v3.11.4

fixes #4242

.github/workflows/ci.yml

@@ -1,5 +1,8 @@
 name: CI
-on: [ push, pull_request ]
+on:
+  pull_request:
+  push:
+    branches: [ master ]
 jobs:
   test:
     strategy:
@@ -8,6 +11,8 @@ jobs:
         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 }}
@@ -17,7 +22,7 @@ jobs:
       TYPE: ${{ matrix.script }}
     steps:
       - uses: actions/checkout@v2
-      - uses: actions/cache@v1
+      - uses: actions/cache@v2
         with:
           path: tmp
           key: tmp ${{ matrix.script }}
@@ -27,7 +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

.github/workflows/ufuzz.yml

@@ -1,7 +1,13 @@
 name: Fuzzing
 on:
+  pull_request:
   schedule:
-    - cron: "*/8 * * * *"
+    - 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:
@@ -16,13 +22,13 @@ jobs:
         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
@@ -31,4 +37,8 @@ jobs:
           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

@@ -4,8 +4,8 @@ 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@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` only supports JavaScript (ECMAScript 5).
 - To minify ECMAScript 2015 or above, transpile using tools like [Babel](https://babeljs.io/).
 
@@ -212,17 +212,16 @@ 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.
+- `reserved` (default: `[]`) -- when mangling is enabled but you want to
+  prevent certain names from being mangled, you can declare those names with
+  `--mangle reserved` — pass a comma-separated list of names.  For example:
 
-When mangling is enabled but you want to prevent certain names from being
-mangled, you can declare those names with `--mangle reserved` — pass a
-comma-separated list of names.  For example:
+      uglifyjs ... -m reserved=['$','require','exports']
 
-    uglifyjs ... -m reserved=['$','require','exports']
-
-to prevent the `require`, `exports` and `$` names from being changed.
+  to prevent the `require`, `exports` and `$` names from being changed.
 
 ### CLI mangling property names (`--mangle-props`)
 
@@ -657,8 +656,8 @@ to be `false` and all symbol names will be omitted.
 - `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)
@@ -689,6 +688,8 @@ to be `false` and all symbol names will be omitted.
 - `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.
@@ -783,6 +784,9 @@ to be `false` and all symbol names will be omitted.
 - `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
@@ -913,7 +917,7 @@ 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
 
@@ -1072,8 +1076,8 @@ 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
@@ -1157,3 +1161,19 @@ 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()`).
+- 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);
+  ```

appveyor.yml

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

bin/uglifyjs

@@ -8,183 +8,252 @@ 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 toplevels = [];
-    var padding = "";
-    var options = UglifyJS.default_options();
-    for (var name in options) {
-        var option = options[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]);
+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
-        }).value;
+}
+
+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.",
+                "  --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;
+        }
+        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":
+        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";
+        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 (!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 (!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 (program.verbose) {
-    options.warnings = "verbose";
-} else if (program.warn) {
-    options.warnings = true;
+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();
@@ -205,15 +274,14 @@ 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);
         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,
@@ -221,7 +289,7 @@ 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;
@@ -233,17 +301,17 @@ 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, {
+        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 {
-        var result = UglifyJS.minify(files, options);
+    } else {
+        result = UglifyJS.minify(files, options);
     }
     if (result.error) {
         var ex = result.error;
@@ -273,9 +341,18 @@ 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) {
@@ -302,26 +379,22 @@ 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");
     }
@@ -377,47 +450,45 @@ function read_file(path, default_value) {
     }
 }
 
-function parse_js(flag) {
-    return function(value, options) {
-        options = options || {};
-        try {
-            UglifyJS.parse(value, {
-                expression: true
-            }).walk(new UglifyJS.TreeWalker(function(node) {
-                if (node instanceof UglifyJS.AST_Assign) {
-                    var name = node.left.print_to_string();
-                    var value = node.right;
-                    if (flag) {
-                        options[name] = value;
-                    } else if (value instanceof UglifyJS.AST_Array) {
-                        options[name] = value.elements.map(to_string);
-                    } else {
-                        options[name] = to_string(value);
-                    }
-                    return true;
+function parse_js(value, options, flag) {
+    if (!options || typeof options != "object") options = {};
+    if (typeof value == "string") try {
+        UglifyJS.parse(value, {
+            expression: true
+        }).walk(new UglifyJS.TreeWalker(function(node) {
+            if (node instanceof UglifyJS.AST_Assign) {
+                var name = node.left.print_to_string();
+                var value = node.right;
+                if (flag) {
+                    options[name] = value;
+                } else if (value instanceof UglifyJS.AST_Array) {
+                    options[name] = value.elements.map(to_string);
+                } else {
+                    options[name] = to_string(value);
                 }
-                if (node instanceof UglifyJS.AST_Symbol || node instanceof UglifyJS.AST_PropAccess) {
-                    var name = node.print_to_string();
-                    options[name] = true;
-                    return true;
-                }
-                if (!(node instanceof UglifyJS.AST_Sequence)) throw node;
-
-                function to_string(value) {
-                    return value instanceof UglifyJS.AST_Constant ? value.value : value.print_to_string({
-                        quote_keys: true
-                    });
-                }
-            }));
-        } catch (ex) {
-            if (flag) {
-                fatal("cannot parse arguments for '" + flag + "': " + value);
-            } else {
-                options[value] = null;
+                return true;
             }
+            if (node instanceof UglifyJS.AST_Symbol || node instanceof UglifyJS.AST_PropAccess) {
+                var name = node.print_to_string();
+                options[name] = true;
+                return true;
+            }
+            if (!(node instanceof UglifyJS.AST_Sequence)) throw node;
+
+            function to_string(value) {
+                return value instanceof UglifyJS.AST_Constant ? value.value : value.print_to_string({
+                    quote_keys: true
+                });
+            }
+        }));
+    } catch (ex) {
+        if (flag) {
+            fatal("cannot parse arguments for '" + flag + "': " + value);
+        } else {
+            options[value] = null;
         }
-        return options;
     }
+    return options;
 }
 
 function skip_key(key) {

lib/minify.js

@@ -85,9 +85,11 @@ function minify(files, options) {
             sourceMap: false,
             timings: false,
             toplevel: false,
+            validate: false,
             warnings: false,
             wrap: false,
         }, true);
+        if (options.validate) AST_Node.enable_validation();
         var timings = options.timings && {
             start: Date.now()
         };
@@ -176,13 +178,17 @@ 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();
@@ -191,9 +197,7 @@ 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) {
@@ -253,5 +257,7 @@ function minify(files, options) {
         return result;
     } catch (ex) {
         return { error: ex };
+    } finally {
+        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) ---------------------------------
 
@@ -111,7 +111,7 @@
             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);
@@ -212,7 +212,14 @@
                             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 +252,6 @@
     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");
@@ -407,6 +413,10 @@
         };
     });
 
+    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/output.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -100,13 +100,16 @@ function OutputStream(options) {
         }
     }
 
-    var indentation = 0;
+    var indentation = options.indent_start;
     var current_col = 0;
     var current_line = 1;
     var current_pos = 0;
     var OUTPUT = "";
 
     var to_utf8 = options.ascii_only ? function(str, identifier) {
+        if (identifier) str = str.replace(/[\ud800-\udbff][\udc00-\udfff]/g, function(ch) {
+            return "\\u{" + (ch.charCodeAt(0) - 0xd7c0 << 10 | ch.charCodeAt(1) - 0xdc00).toString(16) + "}";
+        });
         return str.replace(/[\u0000-\u001f\u007f-\uffff]/g, function(ch) {
             var code = ch.charCodeAt(0).toString(16);
             if (code.length <= 2 && !identifier) {
@@ -191,10 +194,6 @@ function OutputStream(options) {
         return name;
     }
 
-    function make_indent(back) {
-        return repeat_string(" ", options.indent_start + indentation - back * options.indent_level);
-    }
-
     /* -----[ beautification/minification ]----- */
 
     var has_parens = false;
@@ -305,6 +304,7 @@ function OutputStream(options) {
                 || (ch == "/" && ch == prev)
                 || ((ch == "+" || ch == "-") && ch == last)
                 || str == "--" && last == "!"
+                || str == "in" && prev == "/"
                 || last == "--" && ch == ">") {
                 OUTPUT += " ";
                 current_col++;
@@ -344,9 +344,7 @@ function OutputStream(options) {
     };
 
     var indent = options.beautify ? function(half) {
-        if (options.beautify) {
-            print(make_indent(half ? 0.5 : 0));
-        }
+        print(repeat_string(" ", half ? indentation - (options.indent_level >> 1) : indentation));
     } : noop;
 
     var with_indent = options.beautify ? function(col, cont) {
@@ -574,9 +572,9 @@ function OutputStream(options) {
         get             : get,
         toString        : get,
         indent          : indent,
-        indentation     : function() { return indentation },
-        current_width   : function() { return current_col - indentation },
-        should_break    : function() { return options.width && this.current_width() >= options.width },
+        should_break    : readonly ? noop : function() {
+            return options.width && current_col - indentation >= options.width;
+        },
         has_parens      : function() { return has_parens },
         newline         : newline,
         print           : print,
@@ -629,13 +627,7 @@ function OutputStream(options) {
     var use_asm = false;
 
     AST_Node.DEFMETHOD("print", function(stream, force_parens) {
-        var self = this, generator = self._codegen;
-        function doit() {
-            stream.prepend_comments(self);
-            self.add_source_map(stream);
-            generator(self, stream);
-            stream.append_comments(self);
-        }
+        var self = this;
         stream.push_node(self);
         if (force_parens || self.needs_parens(stream)) {
             stream.with_parens(doit);
@@ -643,9 +635,14 @@ function OutputStream(options) {
             doit();
         }
         stream.pop_node();
-    });
-    AST_Node.DEFMETHOD("_print", AST_Node.prototype.print);
 
+        function doit() {
+            stream.prepend_comments(self);
+            self.add_source_map(stream);
+            self._codegen(stream);
+            stream.append_comments(self);
+        }
+    });
     AST_Node.DEFMETHOD("print_to_string", function(options) {
         var s = OutputStream(options);
         this.print(s);
@@ -688,78 +685,66 @@ function OutputStream(options) {
 
     PARENS(AST_Unary, function(output) {
         var p = output.parent();
-        return p instanceof AST_PropAccess && p.expression === this
-            || p instanceof AST_Call && p.expression === this;
+        return (p instanceof AST_Call || p instanceof AST_PropAccess) && p.expression === this;
     });
 
     PARENS(AST_Sequence, function(output) {
         var p = output.parent();
-            // (foo, bar)() or foo(1, (2, 3), 4)
-        return p instanceof AST_Call
-            // !(foo, bar, baz)
-            || p instanceof AST_Unary
+            // [ 1, (2, 3), 4 ] ==> [ 1, 3, 4 ]
+        return p instanceof AST_Array
             // 1 + (2, 3) + 4 ==> 8
             || p instanceof AST_Binary
-            // var a = (1, 2), b = a + a; ==> b == 4
-            || p instanceof AST_VarDef
-            // (1, {foo:2}).foo or (1, {foo:2})["foo"] ==> 2
-            || p instanceof AST_PropAccess && p.expression === this
-            // [ 1, (2, 3), 4 ] ==> [ 1, 3, 4 ]
-            || p instanceof AST_Array
-            // { foo: (1, 2) }.foo ==> 2
-            || p instanceof AST_ObjectProperty
+            // new (foo, bar) or foo(1, (2, 3), 4)
+            || p instanceof AST_Call
             // (false, true) ? (a = 10, b = 20) : (c = 30)
             // ==> 20 (side effect, set a := 10 and b := 20)
-            || p instanceof AST_Conditional;
+            || p instanceof AST_Conditional
+            // { foo: (1, 2) }.foo ==> 2
+            || p instanceof AST_ObjectProperty
+            // (1, {foo:2}).foo or (1, {foo:2})["foo"] ==> 2
+            || p instanceof AST_PropAccess && p.expression === this
+            // !(foo, bar, baz)
+            || p instanceof AST_Unary
+            // var a = (1, 2), b = a + a; ==> b == 4
+            || p instanceof AST_VarDef;
     });
 
     PARENS(AST_Binary, function(output) {
         var p = output.parent();
-        // (foo && bar)()
-        if (p instanceof AST_Call && p.expression === this)
-            return true;
-        // typeof (foo && bar)
-        if (p instanceof AST_Unary)
-            return true;
-        // (foo && bar)["prop"], (foo && bar).prop
-        if (p instanceof AST_PropAccess && p.expression === this)
-            return true;
         // this deals with precedence: 3 * (2 + 1)
         if (p instanceof AST_Binary) {
             var po = p.operator, pp = PRECEDENCE[po];
             var so = this.operator, sp = PRECEDENCE[so];
-            if (pp > sp
-                || (pp == sp
-                    && this === p.right)) {
-                return true;
-            }
+            return pp > sp || (pp == sp && this === p.right);
         }
+        // (foo && bar)()
+        if (p instanceof AST_Call) return p.expression === this;
+        // (foo && bar)["prop"], (foo && bar).prop
+        if (p instanceof AST_PropAccess) return p.expression === this;
+        // typeof (foo && bar)
+        if (p instanceof AST_Unary) return true;
     });
 
     PARENS(AST_PropAccess, function(output) {
+        var node = this;
         var p = output.parent();
-        if (p instanceof AST_New && p.expression === this) {
-            // i.e. new (foo.bar().baz)
+        if (p instanceof AST_New && p.expression === node) {
+            // i.e. new (foo().bar)
             //
             // if there's one call into this subtree, then we need
             // parens around it too, otherwise the call will be
             // interpreted as passing the arguments to the upper New
             // expression.
