enhance inline (#5871)

fixes #5869

.github/workflows/build.yml

@@ -9,11 +9,11 @@ jobs:
       fail-fast: false
       matrix:
         options:
-          - '-mb braces'
           - '--ie -c'
-          - '-mc'
-          - '-p acorn --toplevel -mco spidermonkey'
-          - '--toplevel -mc passes=3,pure_getters,unsafe'
+          - '-mb braces'
+          - '--toplevel -mc'
+          - '-p acorn -mco spidermonkey'
+          - '-mc passes=3,pure_getters,unsafe'
         script:
           - acorn.sh
           - bootstrap.sh
@@ -50,7 +50,7 @@ jobs:
       OPTIONS: ${{ matrix.options }}
       SCRIPT: ${{ matrix.script }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - name: Perform uglify, build & test
         shell: bash
         run: |

.github/workflows/ci.yml

@@ -7,7 +7,7 @@ jobs:
   test:
     strategy:
       matrix:
-        node: [ '0.10', '0.12', '4', '6', '8', '10', '12', '14', '16', latest ]
+        node: [ '0.10', '0.12', '4', '6', '8', '10', '12', '14', '16', '18', '20' ]
         os: [ ubuntu-latest, windows-latest ]
         script: [ compress, mocha, release/benchmark, release/jetstream ]
     name: ${{ matrix.node }} ${{ matrix.os }} ${{ matrix.script }}
@@ -15,9 +15,10 @@ jobs:
     env:
       NODE: ${{ matrix.node }}
       TYPE: ${{ matrix.script }}
+      UGLIFY_GITHUB_LAG: 10000
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/cache@v2
+      - uses: actions/checkout@v4
+      - uses: actions/cache@v4
         with:
           path: tmp
           key: tmp ${{ matrix.script }}

.github/workflows/moz.yml

@@ -0,0 +1,18 @@
+name: ESTree
+on:
+  pull_request:
+  push:
+    branches: [ master ]
+jobs:
+  test:
+    name: fuzzing
+    runs-on: ubuntu-latest
+    env:
+      NODE: latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Perform tests
+        shell: bash
+        run: |
+          . ./test/release/install.sh
+          node test/mozilla-ast.js 5000

.github/workflows/ufuzz.yml

@@ -32,7 +32,7 @@ jobs:
     env:
       NODE: ${{ matrix.node }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - name: Perform fuzzing
         shell: bash
         run: |

CONTRIBUTING.md

@@ -3,7 +3,7 @@ Contributing
 
 ## Documentation
 
-Every new feature and API change should be accompanied by a README additon.
+Every new feature and API change should be accompanied by a README addition.
 
 ## Testing
 

LICENSE

@@ -1,6 +1,6 @@
 UglifyJS is released under the BSD license:
 
-Copyright 2012-2019 (c) Mihai Bazon <mihai.bazon@gmail.com>
+Copyright 2012-2024 (c) Mihai Bazon <mihai.bazon@gmail.com>
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions

README.md

@@ -54,8 +54,6 @@ a double dash to prevent input files being used as option arguments:
                                                 modules and Userscripts that may
                                                 be anonymous function wrapped (IIFE)
                                                 by the .user.js engine `caller`.
-                                `expression`  Parse a single expression, rather than
-                                              a program (for parsing JSON).
                                 `spidermonkey`  Assume input files are SpiderMonkey
                                                 AST format (as JSON).
     -c, --compress [options]    Enable compressor/specify compressor options:
@@ -111,6 +109,8 @@ a double dash to prevent input files being used as option arguments:
     -d, --define <expr>[=value] Global definitions.
     -e, --enclose [arg[:value]] Embed everything in a big function, with configurable
                                 argument(s) & value(s).
+    --expression                Parse a single expression, rather than a program
+                                (for parsing JSON).
     --ie                        Support non-standard Internet Explorer.
                                 Equivalent to setting `ie: true` in `minify()`
                                 for `compress`, `mangle` and `output` options.
@@ -119,6 +119,8 @@ a double dash to prevent input files being used as option arguments:
     --keep-fnames               Do not mangle/drop function names.  Useful for
                                 code relying on Function.prototype.name.
     --module                    Process input as ES module (implies --toplevel)
+    --no-module                 Avoid optimizations which may alter runtime behavior
+                                under prior versions of JavaScript.
     --name-cache <file>         File to hold mangled name mappings.
     --self                      Build UglifyJS as a library (implies --wrap UglifyJS)
     --source-map [options]      Enable source map/specify source map options:
@@ -327,7 +329,7 @@ unquoted style (`o.foo`). Example:
 // stuff.js
 var o = {
     "foo": 1,
-    bar: 3
+    bar: 3,
 };
 o.foo += o.bar;
 console.log(o.foo);
@@ -339,6 +341,16 @@ $ uglifyjs stuff.js --mangle-props keep_quoted -c -m
 var o={foo:1,o:3};o.foo+=o.o,console.log(o.foo);
 ```
 
+If the minified output will be processed again by UglifyJS, consider specifying
+`keep_quoted_props` so the same property names are preserved:
+
+```bash
+$ uglifyjs stuff.js --mangle-props keep_quoted -c -m -O keep_quoted_props
+```
+```javascript
+var o={"foo":1,o:3};o.foo+=o.o,console.log(o.foo);
+```
+
 ### Debugging property name mangling
 
 You can also pass `--mangle-props debug` in order to mangle property names
@@ -504,6 +516,8 @@ if (result.error) throw result.error;
 - `compress` (default: `{}`) — pass `false` to skip compressing entirely.
   Pass an object to specify custom [compress options](#compress-options).
 
+- `expression` (default: `false`) — parse as a single expression, e.g. JSON.
+
 - `ie` (default: `false`) — enable workarounds for Internet Explorer bugs.
 
 - `keep_fargs` (default: `false`) — pass `true` to prevent discarding or mangling
@@ -518,9 +532,9 @@ if (result.error) throw result.error;
   - `mangle.properties` (default: `false`) — a subcategory of the mangle option.
     Pass an object to specify custom [mangle property options](#mangle-properties-options).
 
-- `module` (default: `false`) — set to `true` if you wish to process input as
-  ES module, i.e. implicit `"use strict";` and support for top-level `await`,
-  alongside with `toplevel` enabled.
+- `module` (default: `true`) — process input as ES module, i.e. implicit
+  `"use strict";` and support for top-level `await`. When explicitly specified,
+  also enables `toplevel`.
 
 - `nameCache` (default: `null`) — pass an empty object `{}` or a previously
   used `nameCache` object if you wish to cache mangled variable and
@@ -633,10 +647,8 @@ to be `false` and all symbol names will be omitted.
 
 - `bare_returns` (default: `false`) — support top level `return` statements
 
-- `expression` (default: `false`) — parse as a single expression, e.g. JSON
-
 - `html5_comments` (default: `true`) — process HTML comment as workaround for
-  browsers which do not recognise `<script>` tags
+  browsers which do not recognize `<script>` tags
 
 - `module` (default: `false`) — set to `true` if you wish to process input as
   ES module, i.e. implicit `"use strict";` and support for top-level `await`.
@@ -740,10 +752,10 @@ to be `false` and all symbol names will be omitted.
 - `merge_vars` (default: `true`) — combine and reuse variables.
 
 - `module` (default: `false`) — set to `true` if you wish to process input as
-  ES module, i.e. implicit `"use strict";` alongside with `toplevel` enabled.
+  ES module, i.e. implicit `"use strict";`.
 
 - `negate_iife` (default: `true`) — negate "Immediately-Called Function Expressions"
-  where the return value is discarded, to avoid the parens that the
+  where the return value is discarded, to avoid the parentheses that the
   code generator would insert.
 
 - `objects` (default: `true`) — compact duplicate keys in object literals.
@@ -767,11 +779,11 @@ to be `false` and all symbol names will be omitted.
   overhead (compression will be slower). Make sure symbols under `pure_funcs`
   are also under `mangle.reserved` to avoid mangling.
 
-- `pure_getters` (default: `"strict"`) — If you pass `true` for
-  this, UglifyJS will assume that object property access
-  (e.g. `foo.bar` or `foo["bar"]`) doesn't have any side effects.
-  Specify `"strict"` to treat `foo.bar` as side-effect-free only when
-  `foo` is certain to not throw, i.e. not `null` or `undefined`.
+- `pure_getters` (default: `"strict"`) — Pass `true` for UglifyJS to assume that
+  object property access (e.g. `foo.bar` or `a[42]`) does not throw exception or
+  alter program states via getter function. Pass `"strict"` to allow dropping or
+  reordering `foo.bar` only if `foo` is not `null` or `undefined` and is safe to
+  access as a variable. Pass `false` to retain all property accesses.
 
 - `reduce_funcs` (default: `true`) — Allows single-use functions to be
   inlined as function expressions when permissible allowing further
@@ -841,7 +853,7 @@ 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`
+- `varify` (default: `true`) — convert block-scoped declarations into `var`
   whenever safe to do so
 
 - `yields` (default: `true`) — apply optimizations to `yield` expressions
@@ -881,12 +893,15 @@ UglifyJS.minify(code, { mangle: { toplevel: true } }).code;
 
 ### Mangle properties options
 
-- `builtins` (default: `false`) — Use `true` to allow the mangling of builtin
-  DOM properties. Not recommended to override this setting.
+- `builtins` (default: `false`) — Use `true` to allow the mangling of built-in
+  properties of JavaScript API. Not recommended to override this setting.
 
 - `debug` (default: `false`) — Mangle names with the original name still present.
   Pass an empty string `""` to enable, or a non-empty string to set the debug suffix.
 
+- `domprops` (default: `false`) — Use `true` to allow the mangling of properties
+  commonly found in Document Object Model. Not recommended to override this setting.
+
 - `keep_fargs` (default: `false`) — Use `true` to prevent mangling of function
   arguments.
 
@@ -912,9 +927,8 @@ can pass additional arguments that control the code output:
   regexps (affects directives with non-ascii characters becoming invalid)
 
 - `beautify` (default: `true`) — whether to actually beautify the output.
-  Passing `-b` will set this to true, but you might need to pass `-b` even
-  when you want to generate minified code, in order to specify additional
-  arguments, so you can use `-b beautify=false` to override it.
+  Passing `-b` will set this to true. Use `-O` if you want to generate minified
+  code and specify additional arguments.
 
 - `braces` (default: `false`) — always insert braces in `if`, `for`,
   `do`, `while` or `with` statements, even if their body is a single
@@ -930,6 +944,9 @@ can pass additional arguments that control the code output:
   }
   ```
 
+- `extendscript` (default: `false`) — enable workarounds for Adobe ExtendScript
+  bugs
+
 - `galio` (default: `false`) — enable workarounds for ANT Galio bugs
 
