v3.12.2

fixes #4380

.github/workflows/ci.yml

@@ -1,20 +1,28 @@
 name: CI
-on: [ push, pull_request ]
+on:
+  pull_request:
+  push:
+    branches: [ master ]
 jobs:
   test:
     strategy:
       matrix:
-        node: [ "0.10", "0.12", "4", "6", "8", "10", latest ]
+        node: [ "0.8", "0.10", "0.12", "4", "6", "8", "10", "12", 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@v1
-      - uses: actions/cache@v1
+      - uses: actions/checkout@v2
+      - uses: actions/cache@v2
         with:
           path: tmp
           key: tmp ${{ matrix.script }}
@@ -24,7 +32,7 @@ jobs:
           git clone --branch v1.5.4 --depth 1 https://github.com/jasongin/nvs.git ~/.nvs
           while ! timeout 60 bash -c '. ~/.nvs/nvs.sh add $NODE && nvs use $NODE'; do
             cd ~/.nvs
-            git clean -xdf
+            while !(git clean -xdf); do echo "'git clean' failed - retrying..."; done
             cd -
           done
           . ~/.nvs/nvs.sh --version
@@ -33,6 +41,7 @@ jobs:
           npm config set audit false
           npm config set optional false
           npm config set save false
+          npm config set strict-ssl false
           npm config set update-notifier false
           npm --version
           while !(npm install); do echo "'npm install' failed - retrying..."; done

.github/workflows/ufuzz.yml

@@ -1,7 +1,13 @@
 name: Fuzzing
 on:
+  pull_request:
   schedule:
-    - cron: "*/15 * * * *"
+    - 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:
@@ -11,23 +17,28 @@ jobs:
     name: ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v2
       - name: Perform fuzzing
         shell: bash
         run: |
           git clone --branch v1.5.4 --depth 1 https://github.com/jasongin/nvs.git ~/.nvs
-          while ! timeout 60 bash -c '. ~/.nvs/nvs.sh add 10 && nvs use 10'; do
+          while ! timeout 60 bash -c '. ~/.nvs/nvs.sh add 8 && nvs use 8'; do
             cd ~/.nvs
-            git clean -xdf
+            while !(git clean -xdf); do echo "'git clean' failed - retrying..."; done
             cd -
           done
           . ~/.nvs/nvs.sh --version
-          nvs use 10
+          nvs use 8
           node --version
           npm config set audit false
           npm config set optional false
           npm config set save false
+          npm config set strict-ssl false
           npm config set update-notifier false
           npm --version
           while !(npm install); do echo "'npm install' failed - retrying..."; done
-          node test/ufuzz/job 3600000
+          if [[ $CAUSE == "schedule" ]]; then
+            node test/ufuzz/job $BASE_URL $TOKEN $RUN_NUM
+          else
+            node test/ufuzz/job 5000
+          fi

README.md

@@ -4,10 +4,12 @@ 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 JavaScript (ECMAScript 5).
-- To minify ECMAScript 2015 or above, transpile using tools like [Babel](https://babeljs.io/).
+- **`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)**.
+- **Documentation for UglifyJS `2.x` releases can be found [here](https://github.com/mishoo/UglifyJS/tree/v2.x)**.
+- `uglify-js` supports ECMAScript 5 and some newer language features.
+- To minify ECMAScript 2015 or above, you may need to transpile using tools like
+  [Babel](https://babeljs.io/).
 
 Install
 -------
@@ -126,6 +128,7 @@ a double dash to prevent input files being used as option arguments:
                                 `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
@@ -134,6 +137,10 @@ a double dash to prevent input files being used as option arguments:
     --toplevel                  Compress and/or mangle variables in top level scope.
     --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
@@ -159,6 +166,9 @@ Additional options:
 
 - `--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.
@@ -208,13 +218,12 @@ Example:
 To enable the mangler you need to pass `--mangle` (`-m`).  The following
 (comma-separated) options are supported:
 
-- `toplevel` (default `false`) -- mangle names declared in the top level scope.
+- `eval` (default `false`) -- mangle names visible in scopes where `eval` or
+  `with` are used.
 
-- `eval` (default `false`) -- mangle names visible in scopes where `eval` or `with` are used.
-
-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:
+- `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:
 
       uglifyjs ... -m reserved=['$','require','exports']
 
@@ -516,6 +525,9 @@ if (result.error) throw result.error;
 - `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
@@ -593,6 +605,9 @@ 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
@@ -650,8 +665,8 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 - `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 `mangle` enabled, the `compress` option `passes` set to `2` or higher,
-  and the `compress` option `toplevel` enabled.
+  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)
@@ -682,6 +697,8 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 - `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.
@@ -736,6 +753,8 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   annotation `/*@__PURE__*/` or `/*#__PURE__*/` immediately precedes the call. For
   example: `/*@__PURE__*/foo();`
 
+- `spread` (default: `true`) -- flatten spread expressions.
+
 - `strings` (default: `true`) -- compact string concatenations.
 
 - `switches` (default: `true`) -- de-duplicate and remove unreachable `switch` branches
@@ -776,6 +795,9 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 - `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
+
 ## Mangle options
 
 - `eval` (default `false`) -- Pass `true` to mangle names visible in scopes
@@ -857,6 +879,8 @@ can pass additional arguments that control the code output:
   }
   ```
 
+- `galio` (default `false`) -- enable workarounds for ANT Galio bugs
+
 - `indent_level` (default `4`)
 
 - `indent_start` (default `0`) -- prefix all lines by that many spaces
@@ -895,8 +919,7 @@ can pass additional arguments that control the code output:
 
 - `shebang` (default `true`) -- preserve shebang `#!` in preamble (bash scripts)
 
-- `webkit` (default `false`) -- enable workarounds for WebKit bugs.
-  PhantomJS users should set this option to `true`.
+- `v8` (default `false`) -- enable workarounds for Chrome & Node.js bugs
 
 - `width` (default `80`) -- only takes effect when beautification is on, this
   specifies an (orientative) line width that the beautifier will try to
@@ -906,7 +929,7 @@ can pass additional arguments that control the code output:
 
 - `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
 
@@ -1065,8 +1088,8 @@ var result = UglifyJS.minify(ast, {
 ### Working with Uglify AST
 
 Transversal and transformation of the native AST can be performed through
-[`TreeWalker`](https://github.com/mishoo/UglifyJS2/blob/master/lib/ast.js) and
-[`TreeTransformer`](https://github.com/mishoo/UglifyJS2/blob/master/lib/transform.js)
+[`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
@@ -1127,7 +1150,7 @@ To enable fast minify mode with the API use:
 UglifyJS.minify(code, { compress: false, mangle: true });
 ```
 
-#### Source maps and debugging
+### 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
@@ -1139,6 +1162,10 @@ disable the Uglify `compress` option and just use `mangle`.
 
 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.
@@ -1150,3 +1177,35 @@ To allow for better optimizations, the compiler makes various assumptions:
 - 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:
+  ```js
+  ({
+    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:
+  ```js
+  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.

appveyor.yml

@@ -1,5 +0,0 @@
-build: off
-matrix:
-  fast_finish: true
-test_script:
-  - echo No longer in use

bin/uglifyjs

@@ -8,166 +8,254 @@ require("../tools/exit");
 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", "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:");
-        text.push(format_object(options[option]));
-        text.push("");
+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);
+    });
 }
-    return text.join("\n");
-};
-program.option("-p, --parse <options>", "Specify parser options.", parse_js());
-program.option("-c, --compress [options]", "Enable compressor/specify compressor options.", parse_js());
-program.option("-m, --mangle [options]", "Mangle names/specify mangler options.", parse_js());
-program.option("--mangle-props [options]", "Mangle properties/specify mangler options.", parse_js());
-program.option("-b, --beautify [options]", "Beautify output/specify output options.", parse_js());
-program.option("-O, --output-opts [options]", "Output options (beautify disabled).", parse_js());
-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("-e, --enclose [arg[,...][:value[,...]]]", "Embed everything in a big function, with configurable argument(s) & value(s).");
-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("--rename", "Force symbol expansion.");
-program.option("--no-rename", "Disable symbol expansion.");
-program.option("--self", "Build UglifyJS as a library (implies --wrap UglifyJS)");
-program.option("--source-map [options]", "Enable source map/specify source map options.", parse_js());
-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.option("--reduce-test", "Reduce a standalone `console.log` based test case.");
-program.arguments("[files...]").parseArgv(process.argv);
-if (program.configFile) {
-    options = JSON.parse(read_file(program.configFile));
-    if (options.mangle && options.mangle.properties && options.mangle.properties.regex) {
-        options.mangle.properties.regex = UglifyJS.parse(options.mangle.properties.regex, {
-            expression: true
+
+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).",
+                "  --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.",
+                "  --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;
         }
-}
-if (!program.output && program.sourceMap && program.sourceMap.url != "inline") {
-    fatal("cannot write source map to STDOUT");
-}
-[
-    "compress",
-    "enclose",
-    "ie8",
-    "mangle",
-    "sourceMap",
-    "toplevel",
-    "wrap"
-].forEach(function(name) {
-    if (name in program) {
-        options[name] = program[name];
-    }
-});
-if (program.verbose) {
+        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 "ie8":
+      case "timings":
+      case "toplevel":
+      case "validate":
+      case "webkit":
+        options[name] = true;
+        break;
+      case "keep-fnames":
+        options.keep_fnames = true;
+        break;
+      case "wrap":
+        options[name] = read_value(true);
+        break;
+      case "verbose":
         options.warnings = "verbose";
-} else if (program.warn) {
-    options.warnings = true;
+        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 "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 (!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 (output == "ast") options.output = {
+    ast: true,
+    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;
 }
-if (program.beautify) {
-    options.output = typeof program.beautify == "object" ? program.beautify : {};
-    if (!("beautify" in options.output)) {
-        options.output.beautify = true;
-    }
-}
-if (program.outputOpts) {
-    if (program.beautify) fatal("--beautify cannot be used with --output-opts");
-    options.output = typeof program.outputOpts == "object" ? program.outputOpts : {};
-}
-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;
-}
-if (program.nameCache) {
-    options.nameCache = JSON.parse(read_file(program.nameCache, "{}"));
-}
-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("inline source map only works with built-in parser");
-    }
-}
-if (~program.rawArgs.indexOf("--rename")) {
-    options.rename = true;
-} else if (!program.rename) {
-    options.rename = false;
-}
 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.self) {
-    if (program.args.length) UglifyJS.AST_Node.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) {
-        files[convert_path(name)] = read_file(name);
-    });
-    run();
-} else if (program.args.length) {
-    simple_glob(program.args).forEach(function(name) {
+    paths = UglifyJS.FILES;
+}
+if (paths.length) {
+    simple_glob(paths).forEach(function(name) {
         files[convert_path(name)] = read_file(name);
     });
     run();
@@ -188,15 +276,16 @@ function convert_ast(fn) {
 }
 
 function run() {
-    var content = program.sourceMap && program.sourceMap.content;
+    var content = options.sourceMap && options.sourceMap.content;
     if (content && content != "inline") {
-        UglifyJS.AST_Node.info("Using input source map: " + content);
+        UglifyJS.AST_Node.info("Using input source map: {content}", {
+            content : content,
+        });
         options.sourceMap.content = read_file(content, content);
     }
-    if (program.timings) options.timings = true;
     try {
-        if (program.parse) {
-            if (program.parse.acorn) {
+        if (options.parse) {
+            if (options.parse.acorn) {
                 files = convert_ast(function(toplevel, name) {
                     return require("acorn").parse(files[name], {
                         locations: true,
@@ -204,7 +293,7 @@ function run() {
                         sourceFile: name
                     });
                 });
-            } else if (program.parse.spidermonkey) {
+            } else if (options.parse.spidermonkey) {
                 files = convert_ast(function(toplevel, name) {
                     var obj = JSON.parse(files[name]);
                     if (!toplevel) return obj;
@@ -216,14 +305,17 @@ function run() {
     } catch (ex) {
         fatal(ex);
     }
-    if (program.reduceTest) {
-        // load on demand - assumes dev tree checked out
+    var result;
+    if (specified["reduce-test"]) {
+        // load on demand - assumes cloned repository
         var reduce_test = require("../test/reduce");
-        var testcase = files[0] || files[Object.keys(files)[0]];
-        var result = reduce_test(testcase, options, {verbose: true});
-    }
-    else {
-        var result = UglifyJS.minify(files, options);
+        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;
@@ -253,9 +345,18 @@ function run() {
             print_error(format_object(ex.defs));
         }
         fatal(ex);
-    } else if (program.output == "ast") {
+    } else if (output == "ast") {
         if (!options.compress && !options.mangle) {
-            result.ast.figure_out_scope({});
+            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) {
@@ -282,26 +383,22 @@ function run() {
             }
             return value;
         }, 2));
-    } else if (program.output == "spidermonkey") {
+    } else if (output == "spidermonkey") {
         print(JSON.stringify(UglifyJS.minify(result.code, {
             compress: false,
             mangle: false,
             output: {
                 ast: true,
                 code: false
-            }
+            },
         }).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);
-        }
+    } else if (output) {
+        fs.writeFileSync(output, result.code);
+        if (result.map) fs.writeFileSync(output + ".map", result.map);
     } else {
         print(result.code);
     }
-    if (program.nameCache) {
-        fs.writeFileSync(program.nameCache, JSON.stringify(options.nameCache));
-    }
+    if (nameCache) fs.writeFileSync(nameCache, JSON.stringify(options.nameCache));
     if (result.timings) for (var phase in result.timings) {
         print_error("- " + phase + ": " + result.timings[phase].toFixed(3) + "s");
     }
@@ -337,7 +434,7 @@ 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);
@@ -357,10 +454,9 @@ function read_file(path, default_value) {
     }
 }
 
-function parse_js(flag) {
-    return function(value, options) {
-        options = options || {};
-        try {
+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) {
@@ -398,7 +494,6 @@ function parse_js(flag) {
     }
     return options;
 }
-}
 
 function skip_key(key) {
     return skip_keys.indexOf(key) >= 0;

lib/minify.js

@@ -33,7 +33,9 @@ function read_source_map(name, toplevel) {
             return to_ascii(match[2]);
         }
     }
-    AST_Node.warn("inline source map not found: " + name);
+    AST_Node.warn("inline source map not found: {name}", {
+        name: name,
+    });
 }
 
 function parse_source_map(content) {
@@ -85,9 +87,12 @@ function minify(files, options) {
             sourceMap: false,
             timings: false,
             toplevel: false,
+            validate: false,
             warnings: false,
+            webkit: false,
             wrap: false,
         }, true);
+        if (options.validate) AST_Node.enable_validation();
         var timings = options.timings && {
             start: Date.now()
         };
@@ -97,6 +102,7 @@ function minify(files, options) {
         set_shorthand("ie8", options, [ "compress", "mangle", "output" ]);
         set_shorthand("keep_fnames", options, [ "compress", "mangle" ]);
         set_shorthand("toplevel", options, [ "compress", "mangle" ]);
+        set_shorthand("webkit", options, [ "mangle", "output" ]);
         var quoted_props;
         if (options.mangle) {
             options.mangle = defaults(options.mangle, {
@@ -107,6 +113,7 @@ function minify(files, options) {
                 properties: false,
                 reserved: [],
                 toplevel: false,
+                webkit: false,
             }, true);
             if (options.mangle.properties) {
                 if (typeof options.mangle.properties != "object") {
@@ -129,6 +136,7 @@ function minify(files, options) {
                 content: null,
                 filename: null,
                 includeSources: false,
+                names: true,
                 root: null,
                 url: null,
             }, true);
@@ -138,7 +146,7 @@ function minify(files, options) {
             warnings.push(warning);
         }, options.warnings == "verbose");
         if (timings) timings.parse = Date.now();
-        var source_maps, toplevel;
+        var toplevel;
         if (files instanceof AST_Toplevel) {
             toplevel = files;
         } else {
@@ -151,19 +159,17 @@ function minify(files, options) {
             if (typeof source_map_content == "string" && source_map_content != "inline") {
                 source_map_content = parse_source_map(source_map_content);
             }
-            source_maps = source_map_content && Object.create(null);
+            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 = toplevel = parse(files[name], options.parse);
-                if (source_maps) {
                 if (source_map_content == "inline") {
                     var inlined_content = read_source_map(name, toplevel);
                     if (inlined_content) {
-                            source_maps[name] = parse_source_map(inlined_content);
-                        }
-                    } else {
-                        source_maps[name] = source_map_content;
+                        options.sourceMap.orig[name] = parse_source_map(inlined_content);
                     }
+                } else if (source_map_content) {
+                    options.sourceMap.orig[name] = source_map_content;
                 }
             }
         }
@@ -177,13 +183,17 @@ function minify(files, options) {
             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.compress = Date.now();
-        if (options.compress) toplevel = new Compressor(options.compress).compress(toplevel);
+        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();
@@ -192,9 +202,7 @@ function minify(files, options) {
             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) {
@@ -202,12 +210,7 @@ function minify(files, options) {
         }
         if (!HOP(options.output, "code") || options.output.code) {
             if (options.sourceMap) {
-                options.output.source_map = SourceMap({
-                    content: options.sourceMap.includeSources,
-                    file: options.sourceMap.filename,
-                    orig: source_maps,
-                    root: options.sourceMap.root
-                });
+                options.output.source_map = SourceMap(options.sourceMap);
                 if (options.sourceMap.includeSources) {
                     if (files instanceof AST_Toplevel) {
                         throw new Error("original source content unavailable");
@@ -259,5 +262,8 @@ function minify(files, options) {
         return result;
     } catch (ex) {
         return { error: ex };
+    } finally {
+        AST_Node.log_function();
+        AST_Node.disable_validation();
     }
 }

lib/mozilla-ast.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -111,13 +111,10 @@
             var args = {
                 start    : my_start_token(key),
                 end      : my_end_token(M.value),
-                key      : key.type == "Identifier" ? key.name : key.value,
+                key      : "" + key[key.type == "Identifier" ? "name" : "value"],
                 value    : from_moz(M.value)
             };
             if (M.kind == "init") return new AST_ObjectKeyVal(args);
-            args.key = new AST_SymbolAccessor({
-                name: args.key
-            });
             args.value = new AST_Accessor(args.value);
             if (M.kind == "get") return new AST_ObjectGetter(args);
             if (M.kind == "set") return new AST_ObjectSetter(args);
@@ -212,7 +209,14 @@
                             end   : my_end_token(M),
                             name  : M.name
                         });
-        }
+        },
+        ThisExpression: function(M) {
+            return new AST_This({
+                start : my_start_token(M),
+                end   : my_end_token(M),
+                name  : "this",
+            });
+        },
     };
 
     MOZ_TO_ME.UpdateExpression =
@@ -245,7 +249,6 @@
     map("VariableDeclarator", AST_VarDef, "id>name, init>value");
     map("CatchClause", AST_Catch, "param>argname, body%body");
 
-    map("ThisExpression", AST_This);
     map("BinaryExpression", AST_Binary, "operator=operator, left>left, right>right");
     map("LogicalExpression", AST_Binary, "operator=operator, left>left, right>right");
     map("AssignmentExpression", AST_Assign, "operator=operator, left>left, right>right");
@@ -379,7 +382,7 @@
     def_to_moz(AST_ObjectProperty, function To_Moz_Property(M) {
         var key = {
             type: "Literal",
-            value: M.key instanceof AST_SymbolAccessor ? M.key.name : M.key
+            value: M.key
         };
         var kind;
         if (M instanceof AST_ObjectKeyVal) {
@@ -407,6 +410,10 @@
         };
     });
 
+    def_to_moz(AST_This, function To_Moz_ThisExpression() {
+        return { type: "ThisExpression" };
+    });
+
     def_to_moz(AST_RegExp, function To_Moz_RegExpLiteral(M) {
         var flags = M.value.toString().match(/[gimuy]*$/)[0];
         var value = "/" + M.value.raw_source + "/" + flags;

lib/parse.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -44,21 +44,23 @@
 
 "use strict";
 
-var KEYWORDS = 'break case catch const continue debugger default delete do else finally for function if in instanceof new return switch throw try typeof var void while with';
-var KEYWORDS_ATOM = 'false null true';
-var RESERVED_WORDS = 'abstract boolean byte char class double enum export extends final float goto implements import int interface let long native package private protected public short static super synchronized this throws transient volatile yield'
-    + " " + KEYWORDS_ATOM + " " + KEYWORDS;
-var KEYWORDS_BEFORE_EXPRESSION = 'return new delete throw else case';
+var KEYWORDS = "break case catch const continue debugger default delete do else finally for function if in instanceof let new return switch throw try typeof var void while with";
+var KEYWORDS_ATOM = "false null true";
+var RESERVED_WORDS = [
+    "await abstract boolean byte char class double enum export extends final float goto implements import int interface long native package private protected public short static super synchronized this throws transient volatile yield",
+    KEYWORDS_ATOM,
+    KEYWORDS,
+].join(" ");
+var KEYWORDS_BEFORE_EXPRESSION = "return new delete throw else case";
 
 KEYWORDS = makePredicate(KEYWORDS);
 RESERVED_WORDS = makePredicate(RESERVED_WORDS);
 KEYWORDS_BEFORE_EXPRESSION = makePredicate(KEYWORDS_BEFORE_EXPRESSION);
 KEYWORDS_ATOM = makePredicate(KEYWORDS_ATOM);
 
-var OPERATOR_CHARS = makePredicate(characters("+-*&%=<>!?|~^"));
-
-var RE_HEX_NUMBER = /^0x[0-9a-f]+$/i;
-var RE_OCT_NUMBER = /^0[0-7]+$/;
+var RE_BIN_NUMBER = /^0b([01]+)$/i;
+var RE_HEX_NUMBER = /^0x([0-9a-f]+)$/i;
+var RE_OCT_NUMBER = /^0o?([0-7]+)$/i;
 
 var OPERATORS = makePredicate([
     "in",
@@ -107,31 +109,21 @@ var OPERATORS = makePredicate([
     "||"
 ]);
 
-var WHITESPACE_CHARS = makePredicate(characters(" \u00a0\n\r\t\f\u000b\u200b\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u2028\u2029\u202f\u205f\u3000\uFEFF"));
+var NEWLINE_CHARS = "\n\r\u2028\u2029";
+var OPERATOR_CHARS = "+-*&%=<>!?|~^";
+var PUNC_BEFORE_EXPRESSION = "[{(,;:";
+var PUNC_CHARS = PUNC_BEFORE_EXPRESSION + ")}]";
+var WHITESPACE_CHARS = NEWLINE_CHARS + " \u00a0\t\f\u000b\u200b\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u202f\u205f\u3000\uFEFF";
+var NON_IDENTIFIER_CHARS = makePredicate(characters("./'\"" + OPERATOR_CHARS + PUNC_CHARS + WHITESPACE_CHARS));
 
-var NEWLINE_CHARS = makePredicate(characters("\n\r\u2028\u2029"));
-
-var PUNC_BEFORE_EXPRESSION = makePredicate(characters("[{(,;:"));
-
-var PUNC_CHARS = makePredicate(characters("[]{}(),;:"));
+NEWLINE_CHARS = makePredicate(characters(NEWLINE_CHARS));
+OPERATOR_CHARS = makePredicate(characters(OPERATOR_CHARS));
+PUNC_BEFORE_EXPRESSION = makePredicate(characters(PUNC_BEFORE_EXPRESSION));
+PUNC_CHARS = makePredicate(characters(PUNC_CHARS));
+WHITESPACE_CHARS = makePredicate(characters(WHITESPACE_CHARS));
 
 /* -----[ Tokenizer ]----- */
 
-// regexps adapted from http://xregexp.com/plugins/#unicode
-var UNICODE = {
-    letter: new RegExp("[\\u0041-\\u005A\\u0061-\\u007A\\u00AA\\u00B5\\u00BA\\u00C0-\\u00D6\\u00D8-\\u00F6\\u00F8-\\u02C1\\u02C6-\\u02D1\\u02E0-\\u02E4\\u02EC\\u02EE\\u0370-\\u0374\\u0376\\u0377\\u037A-\\u037D\\u037F\\u0386\\u0388-\\u038A\\u038C\\u038E-\\u03A1\\u03A3-\\u03F5\\u03F7-\\u0481\\u048A-\\u052F\\u0531-\\u0556\\u0559\\u0561-\\u0587\\u05D0-\\u05EA\\u05F0-\\u05F2\\u0620-\\u064A\\u066E\\u066F\\u0671-\\u06D3\\u06D5\\u06E5\\u06E6\\u06EE\\u06EF\\u06FA-\\u06FC\\u06FF\\u0710\\u0712-\\u072F\\u074D-\\u07A5\\u07B1\\u07CA-\\u07EA\\u07F4\\u07F5\\u07FA\\u0800-\\u0815\\u081A\\u0824\\u0828\\u0840-\\u0858\\u08A0-\\u08B2\\u0904-\\u0939\\u093D\\u0950\\u0958-\\u0961\\u0971-\\u0980\\u0985-\\u098C\\u098F\\u0990\\u0993-\\u09A8\\u09AA-\\u09B0\\u09B2\\u09B6-\\u09B9\\u09BD\\u09CE\\u09DC\\u09DD\\u09DF-\\u09E1\\u09F0\\u09F1\\u0A05-\\u0A0A\\u0A0F\\u0A10\\u0A13-\\u0A28\\u0A2A-\\u0A30\\u0A32\\u0A33\\u0A35\\u0A36\\u0A38\\u0A39\\u0A59-\\u0A5C\\u0A5E\\u0A72-\\u0A74\\u0A85-\\u0A8D\\u0A8F-\\u0A91\\u0A93-\\u0AA8\\u0AAA-\\u0AB0\\u0AB2\\u0AB3\\u0AB5-\\u0AB9\\u0ABD\\u0AD0\\u0AE0\\u0AE1\\u0B05-\\u0B0C\\u0B0F\\u0B10\\u0B13-\\u0B28\\u0B2A-\\u0B30\\u0B32\\u0B33\\u0B35-\\u0B39\\u0B3D\\u0B5C\\u0B5D\\u0B5F-\\u0B61\\u0B71\\u0B83\\u0B85-\\u0B8A\\u0B8E-\\u0B90\\u0B92-\\u0B95\\u0B99\\u0B9A\\u0B9C\\u0B9E\\u0B9F\\u0BA3\\u0BA4\\u0BA8-\\u0BAA\\u0BAE-\\u0BB9\\u0BD0\\u0C05-\\u0C0C\\u0C0E-\\u0C10\\u0C12-\\u0C28\\u0C2A-\\u0C39\\u0C3D\\u0C58\\u0C59\\u0C60\\u0C61\\u0C85-\\u0C8C\\u0C8E-\\u0C90\\u0C92-\\u0CA8\\u0CAA-\\u0CB3\\u0CB5-\\u0CB9\\u0CBD\\u0CDE\\u0CE0\\u0CE1\\u0CF1\\u0CF2\\u0D05-\\u0D0C\\u0D0E-\\u0D10\\u0D12-\\u0D3A\\u0D3D\\u0D4E\\u0D60\\u0D61\\u0D7A-\\u0D7F\\u0D85-\\u0D96\\u0D9A-\\u0DB1\\u0DB3-\\u0DBB\\u0DBD\\u0DC0-\\u0DC6\\u0E01-\\u0E30\\u0E32\\u0E33\\u0E40-\\u0E46\\u0E81\\u0E82\\u0E84\\u0E87\\u0E88\\u0E8A\\u0E8D\\u0E94-\\u0E97\\u0E99-\\u0E9F\\u0EA1-\\u0EA3\\u0EA5\\u0EA7\\u0EAA\\u0EAB\\u0EAD-\\u0EB0\\u0EB2\\u0EB3\\u0EBD\\u0EC0-\\u0EC4\\u0EC6\\u0EDC-\\u0EDF\\u0F00\\u0F40-\\u0F47\\u0F49-\\u0F6C\\u0F88-\\u0F8C\\u1000-\\u102A\\u103F\\u1050-\\u1055\\u105A-\\u105D\\u1061\\u1065\\u1066\\u106E-\\u1070\\u1075-\\u1081\\u108E\\u10A0-\\u10C5\\u10C7\\u10CD\\u10D0-\\u10FA\\u10FC-\\u1248\\u124A-\\u124D\\u1250-\\u1256\\u1258\\u125A-\\u125D\\u1260-\\u1288\\u128A-\\u128D\\u1290-\\u12B0\\u12B2-\\u12B5\\u12B8-\\u12BE\\u12C0\\u12C2-\\u12C5\\u12C8-\\u12D6\\u12D8-\\u1310\\u1312-\\u1315\\u1318-\\u135A\\u1380-\\u138F\\u13A0-\\u13F4\\u1401-\\u166C\\u166F-\\u167F\\u1681-\\u169A\\u16A0-\\u16EA\\u16EE-\\u16F8\\u1700-\\u170C\\u170E-\\u1711\\u1720-\\u1731\\u1740-\\u1751\\u1760-\\u176C\\u176E-\\u1770\\u1780-\\u17B3\\u17D7\\u17DC\\u1820-\\u1877\\u1880-\\u18A8\\u18AA\\u18B0-\\u18F5\\u1900-\\u191E\\u1950-\\u196D\\u1970-\\u1974\\u1980-\\u19AB\\u19C1-\\u19C7\\u1A00-\\u1A16\\u1A20-\\u1A54\\u1AA7\\u1B05-\\u1B33\\u1B45-\\u1B4B\\u1B83-\\u1BA0\\u1BAE\\u1BAF\\u1BBA-\\u1BE5\\u1C00-\\u1C23\\u1C4D-\\u1C4F\\u1C5A-\\u1C7D\\u1CE9-\\u1CEC\\u1CEE-\\u1CF1\\u1CF5\\u1CF6\\u1D00-\\u1DBF\\u1E00-\\u1F15\\u1F18-\\u1F1D\\u1F20-\\u1F45\\u1F48-\\u1F4D\\u1F50-\\u1F57\\u1F59\\u1F5B\\u1F5D\\u1F5F-\\u1F7D\\u1F80-\\u1FB4\\u1FB6-\\u1FBC\\u1FBE\\u1FC2-\\u1FC4\\u1FC6-\\u1FCC\\u1FD0-\\u1FD3\\u1FD6-\\u1FDB\\u1FE0-\\u1FEC\\u1FF2-\\u1FF4\\u1FF6-\\u1FFC\\u2071\\u207F\\u2090-\\u209C\\u2102\\u2107\\u210A-\\u2113\\u2115\\u2119-\\u211D\\u2124\\u2126\\u2128\\u212A-\\u212D\\u212F-\\u2139\\u213C-\\u213F\\u2145-\\u2149\\u214E\\u2160-\\u2188\\u2C00-\\u2C2E\\u2C30-\\u2C5E\\u2C60-\\u2CE4\\u2CEB-\\u2CEE\\u2CF2\\u2CF3\\u2D00-\\u2D25\\u2D27\\u2D2D\\u2D30-\\u2D67\\u2D6F\\u2D80-\\u2D96\\u2DA0-\\u2DA6\\u2DA8-\\u2DAE\\u2DB0-\\u2DB6\\u2DB8-\\u2DBE\\u2DC0-\\u2DC6\\u2DC8-\\u2DCE\\u2DD0-\\u2DD6\\u2DD8-\\u2DDE\\u2E2F\\u3005-\\u3007\\u3021-\\u3029\\u3031-\\u3035\\u3038-\\u303C\\u3041-\\u3096\\u309D-\\u309F\\u30A1-\\u30FA\\u30FC-\\u30FF\\u3105-\\u312D\\u3131-\\u318E\\u31A0-\\u31BA\\u31F0-\\u31FF\\u3400-\\u4DB5\\u4E00-\\u9FCC\\uA000-\\uA48C\\uA4D0-\\uA4FD\\uA500-\\uA60C\\uA610-\\uA61F\\uA62A\\uA62B\\uA640-\\uA66E\\uA67F-\\uA69D\\uA6A0-\\uA6EF\\uA717-\\uA71F\\uA722-\\uA788\\uA78B-\\uA78E\\uA790-\\uA7AD\\uA7B0\\uA7B1\\uA7F7-\\uA801\\uA803-\\uA805\\uA807-\\uA80A\\uA80C-\\uA822\\uA840-\\uA873\\uA882-\\uA8B3\\uA8F2-\\uA8F7\\uA8FB\\uA90A-\\uA925\\uA930-\\uA946\\uA960-\\uA97C\\uA984-\\uA9B2\\uA9CF\\uA9E0-\\uA9E4\\uA9E6-\\uA9EF\\uA9FA-\\uA9FE\\uAA00-\\uAA28\\uAA40-\\uAA42\\uAA44-\\uAA4B\\uAA60-\\uAA76\\uAA7A\\uAA7E-\\uAAAF\\uAAB1\\uAAB5\\uAAB6\\uAAB9-\\uAABD\\uAAC0\\uAAC2\\uAADB-\\uAADD\\uAAE0-\\uAAEA\\uAAF2-\\uAAF4\\uAB01-\\uAB06\\uAB09-\\uAB0E\\uAB11-\\uAB16\\uAB20-\\uAB26\\uAB28-\\uAB2E\\uAB30-\\uAB5A\\uAB5C-\\uAB5F\\uAB64\\uAB65\\uABC0-\\uABE2\\uAC00-\\uD7A3\\uD7B0-\\uD7C6\\uD7CB-\\uD7FB\\uF900-\\uFA6D\\uFA70-\\uFAD9\\uFB00-\\uFB06\\uFB13-\\uFB17\\uFB1D\\uFB1F-\\uFB28\\uFB2A-\\uFB36\\uFB38-\\uFB3C\\uFB3E\\uFB40\\uFB41\\uFB43\\uFB44\\uFB46-\\uFBB1\\uFBD3-\\uFD3D\\uFD50-\\uFD8F\\uFD92-\\uFDC7\\uFDF0-\\uFDFB\\uFE70-\\uFE74\\uFE76-\\uFEFC\\uFF21-\\uFF3A\\uFF41-\\uFF5A\\uFF66-\\uFFBE\\uFFC2-\\uFFC7\\uFFCA-\\uFFCF\\uFFD2-\\uFFD7\\uFFDA-\\uFFDC]"),
-    digit: new RegExp("[\\u0030-\\u0039\\u0660-\\u0669\\u06F0-\\u06F9\\u07C0-\\u07C9\\u0966-\\u096F\\u09E6-\\u09EF\\u0A66-\\u0A6F\\u0AE6-\\u0AEF\\u0B66-\\u0B6F\\u0BE6-\\u0BEF\\u0C66-\\u0C6F\\u0CE6-\\u0CEF\\u0D66-\\u0D6F\\u0DE6-\\u0DEF\\u0E50-\\u0E59\\u0ED0-\\u0ED9\\u0F20-\\u0F29\\u1040-\\u1049\\u1090-\\u1099\\u17E0-\\u17E9\\u1810-\\u1819\\u1946-\\u194F\\u19D0-\\u19D9\\u1A80-\\u1A89\\u1A90-\\u1A99\\u1B50-\\u1B59\\u1BB0-\\u1BB9\\u1C40-\\u1C49\\u1C50-\\u1C59\\uA620-\\uA629\\uA8D0-\\uA8D9\\uA900-\\uA909\\uA9D0-\\uA9D9\\uA9F0-\\uA9F9\\uAA50-\\uAA59\\uABF0-\\uABF9\\uFF10-\\uFF19]"),
-    non_spacing_mark: new RegExp("[\\u0300-\\u036F\\u0483-\\u0487\\u0591-\\u05BD\\u05BF\\u05C1\\u05C2\\u05C4\\u05C5\\u05C7\\u0610-\\u061A\\u064B-\\u065E\\u0670\\u06D6-\\u06DC\\u06DF-\\u06E4\\u06E7\\u06E8\\u06EA-\\u06ED\\u0711\\u0730-\\u074A\\u07A6-\\u07B0\\u07EB-\\u07F3\\u0816-\\u0819\\u081B-\\u0823\\u0825-\\u0827\\u0829-\\u082D\\u0900-\\u0902\\u093C\\u0941-\\u0948\\u094D\\u0951-\\u0955\\u0962\\u0963\\u0981\\u09BC\\u09C1-\\u09C4\\u09CD\\u09E2\\u09E3\\u0A01\\u0A02\\u0A3C\\u0A41\\u0A42\\u0A47\\u0A48\\u0A4B-\\u0A4D\\u0A51\\u0A70\\u0A71\\u0A75\\u0A81\\u0A82\\u0ABC\\u0AC1-\\u0AC5\\u0AC7\\u0AC8\\u0ACD\\u0AE2\\u0AE3\\u0B01\\u0B3C\\u0B3F\\u0B41-\\u0B44\\u0B4D\\u0B56\\u0B62\\u0B63\\u0B82\\u0BC0\\u0BCD\\u0C3E-\\u0C40\\u0C46-\\u0C48\\u0C4A-\\u0C4D\\u0C55\\u0C56\\u0C62\\u0C63\\u0CBC\\u0CBF\\u0CC6\\u0CCC\\u0CCD\\u0CE2\\u0CE3\\u0D41-\\u0D44\\u0D4D\\u0D62\\u0D63\\u0DCA\\u0DD2-\\u0DD4\\u0DD6\\u0E31\\u0E34-\\u0E3A\\u0E47-\\u0E4E\\u0EB1\\u0EB4-\\u0EB9\\u0EBB\\u0EBC\\u0EC8-\\u0ECD\\u0F18\\u0F19\\u0F35\\u0F37\\u0F39\\u0F71-\\u0F7E\\u0F80-\\u0F84\\u0F86\\u0F87\\u0F90-\\u0F97\\u0F99-\\u0FBC\\u0FC6\\u102D-\\u1030\\u1032-\\u1037\\u1039\\u103A\\u103D\\u103E\\u1058\\u1059\\u105E-\\u1060\\u1071-\\u1074\\u1082\\u1085\\u1086\\u108D\\u109D\\u135F\\u1712-\\u1714\\u1732-\\u1734\\u1752\\u1753\\u1772\\u1773\\u17B7-\\u17BD\\u17C6\\u17C9-\\u17D3\\u17DD\\u180B-\\u180D\\u18A9\\u1920-\\u1922\\u1927\\u1928\\u1932\\u1939-\\u193B\\u1A17\\u1A18\\u1A56\\u1A58-\\u1A5E\\u1A60\\u1A62\\u1A65-\\u1A6C\\u1A73-\\u1A7C\\u1A7F\\u1B00-\\u1B03\\u1B34\\u1B36-\\u1B3A\\u1B3C\\u1B42\\u1B6B-\\u1B73\\u1B80\\u1B81\\u1BA2-\\u1BA5\\u1BA8\\u1BA9\\u1C2C-\\u1C33\\u1C36\\u1C37\\u1CD0-\\u1CD2\\u1CD4-\\u1CE0\\u1CE2-\\u1CE8\\u1CED\\u1DC0-\\u1DE6\\u1DFD-\\u1DFF\\u20D0-\\u20DC\\u20E1\\u20E5-\\u20F0\\u2CEF-\\u2CF1\\u2DE0-\\u2DFF\\u302A-\\u302F\\u3099\\u309A\\uA66F\\uA67C\\uA67D\\uA6F0\\uA6F1\\uA802\\uA806\\uA80B\\uA825\\uA826\\uA8C4\\uA8E0-\\uA8F1\\uA926-\\uA92D\\uA947-\\uA951\\uA980-\\uA982\\uA9B3\\uA9B6-\\uA9B9\\uA9BC\\uAA29-\\uAA2E\\uAA31\\uAA32\\uAA35\\uAA36\\uAA43\\uAA4C\\uAAB0\\uAAB2-\\uAAB4\\uAAB7\\uAAB8\\uAABE\\uAABF\\uAAC1\\uABE5\\uABE8\\uABED\\uFB1E\\uFE00-\\uFE0F\\uFE20-\\uFE26]"),
-    space_combining_mark: new RegExp("[\\u0903\\u093E-\\u0940\\u0949-\\u094C\\u094E\\u0982\\u0983\\u09BE-\\u09C0\\u09C7\\u09C8\\u09CB\\u09CC\\u09D7\\u0A03\\u0A3E-\\u0A40\\u0A83\\u0ABE-\\u0AC0\\u0AC9\\u0ACB\\u0ACC\\u0B02\\u0B03\\u0B3E\\u0B40\\u0B47\\u0B48\\u0B4B\\u0B4C\\u0B57\\u0BBE\\u0BBF\\u0BC1\\u0BC2\\u0BC6-\\u0BC8\\u0BCA-\\u0BCC\\u0BD7\\u0C01-\\u0C03\\u0C41-\\u0C44\\u0C82\\u0C83\\u0CBE\\u0CC0-\\u0CC4\\u0CC7\\u0CC8\\u0CCA\\u0CCB\\u0CD5\\u0CD6\\u0D02\\u0D03\\u0D3E-\\u0D40\\u0D46-\\u0D48\\u0D4A-\\u0D4C\\u0D57\\u0D82\\u0D83\\u0DCF-\\u0DD1\\u0DD8-\\u0DDF\\u0DF2\\u0DF3\\u0F3E\\u0F3F\\u0F7F\\u102B\\u102C\\u1031\\u1038\\u103B\\u103C\\u1056\\u1057\\u1062-\\u1064\\u1067-\\u106D\\u1083\\u1084\\u1087-\\u108C\\u108F\\u109A-\\u109C\\u17B6\\u17BE-\\u17C5\\u17C7\\u17C8\\u1923-\\u1926\\u1929-\\u192B\\u1930\\u1931\\u1933-\\u1938\\u19B0-\\u19C0\\u19C8\\u19C9\\u1A19-\\u1A1B\\u1A55\\u1A57\\u1A61\\u1A63\\u1A64\\u1A6D-\\u1A72\\u1B04\\u1B35\\u1B3B\\u1B3D-\\u1B41\\u1B43\\u1B44\\u1B82\\u1BA1\\u1BA6\\u1BA7\\u1BAA\\u1C24-\\u1C2B\\u1C34\\u1C35\\u1CE1\\u1CF2\\uA823\\uA824\\uA827\\uA880\\uA881\\uA8B4-\\uA8C3\\uA952\\uA953\\uA983\\uA9B4\\uA9B5\\uA9BA\\uA9BB\\uA9BD-\\uA9C0\\uAA2F\\uAA30\\uAA33\\uAA34\\uAA4D\\uAA7B\\uABE3\\uABE4\\uABE6\\uABE7\\uABE9\\uABEA\\uABEC]"),
-    connector_punctuation: new RegExp("[\\u005F\\u203F\\u2040\\u2054\\uFE33\\uFE34\\uFE4D-\\uFE4F\\uFF3F]")
-};
-
-function is_letter(code) {
-    return (code >= 97 && code <= 122)
-        || (code >= 65 && code <= 90)
-        || (code >= 0xaa && UNICODE.letter.test(String.fromCharCode(code)));
-}
-
 function is_surrogate_pair_head(code) {
     return code >= 0xd800 && code <= 0xdbff;
 }
@@ -144,36 +136,8 @@ function is_digit(code) {
     return code >= 48 && code <= 57;
 }
 