-            var parens = false;
-            this.walk(new TreeWalker(function(node) {
-                if (parens || node instanceof AST_Scope) return true;
-                if (node instanceof AST_Call) {
-                    parens = true;
-                    return true;
-                }
-            }));
-            return parens;
+            do {
+                node = node.expression;
+            } while (node instanceof AST_PropAccess);
+            return node.TYPE == "Call";
         }
     });
 
     PARENS(AST_Call, function(output) {
         var p = output.parent();
-        if (p instanceof AST_New && p.expression === this) return true;
+        if (p instanceof AST_New) return p.expression === this;
         // https://bugs.webkit.org/show_bug.cgi?id=123506
         if (output.option('webkit')) {
             var g = output.parent(1);
@@ -772,49 +757,43 @@ function OutputStream(options) {
     });
 
     PARENS(AST_New, function(output) {
+        if (need_constructor_parens(this, output)) return false;
         var p = output.parent();
-        if (!need_constructor_parens(this, output)
-            && (p instanceof AST_PropAccess // (new Date).getTime(), (new Date)["getTime"]()
-                || p instanceof AST_Call && p.expression === this)) // (new foo)(bar)
-            return true;
+        // (new foo)(bar)
+        if (p instanceof AST_Call) return p.expression === this;
+        // (new Date).getTime(), (new Date)["getTime"]()
+        return p instanceof AST_PropAccess;
     });
 
     PARENS(AST_Number, function(output) {
         var p = output.parent();
         if (p instanceof AST_PropAccess && p.expression === this) {
             var value = this.value;
-            // https://github.com/mishoo/UglifyJS2/issues/115
-            // https://github.com/mishoo/UglifyJS2/pull/1009
-            if (value < 0 || /^0/.test(make_num(value))) {
-                return true;
-            }
+            // https://github.com/mishoo/UglifyJS/issues/115
+            // https://github.com/mishoo/UglifyJS/pull/1009
+            return value < 0 || /^0/.test(make_num(value));
         }
     });
 
     PARENS([ AST_Assign, AST_Conditional ], function(output) {
         var p = output.parent();
-        // !(a = false) → true
-        if (p instanceof AST_Unary)
-            return true;
         // 1 + (a = 2) + 3 → 6, side effect setting a = 2
-        if (p instanceof AST_Binary && !(p instanceof AST_Assign))
-            return true;
+        if (p instanceof AST_Binary) return !(p instanceof AST_Assign);
         // (a = func)() —or— new (a = Object)()
-        if (p instanceof AST_Call && p.expression === this)
-            return true;
+        if (p instanceof AST_Call) return p.expression === this;
         // (a = foo) ? bar : baz
-        if (p instanceof AST_Conditional && p.condition === this)
-            return true;
+        if (p instanceof AST_Conditional) return p.condition === this;
         // (a = foo)["prop"] —or— (a = foo).prop
-        if (p instanceof AST_PropAccess && p.expression === this)
-            return true;
+        if (p instanceof AST_PropAccess) return p.expression === this;
+        // !(a = false) → true
+        if (p instanceof AST_Unary) return true;
     });
 
     /* -----[ PRINTERS ]----- */
 
-    DEFPRINT(AST_Directive, function(self, output) {
-        var quote = self.quote;
-        var value = self.value;
+    DEFPRINT(AST_Directive, function(output) {
+        var quote = this.quote;
+        var value = this.value;
         switch (output.option("quote_style")) {
           case 0:
           case 2:
@@ -827,7 +806,7 @@ function OutputStream(options) {
         output.print(quote + value + quote);
         output.semicolon();
     });
-    DEFPRINT(AST_Debugger, function(self, output) {
+    DEFPRINT(AST_Debugger, function(output) {
         output.print("debugger");
         output.semicolon();
     });
@@ -859,25 +838,21 @@ function OutputStream(options) {
         use_asm = was_asm;
     }
 
-    AST_StatementWithBody.DEFMETHOD("_do_print_body", function(output) {
-        force_statement(this.body, output);
-    });
-
-    DEFPRINT(AST_Statement, function(self, output) {
-        self.body.print(output);
+    DEFPRINT(AST_Statement, function(output) {
+        this.body.print(output);
         output.semicolon();
     });
-    DEFPRINT(AST_Toplevel, function(self, output) {
-        display_body(self.body, true, output, true);
+    DEFPRINT(AST_Toplevel, function(output) {
+        display_body(this.body, true, output, true);
         output.print("");
     });
-    DEFPRINT(AST_LabeledStatement, function(self, output) {
-        self.label.print(output);
+    DEFPRINT(AST_LabeledStatement, function(output) {
+        this.label.print(output);
         output.colon();
-        self.body.print(output);
+        this.body.print(output);
     });
-    DEFPRINT(AST_SimpleStatement, function(self, output) {
-        self.body.print(output);
+    DEFPRINT(AST_SimpleStatement, function(output) {
+        this.body.print(output);
         output.semicolon();
     });
     function print_braced_empty(self, output) {
@@ -894,13 +869,14 @@ function OutputStream(options) {
             });
         } else print_braced_empty(self, output);
     }
-    DEFPRINT(AST_BlockStatement, function(self, output) {
-        print_braced(self, output);
+    DEFPRINT(AST_BlockStatement, function(output) {
+        print_braced(this, output);
     });
-    DEFPRINT(AST_EmptyStatement, function(self, output) {
+    DEFPRINT(AST_EmptyStatement, function(output) {
         output.semicolon();
     });
-    DEFPRINT(AST_Do, function(self, output) {
+    DEFPRINT(AST_Do, function(output) {
+        var self = this;
         output.print("do");
         output.space();
         make_block(self.body, output);
@@ -912,16 +888,18 @@ function OutputStream(options) {
         });
         output.semicolon();
     });
-    DEFPRINT(AST_While, function(self, output) {
+    DEFPRINT(AST_While, function(output) {
+        var self = this;
         output.print("while");
         output.space();
         output.with_parens(function() {
             self.condition.print(output);
         });
         output.space();
-        self._do_print_body(output);
+        force_statement(self.body, output);
     });
-    DEFPRINT(AST_For, function(self, output) {
+    DEFPRINT(AST_For, function(output) {
+        var self = this;
         output.print("for");
         output.space();
         output.with_parens(function() {
@@ -948,9 +926,10 @@ function OutputStream(options) {
             }
         });
         output.space();
-        self._do_print_body(output);
+        force_statement(self.body, output);
     });
-    DEFPRINT(AST_ForIn, function(self, output) {
+    DEFPRINT(AST_ForIn, function(output) {
+        var self = this;
         output.print("for");
         output.space();
         output.with_parens(function() {
@@ -961,20 +940,21 @@ function OutputStream(options) {
             self.object.print(output);
         });
         output.space();
-        self._do_print_body(output);
+        force_statement(self.body, output);
     });
-    DEFPRINT(AST_With, function(self, output) {
+    DEFPRINT(AST_With, function(output) {
+        var self = this;
         output.print("with");
         output.space();
         output.with_parens(function() {
             self.expression.print(output);
         });
         output.space();
-        self._do_print_body(output);
+        force_statement(self.body, output);
     });
 
     /* -----[ functions ]----- */
-    AST_Lambda.DEFMETHOD("_do_print", function(output, nokeyword) {
+    DEFPRINT(AST_Lambda, function(output, nokeyword) {
         var self = this;
         if (!nokeyword) {
             output.print("function");
@@ -992,37 +972,28 @@ function OutputStream(options) {
         output.space();
         print_braced(self, output, true);
     });
-    DEFPRINT(AST_Lambda, function(self, output) {
-        self._do_print(output);
-    });
 
     /* -----[ jumps ]----- */
-    function print_jump(output, kind, target) {
-        output.print(kind);
-        if (target) {
-            output.space();
-            target.print(output);
-        }
-        output.semicolon();
+    function print_jump(kind, prop) {
+        return function(output) {
+            output.print(kind);
+            var target = this[prop];
+            if (target) {
+                output.space();
+                target.print(output);
+            }
+            output.semicolon();
+        };
     }
-
-    DEFPRINT(AST_Return, function(self, output) {
-        print_jump(output, "return", self.value);
-    });
-    DEFPRINT(AST_Throw, function(self, output) {
-        print_jump(output, "throw", self.value);
-    });
-    DEFPRINT(AST_Break, function(self, output) {
-        print_jump(output, "break", self.label);
-    });
-    DEFPRINT(AST_Continue, function(self, output) {
-        print_jump(output, "continue", self.label);
-    });
+    DEFPRINT(AST_Return, print_jump("return", "value"));
+    DEFPRINT(AST_Throw, print_jump("throw", "value"));
+    DEFPRINT(AST_Break, print_jump("break", "label"));
+    DEFPRINT(AST_Continue, print_jump("continue", "label"));
 
     /* -----[ if ]----- */
     function make_then(self, output) {
         var b = self.body;
-        if (output.option("braces")
+        if (output.option("braces") && !(b instanceof AST_Const || b instanceof AST_Let)
             || output.option("ie8") && b instanceof AST_Do)
             return make_block(b, output);
         // The squeezer replaces "block"-s that contain only a single
@@ -1046,7 +1017,8 @@ function OutputStream(options) {
         }
         force_statement(self.body, output);
     }
-    DEFPRINT(AST_If, function(self, output) {
+    DEFPRINT(AST_If, function(output) {
+        var self = this;
         output.print("if");
         output.space();
         output.with_parens(function() {
@@ -1063,12 +1035,13 @@ function OutputStream(options) {
             else
                 force_statement(self.alternative, output);
         } else {
-            self._do_print_body(output);
+            force_statement(self.body, output);
         }
     });
 
     /* -----[ switch ]----- */
-    DEFPRINT(AST_Switch, function(self, output) {
+    DEFPRINT(AST_Switch, function(output) {
+        var self = this;
         output.print("switch");
         output.space();
         output.with_parens(function() {
@@ -1086,28 +1059,30 @@ function OutputStream(options) {
             });
         });
     });
-    AST_SwitchBranch.DEFMETHOD("_do_print_body", function(output) {
+    function print_branch_body(self, output) {
         output.newline();
-        this.body.forEach(function(stmt) {
+        self.body.forEach(function(stmt) {
             output.indent();
             stmt.print(output);
             output.newline();
         });
-    });
-    DEFPRINT(AST_Default, function(self, output) {
+    }
+    DEFPRINT(AST_Default, function(output) {
         output.print("default:");
-        self._do_print_body(output);
+        print_branch_body(this, output);
     });
-    DEFPRINT(AST_Case, function(self, output) {
+    DEFPRINT(AST_Case, function(output) {
+        var self = this;
         output.print("case");
         output.space();
         self.expression.print(output);
         output.print(":");
-        self._do_print_body(output);
+        print_branch_body(self, output);
     });
 
     /* -----[ exceptions ]----- */
-    DEFPRINT(AST_Try, function(self, output) {
+    DEFPRINT(AST_Try, function(output) {
+        var self = this;
         output.print("try");
         output.space();
         print_braced(self, output);
@@ -1120,36 +1095,45 @@ function OutputStream(options) {
             self.bfinally.print(output);
         }
     });
-    DEFPRINT(AST_Catch, function(self, output) {
+    DEFPRINT(AST_Catch, function(output) {
+        var self = this;
         output.print("catch");
-        output.space();
-        output.with_parens(function() {
-            self.argname.print(output);
-        });
+        if (self.argname) {
+            output.space();
+            output.with_parens(function() {
+                self.argname.print(output);
+            });
+        }
         output.space();
         print_braced(self, output);
     });
-    DEFPRINT(AST_Finally, function(self, output) {
+    DEFPRINT(AST_Finally, function(output) {
         output.print("finally");
         output.space();
-        print_braced(self, output);
+        print_braced(this, output);
     });
 
-    DEFPRINT(AST_Var, function(self, output) {
-        output.print("var");
-        output.space();
-        self.definitions.forEach(function(def, i) {
-            if (i) output.comma();
-            def.print(output);
-        });
-        var p = output.parent();
-        if (p && p.init !== self || !(p instanceof AST_For || p instanceof AST_ForIn)) output.semicolon();
-    });
+    function print_definitinos(type) {
+        return function(output) {
+            var self = this;
+            output.print(type);
+            output.space();
+            self.definitions.forEach(function(def, i) {
+                if (i) output.comma();
+                def.print(output);
+            });
+            var p = output.parent();
+            if (p && p.init !== self || !(p instanceof AST_For || p instanceof AST_ForIn)) output.semicolon();
+        };
+    }
+    DEFPRINT(AST_Const, print_definitinos("const"));
+    DEFPRINT(AST_Let, print_definitinos("let"));
+    DEFPRINT(AST_Var, print_definitinos("var"));
 
     function parenthesize_for_noin(node, output, noin) {
         var parens = false;
         // need to take some precautions here:
-        //    https://github.com/mishoo/UglifyJS2/issues/60
+        //    https://github.com/mishoo/UglifyJS/issues/60
         if (noin) node.walk(new TreeWalker(function(node) {
             if (parens || node instanceof AST_Scope) return true;
             if (node instanceof AST_Binary && node.operator == "in") {
@@ -1160,7 +1144,8 @@ function OutputStream(options) {
         node.print(output, parens);
     }
 
-    DEFPRINT(AST_VarDef, function(self, output) {
+    DEFPRINT(AST_VarDef, function(output) {
+        var self = this;
         self.name.print(output);
         if (self.value) {
             output.space();
@@ -1173,10 +1158,7 @@ function OutputStream(options) {
     });
 
     /* -----[ other expressions ]----- */
-    DEFPRINT(AST_Call, function(self, output) {
-        self.expression.print(output);
-        if (self instanceof AST_New && !need_constructor_parens(self, output))
-            return;
+    function print_call_args(self, output) {
         if (self.expression instanceof AST_Call || self.expression instanceof AST_Lambda) {
             output.add_mapping(self.start);
         }
@@ -1186,14 +1168,20 @@ function OutputStream(options) {
                 expr.print(output);
             });
         });
+    }
+    DEFPRINT(AST_Call, function(output) {
+        this.expression.print(output);
+        print_call_args(this, output);
     });
-    DEFPRINT(AST_New, function(self, output) {
+    DEFPRINT(AST_New, function(output) {
+        var self = this;
         output.print("new");
         output.space();
-        AST_Call.prototype._codegen(self, output);
+        self.expression.print(output);
+        if (need_constructor_parens(self, output)) print_call_args(self, output);
     });
-    DEFPRINT(AST_Sequence, function(self, output) {
-        self.expressions.forEach(function(node, index) {
+    DEFPRINT(AST_Sequence, function(output) {
+        this.expressions.forEach(function(node, index) {
             if (index > 0) {
                 output.comma();
                 if (output.should_break()) {
@@ -1204,7 +1192,8 @@ function OutputStream(options) {
             node.print(output);
         });
     });
-    DEFPRINT(AST_Dot, function(self, output) {
+    DEFPRINT(AST_Dot, function(output) {
+        var self = this;
         var expr = self.expression;
         expr.print(output);
         var prop = self.property;
@@ -1225,35 +1214,38 @@ function OutputStream(options) {
             output.print_name(prop);
         }
     });
-    DEFPRINT(AST_Sub, function(self, output) {
-        self.expression.print(output);
+    DEFPRINT(AST_Sub, function(output) {
+        this.expression.print(output);
         output.print("[");
-        self.property.print(output);
+        this.property.print(output);
         output.print("]");
     });
-    DEFPRINT(AST_UnaryPrefix, function(self, output) {
-        var op = self.operator;
+    DEFPRINT(AST_UnaryPrefix, function(output) {
+        var op = this.operator;
+        var exp = this.expression;
         output.print(op);
         if (/^[a-z]/i.test(op)
             || (/[+-]$/.test(op)
-                && self.expression instanceof AST_UnaryPrefix
-                && /^[+-]/.test(self.expression.operator))) {
+                && exp instanceof AST_UnaryPrefix
+                && /^[+-]/.test(exp.operator))) {
             output.space();
         }
-        self.expression.print(output);
+        exp.print(output);
     });
-    DEFPRINT(AST_UnaryPostfix, function(self, output) {
-        self.expression.print(output);
-        output.print(self.operator);
+    DEFPRINT(AST_UnaryPostfix, function(output) {
+        this.expression.print(output);
+        output.print(this.operator);
     });
-    DEFPRINT(AST_Binary, function(self, output) {
+    DEFPRINT(AST_Binary, function(output) {
+        var self = this;
         self.left.print(output);
         output.space();
         output.print(self.operator);
         output.space();
         self.right.print(output);
     });
-    DEFPRINT(AST_Conditional, function(self, output) {
+    DEFPRINT(AST_Conditional, function(output) {
+        var self = this;
         self.condition.print(output);
         output.space();
         output.print("?");
@@ -1265,10 +1257,10 @@ function OutputStream(options) {
     });
 
     /* -----[ literals ]----- */
-    DEFPRINT(AST_Array, function(self, output) {
-        output.with_square(function() {
-            var a = self.elements, len = a.length;
-            if (len > 0) output.space();
+    DEFPRINT(AST_Array, function(output) {
+        var a = this.elements, len = a.length;
+        output.with_square(len > 0 ? function() {
+            output.space();
             a.forEach(function(exp, i) {
                 if (i) output.comma();
                 exp.print(output);
@@ -1278,12 +1270,13 @@ function OutputStream(options) {
                 if (i === len - 1 && exp instanceof AST_Hole)
                   output.comma();
             });
-            if (len > 0) output.space();
-        });
+            output.space();
+        } : noop);
     });
-    DEFPRINT(AST_Object, function(self, output) {
-        if (self.properties.length > 0) output.with_block(function() {
-            self.properties.forEach(function(prop, i) {
+    DEFPRINT(AST_Object, function(output) {
+        var props = this.properties;
+        if (props.length > 0) output.with_block(function() {
+            props.forEach(function(prop, i) {
                 if (i) {
                     output.print(",");
                     output.newline();
@@ -1293,7 +1286,7 @@ function OutputStream(options) {
             });
             output.newline();
         });
-        else print_braced_empty(self, output);
+        else print_braced_empty(this, output);
     });
 
     function print_property_name(key, quote, output) {
@@ -1312,47 +1305,48 @@ function OutputStream(options) {
         }
     }
 
-    DEFPRINT(AST_ObjectKeyVal, function(self, output) {
+    DEFPRINT(AST_ObjectKeyVal, function(output) {
+        var self = this;
         print_property_name(self.key, self.quote, output);
         output.colon();
         self.value.print(output);
     });
-    AST_ObjectProperty.DEFMETHOD("_print_getter_setter", function(type, output) {
-        output.print(type);
-        output.space();
-        print_property_name(this.key.name, this.quote, output);
-        this.value._do_print(output, true);
-    });
-    DEFPRINT(AST_ObjectSetter, function(self, output) {
-        self._print_getter_setter("set", output);
-    });
-    DEFPRINT(AST_ObjectGetter, function(self, output) {
-        self._print_getter_setter("get", output);
-    });
-    DEFPRINT(AST_Symbol, function(self, output) {
-        var def = self.definition();
-        output.print_name(def && def.mangled_name || self.name);
+    function print_accessor(type) {
+        return function(output) {
+            var self = this;
+            output.print(type);
+            output.space();
+            print_property_name(self.key.name, self.quote, output);
+            self.value._codegen(output, true);
+        };
+    }
+    DEFPRINT(AST_ObjectGetter, print_accessor("get"));
+    DEFPRINT(AST_ObjectSetter, print_accessor("set"));
+    DEFPRINT(AST_Symbol, function(output) {
+        var def = this.definition();
+        output.print_name(def && def.mangled_name || this.name);
     });
     DEFPRINT(AST_Hole, noop);
-    DEFPRINT(AST_This, function(self, output) {
+    DEFPRINT(AST_This, function(output) {
         output.print("this");
     });
-    DEFPRINT(AST_Constant, function(self, output) {
-        output.print(self.value);
+    DEFPRINT(AST_Constant, function(output) {
+        output.print(this.value);
     });
-    DEFPRINT(AST_String, function(self, output) {
-        output.print_string(self.value, self.quote);
+    DEFPRINT(AST_String, function(output) {
+        output.print_string(this.value, this.quote);
     });
-    DEFPRINT(AST_Number, function(self, output) {
-        if (use_asm && self.start && self.start.raw != null) {
-            output.print(self.start.raw);
+    DEFPRINT(AST_Number, function(output) {
+        var start = this.start;
+        if (use_asm && start && start.raw != null) {
+            output.print(start.raw);
         } else {
-            output.print(make_num(self.value));
+            output.print(make_num(this.value));
         }
     });
 
-    DEFPRINT(AST_RegExp, function(self, output) {
-        var regexp = self.value;
+    DEFPRINT(AST_RegExp, function(output) {
+        var regexp = this.value;
         var str = regexp.toString();
         var end = str.lastIndexOf("/");
         if (regexp.raw_source) {
@@ -1386,18 +1380,17 @@ function OutputStream(options) {
             }
         }));
         var p = output.parent();
-        if (p instanceof AST_Binary && /^in/.test(p.operator) && p.left === self)
+        if (p instanceof AST_Binary && /^in/.test(p.operator) && p.left === this)
             output.print(" ");
     });
 
     function force_statement(stat, output) {
-        if (output.option("braces")) {
+        if (output.option("braces") && !(stat instanceof AST_Const || stat instanceof AST_Let)) {
             make_block(stat, output);
+        } else if (!stat || stat instanceof AST_EmptyStatement) {
+            output.force_semicolon();
         } else {
-            if (!stat || stat instanceof AST_EmptyStatement)
-                output.force_semicolon();
-            else
-                stat.print(output);
+            stat.print(output);
         }
     }
 

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 = [
+    "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,
+].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) {
@@ -181,14 +145,12 @@ 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 val = parseFloat(num);
-        if (val == num) return val;
-    }
+    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) {
@@ -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, "$1");
         }
         var valid = parse_js_number(num);
         if (!isNaN(valid)) return token("num", valid);
@@ -358,20 +322,30 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
     function read_escaped_char(in_string) {
         var ch = next(true, in_string);
         switch (ch.charCodeAt(0)) {
-          case 110 : return "\n";
-          case 114 : return "\r";
-          case 116 : return "\t";
-          case 98  : return "\b";
-          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 13  :            // \r
-            if (peek() == "\n") { // DOS newline
-                next(true, in_string);
-                return "";
-            }
+          case 110: return "\n";
+          case 114: return "\r";
+          case 116: return "\t";
+          case 98:  return "\b";
+          case 118: return "\u000b";                            // \v
+          case 102: return "\f";
+          case 120: return String.fromCharCode(hex_bytes(2));   // \x
+          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
+            // 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();
@@ -587,7 +561,7 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
             if (is_digit(code)) return read_num();
             if (PUNC_CHARS[ch]) return token("punc", next());
             if (OPERATOR_CHARS[ch]) return read_operator();
-            if (code == 92 || is_identifier_start(code)) return read_word();
+            if (code == 92 || !NON_IDENTIFIER_CHARS[ch]) return read_word();
             break;
         }
         parse_error("Unexpected character '" + ch + "'");
@@ -832,6 +806,12 @@ function parse($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);
@@ -874,6 +854,12 @@ 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 +934,7 @@ function parse($TEXT, options) {
         if (!(stat instanceof AST_IterationStatement)) {
             // check for `continue` that refers to this label.