 - `indent_level` (default: `4`) — indent by specified number of spaces or the
@@ -1359,7 +1376,7 @@ To allow for better optimizations, the compiler makes various assumptions:
   // SyntaxError: The left-hand side of a for-of loop may not be 'async'.
   ```
   UglifyJS may modify the input which in turn may suppress those errors.
-- Later versions of Chrome and Node.js will give incorrect results with the
+- Some versions of Chrome and Node.js will give incorrect results with the
   following:
   ```javascript
   console.log({
@@ -1368,9 +1385,15 @@ To allow for better optimizations, the compiler makes various assumptions:
           return "FAIL";
       },
       [42]: "PASS",
+  }[42], {
+      ...console,
+      get 42() {
+          return "FAIL";
+      },
+      42: "PASS",
   }[42]);
-  // Expected: "PASS"
-  // Actual:   "FAIL"
+  // Expected: "PASS PASS"
+  // Actual:   "PASS FAIL"
   ```
   UglifyJS may modify the input which in turn may suppress those errors.
 - Earlier versions of JavaScript will throw `TypeError` with the following:
@@ -1440,3 +1463,17 @@ To allow for better optimizations, the compiler makes various assumptions:
   // Actual:   TypeError: invalid assignment to const 'f'
   ```
   UglifyJS may modify the input which in turn may suppress those errors.
+- Adobe ExtendScript will give incorrect results with the following:
+  ```javascript
+  alert(true ? "PASS" : false ? "FAIL" : null);
+  // Expected: "PASS"
+  // Actual:   "FAIL"
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.
+- Adobe ExtendScript will give incorrect results with the following:
+  ```javascript
+  alert(42 ? null ? "FAIL" : "PASS" : "FAIL");
+  // Expected: "PASS"
+  // Actual:   SyntaxError: Expected: :
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.

bin/uglifyjs

@@ -104,10 +104,12 @@ function process_option(name, no_value) {
                 "  --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).",
+                "  --expression                             Parse a single expression, rather than a program.",
                 "  --ie                                     Support non-standard Internet Explorer.",
                 "  --keep-fargs                             Do not mangle/drop function arguments.",
                 "  --keep-fnames                            Do not mangle/drop function names. Useful for code relying on Function.prototype.name.",
-                "  --module                                 Process input as ES module (implies --toplevel)",
+                "  --module                                 Process input as ES module (implies --toplevel).",
+                "  --no-module                              Process input with improved JavaScript compatibility.",
                 "  --name-cache <file>                      File to hold mangled name mappings.",
                 "  --rename                                 Force symbol expansion.",
                 "  --no-rename                              Disable symbol expansion.",
@@ -151,9 +153,9 @@ function process_option(name, no_value) {
         options[name] = read_value();
         break;
       case "annotations":
+      case "expression":
       case "ie":
       case "ie8":
-      case "module":
       case "timings":
       case "toplevel":
       case "v8":
@@ -199,6 +201,12 @@ function process_option(name, no_value) {
         if (typeof options.mangle != "object") options.mangle = {};
         options.mangle.properties = parse_js(read_value(), options.mangle.properties);
         break;
+      case "module":
+        options.module = true;
+        break;
+      case "no-module":
+        options.module = false;
+        break;
       case "name-cache":
         nameCache = read_value(true);
         options.nameCache = JSON.parse(read_file(nameCache, "{}"));
@@ -236,17 +244,6 @@ if (specified["beautify"] && specified["output-opts"]) fatal("--beautify cannot
 [ "compress", "mangle" ].forEach(function(name) {
     if (!(name in options)) options[name] = false;
 });
-if (options.mangle && options.mangle.properties) {
-    if (options.mangle.properties.domprops) {
-        delete options.mangle.properties.domprops;
-    } else {
-        if (typeof options.mangle.properties != "object") options.mangle.properties = {};
-        if (!Array.isArray(options.mangle.properties.reserved)) options.mangle.properties.reserved = [];
-        require("../tools/domprops").forEach(function(name) {
-            UglifyJS.push_uniq(options.mangle.properties.reserved, name);
-        });
-    }
-}
 if (/^ast|spidermonkey$/.test(output)) {
     if (typeof options.output != "object") options.output = {};
     options.output.ast = true;
@@ -276,6 +273,8 @@ if (specified["self"]) {
     if (paths.length) UglifyJS.AST_Node.warn("Ignoring input files since --self was passed");
     if (!options.wrap) options.wrap = "UglifyJS";
     paths = UglifyJS.FILES;
+} else if (paths.length) {
+    paths = simple_glob(paths);
 }
 if (specified["in-situ"]) {
     if (output && output != "spidermonkey" || specified["reduce-test"] || specified["self"]) {
@@ -290,7 +289,7 @@ if (specified["in-situ"]) {
         run();
     });
 } else if (paths.length) {
-    simple_glob(paths).forEach(function(name) {
+    paths.forEach(function(name) {
         files[convert_path(name)] = read_file(name);
     });
     run();
@@ -302,9 +301,19 @@ if (specified["in-situ"]) {
     process.stdin.setEncoding("utf8");
     process.stdin.once("data", function() {
         clearTimeout(timerId);
-    }).on("data", function(chunk) {
+    }).on("data", process.stdin.isTTY ? function(chunk) {
+        // emulate console input termination via Ctrl+D / Ctrl+Z
+        var match = /[\x04\x1a]\r?\n?$/.exec(chunk);
+        if (match) {
+            chunks.push(chunk.slice(0, -match[0].length));
+            process.stdin.pause();
+            process.stdin.emit("end");
+        } else {
+            chunks.push(chunk);
+        }
+    } : function(chunk) {
         chunks.push(chunk);
-    }).on("end", function() {
+    }).once("end", function() {
         files = { STDIN: chunks.join("") };
         run();
     });
@@ -489,33 +498,42 @@ function fatal(message) {
 
 // A file glob function that only supports "*" and "?" wildcards in the basename.
 // Example: "foo/bar/*baz??.*.js"
-// Argument `glob` may be a string or an array of strings.
+// Argument `paths` must be an array of strings.
 // Returns an array of strings. Garbage in, garbage out.
-function simple_glob(glob) {
-    if (Array.isArray(glob)) {
-        return [].concat.apply([], glob.map(simple_glob));
-    }
-    if (glob.match(/\*|\?/)) {
-        var dir = path.dirname(glob);
-        try {
-            var entries = fs.readdirSync(dir);
-        } catch (ex) {}
-        if (entries) {
-            var pattern = "^" + path.basename(glob)
-                .replace(/[.+^$[\]\\(){}]/g, "\\$&")
-                .replace(/\*/g, "[^/\\\\]*")
-                .replace(/\?/g, "[^/\\\\]") + "$";
-            var mod = process.platform === "win32" ? "i" : "";
-            var rx = new RegExp(pattern, mod);
-            var results = entries.sort().filter(function(name) {
-                return rx.test(name);
-            }).map(function(name) {
-                return path.join(dir, name);
-            });
-            if (results.length) return results;
+function simple_glob(paths) {
+    return paths.reduce(function(paths, glob) {
+        if (/\*|\?/.test(glob)) {
+            var dir = path.dirname(glob);
+            try {
+                var entries = fs.readdirSync(dir).filter(function(name) {
+                    try {
+                        return fs.statSync(path.join(dir, name)).isFile();
+                    } catch (ex) {
+                        return false;
+                    }
+                });
+            } catch (ex) {}
+            if (entries) {
+                var pattern = "^" + path.basename(glob)
+                    .replace(/[.+^$[\]\\(){}]/g, "\\$&")
+                    .replace(/\*/g, "[^/\\\\]*")
+                    .replace(/\?/g, "[^/\\\\]") + "$";
+                var mod = process.platform === "win32" ? "i" : "";
+                var rx = new RegExp(pattern, mod);
+                var results = entries.filter(function(name) {
+                    return rx.test(name);
+                }).sort().map(function(name) {
+                    return path.join(dir, name);
+                });
+                if (results.length) {
+                    [].push.apply(paths, results);
+                    return paths;
+                }
+            }
         }
-    }
-    return [ glob ];
+        paths.push(glob);
+        return paths;
+    }, []);
 }
 
 function read_file(path, default_value) {

lib/ast.js

@@ -109,6 +109,9 @@ var AST_Node = DEFNODE("Node", "start end", {
         start: "[AST_Token] The first token of this node",
         end: "[AST_Token] The last token of this node"
     },
+    equals: function(node) {
+        return this.TYPE == node.TYPE && this._equals(node);
+    },
     walk: function(visitor) {
         visitor.visit(this);
     },
@@ -125,12 +128,7 @@ var AST_Node = DEFNODE("Node", "start end", {
         var marker = {};
         this.walk(new TreeWalker(function(node) {
             if (node.validate_visited === marker) {
-                throw new Error(string_template("cannot reuse {type} from [{file}:{line},{col}]", {
-                    type: "AST_" + node.TYPE,
-                    file: node.start.file,
-                    line: node.start.line,
-                    col: node.start.col,
-                }));
+                throw new Error(string_template("cannot reuse AST_{TYPE} from [{start}]", node));
             }
             node.validate_visited = marker;
         }));
@@ -138,6 +136,7 @@ var AST_Node = DEFNODE("Node", "start end", {
 }, null);
 
 DEF_BITPROPS(AST_Node, [
+    // AST_Node
     "_optimized",
     "_squeezed",
     // AST_Call
@@ -170,8 +169,8 @@ DEF_BITPROPS(AST_Node, [
     "private",
     // AST_Call
     "pure",
-    // AST_Assign
-    "redundant",
+    // AST_Node
+    "single_use",
     // AST_ClassProperty
     "static",
     // AST_Call
@@ -231,6 +230,24 @@ AST_Node.disable_validation = function() {
     while (restore = restore_transforms.pop()) restore();
 };
 
+function all_equals(k, l) {
+    return k.length == l.length && all(k, function(m, i) {
+        return m.equals(l[i]);
+    });
+}
+
+function list_equals(s, t) {
+    return s.length == t.length && all(s, function(u, i) {
+        return u == t[i];
+    });
+}
+
+function prop_equals(u, v) {
+    if (u === v) return true;
+    if (u == null) return v == null;
+    return u instanceof AST_Node && v instanceof AST_Node && u.equals(v);
+}
+
 /* -----[ statements ]----- */
 
 var AST_Statement = DEFNODE("Statement", null, {
@@ -242,6 +259,7 @@ var AST_Statement = DEFNODE("Statement", null, {
 
 var AST_Debugger = DEFNODE("Debugger", null, {
     $documentation: "Represents a debugger statement",
+    _equals: return_true,
 }, AST_Statement);
 
 var AST_Directive = DEFNODE("Directive", "quote value", {
@@ -250,6 +268,9 @@ var AST_Directive = DEFNODE("Directive", "quote value", {
         quote: "[string?] the original quote character",
         value: "[string] The value of this directive as a plain string (it's not an AST_String!)",
     },
+    _equals: function(node) {
+        return this.value == node.value;
+    },
     _validate: function() {
         if (this.quote != null) {
             if (typeof this.quote != "string") throw new Error("quote must be string");
@@ -260,7 +281,8 @@ var AST_Directive = DEFNODE("Directive", "quote value", {
 }, AST_Statement);
 
 var AST_EmptyStatement = DEFNODE("EmptyStatement", null, {
-    $documentation: "The empty statement (empty block or simply a semicolon)"
+    $documentation: "The empty statement (empty block or simply a semicolon)",
+    _equals: return_true,
 }, AST_Statement);
 
