54.reset();
             toplevel.compute_char_frequency(options.mangle);
             toplevel.mangle_names(options.mangle);
         }
         if (timings) timings.properties = Date.now();
-        if (options.mangle && options.mangle.properties) {
-            toplevel = mangle_properties(toplevel, options.mangle.properties);
-        }
+        if (options.mangle && options.mangle.properties) mangle_properties(toplevel, options.mangle.properties);
         if (timings) timings.output = Date.now();
         var result = {};
-        if (options.output.ast) {
-            result.ast = toplevel;
-        }
-        if (!HOP(options.output, "code") || options.output.code) {
+        var output = defaults(options.output, {
+            ast: false,
+            code: true,
+        });
+        if (output.ast) result.ast = toplevel;
+        if (output.code) {
             if (options.sourceMap) {
-                if (typeof options.sourceMap.content == "string") {
-                    options.sourceMap.content = JSON.parse(options.sourceMap.content);
-                }
-                options.output.source_map = SourceMap({
-                    file: options.sourceMap.filename,
-                    orig: options.sourceMap.content,
-                    root: options.sourceMap.root
-                });
+                output.source_map = SourceMap(options.sourceMap);
                 if (options.sourceMap.includeSources) {
                     if (files instanceof AST_Toplevel) {
                         throw new Error("original source content unavailable");
-                    } else for (var name in files) {
-                        options.output.source_map.get().setSourceContent(name, files[name]);
+                    } else for (var name in files) if (HOP(files, name)) {
+                        output.source_map.setSourceContent(name, files[name]);
                     }
                 }
             }
-            delete options.output.ast;
-            delete options.output.code;
-            var stream = OutputStream(options.output);
+            delete output.ast;
+            delete output.code;
+            var stream = OutputStream(output);
             toplevel.print(stream);
             result.code = stream.get();
             if (options.sourceMap) {
-                result.map = options.output.source_map.toString();
-                if (options.sourceMap.url == "inline") {
-                    result.code += "\n//# sourceMappingURL=data:application/json;charset=utf-8;base64," + to_base64(result.map);
-                } else if (options.sourceMap.url) {
-                    result.code += "\n//# sourceMappingURL=" + options.sourceMap.url;
+                result.map = output.source_map.toString();
+                var url = options.sourceMap.url;
+                if (url) {
+                    result.code = result.code.replace(/\n\/\/# sourceMappingURL=\S+\s*$/, "");
+                    if (url == "inline") {
+                        result.code += "\n//# sourceMappingURL=data:application/json;charset=utf-8;base64," + to_base64(result.map);
+                    } else {
+                        result.code += "\n//# sourceMappingURL=" + url;
+                    }
                 }
             }
         }
+        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),
+                parse: 1e-3 * (timings.rename - timings.parse),
+                rename: 1e-3 * (timings.compress - timings.rename),
+                compress: 1e-3 * (timings.scope - timings.compress),
+                scope: 1e-3 * (timings.mangle - timings.scope),
                 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;
@@ -172,6 +264,7 @@ function minify(files, options) {
     } catch (ex) {
         return { error: ex };
     } finally {
-        AST_Node.warn_function = warn_function;
+        AST_Node.log_function();
+        AST_Node.disable_validation();
     }
 }

lib/propmangle.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -43,7 +43,8 @@
 
 "use strict";
 
-function find_builtins(reserved) {
+var builtins = function() {
+    var names = [];
     // NaN will be included due to Number.NaN
     [
         "null",
@@ -53,211 +54,206 @@ function find_builtins(reserved) {
         "-Infinity",
         "undefined",
     ].forEach(add);
-    [ Object, Array, Function, Number,
-      String, Boolean, Error, Math,
-      Date, RegExp
-    ].forEach(function(ctor){
+    [
+        Array,
+        Boolean,
+        Date,
+        Error,
+        Function,
+        Math,
+        Number,
+        Object,
+        RegExp,
+        String,
+    ].forEach(function(ctor) {
         Object.getOwnPropertyNames(ctor).map(add);
         if (ctor.prototype) {
+            Object.getOwnPropertyNames(new ctor()).map(add);
             Object.getOwnPropertyNames(ctor.prototype).map(add);
         }
     });
+    return makePredicate(names);
+
+    function add(name) {
+        names.push(name);
+    }
+}();
+
+function reserve_quoted_keys(ast, reserved) {
+    ast.walk(new TreeWalker(function(node) {
+        if (node instanceof AST_ClassProperty) {
+            if (node.start && node.start.quote) add(node.key);
+        } else if (node instanceof AST_ObjectProperty) {
+            if (node.start && node.start.quote) add(node.key);
+        } else if (node instanceof AST_Sub) {
+            addStrings(node.property, add);
+        }
+    }));
+
     function add(name) {
         push_uniq(reserved, name);
     }
 }
 
+function addStrings(node, add) {
+    if (node instanceof AST_Conditional) {
+        addStrings(node.consequent, add);
+        addStrings(node.alternative, add);
+    } else if (node instanceof AST_Sequence) {
+        addStrings(node.tail_node(), add);
+    } else if (node instanceof AST_String) {
+        add(node.value);
+    }
+}
+
 function mangle_properties(ast, options) {
     options = defaults(options, {
         builtins: false,
         cache: null,
         debug: false,
         keep_quoted: false,
-        only_cache: false,
         regex: null,
         reserved: null,
+    }, true);
+
+    var reserved = Object.create(options.builtins ? null : builtins);
+    if (Array.isArray(options.reserved)) options.reserved.forEach(function(name) {
+        reserved[name] = true;
     });
 
-    var reserved = options.reserved || [];
-    if (!options.builtins) find_builtins(reserved);
-
-    var cache = options.cache;
-    if (cache == null) {
-        cache = {
-            cname: -1,
-            props: new Dictionary()
-        };
+    var cname = -1;
+    var cache;
+    if (options.cache) {
+        cache = options.cache.props;
+        cache.each(function(name) {
+            reserved[name] = true;
+        });
+    } else {
+        cache = new Dictionary();
     }
 
     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'
     // the same as passing an empty string.
     var debug = options.debug !== false;
-    var debug_name_suffix;
-    if (debug) {
-        debug_name_suffix = (options.debug === true ? "" : options.debug);
-    }
+    var debug_suffix;
+    if (debug) debug_suffix = options.debug === true ? "" : options.debug;
 
-    var names_to_mangle = [];
-    var unmangleable = [];
-    var to_keep = {};
+    var names_to_mangle = Object.create(null);
+    var unmangleable = Object.create(reserved);
 
     // step 1: find candidates to mangle
-    ast.walk(new TreeWalker(function(node){
-        if (node instanceof AST_ObjectKeyVal) {
-            add(node.key, keep_quoted && node.quote);
-        }
-        else if (node instanceof AST_ObjectProperty) {
-            // setter or getter, since KeyVal is handled above
-            add(node.key.name);
-        }
-        else if (node instanceof AST_Dot) {
+    ast.walk(new TreeWalker(function(node) {
+        if (node instanceof AST_Binary) {
+            if (node.operator == "in") addStrings(node.left, add);
+        } else if (node.TYPE == "Call") {
+            var exp = node.expression;
+            if (exp instanceof AST_Dot) switch (exp.property) {
+              case "defineProperty":
+              case "getOwnPropertyDescriptor":
+                if (node.args.length < 2) break;
+                exp = exp.expression;
+                if (!(exp instanceof AST_SymbolRef)) break;
+                if (exp.name != "Object") break;
+                if (!exp.definition().undeclared) break;
+                addStrings(node.args[1], add);
+                break;
+              case "hasOwnProperty":
+                if (node.args.length < 1) break;
+                addStrings(node.args[0], add);
+                break;
+            }
+        } else if (node instanceof AST_ClassProperty) {
+            if (typeof node.key == "string") add(node.key);
+        } else if (node instanceof AST_Dot) {
             add(node.property);
-        }
-        else if (node instanceof AST_Sub) {
-            addStrings(node.property, keep_quoted);
+        } else if (node instanceof AST_ObjectProperty) {
+            if (typeof node.key == "string") add(node.key);
+        } else if (node instanceof AST_Sub) {
+            addStrings(node.property, add);
         }
     }));
 
-    // step 2: transform the tree, renaming properties
-    return ast.transform(new TreeTransformer(function(node){
-        if (node instanceof AST_ObjectKeyVal) {
-            if (!(keep_quoted && node.quote))
-                node.key = mangle(node.key);
-        }
-        else if (node instanceof AST_ObjectProperty) {
-            // setter or getter
-            node.key.name = mangle(node.key.name);
-        }
-        else if (node instanceof AST_Dot) {
+    // step 2: renaming properties
+    ast.walk(new TreeWalker(function(node) {
+        if (node instanceof AST_Binary) {
+            if (node.operator == "in") mangleStrings(node.left);
+        } else if (node.TYPE == "Call") {
+            var exp = node.expression;
+            if (exp instanceof AST_Dot) switch (exp.property) {
+              case "defineProperty":
+              case "getOwnPropertyDescriptor":
+                if (node.args.length < 2) break;
+                exp = exp.expression;
+                if (!(exp instanceof AST_SymbolRef)) break;
+                if (exp.name != "Object") break;
+                if (!exp.definition().undeclared) break;
+                mangleStrings(node.args[1]);
+                break;
+              case "hasOwnProperty":
+                if (node.args.length < 1) break;
+                mangleStrings(node.args[0]);
+                break;
+            }
+        } else if (node instanceof AST_ClassProperty) {
+            if (typeof node.key == "string") node.key = mangle(node.key);
+        } else if (node instanceof AST_Dot) {
             node.property = mangle(node.property);
+        } else if (node instanceof AST_ObjectProperty) {
+            if (typeof node.key == "string") node.key = mangle(node.key);
+        } else if (node instanceof AST_Sub) {
+            if (!options.keep_quoted) mangleStrings(node.property);
         }
-        else if (node instanceof AST_Sub) {
-            if (!keep_quoted)
-                node.property = mangleStrings(node.property);
-        }
-        // else if (node instanceof AST_String) {
-        //     if (should_mangle(node.value)) {
-        //         AST_Node.warn(
-        //             "Found \"{prop}\" property candidate for mangling in an arbitrary string [{file}:{line},{col}]", {
-        //                 file : node.start.file,
-        //                 line : node.start.line,
-        //                 col  : node.start.col,
-        //                 prop : node.value
-        //             }
-        //         );
-        //     }
-        // }
     }));
 
     // only function declarations after this line
 
     function can_mangle(name) {
-        if (unmangleable.indexOf(name) >= 0) return false;
-        if (reserved.indexOf(name) >= 0) return false;
-        if (options.only_cache) {
-            return cache.props.has(name);
-        }
+        if (unmangleable[name]) return false;
         if (/^-?[0-9]+(\.[0-9]+)?(e[+-][0-9]+)?$/.test(name)) return false;
         return true;
     }
 
     function should_mangle(name) {
-        if (keep_quoted && name in to_keep) return false;
+        if (reserved[name]) 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;
+        return cache.has(name) || names_to_mangle[name];
     }
 
-    function add(name, keep) {
-        if (keep) {
-            to_keep[name] = true;
-            return;
-        }
-
-        if (can_mangle(name))
-            push_uniq(names_to_mangle, name);
-
-        if (!should_mangle(name)) {
-            push_uniq(unmangleable, name);
-        }
+    function add(name) {
+        if (can_mangle(name)) names_to_mangle[name] = true;
+        if (!should_mangle(name)) unmangleable[name] = true;
     }
 
     function mangle(name) {
-        if (!should_mangle(name)) {
-            return name;
-        }
-
-        var mangled = cache.props.get(name);
+        if (!should_mangle(name)) return name;
+        var mangled = cache.get(name);
         if (!mangled) {
             if (debug) {
-                // debug mode: use a prefix and suffix to preserve readability, e.g. o.foo -> o._$foo$NNN_.
-                var debug_mangled = "_$" + name + "$" + debug_name_suffix + "_";
-
-                if (can_mangle(debug_mangled) && !(keep_quoted && debug_mangled in to_keep)) {
-                    mangled = debug_mangled;
-                }
+                // debug mode: use a prefix and suffix to preserve readability, e.g. o.foo ---> o._$foo$NNN_.
+                var debug_mangled = "_$" + name + "$" + debug_suffix + "_";
+                if (can_mangle(debug_mangled)) 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) || keep_quoted && mangled in to_keep);
-            }
-
-            cache.props.set(name, mangled);
+            if (!mangled) do {
+                mangled = base54(++cname);
+            } while (!can_mangle(mangled));
+            if (/^#/.test(name)) mangled = "#" + mangled;
+            cache.set(name, mangled);
         }
         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) {
+        if (node instanceof AST_Sequence) {
+            mangleStrings(node.expressions.tail_node());
+        } else if (node instanceof AST_String) {
+            node.value = mangle(node.value);
+        } else if (node instanceof AST_Conditional) {
+            mangleStrings(node.consequent);
+            mangleStrings(node.alternative);
         }
     }
-
-    function mangleStrings(node) {
-        return node.transform(new TreeTransformer(function(node){
-            if (node instanceof AST_Sequence) {
-                var last = node.expressions.length - 1;
-                node.expressions[last] = mangleStrings(node.expressions[last]);
-            }
-            else if (node instanceof AST_String) {
-                node.value = mangle(node.value);
-            }
-            else if (node instanceof AST_Conditional) {
-                node.consequent = mangleStrings(node.consequent);
-                node.alternative = mangleStrings(node.alternative);
-            }
-            return node;
-        }));
-    }
 }

lib/sourcemap.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -43,55 +43,151 @@
 
 "use strict";
 
-// a small wrapper around fitzgen's source-map library
-function SourceMap(options) {
-    options = defaults(options, {
-        file : null,
-        root : null,
-        orig : null,
+var vlq_char = characters("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/");
+var vlq_bits = vlq_char.reduce(function(map, ch, bits) {
+    map[ch] = bits;
+    return map;
+}, Object.create(null));
 
-        orig_line_diff : 0,
-        dest_line_diff : 0,
-    });
-    var generator = new MOZ_SourceMap.SourceMapGenerator({
-        file       : options.file,
-        sourceRoot : options.root
-    });
-    var orig_map = options.orig && new MOZ_SourceMap.SourceMapConsumer(options.orig);
-
-    if (orig_map && Array.isArray(options.orig.sources)) {
-        orig_map._sources.toArray().forEach(function(source) {
-            var sourceContent = orig_map.sourceContentFor(source, true);
-            if (sourceContent) {
-                generator.setSourceContent(source, sourceContent);
-            }
-        });
+function vlq_decode(indices, str) {
+    var value = 0;
+    var shift = 0;
+    for (var i = 0, j = 0; i < str.length; i++) {
+        var bits = vlq_bits[str[i]];
+        value += (bits & 31) << shift;
+        if (bits & 32) {
+            shift += 5;
+        } else {
+            indices[j++] += value & 1 ? 0x80000000 | -(value >> 1) : value >> 1;
+            value = shift = 0;
+        }
     }
+    return j;
+}
+
+function vlq_encode(num) {
+    var result = "";
+    num = Math.abs(num) << 1 | num >>> 31;
+    do {
+        var bits = num & 31;
+        if (num >>>= 5) bits |= 32;
+        result += vlq_char[bits];
+    } while (num);
+    return result;
+}
+
+function create_array_map() {
+    var map = Object.create(null);
+    var array = [];
+    array.index = function(name) {
+        if (!HOP(map, name)) {
+            map[name] = array.length;
+            array.push(name);
+        }
+        return map[name];
+    };
+    return array;
+}
+
+function SourceMap(options) {
+    var sources = create_array_map();
+    var sources_content = options.includeSources && Object.create(null);
+    var names = create_array_map();
+    var mappings = "";
+    if (options.orig) Object.keys(options.orig).forEach(function(name) {
+        var map = options.orig[name];
+        var indices = [ 0, 0, 1, 0, 0 ];
+        options.orig[name] = {
+            names: map.names,
+            mappings: map.mappings.split(/;/).map(function(line) {
+                indices[0] = 0;
+                return line.split(/,/).map(function(segment) {
+                    return indices.slice(0, vlq_decode(indices, segment));
+                });
+            }),
+            sources: map.sources,
+        };
+        if (!sources_content || !map.sourcesContent) return;
+        for (var i = 0; i < map.sources.length; i++) {
+            var content = map.sourcesContent[i];
+            if (content) sources_content[map.sources[i]] = content;
+        }
+    });
+    var prev_source;
+    var generated_line = 1;
+    var generated_column = 0;
+    var source_index = 0;
+    var original_line = 1;
+    var original_column = 0;
+    var name_index = 0;
+    return {
+        add: options.orig ? function(source, gen_line, gen_col, orig_line, orig_col, name) {
+            var map = options.orig[source];
+            if (map) {
+                var segments = map.mappings[orig_line - 1];
+                if (!segments) return;
+                var indices;
+                for (var i = 0; i < segments.length; i++) {
+                    var col = segments[i][0];
+                    if (orig_col >= col) indices = segments[i];
+                    if (orig_col <= col) break;
+                }
+                if (!indices || indices.length < 4) {
+                    source = null;
+                } else {
+                    source = map.sources[indices[1]];
+                    orig_line = indices[2];
+                    orig_col = indices[3];
+                    if (indices.length > 4) name = map.names[indices[4]];
+                }
+            }
+            add(source, gen_line, gen_col, orig_line, orig_col, name);
+        } : add,
+        setSourceContent: sources_content ? function(source, content) {
+            if (!(source in sources_content)) {
+                sources_content[source] = content;
+            }
+        } : noop,
+        toString: function() {
+            return JSON.stringify({
+                version: 3,
+                file: options.filename || undefined,
+                sourceRoot: options.root || undefined,
+                sources: sources,
+                sourcesContent: sources_content ? sources.map(function(source) {
+                    return sources_content[source] || null;
+                }) : undefined,
+                names: names,
+                mappings: mappings,
+            });
+        }
+    };
 
     function add(source, gen_line, gen_col, orig_line, orig_col, name) {
-        if (orig_map) {
-            var info = orig_map.originalPositionFor({
-                line: orig_line,
-                column: orig_col
-            });
-            if (info.source === null) {
-                return;
-            }
-            source = info.source;
-            orig_line = info.line;
-            orig_col = info.column;
-            name = info.name || name;
+        if (prev_source == null && source == null) return;
+        prev_source = source;
+        if (generated_line < gen_line) {
+            generated_column = 0;
+            do {
+                mappings += ";";
+            } while (++generated_line < gen_line);
+        } else if (mappings) {
+            mappings += ",";
         }
-        generator.addMapping({
-            generated : { line: gen_line + options.dest_line_diff, column: gen_col },
-            original  : { line: orig_line + options.orig_line_diff, column: orig_col },
-            source    : source,
-            name      : name
-        });
-    };
-    return {
-        add        : add,
-        get        : function() { return generator },
-        toString   : function() { return JSON.stringify(generator.toJSON()); }
-    };
-};
+        mappings += vlq_encode(gen_col - generated_column);
+        generated_column = gen_col;
+        if (source == null) return;
+        var src_idx = sources.index(source);
+        mappings += vlq_encode(src_idx - source_index);
+        source_index = src_idx;
+        mappings += vlq_encode(orig_line - original_line);
+        original_line = orig_line;
+        mappings += vlq_encode(orig_col - original_column);
+        original_column = orig_col;
+        if (options.names && name != null) {
+            var name_idx = names.index(name);
+            mappings += vlq_encode(name_idx - name_index);
+            name_index = name_idx;
+        }
+    }
+}

lib/transform.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -43,8 +43,6 @@
 
 "use strict";
 
-// Tree transformer helpers.
-
 function TreeTransformer(before, after) {
     TreeWalker.call(this);
     this.before = before;
@@ -52,166 +50,201 @@ function TreeTransformer(before, after) {
 }
 TreeTransformer.prototype = new TreeWalker;
 
-(function(undefined){
-
-    function _(node, descend) {
-        node.DEFMETHOD("transform", function(tw, in_list){
-            var x, y;
-            tw.push(this);
-            if (tw.before) x = tw.before(this, descend, in_list);
-            if (x === undefined) {
-                if (!tw.after) {
-                    x = this;
-                    descend(x, tw);
-                } else {
-                    tw.stack[tw.stack.length - 1] = x = this;
-                    descend(x, tw);
-                    y = tw.after(x, in_list);
-                    if (y !== undefined) x = y;
-                }
-            }
-            tw.pop(this);
-            return x;
-        });
-    };
-
+(function(DEF) {
     function do_list(list, tw) {
-        return MAP(list, function(node){
+        return List(list, function(node) {
             return node.transform(tw, true);
         });
-    };
+    }
 
-    _(AST_Node, noop);
-
-    _(AST_LabeledStatement, function(self, tw){
+    DEF(AST_Node, noop);
+    DEF(AST_LabeledStatement, function(self, tw) {
         self.label = self.label.transform(tw);
         self.body = self.body.transform(tw);
     });
-
-    _(AST_SimpleStatement, function(self, tw){
+    DEF(AST_SimpleStatement, function(self, tw) {
         self.body = self.body.transform(tw);
     });
-
-    _(AST_Block, function(self, tw){
+    DEF(AST_Block, function(self, tw) {
         self.body = do_list(self.body, tw);
     });
-
-    _(AST_DWLoop, function(self, tw){
+    DEF(AST_Do, function(self, tw) {
+        self.body = self.body.transform(tw);
+        self.condition = self.condition.transform(tw);
+    });
+    DEF(AST_While, function(self, tw) {
         self.condition = self.condition.transform(tw);
         self.body = self.body.transform(tw);
     });
-
-    _(AST_For, function(self, tw){
+    DEF(AST_For, function(self, tw) {
         if (self.init) self.init = self.init.transform(tw);
         if (self.condition) self.condition = self.condition.transform(tw);
         if (self.step) self.step = self.step.transform(tw);
         self.body = self.body.transform(tw);
     });
-
-    _(AST_ForIn, function(self, tw){
+    DEF(AST_ForEnumeration, function(self, tw) {
         self.init = self.init.transform(tw);
         self.object = self.object.transform(tw);
         self.body = self.body.transform(tw);
     });
-
-    _(AST_With, function(self, tw){
+    DEF(AST_With, function(self, tw) {
         self.expression = self.expression.transform(tw);
         self.body = self.body.transform(tw);
     });
-
-    _(AST_Exit, function(self, tw){
+    DEF(AST_Exit, function(self, tw) {
         if (self.value) self.value = self.value.transform(tw);
     });
-
-    _(AST_LoopControl, function(self, tw){
+    DEF(AST_LoopControl, function(self, tw) {
         if (self.label) self.label = self.label.transform(tw);
     });
-
-    _(AST_If, function(self, tw){
+    DEF(AST_If, function(self, tw) {
         self.condition = self.condition.transform(tw);
         self.body = self.body.transform(tw);
         if (self.alternative) self.alternative = self.alternative.transform(tw);
     });
-
-    _(AST_Switch, function(self, tw){
+    DEF(AST_Switch, function(self, tw) {
         self.expression = self.expression.transform(tw);
         self.body = do_list(self.body, tw);
     });
-
-    _(AST_Case, function(self, tw){
+    DEF(AST_Case, function(self, tw) {
         self.expression = self.expression.transform(tw);
         self.body = do_list(self.body, tw);
     });
-
-    _(AST_Try, function(self, tw){
+    DEF(AST_Try, function(self, tw) {
         self.body = do_list(self.body, tw);
         if (self.bcatch) self.bcatch = self.bcatch.transform(tw);
         if (self.bfinally) self.bfinally = self.bfinally.transform(tw);
     });
-
-    _(AST_Catch, function(self, tw){
-        self.argname = self.argname.transform(tw);
+    DEF(AST_Catch, function(self, tw) {
+        if (self.argname) self.argname = self.argname.transform(tw);
         self.body = do_list(self.body, tw);
     });
-
-    _(AST_Definitions, function(self, tw){
+    DEF(AST_Definitions, function(self, tw) {
         self.definitions = do_list(self.definitions, tw);
     });
-
-    _(AST_VarDef, function(self, tw){
+    DEF(AST_VarDef, function(self, tw) {
         self.name = self.name.transform(tw);
         if (self.value) self.value = self.value.transform(tw);
     });
-
-    _(AST_Lambda, function(self, tw){
+    DEF(AST_DefaultValue, function(self, tw) {
+        self.name = self.name.transform(tw);
+        self.value = self.value.transform(tw);
+    });
+    DEF(AST_Lambda, function(self, tw) {
         if (self.name) self.name = self.name.transform(tw);
         self.argnames = do_list(self.argnames, tw);
+        if (self.rest) self.rest = self.rest.transform(tw);
         self.body = do_list(self.body, tw);
     });
-
-    _(AST_Call, function(self, tw){
+    function transform_arrow(self, tw) {
+        self.argnames = do_list(self.argnames, tw);
+        if (self.rest) self.rest = self.rest.transform(tw);
+        if (self.value) {
+            self.value = self.value.transform(tw);
+        } else {
+            self.body = do_list(self.body, tw);
+        }
+    }
+    DEF(AST_Arrow, transform_arrow);
+    DEF(AST_AsyncArrow, transform_arrow);
+    DEF(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);
+    });
+    DEF(AST_ClassProperty, function(self, tw) {
+        if (self.key instanceof AST_Node) self.key = self.key.transform(tw);
+        if (self.value) self.value = self.value.transform(tw);
+    });
+    DEF(AST_Call, function(self, tw) {
         self.expression = self.expression.transform(tw);
         self.args = do_list(self.args, tw);
     });
-
-    _(AST_Sequence, function(self, tw){
+    DEF(AST_Sequence, function(self, tw) {
         self.expressions = do_list(self.expressions, tw);
     });
-
-    _(AST_Dot, function(self, tw){
+    DEF(AST_Await, function(self, tw) {
         self.expression = self.expression.transform(tw);
     });
-
-    _(AST_Sub, function(self, tw){
+    DEF(AST_Yield, function(self, tw) {
+        if (self.expression) self.expression = self.expression.transform(tw);
+    });
+    DEF(AST_Dot, function(self, tw) {
+        self.expression = self.expression.transform(tw);
+    });
+    DEF(AST_Sub, function(self, tw) {
         self.expression = self.expression.transform(tw);
         self.property = self.property.transform(tw);
     });
-
-    _(AST_Unary, function(self, tw){
+    DEF(AST_Spread, function(self, tw) {
         self.expression = self.expression.transform(tw);
     });
-
-    _(AST_Binary, function(self, tw){
+    DEF(AST_Unary, function(self, tw) {
+        self.expression = self.expression.transform(tw);
+    });
+    DEF(AST_Binary, function(self, tw) {
         self.left = self.left.transform(tw);
         self.right = self.right.transform(tw);
     });
-
-    _(AST_Conditional, function(self, tw){
+    DEF(AST_Conditional, function(self, tw) {
         self.condition = self.condition.transform(tw);
         self.consequent = self.consequent.transform(tw);
         self.alternative = self.alternative.transform(tw);
     });
-
-    _(AST_Array, function(self, tw){
+    DEF(AST_Array, function(self, tw) {
         self.elements = do_list(self.elements, tw);
     });
-
-    _(AST_Object, function(self, tw){
-        self.properties = do_list(self.properties, tw);
+    DEF(AST_DestructuredArray, function(self, tw) {
+        self.elements = do_list(self.elements, tw);
+        if (self.rest) self.rest = self.rest.transform(tw);
     });
-
-    _(AST_ObjectProperty, function(self, tw){
+    DEF(AST_DestructuredKeyVal, function(self, tw) {
+        if (self.key instanceof AST_Node) self.key = self.key.transform(tw);
         self.value = self.value.transform(tw);
     });
-
-})();
+    DEF(AST_DestructuredObject, function(self, tw) {
+        self.properties = do_list(self.properties, tw);
+        if (self.rest) self.rest = self.rest.transform(tw);
+    });
+    DEF(AST_Object, function(self, tw) {
+        self.properties = do_list(self.properties, tw);
+    });
+    DEF(AST_ObjectProperty, function(self, tw) {
+        if (self.key instanceof AST_Node) self.key = self.key.transform(tw);
+        self.value = self.value.transform(tw);
+    });
+    DEF(AST_ExportDeclaration, function(self, tw) {
+        self.body = self.body.transform(tw);
+    });
+    DEF(AST_ExportDefault, function(self, tw) {
+        self.body = self.body.transform(tw);
+    });
+    DEF(AST_ExportReferences, function(self, tw) {
+        self.properties = do_list(self.properties, tw);
+    });
+    DEF(AST_Import, function(self, tw) {
+        if (self.all) self.all = self.all.transform(tw);
+        if (self.default) self.default = self.default.transform(tw);
+        if (self.properties) self.properties = do_list(self.properties, tw);
+    });
+    DEF(AST_Template, function(self, tw) {
+        if (self.tag) self.tag = self.tag.transform(tw);
+        self.expressions = do_list(self.expressions, tw);
+    });
+})(function(node, descend) {
+    node.DEFMETHOD("transform", function(tw, in_list) {
+        var x, y;
+        tw.push(this);
+        if (tw.before) x = tw.before(this, descend, in_list);
+        if (typeof x === "undefined") {
+            x = this;
+            descend(x, tw);
+            if (tw.after) {
+                y = tw.after(x, in_list);
+                if (typeof y !== "undefined") x = y;
+            }
+        }
+        tw.pop();
+        return x;
+    });
+});

lib/utils.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -43,40 +43,25 @@
 
 "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);
-};
-
 function characters(str) {
     return str.split("");
-};
+}
 
 function member(name, array) {
     return array.indexOf(name) >= 0;
-};
+}
 
 function find_if(func, array) {
-    for (var i = 0, n = array.length; i < n; ++i) {
-        if (func(array[i]))
-            return array[i];
-    }
-};
+    for (var i = array.length; --i >= 0;) if (func(array[i])) return array[i];
+}
 
 function repeat_string(str, i) {
     if (i <= 0) return "";
     if (i == 1) return str;
     var d = repeat_string(str, i >> 1);
     d += d;
-    if (i & 1) d += str;
-    return d;
-};
+    return i & 1 ? d + str : d;
+}
 
 function configure_error_stack(fn) {
     Object.defineProperty(fn.prototype, "stack", {
@@ -85,7 +70,7 @@ function configure_error_stack(fn) {
             err.name = this.name;
             try {
                 throw err;
-            } catch(e) {
+            } catch (e) {
                 return e.stack;
             }
         }
@@ -95,27 +80,21 @@ function configure_error_stack(fn) {
 function DefaultsError(msg, defs) {
     this.message = msg;
     this.defs = defs;
-};
+}
 DefaultsError.prototype = Object.create(Error.prototype);
 DefaultsError.prototype.constructor = DefaultsError;
 DefaultsError.prototype.name = "DefaultsError";
 configure_error_stack(DefaultsError);
 