             // those should be reported as syntax errors.
-            // https://github.com/mishoo/UglifyJS2/issues/287
+            // https://github.com/mishoo/UglifyJS/issues/287
             label.references.forEach(function(ref) {
                 if (ref instanceof AST_Continue) {
                     ref = ref.label.start;
@@ -988,7 +974,9 @@ function parse($TEXT, options) {
         expect("(");
         var init = null;
         if (!is("punc", ";")) {
-            init = is("keyword", "var")
+            init = is("keyword", "const")
+                ? (next(), const_(true))
+                : is("keyword", "var")
                 ? (next(), var_(true))
                 : expression(true, true);
             if (is("operator", "in")) {
@@ -1092,7 +1080,7 @@ 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 +1095,14 @@ function parse($TEXT, options) {
                 expect(":");
             } else if (is("keyword", "default")) {
                 if (branch) branch.end = prev();
+                if (default_branch) croak("More than one default clause in switch statement");
                 cur = [];
                 branch = new AST_Default({
                     start : (tmp = S.token, next(), expect(":"), tmp),
                     body  : cur
                 });
                 a.push(branch);
+                default_branch = branch;
             } else {
                 if (!cur) unexpected();
                 cur.push(statement());
@@ -1128,9 +1118,12 @@ function parse($TEXT, options) {
         if (is("keyword", "catch")) {
             var start = S.token;
             next();
-            expect("(");
-            var name = as_symbol(AST_SymbolCatch);
-            expect(")");
+            var name = null;
+            if (is("punc", "(")) {
+                next();
+                name = as_symbol(AST_SymbolCatch);
+                expect(")");
+            }
             bcatch = new AST_Catch({
                 start   : start,
                 argname : name,
@@ -1156,13 +1149,22 @@ function parse($TEXT, options) {
         });
     }
 
-    function vardefs(no_in) {
+    function vardefs(type, no_in, must_init) {
         var a = [];
         for (;;) {
+            var start = S.token;
+            var name = as_symbol(type);
+            var value = null;
+            if (is("operator", "=")) {
+                next();
+                value = expression(false, no_in);
+            } else if (must_init) {
+                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 +1174,26 @@ function parse($TEXT, options) {
         return a;
     }
 
+    var const_ = function(no_in) {
+        return new AST_Const({
+            start       : prev(),
+            definitions : vardefs(AST_SymbolConst, no_in, true),
+            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()
         });
     };

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_ObjectKeyVal) {
+            if (node.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) {
-            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;
-    }));
+    if (node instanceof AST_Conditional) {
+        addStrings(node.consequent, add);
+        addStrings(node.alternative, add);
+    } else if (node instanceof AST_Sequence) {
+        addStrings(node.tail_node(), add);
+    } else if (node instanceof AST_String) {
+        add(node.value);
+    }
 }
 
 function mangle_properties(ast, options) {
@@ -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 +139,92 @@ 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) {
+        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_ObjectKeyVal) {
             add(node.key);
         } else if (node instanceof AST_ObjectProperty) {
             // setter or getter, since KeyVal is handled above
             add(node.key.name);
-        } else if (node instanceof AST_Dot) {
-            add(node.property);
         } 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) {
+    // 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 (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);
-        } 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_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 +248,13 @@ 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]);
-            } 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;
-        }));
+        if (node instanceof AST_Sequence) {
+            mangleStrings(node.expressions.tail_node());
+        } else if (node instanceof AST_String) {
+            node.value = mangle(node.value);
+        } else if (node instanceof AST_Conditional) {
+            mangleStrings(node.consequent);
+            mangleStrings(node.alternative);
+        }
     }
 }

lib/scope.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -59,21 +59,17 @@ function SymbolDef(id, scope, orig, init) {
 }
 
 SymbolDef.prototype = {
-    unmangleable: function(options) {
-        return this.global && !options.toplevel
-            || this.undeclared
-            || !options.eval && this.scope.pinned()
-            || options.keep_fnames
-                && (this.orig[0] instanceof AST_SymbolLambda
-                    || this.orig[0] instanceof AST_SymbolDefun);
+    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;
-            if (def = this.redefined()) {
+            var def = this.redefined();
+            if (def) {
                 this.mangled_name = def.mangled_name || def.name;
             } else {
                 this.mangled_name = next_mangled_name(this.scope, options, this);
@@ -84,8 +80,24 @@ SymbolDef.prototype = {
         }
     },
     redefined: function() {
-        return this.defun && this.defun.variables.get(this.name);
-    }
+        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
+            || !options.eval && this.scope.pinned()
+            || options.keep_fnames
+                && (this.orig[0] instanceof AST_SymbolLambda
+                    || this.orig[0] instanceof AST_SymbolDefun);
+    },
 };
 
 AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
@@ -96,30 +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 (node instanceof AST_Defun) {
+            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;
@@ -128,28 +156,50 @@ 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) {
-                node.mark_enclosed(options);
-                var def = scope.find_variable(node);
-                if (node.thedef !== def) {
-                    node.thedef = def;
-                }
-                node.reference(options);
-            }
-        } else if (node instanceof AST_SymbolCatch) {
-            scope.def_variable(node).defun = defun;
+            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) return;
+            node.thedef = def;
+            def.orig.push(node);
+            node.mark_enclosed(options);
         }
     });
-    self.next_def_id = 0;
+    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
@@ -164,15 +214,18 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
             var sym = node.scope.find_variable(name);
             if (!sym) {
                 sym = self.def_global(node);
-            } else if (sym.scope instanceof AST_Lambda && name == "arguments") {
+            } else if (name == "arguments" && sym.scope instanceof AST_Lambda) {
                 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) {
+                    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;
                 }
@@ -181,7 +234,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
             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) {
@@ -190,6 +243,12 @@ 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;
+        }
     });
     self.walk(tw);
 
@@ -218,10 +277,13 @@ 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);
         }
@@ -230,7 +292,9 @@ 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);
         });
@@ -239,12 +303,6 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
     }
 });
 
-AST_Scope.DEFMETHOD("make_def", function(orig, init) {
-    var top = this;
-    while (top.parent_scope) top = top.parent_scope;
-    return new SymbolDef(++top.next_def_id, this, orig, init);
-});
-
 AST_Toplevel.DEFMETHOD("def_global", function(node) {
     var globals = this.globals, name = node.name;
     if (globals.has(name)) {
@@ -258,24 +316,35 @@ 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) {
@@ -296,20 +365,20 @@ AST_Symbol.DEFMETHOD("reference", function(options) {
     this.mark_enclosed(options);
 });
 
-AST_Scope.DEFMETHOD("find_variable", function(name) {
+AST_BlockScope.DEFMETHOD("find_variable", function(name) {
     if (name instanceof AST_Symbol) name = name.name;
     return this.variables.get(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;
     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);
@@ -322,17 +391,12 @@ AST_Scope.DEFMETHOD("def_variable", function(symbol, init) {
     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;
@@ -349,7 +413,7 @@ function next_mangled_name(scope, options, def) {
     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) {
@@ -365,7 +429,7 @@ 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) {
@@ -374,7 +438,7 @@ 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;
 }
 
@@ -386,18 +450,10 @@ 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,
@@ -423,7 +479,7 @@ 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;
         });
@@ -438,7 +494,11 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
             lname = save_nesting;
             return true;
         }
-        if (node instanceof AST_Scope) {
+        if (node instanceof AST_BlockScope) {
+            var to_mangle = [];
+            node.variables.each(function(def) {
+                if (!defer_redef(def)) to_mangle.push(def);
+            });
             descend();
             if (options.cache && node instanceof AST_Toplevel) {
                 node.globals.each(mangle);
@@ -448,9 +508,7 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
                 sym.scope = node;
                 sym.reference(options);
             }
-            node.variables.each(function(def) {
-                if (!defer_redef(def)) mangle(def);
-            });
+            to_mangle.forEach(mangle);
             return true;
         }
         if (node instanceof AST_Label) {
@@ -461,13 +519,6 @@ 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);
@@ -482,7 +533,8 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
         if (!redef) return false;
         redefined.push(def);
         def.references.forEach(reference);
-        if (node) reference(node);
+        var node = def.orig[0];
+        if (node instanceof AST_SymbolCatch || node instanceof AST_SymbolConst) reference(node);
         return true;
 
         function reference(sym) {
@@ -495,12 +547,11 @@ 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;
 
@@ -524,15 +575,14 @@ 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;
     }
 
@@ -543,11 +593,8 @@ 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;
         });
     }
 });
@@ -560,22 +607,24 @@ 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) ---------------------------------
 

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) {

lib/utils.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -112,48 +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 instanceof Splice) {
-                    top.push.apply(top, backwards ? val.v.slice().reverse() : val.v);
-                } else {
-                    top.push(val);
-                }
-            } else if (val !== skip) {
-                if (val instanceof Splice) {
-                    ret.push.apply(ret, backwards ? val.v.slice().reverse() : val.v);
-                } else {
-                    ret.push(val);
-                }
-            }
-            return is_last;
-        }
-        if (Array.isArray(a)) {
-            if (backwards) {
-                for (i = a.length; --i >= 0;) if (doit()) break;
-                ret.reverse();
-                top.reverse();
+            if (val === skip) continue;
+            if (val instanceof Splice) {
+                ret.push.apply(ret, val.v);
             } else {
-                for (i = 0; i < a.length; ++i) if (doit()) break;
+                ret.push(val);
             }
-        } else {
-            for (i in a) if (HOP(a, i)) if (doit()) break;
         }
-        return top.concat(ret);
+        return ret;
     }
-    List.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;
 })();
 

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": "3.9.2",
+  "version": "3.11.4",
   "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

@@ -8,8 +8,8 @@ var fetch = require("./fetch");
 var spawn = require("child_process").spawn;
 var zlib = require("zlib");
 var args = process.argv.slice(2);
-args.unshift("bin/uglifyjs");
 if (!args.length) args.push("-mc");
+args.unshift("bin/uglifyjs");
 args.push("--timings");
 var urls = [
     "https://code.jquery.com/jquery-3.4.1.js",

test/compress.js

@@ -63,7 +63,7 @@ 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
+    // TODO try/catch can be removed after fixing https://github.com/mishoo/UglifyJS/issues/348
     try {
         var ast = U.parse(script, {
             filename: file
@@ -188,6 +188,7 @@ 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 +252,7 @@ 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 +269,7 @@ function test_case(test) {
         quote_style: 3,
     });
     try {
+        input.validate_ast();
         U.parse(input_code);
     } catch (ex) {
         log([
@@ -309,12 +312,10 @@ 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);
+    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;
@@ -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 +783,27 @@ 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"
+}

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) {
@@ -91,11 +90,12 @@ asm_mixed: {
         function no_asm_GeometricMean(stdlib, foreign, buffer) {
             function logSum(start, end) {
                 start |= 0, end |= 0;
-                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]);
+                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/collapse_vars.js

@@ -62,25 +62,26 @@ collapse_vars_side_effects_1: {
     expect: {
         function f1() {
             var s = "abcdef", i = 2;
-            console.log.bind(console)(s.charAt(i++), s.charAt(i++), s.charAt(i++), 7);
+            console.log.bind(console)(s.charAt(i++), s.charAt(+i), s.charAt(4), 7);
         }
         function f2() {
             var s = "abcdef", i = 2;
-            console.log.bind(console)(s.charAt(i++), 5, s.charAt(i++), s.charAt(i++), 7);
+            console.log.bind(console)(s.charAt(i++), 5, s.charAt(i++), s.charAt(+i), 7);
         }
         function f3() {
             var s = "abcdef",
                 i = 2,
                 log = console.log.bind(console),
                 x = s.charAt(i++),
-                y = s.charAt(i++);
-            log(x, s.charAt(i++), y, 7);
+                y = s.charAt(+i);
+            log(x, s.charAt(4), y, 7);
         }
         function f4() {
-            var i = 10,
-                x = i += 2,
-                y = i += 3;
-            console.log.bind(console)(x, i += 4, y, 19);
+            var i = 10;
+            i += 2,
+            i += 3,
+            i += 4;
+            console.log.bind(console)(12, 19, 15, 19);
         }
         f1(), f2(), f3(), f4();
     }
@@ -345,9 +346,8 @@ collapse_vars_if: {
             return "x" != "Bar" + x / 4 ? g9 : g5;
         }
         function f3(x) {
-            if (x) {
+            if (x)
                 return 1;
-            }
             return 2;
         }
     }
@@ -916,7 +916,7 @@ collapse_vars_lvalues_drop_assign: {
     }
 }
 
-collapse_vars_misc1: {
+collapse_vars_misc: {
     options = {
         booleans: true,
         collapse_vars: true,
@@ -970,8 +970,8 @@ collapse_vars_misc1: {
         function f7() { var b = window.a * window.z; return b + b }
         function f8() { var b = window.a * window.z; return b + (5 + b) }
         function f9() { var b = window.a * window.z; return bar() || b }
-        function f10(x) { var a = 5; return a += 3; }
-        function f11(x) { var a = 5; return a += 2; }
+        function f10(x) { return 8; }
+        function f11(x) { return 7; }
     }
 }
 
@@ -1598,7 +1598,7 @@ collapse_vars_constants: {
     }
 }
 
-collapse_vars_arguments: {
+collapse_vars_arguments_1: {
     options = {
         booleans: true,
         collapse_vars: true,
@@ -1635,6 +1635,78 @@ collapse_vars_arguments: {
     expect_stdout: true
 }
 
+collapse_vars_arguments_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        function log(a, b) {
+            console.log(b);
+        }
+        function f(c) {
+            var d = arguments[0];
+            c = "FAIL";
+            log(c, d);
+        }
+        f();
+        f("PASS");
+    }
+    expect: {
+        function log(a, b) {
+            console.log(b);
+        }
+        function f(c) {
+            var d = arguments[0];
+            log(c = "FAIL", d);
+        }
+        f();
+        f("PASS");
+    }
+    expect_stdout: [
+        "undefined",
+        "PASS",
+    ]
+}
+
+collapse_vars_arguments_3: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        function log(a, b) {
+            console.log(b);
+        }
+        function f(c) {
+            var args = arguments;
+            console.log(c);
+            var d = args[0];
+            c = "FAIL";
+            log(c, d);
+        }
+        f();
+        f("PASS");
+    }
+    expect: {
+        function log(a, b) {
+            console.log(b);
+        }
+        function f(c) {
+            var args = arguments;
+            console.log(c);
+            var d = args[0];
+            log(c = "FAIL", d);
+        }
+        f();
+        f("PASS");
+    }
+    expect_stdout: [
+        "undefined",
+        "undefined",
+        "PASS",
+        "PASS",
+    ]
+}
+
 collapse_vars_short_circuit: {
     options = {
         booleans: true,
@@ -3000,8 +3072,6 @@ issue_2298: {
     expect: {
         !function() {
             (function() {
-                var a = undefined;
-                var undefined = a++;
                 try {
                     !function(b) {
                         (void 0)[1] = "foo";
@@ -3835,20 +3905,19 @@ issue_2436_3: {
         }(o));
     }
     expect: {
-        var o = {
-            a: 1,
-            b: 2,
-        };
         console.log(function(c) {
-            o = {
+            ({
                 a: 3,
                 b: 4,
-            };
+            });
             return {
                 x: c.a,
                 y: c.b,
             };
-        }(o));
+        }({
+            a: 1,
+            b: 2,
+        }));
     }
     expect_stdout: true
 }
@@ -4070,16 +4139,15 @@ issue_2436_10: {
         }(o).join(" "));
     }
     expect: {
-        var o = {
-            a: 1,
-            b: 2,
-        };
         function f(n) {
-            o = { b: 3 };
+            ({ b: 3 });
             return n;
         }
         console.log([
-            (c = o).a,
+            (c = {
+                a: 1,
+                b: 2,
+            }).a,
             f(c.b),
             c.b,
         ].join(" "));
@@ -4123,9 +4191,8 @@ issue_2436_11: {
             if (isCollection(arg1)) {
                 var size = arg1, max = arg2, min = 0, res = _randomDataForMatrix(size.valueOf(), min, max, _randomInt);
                 return size && true === size.isMatrix ? matrix(res) : res;
-            } else {
+            } else
                 return _randomInt(min = arg1, max = arg2);
-            }
         }
     }
 }
@@ -4241,9 +4308,8 @@ issue_2497: {
         function sample() {
             if (true)
                 for (var i = 0; i < 1; ++i)
-                    for (var k = 0; k < 1; ++k) {
+                    for (var k = 0; k < 1; ++k)
                         value = (value = 1) ? value + 1 : 0;
-                    }
             else