-function is_alphanumeric_char(code) {
-    return is_digit(code) || is_letter(code);
-}
-
-function is_unicode_digit(code) {
-    return UNICODE.digit.test(String.fromCharCode(code));
-}
-
-function is_unicode_combining_mark(ch) {
-    return UNICODE.non_spacing_mark.test(ch) || UNICODE.space_combining_mark.test(ch);
-}
-
-function is_unicode_connector_punctuation(ch) {
-    return UNICODE.connector_punctuation.test(ch);
-}
-
-function is_identifier_start(code) {
-    return code == 36 || code == 95 || is_letter(code);
-}
-
 function is_identifier_char(ch) {
-    var code = ch.charCodeAt(0);
-    return is_identifier_start(code)
-        || is_digit(code)
-        || code == 8204 // \u200c: zero-width non-joiner <ZWNJ>
-        || code == 8205 // \u200d: zero-width joiner <ZWJ> (in my ECMA-262 PDF, this is also 200c)
-        || is_unicode_combining_mark(ch)
-        || is_unicode_connector_punctuation(ch)
-        || is_unicode_digit(code)
-    ;
+    return !NON_IDENTIFIER_CHARS[ch];
 }
 
 function is_identifier_string(str) {
@@ -181,15 +145,13 @@ function is_identifier_string(str) {
 }
 
 function parse_js_number(num) {
-    if (RE_HEX_NUMBER.test(num)) {
-        return parseInt(num.substr(2), 16);
-    } else if (RE_OCT_NUMBER.test(num)) {
-        return parseInt(num.substr(1), 8);
-    } else {
+    var match;
+    if (match = RE_BIN_NUMBER.exec(num)) return parseInt(match[1], 2);
+    if (match = RE_HEX_NUMBER.exec(num)) return parseInt(match[1], 16);
+    if (match = RE_OCT_NUMBER.exec(num)) return parseInt(match[1], 8);
     var val = parseFloat(num);
     if (val == num) return val;
 }
-}
 
 function JS_Parse_Error(message, filename, line, col, pos) {
     this.message = message;
@@ -344,11 +306,13 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
               case (after_e = false, 46): // .
                 return (!has_dot && !has_x && !has_e) ? (has_dot = true) : false;
             }
-            return is_alphanumeric_char(code);
+            return is_digit(code) || /[_0-9a-fo]/i.test(ch);
         });
         if (prefix) num = prefix + num;
-        if (RE_OCT_NUMBER.test(num) && next_token.has_directive("use strict")) {
-            parse_error("Legacy octal literals are not allowed in strict mode");
+        if (/^0[0-7_]+$/.test(num)) {
+            if (next_token.has_directive("use strict")) parse_error("Legacy octal literals are not allowed in strict mode");
+        } else {
+            num = num.replace(has_x ? /([1-9a-f]|.0)_(?=[0-9a-f])/gi : /([1-9]|.0)_(?=[0-9])/gi, "$1");
         }
         var valid = parse_js_number(num);
         if (!isNaN(valid)) return token("num", valid);
@@ -365,13 +329,23 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
           case 118: return "\u000b";                            // \v
           case 102: return "\f";
           case 120: return String.fromCharCode(hex_bytes(2));   // \x
-          case 117 : return String.fromCharCode(hex_bytes(4)); // \u
-          case 10  : return ""; // newline
+          case 117:                                             // \u
+            if (peek() != "{") return String.fromCharCode(hex_bytes(4));
+            next();
+            var num = 0;
+            do {
+                var digit = parseInt(next(true), 16);
+                if (isNaN(digit)) parse_error("Invalid hex-character pattern in string");
+                num = num * 16 + digit;
+            } while (peek() != "}");
+            next();
+            if (num < 0x10000) return String.fromCharCode(num);
+            if (num > 0x10ffff) parse_error("Invalid character code: " + num);
+            return String.fromCharCode((num >> 10) + 0xd7c0) + String.fromCharCode((num & 0x03ff) + 0xdc00);
           case 13:                                              // \r
-            if (peek() == "\n") { // DOS newline
-                next(true, in_string);
-                return "";
-            }
+            // DOS newline
+            if (peek() == "\n") next(true, in_string);
+          case 10:  return "";                                  // \n
         }
         if (ch >= "0" && ch <= "7")
             return read_octal_escape_sequence(ch);
@@ -438,7 +412,7 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
     var skip_multiline_comment = with_eof_error("Unterminated multiline comment", function() {
         var regex_allowed = S.regex_allowed;
         var i = find("*/", true);
-        var text = S.text.substring(S.pos, i).replace(/\r\n|\r|\u2028|\u2029/g, '\n');
+        var text = S.text.substring(S.pos, i).replace(/\r\n|\r|\u2028|\u2029/g, "\n");
         // update stream position
         forward(text.length /* doesn't count \r\n as 2 char while S.pos - i does */ + 2);
         S.comments_before.push(token("comment2", text, true));
@@ -448,7 +422,7 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
 
     function read_name() {
         var backslash = false, name = "", ch, escaped = false, hex;
-        while ((ch = peek()) != null) {
+        while (ch = peek()) {
             if (!backslash) {
                 if (ch == "\\") escaped = backslash = true, next();
                 else if (is_identifier_char(ch)) name += next();
@@ -527,7 +501,16 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
 
     function handle_dot() {
         next();
-        return is_digit(peek().charCodeAt(0)) ? read_num(".") : token("punc", ".");
+        var ch = peek();
+        if (ch == ".") {
+            var op = ".";
+            do {
+                op += ".";
+                next();
+            } while (peek() == ".");
+            return token("operator", op);
+        }
+        return is_digit(ch.charCodeAt(0)) ? read_num(".") : token("punc", ".");
     }
 
     function read_word() {
@@ -587,7 +570,7 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
             if (is_digit(code)) return read_num();
             if (PUNC_CHARS[ch]) return token("punc", next());
             if (OPERATOR_CHARS[ch]) return read_operator();
-            if (code == 92 || is_identifier_start(code)) return read_word();
+            if (code == 92 || !NON_IDENTIFIER_CHARS[ch]) return read_word();
             break;
         }
         parse_error("Unexpected character '" + ch + "'");
@@ -670,13 +653,15 @@ function parse($TEXT, options) {
         input         : typeof $TEXT == "string"
                         ? tokenizer($TEXT, options.filename, options.html5_comments, options.shebang)
                         : $TEXT,
-        token         : null,
-        prev          : null,
-        peeked        : null,
-        in_function   : 0,
+        in_async      : false,
         in_directives : true,
+        in_funarg     : -1,
+        in_function   : 0,
         in_loop       : 0,
-        labels        : []
+        labels        : [],
+        peeked        : null,
+        prev          : null,
+        token         : null,
     };
 
     S.token = next();
@@ -779,7 +764,7 @@ function parse($TEXT, options) {
         }
     }
 
-    var statement = embed_tokens(function(strict_defun) {
+    var statement = embed_tokens(function() {
         handle_regexp();
         switch (S.token.type) {
           case "string":
@@ -803,9 +788,20 @@ function parse($TEXT, options) {
             return simple_statement();
 
           case "name":
+            switch (S.token.value) {
+              case "async":
+                if (is_token(peek(), "keyword", "function")) {
+                    next();
+                    next();
+                    return function_(AST_AsyncDefun);
+                }
+              case "await":
+                if (S.in_async) return simple_statement();
+              default:
                 return is_token(peek(), "punc", ":")
                     ? labeled_statement()
                     : simple_statement();
+            }
 
           case "punc":
             switch (S.token.value) {
@@ -832,6 +828,12 @@ function parse($TEXT, options) {
                 next();
                 return break_cont(AST_Break);
 
+              case "const":
+                next();
+                var node = const_();
+                semicolon();
+                return node;
+
               case "continue":
                 next();
                 return break_cont(AST_Continue);
@@ -864,9 +866,6 @@ function parse($TEXT, options) {
                 return for_();
 
               case "function":
-                if (!strict_defun && S.input.has_directive("use strict")) {
-                    croak("In strict mode code, functions can only be declared at top level or immediately within another function.");
-                }
                 next();
                 return function_(AST_Defun);
 
@@ -874,6 +873,12 @@ function parse($TEXT, options) {
                 next();
                 return if_();
 
+              case "let":
+                next();
+                var node = let_();
+                semicolon();
+                return node;
+
               case "return":
                 if (S.in_function == 0 && !options.bare_returns)
                     croak("'return' outside of function");
@@ -948,7 +953,7 @@ function parse($TEXT, options) {
         if (!(stat instanceof AST_IterationStatement)) {
             // check for `continue` that refers to this label.
             // those should be reported as syntax errors.
-            // https://github.com/mishoo/UglifyJS2/issues/287
+            // https://github.com/mishoo/UglifyJS/issues/287
             label.references.forEach(function(ref) {
                 if (ref instanceof AST_Continue) {
                     ref = ref.label.start;
@@ -988,14 +993,18 @@ function parse($TEXT, options) {
         expect("(");
         var init = null;
         if (!is("punc", ";")) {
-            init = is("keyword", "var")
+            init = is("keyword", "const")
+                ? (next(), const_(true))
+                : is("keyword", "let")
+                ? (next(), let_(true))
+                : is("keyword", "var")
                 ? (next(), var_(true))
                 : expression(true, true);
             if (is("operator", "in")) {
-                if (init instanceof AST_Var) {
+                if (init instanceof AST_Definitions) {
                     if (init.definitions.length > 1)
                         croak("Only one variable declaration allowed in for..in loop", init.start.line, init.start.col, init.start.pos);
-                } else if (!is_assignable(init)) {
+                } else if (!(is_assignable(init) || (init = to_destructured(init)) instanceof AST_Destructured)) {
                     croak("Invalid left-hand side in for..in loop", init.start.line, init.start.col, init.start.pos);
                 }
                 next();
@@ -1030,19 +1039,27 @@ function parse($TEXT, options) {
     }
 
     var function_ = function(ctor) {
-        var in_statement = ctor === AST_Defun;
-        var name = is("name") ? as_symbol(in_statement ? AST_SymbolDefun : AST_SymbolLambda) : null;
-        if (in_statement && !name)
-            expect_token("name");
+        var was_async = S.in_async;
+        var name;
+        if (ctor === AST_AsyncDefun) {
+            name = as_symbol(AST_SymbolDefun);
+            S.in_async = true;
+        } else if (ctor === AST_Defun) {
+            name = as_symbol(AST_SymbolDefun);
+            S.in_async = false;
+        } else {
+            S.in_async = ctor === AST_AsyncFunction;
+            name = as_symbol(AST_SymbolLambda, true);
+        }
         if (name && ctor !== AST_Accessor && !(name instanceof AST_SymbolDeclaration))
             unexpected(prev());
         expect("(");
-        var argnames = [];
-        for (var first = true; !is("punc", ")");) {
-            if (first) first = false; else expect(",");
-            argnames.push(as_symbol(AST_SymbolFunarg));
-        }
-        next();
+        var was_funarg = S.in_funarg;
+        S.in_funarg = S.in_function;
+        var argnames = expr_list(")", !options.strict, false, function() {
+            return maybe_destructured(AST_SymbolFunarg);
+        });
+        S.in_funarg = was_funarg;
         var loop = S.in_loop;
         var labels = S.labels;
         ++S.in_function;
@@ -1050,7 +1067,7 @@ function parse($TEXT, options) {
         S.input.push_directives_stack();
         S.in_loop = 0;
         S.labels = [];
-        var body = block_(true);
+        var body = block_();
         if (S.input.has_directive("use strict")) {
             if (name) strict_verify_symbol(name);
             argnames.forEach(strict_verify_symbol);
@@ -1059,6 +1076,7 @@ function parse($TEXT, options) {
         --S.in_function;
         S.in_loop = loop;
         S.labels = labels;
+        S.in_async = was_async;
         return new ctor({
             name: name,
             argnames: argnames,
@@ -1079,12 +1097,12 @@ function parse($TEXT, options) {
         });
     }
 
-    function block_(strict_defun) {
+    function block_() {
         expect("{");
         var a = [];
         while (!is("punc", "}")) {
             if (is("eof")) expect_token("punc", "}");
-            a.push(statement(strict_defun));
+            a.push(statement());
         }
         next();
         return a;
@@ -1092,7 +1110,7 @@ function parse($TEXT, options) {
 
     function switch_body_() {
         expect("{");
-        var a = [], cur = null, branch = null, tmp;
+        var a = [], branch, cur, default_branch, tmp;
         while (!is("punc", "}")) {
             if (is("eof")) expect_token("punc", "}");
             if (is("keyword", "case")) {
@@ -1107,12 +1125,14 @@ function parse($TEXT, options) {
                 expect(":");
             } else if (is("keyword", "default")) {
                 if (branch) branch.end = prev();
+                if (default_branch) croak("More than one default clause in switch statement");
                 cur = [];
                 branch = new AST_Default({
                     start : (tmp = S.token, next(), expect(":"), tmp),
                     body  : cur
                 });
                 a.push(branch);
+                default_branch = branch;
             } else {
                 if (!cur) unexpected();
                 cur.push(statement());
@@ -1128,9 +1148,12 @@ function parse($TEXT, options) {
         if (is("keyword", "catch")) {
             var start = S.token;
             next();
-            expect("(");
-            var name = as_symbol(AST_SymbolCatch);
+            var name = null;
+            if (is("punc", "(")) {
+                next();
+                name = as_symbol(AST_SymbolCatch);
                 expect(")");
+            }
             bcatch = new AST_Catch({
                 start   : start,
                 argname : name,
@@ -1156,13 +1179,22 @@ function parse($TEXT, options) {
         });
     }
 
-    function vardefs(no_in) {
+    function vardefs(type, no_in) {
         var a = [];
         for (;;) {
+            var start = S.token;
+            var name = maybe_destructured(type);
+            var value = null;
+            if (is("operator", "=")) {
+                next();
+                value = expression(false, no_in);
+            } else if (!no_in && (type === AST_SymbolConst || name instanceof AST_Destructured)) {
+                croak("Missing initializer in declaration");
+            }
             a.push(new AST_VarDef({
-                start : S.token,
-                name  : as_symbol(AST_SymbolVar),
-                value : is("operator", "=") ? (next(), expression(false, no_in)) : null,
+                start : start,
+                name  : name,
+                value : value,
                 end   : prev()
             }));
             if (!is("punc", ","))
@@ -1172,10 +1204,26 @@ function parse($TEXT, options) {
         return a;
     }
 
+    var const_ = function(no_in) {
+        return new AST_Const({
+            start       : prev(),
+            definitions : vardefs(AST_SymbolConst, no_in),
+            end         : prev()
+        });
+    };
+
+    var let_ = function(no_in) {
+        return new AST_Let({
+            start       : prev(),
+            definitions : vardefs(AST_SymbolLet, no_in),
+            end         : prev()
+        });
+    };
+
     var var_ = function(no_in) {
         return new AST_Var({
             start       : prev(),
-            definitions : vardefs(no_in),
+            definitions : vardefs(AST_SymbolVar, no_in),
             end         : prev()
         });
     };
@@ -1186,7 +1234,7 @@ function parse($TEXT, options) {
         var newexp = expr_atom(false), args;
         if (is("punc", "(")) {
             next();
-            args = expr_list(")");
+            args = expr_list(")", !options.strict);
         } else {
             args = [];
         }
@@ -1204,7 +1252,7 @@ function parse($TEXT, options) {
         var tok = S.token, ret;
         switch (tok.type) {
           case "name":
-            ret = _make_symbol(AST_SymbolRef);
+            ret = _make_symbol(AST_SymbolRef, tok);
             break;
           case "num":
             ret = new AST_Number({ start: tok, end: tok, value: tok.value });
@@ -1278,9 +1326,16 @@ function parse($TEXT, options) {
             }
             unexpected();
         }
-        if (is("keyword", "function")) {
+        var ctor;
+        if (is("name", "async") && is_token(peek(), "keyword", "function")) {
             next();
-            var func = function_(AST_Function);
+            ctor = AST_AsyncFunction;
+        } else if (is("keyword", "function")) {
+            ctor = AST_Function;
+        }
+        if (ctor) {
+            next();
+            var func = function_(ctor);
             func.start = start;
             func.end = prev();
             return subscripts(func, allow_calls);
@@ -1291,15 +1346,22 @@ function parse($TEXT, options) {
         unexpected();
     };
 
-    function expr_list(closing, allow_trailing_comma, allow_empty) {
+    function expr_list(closing, allow_trailing_comma, allow_empty, parser) {
+        if (!parser) parser = expression;
         var first = true, a = [];
         while (!is("punc", closing)) {
             if (first) first = false; else expect(",");
             if (allow_trailing_comma && is("punc", closing)) break;
-            if (is("punc", ",") && allow_empty) {
+            if (allow_empty && is("punc", ",")) {
                 a.push(new AST_Hole({ start: S.token, end: S.token }));
+            } else if (parser === expression && is("operator", "...")) {
+                a.push(new AST_Spread({
+                    start: S.token,
+                    expression: (next(), parser()),
+                    end: prev(),
+                }));
             } else {
-                a.push(expression(false));
+                a.push(parser());
             }
         }
         next();
@@ -1322,51 +1384,71 @@ function parse($TEXT, options) {
         var first = true, a = [];
         while (!is("punc", "}")) {
             if (first) first = false; else expect(",");
-            if (!options.strict && is("punc", "}"))
             // allow trailing comma
-                break;
+            if (!options.strict && is("punc", "}")) break;
             var start = S.token;
-            var type = start.type;
-            var name = as_property_name();
-            if (type == "name" && !is("punc", ":")) {
-                var key = new AST_SymbolAccessor({
-                    start: S.token,
-                    name: "" + as_property_name(),
-                    end: prev()
-                });
-                if (name == "get") {
+            if (is("operator", "...")) {
+                next();
+                a.push(new AST_Spread({
+                    start: start,
+                    expression: expression(false),
+                    end: prev(),
+                }));
+                continue;
+            }
+            var key = as_property_key();
+            if (is("punc", "(")) {
+                var func_start = S.token;
+                var func = function_(AST_Function);
+                func.start = func_start;
+                func.end = prev();
+                a.push(new AST_ObjectKeyVal({
+                    start: start,
+                    key: key,
+                    value: func,
+                    end: prev(),
+                }));
+                continue;
+            }
+            if (!is("punc", ":") && start.type == "name") switch (key) {
+              case "get":
                 a.push(new AST_ObjectGetter({
                     start: start,
-                        key   : key,
+                    key: as_property_key(),
                     value: create_accessor(),
-                        end   : prev()
+                    end: prev(),
                 }));
                 continue;
-                }
-                if (name == "set") {
+              case "set":
                 a.push(new AST_ObjectSetter({
                     start: start,
-                        key   : key,
+                    key: as_property_key(),
                     value: create_accessor(),
-                        end   : prev()
+                    end: prev(),
+                }));
+                continue;
+              default:
+                a.push(new AST_ObjectKeyVal({
+                    start: start,
+                    key: key,
+                    value: _make_symbol(AST_SymbolRef, start),
+                    end: prev(),
                 }));
                 continue;
-                }
             }
             expect(":");
             a.push(new AST_ObjectKeyVal({
                 start: start,
-                quote : start.quote,
-                key   : "" + name,
+                key: key,
                 value: expression(false),
-                end   : prev()
+                end: prev(),
             }));
         }
         next();
         return new AST_Object({ properties: a });
     });
 
-    function as_property_name() {
+    function as_property_key() {
         var tmp = S.token;
         switch (tmp.type) {
           case "operator":
@@ -1377,7 +1459,13 @@ function parse($TEXT, options) {
           case "keyword":
           case "atom":
             next();
-            return tmp.value;
+            return "" + tmp.value;
+          case "punc":
+            if (tmp.value != "[") unexpected();
+            next();
+            var key = expression(false);
+            expect("]");
+            return key;
           default:
             unexpected();
         }
@@ -1390,12 +1478,13 @@ function parse($TEXT, options) {
         return name;
     }
 
-    function _make_symbol(type) {
-        var name = S.token.value;
-        return new (name == "this" ? AST_This : type)({
-            name  : String(name),
-            start : S.token,
-            end   : S.token
+    function _make_symbol(type, token) {
+        var name = token.value;
+        if (name === "await" && S.in_async) unexpected(token);
+        return new (name === "this" ? AST_This : type)({
+            name: "" + name,
+            start: token,
+            end: token,
         });
     }
 
@@ -1409,7 +1498,7 @@ function parse($TEXT, options) {
             if (!noerror) croak("Name expected");
             return null;
         }
-        var sym = _make_symbol(type);
+        var sym = _make_symbol(type, S.token);
         if (S.input.has_directive("use strict") && sym instanceof AST_SymbolDeclaration) {
             strict_verify_symbol(sym);
         }
@@ -1417,6 +1506,54 @@ function parse($TEXT, options) {
         return sym;
     }
 
+    function maybe_destructured(type) {
+        var start = S.token;
+        if (is("punc", "[")) {
+            next();
+            return new AST_DestructuredArray({
+                start: start,
+                elements: expr_list("]", !options.strict, true, function() {
+                    return maybe_destructured(type);
+                }),
+                end: prev(),
+            });
+        }
+        if (is("punc", "{")) {
+            next();
+            var first = true, a = [];
+            while (!is("punc", "}")) {
+                if (first) first = false; else expect(",");
+                // allow trailing comma
+                if (!options.strict && is("punc", "}")) break;
+                var key_start = S.token;
+                var key = as_property_key();
+                if (!is("punc", ":") && key_start.type == "name") {
+                    a.push(new AST_DestructuredKeyVal({
+                        start: key_start,
+                        key: key,
+                        value: _make_symbol(type, key_start),
+                        end: prev(),
+                    }));
+                    continue;
+                }
+                expect(":");
+                a.push(new AST_DestructuredKeyVal({
+                    start: key_start,
+                    key: key,
+                    value: maybe_destructured(type),
+                    end: prev(),
+                }));
+            }
+            next();
+            return new AST_DestructuredObject({
+                start: start,
+                properties: a,
+                end: prev(),
+            });
+        }
+        return as_symbol(type);
+    }
+
     function mark_pure(call) {
         var start = call.start;
         var comments = start.comments_before;
@@ -1457,7 +1594,7 @@ function parse($TEXT, options) {
             var call = new AST_Call({
                 start      : start,
                 expression : expr,
-                args       : expr_list(")"),
+                args       : expr_list(")", !options.strict),
                 end        : prev()
             });
             mark_pure(call);
@@ -1466,17 +1603,17 @@ function parse($TEXT, options) {
         return expr;
     };
 
-    var maybe_unary = function(allow_calls) {
+    function maybe_unary() {
         var start = S.token;
         if (is("operator") && UNARY_PREFIX[start.value]) {
             next();
             handle_regexp();
-            var ex = make_unary(AST_UnaryPrefix, start, maybe_unary(allow_calls));
+            var ex = make_unary(AST_UnaryPrefix, start, maybe_await());
             ex.start = start;
             ex.end = prev();
             return ex;
         }
-        var val = expr_atom(allow_calls);
+        var val = expr_atom(true);
         while (is("operator") && UNARY_POSTFIX[S.token.value] && !has_newline_before(S.token)) {
             val = make_unary(AST_UnaryPostfix, S.token, val);
             val.start = start;
@@ -1484,7 +1621,7 @@ function parse($TEXT, options) {
             next();
         }
         return val;
-    };
+    }
 
     function make_unary(ctor, token, expr) {
         var op = token.value;
@@ -1502,13 +1639,26 @@ function parse($TEXT, options) {
         return new ctor({ operator: op, expression: expr });
     }
 
+    function maybe_await() {
+        var start = S.token;
+        if (!(S.in_async && is("name", "await"))) return maybe_unary();
+        if (S.in_funarg === S.in_function) croak("Invalid use of await in function argument");
+        S.input.context().regex_allowed = true;
+        next();
+        return new AST_Await({
+            start: start,
+            expression: maybe_await(),
+            end: prev(),
+        });
+    }
+
     var expr_op = function(left, min_prec, no_in) {
         var op = is("operator") ? S.token.value : null;
         if (op == "in" && no_in) op = null;
         var prec = op != null ? PRECEDENCE[op] : null;
         if (prec != null && prec > min_prec) {
             next();
-            var right = expr_op(maybe_unary(true), prec, no_in);
+            var right = expr_op(maybe_await(), prec, no_in);
             return expr_op(new AST_Binary({
                 start    : left.start,
                 left     : left,
@@ -1521,7 +1671,7 @@ function parse($TEXT, options) {
     };
 
     function expr_ops(no_in) {
-        return expr_op(maybe_unary(true), 0, no_in);
+        return expr_op(maybe_await(), 0, no_in);
     }
 
     var maybe_conditional = function(no_in) {
@@ -1546,11 +1696,43 @@ function parse($TEXT, options) {
         return expr instanceof AST_PropAccess || expr instanceof AST_SymbolRef;
     }
 
+    function to_destructured(node) {
+        if (node instanceof AST_Array) {
+            var elements = node.elements.map(to_destructured);
+            return all(elements, function(node) {
+                return node instanceof AST_Destructured || node instanceof AST_Hole || is_assignable(node);
+            }) ? new AST_DestructuredArray({
+                start: node.start,
+                elements: elements,
+                end: node.end,
+            }) : node;
+        }
+        if (!(node instanceof AST_Object)) return node;
+        var props = [];
+        for (var i = 0; i < node.properties.length; i++) {
+            var prop = node.properties[i];
+            if (!(prop instanceof AST_ObjectKeyVal)) return node;
+            var value = to_destructured(prop.value);
+            if (!(value instanceof AST_Destructured || is_assignable(value))) return node;
+            props.push(new AST_DestructuredKeyVal({
+                start: prop.start,
+                key: prop.key,
+                value: value,
+                end: prop.end,
+            }));
+        }
+        return new AST_DestructuredObject({
+            start: node.start,
+            properties: props,
+            end: node.end,
+        });
+    }
+
     var maybe_assign = function(no_in) {
         var start = S.token;
         var left = maybe_conditional(no_in), val = S.token.value;
         if (is("operator") && ASSIGNMENT[val]) {
-            if (is_assignable(left)) {
+            if (is_assignable(left) || val == "=" && (left = to_destructured(left)) instanceof AST_Destructured) {
                 next();
                 return new AST_Assign({
                     start    : start,
@@ -1598,7 +1780,7 @@ function parse($TEXT, options) {
         var body = [];
         S.input.push_directives_stack();
         while (!is("eof"))
-            body.push(statement(true));
+            body.push(statement());
         S.input.pop_directives_stack();
         var end = prev();
         var toplevel = options.toplevel;

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",
@@ -67,19 +68,21 @@ function find_builtins(reserved) {
     ].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) {
-        push_uniq(reserved, name);
-    }
+        names.push(name);
     }
+}();
 
 function reserve_quoted_keys(ast, reserved) {
     ast.walk(new TreeWalker(function(node) {
-        if (node instanceof AST_ObjectKeyVal && node.quote) {
-            add(node.key);
+        if (node instanceof AST_ObjectProperty) {
+            if (node.start && node.start.quote) add(node.key);
         } else if (node instanceof AST_Sub) {
             addStrings(node.property, add);
         }
@@ -91,17 +94,14 @@ function reserve_quoted_keys(ast, reserved) {
 }
 
 function addStrings(node, add) {
-    node.walk(new TreeWalker(function(node) {
-        if (node instanceof AST_Sequence) {
+    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);
-        } else if (node instanceof AST_Conditional) {
-            addStrings(node.consequent, add);
-            addStrings(node.alternative, add);
     }
-        return true;
-    }));
 }
 
 function mangle_properties(ast, options) {
@@ -110,21 +110,21 @@ function mangle_properties(ast, options) {
         cache: null,
         debug: false,
         keep_quoted: false,
-        only_cache: false,
         regex: null,
         reserved: null,
     }, true);
 
-    var reserved = options.reserved;
-    if (!Array.isArray(reserved)) reserved = [];
-    if (!options.builtins) find_builtins(reserved);
+    var reserved = Object.create(options.builtins ? null : builtins);
+    if (Array.isArray(options.reserved)) options.reserved.forEach(function(name) {
+        reserved[name] = true;
+    });
 
     var cname = -1;
     var cache;
     if (options.cache) {
         cache = options.cache.props;
-        cache.each(function(mangled_name) {
-            push_uniq(reserved, mangled_name);
+        cache.each(function(name) {
+            reserved[name] = true;
         });
     } else {
         cache = new Dictionary();
@@ -139,62 +139,86 @@ function mangle_properties(ast, options) {
     var debug_suffix;
     if (debug) debug_suffix = options.debug === true ? "" : options.debug;
 
-    var names_to_mangle = [];
-    var unmangleable = [];
+    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);
-        } else if (node instanceof AST_ObjectProperty) {
-            // setter or getter, since KeyVal is handled above
-            add(node.key.name);
+        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_Dot) {
             add(node.property);
+        } else if (node instanceof AST_ObjectProperty) {
+            if (typeof node.key == "string") add(node.key);
         } else if (node instanceof AST_Sub) {
             addStrings(node.property, add);
-        } else if (node instanceof AST_Call
-            && node.expression.print_to_string() == "Object.defineProperty") {
-            addStrings(node.args[1], add);
         }
     }));
 
-    // step 2: transform the tree, renaming properties
-    return ast.transform(new TreeTransformer(function(node) {
-        if (node instanceof AST_ObjectKeyVal) {
-            node.key = mangle(node.key);
-        } else if (node instanceof AST_ObjectProperty) {
-            // setter or getter
-            node.key.name = mangle(node.key.name);
+    // 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_Dot) {
             node.property = mangle(node.property);
-        } else if (!options.keep_quoted && node instanceof AST_Sub) {
-            node.property = mangleStrings(node.property);
-        } else if (node instanceof AST_Call
-            && node.expression.print_to_string() == "Object.defineProperty") {
-            node.args[1] = mangleStrings(node.args[1]);
+        } 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);
         }
     }));
 
     // 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.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 (reserved[name]) return false;
         if (regex && !regex.test(name)) return false;
-        if (reserved.indexOf(name) >= 0) return false;
-        return cache.has(name) || names_to_mangle.indexOf(name) >= 0;
+        return cache.has(name) || names_to_mangle[name];
     }
 
     function add(name) {
-        if (can_mangle(name)) push_uniq(names_to_mangle, name);
-        if (!should_mangle(name)) push_uniq(unmangleable, name);
+        if (can_mangle(name)) names_to_mangle[name] = true;
+        if (!should_mangle(name)) unmangleable[name] = true;
     }
 
     function mangle(name) {
@@ -218,17 +242,13 @@ function mangle_properties(ast, options) {
     }
 
     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]);
+            mangleStrings(node.expressions.tail_node());
         } 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;
-        }));
+            mangleStrings(node.consequent);
+            mangleStrings(node.alternative);
+        }
     }
 }

lib/scope.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -43,24 +43,53 @@
 
 "use strict";
 
-function SymbolDef(scope, orig, init) {
+function SymbolDef(id, scope, orig, init) {
+    this.eliminated = 0;
+    this.global = false;
+    this.id = id;
+    this.init = init;
+    this.lambda = orig instanceof AST_SymbolLambda;
+    this.mangled_name = null;
     this.name = orig.name;
     this.orig = [ orig ];
-    this.init = init;
-    this.eliminated = 0;
-    this.scope = scope;
     this.references = [];
     this.replaced = 0;
-    this.global = false;
-    this.mangled_name = null;
+    this.scope = scope;
     this.undeclared = false;
-    this.id = SymbolDef.next_id++;
-    this.lambda = orig instanceof AST_SymbolLambda;
 }
 
-SymbolDef.next_id = 1;
-
 SymbolDef.prototype = {
+    forEach: function(fn) {
+        this.orig.forEach(fn);
+        this.references.forEach(fn);
+    },
+    mangle: function(options) {
+        var cache = options.cache && options.cache.props;
+        if (this.global && cache && cache.has(this.name)) {
+            this.mangled_name = cache.get(this.name);
+        } else if (!this.mangled_name && !this.unmangleable(options)) {
+            var def = this.redefined();
+            if (def) {
+                this.mangled_name = def.mangled_name || def.name;
+            } else {
+                this.mangled_name = next_mangled_name(this, options);
+            }
+            if (this.global && cache) {
+                cache.set(this.name, this.mangled_name);
+            }
+        }
+    },
+    redefined: function() {
+        var scope = this.defun;
+        if (!scope) return;
+        var name = this.name;
+        var def = scope.variables.get(name)
+            || scope instanceof AST_Toplevel && scope.globals.get(name)
+            || this.orig[0] instanceof AST_SymbolConst && find_if(function(def) {
+                return def.name == name;
+            }, scope.enclosed);
+        if (def && def !== this) return def.redefined() || def;
+    },
     unmangleable: function(options) {
         return this.global && !options.toplevel
             || this.undeclared
@@ -69,25 +98,6 @@ SymbolDef.prototype = {
                 && (this.orig[0] instanceof AST_SymbolLambda
                     || this.orig[0] instanceof AST_SymbolDefun);
     },
-    mangle: function(options) {
-        var cache = options.cache && options.cache.props;
-        if (this.global && cache && cache.has(this.name)) {
-            this.mangled_name = cache.get(this.name);
-        } else if (!this.mangled_name && !this.unmangleable(options)) {
-            var def;
-            if (def = this.redefined()) {
-                this.mangled_name = def.mangled_name || def.name;
-            } else {
-                this.mangled_name = next_mangled_name(this.scope, options, this);
-            }
-            if (this.global && cache) {
-                cache.set(this.name, this.mangled_name);
-            }
-        }
-    },
-    redefined: function() {
-        return this.defun && this.defun.variables.get(this.name);
-    }
 };
 
 AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
@@ -98,30 +108,46 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
 
     // pass 1: setup scope chaining and handle definitions
     var self = this;
-    var scope = self.parent_scope = null;
     var defun = null;
+    var next_def_id = 0;
+    var scope = self.parent_scope = null;
     var tw = new TreeWalker(function(node, descend) {
-        if (node instanceof AST_Catch) {
-            var save_scope = scope;
-            scope = new AST_Scope(node);
-            scope.init_scope_vars(save_scope);
-            descend();
-            scope = save_scope;
+        if (is_defun(node)) {
+            node.name.walk(tw);
+            walk_scope(function() {
+                node.argnames.forEach(function(argname) {
+                    argname.walk(tw);
+                });
+                walk_body(node, tw);
+            });
             return true;
         }
-        if (node instanceof AST_Scope) {
-            node.init_scope_vars(scope);
-            var save_scope = scope;
-            var save_defun = defun;
-            defun = scope = node;
+        if (node instanceof AST_SwitchBranch) {
+            node.init_vars(scope);
             descend();
-            scope = save_scope;
-            defun = save_defun;
+            return true;
+        }
+        if (node instanceof AST_Try) {
+            walk_scope(function() {
+                walk_body(node, tw);
+            });
+            if (node.bcatch) node.bcatch.walk(tw);
+            if (node.bfinally) node.bfinally.walk(tw);
             return true;
         }
         if (node instanceof AST_With) {
-            for (var s = scope; s; s = s.parent_scope) s.uses_with = true;
-            return;
+            var s = scope;
+            do {
+                s = s.resolve();
+                if (s.uses_with) break;
+                s.uses_with = true;
+            } while (s = s.parent_scope);
+            walk_scope(descend);
+            return true;
+        }
+        if (node instanceof AST_BlockScope) {
+            walk_scope(descend);
+            return true;
         }
         if (node instanceof AST_Symbol) {
             node.scope = scope;
@@ -130,59 +156,70 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
             node.thedef = node;
             node.references = [];
         }
-        if (node instanceof AST_SymbolDefun) {
-            // This should be defined in the parent scope, as we encounter the
-            // AST_Defun node before getting to its AST_Symbol.
-            (node.scope = defun.parent_scope.resolve()).def_function(node, defun);
+        if (node instanceof AST_SymbolCatch) {
+            scope.def_variable(node).defun = defun;
+        } else if (node instanceof AST_SymbolConst) {
+            scope.def_variable(node).defun = defun;
+        } else if (node instanceof AST_SymbolDefun) {
+            defun.def_function(node, tw.parent());
+            entangle(defun, scope);
+        } else if (node instanceof AST_SymbolFunarg) {
+            defun.def_variable(node);
+            entangle(defun, scope);
         } else if (node instanceof AST_SymbolLambda) {
             var def = defun.def_function(node, node.name == "arguments" ? undefined : defun);
             if (options.ie8) def.defun = defun.parent_scope.resolve();
+        } else if (node instanceof AST_SymbolLet) {
+            scope.def_variable(node);
         } else if (node instanceof AST_SymbolVar) {
-            defun.def_variable(node, node.TYPE == "SymbolVar" ? null : undefined);
-            if (defun !== scope) {
+            defun.def_variable(node, null);
+            entangle(defun, scope);
+        }
+
+        function walk_scope(descend) {
+            node.init_vars(scope);
+            var save_defun = defun;
+            var save_scope = scope;
+            if (node instanceof AST_Scope) defun = node;
+            scope = node;
+            descend();
+            scope = save_scope;
+            defun = save_defun;
+        }
+
+        function entangle(defun, scope) {
+            if (defun === scope) return;
             node.mark_enclosed(options);
-                var def = scope.find_variable(node);
-                if (node.thedef !== def) {
+            var def = scope.find_variable(node.name);
+            if (node.thedef === def) return;
             node.thedef = def;
-                }
-                node.reference(options);
-            }
-        } else if (node instanceof AST_SymbolCatch) {
-            scope.def_variable(node).defun = defun;
+            def.orig.push(node);
+            node.mark_enclosed(options);
         }
     });
+    self.make_def = function(orig, init) {
+        return new SymbolDef(++next_def_id, this, orig, init);
+    };
     self.walk(tw);
 