-DefaultsError.croak = function(msg, defs) {
-    throw new DefaultsError(msg, defs);
-};
-
 function defaults(args, defs, croak) {
-    if (args === true)
-        args = {};
-    var ret = args || {};
-    if (croak) for (var i in ret) if (HOP(ret, i) && !HOP(defs, i))
-        DefaultsError.croak("`" + i + "` is not a supported option", defs);
-    for (var i in defs) if (HOP(defs, i)) {
-        ret[i] = (args && HOP(args, i)) ? args[i] : defs[i];
+    if (croak) for (var i in args) {
+        if (HOP(args, i) && !HOP(defs, i)) throw new DefaultsError("`" + i + "` is not a supported option", defs);
     }
-    return ret;
-};
+    for (var i in args) {
+        if (HOP(args, i)) defs[i] = args[i];
+    }
+    return defs;
+}
 
 function merge(obj, ext) {
     var count = 0;
@@ -124,7 +103,7 @@ function merge(obj, ext) {
         count++;
     }
     return count;
-};
+}
 
 function noop() {}
 function return_false() { return false; }
@@ -132,164 +111,69 @@ function return_true() { return true; }
 function return_this() { return this; }
 function return_null() { return null; }
 
-var MAP = (function(){
-    function MAP(a, f, backwards) {
-        var ret = [], top = [], i;
-        function doit() {
+var List = (function() {
+    function List(a, f) {
+        var ret = [];
+        for (var i = 0; i < a.length; i++) {
             var val = f(a[i], i);
-            var is_last = val instanceof Last;
-            if (is_last) val = val.v;
-            if (val instanceof AtTop) {
-                val = val.v;
-                if (val instanceof Splice) {
-                    top.push.apply(top, backwards ? val.v.slice().reverse() : val.v);
-                } else {
-                    top.push(val);
-                }
-            }
-            else if (val !== skip) {
-                if (val instanceof Splice) {
-                    ret.push.apply(ret, backwards ? val.v.slice().reverse() : val.v);
-                } else {
-                    ret.push(val);
-                }
-            }
-            return is_last;
-        };
-        if (a instanceof Array) {
-            if (backwards) {
-                for (i = a.length; --i >= 0;) if (doit()) break;
-                ret.reverse();
-                top.reverse();
+            if (val === skip) continue;
+            if (val instanceof Splice) {
+                ret.push.apply(ret, val.v);
             } else {
-                for (i = 0; i < a.length; ++i) if (doit()) break;
+                ret.push(val);
             }
         }
-        else {
-            for (i in a) if (HOP(a, i)) if (doit()) break;
-        }
-        return top.concat(ret);
+        return ret;
+    }
+    List.is_op = function(val) {
+        return val === skip || val instanceof Splice;
     };
-    MAP.at_top = function(val) { return new AtTop(val) };
-    MAP.splice = function(val) { return new Splice(val) };
-    MAP.last = function(val) { return new Last(val) };
-    var skip = MAP.skip = {};
-    function AtTop(val) { this.v = val };
-    function Splice(val) { this.v = val };
-    function Last(val) { this.v = val };
-    return MAP;
+    List.splice = function(val) {
+        return new Splice(val);
+    };
+    var skip = List.skip = {};
+    function Splice(val) {
+        this.v = val;
+    }
+    return List;
 })();
 
 function push_uniq(array, el) {
-    if (array.indexOf(el) < 0)
-        array.push(el);
-};
+    if (array.indexOf(el) < 0) return array.push(el);
+}
 
 function string_template(text, props) {
-    return text.replace(/\{(.+?)\}/g, function(str, p){
-        return props && props[p];
+    return text.replace(/\{([^}]+)\}/g, function(str, p) {
+        var value = props[p];
+        return value instanceof AST_Node ? value.print_to_string() : value;
     });
-};
+}
 
 function remove(array, el) {
-    for (var i = array.length; --i >= 0;) {
-        if (array[i] === el) array.splice(i, 1);
-    }
-};
+    var index = array.indexOf(el);
+    if (index >= 0) array.splice(index, 1);
+}
 
-function mergeSort(array, cmp) {
-    if (array.length < 2) return array.slice();
-    function merge(a, b) {
-        var r = [], ai = 0, bi = 0, i = 0;
-        while (ai < a.length && bi < b.length) {
-            cmp(a[ai], b[bi]) <= 0
-                ? r[i++] = a[ai++]
-                : r[i++] = b[bi++];
-        }
-        if (ai < a.length) r.push.apply(r, a.slice(ai));
-        if (bi < b.length) r.push.apply(r, b.slice(bi));
-        return r;
-    };
-    function _ms(a) {
-        if (a.length <= 1)
-            return a;
-        var m = Math.floor(a.length / 2), left = a.slice(0, m), right = a.slice(m);
-        left = _ms(left);
-        right = _ms(right);
-        return merge(left, right);
-    };
-    return _ms(array);
-};
-
-function set_difference(a, b) {
-    return a.filter(function(el){
-        return b.indexOf(el) < 0;
-    });
-};
-
-function set_intersection(a, b) {
-    return a.filter(function(el){
-        return b.indexOf(el) >= 0;
-    });
-};
-
-// this function is taken from Acorn [1], written by Marijn Haverbeke
-// [1] https://github.com/marijnh/acorn
 function makePredicate(words) {
-    if (!(words instanceof Array)) words = words.split(" ");
-    var f = "", cats = [];
-    out: for (var i = 0; i < words.length; ++i) {
-        for (var j = 0; j < cats.length; ++j)
-            if (cats[j][0].length == words[i].length) {
-                cats[j].push(words[i]);
-                continue out;
-            }
-        cats.push([words[i]]);
-    }
-    function quote(word) {
-        return JSON.stringify(word).replace(/[\u2028\u2029]/g, function(s) {
-            switch (s) {
-                case "\u2028": return "\\u2028";
-                case "\u2029": return "\\u2029";
-            }
-            return s;
-        });
-    }
-    function compareTo(arr) {
-        if (arr.length == 1) return f += "return str === " + quote(arr[0]) + ";";
-        f += "switch(str){";
-        for (var i = 0; i < arr.length; ++i) f += "case " + quote(arr[i]) + ":";
-        f += "return true}return false;";
-    }
-    // When there are more than three length categories, an outer
-    // switch first dispatches on the lengths, to save on comparisons.
-    if (cats.length > 3) {
-        cats.sort(function(a, b) {return b.length - a.length;});
-        f += "switch(str.length){";
-        for (var i = 0; i < cats.length; ++i) {
-            var cat = cats[i];
-            f += "case " + cat[0].length + ":";
-            compareTo(cat);
-        }
-        f += "}";
-        // Otherwise, simply generate a flat `switch` statement.
-    } else {
-        compareTo(words);
-    }
-    return new Function("str", f);
-};
+    if (!Array.isArray(words)) words = words.split(" ");
+    var map = Object.create(null);
+    words.forEach(function(word) {
+        map[word] = true;
+    });
+    return map;
+}
 
 function all(array, predicate) {
     for (var i = array.length; --i >= 0;)
-        if (!predicate(array[i]))
+        if (!predicate(array[i], i))
             return false;
     return true;
-};
+}
 
 function Dictionary() {
     this._values = Object.create(null);
     this._size = 0;
-};
+}
 Dictionary.prototype = {
     set: function(key, val) {
         if (!this.has(key)) ++this._size;
@@ -313,6 +197,12 @@ Dictionary.prototype = {
         return this;
     },
     has: function(key) { return ("$" + key) in this._values },
+    all: function(predicate) {
+        for (var i in this._values)
+            if (!predicate(this._values[i], i.substr(1)))
+                return false;
+        return true;
+    },
     each: function(f) {
         for (var i in this._values)
             f(this._values[i], i.substr(1));
@@ -326,6 +216,13 @@ Dictionary.prototype = {
             ret.push(f(this._values[i], i.substr(1)));
         return ret;
     },
+    clone: function() {
+        var ret = new Dictionary();
+        for (var i in this._values)
+            ret._values[i] = this._values[i];
+        ret._size = this._size;
+        return ret;
+    },
     toObject: function() { return this._values }
 };
 Dictionary.fromObject = function(obj) {
@@ -341,22 +238,30 @@ function HOP(obj, prop) {
 // return true if the node at the top of the stack (that means the
 // innermost node in the current output) is lexically the first in
 // a statement.
-function first_in_statement(stack) {
+function first_in_statement(stack, arrow, export_default) {
     var node = stack.parent(-1);
-    for (var i = 0, p; p = stack.parent(i); i++) {
-        if (p instanceof AST_Statement && p.body === node)
+    for (var i = 0, p; p = stack.parent(i++); node = p) {
+        if (is_arrow(p)) {
+            return arrow && p.value === node;
+        } else if (p instanceof AST_Binary) {
+            if (p.left === node) continue;
+        } else if (p.TYPE == "Call") {
+            if (p.expression === node) continue;
+        } else if (p instanceof AST_Conditional) {
+            if (p.condition === node) continue;
+        } else if (p instanceof AST_ExportDefault) {
+            return export_default;
+        } else if (p instanceof AST_PropAccess) {
+            if (p.expression === node) continue;
+        } else if (p instanceof AST_Sequence) {
+            if (p.expressions[0] === node) continue;
+        } else if (p instanceof AST_SimpleStatement) {
             return true;
-        if ((p instanceof AST_Sequence      && p.expressions[0] === node) ||
-            (p instanceof AST_Call          && p.expression === node && !(p instanceof AST_New) ) ||
-            (p instanceof AST_Dot           && p.expression === node ) ||
-            (p instanceof AST_Sub           && p.expression === node ) ||
-            (p instanceof AST_Conditional   && p.condition === node  ) ||
-            (p instanceof AST_Binary        && p.left === node       ) ||
-            (p instanceof AST_UnaryPostfix  && p.expression === node ))
-        {
-            node = p;
-        } else {
-            return false;
+        } else if (p instanceof AST_Template) {
+            if (p.tag === node) continue;
+        } else if (p instanceof AST_UnaryPostfix) {
+            if (p.expression === node) continue;
         }
+        return false;
     }
 }

package.json

@@ -1,23 +1,17 @@
 {
   "name": "uglify-js",
   "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
-  "homepage": "http://lisperator.net/uglifyjs",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.0.15",
+  "version": "3.13.5",
   "engines": {
     "node": ">=0.8.0"
   },
   "maintainers": [
+    "Alex Lam <alexlamsl@gmail.com>",
     "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)"
   ],
-  "repository": {
-    "type": "git",
-    "url": "https://github.com/mishoo/UglifyJS2.git"
-  },
-  "bugs": {
-    "url": "https://github.com/mishoo/UglifyJS2/issues"
-  },
+  "repository": "mishoo/UglifyJS",
   "main": "tools/node.js",
   "bin": {
     "uglifyjs": "bin/uglifyjs"
@@ -28,17 +22,35 @@
     "tools",
     "LICENSE"
   ],
-  "dependencies": {
-    "commander": "~2.9.0",
-    "source-map": "~0.5.1"
-  },
   "devDependencies": {
-    "acorn": "~5.0.3",
-    "mocha": "~2.3.4",
-    "semver": "~5.3.0"
+    "acorn": "~8.2.1",
+    "semver": "~6.3.0"
   },
   "scripts": {
-    "test": "node test/run-tests.js"
+    "test": "node test/compress.js && node test/mocha.js"
   },
-  "keywords": ["uglify", "uglify-js", "minify", "minifier", "es5"]
+  "keywords": [
+    "cli",
+    "compress",
+    "compressor",
+    "ecma",
+    "ecmascript",
+    "es",
+    "es5",
+    "javascript",
+    "js",
+    "jsmin",
+    "min",
+    "minification",
+    "minifier",
+    "minify",
+    "optimize",
+    "optimizer",
+    "pack",
+    "packer",
+    "parse",
+    "parser",
+    "uglifier",
+    "uglify"
+  ]
 }

test/benchmark.js

@@ -4,27 +4,30 @@
 "use strict";
 
 var createHash = require("crypto").createHash;
-var fork = require("child_process").fork;
+var fetch = require("./fetch");
+var spawn = require("child_process").spawn;
+var zlib = require("zlib");
 var args = process.argv.slice(2);
-if (!args.length) {
-    args.push("-mc");
-}
+if (!args.length) args.push("-mc");
+args.unshift("bin/uglifyjs");
 args.push("--timings");
 var urls = [
-    "https://code.jquery.com/jquery-3.2.1.js",
-    "https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.6.4/angular.js",
-    "https://cdnjs.cloudflare.com/ajax/libs/mathjs/3.9.0/math.js",
-    "https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.js",
+    "https://code.jquery.com/jquery-3.4.1.js",
+    "https://code.angularjs.org/1.7.8/angular.js",
+    "https://unpkg.com/mathjs@6.2.3/dist/math.js",
     "https://unpkg.com/react@15.3.2/dist/react.js",
-    "http://builds.emberjs.com/tags/v2.11.0/ember.prod.js",
-    "https://cdn.jsdelivr.net/lodash/4.17.4/lodash.js",
-    "https://cdnjs.cloudflare.com/ajax/libs/d3/4.5.0/d3.js",
+    "https://cdnjs.cloudflare.com/ajax/libs/d3/5.12.0/d3.js",
+    "https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.js",
+    "https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.js",
+    "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.12.2/ember.prod.js",
+    "https://raw.githubusercontent.com/kangax/html-minifier/v4.0.0/dist/htmlminifier.js",
 ];
 var results = {};
 var remaining = 2 * urls.length;
 function done() {
     if (!--remaining) {
         var failures = [];
+        var sum = { input: 0, output: 0, gzip: 0 };
         urls.forEach(function(url) {
             var info = results[url];
             console.log();
@@ -32,10 +35,14 @@ function done() {
             console.log(info.log);
             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);
             }
+            sum.input += info.input;
+            sum.output += info.output;
+            sum.gzip += info.gzip;
         });
         if (failures.length) {
             console.error("Benchmark failed:");
@@ -43,6 +50,13 @@ function done() {
                 console.error(url);
             });
             process.exit(1);
+        } else {
+            console.log();
+            console.log("Subtotal");
+            console.log();
+            console.log("Original:", sum.input, "bytes");
+            console.log("Uglified:", sum.output, "bytes");
+            console.log("GZipped: ", sum.gzip, "bytes");
         }
     }
 }
@@ -50,17 +64,25 @@ urls.forEach(function(url) {
     results[url] = {
         input: 0,
         output: 0,
+        gzip: 0,
         log: ""
     };
-    require(url.slice(0, url.indexOf(":"))).get(url, function(res) {
-        var uglifyjs = fork("bin/uglifyjs", args, { silent: true });
+    fetch(url, function(err, res) {
+        if (err) throw err;
+        var uglifyjs = spawn(process.argv[0], args, { silent: true });
         res.on("data", function(data) {
             results[url].input += data.length;
         }).pipe(uglifyjs.stdin);
+        var sha1 = createHash("sha1");
         uglifyjs.stdout.on("data", function(data) {
             results[url].output += data.length;
-        }).pipe(createHash("sha1")).on("data", function(data) {
-            results[url].sha1 = data.toString("hex");
+        }).pipe(zlib.createGzip({
+            level: zlib.Z_BEST_COMPRESSION
+        })).on("data", function(data) {
+            results[url].gzip += data.length;
+            sha1.update(data);
+        }).on("end", function() {
+            results[url].sha1 = sha1.digest("hex");
             done();
         });
         uglifyjs.stderr.setEncoding("utf8");

test/compress.js

@@ -0,0 +1,461 @@
+"use strict";
+
+require("../tools/tty");
+
+var assert = require("assert");
+var child_process = require("child_process");
+var fs = require("fs");
+var path = require("path");
+var sandbox = require("./sandbox");
+var semver = require("semver");
+var U = require("./node");
+
+var batch = 50;
+var dir = path.resolve(path.dirname(module.filename), "compress");
+if (process.argv.length > 3) {
+    var file = process.argv[2];
+    var start = process.argv[3] | 0;
+    var minify_options = require("./ufuzz/options.json").map(JSON.stringify);
+    var tests = parse_test(path.resolve(dir, file));
+    process.exit(Object.keys(tests).slice(start, start + batch).filter(function(name) {
+        return !test_case(tests[name]);
+    }).length);
+} else {
+    var files = process.argv.length == 3 ? [ process.argv[2] ] : fs.readdirSync(dir).filter(function(name) {
+        return /\.js$/i.test(name);
+    });
+    var failures = 0;
+    var failed_files = Object.create(null);
+    (function next(file, start, length) {
+        if (start < length) {
+            child_process.spawn(process.argv[0], [ process.argv[1], file, start, batch ], {
+                stdio: [ "ignore", 1, 2 ]
+            }).on("exit", function(code) {
+                if (code) {
+                    failures += code;
+                    failed_files[file] = true;
+                }
+                next(file, start + batch, length);
+            });
+        } else if (file = files.shift()) {
+            log("--- {file}", { file: file });
+            start = 0;
+            length = Object.keys(parse_test(path.resolve(dir, file))).length;
+            next(file, start, length);
+        } else if (failures) {
+            console.error();
+            console.error("!!! Failed " + failures + " test case(s).");
+            console.error("!!! " + Object.keys(failed_files).join(", "));
+            process.exit(1);
+        }
+    })();
+}
+
+function evaluate(code) {
+    if (code instanceof U.AST_Node) code = make_code(code, { beautify: true });
+    return new Function("return(" + code + ")")();
+}
+
+function log() {
+    console.log("%s", tmpl.apply(null, arguments));
+}
+
+function make_code(ast, options) {
+    var stream = U.OutputStream(options);
+    ast.print(stream);
+    return stream.get();
+}
+
+function parse_test(file) {
+    var script = fs.readFileSync(file, "utf8");
+    try {
+        var ast = U.parse(script, {
+            filename: file
+        });
+    } catch (e) {
+        console.error("Caught error while parsing tests in " + file);
+        console.error(e);
+        process.exit(1);
+    }
+    var tests = Object.create(null);
+    var tw = new U.TreeWalker(function(node, descend) {
+        if (node instanceof U.AST_LabeledStatement
+            && tw.parent() instanceof U.AST_Toplevel) {
+            var name = node.label.name;
+            if (name in tests) {
+                throw new Error('Duplicated test name "' + name + '" in ' + file);
+            }
+            tests[name] = get_one_test(name, node.body);
+            return true;
+        }
+        if (!(node instanceof U.AST_Toplevel)) croak(node);
+    });
+    ast.walk(tw);
+    return tests;
+
+    function croak(node) {
+        throw new Error(tmpl("Can't understand test file {file} [{line},{col}]\n{code}", {
+            file: file,
+            line: node.start.line,
+            col: node.start.col,
+            code: make_code(node, { beautify: false })
+        }));
+    }
+
+    function read_string(stat) {
+        if (stat.TYPE == "SimpleStatement") {
+            var body = stat.body;
+            switch(body.TYPE) {
+              case "String":
+                return body.value;
+              case "Array":
+                return body.elements.map(function(element) {
+                    if (element.TYPE !== "String")
+                        throw new Error("Should be array of strings");
+                    return element.value;
+                }).join("\n");
+            }
+        }
+        throw new Error("Should be string or array of strings");
+    }
+
+    function get_one_test(name, block) {
+        var test = { name: name, options: {} };
+        var tw = new U.TreeWalker(function(node, descend) {
+            if (node instanceof U.AST_Assign) {
+                if (!(node.left instanceof U.AST_SymbolRef)) {
+                    croak(node);
+                }
+                var name = node.left.name;
+                test[name] = evaluate(node.right);
+                return true;
+            }
+            if (node instanceof U.AST_LabeledStatement) {
+                var label = node.label;
+                assert.ok([
+                    "input",
+                    "expect",
+                    "expect_exact",
+                    "expect_warnings",
+                    "expect_stdout",
+                    "node_version",
+                ].indexOf(label.name) >= 0, tmpl("Unsupported label {name} [{line},{col}]", {
+                    name: label.name,
+                    line: label.start.line,
+                    col: label.start.col
+                }));
+                var stat = node.body;
+                if (label.name == "expect_exact" || label.name == "node_version") {
+                    test[label.name] = read_string(stat);
+                } else if (label.name == "expect_stdout") {
+                    var body = stat.body;
+                    if (body instanceof U.AST_Boolean) {
+                        test[label.name] = body.value;
+                    } else if (body instanceof U.AST_Call) {
+                        var ctor = global[body.expression.name];
+                        assert.ok(ctor === Error || ctor.prototype instanceof Error, tmpl("Unsupported expect_stdout format [{line},{col}]", {
+                            line: label.start.line,
+                            col: label.start.col
+                        }));
+                        test[label.name] = ctor.apply(null, body.args.map(function(node) {
+                            assert.ok(node instanceof U.AST_Constant, tmpl("Unsupported expect_stdout format [{line},{col}]", {
+                                line: label.start.line,
+                                col: label.start.col
+                            }));
+                            return node.value;
+                        }));
+                    } else {
+                        test[label.name] = read_string(stat) + "\n";
+                    }
+                } else {
+                    test[label.name] = stat;
+                }
+                return true;
+            }
+        });
+        block.walk(tw);
+        return test;
+    }
+}
+
+// Try to reminify original input with standard options
+// to see if it matches expect_stdout.
+function reminify(orig_options, input_code, input_formatted, stdout) {
+    for (var i = 0; i < minify_options.length; i++) {
+        var options = JSON.parse(minify_options[i]);
+        if (options.compress) [
+            "keep_fargs",
+            "keep_fnames",
+        ].forEach(function(name) {
+            if (name in orig_options) {
+                options.compress[name] = orig_options[name];
+            }
+        });
+        var options_formatted = JSON.stringify(options, null, 4);
+        options.validate = true;
+        var result = U.minify(input_code, options);
+        if (result.error) {
+            log([
+                "!!! failed input reminify",
+                "---INPUT---",
+                "{input}",
+                "---OPTIONS---",
+                "{options}",
+                "--ERROR---",
+                "{error}",
+                "",
+                "",
+            ].join("\n"), {
+                input: input_formatted,
+                options: options_formatted,
+                error: result.error,
+            });
+            return false;
+        } else {
+            var toplevel = sandbox.has_toplevel(options);
+            var expected = stdout[toplevel ? 1 : 0];
+            var actual = sandbox.run_code(result.code, toplevel);
+            if (typeof expected != "string" && typeof actual != "string" && expected.name == actual.name) {
+                actual = expected;
+            }
+            if (!sandbox.same_stdout(expected, actual)) {
+                log([
+                    "!!! failed running reminified input",
+                    "---INPUT---",
+                    "{input}",
+                    "---OPTIONS---",
+                    "{options}",
+                    "---OUTPUT---",
+                    "{output}",
+                    "---EXPECTED {expected_type}---",
+                    "{expected}",
+                    "---ACTUAL {actual_type}---",
+                    "{actual}",
+                    "",
+                    "",
+                ].join("\n"), {
+                    input: input_formatted,
+                    options: options_formatted,
+                    output: result.code,
+                    expected_type: typeof expected == "string" ? "STDOUT" : "ERROR",
+                    expected: expected,
+                    actual_type: typeof actual == "string" ? "STDOUT" : "ERROR",
+                    actual: actual,
+                });
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
+function test_case(test) {
+    log("    Running test [{name}]", { name: test.name });
+    U.AST_Node.enable_validation();
+    var output_options = test.beautify || {};
+    var expect;
+    if (test.expect) {
+        expect = make_code(to_toplevel(test.expect, test.mangle), output_options);
+    } else {
+        expect = test.expect_exact;
+    }
+    var input = to_toplevel(test.input, test.mangle);
+    var input_code = make_code(input);
+    var input_formatted = make_code(test.input, {
+        annotations: true,
+        beautify: true,
+        comments: "all",
+        keep_quoted_props: true,
+        quote_style: 3,
+    });
+    try {
+        input.validate_ast();
+        U.parse(input_code);
+    } catch (ex) {
+        log([
+            "!!! Cannot parse input",
+            "---INPUT---",
+            "{input}",
+            "--PARSE ERROR--",
+            "{error}",
+            "",
+            "",
+        ].join("\n"), {
+            input: input_formatted,
+            error: ex,
+        });
+        return false;
+    }
+    var warnings_emitted = [];
+    if (test.expect_warnings) {
+        var expected_warnings = make_code(test.expect_warnings, {
+            beautify: false,
+            quote_style: 2, // force double quote to match JSON
+        });
+        U.AST_Node.log_function(function(text) {
+            warnings_emitted.push(text);
+        }, /"INFO: /.test(expected_warnings));
+    }
+    if (test.mangle && test.mangle.properties && test.mangle.properties.keep_quoted) {
+        var quoted_props = test.mangle.properties.reserved;
+        if (!Array.isArray(quoted_props)) quoted_props = [];
+        test.mangle.properties.reserved = quoted_props;
+        U.reserve_quoted_keys(input, quoted_props);
+    }
+    if (test.rename) {
+        input.figure_out_scope(test.mangle);
+        input.expand_names(test.mangle);
+    }
+    var cmp = new U.Compressor(test.options, true);
+    var output = cmp.compress(input);
+    output.figure_out_scope(test.mangle);
+    if (test.mangle) {
+        output.compute_char_frequency(test.mangle);
+        output.mangle_names(test.mangle);
+        if (test.mangle.properties) U.mangle_properties(output, test.mangle.properties);
+    }
+    var output_code = make_code(output, output_options);
+    U.AST_Node.log_function();
+    if (expect != output_code) {
+        log([
+            "!!! failed",
+            "---INPUT---",
+            "{input}",
+            "---OUTPUT---",
+            "{output}",
+            "---EXPECTED---",
+            "{expected}",
+            "",
+            "",
+        ].join("\n"), {
+            input: input_formatted,
+            output: output_code,
+            expected: expect
+        });
+        return false;
+    }
+    // expect == output
+    try {
+        output.validate_ast();
+        U.parse(output_code);
+    } catch (ex) {
+        log([
+            "!!! Test matched expected result but cannot parse output",
+            "---INPUT---",
+            "{input}",
+            "---OUTPUT---",
+            "{output}",
+            "--REPARSE ERROR--",
+            "{error}",
+            "",
+            "",
+        ].join("\n"), {
+            input: input_formatted,
+            output: output_code,
+            error: ex,
+        });
+        return false;
+    }
+    if (test.expect_warnings) {
+        warnings_emitted = warnings_emitted.map(function(input) {
+            return input.split(process.cwd() + path.sep).join("").split(path.sep).join("/");
+        });
+        var actual_warnings = JSON.stringify(warnings_emitted);
+        if (expected_warnings != actual_warnings) {
+            log([
+                "!!! failed",
+                "---INPUT---",
+                "{input}",
+                "---EXPECTED WARNINGS---",
+                "{expected_warnings}",
+                "---ACTUAL WARNINGS---",
+                "{actual_warnings}",
+                "",
+                "",
+            ].join("\n"), {
+                input: input_formatted,
+                expected_warnings: expected_warnings,
+                actual_warnings: actual_warnings,
+            });
+            return false;
+        }
+    }
+    if (test.expect_stdout && (!test.node_version || semver.satisfies(process.version, test.node_version))) {
+        var stdout = [ sandbox.run_code(input_code), sandbox.run_code(input_code, true) ];
+        var toplevel = sandbox.has_toplevel({
+            compress: test.options,
+            mangle: test.mangle
+        });
+        var actual = stdout[toplevel ? 1 : 0];
+        if (test.expect_stdout === true || test.expect_stdout instanceof Error && test.expect_stdout.name === actual.name) {
+            test.expect_stdout = actual;
+        }
+        if (!sandbox.same_stdout(test.expect_stdout, actual)) {
+            log([
+                "!!! Invalid input or expected stdout",
+                "---INPUT---",
+                "{input}",
+                "---EXPECTED {expected_type}---",
+                "{expected}",
+                "---ACTUAL {actual_type}---",
+                "{actual}",
+                "",
+                "",
+            ].join("\n"), {
+                input: input_formatted,
+                expected_type: typeof test.expect_stdout == "string" ? "STDOUT" : "ERROR",
+                expected: test.expect_stdout,
+                actual_type: typeof actual == "string" ? "STDOUT" : "ERROR",
+                actual: actual,
+            });
+            return false;
+        }
+        actual = sandbox.run_code(output_code, toplevel);
+        if (!sandbox.same_stdout(test.expect_stdout, actual)) {
+            log([
+                "!!! failed",
+                "---INPUT---",
+                "{input}",
+                "---EXPECTED {expected_type}---",
+                "{expected}",
+                "---ACTUAL {actual_type}---",
+                "{actual}",
+                "",
+                "",
+            ].join("\n"), {
+                input: input_formatted,
+                expected_type: typeof test.expect_stdout == "string" ? "STDOUT" : "ERROR",
+                expected: test.expect_stdout,
+                actual_type: typeof actual == "string" ? "STDOUT" : "ERROR",
+                actual: actual,
+            });
+            return false;
+        }
+        if (!reminify(test.options, input_code, input_formatted, stdout)) {
+            return false;
+        }
+    }
+    return true;
+}
+
+function tmpl() {
+    return U.string_template.apply(null, arguments);
+}
+
+function to_toplevel(input, mangle_options) {
+    if (!(input instanceof U.AST_BlockStatement)) throw new Error("Unsupported input syntax");
+    var directive = true;
+    var offset = input.start.line;
+    var tokens = [];
+    var toplevel = new U.AST_Toplevel(input.transform(new U.TreeTransformer(function(node) {
+        if (U.push_uniq(tokens, node.start)) node.start.line -= offset;
+        if (!directive || node === input) return;
+        if (node instanceof U.AST_SimpleStatement && node.body instanceof U.AST_String) {
+            return new U.AST_Directive(node.body);
+        } else {
+            directive = false;
+        }
+    })));
+    toplevel.figure_out_scope(mangle_options);
+    return toplevel;
+}