                 for (i = 0; i < 1; ++i)
                     for (k = 0; k < 1; ++k)
@@ -6890,6 +6956,30 @@ sequence_in_iife_2: {
     }
     expect: {
         var a = "foo", b = 42;
+        b = a;
+        console.log(a, b);
+    }
+    expect_stdout: "foo foo"
+}
+
+sequence_in_iife_3: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        passes: 2,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "foo", b = 42;
+        (function() {
+            var c = (b = a, b);
+        })();
+        console.log(a, b);
+    }
+    expect: {
+        var a = "foo";
         console.log(a, a);
     }
     expect_stdout: "foo foo"
@@ -7954,3 +8044,536 @@ mangleable_var: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3884_1: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 100, b = 1;
+        {
+            a++ + a || a;
+            b <<= a;
+        }
+        console.log(a, b);
+    }
+    expect: {
+        var a = 100, b = 1;
+        b <<= ++a;
+        console.log(a, b);
+    }
+    expect_stdout: "101 32"
+}
+
+issue_3884_2: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        passes: 3,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 100, b = 1;
+        {
+            a++ + a || a;
+            b <<= a;
+        }
+        console.log(a, b);
+    }
+    expect: {
+        console.log(101, 32);
+    }
+    expect_stdout: "101 32"
+}
+
+issue_3891: {
+    options = {
+        collapse_vars: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function log(a) {
+            console.log(typeof a);
+        }
+        log(function f() {
+            try {
+                do {
+                    var b = function() {}();
+                } while (f = 0, b.p);
+            } catch (e) {
+                var f;
+                b;
+            }
+        });
+    }
+    expect: {
+        function log(a) {
+            console.log(typeof a);
+        }
+        log(function() {
+            try {
+                do {} while ((void 0).p);
+            } catch (e) {}
+        });
+    }
+    expect_stdout: "function"
+}
+
+issue_3894: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function log(msg) {
+            console.log(msg ? "FAIL" : "PASS");
+        }
+        var a, c;
+        (function(b) {
+            a = c = 0,
+            log(b);
+        })(-0);
+        log(a);
+        log(c);
+    }
+    expect: {
+        function log(msg) {
+            console.log(msg ? "FAIL" : "PASS");
+        }
+        var a, c;
+        void log(-(a = c = 0));
+        log(a);
+        log(c);
+    }
+    expect_stdout: [
+        "PASS",
+        "PASS",
+        "PASS",
+    ]
+}
+
+issue_3897: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = 0;
+        (function() {
+            function f(b) {
+                b = a = 1 + a;
+                a = 1 + a;
+                console.log(b);
+            }
+            f();
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = 0;
+        (function() {
+            function f(b) {
+                b = a = 1 + a;
+                a = 1 + a;
+                console.log(b);
+            }
+            f();
+        })();
+        console.log(a);
+    }
+    expect_stdout: [
+        "1",
+        "2",
+    ]
+}
+
+issue_3908: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        if (console) {
+            var o = {
+                p: !1
+            }, a = o;
+        }
+        console.log("PASS");
+    }
+    expect: {
+        console && 0;
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3927: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = 0;
+        console.log(function(b) {
+            try {
+                try {
+                    if (a + (b = "PASS", true)) return;
+                    b.p;
+                } finally {
+                    return b;
+                }
+            } catch (e) {
+            }
+        }());
+    }
+    expect: {
+        var a = 0;
+        console.log(function(b) {
+            try {
+                try {
+                    if (a + (b = "PASS", true)) return;
+                    b.p;
+                } finally {
+                    return b;
+                }
+            } catch (e) {}
+        }());
+    }
+    expect_stdout: "PASS"
+}
+
+operator_in: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        function log(msg) {
+            console.log(msg);
+        }
+        var a = "FAIL";
+        try {
+            a = "PASS";
+            0 in null;
+            log("FAIL", a);
+        } catch (e) {}
+        log(a);
+    }
+    expect: {
+        function log(msg) {
+            console.log(msg);
+        }
+        var a = "FAIL";
+        try {
+            a = "PASS";
+            0 in null;
+            log("FAIL", a);
+        } catch (e) {}
+        log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3971: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 0 == typeof f, b = 0;
+        {
+            var a = void (a++ + (b |= a));
+        }
+        console.log(b);
+    }
+    expect: {
+        var a = 0 == typeof f, b = 0;
+        var a = void (b |= ++a);
+        console.log(b);
+    }
+    expect_stdout: "1"
+}
+
+issue_3976: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        evaluate: true,
+        inline: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            console.log("FAIL");
+        }
+        (function(a) {
+            function g() {
+                if ((a = 0) || f(0)) {
+                    f();
+                } else {
+                    f();
+                }
+                if (h(a = 0));
+            }
+            function h() {
+                g();
+            }
+        })();
+        console.log("PASS");
+    }
+    expect: {
+        function f() {
+            console.log("FAIL");
+        }
+        void 0;
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4012: {
+    options = {
+        collapse_vars: true,
+        dead_code: true,
+        evaluate: true,
+    }
+    input: {
+        (function(a) {
+            try {
+                throw 2;
+            } catch (b) {
+                a = "PASS";
+                if (--b)
+                    return;
+                if (3);
+            } finally {
+                console.log(a);
+            }
+        })();
+    }
+    expect: {
+        (function(a) {
+            try {
+                throw 2;
+            } catch (b) {
+                a = "PASS";
+                if (--b)
+                    return;
+                if (3);
+            } finally {
+                console.log(a);
+            }
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+global_assign: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        this.A = "FAIL";
+        A = "PASS";
+        B = "FAIL";
+        console.log(A);
+    }
+    expect: {
+        this.A = "FAIL";
+        A = "PASS";
+        B = "FAIL";
+        console.log(A);
+    }
+    expect_stdout: "PASS"
+}
+
+global_read: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = 0;
+        a = this.A;
+        A = 1;
+        a ? console.log("FAIL") : console.log("PASS");
+    }
+    expect: {
+        var a = 0;
+        a = this.A;
+        A = 1;
+        a ? console.log("FAIL") : console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4038: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = 0;
+        a = this;
+        a = a.A;
+        A = 1;
+        a ? console.log("FAIL") : console.log("PASS");
+    }
+    expect: {
+        var a = 0;
+        a = (a = this).A;
+        A = 1;
+        a ? console.log("FAIL") : console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4040: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = console.log("PASS") && a.p;
+        delete NaN;
+    }
+    expect: {
+        var a = console.log("PASS") && a.p;
+        delete NaN;
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4047_1: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        reduce_vars: true,
+        sequences: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var b = 1;
+        console.log(+function(a) {
+            b = a;
+            (a >>= 0) && console.log("PASS");
+        }(--b + (0 !== typeof A)));
+    }
+    expect: {
+        var b = 1;
+        var a;
+        console.log((a = --b + ((a = 0) !== typeof A), +void ((a >>= 0) && console.log("PASS"))));
+    }
+    expect_stdout: [
+        "PASS",
+        "NaN",
+    ]
+}
+
+issue_4047_2: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        sequences: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var b = 1;
+        console.log(+function(a) {
+            b = a;
+            (a >>= 0) && console.log("PASS");
+        }(--b + (0 !== typeof A)));
+    }
+    expect: {
+        var a;
+        console.log((a = +(0 !== typeof A), +void ((a >>= 0) && console.log("PASS"))));
+    }
+    expect_stdout: [
+        "PASS",
+        "NaN",
+    ]
+}
+
+issue_4051: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        try {
+            var a = (b = b.p, "FAIL"), b = b;
+        } catch (e) {}
+        console.log(a);
+    }
+    expect: {
+        try {
+            var a = (b = b.p, "FAIL"), b = b;
+        } catch (e) {}
+        console.log(a);
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4070: {
+    options = {
+        collapse_vars: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function f() {
+            function g() {}
+            g.p++;
+            return f.p = g.p;
+        }());
+    }
+    expect: {
+        console.log(function f() {
+            function g() {}
+            return f.p = ++g.p;
+        }());
+    }
+    expect_stdout: "NaN"
+}
+
+issue_4242: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            if (console)
+                var a = function(){}, b = (!1 === console || a)();
+        }());
+    }
+    expect: {
+        console.log(function() {
+            console && (!1 === console || function(){})();
+        }());
+    }
+    expect_stdout: "undefined"
+}

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 +72,27 @@ 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: Declarations in unreachable code! [test/compress/conditionals.js:4,12]",
+        "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: Declarations in unreachable code! [test/compress/conditionals.js:13,12]",
+        "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 +802,28 @@ 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 +1178,7 @@ issue_1645_2: {
     expect_stdout: true
 }
 
-condition_symbol_matches_consequent: {
+condition_matches_consequent: {
     options = {
         conditionals: true,
     }
@@ -1166,6 +1207,35 @@ 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,

test/compress/dead-code.js

@@ -59,6 +59,11 @@ dead_code_2_should_warn: {
         f();
     }
     expect_stdout: true
+    expect_warnings: [
+        "WARN: Dropping unreachable code [test/compress/dead-code.js:8,12]",
+        "WARN: Declarations in unreachable code! [test/compress/dead-code.js:10,16]",
+        "WARN: Dropping unreachable code [test/compress/dead-code.js:10,16]",
+    ]
     node_version: "<=4"
 }
 
@@ -89,11 +94,23 @@ 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: Declarations in unreachable code! [test/compress/dead-code.js:3,12]",
+        "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: Declarations in unreachable code! [test/compress/dead-code.js:9,12]",
+        "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"
 }
 
@@ -236,7 +253,7 @@ collapse_vars_lvalues_drop_assign: {
     }
 }
 
-collapse_vars_misc1: {
+collapse_vars_misc: {
     options = {
         collapse_vars: true,
         dead_code: true,
@@ -1151,3 +1168,214 @@ issue_3830_6: {
     }
     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"
+}

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");
             })();
         })();
@@ -2489,7 +2508,7 @@ drop_duplicated_var_catch: {
     }
 }
 
-issue_3802: {
+issue_3802_1: {
     options = {
         functions: true,
         reduce_vars: true,
@@ -2510,3 +2529,586 @@ issue_3802: {
     }
     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 +2207,843 @@ 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"
+}

test/compress/functions.js

@@ -1483,8 +1483,7 @@ issue_2663_2: {
     }
     expect: {
         (function() {
-            var i;
-            for (i in { a: 1, b: 2, c: 3 })
+            for (var i in { a: 1, b: 2, c: 3 })
                 j = i, console.log(j);
             var j;
         })();
@@ -2336,6 +2335,7 @@ issue_3274: {
         inline: true,
         join_vars: true,
         loops: true,
+        passes: 2,
         reduce_vars: true,
         unused: true,
     }
@@ -2676,7 +2676,7 @@ cross_references_3: {
                 };
                 return Math.square(n) + Math.cube(n);
             };
-        }(Math)(2));
+        }()(2));
         console.log(Math.square(3), Math.cube(3));
     }
     expect_stdout: [
@@ -3514,10 +3514,9 @@ hoisted_single_use: {
     }
     expect: {
         function f(a) {
-            for (var r in a) g(r);
-        }
-        function g(a) {
-            console.log(a);
+            for (var r in a) (function(a) {
+                console.log(a);
+            })(r);
         }
         (function(a) {
             var g = a.bar;
@@ -4660,3 +4659,459 @@ issue_3836: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3852: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            return function(b) {
+                return b && (b[0] = 0), "PASS";
+            }(a);
+        }(42));
+    }
+    expect: {
+        console.log(function(a) {
+            return a && (a[0] = 0), "PASS";
+        }(42));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3911: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            return function() {
+                if (a) (a++, b += a);
+                f();
+            };
+        }
+        var a = f, b;
+        console.log("PASS");
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3929: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var abc = function f() {
+                (function() {
+                    switch (f) {
+                    default:
+                        var abc = 0;
+                    case 0:
+                        abc.p;
+                    }
+                    console.log(typeof f);
+                })();
+            };
+            typeof abc && abc();
+        })();
+    }
+    expect: {
+        (function() {
+            var abc = function f() {
+                (function() {
+                    switch (f) {
+                    default:
+                        var abc = 0;
+                    case 0:
+                        abc.p;
+                    }
+                    console.log(typeof f);
+                })();
+            };
+            typeof abc && abc();
+        })();
+    }
+    expect_stdout: "function"
+}
+
+issue_4006: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        inline: true,
+        keep_fargs: "strict",
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        (function() {
+            (function(b, c) {
+                for (var k in console.log(c), 0)
+                    return b += 0;
+            })(0, --a);
+            return a ? 0 : --a;
+        })();
+    }
+    expect: {
+        var a = 0;
+        (function(c) {
+            for (var k in console.log(c), 0)
+                return;
+        })(--a), a || --a;
+    }
+    expect_stdout: "-1"
+}
+
+issue_4155: {
+    options = {
+        functions: true,
+        inline: true,
+        merge_vars: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var a;
+            (function() {
+                console.log(a);
+            })(a);
+            var b = function() {};
+            b && console.log(typeof b);
+        })();
+    }
+    expect: {
+        (function() {
+            void console.log(b);
+            var b = function() {};
+            b && console.log(typeof b);
+        })();
+    }
+    expect_stdout: [
+        "undefined",
+        "function",
+    ]
+}
+
+issue_4159: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 42, c = function(b) {
+            (b = a) && console.log(a++, b);
+        }(c = a);
+    }
+    expect: {
+        var a = 42;
+        (b = a) && console.log(a++, b);
+        var b;
+    }
+    expect_stdout: "42 42"
+}
+
+direct_inline: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f(a, b) {
+            function g(c) {
+                return c >> 1;
+            }
+            return g(a) + g(b);
+        }
+        console.log(f(13, 31));
+    }
+    expect: {
+        function f(a, b) {
+            return (a >> 1) + (b >> 1);
+        }
+        console.log(f(13, 31));
+    }
+    expect_stdout: "21"
+}
+
+direct_inline_catch_redefined: {
+    options = {
+        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_4171_1: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            try {
+                while (a)
+                    var e = function() {};
+            } catch (e) {
+                return function() {
+                    return e;
+                };
+            }
+        }(!console));
+    }
+    expect: {
+        console.log(function(a) {
+            try {
+                while (a)
+                    var e = function() {};
+            } catch (e) {
+                return function() {
+                    return e;
+                };
+            }
+        }(!console));
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4171_2: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            try {
+                while (a);
+            } catch (e) {
+                return function() {
+                    return e;
+                };
+            } finally {
+                var e = function() {};
+            }
+        }(!console));
+    }
+    expect: {
+        console.log(function(a) {
+            try {
+                while (a);
+            } catch (e) {
+                return function() {
+                    return e;
+                };
+            } finally {
+                function e() {}
+            }
+        }(!console));
+    }
+    expect_stdout: "undefined"
+}
+
+catch_defun: {
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        try {
+            throw 42;
+        } catch (a) {
+            function f() {
+                return typeof a;
+            }
+        }
+        console.log(f());
+    }
+    expect: {
+        try {
+            throw 42;
+        } catch (o) {
+            function t() {
+                return typeof o;
+            }
+        }
+        console.log(t());
+    }
+    expect_stdout: true
+}
+
+catch_no_argname: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        function f() {
+            return a;
+        }
+        try {
+            throw a;
+        } catch {
+            function g() {
+                return a;
+            }
+            console.log(a, f(), g());
+        }
+        console.log(a, f(), g());
+    }
+    expect: {
+        var a = "PASS";
+        try {
+            throw a;
+        } catch {
+            console.log(a, a, a);
+        }
+        console.log(a, a, a);
+    }
+    expect_stdout: [
+        "PASS PASS PASS",
+        "PASS PASS PASS",
+    ]
+    node_version: ">=10"
+}
+
+issue_4186: {
+    options = {
+        conditionals: true,
+        inline: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        sequences: true,
+        unused: true,
+    }
+    input: {
+        console.log(typeof function() {
+            return function() {
+                function f() {
+                    if (1)
+                        g();
+                    else
+                        (function() {
+                            return f;
+                        });
+                }
+                return f;
+                function g() {
+                    if (1) {
+                        if (0)
+                            h;
+                        else
+                            h();
+                        var key = 0;
+                    }
+                }
+                function h() {