     // pass 2: find back references and eval
     self.globals = new Dictionary();
+    var in_arg = [];
     var tw = new TreeWalker(function(node) {
+        if (node instanceof AST_Lambda) {
+            in_arg.push(node);
+            node.argnames.forEach(function(argname) {
+                argname.walk(tw);
+            });
+            in_arg.pop();
+            walk_body(node, tw);
+            return true;
+        }
         if (node instanceof AST_LoopControl) {
             if (node.label) node.label.thedef.references.push(node);
             return true;
         }
-        if (node instanceof AST_SymbolRef) {
-            var name = node.name;
-            var sym = node.scope.find_variable(name);
-            if (!sym) {
-                sym = self.def_global(node);
-            } else if (sym.scope instanceof AST_Lambda && name == "arguments") {
-                sym.scope.uses_arguments = true;
-            }
-            if (name == "eval") {
-                var parent = tw.parent();
-                if (parent.TYPE == "Call" && parent.expression === node) {
-                    for (var s = node.scope; s && !s.uses_eval; s = s.parent_scope) {
-                        s.uses_eval = true;
-                    }
-                } else if (sym.undeclared) {
-                    self.uses_eval = true;
-                }
-            }
-            node.thedef = sym;
-            node.reference(options);
-            return true;
-        }
-        // ensure mangling works if catch reuses a scope variable
+        // ensure mangling works if `catch` reuses a scope variable
         if (node instanceof AST_SymbolCatch) {
             var def = node.definition().redefined();
             if (def) for (var s = node.scope; s; s = s.parent_scope) {
@@ -191,6 +228,51 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
             }
             return true;
         }
+        // ensure compression works if `const` reuses a scope variable
+        if (node instanceof AST_SymbolConst) {
+            var redef = node.definition().redefined();
+            if (redef) redef.const_redefs = true;
+            return true;
+        }
+        if (node instanceof AST_SymbolRef) {
+            var name = node.name;
+            var sym = node.scope.find_variable(name);
+            for (var i = in_arg.length; i > 0 && sym;) {
+                i = in_arg.lastIndexOf(sym.scope, i - 1);
+                if (i < 0) break;
+                var decl = sym.orig[0];
+                if (decl instanceof AST_SymbolFunarg || decl instanceof AST_SymbolLambda) {
+                    node.in_arg = true;
+                    break;
+                }
+                sym = sym.scope.parent_scope.find_variable(name);
+            }
+            if (!sym) {
+                sym = self.def_global(node);
+            } else if (name == "arguments" && sym.scope instanceof AST_Lambda) {
+                if (!(tw.parent() instanceof AST_PropAccess)) {
+                    sym.scope.uses_arguments = "d";
+                } else if (!sym.scope.uses_arguments) {
+                    sym.scope.uses_arguments = true;
+                }
+            }
+            if (name == "eval") {
+                var parent = tw.parent();
+                if (parent.TYPE == "Call" && parent.expression === node) {
+                    var s = node.scope;
+                    do {
+                        s = s.resolve();
+                        if (s.uses_eval) break;
+                        s.uses_eval = true;
+                    } while (s = s.parent_scope);
+                } else if (sym.undeclared) {
+                    self.uses_eval = true;
+                }
+            }
+            node.thedef = sym;
+            node.reference(options);
+            return true;
+        }
     });
     self.walk(tw);
 
@@ -219,10 +301,13 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
     function redefine(node, scope) {
         var name = node.name;
         var old_def = node.thedef;
+        if (!all(old_def.orig, function(sym) {
+            return !(sym instanceof AST_SymbolConst || sym instanceof AST_SymbolLet);
+        })) return;
         var new_def = scope.find_variable(name);
         if (new_def) {
-            var redef;
-            while (redef = new_def.redefined()) new_def = redef;
+            var redef = new_def.redefined();
+            if (redef) new_def = redef;
         } else {
             new_def = self.globals.get(name);
         }
@@ -231,7 +316,9 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
         } else {
             new_def = scope.def_variable(node);
         }
-        old_def.orig.concat(old_def.references).forEach(function(node) {
+        old_def.defun = new_def.scope;
+        old_def.forEach(function(node) {
+            node.redef = true;
             node.thedef = new_def;
             node.reference(options);
         });
@@ -245,7 +332,7 @@ AST_Toplevel.DEFMETHOD("def_global", function(node) {
     if (globals.has(name)) {
         return globals.get(name);
     } else {
-        var g = new SymbolDef(this, node);
+        var g = this.make_def(node);
         g.undeclared = true;
         g.global = true;
         globals.set(name, g);
@@ -253,24 +340,35 @@ AST_Toplevel.DEFMETHOD("def_global", function(node) {
     }
 });
 
-AST_Scope.DEFMETHOD("init_scope_vars", function(parent_scope) {
-    this.variables = new Dictionary();  // map name to AST_SymbolVar (variables defined in this scope; includes functions)
-    this.functions = new Dictionary();  // map name to AST_SymbolDefun (functions defined in this scope)
-    this.uses_with = false;             // will be set to true if this or some nested scope uses the `with` statement
-    this.uses_eval = false;             // will be set to true if this or nested scope uses the global `eval`
-    this.parent_scope = parent_scope;   // the parent scope
-    this.enclosed = [];                 // a list of variables from this or outer scope(s) that are referenced from this or inner scopes
-    this.cname = -1;                    // the current index for mangling functions/variables
-});
+function init_block_vars(scope, parent) {
+    scope.enclosed = [];                            // variables from this or outer scope(s) that are referenced from this or inner scopes
+    scope.parent_scope = parent;                    // the parent scope (null if this is the top level)
+    scope.functions = new Dictionary();             // map name to AST_SymbolDefun (functions defined in this scope)
+    scope.variables = new Dictionary();             // map name to AST_SymbolVar (variables defined in this scope; includes functions)
+    if (parent) scope.make_def = parent.make_def;   // top-level tracking of SymbolDef instances
+}
 
-AST_Lambda.DEFMETHOD("init_scope_vars", function() {
-    AST_Scope.prototype.init_scope_vars.apply(this, arguments);
+function init_scope_vars(scope, parent) {
+    init_block_vars(scope, parent);
+    scope.uses_eval = false;                        // will be set to true if this or nested scope uses the global `eval`
+    scope.uses_with = false;                        // will be set to true if this or some nested scope uses the `with` statement
+}
+
+AST_BlockScope.DEFMETHOD("init_vars", function(parent_scope) {
+    init_block_vars(this, parent_scope);
+});
+AST_Scope.DEFMETHOD("init_vars", function(parent_scope) {
+    init_scope_vars(this, parent_scope);
+});
+AST_Lambda.DEFMETHOD("init_vars", function(parent_scope) {
+    init_scope_vars(this, parent_scope);
     this.uses_arguments = false;
     this.def_variable(new AST_SymbolFunarg({
         name: "arguments",
         start: this.start,
-        end: this.end
+        end: this.end,
     }));
+    return this;
 });
 
 AST_Symbol.DEFMETHOD("mark_enclosed", function(options) {
@@ -291,43 +389,37 @@ AST_Symbol.DEFMETHOD("reference", function(options) {
     this.mark_enclosed(options);
 });
 
-AST_Scope.DEFMETHOD("find_variable", function(name) {
-    if (name instanceof AST_Symbol) name = name.name;
+AST_BlockScope.DEFMETHOD("find_variable", function(name) {
     return this.variables.get(name)
-        || (this.parent_scope && this.parent_scope.find_variable(name));
+        || this.parent_scope && this.parent_scope.find_variable(name);
 });
 
-AST_Scope.DEFMETHOD("def_function", function(symbol, init) {
+AST_BlockScope.DEFMETHOD("def_function", function(symbol, init) {
     var def = this.def_variable(symbol, init);
-    if (!def.init || def.init instanceof AST_Defun) def.init = init;
+    if (!def.init || is_defun(def.init)) def.init = init;
     this.functions.set(symbol.name, def);
     return def;
 });
 
-AST_Scope.DEFMETHOD("def_variable", function(symbol, init) {
+AST_BlockScope.DEFMETHOD("def_variable", function(symbol, init) {
     var def = this.variables.get(symbol.name);
     if (def) {
         def.orig.push(symbol);
-        if (def.init instanceof AST_Function) def.init = init;
+        if (is_function(def.init)) def.init = init;
     } else {
-        def = new SymbolDef(this, symbol, init);
+        def = this.make_def(symbol, init);
         this.variables.set(symbol.name, def);
         def.global = !this.parent_scope;
     }
     return symbol.thedef = def;
 });
 
-AST_Lambda.DEFMETHOD("resolve", return_this);
-AST_Scope.DEFMETHOD("resolve", function() {
-    return this.parent_scope.resolve();
-});
-AST_Toplevel.DEFMETHOD("resolve", return_this);
-
 function names_in_use(scope, options) {
     var names = scope.names_in_use;
     if (!names) {
-        scope.names_in_use = names = Object.create(scope.mangled_names || null);
+        scope.cname = -1;
         scope.cname_holes = [];
+        scope.names_in_use = names = Object.create(null);
         var cache = options.cache && options.cache.props;
         scope.enclosed.forEach(function(def) {
             if (def.unmangleable(options)) names[def.name] = true;
@@ -339,12 +431,13 @@ function names_in_use(scope, options) {
     return names;
 }
 
-function next_mangled_name(scope, options, def) {
+function next_mangled_name(def, options) {
+    var scope = def.scope;
     var in_use = names_in_use(scope, options);
     var holes = scope.cname_holes;
     var names = Object.create(null);
     var scopes = [ scope ];
-    def.references.forEach(function(sym) {
+    def.forEach(function(sym) {
         var scope = sym.scope;
         do {
             if (scopes.indexOf(scope) < 0) {
@@ -360,7 +453,7 @@ function next_mangled_name(scope, options, def) {
         name = base54(holes[i]);
         if (names[name]) continue;
         holes.splice(i, 1);
-        scope.names_in_use[name] = true;
+        in_use[name] = true;
         return name;
     }
     while (true) {
@@ -369,7 +462,7 @@ function next_mangled_name(scope, options, def) {
         if (!names[name]) break;
         holes.push(scope.cname);
     }
-    scope.names_in_use[name] = true;
+    in_use[name] = true;
     return name;
 }
 
@@ -381,18 +474,10 @@ AST_Symbol.DEFMETHOD("unmangleable", function(options) {
 // labels are always mangleable
 AST_Label.DEFMETHOD("unmangleable", return_false);
 
-AST_Symbol.DEFMETHOD("unreferenced", function() {
-    return !this.definition().references.length && !this.scope.pinned();
-});
-
 AST_Symbol.DEFMETHOD("definition", function() {
     return this.thedef;
 });
 
-AST_Symbol.DEFMETHOD("global", function() {
-    return this.definition().global;
-});
-
 function _default_mangler_options(options) {
     options = defaults(options, {
         eval        : false,
@@ -400,6 +485,7 @@ function _default_mangler_options(options) {
         keep_fnames : false,
         reserved    : [],
         toplevel    : false,
+        webkit      : false,
     });
     if (!Array.isArray(options.reserved)) options.reserved = [];
     // Never mangle arguments
@@ -418,7 +504,7 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
     var lname = -1;
 
     if (options.cache && options.cache.props) {
-        var mangled_names = this.mangled_names = Object.create(null);
+        var mangled_names = names_in_use(this, options);
         options.cache.props.each(function(mangled_name) {
             mangled_names[mangled_name] = true;
         });
@@ -433,7 +519,26 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
             lname = save_nesting;
             return true;
         }
-        if (node instanceof AST_Scope) {
+        if (node instanceof AST_BlockScope) {
+            if (options.webkit && node instanceof AST_IterationStatement && node.init instanceof AST_Let) {
+                node.init.definitions.forEach(function(defn) {
+                    defn.name.match_symbol(function(sym) {
+                        if (!(sym instanceof AST_SymbolLet)) return;
+                        var def = sym.definition();
+                        var scope = sym.scope.parent_scope;
+                        var redef = scope.def_variable(sym);
+                        sym.thedef = def;
+                        scope.to_mangle.push(redef);
+                        def.redefined = function() {
+                            return redef;
+                        };
+                    });
+                }, true);
+            }
+            node.to_mangle = [];
+            node.variables.each(function(def) {
+                if (!defer_redef(def)) node.to_mangle.push(def);
+            });
             descend();
             if (options.cache && node instanceof AST_Toplevel) {
                 node.globals.each(mangle);
@@ -443,9 +548,7 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
                 sym.scope = node;
                 sym.reference(options);
             }
-            node.variables.each(function(def) {
-                if (!defer_redef(def)) mangle(def);
-            });
+            node.to_mangle.forEach(mangle);
             return true;
         }
         if (node instanceof AST_Label) {
@@ -456,13 +559,6 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
             node.mangled_name = name;
             return true;
         }
-        if (!options.ie8 && node instanceof AST_Catch) {
-            var def = node.argname.definition();
-            var redef = defer_redef(def, node.argname);
-            descend();
-            if (!redef) mangle(def);
-            return true;
-        }
     });
     this.walk(tw);
     redefined.forEach(mangle);
@@ -472,12 +568,19 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
         def.mangle(options);
     }
 
-    function defer_redef(def, node) {
+    function defer_redef(def) {
+        var sym = def.orig[0];
         var redef = def.redefined();
-        if (!redef) return false;
+        if (!redef) {
+            if (!(sym instanceof AST_SymbolConst)) return false;
+            var scope = def.scope.resolve();
+            if (def.scope === scope) return false;
+            redef = scope.def_variable(sym);
+            scope.to_mangle.push(redef);
+        }
         redefined.push(def);
         def.references.forEach(reference);
-        if (node) reference(node);
+        if (sym instanceof AST_SymbolCatch || sym instanceof AST_SymbolConst) reference(sym);
         return true;
 
         function reference(sym) {
@@ -490,12 +593,11 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
 
 AST_Toplevel.DEFMETHOD("find_colliding_names", function(options) {
     var cache = options.cache && options.cache.props;
-    var avoid = Object.create(null);
+    var avoid = Object.create(RESERVED_WORDS);
     options.reserved.forEach(to_avoid);
     this.globals.each(add_def);
     this.walk(new TreeWalker(function(node) {
-        if (node instanceof AST_Scope) node.variables.each(add_def);
-        if (node instanceof AST_SymbolCatch) add_def(node.definition());
+        if (node instanceof AST_BlockScope) node.variables.each(add_def);
     }));
     return avoid;
 
@@ -519,15 +621,14 @@ AST_Toplevel.DEFMETHOD("expand_names", function(options) {
     var cname = 0;
     this.globals.each(rename);
     this.walk(new TreeWalker(function(node) {
-        if (node instanceof AST_Scope) node.variables.each(rename);
-        if (node instanceof AST_SymbolCatch) rename(node.definition());
+        if (node instanceof AST_BlockScope) node.variables.each(rename);
     }));
 
     function next_name() {
         var name;
         do {
             name = base54(cname++);
-        } while (avoid[name] || RESERVED_WORDS[name]);
+        } while (avoid[name]);
         return name;
     }
 
@@ -538,11 +639,8 @@ AST_Toplevel.DEFMETHOD("expand_names", function(options) {
         var redef = def.redefined();
         var name = redef ? redef.rename || redef.name : next_name();
         def.rename = name;
-        def.orig.forEach(function(sym) {
-            sym.name = name;
-        });
-        def.references.forEach(function(sym) {
-            sym.name = name;
+        def.forEach(function(sym) {
+            if (sym.definition() === def) sym.name = name;
         });
     }
 });
@@ -555,22 +653,24 @@ AST_Sequence.DEFMETHOD("tail_node", function() {
 AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options) {
     options = _default_mangler_options(options);
     base54.reset();
+    var fn = AST_Symbol.prototype.add_source_map;
     try {
-        AST_Node.prototype.print = function(stream, force_parens) {
-            this._print(stream, force_parens);
-            if (this instanceof AST_Symbol && !this.unmangleable(options)) {
-                base54.consider(this.name, -1);
-            } else if (options.properties) {
-                if (this instanceof AST_Dot) {
-                    base54.consider(this.property, -1);
-                } else if (this instanceof AST_Sub) {
-                    skip_string(this.property);
-                }
-            }
+        AST_Symbol.prototype.add_source_map = function() {
+            if (!this.unmangleable(options)) base54.consider(this.name, -1);
         };
+        if (options.properties) {
+            AST_Dot.prototype.add_source_map = function() {
+                base54.consider(this.property, -1);
+            };
+            AST_Sub.prototype.add_source_map = function() {
+                skip_string(this.property);
+            };
+        }
         base54.consider(this.print_to_string(), 1);
     } finally {
-        AST_Node.prototype.print = AST_Node.prototype._print;
+        AST_Symbol.prototype.add_source_map = fn;
+        delete AST_Dot.prototype.add_source_map;
+        delete AST_Sub.prototype.add_source_map;
     }
     base54.sort();
 

lib/sourcemap.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -90,31 +90,30 @@ function create_array_map() {
 }
 
 function SourceMap(options) {
-    options = defaults(options, {
-        content: false,
-        file: null,
-        root: null,
-        orig: null,
-    }, true);
     var sources = create_array_map();
-    var sources_content = options.content && Object.create(null);
+    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 ];
-        map.mappings = map.mappings.split(/;/).map(function(line) {
+        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;
@@ -133,12 +132,15 @@ function SourceMap(options) {
                     if (orig_col >= col) indices = segments[i];
                     if (orig_col <= col) break;
                 }
-                if (!indices || indices.length < 4) return;
+                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) {
@@ -147,7 +149,7 @@ function SourceMap(options) {
         toString: function() {
             return JSON.stringify({
                 version: 3,
-                file: options.file || undefined,
+                file: options.filename || undefined,
                 sourceRoot: options.root || undefined,
                 sources: sources,
                 sourcesContent: sources_content ? sources.map(function(source) {
@@ -160,6 +162,8 @@ function SourceMap(options) {
     };
 
     function add(source, gen_line, gen_col, orig_line, orig_col, name) {
+        if (prev_source == null && source == null) return;
+        prev_source = source;
         if (generated_line < gen_line) {
             generated_column = 0;
             do {
@@ -170,6 +174,7 @@ function SourceMap(options) {
         }
         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;
@@ -177,7 +182,7 @@ function SourceMap(options) {
         original_line = orig_line;
         mappings += vlq_encode(orig_col - original_column);
         original_column = orig_col;
-        if (name != null) {
+        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) ---------------------------------
 
@@ -116,7 +116,7 @@ TreeTransformer.prototype = new TreeWalker;
         if (self.bfinally) self.bfinally = self.bfinally.transform(tw);
     });
     DEF(AST_Catch, function(self, tw) {
-        self.argname = self.argname.transform(tw);
+        if (self.argname) self.argname = self.argname.transform(tw);
         self.body = do_list(self.body, tw);
     });
     DEF(AST_Definitions, function(self, tw) {
@@ -138,6 +138,9 @@ TreeTransformer.prototype = new TreeWalker;
     DEF(AST_Sequence, function(self, tw) {
         self.expressions = do_list(self.expressions, tw);
     });
+    DEF(AST_Await, function(self, tw) {
+        self.expression = self.expression.transform(tw);
+    });
     DEF(AST_Dot, function(self, tw) {
         self.expression = self.expression.transform(tw);
     });
@@ -145,6 +148,9 @@ TreeTransformer.prototype = new TreeWalker;
         self.expression = self.expression.transform(tw);
         self.property = self.property.transform(tw);
     });
+    DEF(AST_Spread, function(self, tw) {
+        self.expression = self.expression.transform(tw);
+    });
     DEF(AST_Unary, function(self, tw) {
         self.expression = self.expression.transform(tw);
     });
@@ -160,10 +166,21 @@ TreeTransformer.prototype = new TreeWalker;
     DEF(AST_Array, function(self, tw) {
         self.elements = do_list(self.elements, tw);
     });
+    DEF(AST_DestructuredArray, function(self, tw) {
+        self.elements = do_list(self.elements, 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);
+    });
     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);
     });
 })(function(node, descend) {

lib/utils.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -87,15 +87,13 @@ DefaultsError.prototype.name = "DefaultsError";
 configure_error_stack(DefaultsError);
 
 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)) {
-        throw new DefaultsError("`" + i + "` is not a supported option", defs);
+    if (croak) for (var i in args) {
+        if (HOP(args, i) && !HOP(defs, i)) throw new DefaultsError("`" + 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];
+    for (var i in args) {
+        if (HOP(args, i)) defs[i] = args[i];
     }
-    return ret;
+    return defs;
 }
 
 function merge(obj, ext) {
@@ -114,48 +112,29 @@ function return_this() { return this; }
 function return_null() { return null; }
 
 var List = (function() {
-    function List(a, f, backwards) {
-        var ret = [], top = [], i;
-        function doit() {
+    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 === skip) continue;
             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);
+                ret.push.apply(ret, val.v);
             } else {
                 ret.push(val);
             }
         }
-            return is_last;
+        return ret;
     }
-        if (Array.isArray(a)) {
-            if (backwards) {
-                for (i = a.length; --i >= 0;) if (doit()) break;
-                ret.reverse();
-                top.reverse();
-            } else {
-                for (i = 0; i < a.length; ++i) if (doit()) break;
-            }
-        } else {
-            for (i in a) if (HOP(a, i)) if (doit()) break;
-        }
-        return top.concat(ret);
-    }
-    List.at_top = function(val) { return new AtTop(val); };
-    List.splice = function(val) { return new Splice(val); };
-    List.last = function(val) { return new Last(val); };
+    List.is_op = function(val) {
+        return val === skip || val instanceof Splice;
+    };
+    List.splice = function(val) {
+        return new Splice(val);
+    };
     var skip = List.skip = {};
-    function AtTop(val) { this.v = val; }
-    function Splice(val) { this.v = val; }
-    function Last(val) { this.v = val; }
+    function Splice(val) {
+        this.v = val;
+    }
     return List;
 })();
 
@@ -164,8 +143,9 @@ function push_uniq(array, 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;
     });
 }
 

package.json

@@ -3,7 +3,7 @@
   "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.9.0",
+  "version": "3.12.2",
   "engines": {
     "node": ">=0.8.0"
   },
@@ -11,7 +11,7 @@
     "Alex Lam <alexlamsl@gmail.com>",
     "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)"
   ],
-  "repository": "mishoo/UglifyJS2",
+  "repository": "mishoo/UglifyJS",
   "main": "tools/node.js",
   "bin": {
     "uglifyjs": "bin/uglifyjs"
@@ -22,9 +22,6 @@
     "tools",
     "LICENSE"
   ],
-  "dependencies": {
-    "commander": "~2.20.3"
-  },
   "devDependencies": {
     "acorn": "~7.1.0",
     "semver": "~6.3.0"

test/benchmark.js

@@ -5,12 +5,11 @@
 
 var createHash = require("crypto").createHash;
 var fetch = require("./fetch");
-var fork = require("child_process").fork;
+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-3.4.1.js",
@@ -70,18 +69,20 @@ urls.forEach(function(url) {
     };
     fetch(url, function(err, res) {
         if (err) throw err;
-        var uglifyjs = fork("bin/uglifyjs", args, { silent: true });
+        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(zlib.createGzip({
             level: zlib.Z_BEST_COMPRESSION
         })).on("data", function(data) {
             results[url].gzip += data.length;
-        }).pipe(createHash("sha1")).on("data", function(data) {
-            results[url].sha1 = data.toString("hex");
+            sha1.update(data);
+        }).on("end", function() {
+            results[url].sha1 = sha1.digest("hex");
             done();
         });
         uglifyjs.stderr.setEncoding("utf8");

test/compress.js

@@ -63,7 +63,6 @@ function make_code(ast, options) {
 
 function parse_test(file) {
     var script = fs.readFileSync(file, "utf8");
-    // TODO try/catch can be removed after fixing https://github.com/mishoo/UglifyJS2/issues/348
     try {
         var ast = U.parse(script, {
             filename: file
@@ -188,6 +187,7 @@ function reminify(orig_options, input_code, input_formatted, stdout) {
             }
         });
         var options_formatted = JSON.stringify(options, null, 4);
+        options.validate = true;
         var result = U.minify(input_code, options);
         if (result.error) {
             log([
@@ -251,6 +251,7 @@ function run_code(code, toplevel) {
 
 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) {
@@ -267,6 +268,7 @@ function test_case(test) {
         quote_style: 3,
     });
     try {
+        input.validate_ast();
         U.parse(input_code);
     } catch (ex) {
         log([
@@ -309,12 +311,11 @@ function test_case(test) {
     if (test.mangle) {
         output.compute_char_frequency(test.mangle);
         output.mangle_names(test.mangle);
-        if (test.mangle.properties) {
-            output = U.mangle_properties(output, test.mangle.properties);
+        if (test.mangle.properties) U.mangle_properties(output, test.mangle.properties);
     }
-    }
-    output = make_code(output, output_options);
-    if (expect != output) {
+    var output_code = make_code(output, output_options);
+    U.AST_Node.log_function();
+    if (expect != output_code) {
         log([
             "!!! failed",
             "---INPUT---",
@@ -327,14 +328,15 @@ function test_case(test) {
             "",
         ].join("\n"), {
             input: input_formatted,
-            output: output,
+            output: output_code,
             expected: expect
         });
         return false;
     }
     // expect == output
     try {
-        U.parse(output);
+        output.validate_ast();
+        U.parse(output_code);
     } catch (ex) {
         log([
             "!!! Test matched expected result but cannot parse output",
@@ -348,7 +350,7 @@ function test_case(test) {
             "",
         ].join("\n"), {
             input: input_formatted,
-            output: output,
+            output: output_code,
             error: ex,
         });
         return false;
@@ -384,7 +386,7 @@ function test_case(test) {
             mangle: test.mangle
         });
         var actual = stdout[toplevel ? 1 : 0];
-        if (test.expect_stdout === true) {
+        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)) {
@@ -407,7 +409,7 @@ function test_case(test) {
             });
             return false;
         }
-        actual = run_code(output, toplevel);
+        actual = run_code(output_code, toplevel);
         if (!sandbox.same_stdout(test.expect_stdout, actual)) {
             log([
                 "!!! failed",

test/compress/arguments.js

@@ -243,20 +243,18 @@ issue_3273: {
         arguments: true,
     }
     input: {
-        function f(a) {
+        (function(a) {
             console.log(arguments[0], a);
             arguments[0]++;
             console.log(arguments[0], a);
-        }
-        f(0);
+        })(0);
     }
     expect: {
-        function f(a) {
+        (function(a) {
             console.log(a, a);
             a++;
             console.log(a, a);
-        }
-        f(0);
+        })(0);
     }
     expect_stdout: [
         "0 0",
@@ -264,26 +262,43 @@ issue_3273: {
     ]
 }
 
+issue_3273_no_call_arg: {
+    options = {
+        arguments: true,
+    }
+    input: {
+        (function(a) {
+            arguments[0] = "FAIL";
+            console.log(a);
+        })();
+    }
+    expect: {
+        (function(a) {
+            arguments[0] = "FAIL";
+            console.log(a);
+        })();
+    }
+    expect_stdout: "undefined"
+}
+
 issue_3273_reduce_vars: {
     options = {
         arguments: true,
         reduce_vars: true,
     }
     input: {
-        function f(a) {
+        (function(a) {
             console.log(arguments[0], a);
             arguments[0]++;
             console.log(arguments[0], a);
-        }
-        f(0);
+        })(0);
     }
     expect: {
-        function f(a) {
+        (function(a) {
             console.log(a, a);
             a++;
             console.log(a, a);
-        }
-        f(0);
+        })(0);
     }
     expect_stdout: [
         "0 0",
@@ -296,22 +311,20 @@ issue_3273_local_strict: {
         arguments: true,
     }
     input: {
-        function f(a) {
+        (function(a) {
             "use strict";
             console.log(arguments[0], a);
             arguments[0]++;
             console.log(arguments[0], a);
-        }
-        f(0);
+        })(0);
     }
     expect: {
-        function f(a) {
+        (function(a) {
             "use strict";
             console.log(arguments[0], a);
             arguments[0]++;
             console.log(arguments[0], a);
-        }
-        f(0);
+        })(0);
     }
     expect_stdout: [
         "0 0",
@@ -325,22 +338,20 @@ issue_3273_local_strict_reduce_vars: {
         reduce_vars: true,
     }
     input: {
-        function f(a) {
+        (function(a) {
             "use strict";
             console.log(arguments[0], a);
             arguments[0]++;
             console.log(arguments[0], a);
-        }
-        f(0);
+        })(0);
     }
     expect: {
-        function f(a) {
+        (function(a) {
             "use strict";
             console.log(arguments[0], a);
             arguments[0]++;
             console.log(arguments[0], a);
-        }
-        f(0);
+        })(0);
     }
     expect_stdout: [
         "0 0",
@@ -354,21 +365,19 @@ issue_3273_global_strict: {
     }
     input: {
         "use strict";
-        function f(a) {
+        (function(a) {
             console.log(arguments[0], a);
             arguments[0]++;
             console.log(arguments[0], a);
-        }
-        f(0);
+        })(0);
     }
     expect: {
         "use strict";
-        function f(a) {
+        (function(a) {
             console.log(arguments[0], a);
             arguments[0]++;
             console.log(arguments[0], a);
-        }
-        f(0);
+        })(0);
     }
     expect_stdout: [
         "0 0",
@@ -383,21 +392,19 @@ issue_3273_global_strict_reduce_vars: {
     }
     input: {
         "use strict";
-        function f(a) {
+        (function(a) {
             console.log(arguments[0], a);
             arguments[0]++;
             console.log(arguments[0], a);
-        }
-        f(0);
+        })(0);
     }
     expect: {
         "use strict";
-        function f(a) {
+        (function(a) {
             console.log(arguments[0], a);
             arguments[0]++;
             console.log(arguments[0], a);
-        }
-        f(0);
+        })(0);
     }
     expect_stdout: [
         "0 0",
@@ -776,3 +783,71 @@ issue_3420_7: {
     }
     expect_stdout: "true"
 }
+
+issue_4200: {
+    options = {
+        arguments: true,
+        keep_fargs: false,
+    }
+    input: {
+        var o = {
+            get p() {
+                return arguments[0];
+            },
+        };
+        console.log(o.p);
+    }
+    expect: {
+        var o = {
+            get p() {
+                return arguments[0];
+            },
+        };
+        console.log(o.p);
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4291_1: {
+    options = {
+        arguments: true,
+        keep_fargs: "strict",
+    }
+    input: {
+        console.log(function() {
+            arguments[0] = "PASS";
+            return arguments;
+        }()[0]);
+    }
+    expect: {
+        console.log(function() {
+            arguments[0] = "PASS";
+            return arguments;
+        }()[0]);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4291_2: {
+    options = {
+        arguments: true,
+        keep_fargs: "strict",
+    }
+    input: {
+        var a = function() {
+            if (arguments[0])
+                arguments[1] = "PASS";
+            return arguments;
+        }(42);
+        console.log(a[1], a[0], a.length);
+    }
+    expect: {
+        var a = function(argument_0) {
+            if (argument_0)
+                arguments[1] = "PASS";
+            return arguments;
+        }(42);
+        console.log(a[1], a[0], a.length);
+    }
+    expect_stdout: "PASS 42 1"
+}

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\\x008\\0"+"\\0\\x01\\x02\\x03\\x04\\x05\\x06\\x07\\b\\t\\n\\v\\f\\r\\x0e\\x0f"+"\\x10\\x11\\x12\\x13\\x14\\x15\\x16\\x17\\x18\\x19\\x1a\\x1b\\x1c\\x1d\\x1e\\x1f"+\' !"# ... }~\\x7f\\x80\\x81 ... \\xfe\\xff\\u0fff\\uffff\'}'
-}
-
-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\\x008\\0"+"\\0\x01\x02\x03\x04\x05\x06\x07\\b\\t\\n\\v\\f\\r\x0e\x0f"+"\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f"+\' !"# ... }~\x7f\x80\x81 ... \xfe\xff\u0fff\uffff\'}'
-}

test/compress/asm.js

@@ -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 };

test/compress/assignments.js

@@ -407,3 +407,57 @@ issue_3429_2: {
     }
     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"
+}

test/compress/async.js

@@ -0,0 +1,498 @@
+await_await: {
+    input: {
+        (async function() {
+            console.log("PASS");
+            await await 42;
+        })();
+    }
+    expect: {
+        (async function() {
+            console.log("PASS");
+            await await 42;
+        })();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+defun_name: {
+    input: {
+        async function await() {
+            console.log("PASS");
+        }
+        await();
+    }
+    expect: {
+        async function await() {
+            console.log("PASS");
+        }
+        await();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+nested_await: {
+    input: {
+        (async function() {
+            console.log(function(await) {
+                return await;
+            }("PASS"));
+        })();
+    }
+    expect: {
+        (async function() {
+            console.log(function(await) {
+                return await;
+            }("PASS"));
+        })();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+reduce_single_use_defun: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        async function f(a) {
+            console.log(a);
+        }
+        f("PASS");
+    }
+    expect: {
+        (async function(a) {
+            console.log(a);
+        })("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+dont_inline: {
+    options = {
+        inline: true,
+    }
+    input: {
+        (async function() {
+            A;
+        })().catch(function() {});
+        console.log("PASS");
+    }
+    expect: {
+        (async function() {
+            A;
+        })().catch(function() {});
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+evaluate: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = async function() {}();
+        console.log(typeof a);
+    }
+    expect: {
+        var a = async function() {}();
+        console.log(typeof a);
+    }
+    expect_stdout: "object"
+    node_version: ">=8"
+}
+
+negate: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        console && async function() {} && console.log("PASS");
+    }
+    expect: {
+        console && async function() {} && console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+negate_iife: {
+    options = {
+        negate_iife: true,
+    }
+    input: {
+        (async function() {
+            console.log("PASS");
+        })();
+    }
+    expect: {
+        !async function() {
+            console.log("PASS");
+        }();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+collapse_vars_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = "FAIL";
+        (async function() {
+            a = "PASS";
+            await 42;
+            return "PASS";
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        (async function() {
+            a = "PASS";
+            await 42;
+            return "PASS";
+        })();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+collapse_vars_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = "FAIL";
+        (async function() {
+            await (a = "PASS");
+            return "PASS";
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        (async function() {
+            await (a = "PASS");
+            return "PASS";
+        })();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+collapse_vars_3: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = "FAIL";
+        (async function() {
+            await (a = "PASS", 42);
+            return "PASS";
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        (async function() {
+            await (a = "PASS", 42);
+            return "PASS";
+        })();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+issue_4335_1: {
+    options = {
+        inline: true,
+    }
+    input: {
+        var await = "PASS";
+        (async function() {
+            console.log(function() {
+                return await;
+            }());
+        })();
+    }
+    expect: {
+        var await = "PASS";
+        (async function() {
+            console.log(function() {
+                return await;
+            }());
+        })();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+issue_4335_2: {
+    options = {
+        inline: true,
+    }
+    input: {
+        (async function() {
+            console.log(function() {
+                function await() {}
+                return "PASS";
+            }());
+        })();
+    }
+    expect: {
+        (async function() {
+            console.log(function() {
+                function await() {}
+                return "PASS";
+            }());
+        })();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+issue_4337: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(a) {
+            a();
+        })(async function() {
+            console.log("PASS");
+        });
+    }
+    expect: {
+        (function(a) {
+            (async function() {
+                console.log("PASS");
+            })();
+        })();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+issue_4340: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        (async function a(a) {
+            console.log(a || "PASS");
+        })();
+    }
+    expect: {
+        (async function a(a) {
+            console.log(a || "PASS");
+        })();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+call_expression: {
+    input: {
+        console.log(typeof async function(log) {
+            (await log)("FAIL");
+        }(console.log).then);
+    }
+    expect_exact: 'console.log(typeof async function(log){(await log)("FAIL")}(console.log).then);'
+    expect_stdout: "function"
+    node_version: ">=8"
+}
+
+property_access_expression: {
+    input: {
+        console.log(typeof async function(con) {
+            (await con).log("FAIL");
+        }(console).then);
+    }
+    expect_exact: 'console.log(typeof async function(con){(await con).log("FAIL")}(console).then);'
+    expect_stdout: "function"
+    node_version: ">=8"
+}
+
+issue_4347_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "foo";
+        f();
+        a = "bar";
+        f();
+        async function f() {
+            console.log(a);
+        }
+    }
+    expect: {
+        var a = "foo";
+        f();
+        a = "bar";
+        f();
+        async function f() {
+            console.log(a);
+        }
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=8"
+}
+
+issue_4347_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        (async function() {
+            throw 42;
+            a = "FAIL";
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        (async function() {
+            throw 42;
+            a = "FAIL";
+        })();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+issue_4349_1: {
+    input: {
+        console.log(typeof async function() {
+            await /abc/;
+        }().then);
+    }
+    expect_exact: "console.log(typeof async function(){await/abc/}().then);"
+    expect_stdout: "function"
+    node_version: ">=8"
+}
+
+issue_4349_2: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(typeof async function() {
+            (function(a) {
+                this[a];
+            }(await 0));
+        }().then);
+    }
+    expect: {
+        console.log(typeof async function() {
+            (function(a) {
+                this[a];
+            }(await 0));
+        }().then);
+    }
+    expect_stdout: "function"
+    node_version: ">=8"
+}
+
+issue_4349_3: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(typeof function(await) {
+            return async function(a) {
+                this[a];
+            }(await);
+        }(this).then);
+    }
+    expect: {
+        console.log(typeof function(await) {
+            return async function(a) {
+                this[a];
+            }(await);
+        }(this).then);
+    }
+    expect_stdout: "function"
+    node_version: ">=8"
+}
+
+issue_4359: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        try {
+            (async function(a) {
+                return a;
+            })(A);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            (async function(a) {
+                return a;
+            })(A);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+issue_4377: {
+    options = {
+        dead_code: true,
+        inline: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(typeof function() {
+            return function() {
+                f;
+                async function f() {}
+                return f();
+            }();
+        }().then);
+    }
+    expect: {
+        console.log(typeof function() {
+            return f();
+            async function f() {}
+        }().then);
+    }
+    expect_stdout: "function"
+    node_version: ">=8"
+}

test/compress/booleans.js

@@ -153,3 +153,31 @@ issue_3690: {
     }
     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/comparisons.js

@@ -93,6 +93,59 @@ self_comparison_2: {
     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,

test/compress/concat-strings.js

@@ -238,6 +238,41 @@ 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,

test/compress/conditionals.js

@@ -55,14 +55,15 @@ ifs_3_should_warn: {
     }
     input: {
         var x, y;
-        if (x && !(x + "1") && y) { // 1
+        // 1
+        if (x && !(x + "1") && y) {
             var qq;
             foo();
         } else {
             bar();
         }
-
-        if (x || !!(x + "1") || y) { // 2
+        // 2
+        if (x || !!(x + "1") || y) {
             foo();
         } else {
             var jj;
@@ -71,9 +72,25 @@ ifs_3_should_warn: {
     }
     expect: {
         var x, y;
-        var qq; bar();          // 1
-        var jj; foo();          // 2
+        // 1
+        var qq; bar();
+        // 2
+        foo(); var jj;
     }
+    expect_warnings: [
+        "WARN: + in boolean context always true [test/compress/conditionals.js:3,18]",
+        "WARN: Boolean && always false [test/compress/conditionals.js:3,12]",
+        "WARN: Condition left of && always false [test/compress/conditionals.js:3,12]",
+        "WARN: Condition always false [test/compress/conditionals.js:3,12]",
+        "WARN: Dropping unreachable code [test/compress/conditionals.js:3,34]",
+        "WARN: + in boolean context always true [test/compress/conditionals.js:10,19]",
+        "WARN: Boolean || always true [test/compress/conditionals.js:10,12]",
+        "WARN: Condition left of || always true [test/compress/conditionals.js:10,12]",
+        "WARN: Condition always true [test/compress/conditionals.js:10,12]",
+        "WARN: Dropping unreachable code [test/compress/conditionals.js:12,15]",
+        "WARN: Dropping side-effect-free statement [test/compress/conditionals.js:3,12]",
+        "WARN: Dropping side-effect-free statement [test/compress/conditionals.js:10,12]",
+    ]
 }
 
 ifs_4: {
@@ -783,6 +800,28 @@ cond_12: {
     }
 }
 
+cond_13: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        x ? y(a) : z(a);
+        x ? y.f(a) : z.f(a);
+        x ? y.f(a) : z.g(a);
+        x ? y.f()(a) : z.g()(a);
+        x ? y.f.u(a) : z.g.u(a);
+        x ? y.f().u(a) : z.g().u(a);
+    }
+    expect: {
+        (x ? y : z)(a);
+        (x ? y : z).f(a);
+        x ? y.f(a) : z.g(a);
+        (x ? y.f() : z.g())(a);
+        (x ? y.f : z.g).u(a);
+        (x ? y.f() : z.g()).u(a);
+    }
+}
+
 ternary_boolean_consequent: {
     options = {
         booleans: true,
@@ -1137,7 +1176,7 @@ issue_1645_2: {
     expect_stdout: true
 }
 
-condition_symbol_matches_consequent: {
+condition_matches_consequent: {
     options = {
         conditionals: true,
     }
@@ -1166,6 +1205,35 @@ condition_symbol_matches_consequent: {
     expect_stdout: "3 7 true 4"
 }
 
+condition_matches_alternative: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        function foo(x, y) {
+            return x.p ? y[0] : x.p;
+        }
+        function bar() {
+            return g ? h : g;
+        }
+        var g = 4;
+        var h = 5;
+        console.log(foo({ p: 3 }, [ null ]), foo({ p: 0 }, [ 7 ]), foo({ p: true } , [ false ]), bar());
+    }
+    expect: {
+        function foo(x, y) {
+            return x.p && y[0];
+        }
+        function bar() {
+            return g && h;
+        }
+        var g = 4;
+        var h = 5;
+        console.log(foo({ p: 3 }, [ null ]), foo({ p: 0 }, [ 7 ]), foo({ p: true } , [ false ]), bar());
+    }
+    expect_stdout: "null 0 false 5"
+}
+
 delete_conditional_1: {
     options = {
         booleans: true,
@@ -1384,7 +1452,7 @@ hoist_decl: {
     }
     expect: {
         var a, b;
-        x() ? y() : z();
+        (x() ? y : z)();
     }
 }
 