test/compress/annotations.js

@@ -0,0 +1,473 @@
+issue_2629_1: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    beautify = {
+        comments: "all",
+    }
+    input: {
+        /*@__PURE__*/ a();
+        /*@__PURE__*/ (b());
+        (/*@__PURE__*/ c)();
+        (/*@__PURE__*/ d());
+    }
+    expect_exact: "c();"
+}
+
+issue_2629_2: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    beautify = {
+        comments: "all",
+    }
+    input: {
+        /*@__PURE__*/ a(1)(2)(3);
+        /*@__PURE__*/ (b(1))(2)(3);
+        /*@__PURE__*/ (c(1)(2))(3);
+        /*@__PURE__*/ (d(1)(2)(3));
+        (/*@__PURE__*/ e)(1)(2)(3);
+        (/*@__PURE__*/ f(1))(2)(3);
+        (/*@__PURE__*/ g(1)(2))(3);
+        (/*@__PURE__*/ h(1)(2)(3));
+    }
+    expect_exact: [
+        "e(1)(2)(3);",
+        "f(1)(2)(3);",
+        "g(1)(2)(3);",
+    ]
+}
+
+issue_2629_3: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    beautify = {
+        comments: "all",
+    }
+    input: {
+        /*@__PURE__*/ a.x(1).y(2).z(3);
+        /*@__PURE__*/ (b.x)(1).y(2).z(3);
+        /*@__PURE__*/ (c.x(1)).y(2).z(3);
+        /*@__PURE__*/ (d.x(1).y)(2).z(3);
+        /*@__PURE__*/ (e.x(1).y(2)).z(3);
+        /*@__PURE__*/ (f.x(1).y(2).z)(3);
+        /*@__PURE__*/ (g.x(1).y(2).z(3));
+        (/*@__PURE__*/ h).x(1).y(2).z(3);
+        (/*@__PURE__*/ i.x)(1).y(2).z(3);
+        (/*@__PURE__*/ j.x(1)).y(2).z(3);
+        (/*@__PURE__*/ k.x(1).y)(2).z(3);
+        (/*@__PURE__*/ l.x(1).y(2)).z(3);
+        (/*@__PURE__*/ m.x(1).y(2).z)(3);
+        (/*@__PURE__*/ n.x(1).y(2).z(3));
+    }
+    expect_exact: [
+        "h.x(1).y(2).z(3);",
+        "i.x(1).y(2).z(3);",
+        "j.x(1).y(2).z(3);",
+        "k.x(1).y(2).z(3);",
+        "l.x(1).y(2).z(3);",
+        "m.x(1).y(2).z(3);",
+    ]
+}
+
+issue_2629_4: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    input: {
+        (/*@__PURE__*/ x(), y());
+        (w(), /*@__PURE__*/ x(), y());
+    }
+    expect: {
+        y();
+        w(), y();
+    }
+}
+
+issue_2629_5: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    input: {
+        [ /*@__PURE__*/ x() ];
+        [ /*@__PURE__*/ x(), y() ];
+        [ w(), /*@__PURE__*/ x(), y() ];
+    }
+    expect: {
+        y();
+        w(), y();
+    }
+}
+
+issue_2638: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    beautify = {
+        comments: "all",
+    }
+    input: {
+        /*@__PURE__*/(g() || h())(x(), y());
+        (/*@__PURE__*/ (a() || b()))(c(), d());
+    }
+    expect_exact: [
+        "x(),y();",
+        "(a()||b())(c(),d());",
+    ]
+}
+
+issue_2705_1: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    beautify = {
+        comments: "all",
+    }
+    input: {
+        /*@__PURE__*/ new a();
+        /*@__PURE__*/ (new b());
+        new (/*@__PURE__*/ c)();
+        (/*@__PURE__*/ new d());
+    }
+    expect_exact: [
+        "new c;",
+    ]
+}
+
+issue_2705_2: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    beautify = {
+        comments: "all",
+    }
+    input: {
+        /*@__PURE__*/ new a(1)(2)(3);
+        /*@__PURE__*/ new (b(1))(2)(3);
+        /*@__PURE__*/ new (c(1)(2))(3);
+        /*@__PURE__*/ new (d(1)(2)(3));
+        new (/*@__PURE__*/ e)(1)(2)(3);
+        (/*@__PURE__*/ new f(1))(2)(3);
+        (/*@__PURE__*/ new g(1)(2))(3);
+        (/*@__PURE__*/ new h(1)(2)(3));
+    }
+    expect_exact: [
+        "new e(1)(2)(3);",
+        "new f(1)(2)(3);",
+        "new g(1)(2)(3);",
+    ]
+}
+
+issue_2705_3: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    beautify = {
+        comments: "all",
+    }
+    input: {
+        /*@__PURE__*/ new a.x(1).y(2).z(3);
+        /*@__PURE__*/ new (b.x)(1).y(2).z(3);
+        /*@__PURE__*/ new (c.x(1)).y(2).z(3);
+        /*@__PURE__*/ new (d.x(1).y)(2).z(3);
+        /*@__PURE__*/ new (e.x(1).y(2)).z(3);
+        /*@__PURE__*/ new (f.x(1).y(2).z)(3);
+        /*@__PURE__*/ new (g.x(1).y(2).z(3));
+        new (/*@__PURE__*/ h).x(1).y(2).z(3);
+        /* */ new (/*@__PURE__*/ i.x)(1).y(2).z(3);
+        (/*@__PURE__*/ new j.x(1)).y(2).z(3);
+        (/*@__PURE__*/ new k.x(1).y)(2).z(3);
+        (/*@__PURE__*/ new l.x(1).y(2)).z(3);
+        (/*@__PURE__*/ new m.x(1).y(2).z)(3);
+        (/*@__PURE__*/ new n.x(1).y(2).z(3));
+    }
+    expect_exact: [
+        "new h.x(1).y(2).z(3);",
+        "/* */new i.x(1).y(2).z(3);",
+        "new j.x(1).y(2).z(3);",
+        "new k.x(1).y(2).z(3);",
+        "new l.x(1).y(2).z(3);",
+        "new m.x(1).y(2).z(3);",
+    ]
+}
+
+issue_2705_4: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    input: {
+        (/*@__PURE__*/ new x(), y());
+        (w(), /*@__PURE__*/ new x(), y());
+    }
+    expect: {
+        y();
+        w(), y();
+    }
+}
+
+issue_2705_5: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    input: {
+        [ /*@__PURE__*/ new x() ];
+        [ /*@__PURE__*/ new x(), y() ];
+        [ w(), /*@__PURE__*/ new x(), y() ];
+    }
+    expect: {
+        y();
+        w(), y();
+    }
+}
+
+issue_2705_6: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    beautify = {
+        comments: "all",
+    }
+    input: {
+        /*@__PURE__*/new (g() || h())(x(), y());
+        /* */ new (/*@__PURE__*/ (a() || b()))(c(), d());
+    }
+    expect_exact: [
+        "x(),y();",
+        "/* */new(a()||b())(c(),d());",
+    ]
+}
+
+issue_3858: {
+    options = {
+        annotations: true,
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: false,
+        unused: true,
+    }
+    input: {
+        var f = function(a) {
+            return /*@__PURE__*/ function(b) {
+                console.log(b);
+            }(a);
+        };
+        f("PASS");
+    }
+    expect: {
+        var f = function(a) {
+            return function() {
+                console.log(a);
+            }();
+        };
+        f("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+inline_pure_call_1: {
+    options = {
+        annotations: true,
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: false,
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var f = function(a) {
+            return /*@__PURE__*/ function(b) {
+                console.log(b);
+            }(a);
+        };
+        f("PASS");
+    }
+    expect: {}
+}
+
+inline_pure_call_2: {
+    options = {
+        annotations: true,
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: false,
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var f = function(a) {
+            return /*@__PURE__*/ function(b) {
+                console.log(b);
+            }(a);
+        };
+        var a = f("PASS");
+    }
+    expect: {}
+}
+
+inline_pure_call_3: {
+    options = {
+        annotations: true,
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        keep_fargs: false,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var f = function(a) {
+            return /*@__PURE__*/ function(b) {
+                console.log(b);
+            }(a);
+        };
+        var a = f("PASS");
+        console.log(a);
+    }
+    expect: {
+        var a = function() {
+            console.log("PASS");
+        }();
+        console.log(a);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+    ]
+}
+
+inline_pure_call_4: {
+    options = {
+        annotations: true,
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = /*@__PURE__*/ function() {
+            return console.log("PASS"), 42;
+        }();
+        console.log(a);
+    }
+    expect: {
+        var a = function() {
+            return console.log("PASS"), 42;
+        }();
+        console.log(a);
+    }
+    expect_stdout: [
+        "PASS",
+        "42",
+    ]
+}
+
+compress_and_output_annotations_enabled: {
+    options = {
+        annotations: true,
+        side_effects: true,
+    }
+    beautify = {
+        annotations: true,
+        beautify: true,
+        comments: false,
+    }
+    input: {
+        var top = /*@__PURE__*/ foo();
+        /*@__PURE__*/ a(1)(2)(3);
+        /*@__PURE__*/ (b(1))(2)(3);
+        /*@__PURE__*/ (c(1)(2))(3);
+        /*@__PURE__*/ (d(1)(2)(3));
+        (/*@__PURE__*/ e)(1)(2)(3);
+        (/*@__PURE__*/ f(1))(2)(3);
+        (/*@__PURE__*/ g(1)(2))(3);
+        (/*@__PURE__*/ h(1)(2)(3));
+        /*@__PURE__*/ l(1).p(2);
+        (/*@__PURE__*/ m(1)).p(2);
+        (/*@__PURE__*/ n(1).p)(2);
+        (/*@__PURE__*/ o(1).p(2));
+    }
+    expect_exact: [
+        "var top = /*@__PURE__*/foo();",
+        "",
+        "e(1)(2)(3);",
+        "",
+        "f(1)(2)(3);",
+        "",
+        "g(1)(2)(3);",
+        "",
+        "m(1).p(2);",
+        "",
+        "n(1).p(2);",
+    ]
+}
+
+compress_annotations_disabled_output_annotations_enabled: {
+    options = {
+        annotations: false,
+        evaluate: true,
+        sequences: true,
+        side_effects: true,
+    }
+    beautify = {
+        annotations: true,
+        comments: true,
+    }
+    input: {
+        /*@__PURE__*/ a(1+2);
+        /*#__PURE__*/ (b(2+3));
+        (/*@__PURE__*/ c)(side_effect);
+        (/*#__PURE__*/ d(effect()));
+    }
+    expect_exact: [
+        "/*@__PURE__*/a(3),",
+        "/*#__PURE__*/b(5),",
+        "c(side_effect),",
+        "/*#__PURE__*/d(effect());",
+    ]
+}
+
+compress_and_output_annotations_disabled: {
+    options = {
+        annotations: false,
+        evaluate: true,
+        sequences: true,
+        side_effects: true,
+    }
+    beautify = {
+        annotations: false,
+        comments: true,
+    }
+    input: {
+        /*@__PURE__*/ a(1+2);
+        /*@__PURE__*/ (b(2+3));
+        (/*@__PURE__*/ c)(side_effect);
+        (/*@__PURE__*/ d(effect()));
+    }
+    expect_exact: [
+        "a(3),",
+        "b(5),",
+        "c(side_effect),",
+        "d(effect());",
+    ]
+}

test/compress/arrays.js

@@ -13,11 +13,13 @@ holes_and_undefined: {
     }
 }
 
-constant_join: {
+constant_join_1: {
     options = {
-        unsafe   : true,
-        evaluate : true
-    };
+        evaluate: true,
+        side_effects: true,
+        strings: true,
+        unsafe: true,
+    }
     input: {
         var a = [ "foo", "bar", "baz" ].join("");
         var a1 = [ "foo", "bar", "baz" ].join();
@@ -56,7 +58,7 @@ constant_join: {
         var c5 = [ boo() + bar() + "foo", 1, 2, 3, "bar", bar() + "foo" ].join();
         var c6 = [ "1,2,,,foo,bar", baz() ].join();
         var d = "foo-3bar-baz";
-        var e = [].join(foo + bar);
+        var e = (foo, bar, "");
         var f = "";
         var g = "";
     }
@@ -64,9 +66,10 @@ constant_join: {
 
 constant_join_2: {
     options = {
-        unsafe   : true,
-        evaluate : true
-    };
+        evaluate: true,
+        strings: true,
+        unsafe: true,
+    }
     input: {
         var a = [ "foo", "bar", boo(), "baz", "x", "y" ].join("");
         var b = [ "foo", "bar", boo(), "baz", "x", "y" ].join("-");
@@ -93,10 +96,12 @@ constant_join_2: {
 
 constant_join_3: {
     options = {
-        unsafe: true,
         evaluate: true,
-    };
+        strings: true,
+        unsafe: true,
+    }
     input: {
+        var foo, bar, baz;
         var a = [ null ].join();
         var b = [ , ].join();
         var c = [ , 1, , 3 ].join();
@@ -111,6 +116,7 @@ constant_join_3: {
         var l = [ foo, bar + "baz" ].join("");
     }
     expect: {
+        var foo, bar, baz;
         var a = "";
         var b = "";
         var c = ",1,,3";
@@ -128,50 +134,293 @@ constant_join_3: {
 
 for_loop: {
     options = {
-        unsafe      : true,
-        unused      : true,
-        evaluate    : true,
-        reduce_vars : true
-    };
+        evaluate: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        unsafe: true,
+        unused: true,
+    }
     input: {
         function f0() {
             var a = [1, 2, 3];
-            for (var i = 0; i < a.length; i++) {
-                console.log(a[i]);
-            }
+            var b = 0;
+            for (var i = 0; i < a.length; i++)
+                b += a[i];
+            return b;
         }
-
         function f1() {
             var a = [1, 2, 3];
-            for (var i = 0, len = a.length; i < len; i++) {
-                console.log(a[i]);
-            }
+            var b = 0;
+            for (var i = 0, len = a.length; i < len; i++)
+                b += a[i];
+            return b;
         }
-
-        function f2() {
-            var a = [1, 2, 3];
-            for (var i = 0; i < a.length; i++) {
-                a[i]++;
-            }
-        }
-    }
-    expect: {
-        function f0() {
-            var a = [1, 2, 3];
-            for (var i = 0; i < 3; i++)
-                console.log(a[i]);
-        }
-
-        function f1() {
-            var a = [1, 2, 3];
-            for (var i = 0; i < 3; i++)
-                console.log(a[i]);
-        }
-
         function f2() {
             var a = [1, 2, 3];
             for (var i = 0; i < a.length; i++)
                 a[i]++;
+            return a[2];
+        }
+        console.log(f0(), f1(), f2());
+    }
+    expect: {
+        function f0() {
+            var a = [1, 2, 3];
+            var b = 0;
+            for (var i = 0; i < 3; i++)
+                b += a[i];
+            return b;
+        }
+        function f1() {
+            var a = [1, 2, 3];
+            var b = 0;
+            for (var i = 0; i < 3; i++)
+                b += a[i];
+            return b;
+        }
+        function f2() {
+            var a = [1, 2, 3];
+            for (var i = 0; i < a.length; i++)
+                a[i]++;
+            return a[2];
+        }
+        console.log(f0(), f1(), f2());
+    }
+    expect_stdout: "6 6 4"
+}
+
+index: {
+    options = {
+        evaluate: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var a = [ 1, 2 ];
+        console.log(a[0], a[1]);
+    }
+    expect: {
+        console.log(1, 2);
+    }
+    expect_stdout: "1 2"
+}
+
+length: {
+    options = {
+        evaluate: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var a = [ 1, 2 ];
+        console.log(a.length);
+    }
+    expect: {
+        console.log(2);
+    }
+    expect_stdout: "2"
+}
+
+index_length: {
+    options = {
+        evaluate: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var a = [ 1, 2 ];
+        console.log(a[0], a.length);
+    }
+    expect: {
+        console.log(1, 2);
+    }
+    expect_stdout: "1 2"
+}
+
+constructor_bad: {
+    options = {
+        unsafe: true
+    }
+    input: {
+        try {
+            Array(NaN);
+            console.log("FAIL1");
+        } catch (ex) {
+            try {
+                new Array(NaN);
+                console.log("FAIL2");
+            } catch (ex) {
+                console.log("PASS");
+            }
+        }
+        try {
+            Array(3.14);
+            console.log("FAIL1");
+        } catch (ex) {
+            try {
+                new Array(3.14);
+                console.log("FAIL2");
+            } catch (ex) {
+                console.log("PASS");
+            }
         }
     }
+    expect: {
+        try {
+            Array(NaN);
+            console.log("FAIL1");
+        } catch (ex) {
+            try {
+                Array(NaN);
+                console.log("FAIL2");
+            } catch (ex) {
+                console.log("PASS");
+            }
+        }
+        try {
+            Array(3.14);
+            console.log("FAIL1");
+        } catch (ex) {
+            try {
+                Array(3.14);
+                console.log("FAIL2");
+            } catch (ex) {
+                console.log("PASS");
+            }
+        }
+    }
+    expect_stdout: [
+        "PASS",
+        "PASS",
+    ]
+    expect_warnings: [
+        "WARN: Invalid array length: 3.14 [test/compress/arrays.js:13,12]",
+        "WARN: Invalid array length: 3.14 [test/compress/arrays.js:17,16]",
+    ]
+}
+
+constructor_good: {
+    options = {
+        unsafe: true
+    }
+    input: {
+        console.log(Array());
+        console.log(Array(0));
+        console.log(Array(1));
+        console.log(Array(6));
+        console.log(Array(7));
+        console.log(Array(1, 2));
+        console.log(Array(false));
+        console.log(Array("foo"));
+        console.log(Array(Array));
+        console.log(new Array());
+        console.log(new Array(0));
+        console.log(new Array(1));
+        console.log(new Array(6));
+        console.log(new Array(7));
+        console.log(new Array(1, 2));
+        console.log(new Array(false));
+        console.log(new Array("foo"));
+        console.log(new Array(Array));
+    }
+    expect: {
+        console.log([]);
+        console.log([]);
+        console.log([,]);
+        console.log([,,,,,,]);
+        console.log(Array(7));
+        console.log([ 1, 2 ]);
+        console.log([ false ]);
+        console.log([ "foo" ]);
+        console.log(Array(Array));
+        console.log([]);
+        console.log([]);
+        console.log([,]);
+        console.log([,,,,,,]);
+        console.log(Array(7));
+        console.log([ 1, 2 ]);
+        console.log([ false ]);
+        console.log([ "foo" ]);
+        console.log(Array(Array));
+    }
+    expect_stdout: true
+    expect_warnings: []
+}
+
+unsafe_evaluate_modified_binary: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+    }
+    input: {
+        (function(a) {
+            (console && a).push(1);
+            if (a.length)
+                console.log("PASS");
+        })([]);
+    }
+    expect: {
+        (function(a) {
+            (console && a).push(1);
+            if (a.length)
+                console.log("PASS");
+        })([]);
+    }
+    expect_stdout: "PASS"
+}
+
+unsafe_evaluate_modified_conditional: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+    }
+    input: {
+        (function(a) {
+            (console ? a : []).push(1);
+            if (a.length)
+                console.log("PASS");
+        })([]);
+    }
+    expect: {
+        (function(a) {
+            (console ? a : []).push(1);
+            if (a.length)
+                console.log("PASS");
+        })([]);
+    }
+    expect_stdout: "PASS"
+}
+
+unsafe_evaluate_modified_sequence: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+    }
+    input: {
+        (function(a) {
+            (0, a).push(1);
+            if (a.length)
+                console.log("PASS");
+        })([]);
+    }
+    expect: {
+        (function(a) {
+            (0, a).push(1);
+            if (a.length)
+                console.log("PASS");
+        })([]);
+    }
+    expect_stdout: "PASS"
 }