 function is_statement(node) {
@@ -291,6 +313,9 @@ var AST_SimpleStatement = DEFNODE("SimpleStatement", "body", {
     $propdoc: {
         body: "[AST_Node] an expression node (should not be instanceof AST_Statement)",
     },
+    _equals: function(node) {
+        return this.body.equals(node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -305,7 +330,7 @@ var AST_SimpleStatement = DEFNODE("SimpleStatement", "body", {
 var AST_BlockScope = DEFNODE("BlockScope", "_var_names enclosed functions make_def parent_scope variables", {
     $documentation: "Base class for all statements introducing a lexical scope",
     $propdoc: {
-        enclosed: "[SymbolDef*/S] a list of all symbol definitions that are accessed from this scope or any subscopes",
+        enclosed: "[SymbolDef*/S] a list of all symbol definitions that are accessed from this scope or any inner scopes",
         functions: "[Dictionary/S] like `variables`, but only lists function declarations",
         parent_scope: "[AST_Scope?/S] link to the parent scope",
         variables: "[Dictionary/S] a map of name ---> SymbolDef for all variables/functions defined in this scope",
@@ -342,6 +367,9 @@ var AST_Block = DEFNODE("Block", "body", {
     $propdoc: {
         body: "[AST_Statement*] an array of statements"
     },
+    _equals: function(node) {
+        return all_equals(this.body, node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -376,6 +404,10 @@ var AST_LabeledStatement = DEFNODE("LabeledStatement", "label", {
     $propdoc: {
         label: "[AST_Label] a label definition"
     },
+    _equals: function(node) {
+        return this.label.equals(node.label)
+            && this.body.equals(node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -417,6 +449,10 @@ var AST_DWLoop = DEFNODE("DWLoop", "condition", {
     $propdoc: {
         condition: "[AST_Node] the loop condition.  Should not be instanceof AST_Statement"
     },
+    _equals: function(node) {
+        return this.body.equals(node.body)
+            && this.condition.equals(node.condition);
+    },
     _validate: function() {
         if (this.TYPE == "DWLoop") throw new Error("should not instantiate AST_DWLoop");
         must_be_expression(this, "condition");
@@ -431,7 +467,7 @@ var AST_Do = DEFNODE("Do", null, {
             node.body.walk(visitor);
             node.condition.walk(visitor);
         });
-    }
+    },
 }, AST_DWLoop);
 
 var AST_While = DEFNODE("While", null, {
@@ -442,7 +478,7 @@ var AST_While = DEFNODE("While", null, {
             node.condition.walk(visitor);
             node.body.walk(visitor);
         });
-    }
+    },
 }, AST_DWLoop);
 
 var AST_For = DEFNODE("For", "init condition step", {
@@ -452,6 +488,12 @@ var AST_For = DEFNODE("For", "init condition step", {
         condition: "[AST_Node?] the `for` termination clause, or null if empty",
         step: "[AST_Node?] the `for` update clause, or null if empty"
     },
+    _equals: function(node) {
+        return prop_equals(this.init, node.init)
+            && prop_equals(this.condition, node.condition)
+            && prop_equals(this.step, node.step)
+            && this.body.equals(node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -479,6 +521,11 @@ var AST_ForEnumeration = DEFNODE("ForEnumeration", "init object", {
         init: "[AST_Node] the assignment target during iteration",
         object: "[AST_Node] the object to iterate over"
     },
+    _equals: function(node) {
+        return this.init.equals(node.init)
+            && this.object.equals(node.object)
+            && this.body.equals(node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -519,6 +566,10 @@ var AST_With = DEFNODE("With", "expression", {
     $propdoc: {
         expression: "[AST_Node] the `with` expression"
     },
+    _equals: function(node) {
+        return this.expression.equals(node.expression)
+            && this.body.equals(node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -621,6 +672,13 @@ var AST_Lambda = DEFNODE("Lambda", "argnames length_read rest safe_ids uses_argu
         });
         if (this.rest) this.rest.walk(tw);
     },
+    _equals: function(node) {
+        return prop_equals(this.rest, node.rest)
+            && prop_equals(this.name, node.name)
+            && prop_equals(this.value, node.value)
+            && all_equals(this.argnames, node.argnames)
+            && all_equals(this.body, node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -831,6 +889,11 @@ var AST_Class = DEFNODE("Class", "extends name properties", {
         extends: "[AST_Node?] the super class, or null if not specified",
         properties: "[AST_ClassProperty*] array of class properties",
     },
+    _equals: function(node) {
+        return prop_equals(this.name, node.name)
+            && prop_equals(this.extends, node.extends)
+            && all_equals(this.properties, node.properties);
+    },
     resolve: function(def_class) {
         return def_class ? this : this.parent_scope.resolve();
     },
@@ -883,6 +946,12 @@ var AST_ClassProperty = DEFNODE("ClassProperty", "key private static value", {
         static: "[boolean] whether this is a static property",
         value: "[AST_Node?] property value (AST_Accessor for getters/setters, AST_LambdaExpression for methods, null if not specified for fields)",
     },
+    _equals: function(node) {
+        return !this.private == !node.private
+            && !this.static == !node.static
+            && prop_equals(this.key, node.key)
+            && prop_equals(this.value, node.value);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -959,6 +1028,9 @@ var AST_Exit = DEFNODE("Exit", "value", {
     $propdoc: {
         value: "[AST_Node?] the value returned or thrown by this statement; could be null for AST_Return"
     },
+    _equals: function(node) {
+        return prop_equals(this.value, node.value);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -989,6 +1061,9 @@ var AST_LoopControl = DEFNODE("LoopControl", "label", {
     $propdoc: {
         label: "[AST_LabelRef?] the label, or null if none",
     },
+    _equals: function(node) {
+        return prop_equals(this.label, node.label);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1019,6 +1094,11 @@ var AST_If = DEFNODE("If", "condition alternative", {
         condition: "[AST_Node] the `if` condition",
         alternative: "[AST_Statement?] the `else` part, or null if not present"
     },
+    _equals: function(node) {
+        return this.body.equals(node.body)
+            && this.condition.equals(node.condition)
+            && prop_equals(this.alternative, node.alternative);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1042,6 +1122,10 @@ var AST_Switch = DEFNODE("Switch", "expression", {
     $propdoc: {
         expression: "[AST_Node] the `switch` “discriminant”"
     },
+    _equals: function(node) {
+        return this.expression.equals(node.expression)
+            && all_equals(this.body, node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1073,6 +1157,10 @@ var AST_Case = DEFNODE("Case", "expression", {
     $propdoc: {
         expression: "[AST_Node] the `case` expression"
     },
+    _equals: function(node) {
+        return this.expression.equals(node.expression)
+            && all_equals(this.body, node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1093,6 +1181,11 @@ var AST_Try = DEFNODE("Try", "bcatch bfinally", {
         bcatch: "[AST_Catch?] the catch block, or null if not present",
         bfinally: "[AST_Finally?] the finally block, or null if not present"
     },
+    _equals: function(node) {
+        return all_equals(this.body, node.body)
+            && prop_equals(this.bcatch, node.bcatch)
+            && prop_equals(this.bfinally, node.bfinally);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1116,6 +1209,10 @@ var AST_Catch = DEFNODE("Catch", "argname", {
     $propdoc: {
         argname: "[(AST_Destructured|AST_SymbolCatch)?] symbol for the exception, or null if not present",
     },
+    _equals: function(node) {
+        return prop_equals(this.argname, node.argname)
+            && all_equals(this.body, node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1141,6 +1238,9 @@ var AST_Definitions = DEFNODE("Definitions", "definitions", {
     $propdoc: {
         definitions: "[AST_VarDef*] array of variable definitions"
     },
+    _equals: function(node) {
+        return all_equals(this.definitions, node.definitions);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1197,6 +1297,10 @@ var AST_VarDef = DEFNODE("VarDef", "name value", {
         name: "[AST_Destructured|AST_SymbolVar] name of the variable",
         value: "[AST_Node?] initializer, or null of there's no initializer",
     },
+    _equals: function(node) {
+        return this.name.equals(node.name)
+            && prop_equals(this.value, node.value);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1216,6 +1320,9 @@ var AST_ExportDeclaration = DEFNODE("ExportDeclaration", "body", {
     $propdoc: {
         body: "[AST_DefClass|AST_Definitions|AST_LambdaDefinition] the statement to export",
     },
+    _equals: function(node) {
+        return this.body.equals(node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1236,6 +1343,9 @@ var AST_ExportDefault = DEFNODE("ExportDefault", "body", {
     $propdoc: {
         body: "[AST_Node] the default export",
     },
+    _equals: function(node) {
+        return this.body.equals(node.body);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1249,29 +1359,29 @@ var AST_ExportDefault = DEFNODE("ExportDefault", "body", {
     },
 }, AST_Statement);
 
-var AST_ExportForeign = DEFNODE("ExportForeign", "aliases keys path quote", {
+var AST_ExportForeign = DEFNODE("ExportForeign", "aliases keys path", {
     $documentation: "An `export ... from '...'` statement",
     $propdoc: {
-        aliases: "[string*] array of aliases to export",
-        keys: "[string*] array of keys to import",
-        path: "[string] the path to import module",
-        quote: "[string?] the original quote character",
+        aliases: "[AST_String*] array of aliases to export",
+        keys: "[AST_String*] array of keys to import",
+        path: "[AST_String] the path to import module",
+    },
+    _equals: function(node) {
+        return this.path.equals(node.path)
+            && all_equals(this.aliases, node.aliases)
+            && all_equals(this.keys, node.keys);
     },
     _validate: function() {
         if (this.aliases.length != this.keys.length) {
             throw new Error("aliases:key length mismatch: " + this.aliases.length + " != " + this.keys.length);
         }
         this.aliases.forEach(function(name) {
-            if (typeof name != "string") throw new Error("aliases must contain string");
+            if (!(name instanceof AST_String)) throw new Error("aliases must contain AST_String");
         });
         this.keys.forEach(function(name) {
-            if (typeof name != "string") throw new Error("keys must contain string");
+            if (!(name instanceof AST_String)) throw new Error("keys must contain AST_String");
         });
-        if (typeof this.path != "string") throw new Error("path must be string");
-        if (this.quote != null) {
-            if (typeof this.quote != "string") throw new Error("quote must be string");
-            if (!/^["']$/.test(this.quote)) throw new Error("invalid quote: " + this.quote);
-        }
+        if (!(this.path instanceof AST_String)) throw new Error("path must be AST_String");
     },
 }, AST_Statement);
 
@@ -1280,6 +1390,9 @@ var AST_ExportReferences = DEFNODE("ExportReferences", "properties", {
     $propdoc: {
         properties: "[AST_SymbolExport*] array of aliases to export",
     },
+    _equals: function(node) {
+        return all_equals(this.properties, node.properties);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1295,14 +1408,20 @@ var AST_ExportReferences = DEFNODE("ExportReferences", "properties", {
     },
 }, AST_Statement);
 