@@ -1666,3 +1734,130 @@ issue_3668: {
     }
     expect_stdout: "undefined"
 }
+
+conditional_assignments_1: {
+    options = {
+        conditionals: true,
+        sequences: true,
+    }
+    input: {
+        function f(a, b, c, d) {
+            a = b;
+            if (c) a = d;
+            return a;
+        }
+        function g(a, b, c, d) {
+            a = b;
+            if (c); else a = d;
+            return a;
+        }
+        console.log(f(0, "FAIL", 1, "PASS"), g(0, "PASS", 1, "FAIL"));
+    }
+    expect: {
+        function f(a, b, c, d) {
+            return a = c ? d : b, a;
+        }
+        function g(a, b, c, d) {
+            return a = c ? b : d, a;
+        }
+        console.log(f(0, "FAIL", 1, "PASS"), g(0, "PASS", 1, "FAIL"));
+    }
+    expect_stdout: "PASS PASS"
+}
+
+conditional_assignments_2: {
+    options = {
+        conditionals: true,
+        sequences: true,
+    }
+    input: {
+        function f1(b, c, d) {
+            a = b;
+            if (c) a = d;
+            return a;
+        }
+        function f2(a, c, d) {
+            a = b;
+            if (c) a = d;
+            return a;
+        }
+        function f3(a, b, d) {
+            a = b;
+            if (c) a = d;
+            return a;
+        }
+        function f4(a, b, c) {
+            a = b;
+            if (c) a = d;
+            return a;
+        }
+    }
+    expect: {
+        function f1(b, c, d) {
+            return a = c ? d : b, a;
+        }
+        function f2(a, c, d) {
+            return a = b, c && (a = d), a;
+        }
+        function f3(a, b, d) {
+            return a = b, c && (a = d), a;
+        }
+        function f4(a, b, c) {
+            return a = b, c && (a = d), a;
+        }
+    }
+}
+
+conditional_assignments_3: {
+    options = {
+        conditionals: true,
+        sequences: true,
+    }
+    input: {
+        console.log(function(a, b) {
+            a = "PASS";
+            if (b) a = a;
+            return a;
+        }(0, 1));
+    }
+    expect: {
+        console.log(function(a, b) {
+            return a = "PASS", b && (a = a), a;
+        }(0, 1));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3808_1: {
+    options = {
+        conditionals: true,
+        side_effects: true,
+    }
+    input: {
+        var a;
+        a = "PASS", [] + "" && (a = "FAIL");
+        console.log(a);
+    }
+    expect: {
+        var a;
+        a = [] + "" ? "FAIL" : "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3808_2: {
+    options = {
+        conditionals: true,
+        side_effects: true,
+    }
+    input: {
+        var a;
+        console.log((a = "PASS", [] + "" && (a = "FAIL")), a);
+    }
+    expect: {
+        var a;
+        console.log((a = "PASS", [] + "" && (a = "FAIL")), a);
+    }
+    expect_stdout: " PASS"
+}

test/compress/dead-code.js

@@ -59,6 +59,9 @@ dead_code_2_should_warn: {
         f();
     }
     expect_stdout: true
+    expect_warnings: [
+        "WARN: Dropping unreachable code [test/compress/dead-code.js:8,12]",
+    ]
     node_version: "<=4"
 }
 
@@ -89,14 +92,84 @@ dead_code_constant_boolean_should_warn_more: {
         function bar() {}
         // nothing for the while
         // as for the for, it should keep:
-        var moo;
         var x = 10, y;
+        var moo;
         bar();
     }
     expect_stdout: true
+    expect_warnings: [
+        "WARN: + in boolean context always true [test/compress/dead-code.js:1,33]",
+        "WARN: Boolean || always true [test/compress/dead-code.js:1,16]",
+        "WARN: Dropping unreachable code [test/compress/dead-code.js:1,45]",
+        "WARN: Boolean expression always true [test/compress/dead-code.js:6,47]",
+        "WARN: Boolean && always false [test/compress/dead-code.js:6,28]",
+        "WARN: Dropping unreachable code [test/compress/dead-code.js:6,63]",
+        "WARN: Dropping side-effect-free statement [test/compress/dead-code.js:1,15]",
+        "WARN: Dropping side-effect-free statement [test/compress/dead-code.js:6,28]",
+    ]
     node_version: "<=4"
 }
 
+trim_try: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        try {
+            var a;
+        } catch (e) {
+            console.log("FAIL");
+        } finally {
+            console.log(a);
+        }
+    }
+    expect: {
+        var a;
+        console.log(a);
+    }
+    expect_stdout: "undefined"
+}
+
+trim_finally_1: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        try {
+            console.log("PASS");
+        } finally {
+            var a;
+        }
+    }
+    expect: {
+        console.log("PASS");
+        var a;
+    }
+    expect_stdout: "PASS"
+}
+
+trim_finally_2: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        try {
+            console.log("PASS");
+        } catch (e) {
+        } finally {
+            var a;
+        }
+    }
+    expect: {
+        try {
+            console.log("PASS");
+            var a;
+        } catch (e) {
+        }
+    }
+    expect_stdout: "PASS"
+}
+
 try_catch_finally: {
     options = {
         conditionals: true,
@@ -130,10 +203,7 @@ try_catch_finally: {
             a = 3;
             console.log("PASS");
         }();
-        try {
         console.log(a);
-        } finally {
-        }
     }
     expect_stdout: [
         "PASS",
@@ -179,7 +249,7 @@ collapse_vars_lvalues_drop_assign: {
     }
 }
 
-collapse_vars_misc1: {
+collapse_vars_misc: {
     options = {
         collapse_vars: true,
         dead_code: true,
@@ -892,3 +962,440 @@ issue_3578: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3830_1: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        var o = {
+            set p(v) {
+                o = o.p = o = v;
+            }
+        };
+        o.p = "PASS";
+        console.log(o);
+    }
+    expect: {
+        var o = {
+            set p(v) {
+                o = o.p = o = v;
+            }
+        };
+        o.p = "PASS";
+        console.log(o);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3830_2: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = o[a] = a = v;
+            }
+        };
+        o[a] = "PASS";
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = o[a] = a = v;
+            }
+        };
+        o[a] = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3830_3: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        function f() {
+            return a;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = o[f()] = a = v;
+            }
+        };
+        o[f()] = "PASS";
+        console.log(a);
+    }
+    expect: {
+        function f() {
+            return a;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = o[f()] = a = v;
+            }
+        };
+        o[f()] = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3830_4: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        function f() {
+            return o;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = f()[a] = a = v;
+            }
+        };
+        f()[a] = "PASS";
+        console.log(a);
+    }
+    expect: {
+        function f() {
+            return o;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = f()[a] = a = v;
+            }
+        };
+        f()[a] = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3830_5: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        function f() {
+            return o;
+        }
+        function g() {
+            return a;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = f()[g()] = a = v;
+            }
+        };
+        f()[g()] = "PASS";
+        console.log(a);
+    }
+    expect: {
+        function f() {
+            return o;
+        }
+        function g() {
+            return a;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = f()[g()] = a = v;
+            }
+        };
+        f()[g()] = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3830_6: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        function f() {
+            return o;
+        }
+        function g() {
+            return a;
+        }
+        function h(v) {
+            a = f()[g()] = a = v;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                h(v);
+            }
+        };
+        o.FAIL = "PASS";
+        console.log(a);
+    }
+    expect: {
+        function f() {
+            return o;
+        }
+        function g() {
+            return a;
+        }
+        function h(v) {
+            a = f()[g()] = a = v;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                h(v);
+            }
+        };
+        o.FAIL = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+redundant_assignments: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        var a = a = "PASS", b = "FAIL";
+        b = b = "PASS";
+        console.log(a, b);
+    }
+    expect: {
+        var a = "PASS", b = "FAIL";
+        b = "PASS";
+        console.log(a, b);
+    }
+    expect_stdout: "PASS PASS"
+}
+
+self_assignments_1: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        var a = "PASS";
+        a = a;
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        a;
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+self_assignments_2: {
+    options = {
+        dead_code: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "q", o = {
+            p: "PASS",
+        };
+        o.p = o.p;
+        o[a] = o[a];
+        console.log(o.p, o[a]);
+    }
+    expect: {
+        var a = "q", o = {
+            p: "PASS",
+        };
+        console.log(o.p, o[a]);
+    }
+    expect_stdout: "PASS undefined"
+}
+
+self_assignments_3: {
+    options = {
+        dead_code: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "q", o = {
+            p: "FAIL",
+            get q() {
+                return "PASS";
+            },
+            set q(v) {
+                this.p = v;
+            },
+        };
+        o.p = o.p;
+        o[a] = o[a];
+        console.log(o.p, o[a]);
+    }
+    expect: {
+        var a = "q", o = {
+            p: "FAIL",
+            get q() {
+                return "PASS";
+            },
+            set q(v) {
+                this.p = v;
+            },
+        };
+        o.p = o.p;
+        o[a] = o[a];
+        console.log(o.p, o[a]);
+    }
+    expect_stdout: "PASS PASS"
+}
+
+self_assignments_4: {
+    options = {
+        dead_code: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var i = 0, l = [ "PASS" ];
+        l[0] = l[0];
+        l[i] = l[i];
+        console.log(l[0], i);
+    }
+    expect: {
+        var i = 0, l = [ "PASS" ];
+        console.log(l[0], i);
+    }
+    expect_stdout: "PASS 0"
+}
+
+self_assignments_5: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        passes: 3,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var i = 0, l = [ "FAIL", "PASS" ];
+        l[0] = l[0];
+        l[i] = l[i];
+        l[i++] = l[i++];
+        console.log(l[0], i);
+    }
+    expect: {
+        var i = 0, l = [ "FAIL", "PASS" ];
+        l[0];
+        l[0];
+        l[0] = l[1];
+        console.log(l[0], 2);
+    }
+    expect_stdout: "PASS 2"
+}
+
+self_assignments_6: {
+    options = {
+        dead_code: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var o = {
+            p: "PASS",
+        };
+        console.log(o.p = o.p);
+    }
+    expect: {
+        var o = {
+            p: "PASS",
+        };
+        console.log(o.p);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3967: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            a = 0 in (a = "PASS");
+        } catch (e) {}
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        try {
+            a = 0 in (a = "PASS");
+        } catch (e) {}
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4051: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        try {
+            delete (A = A);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            delete (A = A);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4366: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        function f() {
+            return "PASS";
+            ({
+                p: 42,
+                get p() {},
+            });
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            return "PASS";
+        }
+        console.log(f());
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}

test/compress/directives.js

@@ -46,7 +46,7 @@ simple_statement_is_not_a_directive: {
 drop_lone_use_strict: {
     options = {
         directives: true,
-        side_effects: true,
+        unused: true,
     }
     input: {
         function f1() {
@@ -66,10 +66,8 @@ drop_lone_use_strict: {
         function f1() {
         }
         function f2() {
-            "use strict";
-            function f3() {
-            }
         }
+        (function() {})();
     }
 }
 

test/compress/drop-unused.js

@@ -1730,7 +1730,7 @@ chained_3: {
     expect: {
         console.log(function(a, b) {
             var c = b;
-            b++;
+            +b;
             return c;
         }(0, 2));
     }
@@ -1997,7 +1997,7 @@ issue_3146_4: {
     expect_stdout: "PASS"
 }
 
-issue_3192: {
+issue_3192_1: {
     options = {
         unused: true,
     }
@@ -2025,6 +2025,26 @@ issue_3192: {
     ]
 }
 
+issue_3192_2: {
+    options = {
+        keep_fargs: "strict",
+        unused: true,
+    }
+    input: {
+        "use strict";
+        (function(a) {
+            console.log(a = "foo", arguments[0]);
+        })("bar");
+    }
+    expect: {
+        "use strict";
+        (function() {
+            console.log("foo", arguments[0]);
+        })("bar");
+    }
+    expect_stdout: "foo bar"
+}
+
 issue_3233: {
     options = {
         pure_getters: "strict",
@@ -2161,8 +2181,7 @@ issue_3515_1: {
     expect: {
         var c = 0;
         (function() {
-            this[c++] = 0;
-            for (var key20 in !0);
+            for (var key20 in !(this[c++] = 0));
         })();
         console.log(c);
     }
@@ -2285,7 +2304,7 @@ issue_3598: {
         try {
             (function() {
                 a = "PASS";
-                var c = (void (c.p = 0))[!1];
+                (void ((void 0).p = 0))[!1];
             })();
         } catch (e) {}
         console.log(a);
@@ -2366,7 +2385,7 @@ function_parameter_ie8: {
     }
     expect: {
         (function() {
-            (function f() {
+            (function() {
                 console.log("PASS");
             })();
         })();
@@ -2444,3 +2463,652 @@ issue_3746: {
     }
     expect_stdout: "PASS"
 }
+
+drop_duplicated_side_effects: {
+    options = {
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        for (var i = 1; i--;)
+            var a = 0, b = ++a;
+        console.log(a);
+    }
+    expect: {
+        var a = 0;
+        for (var i = 1; i--;)
+            a = 0, ++a;
+        console.log(a);
+    }
+    expect_stdout: "1"
+}
+
+drop_duplicated_var_catch: {
+    options = {
+        unused: true,
+    }
+    input: {
+        function f() {
+            try {
+                x();
+            } catch (a) {
+                var a, a;
+            }
+        }
+    }
+    expect: {
+        function f() {
+            try {
+                x();
+            } catch (a) {
+                var a;
+            }
+        }
+    }
+}
+
+issue_3802_1: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        a += 0;
+        var a = function() {};
+        console.log(typeof a);
+    }
+    expect: {
+        var a = 0;
+        a += 0;
+        a = function() {};
+        console.log(typeof a);
+    }
+    expect_stdout: "function"
+}
+
+issue_3802_2: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        a += 0;
+        var a = function() {};
+        console.log(typeof a);
+    }
+    expect: {
+        0;
+        var a = function() {};
+        console.log(typeof a);
+    }
+    expect_stdout: "function"
+}
+
+issue_3899: {
+    options = {
+        assignments: true,
+        evaluate: true,
+        functions: true,
+        inline: true,
+        join_vars: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        a = a + 1;
+        var a = function f(b) {
+            return function() {
+                return b;
+            };
+        }(2);
+        console.log(typeof a);
+    }
+    expect: {
+        function a() {
+            return 2;
+        }
+        console.log(typeof a);
+    }
+    expect_stdout: "function"
+}
+
+cross_scope_assign_chain: {
+    options = {
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a, b = 0;
+        (function() {
+            a = b;
+            a++;
+            while (b++);
+        })();
+        console.log(a ? "PASS" : "FAIL");
+    }
+    expect: {
+        var a, b = 0;
+        (function() {
+            a = b;
+            a++;
+            while (b++);
+        })();
+        console.log(a ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+assign_if_assign_read: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(a) {
+            var b;
+            do {
+                b = "FAIL";
+                if (Array.isArray(a)) {
+                    b = a[0];
+                    console.log(b);
+                }
+            } while (!console);
+        })([ "PASS" ]);
+    }
+    expect: {
+        (function(a) {
+            var b;
+            do {
+                "FAIL";
+                if (Array.isArray(a)) {
+                    b = a[0];
+                    console.log(b);
+                }
+            } while (!console);
+        })([ "PASS" ]);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3951: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = console.log("PASS");
+        console.log(a);
+        a = "0";
+        console.log(a.p = 0);
+        a && a;
+    }
+    expect: {
+        var a = console.log("PASS");
+        console.log(a);
+        a = "0";
+        console.log(a.p = 0);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+        "0",
+    ]
+}
+
+issue_3956: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        (function(a) {
+            function f(b) {
+                console.log(b);
+                a = 1;
+            }
+            var c = f(c += 0);
+            (function(d) {
+                console.log(d);
+            })(console.log(a) ^ 1, c);
+        })();
+    }
+    expect: {
+        var c, d;
+        c += 0,
+        console.log(NaN),
+        d = 1 ^ console.log(1),
+        console.log(d);
+    }
+    expect_stdout: [
+        "NaN",
+        "1",
+        "1",
+    ]
+}
+
+issue_3962_1: {
+    options = {
+        evaluate: true,
+        keep_fargs: "strict",
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        function f(b, c) {
+            do {
+                var d = console + e, e = 0..toString() === b;
+            } while (0);
+            if (c) console.log("PASS");
+        }
+        var a = f(a--, 1);
+        a;
+    }
+    expect: {
+        var a = 0;
+        a = (function(c) {
+            do {
+                console;
+                0..toString();
+            } while (0);
+            if (c) console.log("PASS");
+        }(1), 0);
+        void 0;
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3962_2: {
+    options = {
+        keep_fargs: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        function f(b, c) {
+            do {
+                var d = console + e, e = 0..toString() === b;
+            } while (0);
+            if (c) console.log("PASS");
+        }
+        var a = f(a--, 1);
+        a;
+    }
+    expect: {
+        var a = 0;
+        a = (function(c) {
+            do {
+                console;
+                0..toString();
+            } while (0);
+            if (c) console.log("PASS");
+        }(1), 0);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3986: {
+    options = {
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0, b = 0;
+        (function() {
+            try {
+                throw 42;
+            } catch (e) {
+                a++;
+            }
+            b = b && 0;
+        })(b *= a);
+        console.log(b);
+    }
+    expect: {
+        var a = 0, b = 0;
+        (function() {
+            try {
+                throw 42;
+            } catch (e) {
+                a++;
+            }
+            b = b && 0;
+        })(b *= a);
+        console.log(b);
+    }
+    expect_stdout: "0"
+}
+
+issue_4017: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        console.log(function f() {
+            var b = c &= 0;
+            var c = a++ + (A = a);
+            var d = c && c[f];
+        }());
+    }
+    expect: {
+        var a = 0;
+        console.log(function() {
+            c &= 0;
+            var c = (a++, A = a, 0);
+        }());
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4025: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0, b = 0, c = 0, d = a++;
+        try {
+            var e = console.log(c), f = b;
+        } finally {
+            var d = b = 1, d = c + 1;
+            c = 0;
+        }
+        console.log(a, b, d);
+    }
+    expect: {
+        var c = 0;
+        try {
+            console.log(c);
+        } finally {
+            var d = c + 1;
+            c = 0;
+        }
+        console.log(1, 1, d);
+    }
+    expect_stdout: [
+        "0",
+        "1 1 1",
+    ]
+}
+
+forin_var_1: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var k;
+        for (k in [ 1, 2 ])
+            console.log(k);
+        for (k in { PASS: 3 })
+            console.log(k);
+        console.log(k);
+    }
+    expect: {
+        for (var k in [ 1, 2 ])
+            console.log(k);
+        for (k in { PASS: 3 })
+            console.log(k);
+        console.log(k);
+    }
+    expect_stdout: [
+        "0",
+        "1",
+        "PASS",
+        "PASS",
+    ]
+}
+
+forin_var_2: {
+    options = {
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            switch (0) {
+              case function() {
+                    for (a in 0);
+                }:
+                var b = 0;
+            }
+            for (var c = 0; a;);
+            var a;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            switch (0) {
+              case function() {
+                    for (a in 0);
+                }:
+            }
+            for (; a;);
+            var a;
+        }());
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4133: {
+    options = {
+        evaluate: true,
+        merge_vars: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        var b = [ a-- ], c = b && b[c];
+        console.log(a);
+    }
+    expect: {
+        var b = 1;
+        console.log(0);
+    }
+    expect_stdout: "0"
+}
+
+issue_4144: {
+    options = {
+        keep_fargs: "strict",
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(a, b) {
+            var b = console, c = ++b;
+        })(console.log("PASS"), 0);
+    }
+    expect: {
+        (function(b) {
+            b = console,
+            ++b;
+        })(console.log("PASS"));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4146: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f(a, b) {
+            function g() {}
+            var a = g;
+            var c = b;
+            c.p;
+            console.log(typeof a);
+        }
+        f("FAIL", 42);
+    }
+    expect: {
+        (function(a, b) {
+            a = function () {};
+            var c = b;
+            c.p;
+            console.log(typeof a);
+        })(0, 42);
+    }
+    expect_stdout: "function"
+}
+
+var_catch_redefined: {
+    options = {
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            throw "PASS";
+        } catch (a) {
+            function f() {
+                return a;
+            }
+            console.log(a);
+        }
+        f();
+    }
+    expect: {
+        var a = "FAIL";
+        try {
+            throw "PASS";
+        } catch (a) {
+            function f() {
+                return a;
+            }
+            console.log(a);
+        }
+        f();
+    }
+    expect_stdout: "PASS"
+}
+
+single_use_catch_redefined: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        try {
+            throw 2;
+        } catch (a) {
+            function g() {
+                return a;
+            }
+        }
+        console.log(g());
+    }
+    expect: {
+        var a = 1;
+        try {
+            throw 2;
+        } catch (a) {
+            function g() {
+                return a;
+            }
+        }
+        console.log(g());
+    }
+    expect_stdout: true
+}
+
+issue_4184: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var a = function() {}, b = [ a, 1 && b, a = {} ];
+            try {
+                throw 42;
+            } catch (a) {
+                {
+                    console.log(a);
+                }
+            }
+        })();
+    }
+    expect: {
+        (function() {
+            var b = [ function() {}, 1 && b, {} ];
+            try {
+                throw 42;
+            } catch (a) {
+                console.log(a);
+            }
+        })();
+    }
+    expect_stdout: "42"
+}
+
+issue_4235: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        (function() {
+            {
+                const f = 0;
+            }
+            (function f() {
+                var f = console.log(f);
+            })();
+        })();
+    }
+    expect: {
+        (function() {
+            f = console.log(f),
+            void 0;
+            var f;
+        })();
+    }
+    expect_stdout: "undefined"
+}

test/compress/evaluate.js

@@ -558,34 +558,51 @@ unsafe_array: {
         unsafe: true,
     }
     input: {
-        console.log(
-            [1, , 3][1],
-            [1, 2, 3, a] + 1,
-            [1, 2, 3, 4] + 1,
-            [1, 2, 3, a][0] + 1,
-            [1, 2, 3, 4][0] + 1,
-            [1, 2, 3, 4][6 - 5] + 1,
-            [1, , 3, 4][6 - 5] + 1,
-            [[1, 2], [3, 4]][0] + 1,
-            [[1, 2], [3, 4]][6 - 5][1] + 1,
-            [[1, 2], , [3, 4]][6 - 5][1] + 1
-        );
+        var a = "PASS";
+        Array.prototype[1] = a;
+        console.log([, ].length);
+        console.log("" + [, , ]);
+        console.log([1, , 3][1]);
+        console.log([1, 2, 3, a] + 1);
+        console.log([1, 2, 3, 4] + 1);
+        console.log([1, 2, 3, a][0] + 1);
+        console.log([1, 2, 3, 4][0] + 1);
+        console.log([1, 2, 3, 4][6 - 5] + 1);
+        console.log([1, , 3, 4][6 - 5] + 1);
+        console.log([[1, 2], [3, 4]][0] + 1);
+        console.log([[1, 2], [3, 4]][6 - 5][1] + 1);
+        console.log([[1, 2], , [3, 4]][6 - 5][1] + 1);
     }
     expect: {
-        console.log(
-            void 0,
-            [1, 2, 3, a] + 1,
-            "1,2,3,41",
-            [1, 2, 3, a][0] + 1,
-            2,
-            3,
-            NaN,
-            "1,21",
-            5,
-            (void 0)[1] + 1
-        );
+        var a = "PASS";
+        Array.prototype[1] = a;
+        console.log([, ].length);
+        console.log("" + [, , ]);
+        console.log([1, , 3][1]);
+        console.log([1, 2, 3, a] + 1);
+        console.log("1,2,3,41");
+        console.log([1, 2, 3, a][0] + 1);
+        console.log(2);
+        console.log(3);
+        console.log([1, , 3, 4][1] + 1);
+        console.log("1,21");
+        console.log(5);
+        console.log([[1, 2], , [3, 4]][1][1] + 1);
     }
-    expect_stdout: true
+    expect_stdout: [
+        "1",
+        ",PASS",
+        "PASS",
+        "1,2,3,PASS1",
+        "1,2,3,41",
+        "2",
+        "2",
+        "3",
+        "PASS1",
+        "1,21",
+        "5",
+        "A1",
+    ]
 }
 
 unsafe_string: {
@@ -1579,9 +1596,9 @@ issue_2968_1: {
     expect: {
         var c = "FAIL";
         (function() {
-            b = -(a = 42),
-            void ((a <<= 0) && (a[(c = "PASS", 0 >>> (b += 1))] = 0));
-            var a, b;
+            a = 42,
+            void ((a <<= 0) && (a[(c = "PASS", 0)] = 0));
+            var a;
         })();
         console.log(c);
     }
@@ -2190,3 +2207,870 @@ issue_3755: {
     }
     expect_stdout: "undefined"
 }
+
+void_side_effects: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = void console.log("PASS");
+        console.log(a);
+    }
+    expect: {
+        console.log("PASS");
+        console.log(void 0);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+    ]
+}
+
+no_returns: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = function() {
+            console.log("PASS");
+        }();
+        console.log(a);
+    }
+    expect: {
+        (function() {
+            console.log("PASS");
+        })();
+        console.log(void 0);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+    ]
+}
+
+void_returns: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = function f() {
+            function g(b) {
+                if (b) console.log("FAIL");
+            }
+            while (1) {
+                console.log("PASS");
+                try {
+                    if (console) return;
+                } catch (e) {
+                    return g(e);
+                }
+            }
+        }();
+        console.log(a);
+    }
+    expect: {
+        (function() {
+            function g(b) {
+                if (b) console.log("FAIL");
+            }
+            while (1) {
+                console.log("PASS");
+                try {
+                    if (console) return;
+                } catch (e) {
+                    return g(e);
+                }
+            }
+        })();
+        console.log(void 0);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+    ]
+}
+
+void_returns_recursive: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = function f() {
+            function g(b) {
+                return f();
+            }
+            while (1) {
+                console.log("PASS");
+                try {
+                    if (console) return;
+                } catch (e) {
+                    return g(e);
+                }
+            }
+        }();
+        console.log(a);
+    }
+    expect: {
+        var a = function f() {
+            function g(b) {
+                return f();
+            }
+            while (1) {
+                console.log("PASS");
+                try {
+                    if (console) return;
+                } catch (e) {
+                    return g();
+                }
+            }
+        }();
+        console.log(a);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+    ]
+}
+
+issue_3878_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var b = function(a) {
+            return (a = 0) == (a && this > (a += 0));
+        }();
+        console.log(b ? "PASS" : "FAIL");
+    }
+    expect: {
+        console.log(true ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3878_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "foo";
+        a++ + a;
+        a && a;
+        console.log(a);
+    }
+    expect: {
+        var a = "foo";
+        a++ + a;
+        a;
+        console.log(a);
+    }
+    expect_stdout: "NaN"
+}
+
+issue_3882: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            return console.log(a++), a && this;
+        }
+        var b = f();
+        console.log(b);
+    }
+    expect: {
+        var b = function(a) {
+            return console.log(a++), a && this;
+        }();
+        console.log(b);
+    }
+    expect_stdout: [
+        "NaN",
+        "NaN",
+    ]
+}
+
+issue_3887: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(b) {
+            try {
+                b-- && console.log("PASS");
+            } catch (a_2) {}
+        })(1);
+    }
+    expect: {
+        (function(b) {
+            try {
+                1, console.log("PASS");
+            } catch (a_2) {}
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3903: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        function f(b, c) {
+            return console, c;
+        }
+        var d = f(f(), a = a);
+        console.log(d);
+    }
+    expect: {
+        function f(b, c) {
+            return console, c;
+        }
+        f(f(), "PASS");
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3905: {
+    options = {
+        evaluate: true,
+        passes: 2,
+        unused: true,
+    }
+    input: {
+        (function(a, a) {
+            return console.log(a = 0), a && console.log("FAIL");
+        })("foo", 42);
+    }
+    expect: {
+        (function(a, a) {
+            return console.log(a = 0), a && console.log("FAIL");
+        })("foo", 42);
+    }
+    expect_stdout: "0"
+}
+
+issue_3920: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = function(b) {
+            return (b[b = 0] = 0) >= (b ? 0 : 1);
+        }("foo");
+        console.log(a);
+    }
+    expect: {
+        (function(b) {
+            "foo"[0] = 0;
+        })();
+        console.log(false);
+    }
+    expect_stdout: "false"
+}
+
+inlined_increment_prefix: {
+    options = {
+        evaluate: true,
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 0;
+        (function() {
+            ++a;
+        })();
+        console.log(a += 0);
+    }
+    expect: {
+        var a = 0;
+        void ++a;
+        console.log(1);
+    }
+    expect_stdout: "1"
+}
+
+inlined_increment_postfix: {
+    options = {
+        evaluate: true,
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 0;
+        (function() {
+            a++;
+        })();
+        console.log(a += 0);
+    }
+    expect: {
+        var a = 0;
+        void a++;
+        console.log(1);
+    }
+    expect_stdout: "1"
+}
+
+compound_assignment_to_property: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        1 + (0..p >>= 0) && console.log("PASS");
+    }
+    expect: {
+        1 + (0..p >>= 0),
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_2208_assign: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        a = 42;
+        console.log({
+            p: function() {
+                return function() {
+                    return this.a;
+                }();
+            }
+        }.p());
+    }
+    expect: {
+        a = 42;
+        console.log({
+            p: function() {
+                return function() {
+                    return this.a;
+                }();
+            }
+        }.p());
+    }
+    expect_stdout: "42"
+}
+
+issue_2208_postfix: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        a = 41;
+        a++;
+        console.log({
+            p: function() {
+                return function() {
+                    return this.a;
+                }();
+            }
+        }.p());
+    }
+    expect: {
+        a = 41;
+        a++;
+        console.log({
+            p: function() {
+                return function() {
+                    return this.a;
+                }();
+            }
+        }.p());
+    }
+    expect_stdout: "42"
+}
+
+issue_2208_prefix: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        a = 43;
+        --a;
+        console.log({
+            p: function() {
+                return function() {
+                    return this.a;
+                }();
+            }
+        }.p());
+    }
+    expect: {
+        a = 43;
+        --a;
+        console.log({
+            p: function() {
+                return function() {
+                    return this.a;
+                }();
+            }
+        }.p());
+    }
+    expect_stdout: "42"
+}
+
+issue_3933: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(a, b) {
+            a && (b ^= 1) && console.log("PASS");
+        })(1);
+    }
+    expect: {
+        (function(a, b) {
+            1, 1, console.log("PASS");
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3935: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log(function f(a) {
+            return a++;
+        }());
+    }
+    expect: {
+        console.log(NaN);
+    }
+    expect_stdout: "NaN"
+}
+
+issue_3937: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var a = 123;
+        (a++ + (b = a))[b] ? 0 ? a : b : 0 ? a : b;
+        console.log(a, b);
+    }
+    expect: {
+        var a = 123;
+        (a++ + (b = a))[b], 0, b;
+        console.log(a, b);
+    }
+    expect_stdout: "124 124"
+}
+
+issue_3944: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            function f() {
+                while (function() {
+                    var a = 0 == (b && b.p), b = console.log(a);
+                }());
+                f;
+            }
+            f();
+        })();
+    }
+    expect: {
+        void function f() {
+            while (a = 0 == (a = void 0), console.log(a), void 0);
+            var a;
+            f;
+        }();
+    }
+    expect_stdout: "false"
+}
+
+issue_3953: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        function f(a) {
+            (a += 0 * (a = 0)) && console.log("PASS");
+        }
+        f(1);
+    }
+    expect: {
+        function f(a) {
+            (a += 0 * (a = 0)) && console.log("PASS");
+        }
+        f(1);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3988: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        function f(b) {
+            return ("" + (b &= 0))[b && this];
+        }
+        var a = f();
+        console.log(a);
+    }
+    expect: {
+        var a = function(b) {
+            return ("" + (b &= 0))[b && this];
+        }();
+        console.log(a);
+    }
+    expect_stdout: "0"
+}
+
+operator_in: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        Object.prototype.PASS = 0;
+        console.log(0 in [ 1 ]);
+        console.log(0 in [ , ]);
+        console.log(0 / 0 in { NaN: 2 });
+        console.log("PASS" in { });
+        console.log("FAIL" in { });
+        console.log("toString" in { });
+        console.log("toString" in { toString: 3 });
+    }
+    expect: {
+        Object.prototype.PASS = 0;
+        console.log(true);
+        console.log(0 in [ , ]);
+        console.log(true);
+        console.log("PASS" in { });
+        console.log("FAIL" in { });
+        console.log("toString" in { });
+        console.log(true);
+    }
+    expect_stdout: [
+        "true",
+        "false",
+        "true",
+        "true",
+        "false",
+        "true",
+        "true",
+    ]
+}
+
+issue_3997: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = function f(b) {
+            return b[b += this] = b;
+        }(0);
+        console.log(typeof a);
+    }
+    expect: {
+        var a = function f(b) {
+            return b[b += this] = b;
+        }(0);
+        console.log(typeof a);
+    }
+    expect_stdout: "string"
+}
+
+issue_4035: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        var a = 0;
+        (function() {
+            var b = --a;
+            console.log(delete (0 + b));
+            console.log(delete (1 * b));
+            console.log(delete (b + 0));
+            console.log(delete (b - 0));
+            console.log(delete (b / 1));
+        })();
+    }
+    expect: {
+        var a = 0;
+        (function() {
+            var b = --a;
+            console.log((0 + b, true));
+            console.log((1 * b, true));
+            console.log((0 + b, true));
+            console.log((b - 0, true));
+            console.log((b / 1, true));
+        })();
+    }
+    expect_stdout: [
+        "true",
+        "true",
+        "true",
+        "true",
+        "true",
+    ]
+}
+
+issue_4067: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+    }
+    input: {
+        (function(a) {
+            (function(b) {
+                b[0] += 0;
+                console.log(+a);
+            })(a);
+        })([]);
+    }
+    expect: {
+        (function(a) {
+            (function(b) {
+                b[0] += 0;
+                console.log(+a);
+            })(a);
+        })([]);
+    }
+    expect_stdout: "NaN"
+}
+
+issue_4077: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        console.log((a = []) - (a[0]++, 1) || "PASS");
+    }
+    expect: {
+        console.log((a = []) - (a[0]++, 1) || "PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4119_1: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var a, b;
+        b = a = [];
+        a[0] += 0;
+        if (+b + 1) {
+            console.log("FAIL");
+        } else {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        var a, b;
+        b = a = [];
+        a[0] += 0;
+        +b + 1 ? console.log("FAIL") : console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4119_2: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+    }
+    input: {
+        var a;
+        (function(b) {
+            a[0] += 0;
+            console.log(+b + 1 ? "FAIL" : "PASS");
+        })(a = []);
+    }
+    expect: {
+        var a;
+        (function(b) {
+            a[0] += 0;
+            console.log(+b + 1 ? "FAIL" : "PASS");
+        })(a = []);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4119_3: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var a, b;
+        b = a = {
+            p: 42,
+        };
+        delete a.p;
+        console.log(b.p ? "FAIL" : "PASS");
+    }
+    expect: {
+        var a, b;
+        b = a = {
+            p: 42,
+        };
+        delete a.p;
+        console.log(b.p ? "FAIL" : "PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4119_4: {
+    options = {
+        booleans: true,
+        conditionals: true,
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a, b;
+        b = a = {
+            p: 42,
+        };
+        delete a.p;
+        console.log(!b ? "FAIL" : "PASS");
+    }
+    expect: {
+        var a, b;
+        b = a = {
+            p: 42,
+        };
+        delete a.p;
+        console.log((b, 0, "PASS"));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4214: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            return function() {
+                try {
+                    return a;
+                } finally {
+                    var b = 0;
+                }
+            }(a++ && this());
+        }
+        var c = f();
+        console.log(c);
+    }
+    expect: {
+        var c = function(a) {
+            return function() {
+                try {
+                    return a;
+                } finally {}
+            }(a++ && this());
+        }();
+        console.log(c);
+    }
+    expect_stdout: "NaN"
+}
+
+issue_4271: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        ({
+            p: null,
+            q: (console.log("foo"), 42),
+            p: function() {}
+        })[console.log("bar"), "p"] && console.log("PASS");
+    }
+    expect: {
+        ({
+            p: null,
+            q: (console.log("foo"), 42),
+            p: function() {}
+        })[console.log("bar"), "p"],
+        console.log("PASS");
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+        "PASS",
+    ]
+}

test/compress/global_defs.js

@@ -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: {

test/compress/hoist_props.js

@@ -297,6 +297,33 @@ name_collision_3: {
     expect_stdout: "true 4 6"
 }
 
+name_collision_4: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function() {
+            var o = {
+                p: 0,
+                q: "PASS",
+            };
+            return function(o_p) {
+                if (!o.p) return o_p;
+            }(o.q);
+        }());
+    }
+    expect: {
+        console.log(function() {
+            var o_p$0 = 0, o_q = "PASS";
+            return function(o_p) {
+                if (!o_p$0) return o_p;
+            }(o_q);
+        }());
+    }
+    expect_stdout: "PASS"
+}
+
 contains_this_1: {
     options = {
         evaluate: true,
@@ -767,18 +794,17 @@ issue_3071_1: {
             var obj = {};
             obj.one = 1;
             obj.two = 2;
-            console.log(obj.one);
+            console.log(obj.one, obj.two);
         })();
     }
     expect: {
-        console.log(1);
+        console.log(1, 2);
     }
-    expect_stdout: "1"
+    expect_stdout: "1 2"
 }
 
 issue_3071_2: {
     options = {
-        evaluate: true,
         hoist_props: true,
         inline: true,
         join_vars: true,
@@ -793,19 +819,18 @@ issue_3071_2: {
             obj = {};
             obj.one = 1;
             obj.two = 2;
-            console.log(obj.one);
+            console.log(obj.one, obj.two);
             var obj;
         })();
     }
     expect: {
-        console.log(1);
+        console.log(1, 2);
     }
-    expect_stdout: "1"
+    expect_stdout: "1 2"
 }
 
 issue_3071_2_toplevel: {
     options = {
-        evaluate: true,
         hoist_props: true,
         inline: true,
         join_vars: true,
@@ -821,14 +846,14 @@ issue_3071_2_toplevel: {
             obj = {};
             obj.one = 1;
             obj.two = 2;
-            console.log(obj.one);
+            console.log(obj.one, obj.two);
             var obj;
         })();
     }
     expect: {
-        console.log(1);
+        console.log(1, 2);
     }
-    expect_stdout: "1"
+    expect_stdout: "1 2"
 }
 
 issue_3071_3: {
@@ -914,3 +939,132 @@ issue_3440: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3868: {
+    options = {
+        hoist_props: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        (function(t) {
+            t = {};
+            ({
+                get p() {},
+                q: (console.log("PASS"), +t),
+            }).r;
+        })();
+    }
+    expect: {
+        (function(t) {
+            t = {};
+            ({
+                get p() {},
+                q: (console.log("PASS"), +t),
+            }).r;
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3871: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function() {
+            do {
+                var b = {
+                    get null() {
+                        c;
+                    }
+                };
+            } while (!b);
+            return "PASS";
+        }());
+    }
+    expect: {
+        console.log(function() {
+            do {
+                var b = {
+                    get null() {
+                        c;
+                    }
+                };
+            } while (!b);
+            return "PASS";
+        }());
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3945_1: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+    }
+    input: {
+        function f() {
+            o.p;
+            var o = {
+                q: 0,
+            };
+        }
+    }
+    expect: {
+        function f() {
+            o.p;
+            var o = {
+                q: 0,
+            };
+        }
+    }
+}
+
+issue_3945_2: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        console.log(typeof o);
+        var o = {
+            p: 0,
+        };
+    }
+    expect: {
+        console.log(typeof o);
+        var o = {
+            p: 0,
+        };
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4023: {
+    options = {
+        comparisons: true,
+        hoist_props: true,
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+        typeofs: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            var a = function() {
+                return { p: 0 };
+            }();
+            return console.log("undefined" != typeof a);
+        }
+        f();
+    }
+    expect: {
+        console.log(void 0 !== {});
+    }
+    expect_stdout: "true"
+}