+                    return factory;
+                }
+            };
+        }()());
+    }
+    expect: {
+        console.log(typeof function() {
+            return function f() {
+                1 ? void (1 && (0 ? h : h(), 0)) : function() {
+                    return f;
+                };
+            };
+            function h() {
+                return factory;
+            }
+        }());
+    }
+    expect_stdout: "function"
+}
+
+issue_4233: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            try {
+                var a = function() {};
+                try {
+                    throw 42;
+                } catch (a) {
+                    (function() {
+                        console.log(typeof a);
+                    })();
+                    var a;
+                }
+            } catch (e) {}
+        })();
+    }
+    expect: {
+        (function() {
+            try {
+                var a = function() {};
+                try {
+                    throw 42;
+                } catch (a) {
+                    (function() {
+                        console.log(typeof a);
+                    })();
+                    var a;
+                }
+            } catch (e) {}
+        })();
+    }
+    expect_stdout: "number"
+}

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

@@ -912,3 +912,132 @@ 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

@@ -2223,13 +2223,13 @@ 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 +2389,7 @@ issue_3703: {
         var a = "PASS";
         (function() {
             var b;
-            var c = function g() {
+            var c = function() {
                 a = "FAIL";
             };
             a ? b |= c : b.p;
@@ -2460,3 +2460,420 @@ issue_3825: {
     }
     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"
+}

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

@@ -90,13 +90,13 @@ non_hoisted_function_after_return_2a: {
         "WARN: Declarations 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: 36",
+        "INFO: pass 0: last_count: Infinity, count: 35",
         "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 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: 36, count: 18",
+        "INFO: pass 1: last_count: 35, count: 18",
     ]
 }
 
@@ -248,13 +248,13 @@ non_hoisted_function_after_return_2a_strict: {
         "WARN: Declarations 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: 47",
+        "INFO: pass 0: last_count: Infinity, count: 46",
         "WARN: Dropping unreachable code [test/compress/issue-1034.js:10,12]",
         "WARN: Declarations 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: 47, count: 29",
+        "INFO: pass 1: last_count: 46, count: 29",
     ]
 }
 

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-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/join_vars.js

@@ -277,8 +277,8 @@ join_object_assignments_forin: {
     }
     expect: {
         console.log(function() {
-            var o = { a: "PASS" };
-            for (var a in o)
+            var o = { a: "PASS" }, a;
+            for (a in o)
                 return o[a];
         }());
     }
@@ -785,11 +785,12 @@ issue_3791_2: {
 
 issue_3795: {
     options = {
+        booleans: true,
         collapse_vars: true,
-        conditionals: true,
         dead_code: true,
         evaluate: true,
         join_vars: true,
+        keep_fargs: "strict",
         loops: true,
         passes: 2,
         reduce_vars: true,
@@ -798,22 +799,21 @@ issue_3795: {
     }
     input: {
         var a = "FAIL";
-        function f(b) {
-            for (var i = 1; b && i; --i) return 0;
+        function f(b, c) {
+            for (var i = 5; c && i; --i) return -1;
             a = "PASS";
         }
-        var c = f(a = "");
-        console.log(a);
+        var d = f(a = 42, d);
+        console.log(a, d);
     }
     expect: {
-        var a = "FAIL";
-        (function(b) {
-            a = "";
+        var a = "FAIL", d = function() {
+            if (void 0) return -1;
             a = "PASS";
-        })();
-        console.log(a);
+        }(a = 42);
+        console.log(a, d);
     }
-    expect_stdout: "PASS"
+    expect_stdout: "PASS undefined"
 }
 
 if_body: {
@@ -989,3 +989,69 @@ conditional_assignments_3: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3856: {
+    options = {
+        booleans: true,
+        conditionals: true,
+        if_return: true,
+        join_vars: true,
+        sequences: true,
+    }
+    input: {
+        console.log(function() {
+            (function() {
+                var a;
+                if (!a) {
+                    a = 0;
+                    for (var b; !console;);
+                    return 0;
+                }
+                if (a) return 1;
+            })();
+        }());
+    }
+    expect: {
+        console.log(function() {
+            (function() {
+                var a, b;
+                if (a) return !!a;
+                for (a = 0; !console;);
+                return 0;
+            })();
+        }());
+    }
+    expect_stdout: "undefined"
+}
+
+issue_3916: {
+    options = {
+        join_vars: true,
+    }
+    input: {
+        var o = {};
+        o.p = "PASS";
+        o.__proto__ = 42;
+        o.q = "FAIL";
+        o.__proto__ = {
+            p: "FAIL",
+            q: "PASS",
+        };
+        o.__proto__ = "foo";
+        console.log(typeof o.__proto__, o.p, delete o.q, o.q);
+    }
+    expect: {
+        var o = {
+            p: "PASS",
+            __proto__: 42,
+            q: "FAIL",
+        };
+        o.__proto__ = {
+            p: "FAIL",
+            q: "PASS",
+        };
+        o.__proto__ = "foo";
+        console.log(typeof o.__proto__, o.p, delete o.q, o.q);
+    }
+    expect_stdout: "object PASS true PASS"
+}

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";

test/compress/let.js

@@ -0,0 +1,895 @@
+retain_block: {
+    options = {}
+    input: {
+        "use strict";
+        {
+            let a = "FAIL";
+        }
+        var a = "PASS";
+        console.log(a);
+    }
+    expect: {
+        "use strict";
+        {
+            let a = "FAIL";
+        }
+        var a = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+if_dead_branch: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+    }
+    input: {
+        "use strict";
+        console.log(function() {
+            if (0) {
+                let a = 0;
+            }
+            return typeof a;
+        }());
+    }
+    expect: {
+        "use strict";
+        console.log(function() {
+            0;
+            {
+                let a;
+            }
+            return typeof a;
+        }());
+    }
+    expect_stdout: "undefined"
+    node_version: ">=4"
+}
+
+merge_vars_1: {
+    options = {
+        merge_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        let a = console;
+        console.log(typeof a);
+        var b = typeof a;
+        console.log(b);
+    }
+    expect: {
+        "use strict";
+        let a = console;
+        console.log(typeof a);
+        var b = typeof a;
+        console.log(b);
+    }
+    expect_stdout: [
+        "object",
+        "object",
+    ]
+    node_version: ">=4"
+}
+
+merge_vars_2: {
+    options = {
+        inline: true,
+        merge_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        var a = 0;
+        (function() {
+            var b = function f() {
+                let c = a && f;
+                c.var += 0;
+            }();
+            console.log(b);
+        })(1 && --a);
+    }
+    expect: {
+        "use strict";
+        var a = 0;
+        1 && --a,
+        b = function f() {
+            let c = a && f;
+            c.var += 0;
+        }(),
+        void console.log(b);
+        var b;
+    }
+    expect_stdout: "undefined"
+    node_version: ">=4"
+}
+
+merge_vars_3: {
+    options = {
+        merge_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        {
+            let a = 0;
+            var b = console;
+            console.log(typeof b);
+        }
+        var a = 1;
+        console.log(typeof a);
+    }
+    expect: {
+        "use strict";
+        {
+            let a = 0;
+            var b = console;
+            console.log(typeof b);
+        }
+        var a = 1;
+        console.log(typeof a);
+    }
+    expect_stdout: [
+        "object",
+        "number",
+    ]
+    node_version: ">=4"
+}
+
+use_before_init_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        a = "foo";
+        let a = "bar";
+    }
+    expect: {
+        "use strict";
+        a = "foo";
+        let a = "bar";
+    }
+    expect_stdout: true
+    node_version: ">=4"
+}
+
+use_before_init_2: {
+    options = {
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            a = "foo";
+        } catch (e) {
+            console.log("PASS");
+        }
+        let a = "bar";
+    }
+    expect: {
+        "use strict";
+        try {
+            a = "foo";
+        } catch (e) {
+            console.log("PASS");
+        }
+        let a = "bar";
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+use_before_init_3: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        "use strict";
+        try {
+            a;
+        } catch (e) {
+            console.log("PASS");
+        }
+        let a = 42;
+    }
+    expect: {
+        "use strict";
+        try {
+            a;
+        } catch (e) {
+            console.log("PASS");
+        }
+        let a = 42;
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+use_before_init_4: {
+    options = {
+        reduce_vars: true,
+    }
+    input: {
+        "use strict";
+        try {
+            console.log(a);
+        } catch (e) {
+            console.log("PASS");
+        }
+        let a = "FAIL";
+    }
+    expect: {
+        "use strict";
+        try {
+            console.log(a);
+        } catch (e) {
+            console.log("PASS");
+        }
+        let a = "FAIL";
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+collapse_block: {
+    options = {
+        collapse_vars: true,
+        pure_getters: "strict",
+        unsafe: true,
+    }
+    input: {
+        "use strict";
+        {
+            let a = typeof console;
+            console.log(a);
+        }
+    }
+    expect: {
+        "use strict";
+        {
+            let a = typeof console;
+            console.log(a);
+        }
+    }
+    expect_stdout: "object"
+    node_version: ">=4"
+}
+
+reduce_block_1: {
+    options = {
+        reduce_vars: true,
+    }
+    input: {
+        "use strict";
+        {
+            let a = typeof console;
+            console.log(a);
+        }
+    }
+    expect: {
+        "use strict";
+        {
+            let a = typeof console;
+            console.log(a);
+        }
+    }
+    expect_stdout: "object"
+    node_version: ">=4"
+}
+
+reduce_block_2: {
+    options = {
+        reduce_vars: true,
+    }
+    input: {
+        "use strict";
+        {
+            let a = typeof console;
+            console.log(a);
+        }
+        console.log(typeof a);
+    }
+    expect: {
+        "use strict";
+        {
+            let a = typeof console;
+            console.log(a);
+        }
+        console.log(typeof a);
+    }
+    expect_stdout: [
+        "object",
+        "undefined",
+    ]
+    node_version: ">=4"
+}
+
+reduce_block_2_toplevel: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        {
+            let a = typeof console;
+            console.log(a);
+        }
+        console.log(typeof a);
+    }
+    expect: {
+        "use strict";
+        {
+            let a = typeof console;
+            console.log(a);
+        }
+        console.log(typeof a);
+    }
+    expect_stdout: [
+        "object",
+        "undefined",
+    ]
+    node_version: ">=4"
+}
+
+hoist_props: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+    }
+    input: {
+        "use strict";
+        {
+            let o = {
+                p: "PASS",
+            };
+            console.log(o.p);
+        }
+    }
+    expect: {
+        "use strict";
+        {
+            let o = {
+                p: "PASS",
+            };
+            console.log(o.p);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+loop_block_1: {
+    options = {
+        loops: true,
+    }
+    input: {
+        "use strict";
+        do {
+            let o = console;
+            console.log(typeof o.log);
+        } while (!console);
+    }
+    expect: {
+        "use strict";
+        do {
+            let o = console;
+            console.log(typeof o.log);
+        } while (!console);
+    }
+    expect_stdout: "function"
+    node_version: ">=4"
+}
+
+loop_block_2: {
+    options = {
+        loops: true,
+    }
+    input: {
+        "use strict";
+        do {
+            let o = {};
+            (function() {
+                console.log(typeof this, o.p++);
+            })();
+        } while (!console);
+    }
+    expect: {
+        "use strict";
+        do {
+            let o = {};
+            (function() {
+                console.log(typeof this, o.p++);
+            })();
+        } while (!console);
+    }
+    expect_stdout: "undefined NaN"
+    node_version: ">=4"
+}
+
+do_continue: {
+    options = {
+        loops: true,
+    }
+    input: {
+        "use strict";
+        try {
+            do {
+                {
+                    let a = 0;
+                    continue;
+                }
+            } while ([ A ]);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            do {
+                let a = 0;
+                continue;
+            } while ([ A ]);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+dead_block_after_return: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        "use strict";
+        (function(a) {
+            console.log(a);
+            return;
+            {
+                let a = "FAIL";
+            }
+        })("PASS");
+    }
+    expect: {
+        "use strict";
+        (function(a) {
+            console.log(a);
+            return;
+            {
+                let a;
+            }
+        })("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+do_if_continue_1: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        "use strict";
+        do {
+            if (console) {
+                console.log("PASS");
+                {
+                    let a = 0;
+                    var b;
+                    continue;
+                }
+            }
+        } while (b);
+    }
+    expect: {
+        "use strict";
+        do {
+            if (!console);
+            else {
+                console.log("PASS");
+                {
+                    let a = 0;
+                    var b;
+                }
+            }
+        } while (b);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+do_if_continue_2: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        "use strict";
+        do {
+            if (console) {
+                console.log("FAIL");
+                {
+                    let a = 0;
+                    A = 0;
+                    continue;
+                }
+            }
+        } while (A);
+    }
+    expect: {
+        "use strict";
+        do {
+            if (!console);
+            else {
+                console.log("FAIL");
+                {
+                    let a = 0;
+                    A = 0;
+                }
+            }
+        } while (A);
+    }
+    expect_stdout: ReferenceError("A is not defined")
+    node_version: ">=4"
+}
+
+drop_unused: {
+    options = {
+        evaluate: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        function f(a) {
+            let b = a, c = b;
+            0 && c.p++;
+        }
+        console.log(f());
+    }
+    expect: {
+        "use strict";
+        function f(a) {
+            let b = a;
+            b;
+        }
+        console.log(f());
+    }
+    expect_stdout: "undefined"
+    node_version: ">=4"
+}
+
+issue_4191: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        {
+            let a = function() {};
+        }
+        console.log(typeof a);
+    }
+    expect: {
+        "use strict";
+        {
+            let a = function() {};
+        }
+        console.log(typeof a);
+    }
+    expect_stdout: "undefined"
+    node_version: ">=4"
+}
+
+issue_4197: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        "use strict";
+        var a = 0;
+        try {
+            let b = function() {
+                a = 1;
+                b[1];
+            }();
+        } catch (e) {
+            console.log(a);
+        }
+    }
+    expect: {
+        "use strict";
+        var a = 0;
+        try {
+            let b = function() {
+                a = 1;
+                b[1];
+            }();
+        } catch (e) {
+            console.log(a);
+        }
+    }
+    expect_stdout: "1"
+    node_version: ">=4"
+}
+
+issue_4202: {
+    options = {
+        inline: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        {
+            let o = {};
+            (function() {
+                function f() {
+                    o.p = 42;
+                }
+                f(f);
+            })();
+            console.log(o.p++);
+        }
+    }
+    expect: {
+        "use strict";
+        {
+            let o = {};
+            (function() {
+                function f() {
+                    o.p = 42;
+                }
+                f(f);
+            })();
+            console.log(o.p++);
+        }
+    }
+    expect_stdout: "42"
+    node_version: ">=4"
+}
+
+issue_4207: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        {
+            let a = function() {};
+            console.log(a.length);
+        }
+    }
+    expect: {
+        "use strict";
+        {
+            let a = function() {};
+            console.log(a.length);
+        }
+    }
+    expect_stdout: "0"
+    node_version: ">=4"
+}
+
+issue_4218: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        var a;
+        {
+            let a = function() {};
+            var b = 0 * a;
+        }
+        console.log(typeof a, b);
+    }
+    expect: {
+        "use strict";
+        var b = 0 * function() {};
+        console.log(typeof void 0, b);
+    }
+    expect_stdout: "undefined NaN"
+    node_version: ">=4"
+}
+
+issue_4210: {
+    options = {
+        reduce_vars: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        var a;
+        (function() {
+            try {
+                throw 42;
+            } catch (e) {
+                let a = typeof e;
+                console.log(a);
+            } finally {
+                return a = "foo";
+            }
+        })();
+        console.log(typeof a);
+    }
+    expect: {
+        "use strict";
+        var a;
+        (function() {
+            try {
+                throw 42;
+            } catch (e) {
+                let a = typeof e;
+                console.log(a);
+            } finally {
+                return a = "foo";
+            }
+        })();
+        console.log(typeof a);
+    }
+    expect_stdout: [
+        "number",
+        "string",
+    ]
+    node_version: ">=4"
+}
+
+issue_4212_1: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        "use strict";
+        console.log({
+            get b() {
+                let a = 0;
+                return a /= 0;
+            }
+        }.b);
+    }
+    expect: {
+        "use strict";
+        console.log({
+            get b() {
+                let a = 0;
+                return a / 0;
+            }
+        }.b);
+    }
+    expect_stdout: "NaN"
+    node_version: ">=4"
+}
+
+issue_4212_2: {
+    options = {
+        reduce_vars: true,
+    }
+    input: {
+        "use strict";
+        console.log({
+            get b() {
+                let a = 0;
+                return a /= 0;
+            }
+        }.b);
+    }
+    expect: {
+        "use strict";
+        console.log({
+            get b() {
+                let a = 0;
+                return a /= 0;
+            }
+        }.b);
+    }
+    expect_stdout: "NaN"