-var AST_Import = DEFNODE("Import", "all default path properties quote", {
+var AST_Import = DEFNODE("Import", "all default path properties", {
     $documentation: "An `import` statement",
     $propdoc: {
         all: "[AST_SymbolImport?] the imported namespace, or null if not specified",
         default: "[AST_SymbolImport?] the alias for default `export`, or null if not specified",
-        path: "[string] the path to import module",
+        path: "[AST_String] the path to import module",
         properties: "[(AST_SymbolImport*)?] array of aliases, or null if not specified",
-        quote: "[string?] the original quote character",
+    },
+    _equals: function(node) {
+        return this.path.equals(node.path)
+            && prop_equals(this.all, node.all)
+            && prop_equals(this.default, node.default)
+            && !this.properties == !node.properties
+            && (!this.properties || all_equals(this.properties, node.properties));
     },
     walk: function(visitor) {
         var node = this;
@@ -1321,16 +1440,12 @@ var AST_Import = DEFNODE("Import", "all default path properties quote", {
         }
         if (this.default != null) {
             if (!(this.default instanceof AST_SymbolImport)) throw new Error("default must be AST_SymbolImport");
-            if (this.default.key !== "") throw new Error("invalid default key: " + this.default.key);
+            if (this.default.key.value !== "") throw new Error("invalid default key: " + this.default.key.value);
         }
-        if (typeof this.path != "string") throw new Error("path must be string");
+        if (!(this.path instanceof AST_String)) throw new Error("path must be AST_String");
         if (this.properties != null) this.properties.forEach(function(node) {
             if (!(node instanceof AST_SymbolImport)) throw new Error("properties must contain AST_SymbolImport");
         });
-        if (this.quote != null) {
-            if (typeof this.quote != "string") throw new Error("quote must be string");
-            if (!/^["']$/.test(this.quote)) throw new Error("invalid quote: " + this.quote);
-        }
     },
 }, AST_Statement);
 
@@ -1340,6 +1455,10 @@ var AST_DefaultValue = DEFNODE("DefaultValue", "name value", {
         name: "[AST_Destructured|AST_SymbolDeclaration] name of the variable",
         value: "[AST_Node] value to assign if variable is `undefined`",
     },
+    _equals: function(node) {
+        return this.name.equals(node.name)
+            && this.value.equals(node.value);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1367,6 +1486,11 @@ var AST_Call = DEFNODE("Call", "args expression optional pure terminal", {
         pure: "[boolean/S] marker for side-effect-free call expression",
         terminal: "[boolean] whether the chain has ended",
     },
+    _equals: function(node) {
+        return !this.optional == !node.optional
+            && this.expression.equals(node.expression)
+            && all_equals(this.args, node.args);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1393,7 +1517,10 @@ var AST_New = DEFNODE("New", null, {
 var AST_Sequence = DEFNODE("Sequence", "expressions", {
     $documentation: "A sequence expression (comma-separated expressions)",
     $propdoc: {
-        expressions: "[AST_Node*] array of expressions (at least two)"
+        expressions: "[AST_Node*] array of expressions (at least two)",
+    },
+    _equals: function(node) {
+        return all_equals(this.expressions, node.expressions);
     },
     walk: function(visitor) {
         var node = this;
@@ -1422,6 +1549,11 @@ var AST_PropAccess = DEFNODE("PropAccess", "expression optional property termina
         property: "[AST_Node|string] the property to access.  For AST_Dot this is always a plain string, while for AST_Sub it's an arbitrary AST_Node",
         terminal: "[boolean] whether the chain has ended",
     },
+    _equals: function(node) {
+        return !this.optional == !node.optional
+            && prop_equals(this.property, node.property)
+            && this.expression.equals(node.expression);
+    },
     get_property: function() {
         var p = this.property;
         if (p instanceof AST_Constant) return p.value;
@@ -1434,8 +1566,11 @@ var AST_PropAccess = DEFNODE("PropAccess", "expression optional property termina
     },
 });
 
-var AST_Dot = DEFNODE("Dot", null, {
+var AST_Dot = DEFNODE("Dot", "quoted", {
     $documentation: "A dotted property access expression",
+    $propdoc: {
+        quoted: "[boolean] whether property is transformed from a quoted string",
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1466,6 +1601,9 @@ var AST_Spread = DEFNODE("Spread", "expression", {
     $propdoc: {
         expression: "[AST_Node] expression to be expanded",
     },
+    _equals: function(node) {
+        return this.expression.equals(node.expression);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1481,7 +1619,11 @@ var AST_Unary = DEFNODE("Unary", "operator expression", {
     $documentation: "Base class for unary expressions",
     $propdoc: {
         operator: "[string] the operator",
-        expression: "[AST_Node] expression that this unary operator applies to"
+        expression: "[AST_Node] expression that this unary operator applies to",
+    },
+    _equals: function(node) {
+        return this.operator == node.operator
+            && this.expression.equals(node.expression);
     },
     walk: function(visitor) {
         var node = this;
@@ -1511,6 +1653,11 @@ var AST_Binary = DEFNODE("Binary", "operator left right", {
         operator: "[string] the operator",
         right: "[AST_Node] right-hand side expression"
     },
+    _equals: function(node) {
+        return this.operator == node.operator
+            && this.left.equals(node.left)
+            && this.right.equals(node.right);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1532,6 +1679,11 @@ var AST_Conditional = DEFNODE("Conditional", "condition consequent alternative",
         consequent: "[AST_Node]",
         alternative: "[AST_Node]"
     },
+    _equals: function(node) {
+        return this.condition.equals(node.condition)
+            && this.consequent.equals(node.consequent)
+            && this.alternative.equals(node.alternative);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1573,6 +1725,9 @@ var AST_Await = DEFNODE("Await", "expression", {
     $propdoc: {
         expression: "[AST_Node] expression with Promise to resolve on",
     },
+    _equals: function(node) {
+        return this.expression.equals(node.expression);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1590,6 +1745,10 @@ var AST_Yield = DEFNODE("Yield", "expression nested", {
         expression: "[AST_Node?] return value for iterator, or null if undefined",
         nested: "[boolean] whether to iterate over expression as generator",
     },
+    _equals: function(node) {
+        return !this.nested == !node.nested
+            && prop_equals(this.expression, node.expression);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1612,6 +1771,9 @@ var AST_Array = DEFNODE("Array", "elements", {
     $propdoc: {
         elements: "[AST_Node*] array of elements"
     },
+    _equals: function(node) {
+        return all_equals(this.elements, node.elements);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1654,6 +1816,10 @@ var AST_DestructuredArray = DEFNODE("DestructuredArray", "elements", {
     $propdoc: {
         elements: "[(AST_DefaultValue|AST_Destructured|AST_SymbolDeclaration|AST_SymbolRef)*] array of elements",
     },
+    _equals: function(node) {
+        return prop_equals(this.rest, node.rest)
+            && all_equals(this.elements, node.elements);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1671,6 +1837,10 @@ var AST_DestructuredKeyVal = DEFNODE("DestructuredKeyVal", "key value", {
         key: "[string|AST_Node] property name.  For computed property this is an AST_Node.",
         value: "[AST_DefaultValue|AST_Destructured|AST_SymbolDeclaration|AST_SymbolRef] property value",
     },
+    _equals: function(node) {
+        return prop_equals(this.key, node.key)
+            && this.value.equals(node.value);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1692,6 +1862,10 @@ var AST_DestructuredObject = DEFNODE("DestructuredObject", "properties", {
     $propdoc: {
         properties: "[AST_DestructuredKeyVal*] array of properties",
     },
+    _equals: function(node) {
+        return prop_equals(this.rest, node.rest)
+            && all_equals(this.properties, node.properties);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1713,6 +1887,9 @@ var AST_Object = DEFNODE("Object", "properties", {
     $propdoc: {
         properties: "[(AST_ObjectProperty|AST_Spread)*] array of properties"
     },
+    _equals: function(node) {
+        return all_equals(this.properties, node.properties);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1736,6 +1913,10 @@ var AST_ObjectProperty = DEFNODE("ObjectProperty", "key value", {
         key: "[string|AST_Node] property name.  For computed property this is an AST_Node.",
         value: "[AST_Node] property value.  For getters and setters this is an AST_Accessor.",
     },
+    _equals: function(node) {
+        return prop_equals(this.key, node.key)
+            && this.value.equals(node.value);
+    },
     walk: function(visitor) {
         var node = this;
         visitor.visit(node, function() {
@@ -1790,6 +1971,9 @@ var AST_Symbol = DEFNODE("Symbol", "scope name thedef", {
         scope: "[AST_Scope/S] the current scope (not necessarily the definition scope)",
         thedef: "[SymbolDef/S] the definition of this symbol"
     },
+    _equals: function(node) {
+        return this.thedef ? this.thedef === node.thedef : this.name == node.name;
+    },
     _validate: function() {
         if (this.TYPE == "Symbol") throw new Error("should not instantiate AST_Symbol");
         if (typeof this.name != "string") throw new Error("name must be string");
@@ -1807,10 +1991,14 @@ var AST_SymbolConst = DEFNODE("SymbolConst", null, {
 var AST_SymbolImport = DEFNODE("SymbolImport", "key", {
     $documentation: "Symbol defined by an `import` statement",
     $propdoc: {
-        key: "[string] the original `export` name",
+        key: "[AST_String] the original `export` name",
+    },
+    _equals: function(node) {
+        return this.name == node.name
+            && this.key.equals(node.key);
     },
     _validate: function() {
-        if (typeof this.key != "string") throw new Error("key must be string");
+        if (!(this.key instanceof AST_String)) throw new Error("key must be AST_String");
     },
 }, AST_SymbolConst);
 
@@ -1864,10 +2052,14 @@ var AST_SymbolRef = DEFNODE("SymbolRef", "fixed in_arg redef", {
 var AST_SymbolExport = DEFNODE("SymbolExport", "alias", {
     $documentation: "Reference in an `export` statement",
     $propdoc: {
-        alias: "[string] the `export` alias",
+        alias: "[AST_String] the `export` alias",
+    },
+    _equals: function(node) {
+        return this.name == node.name
+            && this.alias.equals(node.alias);
     },
     _validate: function() {
-        if (typeof this.alias != "string") throw new Error("alias must be string");
+        if (!(this.alias instanceof AST_String)) throw new Error("alias must be AST_String");
     },
 }, AST_SymbolRef);
 