test/compress/ie8.js

@@ -588,7 +588,6 @@ issue_3197_1: {
         ie8: false,
     }
     input: {
-        var window = {};
         !function() {
             function Foo() {
                 console.log(this instanceof Foo);
@@ -598,7 +597,6 @@ issue_3197_1: {
         new window.Foo();
     }
     expect: {
-        var window = {};
         window.Foo = function o() {
             console.log(this instanceof o);
         };
@@ -619,7 +617,6 @@ issue_3197_1_ie8: {
         ie8: true,
     }
     input: {
-        var window = {};
         !function() {
             function Foo() {
                 console.log(this instanceof Foo);
@@ -629,7 +626,6 @@ issue_3197_1_ie8: {
         new window.Foo();
     }
     expect: {
-        var window = {};
         window.Foo = function Foo() {
             console.log(this instanceof Foo);
         };
@@ -2223,13 +2219,13 @@ issue_3523_rename_ie8: {
     expect: {
         var a = 0, b, c = "FAIL";
         (function() {
-            var c, n, t, o, a, r, f, i, u, e, h, l, v, y;
+            var c, n, t, o, a, r, e, f, i, u, h, l, v, y;
         })();
         try {
             throw 0;
         } catch (e) {
             (function() {
-                (function n() {
+                (function e() {
                     c = "PASS";
                 })();
             })();
@@ -2389,7 +2385,7 @@ issue_3703: {
         var a = "PASS";
         (function() {
             var b;
-            var c = function g() {
+            var c = function() {
                 a = "FAIL";
             };
             a ? b |= c : b.p;
@@ -2420,3 +2416,487 @@ issue_3750: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3823: {
+    options = {
+        ie8: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        for (var i = 0; i < 1; i++) {
+            var a = a ? function f() {
+                f;
+            } : 0;
+            console.log("PASS", typeof f);
+        }
+    }
+    expect: {
+        for (var i = 0; i < 1; i++) {
+            (function f() {
+                f;
+            });
+            console.log("PASS", typeof f);
+        }
+    }
+    expect_stdout: "PASS undefined"
+}
+
+issue_3825: {
+    options = {
+        ie8: true,
+        pure_getters: "strict",
+        side_effects: true,
+    }
+    input: {
+        console.log({}[void (0..length ? 1 : 2)]);
+    }
+    expect: {
+        console.log({}[void 0]);
+    }
+    expect_stdout: "undefined"
+}
+
+issue_3889: {
+    options = {
+        evaluate: true,
+        ie8: true,
+        reduce_vars: true,
+    }
+    input: {
+        function f(a) {
+            a = 0;
+            (function a() {
+                var a;
+                console.log(a);
+            })();
+        }
+        f();
+    }
+    expect: {
+        function f(a) {
+            a = 0;
+            (function a() {
+                var a;
+                console.log(a);
+            })();
+        }
+        f();
+    }
+    expect_stdout: "undefined"
+}
+
+issue_3918: {
+    options = {
+        conditionals: true,
+        ie8: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    mangle = {
+        ie8: true,
+    }
+    input: {
+        if (console.log("PASS")) {
+            var a = function f() {
+                f.p;
+                try {
+                    console.log("FAIL");
+                } catch (e) {}
+            }, b = a;
+        }
+    }
+    expect: {
+        var a;
+        console.log("PASS") && (a = function f() {
+            f.p;
+            try {
+                console.log("FAIL");
+            } catch (o) {}
+        }, a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3999: {
+    rename = true
+    mangle = {
+        ie8: true,
+    }
+    input: {
+        (function() {
+            (function f() {
+                for (var i = 0; i < 2; i++)
+                    try {
+                        f[0];
+                    } catch (f) {
+                        var f = 0;
+                        console.log(i);
+                    }
+            })();
+        })(typeof f);
+    }
+    expect: {
+        (function() {
+            (function f() {
+                for (var o = 0; o < 2; o++)
+                    try {
+                        f[0];
+                    } catch (f) {
+                        var f = 0;
+                        console.log(o);
+                    }
+            })();
+        })(typeof f);
+    }
+    expect_stdout: [
+        "0",
+        "1",
+    ]
+}
+
+issue_4001: {
+    options = {
+        collapse_vars: true,
+        ie8: true,
+        inline: true,
+        reduce_vars: true,
+        sequences: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            function f() {
+                return a;
+                var b;
+            }
+            var c = f();
+            (function g() {
+                c[42];
+                f;
+            })();
+            (function a() {});
+        }(42));
+    }
+    expect: {
+        function f() {
+            return a;
+        }
+        var a;
+        console.log((a = 42, void f()[42], void function a() {}));
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4015: {
+    rename = true
+    mangle = {
+        ie8: true,
+        toplevel: true,
+    }
+    input: {
+        var n, a = 0, b;
+        function f() {
+            try {
+                throw 0;
+            } catch (b) {
+                (function g() {
+                    (function b() {
+                        a++;
+                    })();
+                })();
+            }
+        }
+        f();
+        console.log(a);
+    }
+    expect: {
+        var n, o = 0, c;
+        function t() {
+            try {
+                throw 0;
+            } catch (c) {
+                (function n() {
+                    (function c() {
+                        o++;
+                    })();
+                })();
+            }
+        }
+        t();
+        console.log(o);
+    }
+    expect_stdout: "1"
+}
+
+issue_4019: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    mangle = {
+        ie8: true,
+        toplevel: true,
+    }
+    input: {
+        var a = function() {
+            try {
+                console.log("FAIL");
+            } catch (b) {}
+        }, a = (console.log(a.length), ++a);
+    }
+    expect: {
+        var o = function() {
+            try {
+                console.log("FAIL");
+            } catch (o) {}
+        }, o = (console.log(o.length), ++o);
+    }
+    expect_stdout: "0"
+}
+
+issue_4028: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    mangle = {
+        ie8: true,
+    }
+    input: {
+        function a() {
+            try {
+                A;
+            } catch (e) {}
+        }
+        var b = a += a;
+        console.log(typeof b);
+    }
+    expect: {
+        function a() {
+            try {
+                A;
+            } catch (a) {}
+        }
+        var b = a += a;
+        console.log(typeof b);
+    }
+    expect_stdout: "string"
+}
+
+issue_2737: {
+    options = {
+        ie8: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(a) {
+            a();
+        })(function f() {
+            console.log(typeof f);
+        });
+    }
+    expect: {
+        (function(a) {
+            a();
+        })(function f() {
+            console.log(typeof f);
+        });
+    }
+    expect_stdout: "function"
+}
+
+single_use_catch_redefined: {
+    options = {
+        ie8: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        try {
+            throw 2;
+        } catch (a) {
+            function g() {
+                return a;
+            }
+        }
+        console.log(g());
+    }
+    expect: {
+        var a = 1;
+        try {
+            throw 2;
+        } catch (a) {
+            function g() {
+                return a;
+            }
+        }
+        console.log(g());
+    }
+    expect_stdout: true
+}
+
+single_use_inline_catch_redefined: {
+    options = {
+        ie8: true,
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        try {
+            throw 2;
+        } catch (a) {
+            function g() {
+                return a;
+            }
+        }
+        console.log(g());
+    }
+    expect: {
+        var a = 1;
+        try {
+            throw 2;
+        } catch (a) {
+            function g() {
+                return a;
+            }
+        }
+        console.log(g());
+    }
+    expect_stdout: true
+}
+
+direct_inline_catch_redefined: {
+    options = {
+        ie8: true,
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 1;
+        function f() {
+            return a;
+        }
+        try {
+            throw 2;
+        } catch (a) {
+            function g() {
+                return a;
+            }
+            console.log(a, f(), g());
+        }
+        console.log(a, f(), g());
+    }
+    expect: {
+        var a = 1;
+        function f() {
+            return a;
+        }
+        try {
+            throw 2;
+        } catch (a) {
+            function g() {
+                return a;
+            }
+            console.log(a, f(), g());
+        }
+        console.log(a, a, g());
+    }
+    expect_stdout: true
+}
+
+issue_4186: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        ie8: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    mangle = {
+        ie8: true,
+        toplevel: true,
+    }
+    input: {
+        function f() {
+            (function NaN() {
+                var a = 1;
+                while (a--)
+                    try {} finally {
+                        console.log(0/0);
+                        var b;
+                    }
+            })(f);
+        }
+        f();
+        NaN;
+    }
+    expect: {
+        (function() {
+            (function NaN() {
+                var n = 1;
+                while (n--)
+                    console.log(0/0);
+            })();
+        })();
+        NaN;
+    }
+    expect_stdout: "NaN"
+}
+
+issue_4235: {
+    options = {
+        ie8: true,
+        unused: true,
+    }
+    input: {
+        try {} catch (e) {}
+        console.log(function e() {
+            var e = 0;
+        }());
+    }
+    expect: {
+        try {} catch (e) {}
+        console.log(function e() {}());
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4250: {
+    options = {
+        ie8: true,
+        loops: true,
+        unused: true,
+    }
+    input: {
+        console.log(function f() {
+            (function() {
+                for (f in "f");
+            })();
+            return f;
+            var f;
+        }());
+    }
+    expect: {
+        console.log(function f() {
+            (function() {
+                for (f in "f");
+            })();
+            return f;
+            var f;
+        }());
+    }
+    expect_stdout: "0"
+}

test/compress/if_return.js

@@ -573,3 +573,178 @@ issue_3600: {
     }
     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/issue-1034.js

@@ -39,7 +39,7 @@ non_hoisted_function_after_return: {
         "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]"
+        "WARN: Dropping unused function UnusedFunction [test/compress/issue-1034.js:11,21]",
     ]
 }
 
@@ -84,19 +84,16 @@ non_hoisted_function_after_return_2a: {
         }
     }
     expect_warnings: [
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:4,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:4,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:7,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:7,16]",
+        "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: 37",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:9,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:9,12]",
+        "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: 37, count: 18",
+        "INFO: pass 1: last_count: 35, count: 18",
     ]
 }
 
@@ -138,10 +135,7 @@ non_hoisted_function_after_return_2b: {
         }
     }
     expect_warnings: [
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:6,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:6,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:8,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:8,12]",
+        "WARN: Dropping initialization in unreachable code [test/compress/issue-1034.js:8,12]",
         "WARN: Dropping unreachable code [test/compress/issue-1034.js:12,12]",
     ]
 }
@@ -242,19 +236,16 @@ non_hoisted_function_after_return_2a_strict: {
     }
     expect_stdout: "5 6"
     expect_warnings: [
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:5,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:5,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:8,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:8,16]",
+        "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: 48",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:10,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:10,12]",
+        "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: 48, count: 29",
+        "INFO: pass 1: last_count: 46, count: 29",
     ]
 }
 
@@ -301,10 +292,7 @@ non_hoisted_function_after_return_2b_strict: {
     }
     expect_stdout: "5 6"
     expect_warnings: [
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:7,16]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:7,16]",
-        "WARN: Dropping unreachable code [test/compress/issue-1034.js:9,12]",
-        "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:9,12]",
+        "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-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

@@ -151,15 +151,18 @@ Infinity_not_in_with_scope: {
         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: {
@@ -167,15 +170,18 @@ Infinity_in_with_scope: {
         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: {

test/compress/issue-1639.js

@@ -22,8 +22,9 @@ issue_1639_1: {
         console.log(a, b);
     }
     expect: {
-        for (var a = 100, b = 10, L1 = 5; --L1 > 0;)
-            if (--b, 0) var ignore = 0;
+        for (var a = 100, b = 10, L1 = 5, ignore; --L1 > 0;) {
+            --b;
+        }
         console.log(a, b);
     }
     expect_stdout: "100 6"

test/compress/issue-1656.js

@@ -35,11 +35,7 @@ f7: {
         console.log(a, b);
     }
     expect_exact: [
-        "var b = 10;",
-        "",
-        "!function() {",
-        "    b = 100;",
-        "}(), console.log(100, b);",
+        "console.log(100, 100);",
     ]
-    expect_stdout: true
+    expect_stdout: "100 100"
 }

test/compress/keep_fargs.js

@@ -306,8 +306,6 @@ issue_2298: {
     expect: {
         !function() {
             (function() {
-                var a = undefined;
-                var undefined = a++;
                 try {
                     !function() {
                         (void 0)[1] = "foo";
@@ -527,7 +525,7 @@ issue_2506: {
         function f0(bar) {
             (function() {
                 (function() {
-                    if (false <= 0/0 & this >> 1 >= 0)
+                    if (false <= NaN & this >> 1 >= 0)
                         c++;
                 })(c++);
             })();
@@ -1226,8 +1224,7 @@ chained_3: {
     }
     expect: {
         console.log(function(b) {
-            var c = 1;
-            c = b;
+            var c = 1, c = b;
             b++;
             return c;
         }(2));
@@ -1455,3 +1452,37 @@ issue_3619: {
     }
     expect_stdout: "PASS"
 }
+
+issue_4353_1: {
+    options = {
+        keep_fargs: "strict",
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function f(a) {}.length);
+    }
+    expect: {
+        console.log(function(a) {}.length);
+    }
+    expect_stdout: "1"
+}
+
+issue_4353_2: {
+    options = {
+        keep_fargs: "strict",
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function f(a) {
+            while (console.log("PASS"));
+        })();
+    }
+    expect: {
+        (function() {
+            while (console.log("PASS"));
+        })();
+    }
+    expect_stdout: "PASS"
+}

test/compress/labels.js

@@ -3,6 +3,7 @@ labels_1: {
         conditionals: true,
         dead_code: true,
         if_return: true,
+        unused: true,
     }
     input: {
         out: {
@@ -21,6 +22,7 @@ labels_2: {
         conditionals: true,
         dead_code: true,
         if_return: true,
+        unused: true,
     }
     input: {
         out: {
@@ -61,6 +63,7 @@ labels_4: {
         conditionals: true,
         dead_code: true,
         if_return: true,
+        unused: true,
     }
     input: {
         out: for (var i = 0; i < 5; ++i) {
@@ -105,6 +108,9 @@ labels_5: {
 }
 
 labels_6: {
+    options = {
+        dead_code: true,
+    }
     input: {
         out: break out;
     };
@@ -159,6 +165,7 @@ labels_9: {
         conditionals: true,
         dead_code: true,
         if_return: true,
+        unused: true,
     }
     input: {
         out: while (foo) {

test/compress/loops.js

@@ -201,7 +201,7 @@ evaluate: {
     }
 }
 
-issue_1532: {
+issue_1532_1: {
     options = {
         evaluate: true,
         loops: true,
@@ -210,18 +210,56 @@ issue_1532: {
         function f(x, y) {
             do {
                 if (x) break;
-                foo();
+                console.log(y);
             } while (false);
         }
+        f(null, "PASS");
+        f(42, "FAIL");
+    }
+    expect: {
+        function f(x, y) {
+            for (; !x && (console.log(y), false););
+        }
+        f(null, "PASS");
+        f(42, "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_1532_2: {
+    options = {
+        evaluate: true,
+        loops: true,
+    }
+    input: {
+        function f(x, y) {
+            do {
+                if (x) {
+                    console.log(x);
+                    break;
+                }
+                console.log(y);
+            } while (false);
+        }
+        f(null, "PASS");
+        f(42, "FAIL");
     }
     expect: {
         function f(x, y) {
             do {
-                if (x) break;
-                foo();
-            } while (false);
+                if (x) {
+                    console.log(x);
+                    break;
                 }
+            } while (console.log(y), false);
         }
+        f(null, "PASS");
+        f(42, "FAIL");
+    }
+    expect_stdout: [
+        "PASS",
+        "42",
+    ]
 }
 
 issue_186: {
@@ -509,8 +547,8 @@ dead_code_condition: {
         console.log(a);
     }
     expect: {
-        var c;
         var a = 0, b = 5;
+        var c;
         a += 1, 0,
         console.log(a);
     }
@@ -549,6 +587,7 @@ issue_2740_2: {
         dead_code: true,
         loops: true,
         passes: 2,
+        unused: true,
     }
     input: {
         L1: while (x()) {
@@ -564,6 +603,7 @@ issue_2740_3: {
     options = {
         dead_code: true,
         loops: true,
+        unused: true,
     }
     input: {
         L1: for (var x = 0; x < 3; x++) {
@@ -589,6 +629,7 @@ issue_2740_4: {
         dead_code: true,
         loops: true,
         passes: 2,
+        unused: true,
     }
     input: {
         L1: for (var x = 0; x < 3; x++) {
@@ -613,6 +654,7 @@ issue_2740_5: {
         dead_code: true,
         loops: true,
         passes: 2,
+        unused: true,
     }
     input: {
         L1: for (var x = 0; x < 3; x++) {
@@ -752,7 +794,37 @@ empty_for_in_side_effects: {
     expect_warnings: [
         "WARN: Dropping unused variable b [test/compress/loops.js:4,16]",
         "INFO: Dropping unused loop variable a [test/compress/loops.js:1,17]",
-        "WARN: Side effects in object of for-in loop [test/compress/loops.js:1,17]",
+        "WARN: Side effects in object of for-in loop [test/compress/loops.js:2,17]",
+    ]
+}
+
+empty_for_in_prop_init: {
+    options = {
+        loops: true,
+        pure_getters: "strict",
+        unused: true,
+    }
+    input: {
+        console.log(function f() {
+            var a = "bar";
+            for ((a, f)[a] in console.log("foo"));
+            return a;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            var a = "bar";
+            console.log("foo");
+            return a;
+        }());
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    expect_warnings: [
+        "INFO: Dropping unused loop variable f [test/compress/loops.js:3,21]",
+        "WARN: Side effects in object of for-in loop [test/compress/loops.js:3,30]",
     ]
 }
 
@@ -763,6 +835,7 @@ issue_3631_1: {
         loops: true,
         reduce_vars: true,
         toplevel: true,
+        unused: true,
     }
     input: {
         var c = 0;
@@ -789,6 +862,7 @@ issue_3631_2: {
         loops: true,
         reduce_vars: true,
         toplevel: true,
+        unused: true,
     }
     input: {
         L: for (var a = 1; a--; console.log(b)) {
@@ -927,3 +1001,282 @@ issue_3634_2: {
     }
     expect_stdout: "1"
 }
+
+issue_4075: {
+    options = {
+        loops: true,
+        unused: true,
+    }
+    input: {
+        var a = "FAIL";
+        (function() {
+            for (a in { PASS: 0 });
+        })()
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        (function() {
+            for (a in { PASS: 0 });
+        })()
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4082: {
+    options = {
+        keep_fargs: "strict",
+        loops: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        (function(a) {
+            for (a in "foo")
+                var b;
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        (function(a) {
+            for (a in "foo");
+        })();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4084: {
+    options = {
+        keep_fargs: "strict",
+        loops: true,
+        passes: 2,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            function f(a) {
+                var b = a++;
+                for (a in "foo");
+            }
+            f();
+            return typeof a;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            (function() {
+                0;
+            })();
+            return typeof a;
+        }());
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4091_1: {
+    options = {
+        loops: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        try {
+            throw "FAIL";
+        } catch (e) {
+            for (var e in 42);
+        }
+        console.log(e && e);
+    }
+    expect: {
+        try {
+            throw "FAIL";
+        } catch (e) {
+            var e;
+        }
+        console.log(e && e);
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4091_2: {
+    options = {
+        loops: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        try {
+            throw "FAIL";
+        } catch (e) {
+            for (e in 42);
+            var e;
+        }
+        console.log(e && e);
+    }
+    expect: {
+        try {
+            throw "FAIL";
+        } catch (e) {
+            var e;
+        }
+        console.log(e && e);
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4182_1: {
+    options = {
+        loops: true,
+    }
+    input: {
+        (function() {
+            do {
+                try {
+                    return;
+                } finally {
+                    continue;
+                }
+                console.log("FAIL");
+            } while (0);
+            console.log("PASS");
+        })();
+    }
+    expect: {
+        (function() {
+            do {
+                try {
+                    return;
+                } finally {
+                    continue;
+                }
+                console.log("FAIL");
+            } while (0);
+            console.log("PASS");
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4182_2: {
+    options = {
+        loops: true,
+    }
+    input: {
+        (function() {
+            L: do {
+                do {
+                    try {
+                        return;
+                    } finally {
+                        continue L;
+                    }
+                    console.log("FAIL");
+                } while (0);
+                console.log("FAIL");
+            } while (0);
+            console.log("PASS");
+        })();
+    }
+    expect: {
+        (function() {
+            L: do {
+                do {
+                    try {
+                        return;
+                    } finally {
+                        continue L;
+                    }
+                } while (console.log("FAIL"), 0);
+                console.log("FAIL");
+            } while (0);
+            console.log("PASS");
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+do_continue: {
+    options = {
+        loops: true,
+    }
+    input: {
+        try {
+            do {
+                continue;
+            } while ([ A ]);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            do {
+                continue;
+            } while ([ A ]);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4240: {
+    options = {
+        loops: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(a) {
+            function f() {
+                var o = { PASS: 42 };
+                for (a in o);
+            }
+            (function() {
+                if (f());
+            })();
+            console.log(a);
+        })();
+    }
+    expect: {
+        (function(a) {
+            (function() {
+                if (function() {
+                    for (a in { PASS: 42 });
+                }());
+            })();
+            console.log(a);
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4355: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        while (function() {
+            var a;
+            for (a in console.log("PASS"))
+                var b = 0;
+        }())
+            var c;
+    }
+    expect: {
+        (function() {
+            console.log("PASS");
+        })();
+        var c;
+    }
+    expect_stdout: "PASS"
+}

test/compress/numbers.js

@@ -1,49 +1,100 @@
-hex_numbers_in_parentheses_for_prototype_functions: {
+parentheses_for_prototype_functions: {
     beautify = {
         beautify: true,
     }
     input: {
-        function f() {
-            (-2);
-            (-2).toFixed(0);
+        (function() {
+            console.log((-2));
+            console.log((-2).toFixed(0));
 
-            (2);
-            (2).toFixed(0);
+            console.log((2));
+            console.log((2).toFixed(0));
 
-            (0.2);
-            (0.2).toFixed(0);
+            console.log((0.2));
+            console.log((0.2).toFixed(0));
 
-            (2.34e20);
-            (2.34e20).toFixed(0);
+            console.log((2.34e20));
+            console.log((2.34e20).toFixed(0));
 
-            (0.00000002);
-            (0.00000002).toFixed(0);
+            console.log((0.00000002));
+            console.log((0.00000002).toFixed(0));
 
-            (1000000000000000128);
-            (1000000000000000128).toFixed(0);
+            console.log((1000000000000000128));
+            console.log((1000000000000000128).toFixed(0));
 
-            (-1000000000000000128);
-            (-1000000000000000128).toFixed(0);
-        }
+            console.log((-1000000000000000128));
+            console.log((-1000000000000000128).toFixed(0));
+        })();
     }
     expect_exact: [
-        "function f() {",
-        "    -2;",
-        "    (-2).toFixed(0);",
-        "    2;",
-        "    2..toFixed(0);",
-        "    .2;",
-        "    .2.toFixed(0);",
-        "    234e18;",
-        "    234e18.toFixed(0);",
-        "    2e-8;",
-        "    2e-8.toFixed(0);",
-        "    0xde0b6b3a7640080;",
-        "    (0xde0b6b3a7640080).toFixed(0);",
-        "    -0xde0b6b3a7640080;",
-        "    (-0xde0b6b3a7640080).toFixed(0);",
-        "}",
+        "(function() {",
+        "    console.log(-2);",
+        "    console.log((-2).toFixed(0));",
+        "    console.log(2);",
+        "    console.log(2..toFixed(0));",
+        "    console.log(.2);",
+        "    console.log(.2.toFixed(0));",
+        "    console.log(234e18);",
+        "    console.log(234e18.toFixed(0));",
+        "    console.log(2e-8);",
+        "    console.log(2e-8.toFixed(0));",
+        "    console.log(0xde0b6b3a7640080);",
+        "    console.log(0xde0b6b3a7640080.toFixed(0));",
+        "    console.log(-0xde0b6b3a7640080);",
+        "    console.log((-0xde0b6b3a7640080).toFixed(0));",
+        "})();",
     ]
+    expect_stdout: true
+}
+
+parentheses_for_prototype_functions_galio: {
+    beautify = {
+        beautify: true,
+        galio: true,
+    }
+    input: {
+        (function() {
+            console.log((-2));
+            console.log((-2).toFixed(0));
+
+            console.log((2));
+            console.log((2).toFixed(0));
+
+            console.log((0.2));
+            console.log((0.2).toFixed(0));
+
+            console.log((2.34e20));
+            console.log((2.34e20).toFixed(0));
+
+            console.log((0.00000002));
+            console.log((0.00000002).toFixed(0));
+
+            console.log((1000000000000000128));
+            console.log((1000000000000000128).toFixed(0));
+
+            console.log((-1000000000000000128));
+            console.log((-1000000000000000128).toFixed(0));
+        })();
+    }
+    expect_exact: [
+        "(function() {",
+        "    console.log(-2);",
+        "    console.log((-2).toFixed(0));",
+        "    console.log(2);",
+        "    console.log(2..toFixed(0));",
+        "    console.log(.2);",
+        "    console.log(.2.toFixed(0));",
+        "    console.log(234e18);",
+        "    console.log(234e18.toFixed(0));",
+        "    console.log(2e-8);",
+        "    console.log(2e-8.toFixed(0));",
+        "    console.log(0xde0b6b3a7640080);",
+        "    console.log((0xde0b6b3a7640080).toFixed(0));",
+        "    console.log(-0xde0b6b3a7640080);",
+        "    console.log((-0xde0b6b3a7640080).toFixed(0));",
+        "})();",
+    ]
+    expect_stdout: true
 }
 
 comparisons: {
@@ -91,7 +142,7 @@ evaluate_1: {
     expect: {
         console.log(
             x + 1 + 2,
-            2 * x,
+            2 * +x,
             +x + 1 + 2,
             1 + x + 2 + 3,
             3 | x,
@@ -130,7 +181,7 @@ evaluate_1_unsafe_math: {
     expect: {
         console.log(
             x + 1 + 2,
-            2 * x,
+            2 * +x,
             +x + 3,
             1 + x + 2 + 3,
             3 | x,
@@ -148,10 +199,12 @@ evaluate_1_unsafe_math: {
 evaluate_2: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: false,
     }
     input: {
-        var x = "42", y = null;
+        function f(num) {
+            var x = "" + num, y = null;
             [
                 x + 1 + 2,
                 x * 1 * 2,
@@ -169,25 +222,30 @@ evaluate_2: {
                 console.log(typeof n, n);
             });
         }
+        f(42);
+    }
     expect: {
-        var x = "42", y = null;
+        function f(num) {
+            var x = "" + num, y = null;
             [
-            x + 1 + 2,
+                x + "12",
                 2 * x,
                 +x + 1 + 2,
-            1 + x + 2 + 3,
+                1 + x + "23",
                 3 | x,
                 1 + x-- + 2 + 3,
                 x*y + 2 + 1 + 3,
-            1 + (2 + x + 3),
+                2 + x + 3 + 1,
                 2 + ~x + 3 + 1,
-            2 + ~x + 3 - y,
+                2 + ~x + 3,
                 0 & x,
                 2 + (x |= 0) + 3 + 1,
             ].forEach(function(n) {
                 console.log(typeof n, n);
             });
         }
+        f(42);
+    }
     expect_stdout: [
         "string 4212",
         "number 84",
@@ -207,10 +265,12 @@ evaluate_2: {
 evaluate_2_unsafe_math: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: true,
     }
     input: {
-        var x = "42", y = null;
+        function f(num) {
+            var x = "" + num, y = null;
             [
                 x + 1 + 2,
                 x * 1 * 2,
@@ -228,25 +288,30 @@ evaluate_2_unsafe_math: {
                 console.log(typeof n, n);
             });
         }
+        f(42);
+    }
     expect: {
-        var x = "42", y = null;
+        function f(num) {
+            var x = "" + num, y = null;
             [
-            x + 1 + 2,
+                x + "12",
                 2 * x,
                 +x + 3,
-            1 + x + 2 + 3,
+                1 + x + "23",
                 3 | x,
                 6 + x--,
                 x*y + 6,
-            1 + (2 + x + 3),
+                6 + x,
                 6 + ~x,
-            5 + ~x - y,
+                5 + ~x,
                 0 & x,
                 6 + (x |= 0),
             ].forEach(function(n) {
                 console.log(typeof n, n);
             });
         }
+        f(42);
+    }
     expect_stdout: [
         "string 4212",
         "number 84",
@@ -310,10 +375,12 @@ evaluate_4: {
 evaluate_5: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: false,
     }
     input: {
-        var a = "1";
+        function f(num) {
+            var a = "" + num;
             [
                 +a + 2 + 3,
                 +a + 2 - 3,
@@ -331,8 +398,11 @@ evaluate_5: {
                 console.log(typeof n, n);
             });
         }
+        f(1);
+    }
     expect: {
-        var a = "1";
+        function f(num) {
+            var a = "" + num;
             [
                 +a + 2 + 3,
                 +a + 2 - 3,
@@ -350,6 +420,8 @@ evaluate_5: {
                 console.log(typeof n, n);
             });
         }
+        f(1);
+    }
     expect_stdout: [
         "number 6",
         "number 0",
@@ -369,10 +441,12 @@ evaluate_5: {
 evaluate_5_unsafe_math: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: true,
     }
     input: {
-        var a = "1";
+        function f(num) {
+            var a = "" + num;
             [
                 +a + 2 + 3,
                 +a + 2 - 3,
@@ -390,8 +464,11 @@ evaluate_5_unsafe_math: {
                 console.log(typeof n, n);
             });
         }
+        f(1);
+    }
     expect: {
-        var a = "1";
+        function f(num) {
+            var a = "" + num;
             [
                 +a + 5,
                 +a + -1,
@@ -409,6 +486,8 @@ evaluate_5_unsafe_math: {
                 console.log(typeof n, n);
             });
         }
+        f(1);
+    }
     expect_stdout: [
         "number 6",
         "number 0",
@@ -546,10 +625,12 @@ evaluate_6_unsafe_math: {
 evaluate_7: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: false,
     }
     input: {
-        var x = "42", y;
+        function f(num, y) {
+            var x = "" + num;
             [
                 +x + 2 + (3 + !y),
                 +x + 2 + (3 - !y),
@@ -563,8 +644,11 @@ evaluate_7: {
                 console.log(typeof n, n);
             });
         }
+        f(42);
+    }
     expect: {
-        var x = "42", y;
+        function f(num, y) {
+            var x = "" + num;
             [
                 +x + 2 + (3 + !y),
                 +x + 2 + (3 - !y),
@@ -578,6 +662,8 @@ evaluate_7: {
                 console.log(typeof n, n);
             });
         }
+        f(42);
+    }
     expect_stdout: [
         "number 48",
         "number 46",
@@ -593,10 +679,12 @@ evaluate_7: {
 evaluate_7_unsafe_math: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: true,
     }
     input: {
-        var x = "42", y;
+        function f(num, y) {
+            var x = "" + num;
             [
                 +x + 2 + (3 + !y),
                 +x + 2 + (3 - !y),
@@ -610,8 +698,11 @@ evaluate_7_unsafe_math: {
                 console.log(typeof n, n);
             });
         }
+        f(42);
+    }
     expect: {
-        var x = "42", y;
+        function f(num, y) {
+            var x = "" + num;
             [
                 +x + 5 + !y,
                 +x + 5 - !y,
@@ -625,6 +716,8 @@ evaluate_7_unsafe_math: {
                 console.log(typeof n, n);
             });
         }
+        f(42);
+    }
     expect_stdout: [
         "number 48",
         "number 46",
@@ -637,6 +730,22 @@ evaluate_7_unsafe_math: {
     ]
 }
 
+evaluate_8_unsafe_math: {
+    options = {
+        evaluate: true,
+        unsafe_math: true,
+    }
+    input: {
+        var a = [ "42" ];
+        console.log(a * (1 / 7));
+    }
+    expect: {
+        var a = [ "42" ];
+        console.log(+a / 7);
+    }
+    expect_stdout: "6"
+}
+
 NaN_redefined: {
     options = {
         evaluate: true,
@@ -1251,3 +1360,29 @@ issue_3695: {
     }
     expect_stdout: "NaN"
 }
+
+issue_4137: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log(+(A = []) * (A[0] = 1));
+    }
+    expect: {
+        console.log(+(A = []) * (A[0] = 1));
+    }
+    expect_stdout: "0"
+}
+
+issue_4142: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log("" + +(0 === console));
+    }
+    expect: {
+        console.log("" + +(0 === console));
+    }
+    expect_stdout: "0"
+}

test/compress/objects.js

@@ -45,8 +45,8 @@ duplicate_key_strict: {
         "use strict";
         var o = {
             a: 1,
-            b: 2,
             a: 3,
+            b: 2,
         };
         for (var k in o)
             console.log(k, o[k]);
@@ -221,3 +221,195 @@ numeric_literal: {
         "8 7 8",
     ]
 }
+
+evaluate_computed_key: {
+    options = {
+        evaluate: true,
+        objects: true,
+    }
+    input: {
+        console.log({
+            ["foo" + "bar"]: "PASS",
+        }.foobar);
+    }
+    expect: {
+        console.log({
+            foobar: "PASS",
+        }.foobar);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+keep_computed_key: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        ({
+            [console.log("PASS")]: 42,
+        });
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4269_1: {
+    options = {
+        evaluate: true,
+        objects: true,
+    }
+    input: {
+        console.log({
+            get 0() {
+                return "FAIL";
+            },
+            [0]: "PASS",
+        }[0]);
+    }
+    expect: {
+        console.log({
+            get 0() {
+                return "FAIL";
+            },
+            [0]: "PASS",
+        }[0]);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4269_2: {
+    options = {
+        evaluate: true,
+        objects: true,
+    }
+    input: {
+        console.log({
+            get [0]() {
+                return "FAIL";
+            },
+            0: "PASS",
+        }[0]);
+    }
+    expect: {
+        console.log({
+            get [0]() {
+                return "FAIL";
+            },
+            0: "PASS",
+        }[0]);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4269_3: {
+    options = {
+        evaluate: true,
+        objects: true,
+    }
+    input: {
+        console.log({
+            ["foo"]: "bar",
+            get 42() {
+                return "FAIL";
+            },
+            42: "PASS",
+        }[42]);
+    }
+    expect: {
+        console.log({
+            foo: "bar",
+            get [42]() {
+                return "FAIL";
+            },
+            42: "PASS",
+        }[42]);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4269_4: {
+    options = {
+        evaluate: true,
+        objects: true,
+    }
+    input: {
+        console.log({
+            get 42() {
+                return "FAIL";
+            },
+            ["foo"]: "bar",
+            42: "PASS",
+        }[42]);
+    }
+    expect: {
+        console.log({
+            get 42() {
+                return "FAIL";
+            },
+            foo: "bar",
+            [42]: "PASS",
+        }[42]);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4269_5: {
+    options = {
+        evaluate: true,
+        objects: true,
+    }
+    input: {
+        console.log({
+            get 42() {
+                return "FAIL";
+            },
+            [console]: "bar",
+            42: "PASS",
+        }[42]);
+    }
+    expect: {
+        console.log({
+            get 42() {
+                return "FAIL";
+            },
+            [console]: "bar",
+            42: "PASS",
+        }[42]);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4380: {
+    options = {
+        evaluate: true,
+        objects: true,
+    }
+    input: {
+        console.log({
+            get 0() {
+                return "FAIL 1";
+            },
+            0: "FAIL 2",
+            [0]: "PASS",
+        }[0]);
+    }
+    expect: {
+        console.log({
+            get 0() {
+                return "FAIL 1";
+            },
+            [0]: ("FAIL 2", "PASS"),
+        }[0]);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}

test/compress/properties.js

@@ -130,7 +130,7 @@ evaluate_string_length: {
     }
 }
 
-mangle_properties: {
+mangle_properties_1: {
     mangle = {
         properties: {
             keep_quoted: false,
@@ -152,6 +152,53 @@ mangle_properties: {
     }
 }
 