test/compress/arrows.js

@@ -0,0 +1,816 @@
+no_funarg: {
+    input: {
+        (() => console.log(42))();
+    }
+    expect_exact: "(()=>console.log(42))();"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+single_funarg: {
+    input: {
+        (a => console.log(a))(42);
+    }
+    expect_exact: "(a=>console.log(a))(42);"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+multiple_funargs: {
+    input: {
+        ((a, b) => console.log(a, b))("foo", "bar");
+    }
+    expect_exact: '((a,b)=>console.log(a,b))("foo","bar");'
+    expect_stdout: "foo bar"
+    node_version: ">=4"
+}
+
+destructured_funarg: {
+    input: {
+        (([ a, b, c ]) => console.log(a, b, c))("foo");
+    }
+    expect_exact: '(([a,b,c])=>console.log(a,b,c))("foo");'
+    expect_stdout: "f o o"
+    node_version: ">=6"
+}
+
+await_parentheses: {
+    input: {
+        async function f() {
+            await (a => a);
+        }
+    }
+    expect_exact: "async function f(){await(a=>a)}"
+}
+
+for_parentheses_init: {
+    input: {
+        for (a => (a in a); console.log(42););
+    }
+    expect_exact: "for((a=>a in a);console.log(42););"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+for_parentheses_condition: {
+    input: {
+        for (console.log(42); a => (a in a);)
+            break;
+    }
+    expect_exact: "for(console.log(42);a=>a in a;)break;"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+for_parentheses_step: {
+    input: {
+        for (; console.log(42); a => (a in a));
+    }
+    expect_exact: "for(;console.log(42);a=>a in a);"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+for_assign_parentheses_init: {
+    input: {
+        for (f = a => (a in a); console.log(42););
+    }
+    expect_exact: "for((f=a=>a in a);console.log(42););"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+for_assign_parentheses_condition: {
+    input: {
+        for (console.log(42); f = a => (a in a);)
+            break;
+    }
+    expect_exact: "for(console.log(42);f=a=>a in a;)break;"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+for_assign_parentheses_step: {
+    input: {
+        for (; console.log(42); f = a => (a in a));
+    }
+    expect_exact: "for(;console.log(42);f=a=>a in a);"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+for_declaration_parentheses_init: {
+    input: {
+        for (var f = a => (a in a); console.log(42););
+    }
+    expect_exact: "for(var f=(a=>a in a);console.log(42););"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+for_statement_parentheses_init: {
+    input: {
+        for (a => {
+            a in a;
+        }; console.log(42););
+    }
+    expect_exact: "for(a=>{a in a};console.log(42););"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+body_call: {
+    input: {
+        (() => {
+            console.log("foo");
+            console.log("bar");
+        })();
+    }
+    expect_exact: '(()=>{console.log("foo");console.log("bar")})();'
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=4"
+}
+
+body_conditional: {
+    input: {
+        console.log((a => {}) ? "PASS" : "FAIL");
+    }
+    expect_exact: 'console.log((a=>{})?"PASS":"FAIL");'
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+destructured_object_value: {
+    input: {
+        console.log((a => ({} = a))(42));
+    }
+    expect_exact: "console.log((a=>({}=a))(42));"
+    expect_stdout: "42"
+    node_version: ">=6"
+}
+
+function_value: {
+    input: {
+        console.log((a => function() {
+            return a;
+        })(42)());
+    }
+    expect_exact: "console.log((a=>function(){return a})(42)());"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+in_value: {
+    input: {
+        console.log((a => a in {
+            foo: 42,
+        })("foo"));
+    }
+    expect_exact: 'console.log((a=>a in{foo:42})("foo"));'
+    expect_stdout: "true"
+    node_version: ">=4"
+}
+
+object_value: {
+    input: {
+        console.log((() => ({
+            4: 2,
+        }))()[4]);
+    }
+    expect_exact: "console.log((()=>({4:2}))()[4]);"
+    expect_stdout: "2"
+    node_version: ">=4"
+}
+
+object_first_in_value: {
+    input: {
+        console.log((a => ({
+            p: a,
+        }.p ? "FAIL" : "PASS"))());
+    }
+    expect_exact: 'console.log((a=>({p:a}).p?"FAIL":"PASS")());'
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+sequence_value: {
+    input: {
+        console.log((a => (console.log("foo"), a))("bar"));
+    }
+    expect_exact: 'console.log((a=>(console.log("foo"),a))("bar"));'
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=4"
+}
+
+side_effects_value: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        console.log((a => function() {
+            return a;
+        })(42)());
+    }
+    expect: {
+        console.log((a => function() {
+            return a;
+        })(42)());
+    }
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+arrow_property: {
+    input: {
+        console.log((a => 42).prototype);
+    }
+    expect_exact: "console.log((a=>42).prototype);"
+    expect_stdout: "undefined"
+    node_version: ">=4"
+}
+
+assign_arrow: {
+    input: {
+        var f = a => a;
+        console.log(f(42));
+    }
+    expect_exact: "var f=a=>a;console.log(f(42));"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+binary_arrow: {
+    input: {
+        console.log(4 || (() => 2));
+    }
+    expect_exact: "console.log(4||(()=>2));"
+    expect_stdout: "4"
+    node_version: ">=4"
+}
+
+unary_arrow: {
+    input: {
+        console.log(+(() => 42));
+    }
+    expect_exact: "console.log(+(()=>42));"
+    expect_stdout: "NaN"
+    node_version: ">=4"
+}
+
+trailing_comma: {
+    input: {
+        ((a,) => console.log(a))(42);
+    }
+    expect_exact: "(a=>console.log(a))(42);"
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+drop_arguments: {
+    options = {
+        arguments: true,
+        keep_fargs: false,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function() {
+            return () => arguments[0];
+        }("PASS")("FAIL"));
+    }
+    expect: {
+        console.log(function(argument_0) {
+            return () => argument_0;
+        }("PASS")("FAIL"));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+funarg_arguments: {
+    options = {
+        inline: true,
+    }
+    input: {
+        console.log((arguments => arguments)(42));
+    }
+    expect: {
+        console.log(42);
+    }
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+inline_arguments: {
+    options = {
+        inline: true,
+    }
+    input: {
+        console.log(function() {
+            return () => arguments[0];
+        }("PASS")("FAIL"));
+    }
+    expect: {
+        console.log(function() {
+            return () => arguments[0];
+        }("PASS")("FAIL"));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+var_arguments: {
+    options = {
+        inline: true,
+        properties: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            return () => {
+                var arguments = [ "PASS" ];
+                return arguments;
+            };
+        }("FAIL 1")("FAIL 2")[0]);
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+negate: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        if (!console ? 0 : () => 1)
+            console.log("PASS");
+    }
+    expect: {
+        (console ? () => 1 : 0) && console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+inline_this: {
+    options = {
+        inline: true,
+    }
+    input: {
+        var o = {
+            p: function() {
+                return function() {
+                    return () => this.q;
+                }();
+            },
+            q: "FAIL",
+        };
+        q = "PASS";
+        console.log(o.p()());
+    }
+    expect: {
+        var o = {
+            p: function() {
+                return function() {
+                    return () => this.q;
+                }();
+            },
+            q: "FAIL",
+        };
+        q = "PASS";
+        console.log(o.p()());
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+trim_body: {
+    options = {
+        arrows: true,
+        if_return: true,
+        side_effects: true,
+    }
+    input: {
+        var f = a => {
+            return a;
+        };
+        var g = b => void b;
+        console.log(f("PASS"), g("FAIL"));
+    }
+    expect: {
+        var f = a => a;
+        var g = b => {};
+        console.log(f("PASS"), g("FAIL"));
+    }
+    expect_stdout: "PASS undefined"
+    node_version: ">=4"
+}
+
+collapse_value: {
+    options = {
+        arrows: true,
+        collapse_vars: true,
+        keep_fargs: false,
+        unused: true,
+    }
+    input: {
+        var a = 42;
+        console.log((b => Math.floor(b))(a));
+    }
+    expect: {
+        var a = 42;
+        console.log((() => Math.floor(a))());
+    }
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+collapse_property_lambda: {
+    options = {
+        collapse_vars: true,
+        pure_getters: "strict",
+    }
+    input: {
+        console.log(function f() {
+            f.g = () => 42;
+            return f.g();
+        }());
+    }
+    expect: {
+        console.log(function f() {
+            return (f.g = () => 42)();
+        }());
+    }
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+drop_return: {
+    options = {
+        arrows: true,
+        side_effects: true,
+    }
+    input: {
+        (a => {
+            while (!console);
+            return console.log(a);
+        })(42);
+    }
+    expect: {
+        (a => {
+            while (!console);
+            console.log(a);
+        })(42);
+    }
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+drop_value: {
+    options = {
+        arrows: true,
+        side_effects: true,
+    }
+    input: {
+        ((a, b) => a + b)(console.log(42));
+    }
+    expect: {
+        ((a, b) => {})(console.log(42));
+    }
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+reduce_iife_1: {
+    options = {
+        evaluate: true,
+        keep_fargs: false,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (a => console.log(a + a))(21);
+    }
+    expect: {
+        (() => console.log(42))();
+    }
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+reduce_iife_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 21;
+        (() => console.log(a + a))();
+    }
+    expect: {
+        (() => console.log(42))();
+    }
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+reduce_iife_3: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "foo";
+        (() => {
+            console.log(a);
+            console.log(a);
+        })();
+        a = "bar";
+    }
+    expect: {
+        (() => {
+            console.log("foo");
+            console.log("foo");
+        })();
+    }
+    expect_stdout: [
+        "foo",
+        "foo",
+    ]
+    node_version: ">=4"
+}
+
+single_use_recursive: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            return (() => f)();
+        }
+        console.log(typeof f());
+    }
+    expect: {
+        console.log(typeof function f() {
+            return (() => f)();
+        }());
+    }
+    expect_stdout: "function"
+    node_version: ">=4"
+}
+
+issue_4388: {
+    options = {
+        inline: true,
+        toplevel: true,
+    }
+    input: {
+        (arguments => console.log(arguments && arguments))();
+    }
+    expect: {
+        (arguments => console.log(arguments && arguments))();
+    }
+    expect_stdout: "undefined"
+    node_version: ">=4"
+}
+
+issue_4390: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        function log() {
+            console.log.apply(console, arguments);
+        }
+        var a = 42, b = "FAIL";
+        b = "PASS";
+        (c => log(b, c))(a);
+        log(b);
+    }
+    expect: {
+        function log() {
+            console.log.apply(console, arguments);
+        }
+        var a = 42, b = "FAIL";
+        b = "PASS";
+        (c => log(b, c))(a);
+        log(b);
+    }
+    expect_stdout: [
+        "PASS 42",
+        "PASS",
+    ]
+    node_version: ">=4"
+}
+
+issue_4401: {
+    options = {
+        merge_vars: true,
+    }
+    input: {
+        (function() {
+            var a = (b => b(a))(console.log || a);
+            var c = console.log;
+            c && c(typeof b);
+        })();
+    }
+    expect: {
+        (function() {
+            var a = (b => b(a))(console.log || a);
+            var c = console.log;
+            c && c(typeof b);
+        })();
+    }
+    expect_stdout: [
+        "undefined",
+        "undefined",
+    ]
+    node_version: ">=4"
+}
+
+issue_4448: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+    }
+    input: {
+        var A;
+        try {
+            (arguments => {
+                arguments[0];
+            })(A);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        var A;
+        try {
+            (arguments => {
+                arguments[0];
+            })(A);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4476: {
+    options = {
+        arguments: true,
+    }
+    input: {
+        (function(a, b) {
+            (a => {
+                console.log(arguments[0], a);
+            })(b);
+        })("foo", "bar");
+    }
+    expect: {
+        (function(a, b) {
+            (a => {
+                console.log(arguments[0], a);
+            })(b);
+        })("foo", "bar");
+    }
+    expect_stdout: "foo bar"
+    node_version: ">=4"
+}
+
+issue_4666: {
+    input: {
+        console.log((a => /[0-9]/.test(a))(42));
+    }
+    expect_exact: "console.log((a=>/[0-9]/.test(a))(42));"
+    expect_stdout: "true"
+    node_version: ">=4"
+}
+
+issue_4685_1: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        new function(f) {
+            if (f() !== this)
+                console.log("PASS");
+        }(() => this);
+    }
+    expect: {
+        new function(f) {
+            if (f() !== this)
+                console.log("PASS");
+        }(() => this);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4685_2: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        new function(f) {
+            if (f() !== this)
+                console.log("PASS");
+        }(() => {
+            if (console)
+                return this;
+        });
+    }
+    expect: {
+        new function(f) {
+            if (f() !== this)
+                console.log("PASS");
+        }(() => {
+            if (console)
+                return this;
+        });
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4687_1: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        new function() {
+            console.log(function(f) {
+                return f() === this;
+            }(() => this) || "PASS");
+        }
+    }
+    expect: {
+        new function() {
+            console.log(function(f) {
+                return f() === this;
+            }(() => this) || "PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4687_2: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        new function() {
+            console.log(function(f) {
+                return f() === this;
+            }(() => {
+                if (console)
+                    return this;
+            }) || "PASS");
+        }
+    }
+    expect: {
+        new function() {
+            console.log(function(f) {
+                return f() === this;
+            }(() => {
+                if (console)
+                    return this;
+            }) || "PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4772: {
+    input: {
+        var f = a => (a)
+        /**/ console.log(f("PASS"));
+    }
+    expect_exact: 'var f=a=>a;console.log(f("PASS"));'
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}

test/compress/ascii.js

@@ -1,35 +0,0 @@
-ascii_only_true: {
-    options = {}
-    beautify = {
-        ascii_only : true,
-        ie8        : false,
-        beautify   : false,
-    }
-    input: {
-        function f() {
-            return "\x000\x001\x007\x008\x00" +
-                   "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f" +
-                   "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" +
-                   "\x20\x21\x22\x23 ... \x7d\x7e\x7f\x80\x81 ... \xfe\xff\u0fff\uffff";
-        }
-    }
-    expect_exact: 'function f(){return"\\x000\\x001\\x007\\08\\0"+"\\0\\x01\\x02\\x03\\x04\\x05\\x06\\x07\\b\\t\\n\\v\\f\\r\\x0e\\x0f"+"\\x10\\x11\\x12\\x13\\x14\\x15\\x16\\x17\\x18\\x19\\x1a\\x1b\\x1c\\x1d\\x1e\\x1f"+\' !"# ... }~\\x7f\\x80\\x81 ... \\xfe\\xff\\u0fff\\uffff\'}'
-}
-
-ascii_only_false: {
-    options = {}
-    beautify = {
-        ascii_only : false,
-        ie8        : false,
-        beautify   : false,
-    }
-    input: {
-        function f() {
-            return "\x000\x001\x007\x008\x00" +
-                   "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f" +
-                   "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" +
-                   "\x20\x21\x22\x23 ... \x7d\x7e\x7f\x80\x81 ... \xfe\xff\u0fff\uffff";
-        }
-    }
-    expect_exact: 'function f(){return"\\x000\\x001\\x007\\08\\0"+"\\0\x01\x02\x03\x04\x05\x06\x07\\b\\t\\n\\v\\f\\r\x0e\x0f"+"\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f"+\' !"# ... }~\x7f\x80\x81 ... \xfe\xff\u0fff\uffff\'}'
-}

test/compress/asm.js

@@ -1,25 +1,25 @@
 asm_mixed: {
     options = {
-        sequences     : true,
-        properties    : true,
-        dead_code     : true,
-        drop_debugger : true,
-        conditionals  : true,
-        comparisons   : true,
-        evaluate      : true,
-        booleans      : true,
-        loops         : true,
-        unused        : true,
-        hoist_funs    : true,
-        keep_fargs    : true,
-        keep_fnames   : false,
-        hoist_vars    : true,
-        if_return     : true,
-        join_vars     : true,
-        cascade       : true,
-        side_effects  : true,
-        negate_iife   : true
-    };
+        assignments: true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        drop_debugger: true,
+        evaluate: true,
+        hoist_funs: true,
+        hoist_vars: true,
+        if_return: true,
+        join_vars: true,
+        keep_fargs: true,
+        keep_fnames: false,
+        loops: true,
+        negate_iife: true,
+        properties: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
+    }
     input: {
         // adapted from http://asmjs.org/spec/latest/
         function asm_GeometricMean(stdlib, foreign, buffer) {
@@ -76,9 +76,8 @@ asm_mixed: {
                 start = start | 0;
                 end = end | 0;
                 var sum = 0.0, p = 0, q = 0;
-                for (p = start << 3, q = end << 3; (p | 0) < (q | 0); p = p + 8 | 0) {
+                for (p = start << 3, q = end << 3; (p | 0) < (q | 0); p = p + 8 | 0)
                     sum = sum + +log(values[p >> 3]);
-                }
                 return +sum;
             }
             function geometricMean(start, end) {
@@ -91,12 +90,12 @@ asm_mixed: {
         function no_asm_GeometricMean(stdlib, foreign, buffer) {
             function logSum(start, end) {
                 start |= 0, end |= 0;
-                var sum = 0, p = 0, q = 0;
-                for (p = start << 3, q = end << 3; (0 | p) < (0 | q); p = p + 8 | 0) sum += +log(values[p >> 3]);
+                for (var sum = 0, p = 0, q = 0, p = start << 3, q = end << 3; (0 | p) < (0 | q); p = p + 8 | 0)
+                    sum += +log(values[p >> 3]);
                 return +sum;
             }
             function geometricMean(start, end) {
-                return start |= 0, end |= 0, +exp(+logSum(start, end) / +(end - start | 0));
+                return start |= 0, end |= 0, +exp(+logSum(start, end) / (end - start | 0));
             }
             var exp = stdlib.Math.exp, log = stdlib.Math.log, values = new stdlib.Float64Array(buffer);
             return { geometricMean: geometricMean };
@@ -104,3 +103,131 @@ 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;'
+}
+
+issue_3636_1: {
+    mangle = {}
+    input: {
+        function n(stdlib, foreign, buffer) {
+            "use asm";
+            function add(x, y) {
+                x = x | 0;
+                y = y | 0;
+                return x + y | 0;
+            }
+            return {
+                add: add
+            };
+        }
+        console.log(new n().add("foo", 42));
+    }
+    expect: {
+        function n(o, e, u) {
+            "use asm";
+            function d(n, o) {
+                n = n | 0;
+                o = o | 0;
+                return n + o | 0;
+            }
+            return {
+                add: d
+            };
+        }
+        console.log(new n().add("foo", 42));
+    }
+    expect_stdout: "42"
+}
+
+issue_3636_2: {
+    mangle = {}
+    input: {
+        var n = function(stdlib, foreign, buffer) {
+            "use asm";
+            function add(x, y) {
+                x = x | 0;
+                y = y | 0;
+                return x + y | 0;
+            }
+            return {
+                add: add
+            };
+        };
+        console.log(new n().add("foo", 42));
+    }
+    expect: {
+        var n = function(n, o, e) {
+            "use asm";
+            function r(n, o) {
+                n = n | 0;
+                o = o | 0;
+                return n + o | 0;
+            }
+            return {
+                add: r
+            };
+        };
+        console.log(new n().add("foo", 42));
+    }
+    expect_stdout: "42"
+}

test/compress/assignment.js

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

test/compress/assignments.js

@@ -0,0 +1,703 @@
+op_equals_left_local_var: {
+    options = {
+        assignments: true,
+        evaluate: true,
+    }
+    input: {
+        var x;
+
+        x = x +   3;
+        x = x -   3;
+        x = x /   3;
+        x = x *   3;
+        x = x >>  3;
+        x = x <<  3;
+        x = x >>> 3;
+        x = x |   3;
+        x = x ^   3;
+        x = x %   3;
+        x = x &   3;
+
+        x = x +   g();
+        x = x -   g();
+        x = x /   g();
+        x = x *   g();
+        x = x >>  g();
+        x = x <<  g();
+        x = x >>> g();
+        x = x |   g();
+        x = x ^   g();
+        x = x %   g();
+        x = x &   g();
+    }
+    expect: {
+        var x;
+
+        x   += 3;
+        x   -= 3;
+        x   /= 3;
+        x   *= 3;
+        x  >>= 3;
+        x  <<= 3;
+        x >>>= 3;
+        x   |= 3;
+        x   ^= 3;
+        x   %= 3;
+        x   &= 3;
+
+        x   += g();
+        x   -= g();
+        x   /= g();
+        x   *= g();
+        x  >>= g();
+        x  <<= g();
+        x >>>= g();
+        x   |= g();
+        x   ^= g();
+        x   %= g();
+        x   &= g();
+    }
+}
+
+op_equals_right_local_var: {
+    options = {
+        assignments: true,
+        evaluate: true,
+    }
+    input: {
+        var x;
+
+        x = (x -= 2) ^ x;
+
+        x = 3 +   x;
+        x = 3 -   x;
+        x = 3 /   x;
+        x = 3 *   x;
+        x = 3 >>  x;
+        x = 3 <<  x;
+        x = 3 >>> x;
+        x = 3 |   x;
+        x = 3 ^   x;
+        x = 3 %   x;
+        x = 3 &   x;
+
+        x = g() +   x;
+        x = g() -   x;
+        x = g() /   x;
+        x = g() *   x;
+        x = g() >>  x;
+        x = g() <<  x;
+        x = g() >>> x;
+        x = g() |   x;
+        x = g() ^   x;
+        x = g() %   x;
+        x = g() &   x;
+    }
+    expect: {
+        var x;
+
+        x = (x -= 2) ^ x;
+
+        x = 3 + x;
+        x = 3 - x;
+        x = 3 / x;
+        x *= 3;
+        x = 3 >> x;
+        x = 3 << x;
+        x = 3 >>> x;
+        x |= 3;
+        x ^= 3;
+        x = 3 % x;
+        x &= 3;
+
+        x = g() +   x;
+        x = g() -   x;
+        x = g() /   x;
+        x = g() *   x;
+        x = g() >>  x;
+        x = g() <<  x;
+        x = g() >>> x;
+        x = g() |   x;
+        x = g() ^   x;
+        x = g() %   x;
+        x = g() &   x;
+    }
+}
+op_equals_left_global_var: {
+    options = {
+        assignments: true,
+        evaluate: true,
+    }
+    input: {
+        x = x +   3;
+        x = x -   3;
+        x = x /   3;
+        x = x *   3;
+        x = x >>  3;
+        x = x <<  3;
+        x = x >>> 3;
+        x = x |   3;
+        x = x ^   3;
+        x = x %   3;
+        x = x &   3;
+
+        x = x +   g();
+        x = x -   g();
+        x = x /   g();
+        x = x *   g();
+        x = x >>  g();
+        x = x <<  g();
+        x = x >>> g();
+        x = x |   g();
+        x = x ^   g();
+        x = x %   g();
+        x = x &   g();
+    }
+    expect: {
+        x   += 3;
+        x   -= 3;
+        x   /= 3;
+        x   *= 3;
+        x  >>= 3;
+        x  <<= 3;
+        x >>>= 3;
+        x   |= 3;
+        x   ^= 3;
+        x   %= 3;
+        x   &= 3;
+
+        x   += g();
+        x   -= g();
+        x   /= g();
+        x   *= g();
+        x  >>= g();
+        x  <<= g();
+        x >>>= g();
+        x   |= g();
+        x   ^= g();
+        x   %= g();
+        x   &= g();
+    }
+}
+
+op_equals_right_global_var: {
+    options = {
+        assignments: true,
+        evaluate: true,
+    }
+    input: {
+        x = (x -= 2) ^ x;
+
+        x = 3 +   x;
+        x = 3 -   x;
+        x = 3 /   x;
+        x = 3 *   x;
+        x = 3 >>  x;
+        x = 3 <<  x;
+        x = 3 >>> x;
+        x = 3 |   x;
+        x = 3 ^   x;
+        x = 3 %   x;
+        x = 3 &   x;
+
+        x = g() +   x;
+        x = g() -   x;
+        x = g() /   x;
+        x = g() *   x;
+        x = g() >>  x;
+        x = g() <<  x;
+        x = g() >>> x;
+        x = g() |   x;
+        x = g() ^   x;
+        x = g() %   x;
+        x = g() &   x;
+    }
+    expect: {
+        x = (x -= 2) ^ x;
+
+        x = 3 +   x;
+        x = 3 -   x;
+        x = 3 /   x;
+        x *= 3;
+        x = 3 >>  x;
+        x = 3 <<  x;
+        x = 3 >>> x;
+        x |= 3;
+        x ^= 3;
+        x = 3 %   x;
+        x &= 3;
+
+        x = g() +   x;
+        x = g() -   x;
+        x = g() /   x;
+        x = g() *   x;
+        x = g() >>  x;
+        x = g() <<  x;
+        x = g() >>> x;
+        x = g() |   x;
+        x = g() ^   x;
+        x = g() %   x;
+        x = g() &   x;
+    }
+}
+
+increment_decrement_1: {
+    options = {
+        assignments: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function(a) {
+            a += 1;
+            a -= 1;
+            return a;
+        }(42));
+    }
+    expect: {
+        console.log(function(a){
+            ++a;
+            --a;
+            return a;
+        }(42));
+    }
+    expect_stdout: "42"
+}
+
+increment_decrement_2: {
+    options = {
+        assignments: true,
+        passes: 2,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function(a) {
+            a = a + 1;
+            a = a - 1;
+            a += 1;
+            a -= 1;
+            return a;
+        }(42));
+    }
+    expect: {
+        console.log(function(a){
+            ++a;
+            --a;
+            ++a;
+            --a;
+            return a;
+        }(42));
+    }
+    expect_stdout: "42"
+}
+
+issue_3375_1: {
+    options = {
+        assignments: true,
+        reduce_vars: true,
+    }
+    input: {
+        function p(o) {
+            console.log(typeof o, o);
+        }
+        p(function(b) {
+            var a = b += 1;
+            --b;
+            return a;
+        }("object"));
+    }
+    expect: {
+        function p(o) {
+            console.log(typeof o, o);
+        }
+        p(function(b) {
+            var a = b += 1;
+            --b;
+            return a;
+        }("object"));
+    }
+    expect_stdout: "string object1"
+}
+
+issue_3375_2: {
+    options = {
+        assignments: true,
+        reduce_vars: true,
+    }
+    input: {
+        function p(o) {
+            console.log(typeof o, o);
+        }
+        p(function(b) {
+            var a = b -= 1;
+            --b;
+            return a;
+        }("object"));
+    }
+    expect: {
+        function p(o) {
+            console.log(typeof o, o);
+        }
+        p(function(b) {
+            var a = --b;
+            --b;
+            return a;
+        }("object"));
+    }
+    expect_stdout: "number NaN"
+}
+
+issue_3427: {
+    options = {
+        assignments: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var a;
+            a || (a = {});
+        })();
+    }
+    expect: {}
+}
+
+issue_3429_1: {
+    options = {
+        assignments: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        (function(b) {
+            b && (b = a = "FAIL");
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        (function(b) {
+            b = b && (a = "FAIL");
+        })();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3429_2: {
+    options = {
+        assignments: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        (function(b) {
+            b || (b = a = "FAIL");
+        })(42);
+        console.log(a);
+    }
+    expect: {
+        var a;
+        (function(b) {
+            b = b || (a = "FAIL");
+        })(42);
+        console.log(a);
+    }
+    expect_stdout: "undefined"
+}
+
+issue_3949_1: {
+    options = {
+        assignments: true,
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        var a = 42;
+        function f() {
+            var b = a;
+            b = b >> 2;
+            return 100 + b;
+        }
+        console.log(f());
+    }
+    expect: {
+        var a = 42;
+        function f() {
+            var b = a;
+            b >>= 2;
+            return 100 + b;
+        }
+        console.log(f());
+    }
+    expect_stdout: "110"
+}
+
+issue_3949_2: {
+    options = {
+        assignments: true,
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        var a = 42;
+        function f() {
+            var b = a;
+            b = 5 & b;
+            return 100 + b;
+        }
+        console.log(f());
+    }
+    expect: {
+        var a = 42;
+        function f() {
+            var b = a;
+            b &= 5;
+            return 100 + b;
+        }
+        console.log(f());
+    }
+    expect_stdout: "100"
+}
+
+issue_4521: {
+    options = {
+        assignments: true,
+        dead_code: true,
+    }
+    input: {
+        var a = (a = 42 | a) ? console.log(a) : 0;
+    }
+    expect: {
+        var a = (a |= 42) ? console.log(a) : 0;
+    }
+    expect_stdout: "42"
+}
+
+logical_assignments: {
+    input: {
+        var a = 42, b = null, c;
+        a &&= "foo";
+        b ||= "bar";
+        c ??= "baz";
+        console.log(a, b, c);
+    }
+    expect_exact: 'var a=42,b=null,c;a&&="foo";b||="bar";c??="baz";console.log(a,b,c);'
+    expect_stdout: "foo bar baz"
+    node_version: ">=15"
+}
+
+logical_collapse_vars: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = "FAIL", b = false;
+        a = "PASS";
+        b ??= a;
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL", b = false;
+        a = "PASS";
+        b ??= a;
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=15"
+}
+
+logical_reduce_vars: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS", b = 42;
+        b ??= a = "FAIL";
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS", b = 42;
+        b ??= a = "FAIL";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=15"
+}
+
+logical_side_effects: {
+    options = {
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS", b = 42;
+        b ??= a = "FAIL";
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS", b = 42;
+        b ??= a = "FAIL";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=15"
+}
+
+issue_4815_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        42..p &&= a = "FAIL";
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        42..p &&= a = "FAIL";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=15"
+}
+
+issue_4815_2: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+    }
+    input: {
+        var a = "PASS";
+        42..p &&= a = "FAIL";
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        42..p &&= a = "FAIL";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=15"
+}
+
+issue_4819: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        console.log(void 0 === ([].p &&= 42));
+    }
+    expect: {
+        console.log(void 0 === ([].p &&= 42));
+    }
+    expect_stdout: "true"
+    node_version: ">=15"
+}
+
+issue_4827_1: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        A = "FAIL";
+        var a = A, b = "PASS", c;
+        c &&= b = a, console.log(b);
+    }
+    expect: {
+        A = "FAIL";
+        var a = A, b = "PASS", c;
+        c &&= b = a, console.log(b);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=15"
+}
+
+issue_4827_2: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0, b = "PASS";
+        function f(c) {
+            a++,
+            c &&= b = a;
+        }
+        f();
+        console.log(b);
+    }
+    expect: {
+        var a = 0, b = "PASS";
+        a++,
+        c &&= b = a;
+        var c;
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=15"
+}
+
+issue_4827_3: {
+    options = {
+        merge_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 0, b, c;
+        a++;
+        c &&= b = a;
+        console.log(b);
+    }
+    expect: {
+        var a = 0, b, c;
+        a++;
+        c &&= b = a;
+        console.log(b);
+    }
+    expect_stdout: "undefined"
+    node_version: ">=15"
+}
+
+issue_4876: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        try {
+            var a = null;
+            var b = a &&= 42;
+            b.p;
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            var a = null;
+            var b = a &&= 42;
+            b.p;
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=15"
+}