@@ -1877,6 +2069,7 @@ var AST_LabelRef = DEFNODE("LabelRef", null, {
 
 var AST_ObjectIdentity = DEFNODE("ObjectIdentity", null, {
     $documentation: "Base class for `super` & `this`",
+    _equals: return_true,
     _validate: function() {
         if (this.TYPE == "ObjectIdentity") throw new Error("should not instantiate AST_ObjectIdentity");
     },
@@ -1911,7 +2104,12 @@ var AST_Template = DEFNODE("Template", "expressions strings tag", {
     $propdoc: {
         expressions: "[AST_Node*] the placeholder expressions",
         strings: "[string*] the raw text segments",
-        tag: "[AST_Node] tag function, or null if absent",
+        tag: "[AST_Node?] tag function, or null if absent",
+    },
+    _equals: function(node) {
+        return prop_equals(this.tag, node.tag)
+            && list_equals(this.strings, node.strings)
+            && all_equals(this.expressions, node.expressions);
     },
     walk: function(visitor) {
         var node = this;
@@ -1936,6 +2134,9 @@ var AST_Template = DEFNODE("Template", "expressions strings tag", {
 
 var AST_Constant = DEFNODE("Constant", null, {
     $documentation: "Base class for all constants",
+    _equals: function(node) {
+        return this.value === node.value;
+    },
     _validate: function() {
         if (this.TYPE == "Constant") throw new Error("should not instantiate AST_Constant");
     },
@@ -1984,6 +2185,9 @@ var AST_RegExp = DEFNODE("RegExp", "value", {
     $propdoc: {
         value: "[RegExp] the actual regexp"
     },
+    _equals: function(node) {
+        return "" + this.value == "" + node.value;
+    },
     _validate: function() {
         if (!(this.value instanceof RegExp)) throw new Error("value must be RegExp");
     },
@@ -1991,6 +2195,7 @@ var AST_RegExp = DEFNODE("RegExp", "value", {
 
 var AST_Atom = DEFNODE("Atom", null, {
     $documentation: "Base class for atoms",
+    _equals: return_true,
     _validate: function() {
         if (this.TYPE == "Atom") throw new Error("should not instantiate AST_Atom");
     },

lib/minify.js

@@ -76,19 +76,20 @@ function minify(files, options) {
             annotations: undefined,
             compress: {},
             enclose: false,
+            expression: false,
             ie: false,
             ie8: false,
             keep_fargs: false,
             keep_fnames: false,
             mangle: {},
-            module: false,
+            module: undefined,
             nameCache: null,
             output: {},
             parse: {},
             rename: undefined,
             sourceMap: false,
             timings: false,
-            toplevel: !!(options && options["module"]),
+            toplevel: options && !options["expression"] && options["module"] ? true : undefined,
             v8: false,
             validate: false,
             warnings: false,
@@ -98,12 +99,14 @@ function minify(files, options) {
         if (options.validate) AST_Node.enable_validation();
         var timings = options.timings && { start: Date.now() };
         if (options.annotations !== undefined) set_shorthand("annotations", options, [ "compress", "output" ]);
+        if (options.expression) set_shorthand("expression", options, [ "compress", "parse" ]);
         if (options.ie8) options.ie = options.ie || options.ie8;
         if (options.ie) set_shorthand("ie", options, [ "compress", "mangle", "output", "rename" ]);
         if (options.keep_fargs) set_shorthand("keep_fargs", options, [ "compress", "mangle", "rename" ]);
         if (options.keep_fnames) set_shorthand("keep_fnames", options, [ "compress", "mangle", "rename" ]);
+        if (options.module === undefined && !options.ie) options.module = true;
         if (options.module) set_shorthand("module", options, [ "compress", "parse" ]);
-        if (options.toplevel) set_shorthand("toplevel", options, [ "compress", "mangle", "rename" ]);
+        if (options.toplevel !== undefined) set_shorthand("toplevel", options, [ "compress", "mangle", "rename" ]);
         if (options.v8) set_shorthand("v8", options, [ "mangle", "output", "rename" ]);
         if (options.webkit) set_shorthand("webkit", options, [ "compress", "mangle", "output", "rename" ]);
         var quoted_props;
@@ -153,13 +156,11 @@ function minify(files, options) {
         }, options.warnings == "verbose");
         if (timings) timings.parse = Date.now();
         var toplevel;
-        if (files instanceof AST_Toplevel) {
+        options.parse = options.parse || {};
+        if (files instanceof AST_Node) {
             toplevel = files;
         } else {
-            if (typeof files == "string") {
-                files = [ files ];
-            }
-            options.parse = options.parse || {};
+            if (typeof files == "string") files = [ files ];
             options.parse.toplevel = null;
             var source_map_content = options.sourceMap && options.sourceMap.content;
             if (typeof source_map_content == "string" && source_map_content != "inline") {
@@ -171,17 +172,14 @@ function minify(files, options) {
                 options.parse.toplevel = toplevel = parse(files[name], options.parse);
                 if (source_map_content == "inline") {
                     var inlined_content = read_source_map(name, toplevel);
-                    if (inlined_content) {
-                        options.sourceMap.orig[name] = parse_source_map(inlined_content);
-                    }
+                    if (inlined_content) options.sourceMap.orig[name] = parse_source_map(inlined_content);
                 } else if (source_map_content) {
                     options.sourceMap.orig[name] = source_map_content;
                 }
             }
         }
-        if (quoted_props) {
-            reserve_quoted_keys(toplevel, quoted_props);
-        }
+        if (options.parse.expression) toplevel = toplevel.wrap_expression();
+        if (quoted_props) reserve_quoted_keys(toplevel, quoted_props);
         [ "enclose", "wrap" ].forEach(function(action) {
             var option = options[action];
             if (!option) return;
@@ -208,7 +206,9 @@ function minify(files, options) {
             toplevel.mangle_names(options.mangle);
         }
         if (timings) timings.properties = Date.now();
+        if (quoted_props) reserve_quoted_keys(toplevel, quoted_props);
         if (options.mangle && options.mangle.properties) mangle_properties(toplevel, options.mangle.properties);
+        if (options.parse.expression) toplevel = toplevel.unwrap_expression();
         if (timings) timings.output = Date.now();
         var result = {};
         var output = defaults(options.output, {

lib/mozilla-ast.js

@@ -125,6 +125,16 @@
                 body: normalize_directives(from_moz(M.body).body),
             });
         },
+        CallExpression: function(M) {
+            return new AST_Call({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                expression: from_moz(M.callee),
+                args: M.arguments.map(from_moz),
+                optional: M.optional,
+                pure: M.pure,
+            });
+        },
         ClassDeclaration: function(M) {
             return new AST_DefClass({
                 start: my_start_token(M),
@@ -192,6 +202,19 @@
                 value: from_moz(M.value),
             });
         },
+        StaticBlock: function(M) {
+            var start = my_start_token(M);
+            var end = my_end_token(M);
+            return new AST_ClassInit({
+                start: start,
+                end: end,
+                value: new AST_ClassInitBlock({
+                    start: start,
+                    end: end,
+                    body: normalize_directives(M.body.map(from_moz)),
+                }),
+            });
+        },
         ForOfStatement: function(M) {
             return new (M.await ? AST_ForAwaitOf : AST_ForOf)({
                 start: my_start_token(M),
@@ -303,13 +326,22 @@
             });
         },
         ExportAllDeclaration: function(M) {
-            var alias = M.exported ? read_name(M.exported) : "*";
+            var start = my_start_token(M);
+            var end = my_end_token(M);
             return new AST_ExportForeign({
-                start: my_start_token(M),
-                end: my_end_token(M),
-                aliases: [ alias ],
-                keys: [ "*" ],
-                path: M.source.value,
+                start: start,
+                end: end,
+                aliases: [ M.exported ? from_moz_alias(M.exported) : new AST_String({
+                    start: start,
+                    value: "*",
+                    end: end,
+                }) ],
+                keys: [ new AST_String({
+                    start: start,
+                    value: "*",
+                    end: end,
+                }) ],
+                path: from_moz(M.source),
             });
         },
         ExportDefaultDeclaration: function(M) {
@@ -346,15 +378,15 @@
             if (M.source) {
                 var aliases = [], keys = [];
                 M.specifiers.forEach(function(prop) {
-                    aliases.push(read_name(prop.exported));
-                    keys.push(read_name(prop.local));
+                    aliases.push(from_moz_alias(prop.exported));
+                    keys.push(from_moz_alias(prop.local));
                 });
                 return new AST_ExportForeign({
                     start: my_start_token(M),
                     end: my_end_token(M),
                     aliases: aliases,
                     keys: keys,
-                    path: M.source.value,
+                    path: from_moz(M.source),
                 });
             }
             return new AST_ExportReferences({
@@ -362,38 +394,48 @@
                 end: my_end_token(M),
                 properties: M.specifiers.map(function(prop) {
                     var sym = new AST_SymbolExport(from_moz(prop.local));
-                    sym.alias = read_name(prop.exported);
+                    sym.alias = from_moz_alias(prop.exported);
                     return sym;
                 }),
             });
         },
         ImportDeclaration: function(M) {
+            var start = my_start_token(M);
+            var end = my_end_token(M);
             var all = null, def = null, props = null;
             M.specifiers.forEach(function(prop) {
                 var sym = new AST_SymbolImport(from_moz(prop.local));
                 switch (prop.type) {
                   case "ImportDefaultSpecifier":
                     def = sym;
-                    def.key = "";
+                    def.key = new AST_String({
+                        start: start,
+                        value: "",
+                        end: end,
+                    });
                     break;
                   case "ImportNamespaceSpecifier":
                     all = sym;
-                    all.key = "*";
+                    all.key = new AST_String({
+                        start: start,
+                        value: "*",
+                        end: end,
+                    });
                     break;
                   default:
-                    sym.key = prop.imported.name || syn.name;
+                    sym.key = from_moz_alias(prop.imported);
                     if (!props) props = [];
                     props.push(sym);
                     break;
                 }
             });
             return new AST_Import({
-                start: my_start_token(M),
-                end: my_end_token(M),
+                start: start,
+                end: end,
                 all: all,
                 default: def,
                 properties: props,
-                path: M.source.value,
+                path: from_moz(M.source),
             });
         },
         ImportExpression: function(M) {
@@ -426,7 +468,7 @@
                 end: my_end_token(M),
             };
             if (M.bigint) {
-                args.value = M.bigint.toLowerCase() + "n";
+                args.value = M.bigint.toLowerCase();
                 return new AST_BigInt(args);
             }
             var val = M.value;
@@ -599,7 +641,6 @@
     map("AssignmentPattern", AST_DefaultValue, "left>name, right>value");
     map("ConditionalExpression", AST_Conditional, "test>condition, consequent>consequent, alternate>alternative");
     map("NewExpression", AST_New, "callee>expression, arguments@args, pure=pure");
-    map("CallExpression", AST_Call, "callee>expression, arguments@args, optional=optional, pure=pure");
     map("SequenceExpression", AST_Sequence, "expressions@expressions");
     map("SpreadElement", AST_Spread, "argument>expression");
     map("ObjectExpression", AST_Object, "properties@properties");
@@ -636,6 +677,7 @@
             type: "ArrowFunctionExpression",
             async: is_async(M),
             params: params,
+            expression: !!M.value,
             body: M.value ? to_moz(M.value) : to_moz_scope("BlockStatement", M),
         };
         return {
@@ -648,6 +690,21 @@
         };
     });
 
+    def_to_moz(AST_Call, function To_Moz_CallExpression(M) {
+        var expr = M.expression;
+        if (M.args.length == 1 && expr instanceof AST_SymbolRef && expr.name == "import") return {
+            type: "ImportExpression",
+            source: to_moz(M.args[0]),
+        };
+        return {
+            type: "CallExpression",
+            callee: to_moz(expr),
+            arguments: M.args.map(to_moz),
+            optional: M.optional,
+            pure: M.pure,
+        };
+    });
+
     def_to_moz(AST_DefClass, function To_Moz_ClassDeclaration(M) {
         return {
             type: "ClassDeclaration",
@@ -714,6 +771,10 @@
         };
     });
 
+    def_to_moz(AST_ClassInit, function To_Moz_StaticBlock(M) {
+        return to_moz_scope("StaticBlock", M.value);
+    });
+
     function To_Moz_ForOfStatement(is_await) {
         return function(M) {
             return {
@@ -731,6 +792,7 @@
     def_to_moz(AST_Directive, function To_Moz_Directive(M) {
         return {
             type: "ExpressionStatement",
+            directive: M.value,
             expression: set_moz_loc(M, {
                 type: "Literal",
                 value: M.value,
@@ -751,7 +813,6 @@
             type: "TryStatement",
             block: to_moz_block(M),
             handler: to_moz(M.bcatch),
-            guardedHandlers: [],
             finalizer: to_moz(M.bfinally),
         };
     });
@@ -760,7 +821,6 @@
         return {
             type: "CatchClause",
             param: to_moz(M.argname),
-            guard: null,
             body: to_moz_block(M),
         };
     });
@@ -769,6 +829,7 @@
         return {
             type: "ExportNamedDeclaration",
             declaration: to_moz(M.body),
+            specifiers: [],
         };
     });
 