+    node_version: ">=4"
+}
+
+skip_braces: {
+    beautify = {
+        beautify: true,
+        braces: true,
+    }
+    input: {
+        "use strict";
+        if (console)
+            let a = console.log(typeof a);
+    }
+    expect_exact: [
+        '"use strict";',
+        "",
+        "if (console) let a = console.log(typeof a);",
+    ]
+    expect_stdout: true
+    node_version: ">=4"
+}
+
+issue_4225: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        "use strict";
+        let a = void typeof b;
+        let b = 42;
+        console.log(a, b);
+    }
+    expect: {
+        "use strict";
+        let a = void b;
+        let b = 42;
+        console.log(a, b);
+    }
+    expect_stdout: true
+    node_version: ">=4"
+}
+
+issue_4229: {
+    options = {
+        ie8: true,
+        side_effects: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function f() {
+                f;
+                let f;
+            })();
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function f() {
+                f;
+                let f;
+            })();
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_4231: {
+    options = {
+        ie8: true,
+        side_effects: true,
+    }
+    input: {
+        "use strict";
+        typeof a == 0;
+        console.log(typeof function a() {
+            let a;
+        });
+    }
+    expect: {
+        "use strict";
+        console.log(typeof function a() {
+            let a;
+        });
+    }
+    expect_stdout: "function"
+    node_version: ">=4"
+}

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);
     }
@@ -756,7 +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]",
     ]
 }
 
@@ -933,3 +1001,256 @@ 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,
+        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"
+}

test/compress/numbers.js

@@ -91,7 +91,7 @@ evaluate_1: {
     expect: {
         console.log(
             x + 1 + 2,
-            2 * x,
+            2 * +x,
             +x + 1 + 2,
             1 + x + 2 + 3,
             3 | x,
@@ -130,7 +130,7 @@ evaluate_1_unsafe_math: {
     expect: {
         console.log(
             x + 1 + 2,
-            2 * x,
+            2 * +x,
             +x + 3,
             1 + x + 2 + 3,
             3 | x,
@@ -148,45 +148,52 @@ evaluate_1_unsafe_math: {
 evaluate_2: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: false,
     }
     input: {
-        var x = "42", y = null;
-        [
-            x + 1 + 2,
-            x * 1 * 2,
-            +x + 1 + 2,
-            1 + x + 2 + 3,
-            1 | x | 2 | 3,
-            1 + x-- + 2 + 3,
-            1 + (x*y + 2) + 3,
-            1 + (2 + x + 3),
-            1 + (2 + ~x + 3),
-            -y + (2 + ~x + 3),
-            1 & (2 & x & 3),
-            1 + (2 + (x |= 0) + 3),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var x = "" + num, y = null;
+            [
+                x + 1 + 2,
+                x * 1 * 2,
+                +x + 1 + 2,
+                1 + x + 2 + 3,
+                1 | x | 2 | 3,
+                1 + x-- + 2 + 3,
+                1 + (x*y + 2) + 3,
+                1 + (2 + x + 3),
+                1 + (2 + ~x + 3),
+                -y + (2 + ~x + 3),
+                1 & (2 & x & 3),
+                1 + (2 + (x |= 0) + 3),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect: {
-        var x = "42", y = null;
-        [
-            x + 1 + 2,
-            2 * x,
-            +x + 1 + 2,
-            1 + x + 2 + 3,
-            3 | x,
-            1 + x-- + 2 + 3,
-            x*y + 2 + 1 + 3,
-            1 + (2 + x + 3),
-            2 + ~x + 3 + 1,
-            2 + ~x + 3 - y,
-            0 & x,
-            2 + (x |= 0) + 3 + 1,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var x = "" + num, y = null;
+            [
+                x + "12",
+                2 * x,
+                +x + 1 + 2,
+                1 + x + "23",
+                3 | x,
+                1 + x-- + 2 + 3,
+                x*y + 2 + 1 + 3,
+                2 + x + 3 + 1,
+                2 + ~x + 3 + 1,
+                2 + ~x + 3,
+                0 & x,
+                2 + (x |= 0) + 3 + 1,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect_stdout: [
         "string 4212",
@@ -207,45 +214,52 @@ evaluate_2: {
 evaluate_2_unsafe_math: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: true,
     }
     input: {
-        var x = "42", y = null;
-        [
-            x + 1 + 2,
-            x * 1 * 2,
-            +x + 1 + 2,
-            1 + x + 2 + 3,
-            1 | x | 2 | 3,
-            1 + x-- + 2 + 3,
-            1 + (x*y + 2) + 3,
-            1 + (2 + x + 3),
-            1 + (2 + ~x + 3),
-            -y + (2 + ~x + 3),
-            1 & (2 & x & 3),
-            1 + (2 + (x |= 0) + 3),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var x = "" + num, y = null;
+            [
+                x + 1 + 2,
+                x * 1 * 2,
+                +x + 1 + 2,
+                1 + x + 2 + 3,
+                1 | x | 2 | 3,
+                1 + x-- + 2 + 3,
+                1 + (x*y + 2) + 3,
+                1 + (2 + x + 3),
+                1 + (2 + ~x + 3),
+                -y + (2 + ~x + 3),
+                1 & (2 & x & 3),
+                1 + (2 + (x |= 0) + 3),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect: {
-        var x = "42", y = null;
-        [
-            x + 1 + 2,
-            2 * x,
-            +x + 3,
-            1 + x + 2 + 3,
-            3 | x,
-            6 + x--,
-            x*y + 6,
-            1 + (2 + x + 3),
-            6 + ~x,
-            5 + ~x - y,
-            0 & x,
-            6 + (x |= 0),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var x = "" + num, y = null;
+            [
+                x + "12",
+                2 * x,
+                +x + 3,
+                1 + x + "23",
+                3 | x,
+                6 + x--,
+                x*y + 6,
+                6 + x,
+                6 + ~x,
+                5 + ~x,
+                0 & x,
+                6 + (x |= 0),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect_stdout: [
         "string 4212",
@@ -310,45 +324,52 @@ evaluate_4: {
 evaluate_5: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: false,
     }
     input: {
-        var a = "1";
-        [
-            +a + 2 + 3,
-            +a + 2 - 3,
-            +a - 2 + 3,
-            +a - 2 - 3,
-            2 + +a + 3,
-            2 + +a - 3,
-            2 - +a + 3,
-            2 - +a - 3,
-            2 + 3 + +a,
-            2 + 3 - +a,
-            2 - 3 + +a,
-            2 - 3 - +a,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var a = "" + num;
+            [
+                +a + 2 + 3,
+                +a + 2 - 3,
+                +a - 2 + 3,
+                +a - 2 - 3,
+                2 + +a + 3,
+                2 + +a - 3,
+                2 - +a + 3,
+                2 - +a - 3,
+                2 + 3 + +a,
+                2 + 3 - +a,
+                2 - 3 + +a,
+                2 - 3 - +a,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(1);
     }
     expect: {
-        var a = "1";
-        [
-            +a + 2 + 3,
-            +a + 2 - 3,
-            a - 2 + 3,
-            a - 2 - 3,
-            +a + 2 + 3,
-            +a + 2 - 3,
-            2 - a + 3,
-            2 - a - 3,
-            +a + 5,
-            5 - a,
-            +a - 1,
-            -1 - a,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var a = "" + num;
+            [
+                +a + 2 + 3,
+                +a + 2 - 3,
+                a - 2 + 3,
+                a - 2 - 3,
+                +a + 2 + 3,
+                +a + 2 - 3,
+                2 - a + 3,
+                2 - a - 3,
+                +a + 5,
+                5 - a,
+                +a - 1,
+                -1 - a,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(1);
     }
     expect_stdout: [
         "number 6",
@@ -369,45 +390,52 @@ evaluate_5: {
 evaluate_5_unsafe_math: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: true,
     }
     input: {
-        var a = "1";
-        [
-            +a + 2 + 3,
-            +a + 2 - 3,
-            +a - 2 + 3,
-            +a - 2 - 3,
-            2 + +a + 3,
-            2 + +a - 3,
-            2 - +a + 3,
-            2 - +a - 3,
-            2 + 3 + +a,
-            2 + 3 - +a,
-            2 - 3 + +a,
-            2 - 3 - +a,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var a = "" + num;
+            [
+                +a + 2 + 3,
+                +a + 2 - 3,
+                +a - 2 + 3,
+                +a - 2 - 3,
+                2 + +a + 3,
+                2 + +a - 3,
+                2 - +a + 3,
+                2 - +a - 3,
+                2 + 3 + +a,
+                2 + 3 - +a,
+                2 - 3 + +a,
+                2 - 3 - +a,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(1);
     }
     expect: {
-        var a = "1";
-        [
-            +a + 5,
-            +a + -1,
-            a - -1,
-            a - 5,
-            +a + 5,
-            +a + -1,
-            5 - a,
-            -1 - a,
-            +a + 5,
-            5 - a,
-            +a - 1,
-            -1 - a,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var a = "" + num;
+            [
+                +a + 5,
+                +a + -1,
+                a - -1,
+                a - 5,
+                +a + 5,
+                +a + -1,
+                5 - a,
+                -1 - a,
+                +a + 5,
+                5 - a,
+                +a - 1,
+                -1 - a,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(1);
     }
     expect_stdout: [
         "number 6",
@@ -546,37 +574,44 @@ evaluate_6_unsafe_math: {
 evaluate_7: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: false,
     }
     input: {
-        var x = "42", y;
-        [
-            +x + 2 + (3 + !y),
-            +x + 2 + (3 - !y),
-            +x + 2 - (3 + !y),
-            +x + 2 - (3 - !y),
-            +x - 2 + (3 + !y),
-            +x - 2 + (3 - !y),
-            +x - 2 - (3 + !y),
-            +x - 2 - (3 - !y),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num, y) {
+            var x = "" + num;
+            [
+                +x + 2 + (3 + !y),
+                +x + 2 + (3 - !y),
+                +x + 2 - (3 + !y),
+                +x + 2 - (3 - !y),
+                +x - 2 + (3 + !y),
+                +x - 2 + (3 - !y),
+                +x - 2 - (3 + !y),
+                +x - 2 - (3 - !y),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect: {
-        var x = "42", y;
-        [
-            +x + 2 + (3 + !y),
-            +x + 2 + (3 - !y),
-            +x + 2 - (3 + !y),
-            +x + 2 - (3 - !y),
-            x - 2 + (3 + !y),
-            x - 2 + (3 - !y),
-            x - 2 - (3 + !y),
-            x - 2 - (3 - !y),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num, y) {
+            var x = "" + num;
+            [
+                +x + 2 + (3 + !y),
+                +x + 2 + (3 - !y),
+                +x + 2 - (3 + !y),
+                +x + 2 - (3 - !y),
+                x - 2 + (3 + !y),
+                x - 2 + (3 - !y),
+                x - 2 - (3 + !y),
+                x - 2 - (3 - !y),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect_stdout: [
         "number 48",
@@ -593,37 +628,44 @@ evaluate_7: {
 evaluate_7_unsafe_math: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: true,
     }
     input: {
-        var x = "42", y;
-        [
-            +x + 2 + (3 + !y),
-            +x + 2 + (3 - !y),
-            +x + 2 - (3 + !y),
-            +x + 2 - (3 - !y),
-            +x - 2 + (3 + !y),
-            +x - 2 + (3 - !y),
-            +x - 2 - (3 + !y),
-            +x - 2 - (3 - !y),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num, y) {
+            var x = "" + num;
+            [
+                +x + 2 + (3 + !y),
+                +x + 2 + (3 - !y),
+                +x + 2 - (3 + !y),
+                +x + 2 - (3 - !y),
+                +x - 2 + (3 + !y),
+                +x - 2 + (3 - !y),
+                +x - 2 - (3 + !y),
+                +x - 2 - (3 - !y),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect: {
-        var x = "42", y;
-        [
-            +x + 5 + !y,
-            +x + 5 - !y,
-            +x + -1 - !y,
-            +x + -1 + !y,
-            x - -1 + !y,
-            x - -1 - !y,
-            x - 5 - !y,
-            x - 5 + !y,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num, y) {
+            var x = "" + num;
+            [
+                +x + 5 + !y,
+                +x + 5 - !y,
+                +x + -1 - !y,
+                +x + -1 + !y,
+                x - -1 + !y,
+                x - -1 - !y,
+                x - 5 - !y,
+                x - 5 + !y,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect_stdout: [
         "number 48",
@@ -637,6 +679,22 @@ 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 +1309,29 @@ 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/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: {

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

@@ -848,9 +848,8 @@ collapse_vars_1_true: {
     }
     expect: {
         function f(a, b) {
-            for (;;) {
+            for (;;)
                 if (a.g() || b.p) break;
-            }
         }
     }
 }

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 +299,137 @@ 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"
+}

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,
     }
@@ -898,15 +910,16 @@ issue_1758: {
 
 issue_2535: {
     options = {
+        conditionals: true,
         dead_code: true,
         evaluate: true,
         switches: true,
     }
     input: {
         switch(w(), 42) {
-            case 13: x();
-            case 42: y();
-            default: z();
+          case 13: x();
+          case 42: y();
+          default: z();
         }
     }
     expect: {
@@ -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/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 +1,236 @@
+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"
+}

test/input/invalid/switch.js

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

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-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

@@ -14,9 +14,9 @@ if (typeof phantom == "undefined") {
         args.splice(debug, 1);
         debug = true;
     }
-    args.unshift("bin/uglifyjs");
     if (!args.length) args.push("-mcb", "beautify=false,webkit");
-    args.push("--timings");
+    args.unshift("bin/uglifyjs");
+    args.push("--validate", "--timings");
     var child_process = require("child_process");
     var fetch = require("./fetch");
     var http = require("http");
@@ -60,7 +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",
@@ -71,7 +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);
@@ -82,7 +85,7 @@ if (typeof phantom == "undefined") {
                     process.exit(0);
                 });
             });
-        }
+        })();
     });
     server.timeout = 0;
 } else {

test/mocha/cli.js

@@ -249,7 +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"));
@@ -257,7 +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");
@@ -330,7 +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/);
@@ -342,7 +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/);
@@ -354,7 +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/);
@@ -366,7 +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/);
@@ -378,7 +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, "");
@@ -392,7 +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, "");
@@ -406,7 +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, "");
@@ -420,7 +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, "");
@@ -434,7 +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, "");
@@ -448,7 +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, "");
@@ -462,7 +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, "");
@@ -476,7 +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, "");
@@ -490,7 +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, "");
@@ -504,7 +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, "");
@@ -518,7 +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, "");
@@ -532,7 +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, "");
@@ -546,7 +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, "");
@@ -560,7 +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, "");
@@ -574,7 +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, "");
@@ -588,7 +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, "");
@@ -602,7 +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, "");
@@ -616,7 +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, "");
@@ -629,6 +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,
@@ -717,7 +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/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,
@@ -296,4 +299,18 @@ describe("test/reduce.js", function() {
             "// }",
         ]).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/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) {
-            return e instanceof UglifyJS.JS_Parse_Error
-                && e.message === "Unterminated string constant";
-        };
-
-        for (var input in inputs) {
-            assert.throws(test(inputs[input]), error);
-        }
+            }, function(e) {
+                return e instanceof UglifyJS.JS_Parse_Error
+                    && e.message === "Unterminated string constant";
+            });
+        });
+    });
+    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) {
-            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);
-        }
+            }, function(e) {
+                return e instanceof UglifyJS.JS_Parse_Error
+                    && e.message === "Legacy octal escape sequences are not allowed in strict mode";
+            });
+        });
     });
-
     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/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

@@ -4,20 +4,19 @@ 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 || {};
@@ -31,12 +30,17 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
     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) {
         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
         return {
@@ -108,19 +112,18 @@ 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
+            // ignore lvalues
+            if (parent instanceof U.AST_Assign && parent.left === 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
 
@@ -142,7 +145,9 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 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);
@@ -407,7 +412,7 @@ 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: {},
@@ -424,7 +429,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     if (node.TYPE == "Call" && node.expression.print_to_string() == "console.log") {
                         return to_sequence(node.args);
                     }
-                    if (node instanceof U.AST_Catch) {
+                    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)),
@@ -434,7 +439,8 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     }
                 }));
                 var code = testcase_ast.print_to_string();
-                if (diff = producesDifferentResultWhenMinified(result_cache, code, minify_options, max_timeout)) {
+                var diff = test_for_diff(code, minify_options, result_cache, max_timeout);
+                if (diff && !diff.timed_out && !diff.error) {
                     testcase = code;
                     differs = diff;
                 } else {
@@ -447,6 +453,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 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 && pass == 1 && c % 25 == 0) {
                     log("// reduce test pass " + pass + ", iteration " + c + ": " + testcase.length + " bytes");
@@ -464,7 +471,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     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.