test/compress/bigint.js

@@ -0,0 +1,92 @@
+arithmetic: {
+    input: {
+        console.log(((1n + 0x2n) * (0o3n - -4n)) >> (5n - 6n));
+    }
+    expect_exact: "console.log((1n+0x2n)*(0o3n- -4n)>>5n-6n);"
+    expect_stdout: "42n"
+    node_version: ">=10"
+}
+
+minus_dot: {
+    input: {
+        console.log(typeof -42n.toString(), typeof (-42n).toString());
+    }
+    expect_exact: "console.log(typeof-42n.toString(),typeof(-42n).toString());"
+    expect_stdout: "number string"
+    node_version: ">=10"
+}
+
+evaluate: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        console.log((0xDEAD_BEEFn).toString(16));
+    }
+    expect: {
+        console.log(0xdeadbeefn.toString(16));
+    }
+    expect_stdout: "deadbeef"
+    node_version: ">=10"
+}
+
+Number: {
+    options = {
+        unsafe: true,
+    }
+    input: {
+        console.log(Number(-0xfeed_dead_beef_badn));
+    }
+    expect: {
+        console.log(+("" + -0xfeed_dead_beef_badn));
+    }
+    expect_stdout: "-1148098955808013200"
+    node_version: ">=10"
+}
+
+issue_4590: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        A = 1;
+        0n || console.log("PASS");
+    }
+    expect: {
+        A = 1;
+        0n || console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}
+
+issue_4801: {
+    options = {
+        booleans: true,
+        collapse_vars: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        try {
+            (function(a) {
+                A = 42;
+                a || A;
+            })(!(0 == 42 >> 0o644n));
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            (function(a) {
+                0 != (A = 42) >> 0o644n || A;
+            })();
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}

test/compress/booleans.js

@@ -0,0 +1,183 @@
+iife_boolean_context: {
+    options = {
+        booleans: true,
+        evaluate: true,
+    }
+    input: {
+        console.log(function() {
+            return Object(1) || false;
+        }() ? "PASS" : "FAIL");
+        console.log(function() {
+            return [].length || true;
+        }() ? "PASS" : "FAIL");
+    }
+    expect: {
+        console.log(function() {
+            return Object(1);
+        }() ? "PASS" : "FAIL");
+        console.log(function() {
+            return [].length, 1;
+        }() ? "PASS" : "FAIL");
+    }
+    expect_stdout: [
+        "PASS",
+        "PASS",
+    ]
+    expect_warnings: [
+        "WARN: Dropping side-effect-free || [test/compress/booleans.js:2,19]",
+        "WARN: Boolean || always true [test/compress/booleans.js:5,19]",
+    ]
+}
+
+issue_3465_1: {
+    options = {
+        booleans: true,
+    }
+    input: {
+        console.log(function(a) {
+            return typeof a;
+        }() ? "PASS" : "FAIL");
+    }
+    expect: {
+        console.log(function(a) {
+            return 1;
+        }() ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3465_2: {
+    options = {
+        booleans: true,
+    }
+    input: {
+        console.log(function f(a) {
+            if (!a) console.log(f(42));
+            return typeof a;
+        }() ? "PASS" : "FAIL");
+    }
+    expect: {
+        console.log(function f(a) {
+            if (!a) console.log(f(42));
+            return typeof a;
+        }() ? "PASS" : "FAIL");
+    }
+    expect_stdout: [
+        "number",
+        "PASS",
+    ]
+}
+
+issue_3465_3: {
+    options = {
+        booleans: true,
+        passes: 2,
+        unused: true,
+    }
+    input: {
+        console.log(function f(a) {
+            return typeof a;
+        }() ? "PASS" : "FAIL");
+    }
+    expect: {
+        console.log(function(a) {
+            return 1;
+        }() ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_2737_2: {
+    options = {
+        booleans: true,
+        inline: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(bar) {
+            for (;bar();) break;
+        })(function qux() {
+            return console.log("PASS"), qux;
+        });
+    }
+    expect: {
+        (function(bar) {
+            for (;bar();) break;
+        })(function() {
+            return console.log("PASS"), 1;
+        });
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3658: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function f() {
+            console || f();
+            return "PASS";
+        }());
+    }
+    expect: {
+        console.log(function f() {
+            console || f();
+            return "PASS";
+        }());
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3690: {
+    options = {
+        booleans: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            return function() {
+                return a = [ this ];
+            }() ? "PASS" : "FAIL";
+        }());
+    }
+    expect: {
+        console.log(function(a) {
+            return function() {
+                return 1;
+            }() ? "PASS" : "FAIL";
+        }());
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4374: {
+    options = {
+        booleans: true,
+        conditionals: true,
+        if_return: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            console.log(f());
+            function f(a) {
+                if (null) return 0;
+                if (a) return 1;
+                return 0;
+            }
+        })();
+    }
+    expect: {
+        (function() {
+            console.log(function(a) {
+                return !null && a ? 1 : 0;
+            }());
+        })();
+    }
+    expect_stdout: "0"
+}

test/compress/comparing.js

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

test/compress/comparisons.js

@@ -0,0 +1,495 @@
+comparisons: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        var obj1, obj2;
+        var result1 = obj1 <= obj2;
+        var result2 = obj1 <  obj2;
+        var result3 = obj1 >= obj2;
+        var result4 = obj1 >  obj2;
+    }
+    expect: {
+        var obj1, obj2;
+        var result1 = obj1 <= obj2;
+        var result2 = obj1 <  obj2;
+        var result3 = obj2 <= obj1;
+        var result4 = obj2 <  obj1;
+    }
+}
+
+unsafe_comps: {
+    options = {
+        comparisons: true,
+        conditionals: true,
+        unsafe_comps: true,
+    }
+    input: {
+        var obj1, obj2;
+        obj1 <= obj2 ? f1() : g1();
+        obj1 <  obj2 ? f2() : g2();
+        obj1 >= obj2 ? f3() : g3();
+        obj1 >  obj2 ? f4() : g4();
+    }
+    expect: {
+        var obj1, obj2;
+        (obj2 <  obj1 ? g1 : f1)();
+        (obj1 <  obj2 ? f2 : g2)();
+        (obj1 <  obj2 ? g3 : f3)();
+        (obj2 <  obj1 ? f4 : g4)();
+    }
+}
+
+dont_change_in_or_instanceof_expressions: {
+    input: {
+        1 in 1;
+        null in null;
+        1 instanceof 1;
+        null instanceof null;
+    }
+    expect: {
+        1 in 1;
+        null in null;
+        1 instanceof 1;
+        null instanceof null;
+    }
+}
+
+self_comparison_1: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        a === a;
+        a !== b;
+        b.c === a.c;
+        b.c !== b.c;
+    }
+    expect: {
+        a == a;
+        a !== b;
+        b.c === a.c;
+        b.c != b.c;
+    }
+}
+
+self_comparison_2: {
+    options = {
+        comparisons: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        function f() {}
+        var o = {};
+        console.log(f != f, o === o);
+    }
+    expect: {
+        function f() {}
+        var o = {};
+        console.log(false, true);
+    }
+    expect_stdout: "false true"
+}
+
+self_comparison_3: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        var a;
+        function f() {
+            var b = a;
+            a = null;
+            return b;
+        }
+        for (var i = 0; i < 2; i++)
+            console.log(f() === f());
+    }
+    expect: {
+        var a;
+        function f() {
+            var b = a;
+            a = null;
+            return b;
+        }
+        for (var i = 0; i < 2; i++)
+            console.log(f() === f());
+    }
+    expect_stdout: [
+        "false",
+        "true",
+    ]
+}
+
+self_comparison_4: {
+    options = {
+        booleans: true,
+        comparisons: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {};
+        console.log(o == o, o != o);
+        console.log(o === o, o !== o);
+    }
+    expect: {
+        console.log(!0, !1);
+        console.log(!0, !1);
+    }
+    expect_stdout: [
+        "true false",
+        "true false",
+    ]
+}
+
+issue_2857_1: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        function f1(a) {
+            a === undefined || a === null;
+            a === undefined || a !== null;
+            a !== undefined || a === null;
+            a !== undefined || a !== null;
+            a === undefined && a === null;
+            a === undefined && a !== null;
+            a !== undefined && a === null;
+            a !== undefined && a !== null;
+        }
+        function f2(a) {
+            a === null || a === undefined;
+            a === null || a !== undefined;
+            a !== null || a === undefined;
+            a !== null || a !== undefined;
+            a === null && a === undefined;
+            a === null && a !== undefined;
+            a !== null && a === undefined;
+            a !== null && a !== undefined;
+        }
+    }
+    expect: {
+        function f1(a) {
+            null == a;
+            void 0 === a || null !== a;
+            void 0 !== a || null === a;
+            void 0 !== a || null !== a;
+            void 0 === a && null === a;
+            void 0 === a && null !== a;
+            void 0 !== a && null === a;
+            null != a;
+        }
+        function f2(a) {
+            null == a;
+            null === a || void 0 !== a;
+            null !== a || void 0 === a;
+            null !== a || void 0 !== a;
+            null === a && void 0 === a;
+            null === a && void 0 !== a;
+            null !== a && void 0 === a;
+            null != a;
+        }
+    }
+}
+
+issue_2857_2: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        function f(a, p) {
+            a === undefined || a === null || p;
+            a === undefined || a !== null || p;
+            a !== undefined || a === null || p;
+            a !== undefined || a !== null || p;
+            a === undefined && a === null || p;
+            a === undefined && a !== null || p;
+            a !== undefined && a === null || p;
+            a !== undefined && a !== null || p;
+        }
+    }
+    expect: {
+        function f(a, p) {
+            null == a || p;
+            void 0 === a || null !== a || p;
+            void 0 !== a || null === a || p;
+            void 0 !== a || null !== a || p;
+            void 0 === a && null === a || p;
+            void 0 === a && null !== a || p;
+            void 0 !== a && null === a || p;
+            null != a || p;
+        }
+    }
+}
+
+issue_2857_3: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        function f(a, p) {
+            a === undefined || a === null && p;
+            a === undefined || a !== null && p;
+            a !== undefined || a === null && p;
+            a !== undefined || a !== null && p;
+            a === undefined && a === null && p;
+            a === undefined && a !== null && p;
+            a !== undefined && a === null && p;
+            a !== undefined && a !== null && p;
+        }
+    }
+    expect: {
+        function f(a, p) {
+            void 0 === a || null === a && p;
+            void 0 === a || null !== a && p;
+            void 0 !== a || null === a && p;
+            void 0 !== a || null !== a && p;
+            void 0 === a && null === a && p;
+            void 0 === a && null !== a && p;
+            void 0 !== a && null === a && p;
+            null != a && p;
+        }
+    }
+}
+
+issue_2857_4: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        function f(a, p) {
+            p || a === undefined || a === null;
+            p || a === undefined || a !== null;
+            p || a !== undefined || a === null;
+            p || a !== undefined || a !== null;
+            p || a === undefined && a === null;
+            p || a === undefined && a !== null;
+            p || a !== undefined && a === null;
+            p || a !== undefined && a !== null;
+        }
+    }
+    expect: {
+        function f(a, p) {
+            p || null == a;
+            p || void 0 === a || null !== a;
+            p || void 0 !== a || null === a;
+            p || void 0 !== a || null !== a;
+            p || void 0 === a && null === a;
+            p || void 0 === a && null !== a;
+            p || void 0 !== a && null === a;
+            p || null != a;
+        }
+    }
+}
+
+issue_2857_5: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        function f(a, p) {
+            p && a === undefined || a === null;
+            p && a === undefined || a !== null;
+            p && a !== undefined || a === null;
+            p && a !== undefined || a !== null;
+            p && a === undefined && a === null;
+            p && a === undefined && a !== null;
+            p && a !== undefined && a === null;
+            p && a !== undefined && a !== null;
+        }
+    }
+    expect: {
+        function f(a, p) {
+            p && void 0 === a || null === a;
+            p && void 0 === a || null !== a;
+            p && void 0 !== a || null === a;
+            p && void 0 !== a || null !== a;
+            p && void 0 === a && null === a;
+            p && void 0 === a && null !== a;
+            p && void 0 !== a && null === a;
+            p && null != a;
+        }
+    }
+}
+
+issue_2857_6: {
+    options = {
+        comparisons: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+    }
+    input: {
+        function f(a) {
+            if (({}).b === undefined || {}.b === null)
+                return a.b !== undefined && a.b !== null;
+        }
+        console.log(f({
+            a: [ null ],
+            get b() {
+                return this.a.shift();
+            }
+        }));
+    }
+    expect: {
+        function f(a) {
+            if (null == {}.b)
+                return void 0 !== a.b && null !== a.b;
+        }
+        console.log(f({
+            a: [ null ],
+            get b() {
+                return this.a.shift();
+            }
+        }));
+    }
+    expect_stdout: "true"
+}
+
+is_boolean_unsafe: {
+    options = {
+        comparisons: true,
+        unsafe: true,
+    }
+    input: {
+        console.log(/foo/.test("bar") === [].isPrototypeOf({}));
+    }
+    expect: {
+        console.log(/foo/.test("bar") == [].isPrototypeOf({}));
+    }
+    expect_stdout: "true"
+}
+
+is_number_unsafe: {
+    options = {
+        comparisons: true,
+        unsafe: true,
+    }
+    input: {
+        console.log(Math.acos(42) !== "foo".charCodeAt(4));
+    }
+    expect: {
+        console.log(Math.acos(42) != "foo".charCodeAt(4));
+    }
+    expect_stdout: "true"
+}
+
+is_boolean_var: {
+    options = {
+        comparisons: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function(a, b) {
+            for (var i = 0, c = !b; i < a.length; i++)
+                if (!a[i] === c)
+                    return i;
+        }([ false, true ], 42));
+    }
+    expect: {
+        console.log(function(a, b) {
+            for (var i = 0, c = !b; i < a.length; i++)
+                if (!a[i] == c)
+                    return i;
+        }([ false, true ], 42));
+    }
+    expect_stdout: "1"
+}
+
+is_defined: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        console.log(function a() {
+            return void 0 === a;
+        }());
+    }
+    expect: {
+        console.log(function a() {
+            return a, false;
+        }());
+    }
+    expect_stdout: "false"
+    expect_warnings: [
+        "WARN: Expression always defined [test/compress/comparisons.js:2,19]",
+    ]
+}
+
+unsafe_indexOf: {
+    options = {
+        booleans: true,
+        comparisons: true,
+        unsafe: true,
+    }
+    input: {
+        var a = Object.keys({ foo: 42 });
+        if (a.indexOf("bar") < 0) console.log("PASS");
+        if (0 > a.indexOf("bar")) console.log("PASS");
+        if (a.indexOf("foo") >= 0) console.log("PASS");
+        if (0 <= a.indexOf("foo")) console.log("PASS");
+        if (a.indexOf("foo") > -1) console.log("PASS");
+        if (-1 < a.indexOf("foo")) console.log("PASS");
+        if (a.indexOf("bar") == -1) console.log("PASS");
+        if (-1 == a.indexOf("bar")) console.log("PASS");
+        if (a.indexOf("bar") === -1) console.log("PASS");
+        if (-1 === a.indexOf("bar")) console.log("PASS");
+        if (a.indexOf("foo") != -1) console.log("PASS");
+        if (-1 != a.indexOf("foo")) console.log("PASS");
+        if (a.indexOf("foo") !== -1) console.log("PASS");
+        if (-1 !== a.indexOf("foo")) console.log("PASS");
+    }
+    expect: {
+        var a = Object.keys({ foo: 42 });
+        if (!~a.indexOf("bar")) console.log("PASS");
+        if (!~a.indexOf("bar")) console.log("PASS");
+        if (~a.indexOf("foo")) console.log("PASS");
+        if (~a.indexOf("foo")) console.log("PASS");
+        if (~a.indexOf("foo")) console.log("PASS");
+        if (~a.indexOf("foo")) console.log("PASS");
+        if (!~a.indexOf("bar")) console.log("PASS");
+        if (!~a.indexOf("bar")) console.log("PASS");
+        if (!~a.indexOf("bar")) console.log("PASS");
+        if (!~a.indexOf("bar")) console.log("PASS");
+        if (~a.indexOf("foo")) console.log("PASS");
+        if (~a.indexOf("foo")) console.log("PASS");
+        if (~a.indexOf("foo")) console.log("PASS");
+        if (~a.indexOf("foo")) console.log("PASS");
+    }
+    expect_stdout: [
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+        "PASS",
+    ]
+}
+
+issue_3413: {
+    options = {
+        comparisons: true,
+        evaluate: true,
+        side_effects: true,
+    }
+    input: {
+        var b;
+        void 0 !== ("" < b || void 0) || console.log("PASS");
+    }
+    expect: {
+        var b;
+        void 0 !== ("" < b || void 0) || console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}

test/compress/concat-strings.js

@@ -1,7 +1,7 @@
 concat_1: {
     options = {
-        evaluate: true
-    };
+        evaluate: true,
+    }
     input: {
         var a = "foo" + "bar" + x() + "moo" + "foo" + y() + "x" + "y" + "z" + q();
         var b = "foo" + 1 + x() + 2 + "boo";
@@ -21,12 +21,14 @@ concat_1: {
         var c = 1 + x() + 2 + "boo";
         var d = 1 + x() + 2 + 3 + "boo";
         var e = 1 + x() + 2 + "X3boo";
-        var f = "\x00360\08\0";
+        var f = "\x00360\x008\0";
     }
 }
 
 concat_2: {
-    options = {};
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             1 + (2 + 3),
@@ -55,7 +57,9 @@ concat_2: {
 }
 
 concat_3: {
-    options = {};
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             1 + 2 + (3 + 4 + 5),
@@ -84,7 +88,9 @@ concat_3: {
 }
 
 concat_4: {
-    options = {};
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             1 + "2" + (3 + 4 + 5),
@@ -113,7 +119,9 @@ concat_4: {
 }
 
 concat_5: {
-    options = {};
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             "1" + 2 + (3 + 4 + 5),
@@ -142,7 +150,9 @@ concat_5: {
 }
 
 concat_6: {
-    options = {};
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             "1" + "2" + (3 + 4 + 5),
@@ -171,6 +181,9 @@ concat_6: {
 }
 
 concat_7: {
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             "" + 1,
@@ -197,6 +210,9 @@ concat_7: {
 }
 
 concat_8: {
+    options = {
+        strings: true,
+    }
     input: {
         console.log(
             1 + "",
@@ -221,3 +237,55 @@ concat_8: {
     }
     expect_stdout: true
 }
+
+concat_9: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        reduce_vars: true,
+        strings: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "foo";
+        console.log(
+            12 + (34 + a),
+            null + (34 + a),
+            12 + (null + a),
+            false + (34 + a),
+            12 + (false + a),
+            "bar" + (34 + a),
+            12 + ("bar" + a)
+        );
+    }
+    expect: {
+        var a = "foo";
+        console.log(
+            "1234" + a,
+            "null34" + a,
+            "12null" + a,
+            !1 + (34 + a),
+            12 + (!1 + a),
+            "bar34" + a,
+            "12bar" + a
+        );
+    }
+    expect_stdout: true
+}
+
+issue_3689: {
+    options = {
+        strings: true,
+    }
+    input: {
+        console.log(function(a) {
+            return a + ("" + (a[0] = 0));
+        }([]));
+    }
+    expect: {
+        console.log(function(a) {
+            return a + ("" + (a[0] = 0));
+        }([]));
+    }
+    expect_stdout: "00"
+}

test/compress/debugger.js

@@ -1,7 +1,7 @@
 keep_debugger: {
     options = {
-        drop_debugger: false
-    };
+        drop_debugger: false,
+    }
     input: {
         debugger;
     }
@@ -12,8 +12,8 @@ keep_debugger: {
 
 drop_debugger: {
     options = {
-        drop_debugger: true
-    };
+        drop_debugger: true,
+    }
     input: {
         debugger;
         if (foo) debugger;

test/compress/directives.js

@@ -0,0 +1,131 @@
+simple_statement_is_not_a_directive: {
+    input: {
+        "use strict"
+            .split(" ")
+            .forEach(function(s) {
+                console.log(s);
+            });
+        console.log(!this); // is strict mode?
+        (function() {
+            "directive"
+            ""
+            "use strict"
+            "hello world"
+                .split(" ")
+                .forEach(function(s) {
+                    console.log(s);
+                });
+            console.log(!this); // is strict mode?
+        })();
+    }
+    expect: {
+        "use strict".split(" ").forEach(function(s) {
+            console.log(s);
+        });
+        console.log(!this);
+        (function() {
+            "directive";
+            "";
+            "use strict";
+            "hello world".split(" ").forEach(function(s) {
+                console.log(s);
+            });
+            console.log(!this);
+        })();
+    }
+    expect_stdout: [
+        "use",
+        "strict",
+        "false",
+        "hello",
+        "world",
+        "true",
+    ]
+}
+
+drop_lone_use_strict: {
+    options = {
+        directives: true,
+        unused: true,
+    }
+    input: {
+        function f1() {
+            "use strict";
+        }
+        function f2() {
+            "use strict";
+            function f3() {
+                "use strict";
+            }
+        }
+        (function f4() {
+            "use strict";
+        })();
+    }
+    expect: {
+        function f1() {
+        }
+        function f2() {
+        }
+        (function() {})();
+    }
+}
+
+issue_3166: {
+    options = {
+        directives: true,
+    }
+    input: {
+        "foo";
+        "use strict";
+        function f() {
+            "use strict";
+            "bar";
+            "use asm";
+        }
+    }
+    expect: {
+        "use strict";
+        function f() {
+            "use asm";
+        }
+    }
+}
+
+valid_after_invalid_1: {
+    input: {
+        console.log(typeof function() {
+            "use\x20strict";
+            "use strict";
+            return this;
+        }());
+    }
+    expect: {
+        console.log(typeof function() {
+            "use\x20strict";
+            "use strict";
+            return this;
+        }());
+    }
+    expect_stdout: "undefined"
+}
+
+valid_after_invalid_2: {
+    options = {
+        directives: true,
+    }
+    input: {
+        console.log(typeof function() {
+            "use\x20strict";
+            "use strict";
+            return this;
+        }());
+    }
+    expect: {
+        console.log(typeof function() {
+            "use strict";
+            return this;
+        }());
+    }
+    expect_stdout: "undefined"
+}

test/compress/drop-console.js

@@ -1,5 +1,5 @@
 drop_console_1: {
-    options = {};
+    options = {}
     input: {
         console.log('foo');
         console.log.apply(console, arguments);
@@ -11,7 +11,9 @@ drop_console_1: {
 }
 
 drop_console_2: {
-    options = { drop_console: true };
+    options = {
+        drop_console: true,
+    }
     input: {
         console.log('foo');
         console.log.apply(console, arguments);

test/compress/exponentiation.js

@@ -0,0 +1,147 @@
+precedence_1: {
+    input: {
+        console.log(-4 ** 3 ** 2);
+    }
+    expect_exact: "console.log((-4)**3**2);"
+    expect_stdout: "-262144"
+    node_version: ">=8"
+}
+
+precedence_2: {
+    input: {
+        console.log(-4 ** (3 ** 2));
+    }
+    expect_exact: "console.log((-4)**3**2);"
+    expect_stdout: "-262144"
+    node_version: ">=8"
+}
+
+precedence_3: {
+    input: {
+        console.log(-(4 ** 3) ** 2);
+    }
+    expect_exact: "console.log((-(4**3))**2);"
+    expect_stdout: "4096"
+    node_version: ">=8"
+}
+
+precedence_4: {
+    input: {
+        console.log((-4 ** 3) ** 2);
+    }
+    expect_exact: "console.log(((-4)**3)**2);"
+    expect_stdout: "4096"
+    node_version: ">=8"
+}
+
+await: {
+    input: {
+        (async a => a * await a ** ++a % a)(2).then(console.log);
+    }
+    expect_exact: "(async a=>a*(await a)**++a%a)(2).then(console.log);"
+    expect_stdout: "1"
+    node_version: ">=8"
+}
+
+assignment_1: {
+    input: {
+        var a = 2;
+        a **= 5;
+        console.log(a);
+    }
+    expect_exact: "var a=2;a**=5;console.log(a);"
+    expect_stdout: "32"
+    node_version: ">=8"
+}
+
+assignment_2: {
+    input: {
+        var a = 8n;
+        a **= a;
+        console.log(a);
+    }
+    expect_exact: "var a=8n;a**=a;console.log(a);"
+    expect_stdout: "16777216n"
+    node_version: ">=10"
+}
+
+evaluate: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log(1 + 2 ** 3 - 4);
+    }
+    expect: {
+        console.log(5);
+    }
+    expect_stdout: "5"
+    node_version: ">=8"
+}
+
+issue_4664: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            new function(a) {
+                console.log(typeof f, a, typeof this);
+            }((A = 0, (NaN ^ 1) * 2 ** 30), 0);
+        }
+        f();
+    }
+    expect: {
+        (function f() {
+            new function(a) {
+                console.log(typeof f, 1073741824, typeof this);
+            }(A = 0);
+        })();
+    }
+    expect_stdout: "function 1073741824 object"
+    node_version: ">=8"
+}
+
+issue_4715: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        A = 1;
+        console.log((-0) ** A + 0);
+        console.log((-0) ** A - 0);
+        console.log((-0) ** A * 1);
+        console.log((-0) ** A / 1);
+        console.log(Math.pow(-0, A) + 0);
+        console.log(Math.pow(-0, A) - 0);
+        console.log(Math.pow(-0, A) * 1);
+        console.log(Math.pow(-0, A) / 1);
+    }
+    expect: {
+        A = 1;
+        console.log((-0) ** A + 0);
+        console.log((-0) ** A);
+        console.log((-0) ** A * 1);
+        console.log((-0) ** A);
+        console.log(Math.pow(-0, A) + 0);
+        console.log(+Math.pow(-0, A));
+        console.log(+Math.pow(-0, A));
+        console.log(+Math.pow(-0, A));
+    }
+    expect_stdout: [
+        "0",
+        "-0",
+        "-0",
+        "-0",
+        "0",
+        "-0",
+        "-0",
+        "-0",
+    ]
+    node_version: ">=8"
+}