+mangle_properties_2: {
+    mangle = {
+        properties: {
+            reserved: [
+                "value",
+            ]
+        },
+    }
+    input: {
+        var o = {
+            prop1: 1,
+        };
+        Object.defineProperty(o, "prop2", {
+            value: 2,
+        });
+        Object.defineProperties(o, {
+            prop3: {
+                value: 3,
+            },
+        });
+        console.log("prop1", o.prop1, "prop1" in o);
+        console.log("prop2", o.prop2, o.hasOwnProperty("prop2"));
+        console.log("prop3", o.prop3, Object.getOwnPropertyDescriptor(o, "prop3").value);
+    }
+    expect: {
+        var o = {
+            o: 1,
+        };
+        Object.defineProperty(o, "p", {
+            value: 2,
+        });
+        Object.defineProperties(o, {
+            r: {
+                value: 3,
+            },
+        });
+        console.log("prop1", o.o, "o" in o);
+        console.log("prop2", o.p, o.hasOwnProperty("p"));
+        console.log("prop3", o.r, Object.getOwnPropertyDescriptor(o, "r").value);
+    }
+    expect_stdout: [
+        "prop1 1 true",
+        "prop2 2 true",
+        "prop3 3 3",
+    ]
+}
+
 mangle_unquoted_properties: {
     options = {
         evaluate: true,
@@ -1046,16 +1093,22 @@ array_hole: {
         side_effects: true,
     }
     input: {
-        console.log(
-            [ 1, 2, , 3][1],
-            [ 1, 2, , 3][2],
-            [ 1, 2, , 3][3]
-        );
+        Array.prototype[2] = "PASS";
+        console.log([ 1, 2, , 3 ][1]);
+        console.log([ 1, 2, , 3 ][2]);
+        console.log([ 1, 2, , 3 ][3]);
     }
     expect: {
-        console.log(2, void 0, 3);
+        Array.prototype[2] = "PASS";
+        console.log(2);
+        console.log([ , , , ][2]);
+        console.log(3);
     }
-    expect_stdout: "2 undefined 3"
+    expect_stdout: [
+        "2",
+        "PASS",
+        "3",
+    ]
 }
 
 new_this: {
@@ -1070,11 +1123,7 @@ new_this: {
             }
         }.f(42);
     }
-    expect: {
-        new function(a) {
-            this.a = a;
-        }(42);
-    }
+    expect: {}
 }
 
 issue_2513: {
@@ -1143,558 +1192,6 @@ const_prop_assign_pure: {
     }
 }
 
-join_object_assignments_1: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var x = {
-                a: 1,
-                c: (console.log("c"), "C"),
-            };
-            x.b = 2;
-            x[3] = function() {
-                console.log(x);
-            },
-            x["a"] = /foo/,
-            x.bar = x;
-            return x;
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var x = {
-                a: 1,
-                c: (console.log("c"), "C"),
-                b: 2,
-                3: function() {
-                    console.log(x);
-                },
-                a: /foo/,
-            };
-            x.bar = x;
-            return x;
-        }());
-    }
-    expect_stdout: true
-}
-
-join_object_assignments_2: {
-    options = {
-        evaluate: true,
-        hoist_props: true,
-        join_vars: true,
-        passes: 3,
-        reduce_vars: true,
-        toplevel: true,
-        unused: true,
-    }
-    input: {
-        var o = {
-            foo: 1,
-        };
-        o.bar = 2;
-        o.baz = 3;
-        console.log(o.foo, o.bar + o.bar, o.foo * o.bar * o.baz);
-    }
-    expect: {
-        console.log(1, 4, 6);
-    }
-    expect_stdout: "1 4 6"
-}
-
-join_object_assignments_3: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {
-                a: "PASS",
-            }, a = o.a;
-            o.a = "FAIL";
-            return a;
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var o = {
-                a: "PASS",
-            }, a = o.a;
-            o.a = "FAIL";
-            return a;
-        }());
-    }
-    expect_stdout: "PASS"
-}
-
-join_object_assignments_4: {
-    options = {
-        join_vars: true,
-        sequences: true,
-    }
-    input: {
-        var o;
-        console.log(o);
-        o = {};
-        o.a = "foo";
-        console.log(o.b);
-        o.b = "bar";
-        console.log(o.a);
-    }
-    expect: {
-        var o;
-        console.log(o),
-        o = {
-            a: "foo",
-        },
-        console.log(o.b),
-        o.b = "bar",
-        console.log(o.a);
-    }
-    expect_stdout: [
-        "undefined",
-        "undefined",
-        "foo",
-    ]
-}
-
-join_object_assignments_return_1: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {
-                p: 3
-            };
-            return o.q = "foo";
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var o = {
-                p: 3,
-                q: "foo"
-            };
-            return o.q;
-        }());
-    }
-    expect_stdout: "foo"
-}
-
-join_object_assignments_return_2: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {
-                p: 3
-            };
-            return o.q = /foo/,
-            o.r = "bar";
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var o = {
-                p: 3,
-                q: /foo/,
-                r: "bar"
-            };
-            return o.r;
-        }());
-    }
-    expect_stdout: "bar"
-}
-
-join_object_assignments_return_3: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {
-                p: 3
-            };
-            return o.q = "foo",
-            o.p += "",
-            console.log(o.q),
-            o.p;
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var o = {
-                p: 3,
-                q: "foo"
-            };
-            return o.p += "",
-            console.log(o.q),
-            o.p;
-        }());
-    }
-    expect_stdout: [
-        "foo",
-        "3",
-    ]
-}
-
-join_object_assignments_for: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {
-                p: 3
-            };
-            for (o.q = "foo"; console.log(o.q););
-            return o.p;
-        }());
-    }
-    expect: {
-        console.log(function() {
-            for (var o = {
-                p: 3,
-                q: "foo"
-            }; console.log(o.q););
-            return o.p;
-        }());
-    }
-    expect_stdout: [
-        "foo",
-        "3",
-    ]
-}
-
-join_object_assignments_if: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {};
-            if (o.a = "PASS") return o.a;
-        }())
-    }
-    expect: {
-        console.log(function() {
-            var o = { a: "PASS" };
-            if (o.a) return o.a;
-        }());
-    }
-    expect_stdout: "PASS"
-}
-
-join_object_assignments_forin: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {};
-            for (var a in o.a = "PASS", o)
-                return o[a];
-        }())
-    }
-    expect: {
-        console.log(function() {
-            var o = { a: "PASS" };
-            for (var a in o)
-                return o[a];
-        }());
-    }
-    expect_stdout: "PASS"
-}
-
-join_object_assignments_negative: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[0] = 0;
-        o[-0] = 1;
-        o[-1] = 2;
-        console.log(o[0], o[-0], o[-1]);
-    }
-    expect: {
-        var o = {
-            0: 0,
-            0: 1,
-            "-1": 2
-        };
-        console.log(o[0], o[-0], o[-1]);
-    }
-    expect_stdout: "1 1 2"
-}
-
-join_object_assignments_NaN_1: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        var o = {};
-        o[NaN] = 1;
-        o[0/0] = 2;
-        console.log(o[NaN], o[NaN]);
-    }
-    expect: {
-        var o = {};
-        o[NaN] = 1;
-        o[0/0] = 2;
-        console.log(o[NaN], o[NaN]);
-    }
-    expect_stdout: "2 2"
-}
-
-join_object_assignments_NaN_2: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[NaN] = 1;
-        o[0/0] = 2;
-        console.log(o[NaN], o[NaN]);
-    }
-    expect: {
-        var o = {
-            NaN: 1,
-            NaN: 2
-        };
-        console.log(o.NaN, o.NaN);
-    }
-    expect_stdout: "2 2"
-}
-
-join_object_assignments_null_0: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        var o = {};
-        o[null] = 1;
-        console.log(o[null]);
-    }
-    expect: {
-        var o = {};
-        o[null] = 1;
-        console.log(o[null]);
-    }
-    expect_stdout: "1"
-}
-
-join_object_assignments_null_1: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[null] = 1;
-        console.log(o[null]);
-    }
-    expect: {
-        var o = {
-            null: 1
-        };
-        console.log(o.null);
-    }
-    expect_stdout: "1"
-}
-
-join_object_assignments_void_0: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-    }
-    input: {
-        var o = {};
-        o[void 0] = 1;
-        console.log(o[void 0]);
-    }
-    expect: {
-        var o = {
-            undefined: 1
-        };
-        console.log(o[void 0]);
-    }
-    expect_stdout: "1"
-}
-
-join_object_assignments_undefined_1: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        var o = {};
-        o[undefined] = 1;
-        console.log(o[undefined]);
-    }
-    expect: {
-        var o = {};
-        o[void 0] = 1;
-        console.log(o[void 0]);
-    }
-    expect_stdout: "1"
-}
-
-join_object_assignments_undefined_2: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[undefined] = 1;
-        console.log(o[undefined]);
-    }
-    expect: {
-        var o = {
-            undefined : 1
-        };
-        console.log(o[void 0]);
-    }
-    expect_stdout: "1"
-}
-
-join_object_assignments_Infinity: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[Infinity] = 1;
-        o[1/0] = 2;
-        o[-Infinity] = 3;
-        o[-1/0] = 4;
-        console.log(o[Infinity], o[1/0], o[-Infinity], o[-1/0]);
-    }
-    expect: {
-        var o = {
-            Infinity: 1,
-            Infinity: 2,
-            "-Infinity": 3,
-            "-Infinity": 4
-        };
-        console.log(o[1/0], o[1/0], o[-1/0], o[-1/0]);
-    }
-    expect_stdout: "2 2 4 4"
-}
-
-join_object_assignments_regex: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[/rx/] = 1;
-        console.log(o[/rx/]);
-    }
-    expect: {
-        var o = {
-            "/rx/": 1
-        };
-        console.log(o[/rx/]);
-    }
-    expect_stdout: "1"
-}
-
-issue_2816: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        "use strict";
-        var o = {
-            a: 1
-        };
-        o.b = 2;
-        o.a = 3;
-        o.c = 4;
-        console.log(o.a, o.b, o.c);
-    }
-    expect: {
-        "use strict";
-        var o = {
-            a: 1,
-            b: 2
-        };
-        o.a = 3;
-        o.c = 4;
-        console.log(o.a, o.b, o.c);
-    }
-    expect_stdout: "3 2 4"
-}
-
-issue_2893_1: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        var o = {
-            get a() {
-                return "PASS";
-            },
-        };
-        o.a = "FAIL";
-        console.log(o.a);
-    }
-    expect: {
-        var o = {
-            get a() {
-                return "PASS";
-            },
-        };
-        o.a = "FAIL";
-        console.log(o.a);
-    }
-    expect_stdout: "PASS"
-}
-
-issue_2893_2: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        var o = {
-            set a(v) {
-                this.b = v;
-            },
-            b: "FAIL",
-        };
-        o.a = "PASS";
-        console.log(o.b);
-    }
-    expect: {
-        var o = {
-            set a(v) {
-                this.b = v;
-            },
-            b: "FAIL",
-        };
-        o.a = "PASS";
-        console.log(o.b);
-    }
-    expect_stdout: "PASS"
-}
-
 issue_869_1: {
     mangle = {
         properties: {
@@ -1856,36 +1353,6 @@ issue_3188_3: {
     expect_stdout: "PASS"
 }
 
-join_expr: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-    }
-    input: {
-        var c = "FAIL";
-        (function() {
-            var a = 0;
-            switch ((a = {}) && (a.b = 0)) {
-              case 0:
-                c = "PASS";
-            }
-        })();
-        console.log(c);
-    }
-    expect: {
-        var c = "FAIL";
-        (function() {
-            var a = 0;
-            switch (a = { b: 0 }, a.b) {
-              case 0:
-                c = "PASS";
-            }
-        })();
-        console.log(c);
-    }
-    expect_stdout: "PASS"
-}
-
 issue_3389: {
     options = {
         evaluate: true,

test/compress/pure_funcs.js

@@ -136,7 +136,7 @@ relational: {
         side_effects :true,
     }
     input: {
-        foo() in foo();
+        foo() in new foo();
         foo() instanceof bar();
         foo() < "bar";
         bar() > foo();
@@ -680,3 +680,130 @@ issue_3325_2: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3858: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: "strict",
+        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 = {
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: "strict",
+        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 = {
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: "strict",
+        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 = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        keep_fargs: "strict",
+        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 = {
+        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",
+    ]
+}

test/compress/pure_getters.js

@@ -848,12 +848,11 @@ collapse_vars_1_true: {
     }
     expect: {
         function f(a, b) {
-            for (;;) {
+            for (;;)
                 if (a.g() || b.p) break;
         }
     }
 }
-}
 
 collapse_vars_1_false: {
     options = {

test/compress/sandbox.js

@@ -80,3 +80,21 @@ log_global: {
     }
     expect_stdout: "[object global]"
 }
+
+issue_4054: {
+    input: {
+        console.log({
+            set p(v) {
+                throw "FAIL";
+            },
+        });
+    }
+    expect: {
+        console.log({
+            set p(v) {
+                throw "FAIL";
+            },
+        });
+    }
+    expect_stdout: "{ p: [Setter] }"
+}

test/compress/sequences.js

@@ -877,7 +877,7 @@ for_init_var: {
     expect_stdout: "PASS"
 }
 
-forin: {
+forin_1: {
     options = {
         sequences: true,
     }
@@ -895,6 +895,49 @@ forin: {
     expect_stdout: "PASS"
 }
 
+forin_2: {
+    options = {
+        evaluate: true,
+        inline: true,
+        reduce_vars: true,
+        sequences: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            p: 1,
+            q: 2,
+        };
+        var k = "k";
+        for ((console.log("exp"), o)[function() {
+            console.log("prop");
+            return k;
+        }()] in function() {
+            console.log("obj");
+            return o;
+        }())
+            console.log(o.k, o[o.k]);
+    }
+    expect: {
+        var o = {
+            p: 1,
+            q: 2,
+        };
+        for ((console.log("exp"), o)[console.log("prop"), "k"] in console.log("obj"), o)
+            console.log(o.k, o[o.k]);
+    }
+    expect_stdout: [
+        "obj",
+        "exp",
+        "prop",
+        "p 1",
+        "exp",
+        "prop",
+        "q 2",
+    ]
+}
+
 call: {
     options = {
         sequences: true,
@@ -1112,3 +1155,25 @@ issue_3703: {
     }
     expect_stdout: "PASS"
 }
+
+issue_4079: {
+    options = {
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        try {
+            typeof (0, A);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            A;
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+}

test/compress/side_effects.js

@@ -97,9 +97,8 @@ issue_2233_2: {
         var RegExp;
         UndeclaredGlobal;
         function foo() {
-            var Number;
             AnotherUndeclaredGlobal;
-            Number.isNaN;
+            (void 0).isNaN;
         }
     }
 }
@@ -246,6 +245,31 @@ unsafe_builtin_2: {
     expect_stdout: "object PASS PASS"
 }
 
+unsafe_builtin_3: {
+    options = {
+        conditionals: true,
+        side_effects: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var o = {};
+        if (42 < Math.random())
+            o.p = "FAIL";
+        else
+            o.p = "PASS";
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {};
+        o.p = 42 < Math.random() ? "FAIL" : "PASS";
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: "p PASS"
+}
+
 unsafe_string_replace: {
     options = {
         side_effects: true,
@@ -275,3 +299,210 @@ drop_value: {
         foo(), bar();
     }
 }
+
+operator_in: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        try {
+            "foo" in true;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            0 in true;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3983_1: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        evaluate: true,
+        inline: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        function f() {
+            g && g();
+        }
+        f();
+        function g() {
+            0 ? a : 0;
+        }
+        var b = a;
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        g();
+        function g() {}
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3983_2: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        evaluate: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        function f() {
+            g && g();
+        }
+        f();
+        function g() {
+            0 ? a : 0;
+        }
+        var b = a;
+        console.log(a);
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4008: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "PASS";
+        function f(b, b) {
+            console.log(b);
+        }
+        f && f(a && a[a]);
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        function f(b, b) {
+            console.log(b);
+        }
+        f(a[a]);
+        console.log(a);
+    }
+    expect_stdout: [
+        "undefined",
+        "PASS",
+    ]
+}
+
+trim_new: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        new function(a) {
+            console.log(a);
+        }("PASS");
+    }
+    expect: {
+        (function(a) {
+            console.log(a);
+        })("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4325: {
+    options = {
+        keep_fargs: "strict",
+        passes: 2,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        (function f() {
+            (function(b, c) {
+                try {
+                    c.p = 0;
+                } catch (e) {
+                    console.log("PASS");
+                    return b;
+                }
+                c;
+            })(f++);
+        })();
+    }
+    expect: {
+        (function() {
+            (function() {
+                try {
+                    (void 0).p = 0;
+                } catch (e) {
+                    console.log("PASS");
+                    return;
+                }
+            })();
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4366_1: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        ({
+            p: 42,
+            get p() {},
+            q: console.log("PASS"),
+        });
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4366_2: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        ({
+            set p(v) {},
+            q: console.log("PASS"),
+            p: 42,
+        });
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}

test/compress/spread.js

@@ -0,0 +1,806 @@
+collapse_vars_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a;
+        [ ...a = "PASS", "PASS"].slice();
+        console.log(a);
+    }
+    expect: {
+        var a;
+        [ ...a = "PASS", "PASS"].slice();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+collapse_vars_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            a = "PASS";
+            [ ...42, "PASS"].slice();
+        } catch (e) {
+            console.log(a);
+        }
+    }
+    expect: {
+        var a = "FAIL";
+        try {
+            a = "PASS";
+            [ ...42, "PASS"].slice();
+        } catch (e) {
+            console.log(a);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+collapse_vars_3: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            [ ...(a = "PASS", 42), "PASS"].slice();
+        } catch (e) {
+            console.log(a);
+        }
+    }
+    expect: {
+        var a = "FAIL";
+        try {
+            [ ...(a = "PASS", 42), "PASS"].slice();
+        } catch (e) {
+            console.log(a);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+collapse_vars_4: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            return a;
+        }(...[ "PASS", "FAIL" ]));
+    }
+    expect: {
+        console.log(function(a) {
+            return a;
+        }(...[ "PASS", "FAIL" ]));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+dont_inline: {
+    options = {
+        inline: true,
+    }
+    input: {
+        console.log(function(a) {
+            return a;
+        }(...[ "PASS", "FAIL" ]));
+    }
+    expect: {
+        console.log(function(a) {
+            return a;
+        }(...[ "PASS", "FAIL" ]));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+do_inline: {
+    options = {
+        inline: true,
+        spread: true,
+    }
+    input: {
+        console.log(function(a) {
+            return a;
+        }(...[ "PASS", "FAIL" ]));
+    }
+    expect: {
+        console.log(("FAIL", "PASS"));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+drop_empty_call_1: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        try {
+            (function() {})(...null);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            [ ...null ];
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+drop_empty_call_2: {
+    options = {
+        side_effects: true,
+        spread: true,
+    }
+    input: {
+        (function() {})(...[ console.log("PASS") ]);
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+convert_hole: {
+    options = {
+        spread: true,
+    }
+    input: {
+        console.log(...[ "PASS", , 42 ]);
+    }
+    expect: {
+        console.log("PASS", void 0, 42);
+    }
+    expect_stdout: "PASS undefined 42"
+    node_version: ">=6"
+}
+
+keep_property_access: {
+    options = {
+        properties: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(function() {
+            return [ ..."foo" ][0];
+        }());
+    }
+    expect: {
+        console.log(function() {
+            return [ ..."foo" ][0];
+        }());
+    }
+    expect_stdout: "f"
+    node_version: ">=6"
+}
+
+keep_fargs: {
+    options = {
+        keep_fargs: "strict",
+        unused: true,
+    }
+    input: {
+        var a = [ "PASS" ];
+        (function(b, c) {
+            console.log(c);
+        })(console, ...a);
+    }
+    expect: {
+        var a = [ "PASS" ];
+        (function(b, c) {
+            console.log(c);
+        })(console, ...a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+reduce_vars_1: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(b, c) {
+            return c ? "PASS" : "FAIL";
+        }(..."foo"));
+    }
+    expect: {
+        console.log(function(b, c) {
+            return c ? "PASS" : "FAIL";
+        }(..."foo"));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+reduce_vars_2: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function(b, c) {
+            return c ? "PASS" : "FAIL";
+        }(..."foo"));
+    }
+    expect: {
+        console.log(function(b, c) {
+            return c ? "PASS" : "FAIL";
+        }(..."foo"));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+convert_setter: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        var o = {
+            ...{
+                set PASS(v) {},
+            },
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            PASS: void 0,
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: "PASS undefined"
+    node_version: ">=8"
+}
+
+keep_getter_1: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        ({
+            ...{
+                get p() {
+                    console.log("PASS");
+                },
+            },
+            get q() {
+                console.log("FAIL");
+            },
+        });
+    }
+    expect: {
+        ({
+            ...{
+                get p() {
+                    console.log("PASS");
+                },
+            },
+        });
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+keep_getter_2: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        ({
+            ...(console.log("foo"), {
+                get p() {
+                    console.log("bar");
+                },
+            }),
+        });
+    }
+    expect: {
+        ({
+            ...(console.log("foo"), {
+                get p() {
+                    console.log("bar");
+                },
+            }),
+        });
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=8"
+}
+
+keep_getter_3: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        ({
+            ...function() {
+                return {
+                    get p() {
+                        console.log("PASS");
+                    },
+                };
+            }(),
+        });
+    }
+    expect: {
+        ({
+            ...function() {
+                return {
+                    get p() {
+                        console.log("PASS");
+                    },
+                };
+            }(),
+        });
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+keep_getter_4: {
+    options = {
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var o = {
+            get p() {
+                console.log("PASS");
+            },
+        };
+        ({
+            q: o,
+            ...o,
+        });
+    }
+    expect: {
+        var o = {
+            get p() {
+                console.log("PASS");
+            },
+        };
+        ({
+            ...o,
+        });
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+keep_accessor: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        var o = {
+            ...{
+                get p() {
+                    console.log("GET");
+                    return this.r;
+                },
+                set q(v) {
+                    console.log("SET", v);
+                },
+                r: 42,
+            },
+            r: null,
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            ...{
+                get p() {
+                    console.log("GET");
+                    return this.r;
+                },
+                set q(v) {
+                    console.log("SET", v);
+                },
+                r: 42,
+            },
+            r: null,
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "GET",
+        "p 42",
+        "q undefined",
+        "r null",
+    ]
+    node_version: ">=8"
+}
+
+object_key_order_1: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        var o = {
+            ...{},
+            a: 1,
+            b: 2,
+            a: 3,
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            a: (1, 3),
+            b: 2,
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "a 3",
+        "b 2",
+    ]
+    node_version: ">=8 <=10"
+}
+
+object_key_order_2: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        var o = {
+            a: 1,
+            ...{},
+            b: 2,
+            a: 3,
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            a: (1, 3),
+            b: 2,
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "a 3",
+        "b 2",
+    ]
+    node_version: ">=8"
+}
+
+object_key_order_3: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        var o = {
+            a: 1,
+            b: 2,
+            ...{},
+            a: 3,
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            a: (1, 3),
+            b: 2,
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "a 3",
+        "b 2",
+    ]
+    node_version: ">=8"
+}
+
+object_key_order_4: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        var o = {
+            a: 1,
+            b: 2,
+            a: 3,
+            ...{},
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            a: (1, 3),
+            b: 2,
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "a 3",
+        "b 2",
+    ]
+    node_version: ">=8"
+}
+
+object_spread_array: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        var o = {
+            ...[ "foo", "bar" ],
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            ...[ "foo", "bar" ],
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "0 foo",
+        "1 bar",
+    ]
+    node_version: ">=8"
+}
+
+object_spread_string: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        var o = {
+            ..."foo",
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            ..."foo",
+        };
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "0 f",
+        "1 o",
+        "2 o",
+    ]
+    node_version: ">=8"
+}
+
+unused_var_side_effects: {
+    options = {
+        unused: true,
+    }
+    input: {
+        (function f(a) {
+            var b = {
+                ...a,
+            };
+        })({
+            get p() {
+                console.log("PASS");
+            },
+        });
+    }
+    expect: {
+        (function(a) {
+            ({
+                ...a,
+            });
+        })({
+            get p() {
+                console.log("PASS");
+            },
+        });
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+issue_4329: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        console.log({
+            ...{
+                get 0() {
+                    return "FAIL";
+                },
+                ...{
+                    0: "PASS",
+                },
+            },
+        }[0]);
+    }
+    expect: {
+        console.log({
+            ...{
+                get 0() {
+                    return "FAIL";
+                },
+                [0]: "PASS",
+            },
+        }[0]);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+issue_4331: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "PASS", b;
+        console,
+        b = a;
+        (function() {
+            a++;
+        })(...a);
+        console.log(b);
+    }
+    expect: {
+        var a = "PASS", b;
+        console;
+        (function() {
+            a++;
+        })(...b = a);
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_4342: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        try {
+            new function() {}(...42);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            [ ...42 ];
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_4345: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        console.log({
+            ...{
+                get 42() {
+                    return "FAIL";
+                },
+                ...{},
+                42: "PASS",
+            },
+        }[42]);
+    }
+    expect: {
+        console.log({
+            ...{
+                get 42() {
+                    return "FAIL";
+                },
+                [42]: "PASS",
+            },
+        }[42]);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+issue_4361: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            var a = console.log("foo");
+            console;
+            var b = {
+                ...a,
+            };
+        }());
+    }
+    expect: {
+        console.log(function() {
+            var a = console.log("foo");
+            console;
+            ({
+                ...a,
+            });
+        }());
+    }
+    expect_stdout: [
+        "foo",
+        "undefined",
+    ]
+    node_version: ">=8"
+}
+
+issue_4363: {
+    options = {
+        objects: true,
+        spread: true,
+    }
+    input: {
+        ({
+            ...{
+                set [console.log("PASS")](v) {},
+            },
+        });
+    }
+    expect: {
+        ({
+            [console.log("PASS")]: void 0,
+        });
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}

test/compress/switch.js

@@ -1,5 +1,6 @@
 constant_switch_1: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -19,6 +20,7 @@ constant_switch_1: {
 
 constant_switch_2: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -39,6 +41,7 @@ constant_switch_2: {
 
 constant_switch_3: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -60,6 +63,7 @@ constant_switch_3: {
 
 constant_switch_4: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -86,6 +90,7 @@ constant_switch_4: {
 
 constant_switch_5: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -120,6 +125,7 @@ constant_switch_5: {
 
 constant_switch_6: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -154,6 +160,7 @@ constant_switch_6: {
 
 constant_switch_7: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -197,6 +204,7 @@ constant_switch_7: {
 
 constant_switch_8: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -226,6 +234,7 @@ constant_switch_8: {
 
 constant_switch_9: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -315,6 +324,7 @@ keep_default: {
 
 issue_1663: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -551,6 +561,7 @@ issue_441_2: {
 
 issue_1674: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         side_effects: true,
@@ -876,6 +887,7 @@ beautify: {
 
 issue_1758: {
     options = {
+        conditionals: true,
         dead_code: true,
         switches: true,
     }
@@ -898,6 +910,7 @@ issue_1758: {
 
 issue_2535: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         switches: true,
@@ -919,6 +932,7 @@ issue_2535: {
 
 issue_1750: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         switches: true,
@@ -963,6 +977,7 @@ drop_switch_1: {
 
 drop_switch_2: {
     options = {
+        conditionals: true,
         dead_code: true,
         switches: true,
     }
@@ -1007,6 +1022,7 @@ drop_switch_3: {
 
 drop_switch_4: {
     options = {
+        conditionals: true,
         dead_code: true,
         switches: true,
     }
@@ -1028,3 +1044,140 @@ drop_switch_4: {
     }
     expect_stdout: "PASS"
 }
+
+drop_switch_5: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        switch (A) {
+          case B:
+            x();
+          default:
+        }
+        switch (C) {
+          default:
+            y();
+          case D:
+        }
+    }
+    expect: {
+        A === B && x();
+        C !== D && y();
+    }
+}
+
+drop_switch_6: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        switch (A) {
+          case B:
+          default:
+            x();
+        }
+        switch (C) {
+          default:
+          case D:
+            y();
+        }
+    }
+    expect: {
+        A === B;
+        x();
+        C !== D;
+        y();
+    }
+}
+
+drop_switch_7: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        switch (A) {
+          case B:
+            w();
+          default:
+            x();
+        }
+        switch (C) {
+          default:
+            y();
+          case D:
+            z();
+        }
+    }
+    expect: {
+        A === B && w();
+        x();
+        C !== D && y();
+        z();
+    }
+}
+
+drop_switch_8: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        switch (A) {
+          case B:
+            w();
+            break;
+          default:
+            x();
+        }
+        switch (C) {
+          default:
+            y();
+            break;
+          case D:
+            z();
+        }
+    }
+    expect: {
+        (A === B ? w : x)();
+        (C !== D ? y : z)();
+    }
+}
+
+issue_4059: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        switches: true,
+    }
+    input: {
+        switch (0) {
+          default:
+          case 1:
+            break;
+          case a:
+            break;
+            var a;
+        }
+        console.log("PASS");
+    }
+    expect: {
+        switch (0) {
+          default:
+            break;
+          case a:
+            break;
+            var a;
+        }
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}

test/compress/transform.js

@@ -69,6 +69,7 @@ label_if_break: {
         dead_code: true,
         evaluate: true,
         side_effects: true,
+        unused: true,
     }
     input: {
         L: if (true) {

test/compress/typeof.js

@@ -435,3 +435,25 @@ emberjs_global: {
     }
     expect_stdout: Error("PASS")
 }
+
+issue_3817: {
+    options = {
+        comparisons: true,
+        conditionals: true,
+        passes: 2,
+        typeofs: true,
+    }
+    input: {
+        if ("A" == typeof A || !console.log("PASS")) switch (false) {
+          case "undefined" == typeof A:
+            console.log("FAIL");
+        }
+    }
+    expect: {
+        if ("A" == typeof A || !console.log("PASS")) switch (false) {
+          case "undefined" == typeof A:
+            console.log("FAIL");
+        }
+    }
+    expect_stdout: "PASS"
+}

test/compress/unicode.js

@@ -1,3 +1,37 @@
+ascii_only_false: {
+    options = {}
+    beautify = {
+        ascii_only: false,
+    }
+    input: {
+        console.log(
+            "\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: 'console.log("\\x000\\x001\\x007\\x008\\0","\\0\x01\x02\x03\x04\x05\x06\x07\\b\\t\\n\\v\\f\\r\x0e\x0f","\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f",\' !"# ... }~\x7f\x80\x81 ... \xfe\xff\u0fff\uffff\');'
+    expect_stdout: true
+}
+
+ascii_only_true: {
+    options = {}
+    beautify = {
+        ascii_only: true,
+    }
+    input: {
+        console.log(
+            "\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: 'console.log("\\x000\\x001\\x007\\x008\\0","\\0\\x01\\x02\\x03\\x04\\x05\\x06\\x07\\b\\t\\n\\v\\f\\r\\x0e\\x0f","\\x10\\x11\\x12\\x13\\x14\\x15\\x16\\x17\\x18\\x19\\x1a\\x1b\\x1c\\x1d\\x1e\\x1f",\' !"# ... }~\\x7f\\x80\\x81 ... \\xfe\\xff\\u0fff\\uffff\');'
+    expect_stdout: true
+}
+
 unicode_parse_variables: {
     options = {}
     input: {
@@ -141,3 +175,35 @@ issue_2569: {
     }
     expect_exact: 'new RegExp("[\\udc42-\\udcaa\\udd74-\\udd96\\ude45-\\ude4f\\udea3-\\udecc]");'
 }
+
+surrogate_pair: {
+    beautify = {
+        ascii_only: false,
+    }
+    input: {
+        var \u{2f800} = {
+            \u{2f801}: "\u{100000}",
+        };
+        \u{2f800}.\u{2f802} = "\u{100001}";
+        console.log(typeof \u{2f800}, \u{2f800}.\u{2f801}, \u{2f800}["\u{2f802}"]);
+    }
+    expect_exact: 'var \ud87e\udc00={"\ud87e\udc01":"\udbc0\udc00"};\ud87e\udc00.\ud87e\udc02="\udbc0\udc01";console.log(typeof \ud87e\udc00,\ud87e\udc00.\ud87e\udc01,\ud87e\udc00["\ud87e\udc02"]);'
+    expect_stdout: "object \udbc0\udc00 \udbc0\udc01"
+    node_version: ">=4"
+}
+
+surrogate_pair_ascii: {
+    beautify = {
+        ascii_only: true,
+    }
+    input: {
+        var \u{2f800} = {
+            \u{2f801}: "\u{100000}",
+        };
+        \u{2f800}.\u{2f802} = "\u{100001}";
+        console.log(typeof \u{2f800}, \u{2f800}.\u{2f801}, \u{2f800}["\u{2f802}"]);
+    }
+    expect_exact: 'var \\u{2f800}={"\\ud87e\\udc01":"\\udbc0\\udc00"};\\u{2f800}.\\u{2f802}="\\udbc0\\udc01";console.log(typeof \\u{2f800},\\u{2f800}.\\u{2f801},\\u{2f800}["\\ud87e\\udc02"]);'
+    expect_stdout: "object \udbc0\udc00 \udbc0\udc01"
+    node_version: ">=4"
+}

test/compress/varify.js

@@ -0,0 +1,411 @@
+reduce_merge_const: {
+    options = {
+        merge_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        const a = console;
+        console.log(typeof a);
+        var b = typeof a;
+        console.log(b);
+    }
+    expect: {
+        var b = console;
+        console.log(typeof b);
+        b = typeof b;
+        console.log(b);
+    }
+    expect_stdout: [
+        "object",
+        "object",
+    ]
+}
+
+reduce_merge_let: {
+    options = {
+        merge_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        let a = console;
+        console.log(typeof a);
+        var b = typeof a;
+        console.log(b);
+    }
+    expect: {
+        "use strict";
+        var b = console;
+        console.log(typeof b);
+        b = typeof b;
+        console.log(b);
+    }
+    expect_stdout: [
+        "object",
+        "object",
+    ]
+    node_version: ">=4"
+}
+
+reduce_block_const: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        {
+            const a = typeof console;
+            console.log(a);
+        }
+    }
+    expect: {
+        var a = typeof console;
+        console.log(a);
+    }
+    expect_stdout: "object"
+}
+
+reduce_block_let: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        {
+            let a = typeof console;
+            console.log(a);
+        }
+    }
+    expect: {
+        "use strict";
+        var a = typeof console;
+        console.log(a);
+    }
+    expect_stdout: "object"
+    node_version: ">=4"
+}
+
+hoist_props_const: {
+    options = {
+        hoist_props: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        {
+            const o = {
+                p: "PASS",
+            };
+            console.log(o.p);
+        }
+    }
+    expect: {
+        var o_p = "PASS";
+        console.log(o_p);
+    }
+    expect_stdout: "PASS"
+}
+
+hoist_props_let: {
+    options = {
+        hoist_props: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        {
+            let o = {
+                p: "PASS",
+            };
+            console.log(o.p);
+        }
+    }
+    expect: {
+        "use strict";
+        var o_p = "PASS";
+        console.log(o_p);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+scope_adjustment_const: {
+    options = {
+        conditionals: true,
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        for (var k in [ 42 ])
+            console.log(function f() {
+                if (k) {
+                    const a = 0;
+                }
+            }());
+    }
+    expect: {
+        for (var k in [ 42 ])
+            console.log(void (k && 0));
+    }
+    expect_stdout: "undefined"
+}
+
+scope_adjustment_let: {
+    options = {
+        conditionals: true,
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        for (var k in [ 42 ])
+            console.log(function f() {
+                if (k) {
+                    let a = 0;
+                }
+            }());
+    }
+    expect: {
+        "use strict";
+        for (var k in [ 42 ])
+            console.log(void (k && 0));
+    }
+    expect_stdout: "undefined"
+    node_version: ">=4"
+}
+
+issue_4191_const: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        const a = function() {};
+        console.log(typeof a, a());
+    }
+    expect: {
+        function a() {};
+        console.log(typeof a, a());
+    }
+    expect_stdout: "function undefined"
+}
+
+issue_4191_let: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        let a = function() {};
+        console.log(typeof a, a());
+    }
+    expect: {
+        "use strict";
+        function a() {};
+        console.log(typeof a, a());
+    }
+    expect_stdout: "function undefined"
+    node_version: ">=4"
+}
+
+forin_const_1: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        const o = {
+            foo: 42,
+            bar: "PASS",
+        };
+        for (const k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            foo: 42,
+            bar: "PASS",
+        };
+        for (const k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: true
+    node_version: ">=4"
+}
+
+forin_const_2: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        const o = {
+            p: 42,
+            q: "PASS",
+        };
+        for (const [ k ] in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            p: 42,
+            q: "PASS",
+        }, k;
+        for ([ k ] in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "p 42",
+        "q PASS",
+    ]
+    node_version: ">=6"
+}
+
+forin_let_1: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        let o = {
+            foo: 42,
+            bar: "PASS",
+        };
+        for (let k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        "use strict";
+        var o = {
+            foo: 42,
+            bar: "PASS",
+        }, k;
+        for (k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "foo 42",
+        "bar PASS",
+    ]
+    node_version: ">=4"
+}
+
+forin_let_2: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        let o = {
+            p: 42,
+            q: "PASS",
+        };
+        for (let [ k ] in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {
+            p: 42,
+            q: "PASS",
+        }, k;
+        for ([ k ] in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "p 42",
+        "q PASS",
+    ]
+    node_version: ">=6"
+}
+
+issue_4290_1_const: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        const a = 0;
+        var a;
+    }
+    expect: {
+        const a = 0;
+        var a;
+    }
+    expect_stdout: true
+}
+
+issue_4290_1_let: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        let a = 0;
+        var a;
+    }
+    expect: {
+        "use strict";
+        let a = 0;
+        var a;
+    }
+    expect_stdout: true
+    node_version: ">=4"
+}
+
+drop_forin_let: {
+    options = {
+        loops: true,
+        toplevel: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        for (let a in console.log("PASS"));
+    }
+    expect: {
+        "use strict";
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}

test/input/invalid/switch.js

@@ -0,0 +1,4 @@
+switch (0) {
+  default:
+  default:
+}

test/input/issue-3040/expect.js

@@ -1,2 +1,41 @@
-function _toConsumableArray(arr){if(Array.isArray(arr)){for(var i=0,arr2=Array(arr.length);i<arr.length;i++){arr2[i]=arr[i]}return arr2}else{return Array.from(arr)}}var _require=require("bar"),foo=_require.foo;var _require2=require("world"),hello=_require2.hello;foo.x.apply(foo,_toConsumableArray(foo.y(hello.z)));
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbImlucHV0Mi5qcyJdLCJzb3VyY2VzQ29udGVudCI6WyJjb25zdCB7Zm9vfSA9IHJlcXVpcmUoXCJiYXJcIik7XG5jb25zdCB7aGVsbG99ID0gcmVxdWlyZShcIndvcmxkXCIpO1xuXG5mb28ueCguLi5mb28ueShoZWxsby56KSk7XG4iXSwibmFtZXMiOlsicmVxdWlyZSIsImFyciJdLCJtYXBwaW5ncyI6IjBKQUFjQSxLQUFRQyJ9
+"use strict";
+
+function _toConsumableArray(arr) {
+    return _arrayWithoutHoles(arr) || _iterableToArray(arr) || _unsupportedIterableToArray(arr) || _nonIterableSpread();
+}
+
+function _nonIterableSpread() {
+    throw new TypeError("Invalid attempt to spread non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method.");
+}
+
+function _unsupportedIterableToArray(o, minLen) {
+    if (!o) return;
+    if (typeof o === "string") return _arrayLikeToArray(o, minLen);
+    var n = Object.prototype.toString.call(o).slice(8, -1);
+    if (n === "Object" && o.constructor) n = o.constructor.name;
+    if (n === "Map" || n === "Set") return Array.from(n);
+    if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen);
+}
+
+function _iterableToArray(iter) {
+    if (typeof Symbol !== "undefined" && Symbol.iterator in Object(iter)) return Array.from(iter);
+}
+
+function _arrayWithoutHoles(arr) {
+    if (Array.isArray(arr)) return _arrayLikeToArray(arr);
+}
+
+function _arrayLikeToArray(arr, len) {
+    if (len == null || len > arr.length) len = arr.length;
+    for (var i = 0, arr2 = new Array(len); i < len; i++) {
+        arr2[i] = arr[i];
+    }
+    return arr2;
+}
+
+var _require = require("bar"), foo = _require.foo;
+
+var _require2 = require("world"), hello = _require2.hello;
+
+foo.x.apply(foo, _toConsumableArray(foo.y(hello.z)));
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,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

test/input/issue-3040/input.js

@@ -1,4 +1,16 @@
-function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
+"use strict";
+
+function _toConsumableArray(arr) { return _arrayWithoutHoles(arr) || _iterableToArray(arr) || _unsupportedIterableToArray(arr) || _nonIterableSpread(); }
+
+function _nonIterableSpread() { throw new TypeError("Invalid attempt to spread non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); }
+
+function _unsupportedIterableToArray(o, minLen) { if (!o) return; if (typeof o === "string") return _arrayLikeToArray(o, minLen); var n = Object.prototype.toString.call(o).slice(8, -1); if (n === "Object" && o.constructor) n = o.constructor.name; if (n === "Map" || n === "Set") return Array.from(n); if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen); }
+
+function _iterableToArray(iter) { if (typeof Symbol !== "undefined" && Symbol.iterator in Object(iter)) return Array.from(iter); }
+
+function _arrayWithoutHoles(arr) { if (Array.isArray(arr)) return _arrayLikeToArray(arr); }
+
+function _arrayLikeToArray(arr, len) { if (len == null || len > arr.length) len = arr.length; for (var i = 0, arr2 = new Array(len); i < len; i++) { arr2[i] = arr[i]; } return arr2; }
 
 var _require = require("bar"),
     foo = _require.foo;

test/input/issue-3040/input.js.map

@@ -1 +1,11 @@
-{"version":3,"sources":["input2.js"],"names":["require","foo","hello","x","apply","_toConsumableArray","y","z"],"mappings":"kLAAcA,QAAQ,OAAfC,aAAAA,kBACSD,QAAQ,SAAjBE,gBAAAA,MAEPD,IAAIE,EAAJC,MAAAH,IAAAI,mBAASJ,IAAIK,EAAEJ,MAAMK","sourcesContent":["const {foo} = require(\"bar\");\nconst {hello} = require(\"world\");\n\nfoo.x(...foo.y(hello.z));\n"]}
+{
+    "version": 3,
+    "sources": [
+        "input.js"
+    ],
+    "names": [],
+    "mappings": ";;;;;;;;;;;;;;eAAc,OAAO,CAAC,KAAD,C;IAAd,G,YAAA,G;;gBACS,OAAO,CAAC,OAAD,C;IAAhB,K,aAAA,K;;AAEP,GAAG,CAAC,CAAJ,OAAA,GAAG,qBAAM,GAAG,CAAC,CAAJ,CAAM,KAAK,CAAC,CAAZ,CAAN,EAAH",
+    "sourcesContent": [
+        "const {foo} = require(\"bar\");\nconst {hello} = require(\"world\");\n\nfoo.x(...foo.y(hello.z));\n"
+    ]
+}

test/input/issue-3294/output.js

@@ -1,2 +1,2 @@
-new function(){console.log(3)};
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUErQyxJQUFyQyxXQUFnQkEsUUFBUUMsSUFBSSJ9
+console.log(3);
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUEwQkEsUUFBUUMsSUFBSSJ9

test/input/issue-505/output.js

@@ -2,4 +2,4 @@ function test(a){
 "aaaaaaaaaaaaaaaa"
 ;a(err,data),a(err,
 data)}
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsidGVzdCIsImNhbGxiYWNrIiwiZXJyIiwiZGF0YSJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0EsS0FBS0M7QUFDVjtDQUNBQSxFQUFTQyxJQUFLQyxNQUNkRixFQUFTQztBQUFLQyJ9
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsidGVzdCIsImNhbGxiYWNrIiwiZXJyIiwiZGF0YSJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0EsS0FBS0M7O0NBRVZBLEVBQVNDLElBQUtDLE1BQ2RGLEVBQVNDO0FBQUtDIn0=

test/input/issue-520/output.js

@@ -1,2 +1,2 @@
-new function(){console.log(3)};
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUErQyxJQUFyQyxXQUFnQkEsUUFBUUMsSUFBSSJ9
+console.log(3);
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUEwQkEsUUFBUUMsSUFBSSJ9

test/input/reduce/diff_error.js

@@ -0,0 +1,5 @@
+(function f(a) {
+    do {
+        console.log(f.length);
+    } while (console.log(f += 0));
+})();

test/input/reduce/diff_error.reduced.js

@@ -0,0 +1,19 @@
+// (beautified)
+(function f(a) {
+    do {
+        console.log(f.length);
+    } while (console.log(f += 0));
+})();
+// output: 1
+// function(){}0
+// 
+// minify: 0
+// function(){}0
+// 
+// options: {
+//   "compress": {
+//     "keep_fargs": false,
+//     "unsafe": true
+//   },
+//   "mangle": false
+// }

test/input/reduce/label.js

@@ -1,9 +1,3 @@
-var o = this;
-
-for (var k in o) L17060: {
-    a++;
+UNUSED: {
+    console.log(0 - .1 - .1 - .1);
 }
-
-var a;
-
-console.log(k);

test/input/reduce/label.reduced.js

@@ -1,15 +1,12 @@
 // (beautified)
-var o = this;
-
-for (var k in o) {}
-
-var a;
-
-console.log(k);
-// output: a
+console.log(0 - 1 - .1 - .1);
+// output: -1.2000000000000002
 // 
-// minify: k
+// minify: -1.2
 // 
 // options: {
+//   "compress": {
+//     "unsafe_math": true
+//   },
 //   "mangle": false
 // }