@@ -780,38 +841,26 @@
     });
 
     def_to_moz(AST_ExportForeign, function To_Moz_ExportAllDeclaration_ExportNamedDeclaration(M) {
-        if (M.keys[0] == "*") return {
+        if (M.keys[0].value == "*") return {
             type: "ExportAllDeclaration",
-            exported: M.aliases[0] == "*" ? null : {
-                type: "Identifier",
-                name: M.aliases[0],
-            },
-            source: {
-                type: "Literal",
-                value: M.path,
-            },
+            exported: M.aliases[0].value == "*" ? null : to_moz_alias(M.aliases[0]),
+            source: to_moz(M.path),
         };
         var specifiers = [];
         for (var i = 0; i < M.aliases.length; i++) {
-            specifiers.push({
+            specifiers.push(set_moz_loc({
+                start: M.keys[i].start,
+                end: M.aliases[i].end,
+            }, {
                 type: "ExportSpecifier",
-                exported: {
-                    type: "Identifier",
-                    name: M.aliases[i],
-                },
-                local: {
-                    type: "Identifier",
-                    name: M.keys[i],
-                },
-            });
+                local: to_moz_alias(M.keys[i]),
+                exported: to_moz_alias(M.aliases[i]),
+            }));
         }
         return {
             type: "ExportNamedDeclaration",
             specifiers: specifiers,
-            source: {
-                type: "Literal",
-                value: M.path,
-            },
+            source: to_moz(M.path),
         };
     });
 
@@ -819,44 +868,41 @@
         return {
             type: "ExportNamedDeclaration",
             specifiers: M.properties.map(function(prop) {
-                return {
+                return set_moz_loc({
+                    start: prop.start,
+                    end: prop.alias.end,
+                }, {
                     type: "ExportSpecifier",
                     local: to_moz(prop),
-                    exported: {
-                        type: "Identifier",
-                        name: prop.alias,
-                    },
-                };
+                    exported: to_moz_alias(prop.alias),
+                });
             }),
         };
     });
 
     def_to_moz(AST_Import, function To_Moz_ImportDeclaration(M) {
         var specifiers = M.properties ? M.properties.map(function(prop) {
-            return {
+            return set_moz_loc({
+                start: prop.key.start,
+                end: prop.end,
+            }, {
                 type: "ImportSpecifier",
                 local: to_moz(prop),
-                imported: {
-                    type: "Identifier",
-                    name: prop.key,
-                },
-            };
+                imported: to_moz_alias(prop.key),
+            });
         }) : [];
-        if (M.all) specifiers.unshift({
+        if (M.all) specifiers.unshift(set_moz_loc(M.all, {
             type: "ImportNamespaceSpecifier",
             local: to_moz(M.all),
-        });
-        if (M.default) specifiers.unshift({
+        }));
+        if (M.default) specifiers.unshift(set_moz_loc(M.default, {
             type: "ImportDefaultSpecifier",
             local: to_moz(M.default),
-        });
+        }));
         return {
             type: "ImportDeclaration",
             specifiers: specifiers,
-            source: {
-                type: "Literal",
-                value: M.path,
-            },
+            source: to_moz(M.path),
         };
     });
 
@@ -933,6 +979,8 @@
             type: "Property",
             kind: "init",
             computed: computed,
+            method: false,
+            shorthand: false,
             key: key,
             value: to_moz(M.value),
         };
@@ -969,6 +1017,7 @@
             kind: kind,
             computed: computed,
             method: M instanceof AST_ObjectMethod,
+            shorthand: false,
             key: key,
             value: to_moz(M.value),
         };
@@ -1022,8 +1071,8 @@
         var value = M.value;
         return {
             type: "Literal",
-            bigint: value.slice(0, -1),
-            raw: value,
+            bigint: value,
+            raw: value + "n",
         };
     });
 
@@ -1203,6 +1252,14 @@
         return node;
     }
 
+    function from_moz_alias(moz) {
+        return new AST_String({
+            start: my_start_token(moz),
+            value: read_name(moz),
+            end: my_end_token(moz),
+        });
+    }
+
     AST_Node.from_mozilla_ast = function(node) {
         var save_stack = FROM_MOZ_STACK;
         FROM_MOZ_STACK = [];
@@ -1254,6 +1311,13 @@
         return node != null ? node.to_mozilla_ast() : null;
     }
 
+    function to_moz_alias(alias) {
+        return is_identifier_string(alias.value) ? set_moz_loc(alias, {
+            type: "Identifier",
+            name: alias.value,
+        }) : to_moz(alias);
+    }
+
     function to_moz_block(node) {
         return {
             type: "BlockStatement",

lib/output.js

@@ -55,6 +55,7 @@ function OutputStream(options) {
         beautify         : false,
         braces           : false,
         comments         : false,
+        extendscript     : false,
         galio            : false,
         ie               : false,
         indent_level     : 4,
@@ -75,7 +76,7 @@ function OutputStream(options) {
         wrap_iife        : false,
     }, true);
 
-    // Convert comment option to RegExp if neccessary and set up comments filter
+    // Convert comment option to RegExp if necessary and set up comments filter
     var comment_filter = return_false; // Default case, throw all comments away
     if (options.comments) {
         var comments = options.comments;
@@ -406,10 +407,11 @@ function OutputStream(options) {
         print(";");
     }
 
-    function with_block(cont) {
+    function with_block(cont, end) {
         print("{");
         newline();
         with_indent(cont);
+        add_mapping(end);
         indent();
         print("}");
     }
@@ -699,6 +701,7 @@ function OutputStream(options) {
         if (p instanceof AST_Class) return true;
         // (x++)[y]
         // (typeof x).y
+        // https://github.com/mishoo/UglifyJS/issues/115
         if (p instanceof AST_PropAccess) return p.expression === this;
         // (~x)`foo`
         if (p instanceof AST_Template) return p.tag === this;
@@ -874,7 +877,9 @@ function OutputStream(options) {
         return needs_parens_assign_cond(this, output);
     });
     PARENS(AST_Conditional, function(output) {
-        return needs_parens_assign_cond(this, output);
+        return needs_parens_assign_cond(this, output)
+            // https://github.com/mishoo/UglifyJS/issues/1144
+            || output.option("extendscript") && output.parent() instanceof AST_Conditional;
     });
     PARENS(AST_Yield, function(output) {
         return needs_parens_assign_cond(this, output);
@@ -953,7 +958,7 @@ function OutputStream(options) {
         if (self.body.length > 0) {
             output.with_block(function() {
                 display_body(self.body, false, output, allow_directives);
-            });
+            }, self.end);
         } else print_braced_empty(self, output);
     }
     DEFPRINT(AST_BlockStatement, function(output) {
@@ -992,7 +997,7 @@ function OutputStream(options) {
                 if (self.init instanceof AST_Definitions) {
                     self.init.print(output);
                 } else {
-                    parenthesize_for_noin(self.init, output, true);
+                    parenthesize_for_no_in(self.init, output, true);
                 }
                 output.print(";");
                 output.space();
@@ -1061,6 +1066,14 @@ function OutputStream(options) {
         }
         output.semicolon();
     });
+    function print_alias(alias, output) {
+        var value = alias.value;
+        if (value == "*" || is_identifier_string(value)) {
+            output.print_name(value);
+        } else {
+            output.print_string(value, alias.quote);
+        }
+    }
     DEFPRINT(AST_ExportForeign, function(output) {
         var self = this;
         output.print("export");
@@ -1068,7 +1081,7 @@ function OutputStream(options) {
         var len = self.keys.length;
         if (len == 0) {
             print_braced_empty(self, output);
-        } else if (self.keys[0] == "*") {
+        } else if (self.keys[0].value == "*") {
             print_entry(0);
         } else output.with_block(function() {
             output.indent();
@@ -1080,22 +1093,22 @@ function OutputStream(options) {
                 print_entry(i);
             }
             output.newline();
-        });
+        }, self.end);
         output.space();
         output.print("from");
         output.space();
-        output.print_string(self.path, self.quote);
+        self.path.print(output);
         output.semicolon();
 
         function print_entry(index) {
             var alias = self.aliases[index];
             var key = self.keys[index];
-            output.print_name(key);
-            if (alias != key) {
+            print_alias(key, output);
+            if (alias.value != key.value) {
                 output.space();
                 output.print("as");
                 output.space();
-                output.print_name(alias);
+                print_alias(alias, output);
             }
         }
     });
@@ -1124,7 +1137,7 @@ function OutputStream(options) {
             output.print("from");
             output.space();
         }
-        output.print_string(self.path, self.quote);
+        self.path.print(output);
         output.semicolon();
     });
 
@@ -1344,7 +1357,7 @@ function OutputStream(options) {
                 if (i < last && branch.body.length > 0)
                     output.newline();
             });
-        });
+        }, self.end);
     });
     function print_branch_body(self, output) {
         output.newline();
@@ -1400,7 +1413,7 @@ function OutputStream(options) {
         print_braced(this, output);
     });
 
-    function print_definitinos(type) {
+    function print_definitions(type) {
         return function(output) {
             var self = this;
             output.print(type);
@@ -1413,15 +1426,15 @@ function OutputStream(options) {
             if (!(p instanceof AST_IterationStatement && p.init === self)) output.semicolon();
         };
     }
-    DEFPRINT(AST_Const, print_definitinos("const"));
-    DEFPRINT(AST_Let, print_definitinos("let"));
-    DEFPRINT(AST_Var, print_definitinos("var"));
+    DEFPRINT(AST_Const, print_definitions("const"));
+    DEFPRINT(AST_Let, print_definitions("let"));
+    DEFPRINT(AST_Var, print_definitions("var"));
 
-    function parenthesize_for_noin(node, output, noin) {
+    function parenthesize_for_no_in(node, output, no_in) {
         var parens = false;
         // need to take some precautions here:
         //    https://github.com/mishoo/UglifyJS/issues/60
-        if (noin) node.walk(new TreeWalker(function(node) {
+        if (no_in) node.walk(new TreeWalker(function(node) {
             if (parens) return true;
             if (node instanceof AST_Binary && node.operator == "in") return parens = true;
             if (node instanceof AST_Scope && !(is_arrow(node) && node.value)) return true;
@@ -1437,8 +1450,8 @@ function OutputStream(options) {
             output.print("=");
             output.space();
             var p = output.parent(1);
-            var noin = p instanceof AST_For || p instanceof AST_ForEnumeration;
-            parenthesize_for_noin(self.value, output, noin);
+            var no_in = p instanceof AST_For || p instanceof AST_ForEnumeration;
+            parenthesize_for_no_in(self.value, output, no_in);
         }
     });
 