test/compress/exports.js

@@ -0,0 +1,498 @@
+refs: {
+    input: {
+        export {};
+        export { a, b as B, c as case, d as default };
+    }
+    expect_exact: "export{};export{a,b as B,c as case,d as default};"
+}
+
+var_defs: {
+    input: {
+        export const a = 1;
+        export let b = 2, c = 3;
+        export var { d, e: [] } = f;
+    }
+    expect_exact: "export const a=1;export let b=2,c=3;export var{d,e:[]}=f;"
+}
+
+defuns: {
+    input: {
+        export class A {}
+        export function e() {}
+        export function* f(a) {}
+        export async function g(b, c) {}
+        export async function* h({}, ...[]) {}
+    }
+    expect_exact: "export class A{}export function e(){}export function*f(a){}export async function g(b,c){}export async function*h({},...[]){}"
+}
+
+defaults: {
+    input: {
+        export default 42;
+        export default async;
+        export default (x, y) => x * x;
+        export default class {};
+        export default function*(a, b) {};
+        export default async function f({ c }, ...[ d ]) {};
+    }
+    expect_exact: "export default 42;export default async;export default(x,y)=>x*x;export default class{}export default function*(a,b){}export default async function f({c},...[d]){}"
+}
+
+defaults_parentheses_1: {
+    input: {
+        export default function() {
+            console.log("FAIL");
+        }(console.log("PASS"));
+    }
+    expect_exact: 'export default function(){console.log("FAIL")}console.log("PASS");'
+}
+
+defaults_parentheses_2: {
+    input: {
+        export default (async function() {
+            console.log("PASS");
+        })();
+    }
+    expect_exact: 'export default(async function(){console.log("PASS")})();'
+}
+
+defaults_parentheses_3: {
+    input: {
+        export default (42, "PASS");
+    }
+    expect_exact: 'export default(42,"PASS");'
+}
+
+defaults_parentheses_4: {
+    input: {
+        export default (function f() {});
+    }
+    expect_exact: "export default(function f(){});"
+}
+
+defaults_parentheses_5: {
+    input: {
+        export default (function(a) {
+            console.log(a[0]);
+        }`PASS`);
+    }
+    expect_exact: "export default(function(a){console.log(a[0])})`PASS`;"
+}
+
+defaults_parentheses_6: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        export default !function() {
+            while (!console);
+        }() ? "PASS" : "FAIL";
+    }
+    expect_exact: 'export default(function(){while(!console);})()?"FAIL":"PASS";'
+}
+
+defaults_regexp: {
+    input: {
+        export default /foo/;
+    }
+    expect_exact: "export default/foo/;"
+}
+
+foreign: {
+    input: {
+        export * from "foo";
+        export {} from "bar";
+        export * as a from "baz";
+        export { default } from "moo";
+        export { b, c as case, default as delete, d } from "moz";
+    }
+    expect_exact: 'export*from"foo";export{}from"bar";export*as a from"baz";export{default}from"moo";export{b,c as case,default as delete,d}from"moz";'
+}
+
+same_quotes: {
+    beautify = {
+        beautify: true,
+        quote_style: 3,
+    }
+    input: {
+        export * from 'foo';
+        export {} from "bar";
+    }
+    expect_exact: [
+        "export * from 'foo';",
+        "",
+        'export {} from "bar";',
+    ]
+}
+
+drop_unused: {
+    options = {
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        export default 42;
+        export default (x, y) => x * x;
+        export default class A extends B { get p() { h() } }
+        export default function*(a, b) {}
+        export default async function f({ c }, ...[ d ]) {}
+        export var e;
+        export function g(x, [ y ], ...z) {}
+        function h() {}
+    }
+    expect: {
+        export default 42;
+        export default (x, y) => x * x;
+        export default class extends B { get p() { h() } }
+        export default function*(a, b) {}
+        export default async function({}) {}
+        export var e;
+        export function g(x, []) {}
+        function h() {}
+    }
+}
+
+mangle: {
+    rename = false
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        const a = 42;
+        export let b, { foo: c } = a;
+        export function f(d, { [b]: e }) {
+            d(e, f);
+        }
+        export default a;
+        export default async function g(x, ...{ [c]: y }) {
+            (await x)(g, y);
+        }
+    }
+    expect: {
+        const t = 42;
+        export let b, { foo: c } = t;
+        export function f(t, { [b]: o }) {
+            t(o, f);
+        }
+        export default t;
+        export default async function e(t, ...{ [c]: o}) {
+            (await t)(e, o);
+        }
+    }
+}
+
+mangle_rename: {
+    rename = true
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        const a = 42;
+        export let b, { foo: c } = a;
+        export function f(d, { [b]: e }) {
+            d(e, f);
+        }
+        export default a;
+        export default async function g(x, ...{ [c]: y }) {
+            (await x)(g, y);
+        }
+    }
+    expect: {
+        const t = 42;
+        export let b, { foo: c } = t;
+        export function f(t, { [b]: o }) {
+            t(o, f);
+        }
+        export default t;
+        export default async function e(t, ...{ [c]: o}) {
+            (await t)(e, o);
+        }
+    }
+}
+
+hoist_exports_1: {
+    options = {
+        hoist_exports: true,
+    }
+    input: {
+        export { a };
+        export var b;
+        export function f() {}
+    }
+    expect: {
+        var b;
+        function f() {}
+        export { a, b, f };
+    }
+}
+
+hoist_exports_2: {
+    options = {
+        evaluate: true,
+        hoist_exports: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        const a = 42;
+        export let bbb, { foo: ccc } = a;
+        export function fff(d, { [bbb]: e }) {
+            d(e, fff);
+        }
+        export default a;
+        export default async function g(x, ...{ [ccc]: y }) {
+            (await x)(g, y);
+        }
+    }
+    expect: {
+        let e, { foo: a } = 42;
+        function f(t, { [e]: o }) {
+            t(o, f);
+        }
+        export default 42;
+        export default async function n(t, ...{ [a]: o }) {
+            (await t)(n, o);
+        };
+        export { e as bbb, a as ccc, f as fff };
+    }
+}
+
+hoist_vars: {
+    options = {
+        hoist_vars: true,
+    }
+    input: {
+        var a;
+        export var b = 42;
+    }
+    expect: {
+        var a;
+        export var b = 42;
+    }
+}
+
+keep_return_values: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        export default function() {
+            return [];
+        }
+        export default function f() {
+            return null;
+        }
+    }
+    expect: {
+        export default function() {
+            return [];
+        }
+        export default function f() {
+            return null;
+        }
+    }
+}
+
+in_use: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        export function f() {}
+        f.prototype.p = 42;
+    }
+    expect: {
+        export function f() {}
+        f.prototype.p = 42;
+    }
+}
+
+in_use_default: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        export default function f() {}
+        f.prototype.p = 42;
+    }
+    expect: {
+        export default function f() {}
+        f.prototype.p = 42;
+    }
+}
+
+single_use: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        export function f() {
+            console.log("PASS");
+        }
+        f();
+    }
+    expect: {
+        export function f() {
+            console.log("PASS");
+        }
+        f();
+    }
+}
+
+single_use_default: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        export default function f() {
+            console.log("PASS");
+        }
+        f();
+    }
+    expect: {
+        export default function f() {
+            console.log("PASS");
+        }
+        f();
+    }
+}
+
+single_use_class: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        export class A {}
+        A.prototype.p = "PASS";
+    }
+    expect: {
+        export class A {}
+        A.prototype.p = "PASS";
+    }
+}
+
+single_use_class_default: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        export default class A {}
+        A.prototype.p = "PASS";
+    }
+    expect: {
+        export default class A {}
+        A.prototype.p = "PASS";
+    }
+}
+
+hoist_funs: {
+    options = {
+        hoist_funs: true,
+    }
+    input: {
+        export function f() {}
+        export default async function* g() {}
+    }
+    expect_exact: "export function f(){}export default async function*g(){}"
+}
+
+issue_4742_join_vars_1: {
+    options = {
+        join_vars: true,
+    }
+    input: {
+        var a = 42;
+        export var a;
+    }
+    expect: {
+        var a = 42;
+        export var a;
+    }
+}
+
+issue_4742_join_vars_2: {
+    options = {
+        join_vars: true,
+    }
+    input: {
+        export var a = "foo";
+        var b;
+        b = "bar";
+    }
+    expect: {
+        export var a = "foo";
+        var b, b = "bar";
+    }
+}
+
+issue_4742_unused_1: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = 42;
+        export var a;
+    }
+    expect: {
+        var a = 42;
+        export var a;
+    }
+}
+
+issue_4742_unused_2: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        export var a = "foo";
+        var a = "bar";
+    }
+    expect: {
+        export var a = "foo";
+        a = "bar";
+    }
+}
+
+issue_4761: {
+    input: {
+        export default "function" == 42;
+    }
+    expect_exact: 'export default"function"==42;'
+}
+
+issue_4766: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = "foo";
+        export var a = "bar";
+    }
+    expect: {
+        var a = "foo";
+        export var a = "bar";
+    }
+}

test/compress/global_defs.js

@@ -2,7 +2,7 @@ must_replace: {
     options = {
         global_defs: {
             D: "foo bar",
-        }
+        },
     }
     input: {
         console.log(D);
@@ -12,6 +12,20 @@ must_replace: {
     }
 }
 
+repeated_nodes: {
+    options = {
+        global_defs: {
+            "@N": "rand()",
+        },
+    }
+    input: {
+        console.log(N, N);
+    }
+    expect: {
+        console.log(rand(), rand());
+    }
+}
+
 keyword: {
     options = {
         global_defs: {
@@ -37,6 +51,7 @@ object: {
                 VALUE: 42,
             },
         },
+        side_effects: true,
         unsafe: true,
     }
     input: {
@@ -140,9 +155,8 @@ 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:129,8]',
+        "WARN: global_defs CONFIG.VALUE redefined [test/compress/global_defs.js:4,22]",
+        "WARN: global_defs CONFIG.VALUE redefined [test/compress/global_defs.js:7,8]",
     ]
 }
 
@@ -174,3 +188,45 @@ issue_1986: {
         console.log(42);
     }
 }
+
+issue_2167: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        global_defs: {
+            "@isDevMode": "function(){}",
+        },
+        passes: 2,
+        side_effects: true,
+    }
+    input: {
+        if (isDevMode()) {
+            greetOverlord();
+        }
+        doWork();
+    }
+    expect: {
+        doWork();
+    }
+}
+
+issue_3217: {
+    options = {
+        collapse_vars: true,
+        global_defs: {
+            "@o": "{fn:function(){var a=42;console.log(a)}}",
+        },
+        inline: true,
+        properties: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        o.fn();
+    }
+    expect: {
+        console.log(42);
+    }
+}

test/compress/hoist_vars.js

@@ -88,3 +88,209 @@ sequences_funs: {
         }
     }
 }
+
+catch_var: {
+    options = {
+        dead_code: true,
+        hoist_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        try {
+            a;
+        } catch (a) {
+            var a = 0;
+            a;
+        }
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+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;
+        }
+    }
+}
+
+issue_4487: {
+    options = {
+        functions: true,
+        hoist_vars: true,
+        keep_fnames: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = function f() {
+            var f = console.log(typeof f);
+        };
+        var b = a();
+    }
+    expect: {
+        function a() {
+            var f = console.log(typeof f);
+        }
+        a();
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4489: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        hoist_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        A = 0;
+        var o = !0 || null;
+        for (var k in o);
+        console.log(k);
+    }
+    expect: {
+        !(A = 0);
+        for (var k in true);
+        console.log(k);
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4517: {
+    options = {
+        collapse_vars: true,
+        hoist_vars: true,
+        join_vars: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            var a = 2;
+            A = a;
+            var b = typeof !1;
+            return A + b;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            var a = 2;
+            A = a;
+            return A + typeof !1;
+        }());
+    }
+    expect_stdout: "2boolean"
+}
+
+issue_4736: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        hoist_vars: true,
+        merge_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        function f() {
+            (function g() {
+                var b = (a = 0, 1 << 30);
+                var c = (a = 0, console.log(b));
+                var d = c;
+            })(f);
+        }
+        f();
+    }
+    expect: {
+        (function() {
+            (function() {
+                0,
+                console.log(1073741824);
+            })();
+        })();
+    }
+    expect_stdout: "1073741824"
+}
+
+issue_4839: {
+    options = {
+        evaluate: true,
+        hoist_vars: true,
+        keep_fargs: false,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = function(a, b) {
+            return b && b;
+        }("foo");
+        for (var k in o)
+            throw "FAIL";
+        console.log("PASS");
+    }
+    expect: {
+        var k, o = void 0;
+        for (k in o)
+            throw "FAIL";
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4859: {
+    options = {
+        evaluate: true,
+        hoist_vars: true,
+        keep_infinity: true,
+        merge_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            var b = (a = 2, 1 / 0), c = 3;
+            var d = a + b;
+            console.log(d);
+            return f;
+        }
+        f();
+    }
+    expect: {
+        (function f(a) {
+            var d = 1 / 0, d = Infinity;
+            console.log(d);
+            return f;
+        })();
+    }
+    expect_stdout: "Infinity"
+}

test/compress/html_comments.js

@@ -1,55 +1,107 @@
 html_comment_in_expression: {
     input: {
-        function f(a, b, x, y) { return a < !--b && x-- > y; }
+        (function(a, b) {
+            console.log(a < !--b && a-- > b, a, b);
+        })(1, 2);
     }
-    expect_exact: "function f(a,b,x,y){return a< !--b&&x-- >y}";
+    expect_exact: "(function(a,b){console.log(a<! --b&&a-- >b,a,b)})(1,2);"
+    expect_stdout: "false 1 1"
 }
 
 html_comment_in_less_than: {
     input: {
-        function f(a, b) { return a < !--b; }
+        (function(a, b, c) {
+            console.log(
+                a < !--b,
+                a < !--b + c,
+                a + b < !--c,
+                a, b, c
+            );
+        })(1, 2, 3);
     }
-    expect_exact: "function f(a,b){return a< !--b}";
+    expect_exact: "(function(a,b,c){console.log(a<! --b,a<! --b+c,a+b<! --c,a,b,c)})(1,2,3);"
+    expect_stdout: "false true false 1 0 2"
 }
 
 html_comment_in_left_shift: {
     input: {
-        function f(a, b) { return a << !--b; }
+        (function(a, b, c) {
+            console.log(
+                a << !--b,
+                a << !--b + c,
+                a + b << !--c,
+                a, b, c
+            );
+        })(1, 2, 3);
     }
-    expect_exact: "function f(a,b){return a<< !--b}";
-}
-
-html_comment_in_right_shift: {
-    input: {
-        function f(a, b) { return a-- >> b; }
-    }
-    expect_exact: "function f(a,b){return a-- >>b}";
-}
-
-html_comment_in_zero_fill_right_shift: {
-    input: {
-        function f(a, b) { return a-- >>> b; }
-    }
-    expect_exact: "function f(a,b){return a-- >>>b}";
+    expect_exact: "(function(a,b,c){console.log(a<<! --b,a<<! --b+c,a+b<<! --c,a,b,c)})(1,2,3);"
+    expect_stdout: "1 16 1 1 0 2"
 }
 
 html_comment_in_greater_than: {
     input: {
-        function f(a, b) { return a-- > b; }
+        (function(a, b, c) {
+            console.log(
+                a-- > b,
+                a-- > b + c,
+                a + b-- > c,
+                a, b, c
+            );
+        })(1, 2, 3);
     }
-    expect_exact: "function f(a,b){return a-- >b}";
+    expect_exact: "(function(a,b,c){console.log(a-- >b,a-- >b+c,a+b-- >c,a,b,c)})(1,2,3);"
+    expect_stdout: "false false false -1 1 3"
 }
 
 html_comment_in_greater_than_or_equal: {
     input: {
-        function f(a, b) { return a-- >= b; }
+        (function(a, b, c) {
+            console.log(
+                a-- >= b,
+                a-- >= b + c,
+                a + b-- >= c,
+                a, b, c
+            );
+        })(1, 2, 3);
     }
-    expect_exact: "function f(a,b){return a-- >=b}";
+    expect_exact: "(function(a,b,c){console.log(a-- >=b,a-- >=b+c,a+b-- >=c,a,b,c)})(1,2,3);"
+    expect_stdout: "false false false -1 1 3"
+}
+
+html_comment_in_right_shift: {
+    input: {
+        (function(a, b, c) {
+            console.log(
+                a-- >> b,
+                a-- >> b + c,
+                a + b-- >> c,
+                a, b, c
+            );
+        })(1, 2, 3);
+    }
+    expect_exact: "(function(a,b,c){console.log(a-- >>b,a-- >>b+c,a+b-- >>c,a,b,c)})(1,2,3);"
+    expect_stdout: "0 0 0 -1 1 3"
+}
+
+html_comment_in_zero_fill_right_shift: {
+    input: {
+        (function(a, b, c) {
+            console.log(
+                a-- >>> b,
+                a-- >>> b + c,
+                a + b-- >>> c,
+                a, b, c
+            );
+        })(1, 2, 3);
+    }
+    expect_exact: "(function(a,b,c){console.log(a-- >>>b,a-- >>>b+c,a+b-- >>>c,a,b,c)})(1,2,3);"
+    expect_stdout: "0 0 0 -1 1 3"
 }
 
 html_comment_in_string_literal: {
     input: {
-        function f() { return "<!--HTML-->comment in<!--string literal-->"; }
+        console.log("<!--HTML-->comment in<!--string literal-->".length);
     }
-    expect_exact: 'function f(){return"\\x3c!--HTML--\\x3ecomment in\\x3c!--string literal--\\x3e"}';
+    expect_exact: 'console.log("\\x3c!--HTML--\\x3ecomment in\\x3c!--string literal--\\x3e".length);'
+    expect_stdout: "42"
 }

test/compress/if_return.js

@@ -1,14 +1,14 @@
 if_return_1: {
     options = {
-        if_return    : true,
-        sequences    : true,
-        conditionals : true,
-        comparisons  : true,
-        evaluate     : true,
-        booleans     : true,
-        unused       : true,
-        side_effects : true,
-        dead_code    : true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        if_return: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function f(x) {
@@ -24,15 +24,15 @@ if_return_1: {
 
 if_return_2: {
     options = {
-        if_return    : true,
-        sequences    : true,
-        conditionals : true,
-        comparisons  : true,
-        evaluate     : true,
-        booleans     : true,
-        unused       : true,
-        side_effects : true,
-        dead_code    : true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        if_return: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function f(x, y) {
@@ -49,15 +49,15 @@ if_return_2: {
 
 if_return_3: {
     options = {
-        if_return    : true,
-        sequences    : true,
-        conditionals : true,
-        comparisons  : true,
-        evaluate     : true,
-        booleans     : true,
-        unused       : true,
-        side_effects : true,
-        dead_code    : true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        if_return: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function f(x) {
@@ -75,15 +75,15 @@ if_return_3: {
 
 if_return_4: {
     options = {
-        if_return    : true,
-        sequences    : true,
-        conditionals : true,
-        comparisons  : true,
-        evaluate     : true,
-        booleans     : true,
-        unused       : true,
-        side_effects : true,
-        dead_code    : true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        if_return: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function f(x, y) {
@@ -100,15 +100,15 @@ if_return_4: {
 
 if_return_5: {
     options = {
-        if_return    : true,
-        sequences    : true,
-        conditionals : true,
-        comparisons  : true,
-        evaluate     : true,
-        booleans     : true,
-        unused       : true,
-        side_effects : true,
-        dead_code    : true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        if_return: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function f() {
@@ -126,15 +126,15 @@ if_return_5: {
 
 if_return_6: {
     options = {
-        if_return    : true,
-        sequences    : true,
-        conditionals : true,
-        comparisons  : true,
-        evaluate     : true,
-        booleans     : true,
-        unused       : true,
-        side_effects : true,
-        dead_code    : true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        if_return: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function f(x) {
@@ -150,15 +150,15 @@ if_return_6: {
 
 if_return_7: {
     options = {
-        if_return    : true,
-        sequences    : true,
-        conditionals : true,
-        comparisons  : true,
-        evaluate     : true,
-        booleans     : true,
-        unused       : true,
-        side_effects : true,
-        dead_code    : true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        if_return: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function f(x) {
@@ -176,10 +176,10 @@ if_return_7: {
 
 if_return_8: {
     options = {
-        if_return:     true,
-        sequences:     true,
-        conditionals:  true,
-        side_effects : true,
+        conditionals: true,
+        if_return: true,
+        sequences: true,
+        side_effects: true,
     }
     input: {
         function f(e) {
@@ -220,15 +220,15 @@ if_return_8: {
 
 issue_1089: {
     options = {
-        if_return    : true,
-        sequences    : true,
-        conditionals : true,
-        comparisons  : true,
-        evaluate     : true,
-        booleans     : true,
-        unused       : true,
-        side_effects : true,
-        dead_code    : true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        if_return: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function x() {
@@ -243,7 +243,7 @@ issue_1089: {
     expect: {
         function x() {
             var f = document.getElementById("fname");
-            if (f.files[0].size > 12345)
+            if (12345 < f.files[0].size)
                 return alert("alert"), f.focus(), !1;
         }
     }
@@ -251,9 +251,9 @@ issue_1089: {
 
 issue_1437: {
     options = {
-        if_return    : true,
-        sequences    : true,
-        conditionals : false
+        conditionals: false,
+        if_return: true,
+        sequences: true,
     }
     input: {
         function x() {
@@ -281,9 +281,9 @@ issue_1437: {
 
 issue_1437_conditionals: {
     options = {
-        conditionals : true,
-        if_return    : true,
-        sequences    : true
+        conditionals: true,
+        if_return: true,
+        sequences: true,
     }
     input: {
         function x() {
@@ -326,3 +326,425 @@ issue_512: {
         }
     }
 }
+
+if_var_return: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        join_vars: true,
+        sequences: true,
+    }
+    input: {
+        function f() {
+            var a;
+            return;
+            var b;
+        }
+        function g() {
+            var a;
+            if (u()) {
+                var b;
+                return v();
+                var c;
+            }
+            var d;
+            if (w()) {
+                var e;
+                return x();
+                var f;
+            } else {
+                var g;
+                y();
+                var h;
+            }
+            var i;
+            z();
+            var j;
+        }
+    }
+    expect: {
+        function f() {
+            var a, b;
+        }
+        function g() {
+            var a, b, c, d, e, f, g, h, i, j;
+            return u() ? v() : w() ? x() : (y(), z(), void 0);
+        }
+    }
+}
+
+if_if_return_return: {
+    options = {
+        conditionals: true,
+        if_return: true,
+    }
+    input: {
+        function f(a, b) {
+            if (a) {
+                if (b)
+                    return b;
+                return;
+            }
+            g();
+        }
+    }
+    expect: {
+        function f(a, b) {
+            if (a)
+                return b || void 0;
+            g();
+        }
+    }
+}
+
+if_body_return_1: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        var c = "PASS";
+        function f(a, b) {
+            if (a) {
+                if (b) throw new Error(c);
+                return 42;
+            }
+            return true;
+        }
+        console.log(f(0, 0));
+        console.log(f(0, 1));
+        console.log(f(1, 0));
+        try {
+            f(1, 1);
+            console.log("FAIL");
+        } catch (e) {
+            console.log(e.message);
+        }
+    }
+    expect: {
+        var c = "PASS";
+        function f(a, b) {
+            if (a) {
+                if (b) throw new Error(c);
+                return 42;
+            }
+            return true;
+        }
+        console.log(f(0, 0));
+        console.log(f(0, 1));
+        console.log(f(1, 0));
+        try {
+            f(1, 1);
+            console.log("FAIL");
+        } catch (e) {
+            console.log(e.message);
+        }
+    }
+    expect_stdout: [
+        "true",
+        "true",
+        "42",
+        "PASS",
+    ]
+}
+
+if_body_return_2: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        var c = "PASS";
+        function f(a, b) {
+            if (0 + a) {
+                if (b) throw new Error(c);
+                return 42;
+            }
+            return true;
+        }
+        console.log(f(0, 0));
+        console.log(f(0, 1));
+        console.log(f(1, 0));
+        try {
+            f(1, 1);
+            console.log("FAIL");
+        } catch (e) {
+            console.log(e.message);
+        }
+    }
+    expect: {
+        var c = "PASS";
+        function f(a, b) {
+            if (0 + a) {
+                if (b) throw new Error(c);
+                return 42;
+            }
+            return true;
+        }
+        console.log(f(0, 0));
+        console.log(f(0, 1));
+        console.log(f(1, 0));
+        try {
+            f(1, 1);
+            console.log("FAIL");
+        } catch (e) {
+            console.log(e.message);
+        }
+    }
+    expect_stdout: [
+        "true",
+        "true",
+        "42",
+        "PASS",
+    ]
+}
+
+if_body_return_3: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        var c = "PASS";
+        function f(a, b) {
+            if (1 == a) {
+                if (b) throw new Error(c);
+                return 42;
+            }
+            return true;
+        }
+        console.log(f(0, 0));
+        console.log(f(0, 1));
+        console.log(f(1, 0));
+        try {
+            f(1, 1);
+            console.log("FAIL");
+        } catch (e) {
+            console.log(e.message);
+        }
+    }
+    expect: {
+        var c = "PASS";
+        function f(a, b) {
+            if (1 != a) return true;
+            if (b) throw new Error(c);
+            return 42;
+        }
+        console.log(f(0, 0));
+        console.log(f(0, 1));
+        console.log(f(1, 0));
+        try {
+            f(1, 1);
+            console.log("FAIL");
+        } catch (e) {
+            console.log(e.message);
+        }
+    }
+    expect_stdout: [
+        "true",
+        "true",
+        "42",
+        "PASS",
+    ]
+}
+
+issue_3600: {
+    options = {
+        if_return: true,
+        inline: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var c = 0;
+        (function() {
+            if ([ ][c++]); else return;
+            return void function() {
+                var b = --b, a = c = 42;
+                return c;
+            }();
+        })();
+        console.log(c);
+    }
+    expect: {
+        var c = 0;
+        (function() {
+            if ([][c++]) b = --b, c = 42;
+            var b;
+        })();
+        console.log(c);
+    }
+    expect_stdout: "1"
+}
+
+iife_if_return_simple: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        inline: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        (function() {
+            if (console)
+                return console.log("PASS");
+            console.log("FAIL");
+        })();
+    }
+    expect: {
+        console ? console.log("PASS") : console.log("FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+nested_if_break: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        for (var i = 0; i < 3; i++)
+            L1: if ("number" == typeof i) {
+                if (0 === i) break L1;
+                console.log(i);
+            }
+    }
+    expect: {
+        for (var i = 0; i < 3; i++)
+            L1: if ("number" == typeof i)
+                if (0 !== i) console.log(i);
+    }
+    expect_stdout: [
+        "1",
+        "2",
+    ]
+}
+
+nested_if_continue: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        join_vars: true,
+        loops: true,
+    }
+    input: {
+        function f(n) {
+            var i = 0;
+            do {
+                if ("number" == typeof n) {
+                    if (0 === n) {
+                        console.log("even", i);
+                        continue;
+                    }
+                    if (1 === n) {
+                        console.log("odd", i);
+                        continue;
+                    }
+                    i++;
+                }
+            } while (0 <= (n -= 2));
+        }
+        f(37);
+        f(42);
+    }
+    expect: {
+        function f(n) {
+            for (var i = 0;
+                "number" == typeof n
+                    && (0 !== n
+                        ? 1 !== n
+                            ? i++
+                            : console.log("odd", i)
+                        : console.log("even", i)),
+                0 <= (n -= 2););
+        }
+        f(37);
+        f(42);
+    }
+    expect_stdout: [
+        "odd 18",
+        "even 21",
+    ]
+}
+
+nested_if_return: {
+    options = {
+        conditionals: true,
+        if_return: true,
+    }
+    input: {
+        function f() {
+            if (A) {
+                if (B)
+                    return B;
+                if (C)
+                    return D;
+                if (E)
+                    return F;
+                if (G)
+                    return H;
+                if (I) {
+                    if (J)
+                        return K;
+                    return;
+                }
+                if (L) {
+                    if (M)
+                        return;
+                    return N;
+                }
+            }
+        }
+    }
+    expect: {
+        function f() {
+            if (A)
+                return B || (C ? D : E ? F : G ? H : I ? J ? K : void 0 : L && !M ? N : void 0);
+        }
+    }
+}
+
+issue_866_1: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        sequences: false,
+    };
+    input: {
+        function f(a) {
+            if (a)
+                return "";
+            console.log(a);
+        }
+    }
+    expect: {
+        function f(a) {
+            if (a)
+                return "";
+            console.log(a);
+        }
+    }
+}
+
+issue_866_2: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        sequences: true,
+    }
+    input: {
+        (function() {
+            if (a)
+                if (b)
+                    c;
+                else
+                    return d;
+        })();
+    }
+    expect: {
+        (function() {
+            if (a) {
+                if (!b)
+                    return d;
+                c;
+            }
+        })();
+    }
+}