@@ -489,26 +496,49 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     }
                 }
             }
-            if (c == 0) break;
+            if (before_iterations === testcase) break;
             if (verbose) {
                 log("// reduce test pass " + pass + ": " + testcase.length + " bytes");
             }
         }
-        testcase = try_beautify(result_cache, testcase, minify_options, differs.unminified_result, max_timeout);
+        var beautified = U.minify(testcase, {
+            compress: false,
+            mangle: false,
+            output: {
+                beautify: true,
+                braces: true,
+                comments: true,
+            },
+        });
+        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;
+            }
+        }
         var lines = [ "" ];
-        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)) {
-            lines.push(
-                "// (stringified)",
-                "// output: " + JSON.stringify(unminified_result),
-                "// minify: " + JSON.stringify(minified_result)
-            );
+        if (isNaN(max_timeout)) {
+            lines.push("// minify error: " + to_comment(strip_color_codes(differs.minified_result.stack)));
         } else {
-            lines.push(
-                "// output: " + to_comment(unminified_result),
-                "// minify: " + to_comment(minified_result)
-            );
+            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)) {
+                lines.push(
+                    "// (stringified)",
+                    "// output: " + JSON.stringify(unminified_result),
+                    "// minify: " + JSON.stringify(minified_result)
+                );
+            } else {
+                lines.push(
+                    "// output: " + to_comment(unminified_result),
+                    "// minify: " + to_comment(minified_result)
+                );
+            }
         }
         lines.push("// options: " + to_comment(minify_options_json));
         testcase.code += lines.join("\n");
@@ -529,28 +559,6 @@ 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) {
@@ -633,31 +641,43 @@ function wrap_with_console_log(node) {
     });
 }
 
-function run_code(result_cache, code, toplevel, timeout) {
+function run_code(code, toplevel, result_cache, timeout) {
     var key = crypto.createHash("sha1").update(code).digest("base64");
-    return result_cache[key] || (result_cache[key] = sandbox.run_code(code, toplevel, timeout));
+    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 producesDifferentResultWhenMinified(result_cache, code, minify_options, max_timeout) {
+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

@@ -9,6 +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

@@ -40,7 +40,7 @@ function createContext() {
             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/index.js

@@ -168,7 +168,7 @@ var VALUES = [
     "this",
 ];
 
-var BINARY_OPS_NO_COMMA = [
+var BINARY_OPS = [
     " + ", // spaces needed to disambiguate with ++ cases (could otherwise cause syntax errors)
     " - ",
     "/",
@@ -190,9 +190,15 @@ var BINARY_OPS_NO_COMMA = [
     "%",
     "&&",
     "||",
-    "^" ];
-
-var BINARY_OPS = [","].concat(BINARY_OPS_NO_COMMA);
+    "^",
+    ",",
+];
+BINARY_OPS = BINARY_OPS.concat(BINARY_OPS);
+BINARY_OPS = BINARY_OPS.concat(BINARY_OPS);
+BINARY_OPS = BINARY_OPS.concat(BINARY_OPS);
+BINARY_OPS = BINARY_OPS.concat(BINARY_OPS);
+BINARY_OPS = BINARY_OPS.concat(BINARY_OPS);
+BINARY_OPS.push(" in ");
 
 var ASSIGNMENTS = [
     "=",
@@ -269,6 +275,7 @@ var CANNOT_RETURN = true;
 var NO_DEFUN = false;
 var DEFUN_OK = true;
 var DONT_STORE = true;
+var NO_CONST = true;
 
 var VAR_NAMES = [
     "a",
@@ -306,6 +313,7 @@ var TYPEOF_OUTCOMES = [
     "crap",
 ];
 
+var block_vars = [];
 var unique_vars = [];
 var loops = 0;
 var funcs = 0;
@@ -323,6 +331,7 @@ function strictMode() {
 
 function createTopLevelCode() {
     VAR_NAMES.length = INITIAL_NAMES_LEN; // prune any previous names still in the list
+    block_vars.length = 0;
     unique_vars.length = 0;
     loops = 0;
     funcs = 0;
@@ -368,33 +377,77 @@ function filterDirective(s) {
     return s;
 }
 
+function createBlockVariables(recurmax, stmtDepth, canThrow, fn) {
+    var block_len = block_vars.length;
+    var var_len = VAR_NAMES.length;
+    var consts = [];
+    var lets = [];
+    unique_vars.push("a", "b", "c", "undefined", "NaN", "Infinity");
+    while (!rng(block_vars.length > block_len ? 10 : 100)) {
+        var name = createVarName(MANDATORY, DONT_STORE);
+        if (rng(2)) {
+            consts.push(name);
+        } else {
+            lets.push(name);
+        }
+        block_vars.push(name);
+    }
+    unique_vars.length -= 6;
+    fn(function() {
+        if (rng(2)) {
+            return createDefinitions("const", consts) + "\n" + createDefinitions("let", lets) + "\n";
+        } else {
+            return createDefinitions("let", lets) + "\n" + createDefinitions("const", consts) + "\n";
+        }
+    });
+    block_vars.length = block_len;
+    if (consts.length || lets.length) VAR_NAMES.splice(var_len, consts.length + lets.length);
+
+    function createDefinitions(type, names) {
+        if (!names.length) return "";
+        var save = VAR_NAMES;
+        VAR_NAMES = VAR_NAMES.filter(function(name) {
+            return names.indexOf(name) < 0;
+        });
+        var len = VAR_NAMES.length;
+        var s = type + " " + names.map(function(name) {
+            var value = createExpression(recurmax, NO_COMMA, stmtDepth, canThrow);
+            VAR_NAMES.push(name);
+            return name + " = " + value;
+        }).join(", ") + ";";
+        VAR_NAMES = save.concat(VAR_NAMES.slice(len));
+        return s;
+    }
+}
+
 function createFunction(recurmax, allowDefun, canThrow, stmtDepth) {
     if (--recurmax < 0) { return ";"; }
     if (!STMT_COUNT_FROM_GLOBAL) stmtDepth = 0;
-    var namesLenBefore = VAR_NAMES.length;
+    var s = [];
     var name;
-    if (allowDefun || rng(5) > 0) {
-        name = "f" + funcs++;
-    } else {
-        unique_vars.push("a", "b", "c");
-        name = createVarName(MANDATORY, !allowDefun);
-        unique_vars.length -= 3;
-    }
-    var s = [
-        "function " + name + "(" + createParams() + "){",
-        strictMode()
-    ];
-    if (rng(5) === 0) {
-        // functions with functions. lower the recursion to prevent a mess.
-        s.push(createFunctions(rng(5) + 1, Math.ceil(recurmax * 0.7), DEFUN_OK, canThrow, stmtDepth));
-    } else {
-        // functions with statements
-        s.push(createStatements(3, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth));
-    }
-    s.push("}", "");
-    s = filterDirective(s).join("\n");
+    createBlockVariables(recurmax, stmtDepth, canThrow, function(defns) {
+        var namesLenBefore = VAR_NAMES.length;
+        if (allowDefun || rng(5) > 0) {
+            name = "f" + funcs++;
+        } else {
+            unique_vars.push("a", "b", "c");
+            name = createVarName(MANDATORY, !allowDefun);
+            unique_vars.length -= 3;
+        }
+        s.push("function " + name + "(" + createParams() + "){", strictMode());
+        s.push(defns());
+        if (rng(5) === 0) {
+            // functions with functions. lower the recursion to prevent a mess.
+            s.push(createFunctions(rng(5) + 1, Math.ceil(recurmax * 0.7), DEFUN_OK, canThrow, stmtDepth));
+        } else {
+            // functions with statements
+            s.push(_createStatements(3, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth));
+        }
+        s.push("}", "");
+        s = filterDirective(s).join("\n");
 
-    VAR_NAMES.length = namesLenBefore;
+        VAR_NAMES.length = namesLenBefore;
+    });
 
     if (!allowDefun) {
         // avoid "function statements" (decl inside statements)
@@ -408,7 +461,7 @@ function createFunction(recurmax, allowDefun, canThrow, stmtDepth) {
     return s + ";";
 }
 
-function createStatements(n, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) {
+function _createStatements(n, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) {
     if (--recurmax < 0) { return ";"; }
     var s = "";
     while (--n > 0) {
@@ -417,6 +470,15 @@ function createStatements(n, recurmax, canThrow, canBreak, canContinue, cannotRe
     return s;
 }
 
+function createStatements(n, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) {
+    var s = "";
+    createBlockVariables(recurmax, stmtDepth, canThrow, function(defns) {
+        s += defns() + "\n";
+        s += _createStatements(n, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth);
+    });
+    return s;
+}
+
 function enableLoopControl(flag, defaultValue) {
     return Array.isArray(flag) && flag.indexOf("") < 0 ? flag.concat("") : flag || defaultValue;
 }
@@ -490,11 +552,16 @@ function createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn
         var label = createLabel(canBreak, canContinue);
         canBreak = label.break || enableLoopControl(canBreak, CAN_BREAK);
         canContinue = label.continue || enableLoopControl(canContinue, CAN_CONTINUE);
-        var optElementVar = "";
-        if (rng(5) > 1) {
-            optElementVar = "c = 1 + c; var " + createVarName(MANDATORY) + " = expr" + loop + "[key" + loop + "]; ";
-        }
-        return "{var expr" + loop + " = " + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "; " + label.target + " for (var key" + loop + " in expr" + loop + ") {" + optElementVar + createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + "}}";
+        var key = rng(10) ? "key" + loop : getVarName(NO_CONST);
+        return [
+            "{var expr" + loop + " = " + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "; ",
+            label.target + " for (",
+            /^key/.test(key) ? "var " : "",
+            key + " in expr" + loop + ") {",
+            rng(5) > 1 ? "c = 1 + c; var " + createVarName(MANDATORY) + " = expr" + loop + "[" + key + "]; " : "",
+            createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth),
+            "}}",
+        ].join("");
       case STMT_SEMI:
         return use_strict && rng(20) === 0 ? '"use strict";' : ";";
       case STMT_EXPR:
@@ -560,13 +627,18 @@ function createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn
             // the catch var should only be accessible in the catch clause...