test/jetstream.js

@@ -8,16 +8,15 @@ if (typeof phantom == "undefined") {
     require("../tools/exit");
     var args = process.argv.slice(2);
     var debug = args.indexOf("--debug");
-    if (debug >= 0) {
+    if (debug < 0) {
+        debug = false;
+    } else {
         args.splice(debug, 1);
         debug = true;
-    } else {
-        debug = false;
     }
-    if (!args.length) {
-        args.push("-mcb", "beautify=false,webkit");
-    }
-    args.push("--timings");
+    if (!args.length) args.push("-mcb", "beautify=false,webkit");
+    args.unshift("bin/uglifyjs");
+    args.push("--validate", "--timings");
     var child_process = require("child_process");
     var fetch = require("./fetch");
     var http = require("http");
@@ -39,10 +38,10 @@ if (typeof phantom == "undefined") {
                 });
                 if (/\.js$/.test(url)) {
                     var stderr = "";
-                    var uglifyjs = child_process.fork("bin/uglifyjs", args, {
+                    var uglifyjs = child_process.spawn(process.argv[0], args, {
                         silent: true
                     }).on("exit", function(code) {
-                        console.log("uglifyjs", url.slice(site.length + 1), args.join(" "));
+                        console.log("uglifyjs", url.slice(site.length + 1), args.slice(1).join(" "));
                         console.log(stderr);
                         if (code) throw new Error("uglifyjs failed with code " + code);
                     });
@@ -61,7 +60,7 @@ if (typeof phantom == "undefined") {
         var port = server.address().port;
         if (debug) {
             console.log("http://localhost:" + port + "/");
-        } else {
+        } else (function install() {
             child_process.spawn(process.platform == "win32" ? "npm.cmd" : "npm", [
                 "install",
                 "phantomjs-prebuilt@2.1.14",
@@ -72,7 +71,10 @@ if (typeof phantom == "undefined") {
             ], {
                 stdio: [ "ignore", 1, 2 ]
             }).on("exit", function(code) {
-                if (code) throw new Error("npm install failed!");
+                if (code) {
+                    console.log("npm install failed with code", code);
+                    return install();
+                }
                 var program = require("phantomjs-prebuilt").exec(process.argv[1], port);
                 program.stdout.pipe(process.stdout);
                 program.stderr.pipe(process.stderr);
@@ -83,7 +85,7 @@ if (typeof phantom == "undefined") {
                     process.exit(0);
                 });
             });
-        }
+        })();
     });
     server.timeout = 0;
 } else {

test/mocha/async.js

@@ -0,0 +1,65 @@
+var assert = require("assert");
+var UglifyJS = require("../node");
+
+describe("async", function() {
+    it("Should reject `await` as symbol name within async functions only", function() {
+        [
+            "function await() {}",
+            "function(await) {}",
+            "function() { await; }",
+            "function() { await:{} }",
+            "function() { var await; }",
+            "function() { function await() {} }",
+            "function() { try {} catch (await) {} }",
+        ].forEach(function(code) {
+            var ast = UglifyJS.parse("(" + code + ")();");
+            assert.strictEqual(ast.TYPE, "Toplevel");
+            assert.strictEqual(ast.body.length, 1);
+            assert.strictEqual(ast.body[0].TYPE, "SimpleStatement");
+            assert.strictEqual(ast.body[0].body.TYPE, "Call");
+            assert.strictEqual(ast.body[0].body.expression.TYPE, "Function");
+            assert.throws(function() {
+                UglifyJS.parse("(async " + code + ")();");
+            }, function(e) {
+                return e instanceof UglifyJS.JS_Parse_Error;
+            }, code);
+        });
+    });
+    it("Should reject `await` expression outside of async functions", function() {
+        [
+            "await 42;",
+            "function f() { await 42; }",
+            "async function f() { function g() { await 42; } }",
+        ].forEach(function(code) {
+            assert.throws(function() {
+                UglifyJS.parse(code);
+            }, function(e) {
+                return e instanceof UglifyJS.JS_Parse_Error;
+            }, code);
+        });
+    });
+    it("Should reject `await` expression directly on computed key of function argument", function() {
+        [
+            "function f({ [await 42]: a }) {}",
+            "async function f({ [await 42]: a }) {}",
+        ].forEach(function(code) {
+            assert.throws(function() {
+                UglifyJS.parse(code);
+            }, function(e) {
+                return e instanceof UglifyJS.JS_Parse_Error;
+            }, code);
+        });
+    });
+    it("Should accept `await` expression nested within computed key of function argument", function() {
+        [
+            "function f({ [async function() { await 42; }()]: a }) {}",
+            "async function f({ [async function() { await 42; }()]: a }) {}",
+        ].forEach(function(code) {
+            var ast = UglifyJS.parse(code);
+            assert.strictEqual(ast.TYPE, "Toplevel");
+            assert.strictEqual(ast.body.length, 1);
+            assert.strictEqual(ast.body[0].argnames.length, 1);
+            assert.strictEqual(ast.body[0].argnames[0].TYPE, "DestructuredObject");
+        });
+    });
+});

test/mocha/cli.js

@@ -2,6 +2,7 @@ var assert = require("assert");
 var exec = require("child_process").exec;
 var fs = require("fs");
 var run_code = require("../sandbox").run_code;
+var to_ascii = require("../node").to_ascii;
 
 function read(path) {
     return fs.readFileSync(path, "utf8");
@@ -48,6 +49,62 @@ describe("bin/uglifyjs", function() {
             done();
         });
     });
+    it("Should work with --source-map names=true", function(done) {
+        exec([
+            uglifyjscmd,
+            "--beautify",
+            "--source-map", [
+                "names=true",
+                "url=inline",
+            ].join(","),
+        ].join(" "), function(err, stdout) {
+            if (err) throw err;
+            var expected = [
+                "var obj = {",
+                "    p: a,",
+                "    q: b",
+                "};",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,",
+            ].join("\n")
+            assert.strictEqual(stdout.slice(0, expected.length), expected);
+            var map = JSON.parse(to_ascii(stdout.slice(expected.length).trim()));
+            assert.deepEqual(map.names, [ "obj", "p", "a", "q", "b" ]);
+            done();
+        }).stdin.end([
+            "var obj = {",
+            "    p: a,",
+            "    q: b",
+            "};",
+        ].join("\n"));
+    });
+    it("Should work with --source-map names=false", function(done) {
+        exec([
+            uglifyjscmd,
+            "--beautify",
+            "--source-map", [
+                "names=false",
+                "url=inline",
+            ].join(","),
+        ].join(" "), function(err, stdout) {
+            if (err) throw err;
+            var expected = [
+                "var obj = {",
+                "    p: a,",
+                "    q: b",
+                "};",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,",
+            ].join("\n")
+            assert.strictEqual(stdout.slice(0, expected.length), expected);
+            var map = JSON.parse(to_ascii(stdout.slice(expected.length).trim()));
+            assert.deepEqual(map.names, []);
+            done();
+        }).stdin.end([
+            "var obj = {",
+            "    p: a,",
+            "    q: b",
+            "};",
+        ].join("\n"));
+    });
     it("Should give sensible error against invalid input source map", function(done) {
         var command = uglifyjscmd + " test/mocha.js --source-map content=blah,url=inline --verbose";
         exec(command, function(err, stdout, stderr) {
@@ -109,9 +166,12 @@ describe("bin/uglifyjs", function() {
         }
         var command = [
             uglifyjscmd,
-            "--source-map", "content=" + mapFile,
-            "--source-map", "includeSources=true",
-            "--source-map", "url=inline",
+            "--beautify",
+            "--source-map", [
+                "content=" + mapFile,
+                "includeSources",
+                "url=inline",
+            ].join(","),
         ].join(" ");
 
         var child = exec(command, function(err, stdout) {
@@ -189,7 +249,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with `--output-opts`", function(done) {
-        var command = uglifyjscmd + ' test/input/issue-1482/input.js -O';
+        var command = uglifyjscmd + ' test/input/issue-1482/input.js -O ascii_only';
         exec(command, function(err, stdout) {
             if (err) throw err;
             assert.strictEqual(stdout, read("test/input/issue-1482/default.js"));
@@ -197,7 +257,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should fail when both --beautify & --output-opts are specified", function(done) {
-        var command = uglifyjscmd + " test/input/issue-520/input.js -bO";
+        var command = uglifyjscmd + " test/input/issue-520/input.js -bO ascii_only";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stderr, "ERROR: --beautify cannot be used with --output-opts\n");
@@ -270,7 +330,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should fail with invalid syntax", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/simple.js';
+        var command = uglifyjscmd + " test/input/invalid/simple.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             var lines = stderr.split(/\n/);
@@ -282,7 +342,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should fail with correct marking of tabs", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/tab.js';
+        var command = uglifyjscmd + " test/input/invalid/tab.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             var lines = stderr.split(/\n/);
@@ -294,7 +354,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should fail with correct marking at start of line", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/eof.js';
+        var command = uglifyjscmd + " test/input/invalid/eof.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             var lines = stderr.split(/\n/);
@@ -306,7 +366,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should fail with a missing loop body", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/loop-no-body.js';
+        var command = uglifyjscmd + " test/input/invalid/loop-no-body.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             var lines = stderr.split(/\n/);
@@ -318,7 +378,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (5--)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/assign_1.js';
+        var command = uglifyjscmd + " test/input/invalid/assign_1.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -332,7 +392,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (Math.random() /= 2)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/assign_2.js';
+        var command = uglifyjscmd + " test/input/invalid/assign_2.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -346,7 +406,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (++this)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/assign_3.js';
+        var command = uglifyjscmd + " test/input/invalid/assign_3.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -360,7 +420,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (++null)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/assign_4.js';
+        var command = uglifyjscmd + " test/input/invalid/assign_4.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -374,7 +434,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (a.=)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/dot_1.js';
+        var command = uglifyjscmd + " test/input/invalid/dot_1.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -388,7 +448,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (%.a)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/dot_2.js';
+        var command = uglifyjscmd + " test/input/invalid/dot_2.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -402,7 +462,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (a./();)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/dot_3.js';
+        var command = uglifyjscmd + " test/input/invalid/dot_3.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -416,7 +476,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error ({%: 1})", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/object.js';
+        var command = uglifyjscmd + " test/input/invalid/object.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -430,7 +490,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (delete x)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/delete.js';
+        var command = uglifyjscmd + " test/input/invalid/delete.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -444,7 +504,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (function g(arguments))", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/function_1.js';
+        var command = uglifyjscmd + " test/input/invalid/function_1.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -458,7 +518,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (function eval())", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/function_2.js';
+        var command = uglifyjscmd + " test/input/invalid/function_2.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -472,7 +532,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (iife arguments())", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/function_3.js';
+        var command = uglifyjscmd + " test/input/invalid/function_3.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -486,7 +546,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (catch (eval))", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/try.js';
+        var command = uglifyjscmd + " test/input/invalid/try.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -500,7 +560,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (var eval)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/var.js';
+        var command = uglifyjscmd + " test/input/invalid/var.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -514,7 +574,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (else)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/else.js';
+        var command = uglifyjscmd + " test/input/invalid/else.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -528,7 +588,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (return)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/return.js';
+        var command = uglifyjscmd + " test/input/invalid/return.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -542,7 +602,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (for-in init)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/for-in_1.js';
+        var command = uglifyjscmd + " test/input/invalid/for-in_1.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -556,7 +616,7 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (for-in var)", function(done) {
-        var command = uglifyjscmd + ' test/input/invalid/for-in_2.js';
+        var command = uglifyjscmd + " test/input/invalid/for-in_2.js";
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -569,6 +629,18 @@ describe("bin/uglifyjs", function() {
             done();
         });
     });
+    it("Should throw syntax error (switch defaults)", function(done) {
+        var command = uglifyjscmd + " test/input/invalid/switch.js";
+        exec(command, function(err, stdout, stderr) {
+            assert.ok(err);
+            var lines = stderr.split(/\n/);
+            assert.strictEqual(lines[0], "Parse error at test/input/invalid/switch.js:3,2");
+            assert.strictEqual(lines[1], "  default:");
+            assert.strictEqual(lines[2], "  ^");
+            assert.strictEqual(lines[3], "ERROR: More than one default clause in switch statement");
+            done();
+        });
+    });
     it("Should handle literal string as source map input", function(done) {
         var command = [
             uglifyjscmd,
@@ -657,7 +729,7 @@ describe("bin/uglifyjs", function() {
         var command = uglifyjscmd + " test/input/issue-3315/input.js --config-file test/input/issue-3315/config.json";
         exec(command, function(err, stdout) {
             if (err) throw err;
-            assert.strictEqual(stdout, 'function f(){"aaaaaaaaaa";var a={prop:1,a:2};return a.prop+a.a}\n');
+            assert.strictEqual(stdout, 'function f(){"aaaaaaaaaa";var a={prop:1,t:2};return a.prop+a.t}\n');
             done();
         });
     });

test/mocha/minify.js

@@ -1,7 +1,7 @@
 var assert = require("assert");
 var readFileSync = require("fs").readFileSync;
 var run_code = require("../sandbox").run_code;
-var UglifyJS = require("../../");
+var UglifyJS = require("../..");
 
 function read(path) {
     return readFileSync(path, "utf8");
@@ -9,18 +9,30 @@ function read(path) {
 
 describe("minify", function() {
     it("Should test basic sanity of minify with default options", function() {
-        var js = 'function foo(bar) { if (bar) return 3; else return 7; var u = not_called(); }';
+        var js = "function foo(bar) { if (bar) return 3; else return 7; var u = not_called(); }";
         var result = UglifyJS.minify(js);
-        assert.strictEqual(result.code, 'function foo(n){return n?3:7}');
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, "function foo(n){return n?3:7}");
     });
-
+    it("Should not mutate minify `options`", function() {
+        var options = {
+            compress: true,
+            mangle: false,
+            output: {},
+        };
+        var value = JSON.stringify(options);
+        var result = UglifyJS.minify("print(6 * 7);", options);
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, "print(42);");
+        assert.strictEqual(JSON.stringify(options), value);
+    })
     it("Should skip inherited keys from `files`", function() {
         var files = Object.create({ skip: this });
         files[0] = "alert(1 + 1)";
         var result = UglifyJS.minify(files);
+        if (result.error) throw result.error;
         assert.strictEqual(result.code, "alert(2);");
     });
-
     it("Should work with mangle.cache", function() {
         var cache = {};
         var original = "";
@@ -53,7 +65,6 @@ describe("minify", function() {
         ].join(""));
         assert.strictEqual(run_code(compressed, true), run_code(original, true));
     });
-
     it("Should work with nameCache", function() {
         var cache = {};
         var original = "";
@@ -86,7 +97,6 @@ describe("minify", function() {
         ].join(""));
         assert.strictEqual(run_code(compressed, true), run_code(original, true));
     });
-
     it("Should avoid cached names when mangling top-level variables", function() {
         var cache = {};
         var original = "";
@@ -115,7 +125,6 @@ describe("minify", function() {
         ].join(""));
         assert.strictEqual(run_code(compressed, true), run_code(original, true));
     });
-
     it("Should avoid cached names when mangling inner-scoped variables", function() {
         var cache = {};
         var original = "";
@@ -139,7 +148,6 @@ describe("minify", function() {
         ].join(""));
         assert.strictEqual(run_code(compressed, true), run_code(original, true));
     });
-
     it("Should not parse invalid use of reserved words", function() {
         assert.strictEqual(UglifyJS.minify("function enum(){}").error, undefined);
         assert.strictEqual(UglifyJS.minify("function static(){}").error, undefined);
@@ -155,7 +163,6 @@ describe("minify", function() {
                 }});
             assert.strictEqual(result.code, 'var foo={"x":1,y:2,"z":3};');
         });
-
         it("Should preserve quote styles when quote_style is 3", function() {
             var js = 'var foo = {"x": 1, y: 2, \'z\': 3};';
             var result = UglifyJS.minify(js, {
@@ -165,7 +172,6 @@ describe("minify", function() {
                 }});
             assert.strictEqual(result.code, 'var foo={"x":1,y:2,\'z\':3};');
         });
-
         it("Should not preserve quotes in object literals when disabled", function() {
             var js = 'var foo = {"x": 1, y: 2, \'z\': 3};';
             var result = UglifyJS.minify(js, {

test/mocha/number-literal.js

@@ -28,4 +28,65 @@ describe("Number literals", function() {
             assert.throws(test(inputs[i]), error, inputs[i]);
         }
     });
+    it("Should parse binary, hexadecimal, octal and underscore correctly", function() {
+        [
+            "42",
+            "4_2",
+            "052",
+            "0o52",
+            "0O52",
+            "0o5_2",
+            "0x2a",
+            "0X2A",
+            "0x2_a",
+            "0b101010",
+            "0B101010",
+            "0b101_010",
+            "0.0000000042e+10",
+            "0.0000000042E+10",
+            "0.0_000000042e+10",
+            "0.0000000042e+1_0",
+            "0.000_000_004_2e+1_0",
+            "0.000_000_004_2e+1_0-0B101_010+0x2_A-0o5_2+4_2",
+        ].forEach(function(code) {
+            var result = UglifyJS.minify(code, {
+                compress: {
+                    expression: true,
+                },
+            });
+            if (result.error) throw result.error;
+            assert.strictEqual(result.code, "42;");
+        });
+    });
+    it("Should reject invalid use of underscore", function() {
+        [
+            "_42",
+            "_+42",
+            "+_42",
+        ].forEach(function(code) {
+            var node = UglifyJS.parse(code, {
+                expression: true,
+            });
+            assert.ok(!node.is_constant(), code);
+            assert.ok(!(node instanceof UglifyJS.AST_Statement), code);
+        });
+        [
+            "42_",
+            "4__2",
+            "0_52",
+            "05_2",
+            "0_o52",
+            "0o_52",
+            "0.0000000042_e10",
+            "0.0000000042e_10",
+            "0.0000000042e_+10",
+            "0.0000000042e+_10",
+        ].forEach(function(code) {
+            assert.throws(function() {
+                UglifyJS.parse(code);
+            }, function(e) {
+                return e instanceof UglifyJS.JS_Parse_Error;
+            }, code);
+        });
+    });
 });

test/mocha/operator.js

@@ -486,4 +486,19 @@ describe("operator", function() {
             assert.strictEqual(UglifyJS.parse(exp[0]).print_to_string(), exp[1] + ";");
         });
     });
+    it("Should preserve space between /regex/ and `in`", function() {
+        [
+            "/regex/ in {}",
+            "/regex/g in {}",
+            "0 + /regex/ in {}",
+            "0 + /regex/g in {}",
+        ].forEach(function(exp) {
+            var code = UglifyJS.parse(exp).print_to_string();
+            try {
+                assert.strictEqual(UglifyJS.parse(code).print_to_string(), code);
+            } catch (ex) {
+                assert.fail("Failed to reparse: " + exp + "\n" + ex);
+            }
+        });
+    });
 });

test/mocha/reduce.js

@@ -24,6 +24,9 @@ describe("test/reduce.js", function() {
     });
     it("Should eliminate unreferenced labels", function() {
         var result = reduce_test(read("test/input/reduce/label.js"), {
+            compress: {
+                unsafe_math: true,
+            },
             mangle: false,
         }, {
             verbose: false,
@@ -186,7 +189,7 @@ describe("test/reduce.js", function() {
         ].join("\n"));
     });
     it("Should reduce infinite loops with reasonable performance", function() {
-        if (semver.satisfies(process.version, "0.10")) return;
+        if (semver.satisfies(process.version, "<=0.10")) return;
         this.timeout(120000);
         var result = reduce_test("while (/9/.test(1 - .8));", {
             compress: {
@@ -211,7 +214,7 @@ describe("test/reduce.js", function() {
     it("Should ignore difference in Error.message", function() {
         var result = reduce_test("null[function() {\n}];");
         if (result.error) throw result.error;
-        assert.strictEqual(result.code, (semver.satisfies(process.version, "0.10") ? [
+        assert.strictEqual(result.code, (semver.satisfies(process.version, "<=0.10") ? [
             "// Can't reproduce test failure",
             "// minify options: {}",
         ] : [
@@ -246,4 +249,68 @@ describe("test/reduce.js", function() {
             "// }",
         ].join("\n"));
     });
+    it("Should reduce test case which differs only in Error.message", function() {
+        var code = [
+            "var a=0;",
+            "try{",
+            "null[function(){}]",
+            "}catch(e){",
+            "for(var i in e.toString())",
+            "a++,console.log()",
+            "}",
+            "console.log(a);",
+        ].join("");
+        var result = reduce_test(code, {
+            compress: false,
+            mangle: false,
+            output: {
+                beautify: true,
+            },
+        });
+        if (result.error) throw result.error;
+        assert.deepEqual(result.warnings, []);
+        assert.strictEqual(result.code.replace(/function \(/g, "function("), (semver.satisfies(process.version, "<=0.10") ? [
+            "// Can't reproduce test failure",
+            "// minify options: {",
+            '//   "compress": false,',
+            '//   "mangle": false,',
+            '//   "output": {',
+            '//     "beautify": true',
+            "//   }",
+            "// }",
+        ] : [
+            [
+                "try{",
+                "null[function(){}]",
+                "}catch(e){",
+                "console.log(e)",
+                "}",
+            ].join(""),
+            "// output: TypeError: Cannot read property 'function(){}' of null",
+            "// ",
+            "// minify: TypeError: Cannot read property 'function() {}' of null",
+            "// ",
+            "// options: {",
+            '//   "compress": false,',
+            '//   "mangle": false,',
+            '//   "output": {',
+            '//     "beautify": true',
+            "//   }",
+            "// }",
+        ]).join("\n"));
+    });
+    it("Should handle corner cases when intermediate case differs only in Error.message", function() {
+        if (semver.satisfies(process.version, "<=0.10")) return;
+        var result = reduce_test(read("test/input/reduce/diff_error.js"), {
+            compress: {
+                keep_fargs: false,
+                unsafe: true,
+            },
+            mangle: false,
+        }, {
+            verbose: false,
+        });
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, read("test/input/reduce/diff_error.reduced.js"));
+    });
 });

test/mocha/sourcemaps.js

@@ -7,11 +7,13 @@ function read(path) {
 }
 
 function source_map(code) {
-    return JSON.parse(UglifyJS.minify(code, {
+    var result = UglifyJS.minify(code, {
         compress: false,
         mangle: false,
         sourceMap: true,
-    }).map);
+    });
+    if (result.error) throw result.error;
+    return JSON.parse(result.map);
 }
 
 function get_map() {
@@ -65,6 +67,40 @@ describe("sourcemaps", function() {
         ].join("\n"));
         assert.deepEqual(map.names, [ "enabled", "x" ]);
     });
+    it("Should work with sourceMap.names=true", function() {
+        var result = UglifyJS.minify([
+            "var obj = {",
+            "    p: a,",
+            "    q: b",
+            "};",
+        ].join("\n"), {
+            compress: false,
+            mangle: false,
+            sourceMap: {
+                names: true,
+            },
+        });
+        if (result.error) throw result.error;
+        var map = JSON.parse(result.map);
+        assert.deepEqual(map.names, [ "obj", "p", "a", "q", "b" ]);
+    });
+    it("Should work with sourceMap.names=false", function() {
+        var result = UglifyJS.minify([
+            "var obj = {",
+            "    p: a,",
+            "    q: b",
+            "};",
+        ].join("\n"), {
+            compress: false,
+            mangle: false,
+            sourceMap: {
+                names: false,
+            },
+        });
+        if (result.error) throw result.error;
+        var map = JSON.parse(result.map);
+        assert.deepEqual(map.names, []);
+    });
     it("Should mark array/object literals", function() {
         var result = UglifyJS.minify([
             "var obj = {};",
@@ -277,6 +313,12 @@ describe("sourcemaps", function() {
     });
 
     describe("input sourcemaps", function() {
+        it("Should not modify input source map", function() {
+            var orig = get_map();
+            var original = JSON.stringify(orig);
+            var map = prepare_map(orig);
+            assert.strictEqual(JSON.stringify(orig), original);
+        });
         it("Should copy over original sourcesContent", function() {
             var orig = get_map();
             var map = prepare_map(orig);

test/mocha/string-literal.js

@@ -1,64 +1,58 @@
 var assert = require("assert");
+var run_code = require("../sandbox").run_code;
 var UglifyJS = require("../node");
 
 describe("String literals", function() {
     it("Should throw syntax error if a string literal contains a newline", function() {
-        var inputs = [
+        [
             "'\n'",
             "'\r'",
             '"\r\n"',
             "'\u2028'",
-            '"\u2029"'
-        ];
-
-        var test = function(input) {
-            return function() {
+            '"\u2029"',
+        ].forEach(function(input) {
+            assert.throws(function() {
                 var ast = UglifyJS.parse(input);
-            };
-        };
-
-        var error = function(e) {
+            }, function(e) {
                 return e instanceof UglifyJS.JS_Parse_Error
                     && e.message === "Unterminated string constant";
-        };
-
-        for (var input in inputs) {
-            assert.throws(test(inputs[input]), error);
-        }
             });
-
+        });
+    });
+    it("Should handle line continuation correctly", function() {
+        [
+            '"\\\r"',
+            '"\\\n"',
+            '"\\\r\n"',
+        ].forEach(function(str) {
+            var code = "console.log(" + str + ");";
+            var result = UglifyJS.minify(code);
+            if (result.error) throw result.error;
+            assert.strictEqual(run_code(result.code), run_code(code));
+        });
+    });
     it("Should not throw syntax error if a string has a line continuation", function() {
-        var output = UglifyJS.parse('var a = "a\\\nb";').print_to_string();
-        assert.equal(output, 'var a="ab";');
+        var ast = UglifyJS.parse('var a = "a\\\nb";');
+        assert.equal(ast.print_to_string(), 'var a="ab";');
     });
-
     it("Should throw error in strict mode if string contains escaped octalIntegerLiteral", function() {
-        var inputs = [
+        [
             '"use strict";\n"\\76";',
             '"use strict";\nvar foo = "\\76";',
             '"use strict";\n"\\1";',
             '"use strict";\n"\\07";',
-            '"use strict";\n"\\011"'
-        ];
-
-        var test = function(input) {
-            return function() {
+            '"use strict";\n"\\011"',
+        ].forEach(function(input) {
+            assert.throws(function() {
                 var output = UglifyJS.parse(input);
-            }
-        };
-
-        var error = function(e) {
+            }, function(e) {
                 return e instanceof UglifyJS.JS_Parse_Error
                     && e.message === "Legacy octal escape sequences are not allowed in strict mode";
-        }
-
-        for (var input in inputs) {
-            assert.throws(test(inputs[input]), error);
-        }
             });
-
+        });
+    });
     it("Should not throw error outside strict mode if string contains escaped octalIntegerLiteral", function() {
-        var tests = [
+        [
             [ ';"\\76";', ';">";' ],
             [ ';"\\0";', ';"\\0";' ],
             [ ';"\\08"', ';"\\x008";' ],
@@ -66,19 +60,15 @@ describe("String literals", function() {
             [ ';"\\0008"', ';"\\x008";' ],
             [ ';"use\\\n strict";\n"\\07";', ';"use strict";"\07";' ],
             [ '"use strict" === "use strict";\n"\\76";', '"use strict"==="use strict";">";' ],
-        ];
-
-        for (var test in tests) {
-            var output = UglifyJS.parse(tests[test][0]).print_to_string();
-            assert.equal(output, tests[test][1]);
-        }
+        ].forEach(function(test) {
+            var ast = UglifyJS.parse(test[0]);
+            assert.equal(ast.print_to_string(), test[1]);
+        });
     });
-
     it("Should not throw error when digit is 8 or 9", function() {
         assert.equal(UglifyJS.parse('"use strict";;"\\08"').print_to_string(), '"use strict";;"\\x008";');
         assert.equal(UglifyJS.parse('"use strict";;"\\09"').print_to_string(), '"use strict";;"\\x009";');
     });
-
     it("Should not unescape unpaired surrogates", function() {
         var code = [];
         for (var i = 0; i <= 0xF; i++) {
@@ -115,4 +105,33 @@ describe("String literals", function() {
         assert.ok(code.length > ascii.code.length);
         assert.strictEqual(eval(code), eval(ascii.code));
     });
+    it("Should reject invalid Unicode escape sequence", function() {
+        [
+            'var foo = "\\u-111"',
+            'var bar = "\\u{-1}"',
+            'var baz = "\\ugggg"',
+        ].forEach(function(test) {
+            assert.throws(function() {
+                UglifyJS.parse(test);
+            }, function(e) {
+                return e instanceof UglifyJS.JS_Parse_Error
+                    && e.message === "Invalid hex-character pattern in string";
+            });
+        });
+    });
+    it("Should reject invalid code points in Unicode escape sequence", function() {
+        [
+            // A bit over the valid range
+            '"\\u{110000}"',
+            // 32-bit overflow resulting in "a"
+            '"\\u{100000061}"',
+        ].forEach(function(test) {
+            assert.throws(function() {
+                UglifyJS.parse(test);
+            }, function(e) {
+                return e instanceof UglifyJS.JS_Parse_Error
+                    && /^Invalid character code: /.test(e.message);
+            });
+        });
+    });
 });

test/mocha/tokens.js

@@ -5,7 +5,7 @@ describe("tokens", function() {
     it("Should give correct positions for accessors", function() {
         // location               0         1         2         3         4
         //                        01234567890123456789012345678901234567890123456789
-        var ast = UglifyJS.parse("var obj = { get latest() { return undefined; } }");
+        var ast = UglifyJS.parse("var obj = { get [prop]() { return undefined; } }");
         // test all AST_ObjectProperty tokens are set as expected
         var found = false;
         ast.walk(new UglifyJS.TreeWalker(function(node) {
@@ -13,9 +13,9 @@ describe("tokens", function() {
                 found = true;
                 assert.equal(node.start.pos, 12);
                 assert.equal(node.end.endpos, 46);
-                assert(node.key instanceof UglifyJS.AST_SymbolAccessor);
-                assert.equal(node.key.start.pos, 16);
-                assert.equal(node.key.end.endpos, 22);
+                assert(node.key instanceof UglifyJS.AST_SymbolRef);
+                assert.equal(node.key.start.pos, 17);
+                assert.equal(node.key.end.endpos, 21);
                 assert(node.value instanceof UglifyJS.AST_Accessor);
                 assert.equal(node.value.start.pos, 22);
                 assert.equal(node.value.end.endpos, 46);

test/mocha/with.js

@@ -17,7 +17,7 @@ describe("With", function() {
         var ast = UglifyJS.parse("with(e) {f(1, 2)}");
         ast.figure_out_scope();
         assert.equal(ast.uses_with, true);
-        assert.equal(ast.body[0].expression.scope.uses_with, true);
-        assert.equal(ast.body[0].body.body[0].body.expression.scope.uses_with, true);
+        assert.equal(ast.body[0].expression.scope.resolve().uses_with, true);
+        assert.equal(ast.body[0].body.body[0].body.expression.scope.resolve().uses_with, true);
     });
 });

test/mozilla-ast.js

@@ -24,11 +24,22 @@ function try_beautify(code) {
     }
 }
 
-function test(original, estree, description) {
-    var transformed = UglifyJS.minify(UglifyJS.AST_Node.from_mozilla_ast(estree), {
+function validate(ast) {
+    try {
+        ast.walk(new UglifyJS.TreeWalker(function(node) {
+            node.validate();
+        }));
+    } catch (e) {
+        return { error: e };
+    }
+    return UglifyJS.minify(ast, {
         compress: false,
-        mangle: false
+        mangle: false,
     });
+}
+
+function test(original, estree, description) {
+    var transformed = validate(UglifyJS.AST_Node.from_mozilla_ast(estree));
     if (transformed.error || original !== transformed.code) {
         console.log("//=============================================================");
         console.log("// !!!!!! Failed... round", round);

test/reduce.js

@@ -1,37 +1,54 @@
 var crypto = require("crypto");
-var U = require("./node");
+var U = require("..");
 var List = U.List;
 var os = require("os");
 var sandbox = require("./sandbox");
 
-// Reduce a ufuzz-style `console.log` based test case by iteratively replacing
-// AST nodes with various permutations. Each AST_Statement in the tree is also
-// speculatively dropped to determine whether it is needed.  If the altered
-// tree and the last known good tree produce the same non-nil error-free output
-// after being run, then the permutation survives to the next generation and
-// is the basis for subsequent iterations.  The test case is reduced as a
-// consequence of complex expressions being replaced with simpler ones.
-// This function assumes that the testcase will not result in a parse or
-// runtime Error.  Note that a reduced test case will have different runtime
-// output - it is not functionally equivalent to the original. The only criteria
-// is that once the generated reduced test case is run without minification, it
-// will produce different output from the code minified with `minify_options`.
-// Returns a `minify` result object with an additonal boolean property `reduced`.
+// Reduce a test case by iteratively replacing AST nodes with various
+// permutations. Each AST_Statement in the tree is also speculatively dropped
+// to determine whether it is needed.  If the altered tree and the last known
+// good tree produce the same output after being run, then the permutation
+// survives to the next generation and is the basis for subsequent iterations.
+// The test case is reduced as a consequence of complex expressions being
+// replaced with simpler ones.  Note that a reduced test case will have
+// different runtime output - it is not functionally equivalent to the
+// original. The only criteria is that once the generated reduced test case is
+// run without minification, it will produce different output from the code
+// minified with `minify_options`.  Returns a `minify` result object.
 
+Error.stackTraceLimit = Infinity;
 module.exports = function reduce_test(testcase, minify_options, reduce_options) {
-    if (testcase instanceof U.AST_Node) testcase = testcase.print_to_string();
     minify_options = minify_options || {};
     reduce_options = reduce_options || {};
+    var print_options = {};
+    [
+        "ie8",
+        "v8",
+        "webkit",
+    ].forEach(function(name) {
+        var value = minify_options[name] || minify_options.output && minify_options.output[name];
+        if (value) print_options[name] = value;
+    });
+    if (testcase instanceof U.AST_Node) testcase = testcase.print_to_string(print_options);
     var max_iterations = reduce_options.max_iterations || 1000;
     var max_timeout = reduce_options.max_timeout || 10000;
+    var warnings = [];
+    var log = reduce_options.log || function(msg) {
+        warnings.push(msg);
+    };
     var verbose = reduce_options.verbose;
     var minify_options_json = JSON.stringify(minify_options, null, 2);
     var result_cache = Object.create(null);
+    var test_for_diff = compare_run_code;
     // the initial timeout to assess the viability of the test case must be large
-    var differs = producesDifferentResultWhenMinified(result_cache, testcase, minify_options, max_timeout);
+    var differs = test_for_diff(testcase, minify_options, result_cache, max_timeout);
 
     if (verbose) {
-        console.error("// Node.js " + process.version + " on " + os.platform() + " " + os.arch());
+        log("// Node.js " + process.version + " on " + os.platform() + " " + os.arch());
+    }
+    if (differs.error && [ "DefaultsError", "SyntaxError" ].indexOf(differs.error.name) < 0) {
+        test_for_diff = test_minify;
+        differs = test_for_diff(testcase, minify_options, result_cache, max_timeout);
     }
     if (!differs) {
         // same stdout result produced when minified
@@ -39,16 +56,19 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             code: [
                 "// Can't reproduce test failure",
                 "// minify options: " + to_comment(minify_options_json)
-            ].join("\n")
+            ].join("\n"),
+            warnings: warnings,
         };
     } else if (differs.timed_out) {
         return {
             code: [
                 "// Can't reproduce test failure within " + max_timeout + "ms",
                 "// minify options: " + to_comment(minify_options_json)
-            ].join("\n")
+            ].join("\n"),
+            warnings: warnings,
         };
     } else if (differs.error) {
+        differs.warnings = warnings;
         return differs;
     } else if (is_error(differs.unminified_result)
         && is_error(differs.minified_result)
@@ -57,7 +77,8 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             code: [
                 "// No differences except in error message",
                 "// minify options: " + to_comment(minify_options_json)
-            ].join("\n")
+            ].join("\n"),
+            warnings: warnings,
         };
     } else {
         max_timeout = Math.min(100 * differs.elapsed, max_timeout);
@@ -83,6 +104,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
 
             // quick ignores
             if (node instanceof U.AST_Accessor) return;
+            if (node instanceof U.AST_Destructured) return;
             if (node instanceof U.AST_Directive) return;
             if (!in_list && node instanceof U.AST_EmptyStatement) return;
             if (node instanceof U.AST_Label) return;
@@ -100,19 +122,20 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             // no structural AST changes before this point.
             if (node.start._permute >= REPLACEMENTS.length) return;
 
-            if (parent instanceof U.AST_Assign
-                    && parent.left === node
-                || parent instanceof U.AST_Unary
-                    && parent.expression === node
-                    && ["++", "--", "delete"].indexOf(parent.operator) >= 0) {
             // ignore lvalues
+            if (parent instanceof U.AST_Assign && parent.left === node) return;
+            if (parent instanceof U.AST_DestructuredArray) return;
+            if (parent instanceof U.AST_DestructuredKeyVal && parent.value === node) return;
+            if (parent instanceof U.AST_Unary && parent.expression === node) switch (parent.operator) {
+              case "++":
+              case "--":
+              case "delete":
                 return;
             }
-            if ((parent instanceof U.AST_For || parent instanceof U.AST_ForIn)
-                && parent.init === node && node instanceof U.AST_Var) {
-                // preserve for (var ...)
-                return node;
-            }
+            // preserve for (var xxx; ...)
+            if (parent instanceof U.AST_For && parent.init === node && node instanceof U.AST_Definitions) return node;
+            // preserve for (xxx in ...)
+            if (parent instanceof U.AST_ForIn && parent.init === node) return node;
 
             // node specific permutations with no parent logic
 
@@ -121,47 +144,22 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 if (expr && !(expr instanceof U.AST_Hole)) {
                     node.start._permute++;
                     CHANGED = true;
-                    return expr;
+                    return expr instanceof U.AST_Spread ? expr.expression : expr;
                 }
             }
             else if (node instanceof U.AST_Binary) {
-                CHANGED = true;
                 var permute = ((node.start._permute += step) * steps | 0) % 4;
                 var expr = [
                     node.left,
                     node.right,
                 ][ permute & 1 ];
-                if (permute < 2) return expr;
-                // wrap with console.log()
-                return new U.AST_Call({
-                    expression: new U.AST_Dot({
-                        expression: new U.AST_SymbolRef({
-                            name: "console",
-                            start: {},
-                        }),
-                        property: "log",
-                        start: {},
-                    }),
-                    args: [ expr ],
-                    start: {},
-                });
-            }
-            else if (node instanceof U.AST_Catch || node instanceof U.AST_Finally) {
-                // drop catch or finally block
-                node.start._permute++;
                 CHANGED = true;
-                return null;
-            }
-            else if (node instanceof U.AST_Conditional) {
-                CHANGED = true;
-                return [
-                    node.condition,
-                    node.consequent,
-                    node.alternative,
-                ][ ((node.start._permute += step) * steps | 0) % 3 ];
+                return permute < 2 ? expr : wrap_with_console_log(expr);
             }
             else if (node instanceof U.AST_BlockStatement) {
-                if (in_list) {
+                if (in_list && node.body.filter(function(node) {
+                    return node instanceof U.AST_Const;
+                }).length == 0) {
                     node.start._permute++;
                     CHANGED = true;
                     return List.splice(node.body);
@@ -175,7 +173,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 ][ ((node.start._permute += step) * steps | 0) % 3 ];
                 if (expr) {
                     CHANGED = true;
-                    return expr;
+                    return expr instanceof U.AST_Spread ? expr.expression : expr;
                 }
                 if (node.expression instanceof U.AST_Function) {
                     // hoist and return expressions from the IIFE function expression
@@ -193,12 +191,26 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     return to_sequence(seq);
                 }
             }
+            else if (node instanceof U.AST_Catch) {
+                // drop catch block
+                node.start._permute++;
+                CHANGED = true;
+                return null;
+            }
+            else if (node instanceof U.AST_Conditional) {
+                CHANGED = true;
+                return [
+                    node.condition,
+                    node.consequent,
+                    node.alternative,
+                ][ ((node.start._permute += step) * steps | 0) % 3 ];
+            }
             else if (node instanceof U.AST_Defun) {
                 switch (((node.start._permute += step) * steps | 0) % 2) {
                   case 0:
                     CHANGED = true;
                     return List.skip;
-                  case 1:
+                  default:
                     if (!has_exit(node)) {
                         // hoist function declaration body
                         var body = node.body;
@@ -230,15 +242,11 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     return to_statement(expr);
                 }
             }
-            else if (node instanceof U.AST_PropAccess) {
-                var expr = [
-                    node.expression,
-                    node.property instanceof U.AST_Node && node.property,
-                ][ node.start._permute++ % 2 ];
-                if (expr) {
+            else if (node instanceof U.AST_Finally) {
+                // drop finally block
+                node.start._permute++;
                 CHANGED = true;
-                    return expr;
-                }
+                return null;
             }
             else if (node instanceof U.AST_For) {
                 var expr = [
@@ -254,13 +262,23 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 }
             }
             else if (node instanceof U.AST_ForIn) {
-                var expr = [
-                    node.init,
-                    node.object,
-                    node.body,
-                ][ (node.start._permute * steps | 0) % 3 ];
+                var expr;
+                switch ((node.start._permute * steps | 0) % 3) {
+                  case 0:
+                    if (!(node.init instanceof U.AST_Definitions
+                        && node.init.definitions[0].name instanceof U.AST_Destructured)) {
+                        expr = node.init;
+                    }
+                    break;
+                  case 1:
+                    expr = node.object;
+                    break;
+                  case 2:
+                    if (!has_loopcontrol(node.body, node, parent)) expr = node.body;
+                    break;
+                }
                 node.start._permute += step;
-                if (expr && (expr !== node.body || !has_loopcontrol(expr, node, parent))) {
+                if (expr) {
                     CHANGED = true;
                     return to_statement(expr);
                 }
@@ -287,6 +305,16 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     return expr;
                 }
             }
+            else if (node instanceof U.AST_PropAccess) {
+                var expr = [
+                    node.expression,
+                    node.property instanceof U.AST_Node && node.property,
+                ][ node.start._permute++ % 2 ];
+                if (expr) {
+                    CHANGED = true;
+                    return expr;
+                }
+            }
             else if (node instanceof U.AST_SimpleStatement) {
                 if (node.body instanceof U.AST_Call && node.body.expression instanceof U.AST_Function) {
                     // hoist simple statement IIFE function expression body
@@ -362,9 +390,8 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             }
 
             if (in_list) {
-                // special case to drop object properties and switch branches
-                if (parent instanceof U.AST_Object
-                    || parent instanceof U.AST_Switch && parent.expression != node) {
+                // drop switch branches
+                if (parent instanceof U.AST_Switch && parent.expression != node) {
                     node.start._permute++;
                     CHANGED = true;
                     return List.skip;
@@ -383,6 +410,15 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     CHANGED = true;
                     return List.skip;
                 }
+
+                // skip element/property from (destructured) array/object
+                if (parent instanceof U.AST_Array
+                    || parent instanceof U.AST_Destructured
+                    || parent instanceof U.AST_Object) {
+                    node.start._permute++;
+                    CHANGED = true;
+                    return List.skip;
+                }
             }
 