test/compress/imports.js

@@ -0,0 +1,211 @@
+nought: {
+    input: {
+        import "foo";
+    }
+    expect_exact: 'import"foo";'
+}
+
+default_only: {
+    input: {
+        import foo from "bar";
+    }
+    expect_exact: 'import foo from"bar";'
+}
+
+all_only: {
+    input: {
+        import * as foo from "bar";
+    }
+    expect_exact: 'import*as foo from"bar";'
+}
+
+keys_only: {
+    input: {
+        import { as as foo, bar, delete as baz } from "moo";
+    }
+    expect_exact: 'import{as as foo,bar,delete as baz}from"moo";'
+}
+
+default_all: {
+    input: {
+        import foo, * as bar from "baz";
+    }
+    expect_exact: 'import foo,*as bar from"baz";'
+}
+
+default_keys: {
+    input: {
+        import foo, { bar } from "baz";
+    }
+    expect_exact: 'import foo,{bar}from"baz";'
+}
+
+dynamic: {
+    input: {
+        (async a => await import(a))("foo").then(bar);
+    }
+    expect_exact: '(async a=>await import(a))("foo").then(bar);'
+}
+
+dynamic_nought: {
+    input: {
+        import(foo);
+    }
+    expect_exact: "import(foo);"
+}
+
+import_meta_1: {
+    input: {
+        console.log(import.meta, import.meta.url);
+    }
+    expect_exact: "console.log(import.meta,import.meta.url);"
+}
+
+import_meta_2: {
+    input: {
+        import.meta.url.split("/").forEach(function(part, index) {
+            console.log(index, part);
+        });
+    }
+    expect_exact: 'import.meta.url.split("/").forEach(function(part,index){console.log(index,part)});'
+}
+
+same_quotes: {
+    beautify = {
+        beautify: true,
+        quote_style: 3,
+    }
+    input: {
+        import 'foo';
+        import "bar";
+    }
+    expect_exact: [
+        "import 'foo';",
+        "",
+        'import "bar";',
+    ]
+}
+
+drop_unused: {
+    options = {
+        imports: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        import a, * as b from "foo";
+        import { c, bar as d } from "baz";
+        console.log(c);
+    }
+    expect: {
+        import "foo";
+        import { c as c } from "baz";
+        console.log(c);
+    }
+}
+
+mangle: {
+    rename = false
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        import foo, { bar } from "baz";
+        consoe.log(moo);
+        import * as moo from "moz";
+    }
+    expect: {
+        import o, { bar as m } from "baz";
+        consoe.log(r);
+        import * as r from "moz";
+    }
+}
+
+rename_mangle: {
+    rename = true
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        import foo, { bar } from "baz";
+        consoe.log(moo);
+        import * as moo from "moz";
+    }
+    expect: {
+        import o, { bar as m } from "baz";
+        consoe.log(r);
+        import * as r from "moz";
+    }
+}
+
+keep_ref: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        import foo from "bar";
+        foo();
+    }
+    expect: {
+        import foo from "bar";
+        foo();
+    }
+}
+
+forbid_merge: {
+    options = {
+        merge_vars: true,
+        toplevel: true,
+    }
+    input: {
+        import A from "foo";
+        export default class extends A {}
+        var f = () => () => {};
+        f();
+        f();
+    }
+    expect: {
+        import A from "foo";
+        export default class extends A {}
+        var f = () => () => {};
+        f();
+        f();
+    }
+}
+
+issue_4708_1: {
+    options = {
+        imports: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        import a from "foo";
+    }
+    expect: {
+        var a;
+        import a from "foo";
+    }
+}
+
+issue_4708_2: {
+    options = {
+        imports: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        console.log(a);
+        import a from "foo";
+    }
+    expect: {
+        var a;
+        console.log(a);
+        import a from "foo";
+    }
+}

test/compress/issue-1034.js

@@ -1,8 +1,17 @@
 non_hoisted_function_after_return: {
     options = {
-        hoist_funs: false, dead_code: true, conditionals: true, comparisons: true,
-        evaluate: true, booleans: true, loops: true, unused: true, keep_fargs: true,
-        if_return: true, join_vars: true, cascade: true, side_effects: true
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        hoist_funs: false,
+        if_return: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function foo(x) {
@@ -21,25 +30,35 @@ non_hoisted_function_after_return: {
     }
     expect: {
         function foo(x) {
-            return x ? bar() : baz();
+            return (x ? bar : baz)();
             function bar() { return 7 }
             function baz() { return 8 }
         }
     }
     expect_warnings: [
-        'WARN: Dropping unreachable code [test/compress/issue-1034.js:11,16]',
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:14,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:17,12]",
-        "WARN: Dropping unused function UnusedFunction [test/compress/issue-1034.js:18,21]"
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:4,16]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:7,16]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:10,12]",
+        "WARN: Dropping unused function UnusedFunction [test/compress/issue-1034.js:11,21]",
     ]
 }
 
 non_hoisted_function_after_return_2a: {
     options = {
-        hoist_funs: false, dead_code: true, conditionals: true, comparisons: true,
-        evaluate: true, booleans: true, loops: true, unused: true, keep_fargs: true,
-        if_return: true, join_vars: true, cascade: true, side_effects: true,
-        collapse_vars: false, passes: 2, warnings: "verbose"
+        booleans: true,
+        collapse_vars: false,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        hoist_funs: false,
+        if_return: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        passes: 2,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function foo(x) {
@@ -65,26 +84,34 @@ non_hoisted_function_after_return_2a: {
         }
     }
     expect_warnings: [
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:48,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:48,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:51,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:51,16]",
-        "WARN: Dropping unused variable a [test/compress/issue-1034.js:48,20]",
-        "WARN: Dropping unused function nope [test/compress/issue-1034.js:55,21]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:53,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:53,12]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:56,12]",
-        "WARN: Dropping unused variable b [test/compress/issue-1034.js:51,20]",
-        "WARN: Dropping unused variable c [test/compress/issue-1034.js:53,16]",
+        "WARN: Dropping initialization in unreachable code [test/compress/issue-1034.js:4,16]",
+        "WARN: Dropping initialization in unreachable code [test/compress/issue-1034.js:7,16]",
+        "WARN: Dropping unused variable a [test/compress/issue-1034.js:4,20]",
+        "WARN: Dropping unused function nope [test/compress/issue-1034.js:11,21]",
+        "INFO: pass 0: last_count: Infinity, count: 35",
+        "WARN: Dropping initialization in unreachable code [test/compress/issue-1034.js:9,12]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:12,12]",
+        "INFO: Dropping unused variable b [test/compress/issue-1034.js:7,20]",
+        "INFO: Dropping unused variable c [test/compress/issue-1034.js:9,16]",
+        "INFO: pass 1: last_count: 35, count: 18",
     ]
 }
 
 non_hoisted_function_after_return_2b: {
     options = {
-        hoist_funs: false, dead_code: true, conditionals: true, comparisons: true,
-        evaluate: true, booleans: true, loops: true, unused: true, keep_fargs: true,
-        if_return: true, join_vars: true, cascade: true, side_effects: true,
-        collapse_vars: false
+        booleans: true,
+        collapse_vars: false,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        hoist_funs: false,
+        if_return: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         function foo(x) {
@@ -108,20 +135,25 @@ non_hoisted_function_after_return_2b: {
         }
     }
     expect_warnings: [
-        // duplicate warnings no longer emitted
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:95,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:95,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:97,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:97,12]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:101,12]",
+        "WARN: Dropping initialization in unreachable code [test/compress/issue-1034.js:8,12]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:12,12]",
     ]
 }
 
 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
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        hoist_funs: false,
+        if_return: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         "use strict";
@@ -143,7 +175,7 @@ non_hoisted_function_after_return_strict: {
     expect: {
         "use strict";
         function foo(x) {
-            return x ? bar() : baz();
+            return (x ? bar : baz)();
             function bar() { return 7 }
             function baz() { return 8 }
         }
@@ -151,19 +183,29 @@ non_hoisted_function_after_return_strict: {
     }
     expect_stdout: "8 7"
     expect_warnings: [
-        'WARN: Dropping unreachable code [test/compress/issue-1034.js:131,16]',
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:134,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:137,12]",
-        "WARN: Dropping unused function UnusedFunction [test/compress/issue-1034.js:138,21]"
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:5,16]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:8,16]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:11,12]",
+        "WARN: Dropping unused function UnusedFunction [test/compress/issue-1034.js:12,21]",
     ]
 }
 
 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"
+        booleans: true,
+        collapse_vars: false,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        hoist_funs: false,
+        if_return: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        passes: 2,
+        side_effects: true,
+        unused: true,
     }
     input: {
         "use strict";
@@ -194,26 +236,34 @@ non_hoisted_function_after_return_2a_strict: {
     }
     expect_stdout: "5 6"
     expect_warnings: [
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:173,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:173,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:176,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:176,16]",
-        "WARN: Dropping unused variable a [test/compress/issue-1034.js:173,20]",
-        "WARN: Dropping unused function nope [test/compress/issue-1034.js:180,21]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:178,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:178,12]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:181,12]",
-        "WARN: Dropping unused variable b [test/compress/issue-1034.js:176,20]",
-        "WARN: Dropping unused variable c [test/compress/issue-1034.js:178,16]",
+        "WARN: Dropping initialization in unreachable code [test/compress/issue-1034.js:5,16]",
+        "WARN: Dropping initialization in unreachable code [test/compress/issue-1034.js:8,16]",
+        "WARN: Dropping unused variable a [test/compress/issue-1034.js:5,20]",
+        "WARN: Dropping unused function nope [test/compress/issue-1034.js:12,21]",
+        "INFO: pass 0: last_count: Infinity, count: 46",
+        "WARN: Dropping initialization in unreachable code [test/compress/issue-1034.js:10,12]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:13,12]",
+        "INFO: Dropping unused variable b [test/compress/issue-1034.js:8,20]",
+        "INFO: Dropping unused variable c [test/compress/issue-1034.js:10,16]",
+        "INFO: pass 1: last_count: 46, 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
+        booleans: true,
+        collapse_vars: false,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        hoist_funs: false,
+        if_return: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         "use strict";
@@ -242,11 +292,7 @@ non_hoisted_function_after_return_2b_strict: {
     }
     expect_stdout: "5 6"
     expect_warnings: [
-        // duplicate warnings no longer emitted
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:225,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:225,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:227,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:227,12]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:231,12]",
+        "WARN: Dropping initialization in unreachable code [test/compress/issue-1034.js:9,12]",
+        "WARN: Dropping unreachable code [test/compress/issue-1034.js:13,12]",
     ]
 }

test/compress/issue-1041.js

@@ -1,8 +1,9 @@
 const_pragma: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
-    };
+    }
 
     input: {
         /** @const */ var goog = goog || {};
@@ -16,8 +17,9 @@ const_pragma: {
 not_const: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
-    };
+    }
 
     input: {
         var goog = goog || {};

test/compress/issue-1052.js

@@ -16,7 +16,7 @@ multiple_functions: {
         ( function() {
             // NOTE: other compression steps will reduce this
             // down to just `window`.
-            if ( window );
+            if ( !window );
             function f() {}
             function g() {}
         } )();
@@ -38,7 +38,7 @@ single_function: {
     }
     expect: {
         ( function() {
-            if ( window );
+            if ( !window );
             function f() {}
         } )();
     }
@@ -67,7 +67,7 @@ deeply_nested: {
             // NOTE: other compression steps will reduce this
             // down to just `window`.
             if ( window )
-                if (document);
+                if ( !document );
             function f() {}
             function g() {}
             function h() {}

test/compress/issue-1105.js

@@ -1,6 +1,6 @@
 with_in_global_scope: {
     options = {
-        unused: true
+        unused: true,
     }
     input: {
         var o = 42;
@@ -18,7 +18,7 @@ with_in_global_scope: {
 }
 with_in_function_scope: {
     options = {
-        unused: true
+        unused: true,
     }
     input: {
         function foo() {
@@ -40,7 +40,7 @@ with_in_function_scope: {
 }
 compress_with_with_in_other_scope: {
     options = {
-        unused: true
+        unused: true,
     }
     input: {
         function foo() {
@@ -69,7 +69,7 @@ compress_with_with_in_other_scope: {
 }
 with_using_existing_variable_outside_scope: {
     options = {
-        unused: true
+        unused: true,
     }
     input: {
         function f() {
@@ -99,7 +99,7 @@ with_using_existing_variable_outside_scope: {
 }
 check_drop_unused_in_peer_function: {
     options = {
-        unused: true
+        unused: true,
     }
     input: {
         function outer() {
@@ -148,52 +148,57 @@ check_drop_unused_in_peer_function: {
 
 Infinity_not_in_with_scope: {
     options = {
-        unused: true
+        unused: true,
     }
     input: {
-        var o = { Infinity: 'oInfinity' };
+        var o = { Infinity: "FAIL" };
         var vInfinity = "Infinity";
         vInfinity = Infinity;
+        console.log(vInfinity);
     }
     expect: {
-        var o = { Infinity: 'oInfinity' }
-        var vInfinity = "Infinity"
-        vInfinity = 1/0
+        var o = { Infinity: "FAIL" };
+        var vInfinity = "Infinity";
+        vInfinity = 1/0;
+        console.log(vInfinity);
     }
+    expect_stdout: "Infinity"
 }
 
 Infinity_in_with_scope: {
     options = {
-        unused: true
+        unused: true,
     }
     input: {
-        var o = { Infinity: 'oInfinity' };
+        var o = { Infinity: "PASS" };
         var vInfinity = "Infinity";
         with (o) { vInfinity = Infinity; }
+        console.log(vInfinity);
     }
     expect: {
-        var o = { Infinity: 'oInfinity' }
-        var vInfinity = "Infinity"
-        with (o) vInfinity = Infinity
+        var o = { Infinity: "PASS" };
+        var vInfinity = "Infinity";
+        with (o) vInfinity = Infinity;
+        console.log(vInfinity);
     }
+    expect_stdout: "PASS"
 }
 
 assorted_Infinity_NaN_undefined_in_with_scope: {
     options = {
-        unused:        true,
-        evaluate:      true,
-        dead_code:     true,
-        conditionals:  true,
-        comparisons:   true,
-        booleans:      true,
-        hoist_funs:    true,
-        keep_fargs:    true,
-        if_return:     true,
-        join_vars:     true,
-        cascade:       true,
-        side_effects:  true,
-        sequences:     false,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        hoist_funs: true,
+        if_return: true,
+        join_vars: true,
+        keep_fargs: true,
         keep_infinity: false,
+        sequences: false,
+        side_effects: true,
+        unused: true,
     }
     input: {
         var f = console.log;
@@ -243,20 +248,19 @@ assorted_Infinity_NaN_undefined_in_with_scope: {
 
 assorted_Infinity_NaN_undefined_in_with_scope_keep_infinity: {
     options = {
-        unused:        true,
-        evaluate:      true,
-        dead_code:     true,
-        conditionals:  true,
-        comparisons:   true,
-        booleans:      true,
-        hoist_funs:    true,
-        keep_fargs:    true,
-        if_return:     true,
-        join_vars:     true,
-        cascade:       true,
-        side_effects:  true,
-        sequences:     false,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        hoist_funs: true,
+        if_return: true,
+        join_vars: true,
+        keep_fargs: true,
         keep_infinity: true,
+        sequences: false,
+        side_effects: true,
+        unused: true,
     }
     input: {
         var f = console.log;

test/compress/issue-12.js

@@ -1,58 +1,78 @@
 keep_name_of_getter: {
-    options = { unused: true };
-    input: { a = { get foo () {} } }
-    expect: { a = { get foo () {} } }
+    options = {
+        unused: true,
+    }
+    input: {
+        a = {
+            get foo() {},
+        };
+    }
+    expect: {
+        a = {
+            get foo() {},
+        };
+    }
 }
 
 keep_name_of_setter: {
-    options = { unused: true };
-    input: { a = { set foo () {} } }
-    expect: { a = { set foo () {} } }
+    options = {
+        unused: true,
+    }
+    input: {
+        a = {
+            set foo(v) {},
+        };
+    }
+    expect: {
+        a = {
+            set foo(v) {},
+        };
+    }
 }
 
 setter_with_operator_keys: {
     input: {
-        var tokenCodes  = {
-            get instanceof(){
+        var tokenCodes = {
+            get instanceof() {
                 return test0;
             },
-            set instanceof(value){
+            set instanceof(value) {
                 test0 = value;
             },
-            set typeof(value){
+            set typeof(value) {
                 test1 = value;
             },
-            get typeof(){
+            get typeof() {
                 return test1;
             },
-            set else(value){
+            set else(value) {
                 test2 = value;
             },
-            get else(){
+            get else() {
                 return test2;
-            }
+            },
         };
     }
     expect: {
-        var tokenCodes  = {
-            get instanceof(){
+        var tokenCodes = {
+            get instanceof() {
                 return test0;
             },
-            set instanceof(value){
+            set instanceof(value) {
                 test0 = value;
             },
-            set typeof(value){
+            set typeof(value) {
                 test1 = value;
             },
-            get typeof(){
+            get typeof() {
                 return test1;
             },
-            set else(value){
+            set else(value) {
                 test2 = value;
             },
-            get else(){
+            get else() {
                 return test2;
-            }
+            },
         };
     }
-}
+}

test/compress/issue-1202.js

@@ -1,10 +1,10 @@
 mangle_keep_fnames_false: {
     options = {
-        keep_fnames : true,
-        keep_fargs  : true,
+        keep_fargs: true,
+        keep_fnames: true,
     }
     mangle = {
-        keep_fnames : false,
+        keep_fnames: false,
     }
     input: {
         "use strict";
@@ -26,11 +26,11 @@ mangle_keep_fnames_false: {
 
 mangle_keep_fnames_true: {
     options = {
-        keep_fnames : true,
-        keep_fargs  : true,
+        keep_fargs: true,
+        keep_fnames: true,
     }
     mangle = {
-        keep_fnames : true,
+        keep_fnames: true,
     }
     input: {
         "use strict";

test/compress/issue-1261.js

@@ -1,15 +1,15 @@
 pure_function_calls: {
     options = {
-        evaluate     : true,
-        conditionals : true,
-        comparisons  : true,
-        side_effects : true,
-        booleans     : true,
-        unused       : true,
-        if_return    : true,
-        join_vars    : true,
-        cascade      : true,
-        negate_iife  : true,
+        annotations: true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        evaluate: true,
+        if_return: true,
+        join_vars: true,
+        negate_iife: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         // pure top-level IIFE will be dropped
@@ -49,29 +49,29 @@ pure_function_calls: {
         a.b(), f.g();
     }
     expect_warnings: [
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:17,8]",
-        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:17,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:30,37]",
-        "WARN: Dropping unused variable iife2 [test/compress/issue-1261.js:30,16]",
-        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:28,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:38,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:39,31]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:3,8]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:3,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:16,37]",
+        "WARN: Dropping unused variable iife2 [test/compress/issue-1261.js:16,16]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:14,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:24,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:25,31]",
     ]
 }
 
 pure_function_calls_toplevel: {
     options = {
-        evaluate     : true,
-        conditionals : true,
-        comparisons  : true,
-        side_effects : true,
-        booleans     : true,
-        unused       : true,
-        if_return    : true,
-        join_vars    : true,
-        cascade      : true,
-        negate_iife  : true,
-        toplevel     : true,
+        annotations: true,
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        evaluate: true,
+        if_return: true,
+        join_vars: true,
+        negate_iife: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
     }
     input: {
         // pure top-level IIFE will be dropped
@@ -96,6 +96,13 @@ 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();
@@ -105,20 +112,23 @@ pure_function_calls_toplevel: {
         a.b(), f.g();
     }
     expect_warnings: [
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:79,8]",
-        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:79,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:92,37]",
-        "WARN: Dropping unused variable iife2 [test/compress/issue-1261.js:92,16]",
-        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:90,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:100,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:101,31]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:84,33]",
-        "WARN: Dropping unused variable iife1 [test/compress/issue-1261.js:84,12]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:3,8]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:3,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:16,37]",
+        "WARN: Dropping unused variable iife2 [test/compress/issue-1261.js:16,16]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:14,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:31,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:32,31]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:8,33]",
+        "WARN: Dropping unused variable iife1 [test/compress/issue-1261.js:8,12]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:24,45]",
+        "WARN: Dropping unused variable MyClass [test/compress/issue-1261.js:24,12]",
     ]
 }
 
 should_warn: {
     options = {
+        annotations: true,
         booleans: true,
         conditionals: true,
         evaluate: true,
@@ -148,29 +158,29 @@ should_warn: {
         baz();
     }
     expect_warnings: [
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:128,61]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:128,23]",
-        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:128,23]",
-        "WARN: Boolean || always true [test/compress/issue-1261.js:129,23]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:129,23]",
-        "WARN: Condition always true [test/compress/issue-1261.js:129,23]",
-        "WARN: Condition left of || always true [test/compress/issue-1261.js:130,8]",
-        "WARN: Condition always true [test/compress/issue-1261.js:130,8]",
-        "WARN: Boolean && always false [test/compress/issue-1261.js:131,23]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:131,23]",
-        "WARN: Condition always false [test/compress/issue-1261.js:131,23]",
-        "WARN: Condition left of && always false [test/compress/issue-1261.js:132,8]",
-        "WARN: Condition always false [test/compress/issue-1261.js:132,8]",
-        "WARN: + in boolean context always true [test/compress/issue-1261.js:133,23]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:133,23]",
-        "WARN: Condition always true [test/compress/issue-1261.js:133,23]",
-        "WARN: + in boolean context always true [test/compress/issue-1261.js:134,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:134,31]",
-        "WARN: Condition always true [test/compress/issue-1261.js:134,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:135,23]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:136,24]",
-        "WARN: Condition always true [test/compress/issue-1261.js:136,8]",
-        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:137,31]",
-        "WARN: Condition always false [test/compress/issue-1261.js:137,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:1,61]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:1,23]",
+        "WARN: Dropping side-effect-free statement [test/compress/issue-1261.js:1,23]",
+        "WARN: Boolean || always true [test/compress/issue-1261.js:2,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:2,23]",
+        "WARN: Condition always true [test/compress/issue-1261.js:2,23]",
+        "WARN: Condition left of || always true [test/compress/issue-1261.js:3,8]",
+        "WARN: Condition always true [test/compress/issue-1261.js:3,8]",
+        "WARN: Boolean && always false [test/compress/issue-1261.js:4,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:4,23]",
+        "WARN: Condition always false [test/compress/issue-1261.js:4,23]",
+        "WARN: Condition left of && always false [test/compress/issue-1261.js:5,8]",
+        "WARN: Condition always false [test/compress/issue-1261.js:5,8]",
+        "WARN: + in boolean context always true [test/compress/issue-1261.js:6,23]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:6,23]",
+        "WARN: Condition always true [test/compress/issue-1261.js:6,23]",
+        "WARN: + in boolean context always true [test/compress/issue-1261.js:7,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:7,31]",
+        "WARN: Condition always true [test/compress/issue-1261.js:7,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:8,23]",
+        "WARN: Condition always true [test/compress/issue-1261.js:9,8]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:9,24]",
+        "WARN: Dropping __PURE__ call [test/compress/issue-1261.js:10,31]",
+        "WARN: Condition always false [test/compress/issue-1261.js:10,8]",
     ]
 }

test/compress/issue-1275.js

@@ -1,17 +1,16 @@
 string_plus_optimization: {
     options = {
-        side_effects  : true,
-        evaluate      : true,
-        conditionals  : true,
-        comparisons   : true,
-        dead_code     : true,
-        booleans      : true,
-        unused        : true,
-        if_return     : true,
-        join_vars     : true,
-        cascade       : true,
-        hoist_funs    : true,
-    };
+        booleans: true,
+        comparisons: true,
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        hoist_funs: true,
+        if_return: true,
+        join_vars: true,
+        side_effects: true,
+        unused: true,
+    }
     input: {
         function foo(anything) {
             function throwing_function() {

test/compress/issue-1321.js

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

test/compress/issue-143.js

@@ -15,7 +15,7 @@
 tranformation_sort_order_equal: {
     options = {
         comparisons: true,
-    };
+    }
 
     input: { (a = parseInt('100')) == a }
     expect: { (a = parseInt('100')) == a }
@@ -24,7 +24,7 @@ tranformation_sort_order_equal: {
 tranformation_sort_order_unequal: {
     options = {
         comparisons: true,
-    };
+    }
 
     input: { (a = parseInt('100')) != a }
     expect: { (a = parseInt('100')) != a }
@@ -33,7 +33,7 @@ tranformation_sort_order_unequal: {
 tranformation_sort_order_lesser_or_equal: {
     options = {
         comparisons: true,
-    };
+    }
 
     input: { (a = parseInt('100')) <= a }
     expect: { (a = parseInt('100')) <= a }
@@ -41,7 +41,7 @@ tranformation_sort_order_lesser_or_equal: {
 tranformation_sort_order_greater_or_equal: {
     options = {
         comparisons: true,
-    };
+    }
 
     input: { (a = parseInt('100')) >= a }
     expect: { (a = parseInt('100')) >= a }

test/compress/issue-1431.js

@@ -1,6 +1,6 @@
 level_zero: {
     options = {
-        keep_fnames: true
+        keep_fnames: true,
     }
     mangle = {
         keep_fnames: true
@@ -29,7 +29,7 @@ level_zero: {
 
 level_one: {
     options = {
-        keep_fnames: true
+        keep_fnames: true,
     }
     mangle = {
         keep_fnames: true
@@ -58,7 +58,7 @@ level_one: {
 
 level_two: {
     options = {
-        keep_fnames: true
+        keep_fnames: true,
     }
     mangle = {
         keep_fnames: true
@@ -97,7 +97,7 @@ level_two: {
 
 level_three: {
     options = {
-        keep_fnames: true
+        keep_fnames: true,
     }
     mangle = {
         keep_fnames: true

test/compress/issue-1443.js

@@ -4,7 +4,7 @@ unsafe_undefined: {
     options = {
         conditionals: true,
         if_return: true,
-        unsafe: true
+        unsafe_undefined: true,
     }
     mangle = {}
     input: {
@@ -30,7 +30,7 @@ keep_fnames: {
     options = {
         conditionals: true,
         if_return: true,
-        unsafe: true
+        unsafe_undefined: true,
     }
     mangle = {
         keep_fnames: true