             // we have to do go through some trouble here to prevent leaking it
             var nameLenBefore = VAR_NAMES.length;
-            var catchName = createVarName(MANDATORY);
-            var freshCatchName = VAR_NAMES.length !== nameLenBefore;
-            if (!catch_redef) unique_vars.push(catchName);
-            s += " catch (" + catchName + ") { " + createStatements(3, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + " }";
-            // remove catch name
-            if (!catch_redef) unique_vars.pop();
-            if (freshCatchName) VAR_NAMES.splice(nameLenBefore, 1);
+            createBlockVariables(recurmax, stmtDepth, canThrow, function(defns) {
+                var catchName = createVarName(MANDATORY);
+                var freshCatchName = VAR_NAMES.length !== nameLenBefore;
+                if (!catch_redef) unique_vars.push(catchName);
+                s += " catch (" + catchName + ") { ";
+                s += defns() + "\n";
+                s += _createStatements(3, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth);
+                s += " }";
+                // remove catch name
+                if (!catch_redef) unique_vars.pop();
+                if (freshCatchName) VAR_NAMES.splice(nameLenBefore, 1);
+            });
         }
         if (n !== 0) s += " finally { " + createStatements(3, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + " }";
         return s;
@@ -586,7 +658,7 @@ function createSwitchParts(recurmax, n, canThrow, canBreak, canContinue, cannotR
         if (hadDefault || rng(5) > 0) {
             s.push(
                 "case " + createExpression(recurmax, NO_COMMA, stmtDepth, canThrow) + ":",
-                createStatements(rng(3) + 1, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth),
+                _createStatements(rng(3) + 1, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth),
                 rng(10) > 0 ? " break;" : "/* fall-through */",
                 ""
             );
@@ -594,7 +666,7 @@ function createSwitchParts(recurmax, n, canThrow, canBreak, canContinue, cannotR
             hadDefault = true;
             s.push(
                 "default:",
-                createStatements(rng(3) + 1, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth),
+                _createStatements(rng(3) + 1, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth),
                 ""
             );
         }
@@ -642,7 +714,7 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
       case p++:
         return getVarName();
       case p++:
-        return getVarName() + createAssignment() + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow);
+        return getVarName(NO_CONST) + createAssignment() + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow);
       case p++:
         return createExpression(recurmax, COMMA_OK, stmtDepth, canThrow);
       case p++:
@@ -688,19 +760,22 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
             );
             break;
           default:
-            var instantiate = rng(4) ? "new " : "";
-            s.push(
-                instantiate + "function " + name + "(){",
-                strictMode()
-            );
-            if (instantiate) for (var i = rng(4); --i >= 0;) {
-                if (rng(2)) s.push("this." + getDotKey(true) + createAssignment() + _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ";");
-                else  s.push("this[" + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "]" + createAssignment() + _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ";");
-            }
-            s.push(
-                createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
-                rng(2) == 0 ? "}" : "}()"
-            );
+            createBlockVariables(recurmax, stmtDepth, canThrow, function(defns) {
+                var instantiate = rng(4) ? "new " : "";
+                s.push(
+                    instantiate + "function " + name + "(){",
+                    strictMode(),
+                    defns()
+                );
+                if (instantiate) for (var i = rng(4); --i >= 0;) {
+                    if (rng(2)) s.push("this." + getDotKey(true) + createAssignment() + _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ";");
+                    else  s.push("this[" + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "]" + createAssignment() + _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ";");
+                }
+                s.push(
+                    _createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
+                    rng(2) == 0 ? "}" : "}()"
+                );
+            });
             break;
         }
         VAR_NAMES.length = nameLenBefore;
@@ -762,6 +837,10 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
         return createArrayLiteral(recurmax, stmtDepth, canThrow) + "." + getDotKey();
       case p++:
         return createObjectLiteral(recurmax, stmtDepth, canThrow) + "." + getDotKey();
+      case p++:
+        return createValue() + " in " + createArrayLiteral(recurmax, stmtDepth, canThrow);
+      case p++:
+        return createValue() + " in " + createObjectLiteral(recurmax, stmtDepth, canThrow);
       case p++:
         var name = getVarName();
         var s = name + "[" + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "]";
@@ -832,28 +911,32 @@ function getDotKey(assign) {
 function createAccessor(recurmax, stmtDepth, canThrow) {
     var namesLenBefore = VAR_NAMES.length;
     var s;
-    var prop1 = getDotKey();
-    if (rng(2) == 0) {
-        s = [
-            "get " + prop1 + "(){",
-            strictMode(),
-            createStatements(2, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
-            createStatement(recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth, STMT_RETURN_ETC),
-            "},"
-        ];
-    } else {
-        var prop2;
-        do {
-            prop2 = getDotKey();
-        } while (prop1 == prop2);
-        s = [
-            "set " + prop1 + "(" + createVarName(MANDATORY) + "){",
-            strictMode(),
-            createStatements(2, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
-            "this." + prop2 + createAssignment() + _createBinaryExpr(recurmax, COMMA_OK, stmtDepth, canThrow) + ";",
-            "},"
-        ];
-    }
+    createBlockVariables(recurmax, stmtDepth, canThrow, function(defns) {
+        var prop1 = getDotKey();
+        if (rng(2) == 0) {
+            s = [
+                "get " + prop1 + "(){",
+                strictMode(),
+                defns(),
+                _createStatements(2, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
+                createStatement(recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth, STMT_RETURN_ETC),
+                "},"
+            ];
+        } else {
+            var prop2;
+            do {
+                prop2 = getDotKey();
+            } while (prop1 == prop2);
+            s = [
+                "set " + prop1 + "(" + createVarName(MANDATORY) + "){",
+                strictMode(),
+                defns(),
+                _createStatements(2, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
+                "this." + prop2 + createAssignment() + _createBinaryExpr(recurmax, COMMA_OK, stmtDepth, canThrow) + ";",
+                "},"
+            ];
+        }
+    });
     VAR_NAMES.length = namesLenBefore;
     return filterDirective(s).join("\n");
 }
@@ -879,7 +962,7 @@ function createNestedBinaryExpr(recurmax, noComma, stmtDepth, canThrow) {
 }
 function _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) {
     return "(" + _createSimpleBinaryExpr(recurmax, noComma, stmtDepth, canThrow)
-        + createBinaryOp(noComma) + _createSimpleBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ")";
+        + createBinaryOp(noComma, canThrow) + _createSimpleBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ")";
 }
 function _createSimpleBinaryExpr(recurmax, noComma, stmtDepth, canThrow) {
     // intentionally generate more hardcore ops
@@ -891,7 +974,7 @@ function _createSimpleBinaryExpr(recurmax, noComma, stmtDepth, canThrow) {
       case 1:
         return "(" + createUnarySafePrefix() + "(" + _createSimpleBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + "))";
       case 2:
-        assignee = getVarName();
+        assignee = getVarName(NO_CONST);
         return "(" + assignee + createAssignment() + _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ")";
       case 3:
         assignee = getVarName();
@@ -929,9 +1012,12 @@ function createValue() {
     return VALUES[rng(VALUES.length)];
 }
 
-function createBinaryOp(noComma) {
-    if (noComma) return BINARY_OPS_NO_COMMA[rng(BINARY_OPS_NO_COMMA.length)];
-    return BINARY_OPS[rng(BINARY_OPS.length)];
+function createBinaryOp(noComma, canThrow) {
+    var op;
+    do {
+        op = BINARY_OPS[rng(BINARY_OPS.length)];
+    } while (noComma && op == "," || !canThrow && op == " in ");
+    return op;
 }
 
 function createAssignment() {
@@ -950,9 +1036,10 @@ function createUnaryPostfix() {
     return UNARY_POSTFIX[rng(UNARY_POSTFIX.length)];
 }
 
-function getVarName() {
+function getVarName(noConst) {
     // try to get a generated name reachable from current scope. default to just `a`
-    return VAR_NAMES[INITIAL_NAMES_LEN + rng(VAR_NAMES.length - INITIAL_NAMES_LEN)] || "a";
+    var name = VAR_NAMES[INITIAL_NAMES_LEN + rng(VAR_NAMES.length - INITIAL_NAMES_LEN)];
+    return !name || noConst && block_vars.indexOf(name) >= 0 ? "a" : name;
 }
 
 function createVarName(maybe, dontStore) {
@@ -962,7 +1049,7 @@ function createVarName(maybe, dontStore) {
         do {
             name = VAR_NAMES[rng(VAR_NAMES.length)];
             if (suffix) name += "_" + suffix;
-        } while (unique_vars.indexOf(name) >= 0);
+        } while (unique_vars.indexOf(name) >= 0 || block_vars.indexOf(name) >= 0);
         if (suffix && !dontStore) VAR_NAMES.push(name);
         return name;
     }
@@ -1018,19 +1105,23 @@ function log_suspects(minify_options, component) {
     if (!options) return;
     if (typeof options != "object") options = {};
     var defs = default_options[component];
+    var toplevel = sandbox.has_toplevel(minify_options);
     var suspects = Object.keys(defs).filter(function(name) {
         var flip = name == "keep_fargs";
-        if (flip === !(name in options ? options : defs)[name]) {
+        if (flip !== (name in options ? options : defs)[name]) {
             var m = JSON.parse(JSON.stringify(minify_options));
             var o = JSON.parse(JSON.stringify(options));
             o[name] = flip;
             m[component] = o;
+            m.validate = true;
             var result = UglifyJS.minify(original_code, m);
-            if (result.error) {
+            if (typeof uglify_code != "string") {
+                return !sandbox.same_stdout(uglify_code, result.error);
+            } else if (result.error) {
                 errorln("Error testing options." + component + "." + name);
                 errorln(result.error);
             } else {
-                var r = sandbox.run_code(result.code, sandbox.has_toplevel(m));
+                var r = sandbox.run_code(result.code, toplevel);
                 return !sandbox.same_stdout(uglify_result, r);
             }
         }
@@ -1044,18 +1135,21 @@ function log_suspects(minify_options, component) {
     }
 }
 
-function log_suspects_global(options) {
+function log_suspects_global(options, toplevel) {
     var suspects = Object.keys(default_options).filter(function(component) {
       return typeof default_options[component] != "object";
     }).filter(function(component) {
         var m = JSON.parse(options);
         m[component] = false;
+        m.validate = true;
         var result = UglifyJS.minify(original_code, m);
-        if (result.error) {
+        if (typeof uglify_code != "string") {
+            return !sandbox.same_stdout(uglify_code, result.error);
+        } else if (result.error) {
             errorln("Error testing options." + component);
             errorln(result.error);
         } else {
-            var r = sandbox.run_code(result.code, sandbox.has_toplevel(m));
+            var r = sandbox.run_code(result.code, toplevel);
             return !sandbox.same_stdout(uglify_result, r);
         }
     });
@@ -1074,7 +1168,37 @@ function log(options) {
     errorln("//=============================================================");
     if (!ok) errorln("// !!!!!! Failed... round " + round);
     errorln("// original code");
-    try_beautify(original_code, toplevel, original_result, errorln);
+    var beautified = UglifyJS.minify(original_code, {
+        compress: false,
+        mangle: false,
+        output: {
+            beautify: true,
+            braces: true,
+        },
+    });
+    if (beautified.error) {
+        errorln("// !!! beautify failed !!!");
+        errorln(beautified.error);
+        errorln("//");
+        errorln(original_code);
+    } else {
+        var uglified = UglifyJS.minify(beautified.code, JSON.parse(options));
+        var expected, actual;
+        if (typeof uglify_code != "string" || uglified.error) {
+            expected = uglify_code;
+            actual = uglified.error;
+        } else {
+            expected = uglify_result;
+            actual = sandbox.run_code(uglified.code, toplevel);
+        }
+        if (sandbox.same_stdout(expected, actual)) {
+            errorln("// (beautified)");
+            errorln(beautified.code);
+        } else {
+            errorln("//");
+            errorln(original_code);
+        }
+    }
     errorln();
     errorln();
     errorln("//-------------------------------------------------------------");
@@ -1087,18 +1211,6 @@ function log(options) {
         errorln(original_result);
         errorln("uglified result:");
         errorln(uglify_result);
-        errorln("//-------------------------------------------------------------");
-        var reduced = reduce_test(original_code, JSON.parse(options), {
-            verbose: false,
-        }).code;
-        if (reduced) {
-            errorln();
-            errorln("// reduced test case (output will differ)");
-            errorln();
-            errorln(reduced);
-            errorln();
-            errorln("//-------------------------------------------------------------");
-        }
     } else {
         errorln("// !!! uglify failed !!!");
         errorln(uglify_code);
@@ -1109,19 +1221,38 @@ function log(options) {
             errorln(original_result);
         }
     }
+    errorln("//-------------------------------------------------------------");
+    var reduce_options = JSON.parse(options);
+    reduce_options.validate = true;
+    var reduced = reduce_test(original_code, reduce_options, {
+        verbose: false,
+    }).code;
+    if (reduced) {
+        errorln();
+        errorln("// reduced test case (output will differ)");
+        errorln();
+        errorln(reduced);
+        errorln();
+        errorln("//-------------------------------------------------------------");
+    }
     errorln("minify(options):");
     errorln(JSON.stringify(JSON.parse(options), null, 2));
     errorln();
-    if (!ok && typeof uglify_code == "string") {
+    if (!ok) {
         Object.keys(default_options).filter(function(component) {
           var defs = default_options[component];
           return defs && typeof defs == "object";
         }).forEach(log_suspects.bind(null, JSON.parse(options)));
-        log_suspects_global(options);
+        log_suspects_global(options, toplevel);
         errorln("!!!!!! Failed... round " + round);
     }
 }
 
+function sort_globals(code) {
+    var globals = sandbox.run_code("throw Object.keys(this).sort();" + code);
+    return globals.length ? "var " + globals.join(",") + ";" + code : code;
+}
+
 function fuzzy_match(original, uglified) {
     uglified = uglified.split(" ");
     var i = uglified.length;
@@ -1136,10 +1267,66 @@ function fuzzy_match(original, uglified) {
     return true;
 }
 
-var fallback_options = [ JSON.stringify({
-    compress: false,
-    mangle: false
-}) ];
+function patch_try_catch(orig, toplevel) {
+    var stack = [ {
+        code: orig,
+        index: 0,
+        offset: 0,
+        tries: [],
+    } ];
+    var re = /(?:(?:^|[\s{}):;])try|}\s*catch\s*\(([^)]+)\)|}\s*finally)\s*(?={)/g;
+    while (stack.length) {
+        var code = stack[0].code;
+        var offset = stack[0].offset;
+        var tries = stack[0].tries;
+        var match;
+        re.lastIndex = stack.shift().index;
+        while (match = re.exec(code)) {
+            var index = match.index + match[0].length + 1;
+            if (/(?:^|[\s{}):;])try\s*$/.test(match[0])) {
+                tries.unshift({ try: index - offset });
+                continue;
+            }
+            var insert;
+            if (/}\s*finally\s*$/.test(match[0])) {
+                tries.shift();
+                insert = 'if (typeof UFUZZ_ERROR == "object") throw UFUZZ_ERROR;';
+            } else {
+                while (tries.length && tries[0].catch) tries.shift();
+                tries[0].catch = index - offset;
+                insert = [
+                    "if (!" + match[1] + ".ufuzz_var) {",
+                        match[1] + '.ufuzz_var = "' + match[1] + '";',
+                        match[1] + ".ufuzz_try = " + tries[0].try + ";",
+                        match[1] + ".ufuzz_catch = " + tries[0].catch + ";",
+                        "UFUZZ_ERROR = " + match[1] + ";",
+                    "}",
+                    "throw " + match[1] + ";",
+                ].join("\n");
+            }
+            var new_code = code.slice(0, index) + insert + code.slice(index);
+            var result = sandbox.run_code(new_code, toplevel);
+            if (typeof result != "object" || typeof result.name != "string" || typeof result.message != "string") {
+                if (!stack.filled && match[1]) stack.push({
+                    code: code,
+                    index: index && index - 1,
+                    offset: offset,
+                    tries: JSON.parse(JSON.stringify(tries)),
+                });
+                offset += insert.length;
+                code = new_code;
+            } else if (result.name == "TypeError" && /'in'/.test(result.message)) {
+                index = result.ufuzz_catch;
+                return orig.slice(0, index) + result.ufuzz_var + ' = new Error("invalid `in`");' + orig.slice(index);
+            } else if (result.name == "RangeError" && result.message == "Maximum call stack size exceeded") {
+                index = result.ufuzz_try;
+                return orig.slice(0, index) + 'throw new Error("skipping infinite recursion");' + orig.slice(index);
+            }
+        }
+        stack.filled = true;
+    }
+}
+
 var minify_options = require("./options.json").map(JSON.stringify);
 var original_code, original_result, errored;
 var uglify_code, uglify_result, ok;
@@ -1147,42 +1334,56 @@ for (var round = 1; round <= num_iterations; round++) {
     process.stdout.write(round + " of " + num_iterations + "\r");
 
     original_code = createTopLevelCode();
-    var orig_result = [ sandbox.run_code(original_code) ];
+    var orig_result = [ sandbox.run_code(original_code), sandbox.run_code(original_code, true) ];
     errored = typeof orig_result[0] != "string";
-    if (!errored) orig_result.push(sandbox.run_code(original_code, true));
-    (errored ? fallback_options : minify_options).forEach(function(options) {
+    if (errored) {
+        println("//=============================================================");
+        println("// original code");
+        try_beautify(original_code, false, orig_result[0], println);
+        println();
+        println();
+        println("original result:");
+        println(orig_result[0]);
+        println();
+    }
+    minify_options.forEach(function(options) {
         var o = JSON.parse(options);
         var toplevel = sandbox.has_toplevel(o);
+        o.validate = true;
         uglify_code = UglifyJS.minify(original_code, o);
         original_result = orig_result[toplevel ? 1 : 0];
         if (!uglify_code.error) {
             uglify_code = uglify_code.code;
             uglify_result = sandbox.run_code(uglify_code, toplevel);
             ok = sandbox.same_stdout(original_result, uglify_result);
-            if (!ok && typeof uglify_result == "string" && o.compress && o.compress.unsafe_math) {
+            // ignore declaration order of global variables
+            if (!ok && !toplevel) {
+                ok = sandbox.same_stdout(sandbox.run_code(sort_globals(original_code)), sandbox.run_code(sort_globals(uglify_code)));
+            }
+            // ignore numerical imprecision caused by `unsafe_math`
+            if (!ok && o.compress && o.compress.unsafe_math && typeof original_result == "string" && typeof uglify_result == "string") {
                 ok = fuzzy_match(original_result, uglify_result);
                 if (!ok) {
                     var fuzzy_result = sandbox.run_code(original_code.replace(/( - 0\.1){3}/g, " - 0.3"), toplevel);
                     ok = sandbox.same_stdout(fuzzy_result, uglify_result);
                 }
             }
+            // ignore difference in error message caused by Temporal Dead Zone
+            if (!ok && errored) ok = uglify_result.name == "ReferenceError" && original_result.name == "ReferenceError";
+            // ignore difference in error message caused by `in`
+            // ignore difference in depth of termination caused by infinite recursion
+            if (!ok) {
+                var orig_skipped = patch_try_catch(original_code, toplevel);
+                var uglify_skipped = patch_try_catch(uglify_code, toplevel);
+                if (orig_skipped && uglify_skipped) {
+                    ok = sandbox.same_stdout(sandbox.run_code(orig_skipped, toplevel), sandbox.run_code(uglify_skipped, toplevel));
+                }
+            }
         } else {
             uglify_code = uglify_code.error;
-            if (errored) {
-                ok = uglify_code.name == original_result.name;
-            }
+            ok = errored && uglify_code.name == original_result.name;
         }
         if (verbose || (verbose_interval && !(round % INTERVAL_COUNT)) || !ok) log(options);
-        else if (errored) {
-            println("//=============================================================");
-            println("// original code");
-            try_beautify(original_code, toplevel, original_result, println);
-            println();
-            println();
-            println("original result:");
-            println(original_result);
-            println();
-        }
         if (!ok && isFinite(num_iterations)) {
             println();
             process.exit(1);

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", [
-        "--max-old-space-size=2048",
-        "test/ufuzz"
-    ], {
-        stdio: [ "ignore", "pipe", "pipe" ]
-    }).on("exit", respawn);
-    var stdout = "";
-    child.stdout.on("data", function(data) {
-        stdout += data;
+var args = [
+    "--max-old-space-size=2048",
+    "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();
+        });
     });
-    var stderr = "";
-    child.stderr.on("data", trap).pipe(process.stdout);
-    var keepAlive = setInterval(function() {
-        var end = stdout.lastIndexOf("\r");
-        console.log(stdout.slice(stdout.lastIndexOf("\r", end - 1) + 1, end));
-        stdout = stdout.slice(end + 1);
-    }, ping);
-    var timer = setTimeout(function() {
-        clearInterval(keepAlive);
+}, 8 * 60 * 1000);
+
+function run() {
+    var child, stdout, stderr, log;
+    spawn();
+    return function() {
+        clearInterval(log);
         child.removeListener("exit", respawn);
         child.kill();
-    }, endTime - Date.now());
+    };
+
+    function spawn() {
+        child = child_process.spawn("node", args, {
+            stdio: [ "ignore", "pipe", "pipe" ]
+        }).on("exit", respawn);
+        stdout = "";
+        child.stdout.on("data", function(data) {
+            stdout += data;
+        });
+        stderr = "";
+        child.stderr.on("data", trap).pipe(process.stdout);
+        log = setInterval(function() {
+            stdout = stdout.replace(/[^\r\n]+\r(?=[^\r\n]+\r)/g, "");
+            var end = stdout.lastIndexOf("\r");
+            if (end < 0) return;
+            console.log(stdout.slice(0, end));
+            stdout = stdout.slice(end + 1);
+        }, 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/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",
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