@@ -1464,14 +1477,12 @@ function OutputStream(options) {
         output.print("/*@__PURE__*/");
     }
     function print_call_args(self, output) {
-        if (self.expression instanceof AST_Call || self.expression instanceof AST_Lambda) {
-            output.add_mapping(self.start);
-        }
         output.with_parens(function() {
             self.args.forEach(function(expr, i) {
                 if (i) output.comma();
                 expr.print(output);
             });
+            output.add_mapping(self.end);
         });
     }
     DEFPRINT(AST_Call, function(output) {
@@ -1506,11 +1517,12 @@ function OutputStream(options) {
         var expr = self.expression;
         expr.print(output);
         var prop = self.property;
-        if (output.option("ie") && RESERVED_WORDS[prop]) {
-            output.print(self.optional ? "?.[" : "[");
-            output.add_mapping(self.end);
-            output.print_string(prop);
-            output.print("]");
+        if (output.option("ie") && RESERVED_WORDS[prop] || self.quoted && output.option("keep_quoted_props")) {
+            if (self.optional) output.print("?.");
+            output.with_square(function() {
+                output.add_mapping(self.end);
+                output.print_string(prop);
+            });
         } else {
             if (expr instanceof AST_Number && !/[ex.)]/i.test(output.last())) output.print(".");
             output.print(self.optional ? "?." : ".");
@@ -1522,9 +1534,10 @@ function OutputStream(options) {
     DEFPRINT(AST_Sub, function(output) {
         var self = this;
         self.expression.print(output);
-        output.print(self.optional ? "?.[" : "[");
-        self.property.print(output);
-        output.print("]");
+        if (self.optional) output.print("?.");
+        output.with_square(function() {
+            self.property.print(output);
+        });
     });
     DEFPRINT(AST_Spread, function(output) {
         output.print("...");
@@ -1543,8 +1556,10 @@ function OutputStream(options) {
         exp.print(output);
     });
     DEFPRINT(AST_UnaryPostfix, function(output) {
-        this.expression.print(output);
-        output.print(this.operator);
+        var self = this;
+        self.expression.print(output);
+        output.add_mapping(self.end);
+        output.print(self.operator);
     });
     DEFPRINT(AST_Binary, function(output) {
         var self = this;
@@ -1637,7 +1652,8 @@ function OutputStream(options) {
         value.print(output);
     });
     DEFPRINT(AST_DestructuredObject, function(output) {
-        var props = this.properties, len = props.length, rest = this.rest;
+        var self = this;
+        var props = self.properties, len = props.length, rest = self.rest;
         if (len || rest) output.with_block(function() {
             props.forEach(function(prop, i) {
                 if (i) {
@@ -1657,8 +1673,8 @@ function OutputStream(options) {
                 rest.print(output);
             }
             output.newline();
-        });
-        else print_braced_empty(this, output);
+        }, self.end);
+        else print_braced_empty(self, output);
     });
     function print_properties(self, output, no_comma) {
         var props = self.properties;
@@ -1672,7 +1688,7 @@ function OutputStream(options) {
                 prop.print(output);
             });
             output.newline();
-        });
+        }, self.end);
         else print_braced_empty(self, output);
     }
     DEFPRINT(AST_Object, function(output) {
@@ -1734,19 +1750,19 @@ function OutputStream(options) {
         var name = get_symbol_name(self);
         output.print_name(name);
         var alias = self.alias;
-        if (alias != name) {
+        if (alias.value != name) {
             output.space();
             output.print("as");
             output.space();
-            output.print_name(alias);
+            print_alias(alias, output);
         }
     });
     DEFPRINT(AST_SymbolImport, function(output) {
         var self = this;
         var name = get_symbol_name(self);
         var key = self.key;
-        if (key && key != name) {
-            output.print_name(key);
+        if (key.value && key.value != name) {
+            print_alias(key, output);
             output.space();
             output.print("as");
             output.space();
@@ -1767,6 +1783,9 @@ function OutputStream(options) {
         output.print(self.strings[i]);
         output.print("`");
     });
+    DEFPRINT(AST_BigInt, function(output) {
+        output.print(this.value + "n");
+    });
     DEFPRINT(AST_Constant, function(output) {
         output.print("" + this.value);
     });
@@ -1882,7 +1901,7 @@ function OutputStream(options) {
             output.indent();
             stmt.print(output);
             output.newline();
-        });
+        }, stmt.end);
     }
 
     /* -----[ source map generators ]----- */
@@ -1905,22 +1924,27 @@ function OutputStream(options) {
     // or if we should add even more.
     DEFMAP([
         AST_Array,
+        AST_Await,
         AST_BlockStatement,
         AST_Catch,
         AST_Constant,
         AST_Debugger,
         AST_Definitions,
         AST_Destructured,
+        AST_Directive,
         AST_Finally,
         AST_Jump,
         AST_Lambda,
         AST_New,
         AST_Object,
+        AST_Spread,
         AST_StatementWithBody,
         AST_Symbol,
         AST_Switch,
         AST_SwitchBranch,
         AST_Try,
+        AST_UnaryPrefix,
+        AST_Yield,
     ], function(output) {
         output.add_mapping(this.start);
     });

lib/parse.js

@@ -207,11 +207,14 @@ function JS_Parse_Error(message, filename, line, col, pos) {
     this.line = line;
     this.col = col;
     this.pos = pos;
+    try {
+        throw new SyntaxError(message, filename, line, col);
+    } catch (cause) {
+        configure_error_stack(this, cause);
+    }
 }
-JS_Parse_Error.prototype = Object.create(Error.prototype);
+JS_Parse_Error.prototype = Object.create(SyntaxError.prototype);
 JS_Parse_Error.prototype.constructor = JS_Parse_Error;
-JS_Parse_Error.prototype.name = "SyntaxError";
-configure_error_stack(JS_Parse_Error);
 
 function js_error(message, filename, line, col, pos) {
     throw new JS_Parse_Error(message, filename, line, col, pos);
@@ -391,7 +394,8 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
         var valid = parse_js_number(num);
         if (isNaN(valid)) parse_error("Invalid syntax: " + num);
         if (has_dot || has_e || peek() != "n") return token("num", valid);
-        return token("bigint", num.toLowerCase() + next());
+        next();
+        return token("bigint", num.toLowerCase());
     }
 
     function read_escaped_char(in_string) {
@@ -552,16 +556,8 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
 
     function handle_dot() {
         next();
-        var ch = peek();
-        if (ch == ".") {
-            var op = ".";
-            do {
-                op += ".";
-                next();
-            } while (peek() == ".");
-            return token("operator", op);
-        }
-        return is_digit(ch.charCodeAt(0)) ? read_num(".") : token("punc", ".");
+        if (looking_at("..")) return token("operator", "." + next() + next());
+        return is_digit(peek().charCodeAt(0)) ? read_num(".") : token("punc", ".");
     }
 
     function read_word() {
@@ -790,7 +786,7 @@ function parse($TEXT, options) {
         else if (!optional && !can_insert_semicolon()) expect(";");
     }
 
-    function parenthesised() {
+    function parenthesized() {
         expect("(");
         var exp = expression();
         expect(")");
@@ -815,7 +811,7 @@ function parse($TEXT, options) {
         }
     }
 
-    var statement = embed_tokens(function() {
+    var statement = embed_tokens(function(toplevel) {
         handle_regexp();
         switch (S.token.type) {
           case "string":
@@ -854,15 +850,15 @@ function parse($TEXT, options) {
                 if (S.in_async) return simple_statement();
                 break;
               case "export":
+                if (!toplevel && options.module !== "") unexpected();
                 next();
                 return export_();
               case "import":
                 var token = peek();
-                if (!(token.type == "punc" && /^[(.]$/.test(token.value))) {
-                    next();
-                    return import_();
-                }
-                break;
+                if (token.type == "punc" && /^[(.]$/.test(token.value)) break;
+                if (!toplevel && options.module !== "") unexpected();
+                next();
+                return import_();
               case "let":
                 if (is_vardefs()) {
                     next();
@@ -928,18 +924,18 @@ function parse($TEXT, options) {
                 next();
                 var body = in_loop(statement);
                 expect_token("keyword", "while");
-                var condition = parenthesised();
+                var condition = parenthesized();
                 semicolon(true);
                 return new AST_Do({
                     body      : body,
-                    condition : condition
+                    condition : condition,
                 });
 
               case "while":
                 next();
                 return new AST_While({
-                    condition : parenthesised(),
-                    body      : in_loop(statement)
+                    condition : parenthesized(),
+                    body      : in_loop(statement),
                 });
 
               case "for":
@@ -967,15 +963,13 @@ function parse($TEXT, options) {
                     value = expression();
                     semicolon();
                 }
-                return new AST_Return({
-                    value: value
-                });
+                return new AST_Return({ value: value });
 
               case "switch":
                 next();
                 return new AST_Switch({
-                    expression : parenthesised(),
-                    body       : in_loop(switch_body_)
+                    expression : parenthesized(),
+                    body       : in_loop(switch_body_),
                 });
 
               case "throw":
@@ -984,9 +978,7 @@ function parse($TEXT, options) {
                     croak("Illegal newline after 'throw'");
                 var value = expression();
                 semicolon();
-                return new AST_Throw({
-                    value: value
-                });
+                return new AST_Throw({ value: value });
 
               case "try":
                 next();
@@ -1004,8 +996,8 @@ function parse($TEXT, options) {
                 }
                 next();
                 return new AST_With({
-                    expression : parenthesised(),
-                    body       : statement()
+                    expression : parenthesized(),
+                    body       : statement(),
                 });
             }
         }
@@ -1064,13 +1056,13 @@ function parse($TEXT, options) {
         return stat;
     }
 
-    function has_modifier(name) {
+    function has_modifier(name, no_nlb) {
         if (!is("name", name)) return;
         var token = peek();
         if (!token) return;
         if (is_token(token, "operator", "=")) return;
         if (token.type == "punc" && /^[(;}]$/.test(token.value)) return;
-        if (has_newline_before(token)) return;
+        if (no_nlb && has_newline_before(token)) return;
         return next();
     }
 