test/compress/issue-1446.js

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

test/compress/issue-1447.js

@@ -22,18 +22,17 @@ else_with_empty_statement: {
 
 conditional_false_stray_else_in_loop: {
     options = {
-        evaluate     : true,
-        comparisons  : true,
-        booleans     : true,
-        unused       : true,
-        loops        : true,
-        side_effects : true,
-        dead_code    : true,
-        hoist_vars   : true,
-        join_vars    : true,
-        if_return    : true,
-        cascade      : true,
-        conditionals : false,
+        booleans: true,
+        comparisons: true,
+        conditionals: false,
+        dead_code: true,
+        evaluate: true,
+        hoist_vars: true,
+        if_return: true,
+        join_vars: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
     }
     input: {
         for (var i = 1; i <= 4; ++i) {

test/compress/issue-1588.js

@@ -61,7 +61,7 @@ unsafe_undefined: {
     options = {
         conditionals: true,
         if_return: true,
-        unsafe: true,
+        unsafe_undefined: true,
     }
     mangle = {}
     input: {

test/compress/issue-1609.js

@@ -2,6 +2,7 @@ chained_evaluation_1: {
     options = {
         collapse_vars: true,
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -28,6 +29,7 @@ chained_evaluation_2: {
     options = {
         collapse_vars: true,
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -50,3 +52,30 @@ chained_evaluation_2: {
         })();
     }
 }
+
+chained_evaluation_3: {
+    options = {
+        collapse_vars: true,
+        evaluate: 10,
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var a = "long piece of string";
+            (function() {
+                var b = a, c;
+                c = f(b);
+                c.bar = b;
+            })();
+        })();
+    }
+    expect: {
+        (function() {
+            (function() {
+                f("long piece of string").bar = "long piece of string";
+            })();
+        })();
+    }
+}

test/compress/issue-1639.js

@@ -1,8 +1,7 @@
-
 issue_1639_1: {
     options = {
         booleans: true,
-        cascade: true,
+        collapse_vars: true,
         conditionals: true,
         evaluate: true,
         join_vars: true,
@@ -12,7 +11,6 @@ issue_1639_1: {
     }
     input: {
         var a = 100, b = 10;
-
         var L1 = 5;
         while (--L1 > 0) {
             if ((--b), false) {
@@ -21,21 +19,21 @@ issue_1639_1: {
                 }
             }
         }
-
         console.log(a, b);
     }
     expect: {
-        for (var a = 100, b = 10, L1 = 5; --L1 > 0;)
-            if (--b, !1) var ignore = 0;
+        for (var a = 100, b = 10, L1 = 5, ignore; --L1 > 0;) {
+            --b;
+        }
         console.log(a, b);
     }
-    expect_stdout: true
+    expect_stdout: "100 6"
 }
 
 issue_1639_2: {
     options = {
         booleans: true,
-        cascade: true,
+        collapse_vars: true,
         conditionals: true,
         evaluate: true,
         join_vars: true,
@@ -44,14 +42,12 @@ issue_1639_2: {
     }
     input: {
         var a = 100, b = 10;
-
         function f19() {
             if (++a, false)
                 if (a)
                     if (++a);
         }
         f19();
-
         console.log(a, b);
     }
     expect: {
@@ -62,13 +58,13 @@ issue_1639_2: {
         f19(),
         console.log(a, b);
     }
-    expect_stdout: true
+    expect_stdout: "101 10"
 }
 
 issue_1639_3: {
     options = {
         booleans: true,
-        cascade: true,
+        collapse_vars: true,
         conditionals: true,
         evaluate: true,
         sequences: true,
@@ -84,5 +80,5 @@ issue_1639_3: {
         a++,
         console.log(a, b);
     }
-    expect_stdout: true
+    expect_stdout: "101 10"
 }

test/compress/issue-1656.js

@@ -1,7 +1,6 @@
 f7: {
     options = {
         booleans: true,
-        cascade: true,
         collapse_vars: true,
         comparisons: true,
         conditionals: true,
@@ -15,6 +14,7 @@ f7: {
         negate_iife: true,
         passes: 3,
         properties: true,
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         side_effects: true,
@@ -35,11 +35,7 @@ f7: {
         console.log(a, b);
     }
     expect_exact: [
-        "var b = 10;",
-        "",
-        "!function() {",
-        "    for (;b = 100, !1; ) ;",
-        "}(), console.log(100, b);",
+        "console.log(100, 100);",
     ]
-    expect_stdout: true
+    expect_stdout: "100 100"
 }

test/compress/issue-1673.js

@@ -1,5 +1,6 @@
 side_effects_catch: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -34,6 +35,7 @@ side_effects_catch: {
 
 side_effects_else: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -62,6 +64,7 @@ side_effects_else: {
 
 side_effects_finally: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -98,6 +101,7 @@ side_effects_finally: {
 
 side_effects_label: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -130,6 +134,7 @@ side_effects_label: {
 
 side_effects_switch: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,

test/compress/issue-1704.js

@@ -104,7 +104,7 @@ mangle_catch_toplevel: {
         }
         console.log(a);
     }
-    expect_exact: 'var o="FAIL";try{throw 1}catch(c){o="PASS"}console.log(o);'
+    expect_exact: 'var c="FAIL";try{throw 1}catch(o){c="PASS"}console.log(c);'
     expect_stdout: "PASS"
 }
 
@@ -148,7 +148,7 @@ mangle_catch_var_toplevel: {
         }
         console.log(a);
     }
-    expect_exact: 'var o="FAIL";try{throw 1}catch(r){var o="PASS"}console.log(o);'
+    expect_exact: 'var r="FAIL";try{throw 1}catch(o){var r="PASS"}console.log(r);'
     expect_stdout: "PASS"
 }
 
@@ -345,3 +345,95 @@ mangle_catch_redef_2_ie8_toplevel: {
     expect_exact: 'try{throw"FAIL1"}catch(o){var o="FAIL2"}console.log(o);'
     expect_stdout: "undefined"
 }
+
+mangle_catch_redef_3: {
+    mangle = {
+        ie8: false,
+        toplevel: false,
+    }
+    input: {
+        var o = "PASS";
+        try {
+            throw 0;
+        } catch (o) {
+            (function() {
+                function f() {
+                    o = "FAIL";
+                }
+                f(), f();
+            })();
+        }
+        console.log(o);
+    }
+    expect_exact: 'var o="PASS";try{throw 0}catch(o){(function(){function c(){o="FAIL"}c(),c()})()}console.log(o);'
+    expect_stdout: true
+}
+
+mangle_catch_redef_3_toplevel: {
+    mangle = {
+        ie8: false,
+        toplevel: true,
+    }
+    input: {
+        var o = "PASS";
+        try {
+            throw 0;
+        } catch (o) {
+            (function() {
+                function f() {
+                    o = "FAIL";
+                }
+                f(), f();
+            })();
+        }
+        console.log(o);
+    }
+    expect_exact: 'var c="PASS";try{throw 0}catch(c){(function(){function o(){c="FAIL"}o(),o()})()}console.log(c);'
+    expect_stdout: true
+}
+
+mangle_catch_redef_3_ie8: {
+    mangle = {
+        ie8: true,
+        toplevel: false,
+    }
+    input: {
+        var o = "PASS";
+        try {
+            throw 0;
+        } catch (o) {
+            (function() {
+                function f() {
+                    o = "FAIL";
+                }
+                f(), f();
+            })();
+        }
+        console.log(o);
+    }
+    expect_exact: 'var o="PASS";try{throw 0}catch(o){(function(){function c(){o="FAIL"}c(),c()})()}console.log(o);'
+    expect_stdout: true
+}
+
+mangle_catch_redef_3_ie8_toplevel: {
+    mangle = {
+        ie8: true,
+        toplevel: true,
+    }
+    input: {
+        var o = "PASS";
+        try {
+            throw 0;
+        } catch (o) {
+            (function() {
+                function f() {
+                    o = "FAIL";
+                }
+                f(), f();
+            })();
+        }
+        console.log(o);
+    }
+    expect_exact: 'var c="PASS";try{throw 0}catch(c){(function(){function o(){c="FAIL"}o(),o()})()}console.log(c);'
+    expect_stdout: true
+}

test/compress/issue-1733.js

@@ -15,7 +15,7 @@ function_iife_catch: {
         }
         f();
     }
-    expect_exact: "function f(o){!function(){try{throw 0}catch(c){var o=1;console.log(c,o)}}()}f();"
+    expect_exact: "function f(o){!function(){try{throw 0}catch(o){var c=1;console.log(o,c)}}()}f();"
     expect_stdout: "0 1"
 }
 
@@ -36,7 +36,7 @@ function_iife_catch_ie8: {
         }
         f();
     }
-    expect_exact: "function f(o){!function(){try{throw 0}catch(o){var c=1;console.log(o,c)}}()}f();"
+    expect_exact: "function f(c){!function(){try{throw 0}catch(c){var o=1;console.log(c,o)}}()}f();"
     expect_stdout: "0 1"
 }
 
@@ -61,7 +61,7 @@ function_catch_catch: {
         }
         f();
     }
-    expect_exact: "var o=0;function f(){try{throw 1}catch(c){try{throw 2}catch(o){var o=3;console.log(o)}}console.log(o)}f();"
+    expect_exact: "var o=0;function f(){try{throw 1}catch(o){try{throw 2}catch(c){var c=3;console.log(c)}}console.log(c)}f();"
     expect_stdout: [
         "3",
         "undefined",

test/compress/issue-1750.js

@@ -7,7 +7,7 @@ case_1: {
     input: {
         var a = 0, b = 1;
         switch (true) {
-          case a, true:
+          case a || true:
           default:
             b = 2;
           case true:
@@ -17,7 +17,7 @@ case_1: {
     expect: {
         var a = 0, b = 1;
         switch (true) {
-          case a, true:
+          case a || true:
             b = 2;
         }
         console.log(a, b);

test/compress/issue-1770.js

@@ -1,5 +1,7 @@
 mangle_props: {
-    mangle_props = {}
+    mangle = {
+        properties: true,
+    }
     input: {
         var obj = {
             undefined: 1,
@@ -44,7 +46,7 @@ mangle_props: {
             obj[1/0],
             obj["Infinity"],
             obj[-1/0],
-            obj[-1/0],
+            obj[-(1/0)],
             obj["-Infinity"],
             obj[null],
             obj["null"]
@@ -54,10 +56,12 @@ mangle_props: {
 }
 
 numeric_literal: {
+    mangle = {
+        properties: true,
+    }
     beautify = {
         beautify: true,
     }
-    mangle_props = {}
     input: {
         var obj = {
             0: 0,
@@ -80,19 +84,19 @@ numeric_literal: {
         '    0: 0,',
         '    "-0": 1,',
         '    42: 2,',
-        '    "42": 3,',
+        '    42: 3,',
         '    37: 4,',
-        '    a: 5,',
+        '    o: 5,',
         '    1e42: 6,',
         '    b: 7,',
-        '    "1e+42": 8',
+        '    1e42: 8',
         '};',
         '',
         'console.log(obj[-0], obj[-""], obj["-0"]);',
         '',
         'console.log(obj[42], obj["42"]);',
         '',
-        'console.log(obj[37], obj["a"], obj[37], obj["37"]);',
+        'console.log(obj[37], obj["o"], obj[37], obj["37"]);',
         '',
         'console.log(obj[1e42], obj["b"], obj["1e+42"]);',
     ]
@@ -105,7 +109,9 @@ numeric_literal: {
 }
 
 identifier: {
-    mangle_props = {}
+    mangle = {
+        properties: true,
+    }
     input: {
         var obj = {
             abstract: 1,
@@ -173,32 +179,32 @@ identifier: {
     }
     expect: {
         var obj = {
-            a: 1,
-            b: 2,
-            c: 3,
-            d: 4,
-            e: 5,
-            f: 6,
-            g: 7,
-            h: 8,
-            i: 9,
-            j: 10,
-            k: 11,
-            l: 12,
-            m: 13,
-            n: 14,
-            o: 15,
-            p: 16,
-            q: 17,
-            r: 18,
-            s: 19,
-            t: 20,
-            u: 21,
-            v: 22,
-            w: 23,
-            x: 24,
-            y: 25,
-            z: 26,
+            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,
@@ -229,11 +235,11 @@ identifier: {
             Z: 54,
             $: 55,
             _: 56,
-            aa: 57,
-            ba: 58,
-            ca: 59,
-            da: 60,
-            ea: 61,
+            ee: 57,
+            te: 58,
+            ne: 59,
+            ae: 60,
+            ie: 61,
         };
     }
 }

test/compress/issue-1787.js

@@ -1,6 +1,8 @@
 unary_prefix: {
     options = {
         evaluate: true,
+        inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }

test/compress/issue-1833.js

@@ -1,6 +1,7 @@
 iife_for: {
     options = {
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -26,6 +27,7 @@ iife_for: {
 iife_for_in: {
     options = {
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -51,6 +53,7 @@ iife_for_in: {
 iife_do: {
     options = {
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -80,6 +83,7 @@ iife_do: {
 iife_while: {
     options = {
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -121,8 +125,8 @@ label_do: {
 
 label_while: {
     options = {
-        evaluate: true,
         dead_code: true,
+        evaluate: true,
         loops: true,
     }
     input: {
@@ -130,5 +134,5 @@ label_while: {
             L: while (0) continue L;
         }
     }
-    expect_exact: "function f(){L:;}"
+    expect_exact: "function f(){L:0}"
 }

test/compress/issue-208.js

@@ -1,6 +1,8 @@
 do_not_update_lhs: {
     options = {
-        global_defs: { DEBUG: 0 }
+        global_defs: {
+            DEBUG: 0,
+        },
     }
     input: {
         DEBUG++;
@@ -16,7 +18,9 @@ do_not_update_lhs: {
 
 do_update_rhs: {
     options = {
-        global_defs: { DEBUG: 0 }
+        global_defs: {
+            DEBUG: 0,
+        },
     }
     input: {
         MY_DEBUG = DEBUG;
@@ -35,7 +39,7 @@ mixed: {
             DEBUG: 0,
             ENV: 1,
             FOO: 2,
-        }
+        },
     }
     input: {
         var ENV = 3;
@@ -60,11 +64,11 @@ mixed: {
         x = 0;
     }
     expect_warnings: [
-        'WARN: global_defs ENV redefined [test/compress/issue-208.js:41,12]',
-        'WARN: global_defs FOO redefined [test/compress/issue-208.js:42,12]',
-        'WARN: global_defs FOO redefined [test/compress/issue-208.js:44,10]',
-        'WARN: global_defs DEBUG redefined [test/compress/issue-208.js:45,8]',
-        'WARN: global_defs DEBUG redefined [test/compress/issue-208.js:46,8]',
-        'WARN: global_defs DEBUG redefined [test/compress/issue-208.js:47,8]',
+        "WARN: global_defs ENV redefined [test/compress/issue-208.js:1,12]",
+        "WARN: global_defs FOO redefined [test/compress/issue-208.js:2,12]",
+        "WARN: global_defs FOO redefined [test/compress/issue-208.js:4,10]",
+        "WARN: global_defs DEBUG redefined [test/compress/issue-208.js:5,8]",
+        "WARN: global_defs DEBUG redefined [test/compress/issue-208.js:6,8]",
+        "WARN: global_defs DEBUG redefined [test/compress/issue-208.js:7,8]",
     ]
 }

test/compress/issue-22.js

@@ -1,5 +1,7 @@
 return_with_no_value_in_if_body: {
-    options = { conditionals: true };
+    options = {
+        conditionals: true,
+    }
     input: {
         function foo(bar) {
             if (bar) {

test/compress/issue-2652.js

@@ -0,0 +1,33 @@
+insert_semicolon: {
+    beautify = {
+        beautify: true,
+        comments: "all",
+    }
+    input: {
+        var a
+        /* foo */ var b
+    }
+    expect_exact: [
+        "var a",
+        "/* foo */;",
+        "",
+        "var b;",
+    ]
+}
+
+unary_postfix: {
+    beautify = {
+        beautify: true,
+        comments: "all",
+    }
+    input: {
+        a
+        /* foo */++b
+    }
+    expect_exact: [
+        "a",
+        "/* foo */;",
+        "",
+        "++b;",
+    ]
+}

test/compress/issue-267.js

@@ -1,5 +1,7 @@
 issue_267: {
-    options = { comparisons: true };
+    options = {
+        comparisons: true,
+    }
     input: {
         x = a % b / b * c * 2;
         x = a % b * 2

test/compress/issue-269.js

@@ -1,66 +1,111 @@
 issue_269_1: {
-	options = {unsafe: true};
-	input: {
-		f(
-			String(x),
-			Number(x),
-			Boolean(x),
+    options = {
+        unsafe: true,
+    }
+    input: {
+        var x = {};
+        console.log(
+            String(x),
+            Number(x),
+            Boolean(x),
 
-			String(),
-			Number(),
-			Boolean()
-		);
-	}
-	expect: {
-		f(
-			x + '', +x, !!x,
-			'', 0, false
-		);
-	}
+            String(),
+            Number(),
+            Boolean()
+        );
+    }
+    expect: {
+        var x = {};
+        console.log(
+            "" + x, +("" + x), !!x,
+            "", 0, false
+        );
+    }
+    expect_stdout: true
 }
 
 issue_269_dangers: {
-	options = {unsafe: true};
-	input: {
-		f(
-			String(x, x),
-			Number(x, x),
-			Boolean(x, x)
-		);
-	}
-	expect: {
-		f(String(x, x), Number(x, x), Boolean(x, x));
-	}
+    options = {
+        unsafe: true,
+    }
+    input: {
+        var x = {};
+        console.log(
+            String(x, x),
+            Number(x, x),
+            Boolean(x, x)
+        );
+    }
+    expect: {
+        var x = {};
+        console.log(String(x, x), Number(x, x), Boolean(x, x));
+    }
+    expect_stdout: true
 }
 
 issue_269_in_scope: {
-	options = {unsafe: true};
-	input: {
-		var String, Number, Boolean;
-		f(
-			String(x),
-			Number(x, x),
-			Boolean(x)
-		);
-	}
-	expect: {
-		var String, Number, Boolean;
-		f(String(x), Number(x, x), Boolean(x));
-	}
+    options = {
+        unsafe: true,
+    }
+    input: {
+        var String, Number, Boolean;
+        var x = {};
+        console.log(
+            String(x),
+            Number(x, x),
+            Boolean(x)
+        );
+    }
+    expect: {
+        var String, Number, Boolean;
+        var x = {};
+        console.log(String(x), Number(x, x), Boolean(x));
+    }
+    expect_stdout: true
 }
 
 strings_concat: {
-	options = {unsafe: true};
-	input: {
-		f(
-			String(x + 'str'),
-			String('str' + x)
-		);
-	}
-	expect: {
-		f(
-			x + 'str',
-			'str' + x
-		);
-	}
+    options = {
+        strings: true,
+        unsafe: true,
+    }
+    input: {
+        var x = {};
+        console.log(
+            String(x + "str"),
+            String("str" + x)
+        );
+    }
+    expect: {
+        var x = {};
+        console.log(
+            x + "str",
+            "str" + x
+        );
+    }
+    expect_stdout: true
+}
+
+regexp: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        RegExp("foo");
+        RegExp("bar", "ig");
+        RegExp(foo);
+        RegExp("bar", ig);
+        RegExp("should", "fail");
+    }
+    expect: {
+        /foo/;
+        /bar/ig;
+        RegExp(foo);
+        RegExp("bar", ig);
+        RegExp("should", "fail");
+    }
+    expect_warnings: [
+        'WARN: Error converting RegExp("should","fail") [test/compress/issue-269.js:5,8]',
+    ]
 }

test/compress/issue-2719.js

@@ -0,0 +1,32 @@
+warn: {
+    options = {
+        evaluate: true,
+        inline: true,
+        passes: 2,
+        properties: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            return g();
+        }
+        function g() {
+            return g["call" + "er"].arguments;
+        }
+        // 3
+        console.log(f(1, 2, 3).length);
+    }
+    expect: {
+        // TypeError: Cannot read property 'arguments' of null
+        console.log(function g() {
+            return g.caller.arguments;
+        }().length);
+    }
+    expect_warnings: [
+        "WARN: Function.prototype.arguments not supported [test/compress/issue-2719.js:5,19]",
+        "WARN: Function.prototype.caller not supported [test/compress/issue-2719.js:5,19]",
+    ]
+}

test/compress/issue-281.js

@@ -0,0 +1,508 @@
+collapse_vars_constants: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        reduce_funcs: 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_funcs: 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_funcs: 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_funcs: 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_funcs: true,
+        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 = {
+        annotations: true,
+        inline: true,
+        side_effects: true,
+    }
+    input: {
+        /*@__PURE__*/(function() {
+            console.log("hello");
+        }());
+    }
+    expect_exact: ""
+}
+
+pure_annotation_2: {
+    options = {
+        annotations: true,
+        collapse_vars: true,
+        inline: true,
+        side_effects: true,
+    }
+    input: {
+        /*@__PURE__*/(function(n) {
+            console.log("hello", n);
+        }(42));
+    }
+    expect_exact: ""
+}
+
+drop_fargs: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: false,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        !function(a_1) {
+            a++;
+        }(a++ + (a && console.log(a)));
+        console.log(a);
+    }
+    expect: {
+        var a = 1;
+        ++a && console.log(a),
+        a++;
+        console.log(a);
+    }
+    expect_stdout: [
+        "2",
+        "3",
+    ]
+}
+
+keep_fargs: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        !function(a_1) {
+            a++;
+        }(a++ + (a && console.log(a)));
+        console.log(a);
+    }
+    expect: {
+        var a = 1;
+        ++a && console.log(a),
+        a++;
+        console.log(a);
+    }
+    expect_stdout: [
+        "2",
+        "3",
+    ]
+}

test/compress/issue-2871.js

@@ -0,0 +1,37 @@
+comparison_with_undefined: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        a == undefined;
+        a != undefined;
+        a === undefined;
+        a !== undefined;
+
+        undefined == a;
+        undefined != a;
+        undefined === a;
+        undefined !== a;
+
+        void 0 == a;
+        void 0 != a;
+        void 0 === a;
+        void 0 !== a;
+    }
+    expect: {
+        null == a;
+        null != a;
+        void 0 === a;
+        void 0 !== a;
+
+        null == a;
+        null != a;
+        void 0 === a;
+        void 0 !== a;
+
+        null == a;
+        null != a;
+        void 0 === a;
+        void 0 !== a;
+    }
+}

test/compress/issue-2989.js

@@ -0,0 +1,21 @@
+inline_script_off: {
+    beautify = {
+        inline_script: false,
+    }
+    input: {
+        console.log("</sCrIpT>");
+    }
+    expect_exact: 'console.log("</sCrIpT>");'
+    expect_stdout: "</sCrIpT>"
+}
+
+inline_script_on: {
+    beautify = {
+        inline_script: true,
+    }
+    input: {
+        console.log("</sCrIpT>");
+    }
+    expect_exact: 'console.log("<\\/sCrIpT>");'
+    expect_stdout: "</sCrIpT>"
+}

test/compress/issue-368.js

@@ -1,6 +1,6 @@
 collapse: {
     options = {
-        cascade: true,
+        collapse_vars: true,
         sequences: true,
         side_effects: true,
         unused: true,
@@ -41,7 +41,7 @@ collapse: {
             return void 0 !== ('function' === typeof b ? b() : b) && c();
         }
         function f2(b) {
-            return b = c(), 'stirng' == typeof ('function' === typeof b ? b() : b) && d();
+            return 'stirng' == typeof ('function' === typeof (b = c()) ? b() : b) && d();
         }
         function f3(c) {
             var a;

test/compress/issue-3768.js

@@ -0,0 +1,128 @@
+mangle: {
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        var e = eval, x = 42;
+        (function() {
+            console.log(e("typeof x"));
+        })();
+    }
+    expect: {
+        var e = eval, x = 42;
+        (function() {
+            console.log(e("typeof x"));
+        })();
+    }
+    expect_stdout: true
+}
+
+compress: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            var a = 42;
+            return eval("typeof a");
+        }(), function(e) {
+            var a = null;
+            return e("typeof a");
+        }(eval), function(eval) {
+            var a = false;
+            return eval("typeof a");
+        }(eval), function(f) {
+            var a = "STRING";
+            var eval = f;
+            return eval("typeof a");
+        }(eval), function(g) {
+            var a = eval;
+            function eval() {
+                return g;
+            }
+            return eval()("typeof a");
+        }(eval));
+    }
+    expect: {
+        console.log(function() {
+            var a = 42;
+            return eval("typeof a");
+        }(), (0, eval)("typeof a"), function(eval) {
+            var a = false;
+            return eval("typeof a");
+        }(eval), function(f) {
+            var a = "STRING";
+            var eval = f;
+            return eval("typeof a");
+        }(eval), function(g) {
+            var a = eval;
+            function eval() {
+                return g;
+            }
+            return eval()("typeof a");
+        }(eval));
+    }
+    expect_stdout: "number undefined boolean string undefined"
+}
+
+call_arg_1: {
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        var z = "foo";
+        (function() {
+            var z = false;
+            (function(e) {
+                var z = 42;
+                e("console.log(typeof z)");
+            })(eval);
+        })();
+    }
+    expect: {
+        var z = "foo";
+        (function() {
+            var o = false;
+            (function(o) {
+                var a = 42;
+                o("console.log(typeof z)");
+            })(eval);
+        })();
+    }
+    expect_stdout: true
+}
+
+call_arg_2: {
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        function eval() {
+            console.log("PASS");
+        }
+        var z = "foo";
+        (function() {
+            var z = false;
+            (function(e) {
+                var z = 42;
+                e("console.log(typeof z)");
+            })(eval);
+        })();
+    }
+    expect: {
+        function n() {
+            console.log("PASS");
+        }
+        var o = "foo";
+        (function() {
+            var o = false;
+            (function(o) {
+                var n = 42;
+                o("console.log(typeof z)");
+            })(n);
+        })();
+    }
+    expect_stdout: "PASS"
+}

test/compress/issue-44.js

@@ -1,5 +1,7 @@
 issue_44_valid_ast_1: {
-    options = { unused: true };
+    options = {
+        unused: true,
+    }
     input: {
         function a(b) {
             for (var i = 0, e = b.qoo(); ; i++) {}
@@ -14,7 +16,9 @@ issue_44_valid_ast_1: {
 }
 
 issue_44_valid_ast_2: {
-    options = { unused: true };
+    options = {
+        unused: true,
+    }
     input: {
         function a(b) {
             if (foo) for (var i = 0, e = b.qoo(); ; i++) {}

test/compress/issue-59.js

@@ -1,8 +1,8 @@
 keep_continue: {
     options = {
         dead_code: true,
-        evaluate: true
-    };
+        evaluate: true,
+    }
     input: {
         while (a) {
             if (b) {

test/compress/issue-597.js

@@ -1,5 +1,5 @@
 NaN_and_Infinity_must_have_parens: {
-    options = {};
+    options = {}
     input: {
         Infinity.toString();
         NaN.toString();
@@ -11,7 +11,7 @@ NaN_and_Infinity_must_have_parens: {
 }
 
 NaN_and_Infinity_should_not_be_replaced_when_they_are_redefined: {
-    options = {};
+    options = {}
     input: {
         var Infinity, NaN;
         Infinity.toString();