             // replace this node
@@ -406,7 +442,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     start: {},
                 });
             }
-            else if (node instanceof U.AST_Var) {
+            else if (node instanceof U.AST_Definitions) {
                 // remove empty var statement
                 if (node.definitions.length == 0) return in_list ? List.skip : new U.AST_EmptyStatement({
                     start: {},
@@ -414,34 +450,58 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             }
         });
 
+        var diff_error_message;
         for (var pass = 1; pass <= 3; ++pass) {
             var testcase_ast = U.parse(testcase);
+            if (diff_error_message === testcase) {
+                // only difference detected is in error message, so expose that and try again
+                testcase_ast.transform(new U.TreeTransformer(function(node, descend) {
+                    if (node.TYPE == "Call" && node.expression.print_to_string() == "console.log") {
+                        return to_sequence(node.args);
+                    }
+                    if (node instanceof U.AST_Catch && node.argname) {
+                        descend(node, this);
+                        node.body.unshift(new U.AST_SimpleStatement({
+                            body: wrap_with_console_log(new U.AST_SymbolRef(node.argname)),
+                            start: {},
+                        }));
+                        return node;
+                    }
+                }));
+                var code = testcase_ast.print_to_string(print_options);
+                var diff = test_for_diff(code, minify_options, result_cache, max_timeout);
+                if (diff && !diff.timed_out && !diff.error) {
+                    testcase = code;
+                    differs = diff;
+                } else {
+                    testcase_ast = U.parse(testcase);
+                }
+            }
+            diff_error_message = null;
             testcase_ast.walk(new U.TreeWalker(function(node) {
                 // unshare start props to retain visit data between iterations
                 node.start = JSON.parse(JSON.stringify(node.start));
                 node.start._permute = 0;
             }));
+            var before_iterations = testcase;
             for (var c = 0; c < max_iterations; ++c) {
-                if (verbose) {
-                    if (pass == 1 && c % 25 == 0) {
-                        console.error("// reduce test pass "
-                            + pass + ", iteration " + c + ": " + testcase.length + " bytes");
-                    }
+                if (verbose && pass == 1 && c % 25 == 0) {
+                    log("// reduce test pass " + pass + ", iteration " + c + ": " + testcase.length + " bytes");
                 }
                 var CHANGED = false;
                 var code_ast = testcase_ast.clone(true).transform(tt);
                 if (!CHANGED) break;
                 try {
-                    var code = code_ast.print_to_string();
+                    var code = code_ast.print_to_string(print_options);
                 } catch (ex) {
                     // AST is not well formed.
                     // no harm done - just log the error, ignore latest change and continue iterating.
-                    console.error("*** Error generating code from AST.");
-                    console.error(ex);
-                    console.error("*** Discarding permutation and continuing.");
+                    log("*** Error generating code from AST.");
+                    log(ex.stack);
+                    log("*** Discarding permutation and continuing.");
                     continue;
                 }
-                var diff = producesDifferentResultWhenMinified(result_cache, code, minify_options, max_timeout);
+                var diff = test_for_diff(code, minify_options, result_cache, max_timeout);
                 if (diff) {
                     if (diff.timed_out) {
                         // can't trust the validity of `code_ast` and `code` when timed out.
@@ -449,14 +509,15 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     } else if (diff.error) {
                         // something went wrong during minify() - could be malformed AST or genuine bug.
                         // no harm done - just log code & error, ignore latest change and continue iterating.
-                        console.error("*** Error during minification.");
-                        console.error(code);
-                        console.error(diff.error);
-                        console.error("*** Discarding permutation and continuing.");
+                        log("*** Error during minification.");
+                        log(code);
+                        log(diff.error.stack);
+                        log("*** Discarding permutation and continuing.");
                     } else if (is_error(diff.unminified_result)
                         && is_error(diff.minified_result)
                         && diff.unminified_result.name == diff.minified_result.name) {
                         // ignore difference in error messages caused by minification
+                        diff_error_message = testcase;
                     } else {
                         // latest permutation is valid, so use it as the basis of new changes
                         testcase_ast = code_ast;
@@ -465,13 +526,37 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     }
                 }
             }
-            if (c == 0) break;
+            if (before_iterations === testcase) break;
             if (verbose) {
-                console.error("// reduce test pass " + pass + ": " + testcase.length + " bytes");
+                log("// reduce test pass " + pass + ": " + testcase.length + " bytes");
+            }
+        }
+        var beautified = U.minify(testcase, {
+            compress: false,
+            mangle: false,
+            output: function() {
+                var options = JSON.parse(JSON.stringify(print_options));
+                options.beautify = true;
+                options.braces = true;
+                options.comments = true;
+                return options;
+            }(),
+        });
+        testcase = {
+            code: testcase,
+        };
+        if (!beautified.error) {
+            diff = test_for_diff(beautified.code, minify_options, result_cache, max_timeout);
+            if (diff && !diff.timed_out && !diff.error) {
+                testcase = beautified;
+                testcase.code = "// (beautified)\n" + testcase.code;
+                differs = diff;
             }
         }
-        testcase = try_beautify(result_cache, testcase, minify_options, differs.unminified_result, max_timeout);
         var lines = [ "" ];
+        if (isNaN(max_timeout)) {
+            lines.push("// minify error: " + to_comment(strip_color_codes(differs.minified_result.stack)));
+        } else {
             var unminified_result = strip_color_codes(differs.unminified_result);
             var minified_result = strip_color_codes(differs.minified_result);
             if (trim_trailing_whitespace(unminified_result) == trim_trailing_whitespace(minified_result)) {
@@ -486,8 +571,10 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     "// minify: " + to_comment(minified_result)
                 );
             }
+        }
         lines.push("// options: " + to_comment(minify_options_json));
         testcase.code += lines.join("\n");
+        testcase.warnings = warnings;
         return testcase;
     }
 };
@@ -504,28 +591,6 @@ function trim_trailing_whitespace(value) {
     return ("" + value).replace(/\s+$/, "");
 }
 
-function try_beautify(result_cache, testcase, minify_options, expected, timeout) {
-    var result = U.minify(testcase, {
-        compress: false,
-        mangle: false,
-        output: {
-            beautify: true,
-            braces: true,
-            comments: true,
-        },
-    });
-    if (result.error) return {
-        code: testcase,
-    };
-    var toplevel = sandbox.has_toplevel(minify_options);
-    var actual = run_code(result_cache, result.code, toplevel, timeout);
-    if (!sandbox.same_stdout(expected, actual)) return {
-        code: testcase,
-    };
-    result.code = "// (beautified)\n" + result.code;
-    return result;
-}
-
 function has_exit(fn) {
     var found = false;
     var tw = new U.TreeWalker(function(node) {
@@ -560,11 +625,11 @@ function is_error(result) {
 }
 
 function is_timed_out(result) {
-    return is_error(result) && /timed out/.test(result);
+    return is_error(result) && /timed out/.test(result.message);
 }
 
 function is_statement(node) {
-    return node instanceof U.AST_Statement && !(node instanceof U.AST_Function);
+    return node instanceof U.AST_Statement && !(node instanceof U.AST_AsyncFunction || node instanceof U.AST_Function);
 }
 
 function merge_sequence(array, node) {
@@ -592,31 +657,59 @@ function to_statement(node) {
     });
 }
 
-function run_code(result_cache, code, toplevel, timeout) {
-    var key = crypto.createHash("sha1").update(code).digest("base64");
-    return result_cache[key] || (result_cache[key] = sandbox.run_code(code, toplevel, timeout));
+function wrap_with_console_log(node) {
+    // wrap with console.log()
+    return new U.AST_Call({
+        expression: new U.AST_Dot({
+            expression: new U.AST_SymbolRef({
+                name: "console",
+                start: {},
+            }),
+            property: "log",
+            start: {},
+        }),
+        args: [ node ],
+        start: {},
+    });
 }
 
-function producesDifferentResultWhenMinified(result_cache, code, minify_options, max_timeout) {
+function run_code(code, toplevel, result_cache, timeout) {
+    var key = crypto.createHash("sha1").update(code).digest("base64");
+    var value = result_cache[key];
+    if (!value) {
+        var start = Date.now();
+        result_cache[key] = value = {
+            result: sandbox.run_code(code, toplevel, timeout),
+            elapsed: Date.now() - start,
+        };
+    }
+    return value;
+}
+
+function compare_run_code(code, minify_options, result_cache, max_timeout) {
     var minified = U.minify(code, minify_options);
     if (minified.error) return minified;
 
     var toplevel = sandbox.has_toplevel(minify_options);
-    var elapsed = Date.now();
-    var unminified_result = run_code(result_cache, code, toplevel, max_timeout);
-    elapsed = Date.now() - elapsed;
-    var timeout = Math.min(100 * elapsed, max_timeout);
-    var minified_result = run_code(result_cache, minified.code, toplevel, timeout);
+    var unminified = run_code(code, toplevel, result_cache, max_timeout);
+    var timeout = Math.min(100 * unminified.elapsed, max_timeout);
+    var minified_result = run_code(minified.code, toplevel, result_cache, timeout).result;
 
-    if (sandbox.same_stdout(unminified_result, minified_result)) {
-        return is_timed_out(unminified_result) && is_timed_out(minified_result) && {
+    if (sandbox.same_stdout(unminified.result, minified_result)) {
+        return is_timed_out(unminified.result) && is_timed_out(minified_result) && {
             timed_out: true,
         };
     }
     return {
-        unminified_result: unminified_result,
+        unminified_result: unminified.result,
         minified_result: minified_result,
-        elapsed: elapsed,
+        elapsed: unminified.elapsed,
+    };
+}
+
+function test_minify(code, minify_options) {
+    var minified = U.minify(code, minify_options);
+    return minified.error && {
+        minified_result: minified.error,
     };
 }
-Error.stackTraceLimit = Infinity;

test/release/benchmark.js

@@ -1,6 +1,3 @@
-setInterval(function() {
-    process.stderr.write("\0");
-}, 8 * 60 * 1000).unref();
 require("./run")([
     "-b",
     "-b braces",
@@ -12,6 +9,6 @@ require("./run")([
     "-mc keep_fargs=false,passes=3,pure_getters,unsafe,unsafe_comps,unsafe_math,unsafe_proto",
 ].map(function(options) {
     var args = options.split(/ /);
-    args.unshift("test/benchmark.js");
+    args.unshift("test/benchmark.js", "--validate");
     return args;
 }));

test/sandbox.js

@@ -26,10 +26,19 @@ var setupContext = new vm.Script([
 ]).join("\n"));
 
 function createContext() {
-    var ctx = vm.createContext(Object.defineProperty({}, "console", { value: { log: log } }));
+    var ctx = vm.createContext(Object.defineProperties({}, {
+        console: { value: { log: log } },
+        global: { get: self },
+        self: { get: self },
+        window: { get: self },
+    }));
     var global = setupContext.runInContext(ctx);
     return ctx;
 
+    function self() {
+        return this;
+    }
+
     function safe_log(arg, level) {
         if (arg) switch (typeof arg) {
           case "function":
@@ -37,10 +46,11 @@ function createContext() {
           case "object":
             if (arg === global) return "[object global]";
             if (/Error$/.test(arg.name)) return arg.toString();
+            if (typeof arg.then == "function") return "[object Promise]";
             arg.constructor.toString();
             if (level--) for (var key in arg) {
                 var desc = Object.getOwnPropertyDescriptor(arg, key);
-                if (!desc || !desc.get) arg[key] = safe_log(arg[key], level);
+                if (!desc || !desc.get && !desc.set) arg[key] = safe_log(arg[key], level);
             }
         }
         return arg;

test/ufuzz/actions.js

@@ -0,0 +1,67 @@
+var get = require("https").get;
+var parse = require("url").parse;
+
+var base, token, run_number, eldest = true;
+exports.init = function(url, auth, num) {
+    base = url;
+    token = auth;
+    run_number = num;
+};
+exports.should_stop = function(callback) {
+    read(base + "/actions/runs?per_page=100", function(reply) {
+        if (!reply || !Array.isArray(reply.workflow_runs)) return;
+        var runs = reply.workflow_runs.filter(function(workflow) {
+            return workflow.status != "completed";
+        }).sort(function(a, b) {
+            return b.run_number - a.run_number;
+        });
+        var found = false, remaining = 20;
+        (function next() {
+            if (!runs.length) return;
+            var workflow = runs.pop();
+            if (workflow.event == "schedule" && workflow.run_number == run_number) found = true;
+            read(workflow.jobs_url, function(reply) {
+                if (!reply || !Array.isArray(reply.jobs)) return;
+                if (!reply.jobs.every(function(job) {
+                    if (job.status == "completed") return true;
+                    remaining--;
+                    return found || workflow.event != "schedule";
+                })) return;
+                if (remaining >= 0) {
+                    next();
+                } else {
+                    callback();
+                }
+            });
+        })();
+    });
+};
+
+function read(url, callback) {
+    var done = function(reply) {
+        done = function() {};
+        callback(reply);
+    };
+    var options = parse(url);
+    options.headers = {
+        "Authorization": "Token " + token,
+        "User-Agent": "UglifyJS",
+    };
+    get(options, function(response) {
+        var chunks = [];
+        response.setEncoding("utf8");
+        response.on("data", function(chunk) {
+            chunks.push(chunk);
+        }).on("end", function() {
+            var reply;
+            try {
+                reply = JSON.parse(chunks.join(""))
+            } catch (e) {}
+            done(reply);
+        }).on("error", function() {
+            done();
+        });
+    }).on("error", function() {
+        done();
+    });
+}

test/ufuzz/job.js

@@ -1,39 +1,71 @@
+var actions = require("./actions");
 var child_process = require("child_process");
 
-var ping = 5 * 60 * 1000;
-var period = +process.argv[2];
-var endTime = Date.now() + period;
-for (var i = 0; i < 2; i++) spawn(endTime);
-
-function spawn(endTime) {
-    var child = child_process.spawn("node", [
+var args = [
     "--max-old-space-size=2048",
-        "test/ufuzz"
-    ], {
+    "test/ufuzz",
+];
+var iterations;
+switch (process.argv.length) {
+  case 3:
+    iterations = +process.argv[2];
+    args.push(iterations);
+    break;
+  case 5:
+    actions.init(process.argv[2], process.argv[3], +process.argv[4]);
+    break;
+  default:
+    throw new Error("invalid parameters");
+}
+var tasks = [ run(), run() ];
+if (iterations) return;
+var alive = setInterval(function() {
+    actions.should_stop(function() {
+        clearInterval(alive);
+        tasks.forEach(function(kill) {
+            kill();
+        });
+    });
+}, 8 * 60 * 1000);
+
+function run() {
+    var child, stdout, stderr, log;
+    spawn();
+    return function() {
+        clearInterval(log);
+        child.removeListener("exit", respawn);
+        child.kill();
+    };
+
+    function spawn() {
+        child = child_process.spawn("node", args, {
             stdio: [ "ignore", "pipe", "pipe" ]
         }).on("exit", respawn);
-    var stdout = "";
+        stdout = "";
         child.stdout.on("data", function(data) {
             stdout += data;
         });
-    var stderr = "";
+        stderr = "";
         child.stderr.on("data", trap).pipe(process.stdout);
-    var keepAlive = setInterval(function() {
+        log = setInterval(function() {
+            stdout = stdout.replace(/[^\r\n]+\r(?=[^\r\n]+\r)/g, "");
             var end = stdout.lastIndexOf("\r");
-        console.log(stdout.slice(stdout.lastIndexOf("\r", end - 1) + 1, end));
+            if (end < 0) return;
+            console.log(stdout.slice(0, end));
             stdout = stdout.slice(end + 1);
-    }, ping);
-    var timer = setTimeout(function() {
-        clearInterval(keepAlive);
-        child.removeListener("exit", respawn);
-        child.kill();
-    }, endTime - Date.now());
+        }, 5 * 60 * 1000);
+    }
 
     function respawn() {
         console.log(stdout.replace(/[^\r\n]*\r/g, ""));
-        clearInterval(keepAlive);
-        clearTimeout(timer);
-        spawn(endTime);
+        clearInterval(log);
+        if (!iterations) {
+            spawn();
+        } else if (process.exitCode) {
+            tasks.forEach(function(kill) {
+                kill();
+            });
+        }
     }
 
     function trap(data) {

tools/domprops.html

@@ -0,0 +1,456 @@
+<!doctype html>
+<html>
+<body>
+    <script>
+        !function(G) {
+            var domprops = [];
+            var objs = [ G ];
+            var tagNames = [
+                "a",
+                "abbr",
+                "acronym",
+                "address",
+                "applet",
+                "area",
+                "article",
+                "aside",
+                "audio",
+                "b",
+                "base",
+                "basefont",
+                "bdi",
+                "bdo",
+                "bgsound",
+                "big",
+                "blink",
+                "blockquote",
+                "body",
+                "br",
+                "button",
+                "canvas",
+                "caption",
+                "center",
+                "checked",
+                "cite",
+                "code",
+                "col",
+                "colgroup",
+                "command",
+                "comment",
+                "compact",
+                "content",
+                "data",
+                "datalist",
+                "dd",
+                "declare",
+                "defer",
+                "del",
+                "details",
+                "dfn",
+                "dialog",
+                "dir",
+                "disabled",
+                "div",
+                "dl",
+                "dt",
+                "element",
+                "em",
+                "embed",
+                "fieldset",
+                "figcaption",
+                "figure",
+                "font",
+                "footer",
+                "form",
+                "frame",
+                "frameset",
+                "h1",
+                "h2",
+                "h3",
+                "h4",
+                "h5",
+                "h6",
+                "head",
+                "header",
+                "hgroup",
+                "hr",
+                "html",
+                "i",
+                "iframe",
+                "image",
+                "img",
+                "input",
+                "ins",
+                "isindex",
+                "ismap",
+                "kbd",
+                "keygen",
+                "label",
+                "legend",
+                "li",
+                "link",
+                "listing",
+                "main",
+                "map",
+                "mark",
+                "marquee",
+                "math",
+                "menu",
+                "menuitem",
+                "meta",
+                "meter",
+                "multicol",
+                "multiple",
+                "nav",
+                "nextid",
+                "nobr",
+                "noembed",
+                "noframes",
+                "nohref",
+                "noresize",
+                "noscript",
+                "noshade",
+                "nowrap",
+                "object",
+                "ol",
+                "optgroup",
+                "option",
+                "output",
+                "p",
+                "param",
+                "picture",
+                "plaintext",
+                "pre",
+                "progress",
+                "q",
+                "rb",
+                "readonly",
+                "rp",
+                "rt",
+                "rtc",
+                "ruby",
+                "s",
+                "samp",
+                "script",
+                "section",
+                "select",
+                "selected",
+                "shadow",
+                "slot",
+                "small",
+                "source",
+                "spacer",
+                "span",
+                "strike",
+                "strong",
+                "style",
+                "sub",
+                "summary",
+                "sup",
+                "svg",
+                "table",
+                "tbody",
+                "td",
+                "template",
+                "textarea",
+                "tfoot",
+                "th",
+                "thead",
+                "time",
+                "title",
+                "tr",
+                "track",
+                "tt",
+                "u",
+                "ul",
+                "var",
+                "video",
+                "wbr",
+                "xmp",
+                "XXX",
+            ];
+            for (var n = 0; n < tagNames.length; n++) {
+                add(document.createElement(tagNames[n]));
+            }
+            var nsNames = {
+                "http://www.w3.org/1998/Math/MathML": [
+                    "annotation",
+                    "annotation-xml",
+                    "maction",
+                    "maligngroup",
+                    "malignmark",
+                    "math",
+                    "menclose",
+                    "merror",
+                    "mfenced",
+                    "mfrac",
+                    "mglyph",
+                    "mi",
+                    "mlabeledtr",
+                    "mlongdiv",
+                    "mmultiscripts",
+                    "mn",
+                    "mo",
+                    "mover",
+                    "mpadded",
+                    "mphantom",
+                    "mprescripts",
+                    "mroot",
+                    "mrow",
+                    "ms",
+                    "mscarries",
+                    "mscarry",
+                    "msgroup",
+                    "msline",
+                    "mspace",
+                    "msqrt",
+                    "msrow",
+                    "mstack",
+                    "mstyle",
+                    "msub",
+                    "msubsup",
+                    "msup",
+                    "mtable",
+                    "mtd",
+                    "mtext",
+                    "mtr",
+                    "munder",
+                    "munderover",
+                    "none",
+                    "semantics",
+                ],
+                "http://www.w3.org/2000/svg": [
+                    "a",
+                    "altGlyph",
+                    "altGlyphDef",
+                    "altGlyphItem",
+                    "animate",
+                    "animateColor",
+                    "animateMotion",
+                    "animateTransform",
+                    "circle",
+                    "clipPath",
+                    "color-profile",
+                    "cursor",
+                    "defs",
+                    "desc",
+                    "discard",
+                    "ellipse",
+                    "feBlend",
+                    "feColorMatrix",
+                    "feComponentTransfer",
+                    "feComposite",
+                    "feConvolveMatrix",
+                    "feDiffuseLighting",
+                    "feDisplacementMap",
+                    "feDistantLight",
+                    "feDropShadow",
+                    "feFlood",
+                    "feFuncA",
+                    "feFuncB",
+                    "feFuncG",
+                    "feFuncR",
+                    "feGaussianBlur",
+                    "feImage",
+                    "feMerge",
+                    "feMergeNode",
+                    "feMorphology",
+                    "feOffset",
+                    "fePointLight",
+                    "feSpecularLighting",
+                    "feSpotLight",
+                    "feTile",
+                    "feTurbulence",
+                    "filter",
+                    "font",
+                    "font-face",
+                    "font-face-format",
+                    "font-face-name",
+                    "font-face-src",
+                    "font-face-uri",
+                    "foreignObject",
+                    "g",
+                    "glyph",
+                    "glyphRef",
+                    "hatch",
+                    "hatchpath",
+                    "hkern",
+                    "image",
+                    "line",
+                    "linearGradient",
+                    "marker",
+                    "mask",
+                    "mesh",
+                    "meshgradient",
+                    "meshpatch",
+                    "meshrow",
+                    "metadata",
+                    "missing-glyph",
+                    "mpath",
+                    "path",
+                    "pattern",
+                    "polygon",
+                    "polyline",
+                    "radialGradient",
+                    "rect",
+                    "script",
+                    "set",
+                    "solidcolor",
+                    "stop",
+                    "style",
+                    "svg",
+                    "switch",
+                    "symbol",
+                    "text",
+                    "textPath",
+                    "title",
+                    "tref",
+                    "tspan",
+                    "unknown",
+                    "use",
+                    "view",
+                    "vkern",
+                ],
+            };
+            if (document.createElementNS) for (var ns in nsNames) {
+                for (var n = 0; n < nsNames[ns].length; n++) {
+                    add(document.createElementNS(ns, nsNames[ns][n]));
+                }
+            }
+            var skips = [
+                G.alert,
+                G.back,
+                G.blur,
+                G.captureEvents,
+                G.clearImmediate,
+                G.clearInterval,
+                G.clearTimeout,
+                G.close,
+                G.confirm,
+                G.console,
+                G.dump,
+                G.fetch,
+                G.find,
+                G.focus,
+                G.forward,
+                G.getAttention,
+                G.history,
+                G.home,
+                G.location,
+                G.moveBy,
+                G.moveTo,
+                G.navigator,
+                G.open,
+                G.openDialog,
+                G.print,
+                G.process,
+                G.prompt,
+                G.resizeBy,
+                G.resizeTo,
+                G.setImmediate,
+                G.setInterval,
+                G.setTimeout,
+                G.showModalDialog,
+                G.sizeToContent,
+                G.stop,
+            ];
+            var types = [];
+            var interfaces = [
+                "beforeunloadevent",
+                "compositionevent",
+                "customevent",
+                "devicemotionevent",
+                "deviceorientationevent",
+                "dragevent",
+                "event",
+                "events",
+                "focusevent",
+                "hashchangeevent",
+                "htmlevents",
+                "keyboardevent",
+                "messageevent",
+                "mouseevent",
+                "mouseevents",
+                "storageevent",
+                "svgevents",
+                "textevent",
+                "touchevent",
+                "uievent",
+                "uievents",
+            ];
+            var i = 0, full = false;
+            var addEvent = document.createEvent ? function(type) {
+                if (~indexOf(types, type)) return;
+                types.push(type);
+                for (var j = 0; j < interfaces.length; j++) try {
+                    var event = document.createEvent(interfaces[j]);
+                    event.initEvent(type, true, true);
+                    add(event);
+                } catch (e) {}
+            } : function() {};
+            var scanProperties = Object.getOwnPropertyNames ? function(o, fn) {
+                var names = Object.getOwnPropertyNames(o);
+                names.forEach(fn);
+                for (var k in o) if (!~indexOf(names, k)) fn(k);
+            } : function(o, fn) {
+                for (var k in o) fn(k);
+            };
+            setTimeout(function next() {
+                for (var j = 10; --j >= 0 && i < objs.length; i++) {
+                    var o = objs[i];
+                    var skip = ~indexOf(skips, o);
+                    try {
+                        scanProperties(o, function(k) {
+                            if (!~indexOf(domprops, k)) domprops.push(k);
+                            if (/^on/.test(k)) addEvent(k.slice(2));
+                            if (!full) try {
+                                add(o[k]);
+                            } catch (e) {}
+                        });
+                    } catch (e) {}
+                    if (skip || full) continue;
+                    try {
+                        add(o.__proto__);
+                    } catch (e) {}
+                    try {
+                        add(o.prototype);
+                    } catch (e) {}
+                    try {
+                        add(new o());
+                    } catch (e) {}
+                    try {
+                        add(o());
+                    } catch (e) {}
+                }
+                if (!full && objs.length > 20000) {
+                    alert(objs.length);
+                    full = true;
+                }
+                if (i < objs.length) {
+                    setTimeout(next, 0);
+                } else {
+                    document.write('<pre>[\n    "' + domprops.sort().join('",\n    "').replace(/&/g, "&amp;").replace(/</g, "&lt;") + '"\n]</pre>');
+                }
+            }, 0);
+
+            function add(o) {
+                if (o) switch (typeof o) {
+                case "function":
+                case "object":
+                    if (!~indexOf(objs, o)) objs.push(o);
+                }
+            }
+
+            function indexOf(list, value) {
+                var j = list.length;
+                while (--j >= 0) {
+                    if (list[j] === value) break;
+                }
+                return j;
+            }
+        }(function() {
+            return this;
+        }());
+    </script>
+</body>
+</html>

tools/exit.js

@@ -5,7 +5,7 @@ process.exit = function() {
     process.once("uncaughtException", function() {
         (function callback() {
             if (process.stdout.bufferSize || process.stderr.bufferSize) {
-                setImmediate(callback);
+                setTimeout(callback, 1);
             } else {
                 exit.apply(process, args);
             }

tools/node.js

@@ -66,8 +66,8 @@ function infer_options(options) {
 }
 
 exports.default_options = function() {
-    var defs = {};
-    Object.keys(infer_options({ 0: 0 })).forEach(function(component) {
+    var defs = infer_options({ 0: 0 });
+    Object.keys(defs).forEach(function(component) {
         var options = {};
         options[component] = { 0: 0 };
         if (options = infer_options(options)) {

tools/props.html

@@ -1,540 +0,0 @@
-<!doctype html>
-<html>
-<body>
-    <script>
-        !function() {
-            var names = [];
-            var scanned = [];
-            var to_scan = [];
-
-            function scan(obj) {
-                if (obj && typeof obj == "object" && !~scanned.indexOf(obj)) {
-                    scanned.push(obj);
-                    to_scan.push(obj);
-                }
-            }
-
-            scan(self);
-            [
-                "a",
-                "abbr",
-                "acronym",
-                "address",
-                "applet",
-                "area",
-                "article",
-                "aside",
-                "audio",
-                "b",
-                "base",
-                "basefont",
-                "bdi",
-                "bdo",
-                "bgsound",
-                "big",
-                "blink",
-                "blockquote",
-                "body",
-                "br",
-                "button",
-                "canvas",
-                "caption",
-                "center",
-                "checked",
-                "cite",
-                "code",
-                "col",
-                "colgroup",
-                "command",
-                "comment",
-                "compact",
-                "content",
-                "data",
-                "datalist",
-                "dd",
-                "declare",
-                "defer",
-                "del",
-                "details",
-                "dfn",
-                "dialog",
-                "dir",
-                "disabled",
-                "div",
-                "dl",
-                "dt",
-                "element",
-                "em",
-                "embed",
-                "fieldset",
-                "figcaption",
-                "figure",
-                "font",
-                "footer",
-                "form",
-                "frame",
-                "frameset",
-                "h1",
-                "h2",
-                "h3",
-                "h4",
-                "h5",
-                "h6",
-                "head",
-                "header",
-                "hgroup",
-                "hr",
-                "html",
-                "i",
-                "iframe",
-                "image",
-                "img",
-                "input",
-                "ins",
-                "isindex",
-                "ismap",
-                "kbd",
-                "keygen",
-                "label",
-                "legend",
-                "li",
-                "link",
-                "listing",
-                "main",
-                "map",
-                "mark",
-                "marquee",
-                "math",
-                "menu",
-                "menuitem",
-                "meta",
-                "meter",
-                "multicol",
-                "multiple",
-                "nav",
-                "nobr",
-                "noembed",
-                "noframes",
-                "nohref",
-                "noresize",
-                "noscript",
-                "noshade",
-                "nowrap",
-                "object",
-                "ol",
-                "optgroup",
-                "option",
-                "output",
-                "p",
-                "param",
-                "picture",
-                "plaintext",
-                "pre",
-                "progress",
-                "q",
-                "rb",
-                "readonly",
-                "rp",
-                "rt",
-                "rtc",
-                "ruby",
-                "s",
-                "samp",
-                "script",
-                "section",
-                "select",
-                "selected",
-                "shadow",
-                "small",
-                "source",
-                "spacer",
-                "span",
-                "strike",
-                "strong",
-                "style",
-                "sub",
-                "summary",
-                "sup",
-                "svg",
-                "table",
-                "tbody",
-                "td",
-                "template",
-                "textarea",
-                "tfoot",
-                "th",
-                "thead",
-                "time",
-                "title",
-                "tr",
-                "track",
-                "tt",
-                "u",
-                "ul",
-                "var",
-                "video",
-                "wbr",
-                "xmp",
-                "XXX",
-            ].forEach(function(tag) {
-                scan(document.createElement(tag));
-            });
-            [
-                "abort",
-                "absolutedeviceorientation",
-                "activate",
-                "active",
-                "addsourcebuffer",
-                "addstream",
-                "addtrack",
-                "afterprint",
-                "afterscriptexecute",
-                "afterupdate",
-                "animationcancel",
-                "animationend",
-                "animationiteration",
-                "animationstart",
-                "appinstalled",
-                "audioend",
-                "audioprocess",
-                "audiostart",
-                "autocomplete",
-                "autocompleteerror",
-                "auxclick",
-                "beforeactivate",
-                "beforecopy",
-                "beforecut",
-                "beforedeactivate",
-                "beforeeditfocus",
-                "beforeinstallprompt",
-                "beforepaste",
-                "beforeprint",
-                "beforescriptexecute",
-                "beforeunload",
-                "beforeupdate",
-                "blocked",
-                "blur",
-                "bounce",
-                "boundary",
-                "cached",
-                "cancel",
-                "candidatewindowhide",
-                "candidatewindowshow",
-                "candidatewindowupdate",
-                "canplay",
-                "canplaythrough",
-                "cellchange",
-                "change",
-                "chargingchange",
-                "chargingtimechange",
-                "checking",
-                "click",
-                "close",
-                "compassneedscalibration",
-                "complete",
-                "connect",
-                "connecting",
-                "connectionstatechange",
-                "contextmenu",
-                "controllerchange",
-                "controlselect",
-                "copy",
-                "cuechange",
-                "cut",
-                "dataavailable",
-                "datachannel",
-                "datasetchanged",
-                "datasetcomplete",
-                "dblclick",
-                "deactivate",
-                "devicechange",
-                "devicelight",
-                "devicemotion",
-                "deviceorientation",
-                "deviceorientationabsolute",
-                "deviceproximity",
-                "dischargingtimechange",
-                "disconnect",
-                "display",
-                "downloading",
-                "drag",
-                "dragend",
-                "dragenter",
-                "dragexit",
-                "dragleave",
-                "dragover",
-                "dragstart",
-                "drop",
-                "durationchange",
-                "emptied",
-                "encrypted",
-                "end",
-                "ended",
-                "enter",
-                "enterpictureinpicture",
-                "error",
-                "errorupdate",
-                "exit",
-                "filterchange",
-                "finish",
-                "focus",
-                "focusin",
-                "focusout",
-                "freeze",
-                "fullscreenchange",
-                "fullscreenerror",
-                "gesturechange",
-                "gestureend",
-                "gesturestart",
-                "gotpointercapture",
-                "hashchange",
-                "help",
-                "icecandidate",
-                "iceconnectionstatechange",
-                "icegatheringstatechange",
-                "inactive",
-                "input",
-                "invalid",
-                "keydown",
-                "keypress",
-                "keyup",
-                "languagechange",
-                "layoutcomplete",
-                "leavepictureinpicture",
-                "levelchange",
-                "load",
-                "loadeddata",
-                "loadedmetadata",
-                "loadend",
-                "loading",
-                "loadingdone",
-                "loadingerror",
-                "loadstart",
-                "losecapture",
-                "lostpointercapture",
-                "mark",
-                "message",
-                "messageerror",
-                "mousedown",
-                "mouseenter",
-                "mouseleave",
-                "mousemove",
-                "mouseout",
-                "mouseover",
-                "mouseup",
-                "mousewheel",
-                "move",
-                "moveend",
-                "movestart",
-                "mozfullscreenchange",
-                "mozfullscreenerror",
-                "mozorientationchange",
-                "mozpointerlockchange",
-                "mozpointerlockerror",
-                "mscontentzoom",
-                "msfullscreenchange",
-                "msfullscreenerror",
-                "msgesturechange",
-                "msgesturedoubletap",
-                "msgestureend",
-                "msgesturehold",
-                "msgesturestart",
-                "msgesturetap",
-                "msgotpointercapture",
-                "msinertiastart",
-                "mslostpointercapture",
-                "msmanipulationstatechanged",
-                "msneedkey",
-                "msorientationchange",
-                "mspointercancel",
-                "mspointerdown",
-                "mspointerenter",
-                "mspointerhover",
-                "mspointerleave",
-                "mspointermove",
-                "mspointerout",
-                "mspointerover",
-                "mspointerup",
-                "mssitemodejumplistitemremoved",
-                "msthumbnailclick",
-                "negotiationneeded",
-                "nomatch",
-                "noupdate",
-                "obsolete",
-                "offline",
-                "online",
-                "open",
-                "orientationchange",
-                "pagechange",
-                "pagehide",
-                "pageshow",
-                "paste",
-                "pause",
-                "play",
-                "playing",
-                "pluginstreamstart",
-                "pointercancel",
-                "pointerdown",
-                "pointerenter",
-                "pointerleave",
-                "pointerlockchange",
-                "pointerlockerror",
-                "pointermove",
-                "pointerout",
-                "pointerover",
-                "pointerup",
-                "popstate",
-                "progress",
-                "propertychange",
-                "ratechange",
-                "reading",
-                "readystatechange",
-                "rejectionhandled",
-                "removesourcebuffer",
-                "removestream",
-                "removetrack",
-                "reset",
-                "resize",
-                "resizeend",
-                "resizestart",
-                "resourcetimingbufferfull",
-                "result",
-                "resume",
-                "rowenter",
-                "rowexit",
-                "rowsdelete",
-                "rowsinserted",
-                "scroll",
-                "search",
-                "seeked",
-                "seeking",
-                "select",
-                "selectionchange",
-                "selectstart",
-                "show",
-                "signalingstatechange",
-                "soundend",
-                "soundstart",
-                "sourceclose",
-                "sourceclosed",
-                "sourceended",
-                "sourceopen",
-                "speechend",
-                "speechstart",
-                "stalled",
-                "start",
-                "statechange",
-                "stop",
-                "storage",
-                "storagecommit",
-                "submit",
-                "success",
-                "suspend",
-                "textinput",
-                "timeout",
-                "timeupdate",
-                "toggle",
-                "touchcancel",
-                "touchend",
-                "touchmove",
-                "touchstart",
-                "track",
-                "transitioncancel",
-                "transitionend",
-                "transitionrun",
-                "transitionstart",
-                "unhandledrejection",
-                "unload",
-                "updateready",
-                "upgradeneeded",
-                "userproximity",
-                "versionchange",
-                "visibilitychange",
-                "voiceschanged",
-                "volumechange",
-                "vrdisplayactivate",
-                "vrdisplayconnect",
-                "vrdisplaydeactivate",
-                "vrdisplaydisconnect",
-                "vrdisplaypresentchange",
-                "waiting",
-                "waitingforkey",
-                "warning",
-                "webkitanimationend",
-                "webkitanimationiteration",
-                "webkitanimationstart",
-                "webkitcurrentplaybacktargetiswirelesschanged",
-                "webkitfullscreenchange",
-                "webkitfullscreenerror",
-                "webkitkeyadded",
-                "webkitkeyerror",
-                "webkitkeymessage",
-                "webkitneedkey",
-                "webkitorientationchange",
-                "webkitplaybacktargetavailabilitychanged",
-                "webkitpointerlockchange",
-                "webkitpointerlockerror",
-                "webkitresourcetimingbufferfull",
-                "webkittransitionend",
-                "wheel",
-                "zoom",
-            ].forEach(function(type) {
-                [
-                    "beforeunloadevent",
-                    "compositionevent",
-                    "customevent",
-                    "devicemotionevent",
-                    "deviceorientationevent",
-                    "dragevent",
-                    "event",
-                    "events",
-                    "focusevent",
-                    "hashchangeevent",
-                    "htmlevents",
-                    "keyboardevent",
-                    "messageevent",
-                    "mouseevent",
-                    "mouseevents",
-                    "storageevent",
-                    "svgevents",
-                    "textevent",
-                    "touchevent",
-                    "uievent",
-                    "uievents",
-                ].forEach(function(interface) {
-                    try {
-                        var event = document.createEvent(interface);
-                        event.initEvent(type, true, true);
-                        scan(event);
-                    } catch (e) {}
-                });
-            });
-
-            var obj;
-            while (obj = to_scan.shift()) {
-                var proto = obj;
-                do {
-                    Object.getOwnPropertyNames(proto).forEach(function(name) {
-                        var visited = ~names.indexOf(name);
-                        if (!visited) names.push(name);
-                        try {
-                            scan(obj[name]);
-                            if (visited) return;
-                            if (/^create/.test(name)) {
-                                scan(obj[name]());
-                            }
-                            if (/^[A-Z]/.test(name)) {
-                                scan(new obj[name]());
-                            }
-                        } catch (e) {}
-                    });
-                } while (proto = Object.getPrototypeOf(proto));
-            }
-            names.sort();
-            document.write('<pre>[\n    "');
-            document.write(names.join('",\n    "'));
-            document.write('"\n]</pre>');
-        }();
-    </script>
-</body>
-</html>