@@ -1100,7 +1092,7 @@ function parse($TEXT, options) {
             }
             var start = S.token;
             var fixed = !!has_modifier("static");
-            var async = has_modifier("async");
+            var async = has_modifier("async", true);
             if (is("operator", "*")) {
                 next();
                 var internal = is("name") && /^#/.test(S.token.value);
@@ -1429,41 +1421,54 @@ function parse($TEXT, options) {
     };
 
     function if_() {
-        var cond = parenthesised(), body = statement(), belse = null;
+        var cond = parenthesized(), body = statement(), alt = null;
         if (is("keyword", "else")) {
             next();
-            belse = statement();
+            alt = statement();
         }
         return new AST_If({
             condition   : cond,
             body        : body,
-            alternative : belse
+            alternative : alt,
         });
     }
 
     function is_alias() {
-        return is("name") || is_identifier_string(S.token.value);
+        return is("name") || is("string") || is_identifier_string(S.token.value);
+    }
+
+    function make_string(token) {
+        return new AST_String({
+            start: token,
+            quote: token.quote,
+            value: token.value,
+            end: token,
+        });
+    }
+
+    function as_path() {
+        var path = S.token;
+        expect_token("string");
+        semicolon();
+        return make_string(path);
     }
 
     function export_() {
         if (is("operator", "*")) {
+            var key = S.token;
+            var alias = key;
             next();
-            var alias = "*";
             if (is("name", "as")) {
                 next();
                 if (!is_alias()) expect_token("name");
-                alias = S.token.value;
+                alias = S.token;
                 next();
             }
             expect_token("name", "from");
-            var path = S.token;
-            expect_token("string");
-            semicolon();
             return new AST_ExportForeign({
-                aliases: [ alias ],
-                keys: [ "*" ],
-                path: path.value,
-                quote: path.quote,
+                aliases: [ make_string(alias) ],
+                keys: [ make_string(key) ],
+                path: as_path(),
             });
         }
         if (is("punc", "{")) {
@@ -1477,26 +1482,20 @@ function parse($TEXT, options) {
                 if (is("name", "as")) {
                     next();
                     if (!is_alias()) expect_token("name");
-                    aliases.push(S.token.value);
+                    aliases.push(S.token);
                     next();
                 } else {
-                    aliases.push(key.value);
+                    aliases.push(key);
                 }
                 if (!is("punc", "}")) expect(",");
             }
             expect("}");
             if (is("name", "from")) {
                 next();
-                var path = S.token;
-                expect_token("string");
-                semicolon();
                 return new AST_ExportForeign({
-                    aliases: aliases,
-                    keys: keys.map(function(token) {
-                        return token.value;
-                    }),
-                    path: path.value,
-                    quote: path.quote,
+                    aliases: aliases.map(make_string),
+                    keys: keys.map(make_string),
+                    path: as_path(),
                 });
             }
             semicolon();
@@ -1504,7 +1503,7 @@ function parse($TEXT, options) {
                 properties: keys.map(function(token, index) {
                     if (!is_token(token, "name")) token_error(token, "Name expected");
                     var sym = _make_symbol(AST_SymbolExport, token);
-                    sym.alias = aliases[index];
+                    sym.alias = make_string(aliases[index]);
                     return sym;
                 }),
             });
@@ -1594,26 +1593,42 @@ function parse($TEXT, options) {
         var all = null;
         var def = as_symbol(AST_SymbolImport, true);
         var props = null;
-        if (def ? (def.key = "", is("punc", ",") && next()) : !is("string")) {
+        var cont;
+        if (def) {
+            def.key = new AST_String({
+                start: def.start,
+                value: "",
+                end: def.end,
+            });
+            if (cont = is("punc", ",")) next();
+        } else {
+            cont = !is("string");
+        }
+        if (cont) {
             if (is("operator", "*")) {
+                var key = S.token;
                 next();
                 expect_token("name", "as");
                 all = as_symbol(AST_SymbolImport);
-                all.key = "*";
+                all.key = make_string(key);
             } else {
                 expect("{");
                 props = [];
                 while (is_alias()) {
                     var alias;
                     if (is_token(peek(), "name", "as")) {
-                        var key = S.token.value;
+                        var key = S.token;
                         next();
                         next();
                         alias = as_symbol(AST_SymbolImport);
-                        alias.key = key;
+                        alias.key = make_string(key);
                     } else {
                         alias = as_symbol(AST_SymbolImport);
-                        alias.key = alias.name;
+                        alias.key = new AST_String({
+                            start: alias.start,
+                            value: alias.name,
+                            end: alias.end,
+                        });
                     }
                     props.push(alias);
                     if (!is("punc", "}")) expect(",");
@@ -1622,15 +1637,11 @@ function parse($TEXT, options) {
             }
         }
         if (all || def || props) expect_token("name", "from");
-        var path = S.token;
-        expect_token("string");
-        semicolon();
         return new AST_Import({
             all: all,
             default: def,
-            path: path.value,
+            path: as_path(),
             properties: props,
-            quote: path.quote,
         });
     }
 
@@ -1808,7 +1819,7 @@ function parse($TEXT, options) {
             ret = new AST_BigInt({ value: value });
             break;
           case "string":
-            ret = new AST_String({ value : value, quote : tok.quote });
+            ret = new AST_String({ value: value, quote: tok.quote });
             break;
           case "regexp":
             ret = new AST_RegExp({ value: value });
@@ -2160,9 +2171,9 @@ function parse($TEXT, options) {
             token_error(sym.start, "Unexpected " + sym.name + " in strict mode");
     }
 
-    function as_symbol(type, noerror) {
+    function as_symbol(type, no_error) {
         if (!is("name")) {
-            if (!noerror) croak("Name expected");
+            if (!no_error) croak("Name expected");
             return null;
         }
         var sym = _make_symbol(type, S.token);
@@ -2398,20 +2409,20 @@ function parse($TEXT, options) {
         return new ctor({ operator: op, expression: expr });
     }
 
-    var expr_op = function(left, min_prec, no_in) {
+    var expr_op = function(left, min_precision, no_in) {
         var op = is("operator") ? S.token.value : null;
         if (op == "in" && no_in) op = null;
-        var prec = op != null ? PRECEDENCE[op] : null;
-        if (prec != null && prec > min_prec) {
+        var precision = op != null ? PRECEDENCE[op] : null;
+        if (precision != null && precision > min_precision) {
             next();
-            var right = expr_op(maybe_unary(no_in), op == "**" ? prec - 1 : prec, no_in);
+            var right = expr_op(maybe_unary(no_in), op == "**" ? precision - 1 : precision, no_in);
             return expr_op(new AST_Binary({
                 start    : left.start,
                 left     : left,
                 operator : op,
                 right    : right,
-                end      : right.end
-            }), min_prec, no_in);
+                end      : right.end,
+            }), min_precision, no_in);
         }
         return left;
     };
@@ -2563,7 +2574,7 @@ function parse($TEXT, options) {
         }
         S.input.push_directives_stack();
         while (!is("eof"))
-            body.push(statement());
+            body.push(statement(true));
         S.input.pop_directives_stack();
         var end = prev() || start;
         var toplevel = options.toplevel;

lib/propmangle.js

@@ -43,10 +43,11 @@
 
 "use strict";
 
-var builtins = function() {
+function get_builtins() {
     var names = new Dictionary();
-    // NaN will be included due to Number.NaN
+    // constants
     [
+        "NaN",
         "null",
         "true",
         "false",
@@ -54,37 +55,85 @@ var builtins = function() {
         "-Infinity",
         "undefined",
     ].forEach(add);
+    // global functions
     [
-        Array,
-        Boolean,
-        Date,
-        Error,
-        Function,
-        Math,
-        Number,
-        Object,
-        RegExp,
-        String,
-    ].forEach(function(ctor) {
+        "encodeURI",
+        "encodeURIComponent",
+        "escape",
+        "eval",
+        "decodeURI",
+        "decodeURIComponent",
+        "isFinite",
+        "isNaN",
+        "parseFloat",
+        "parseInt",
+        "unescape",
+    ].forEach(add);
+    // global constructors & objects
+    var global = Function("return this")();
+    [
+        "Array",
+        "ArrayBuffer",
+        "Atomics",
+        "BigInt",
+        "Boolean",
+        "console",
+        "DataView",
+        "Date",
+        "Error",
+        "Function",
+        "Int8Array",
+        "Intl",
+        "JSON",
+        "Map",
+        "Math",
+        "Number",
+        "Object",
+        "Promise",
+        "Proxy",
+        "Reflect",
+        "RegExp",
+        "Set",
+        "String",
+        "Symbol",
+        "WebAssembly",
+    ].forEach(function(name) {
+        add(name);
+        var ctor = global[name];
+        if (!ctor) return;
         Object.getOwnPropertyNames(ctor).map(add);
-        if (ctor.prototype) {
+        if (typeof ctor != "function") return;
+        if (ctor.__proto__) Object.getOwnPropertyNames(ctor.__proto__).map(add);
+        if (ctor.prototype) Object.getOwnPropertyNames(ctor.prototype).map(add);
+        try {
             Object.getOwnPropertyNames(new ctor()).map(add);
-            Object.getOwnPropertyNames(ctor.prototype).map(add);
+        } catch (e) {
+            try {
+                Object.getOwnPropertyNames(ctor()).map(add);
+            } catch (e) {}
         }
     });
-    return names;
+    return (get_builtins = function() {
+        return names.clone();
+    })();
 
     function add(name) {
         names.set(name, true);
     }
-}();
+}
 
 function reserve_quoted_keys(ast, reserved) {
     ast.walk(new TreeWalker(function(node) {
-        if (node instanceof AST_ClassProperty) {
-            if (node.start && node.start.quote) add(node.key);
-        } else if (node instanceof AST_ObjectProperty) {
-            if (node.start && node.start.quote) add(node.key);
+        if (node instanceof AST_ClassProperty
+            || node instanceof AST_DestructuredKeyVal
+            || node instanceof AST_ObjectProperty) {
+            if (node.key instanceof AST_Node) {
+                addStrings(node.key, add);
+            } else if (node.start && node.start.quote) {
+                add(node.key);
+            }
+        } else if (node instanceof AST_Dot) {
+            if (node.quoted) add(node.property);
         } else if (node instanceof AST_Sub) {
             addStrings(node.property, add);
         }
@@ -111,12 +160,16 @@ function mangle_properties(ast, options) {
         builtins: false,
         cache: null,
         debug: false,
+        domprops: false,
         keep_quoted: false,
         regex: null,
         reserved: null,
     }, true);
 
-    var reserved = options.builtins ? new Dictionary() : builtins.clone();
+    var reserved = options.builtins ? new Dictionary() : get_builtins();
+    if (!options.domprops && typeof domprops !== "undefined") domprops.forEach(function(name) {
+        reserved.set(name, true);
+    });
     if (Array.isArray(options.reserved)) options.reserved.forEach(function(name) {
         reserved.set(name, true);
     });
@@ -135,7 +188,7 @@ function mangle_properties(ast, options) {
     var regex = options.regex;
 
     // note debug is either false (disabled), or a string of the debug suffix to use (enabled).
-    // note debug may be enabled as an empty string, which is falsey. Also treat passing 'true'
+    // note debug may be enabled as an empty string, which is falsy. Also treat passing 'true'
     // the same as passing an empty string.
     var debug = options.debug !== false;
     var debug_suffix;
@@ -146,9 +199,7 @@ function mangle_properties(ast, options) {
 
     // step 1: find candidates to mangle
     ast.walk(new TreeWalker(function(node) {
-        if (node instanceof AST_Binary) {
-            if (node.operator == "in") addStrings(node.left, add);
-        } else if (node.TYPE == "Call") {
+        if (node.TYPE == "Call") {
             var exp = node.expression;
             if (exp instanceof AST_Dot) switch (exp.property) {
               case "defineProperty":
@@ -165,14 +216,18 @@ function mangle_properties(ast, options) {
                 addStrings(node.args[0], add);
                 break;
             }
-        } else if (node instanceof AST_ClassProperty) {
-            if (typeof node.key == "string") add(node.key);
+        } else if (node instanceof AST_ClassProperty
+            || node instanceof AST_DestructuredKeyVal
+            || node instanceof AST_ObjectProperty) {
+            if (node.key instanceof AST_Node) {
+                addStrings(node.key, add);
+            } else {
+                add(node.key);
+            }
         } else if (node instanceof AST_Dot) {
-            add(node.property);
-        } else if (node instanceof AST_ObjectProperty) {
-            if (typeof node.key == "string") add(node.key);
+            if (is_lhs(node, this.parent())) add(node.property);
         } else if (node instanceof AST_Sub) {
-            addStrings(node.property, add);
+            if (is_lhs(node, this.parent())) addStrings(node.property, add);
         }
     }));
 
@@ -197,12 +252,16 @@ function mangle_properties(ast, options) {
                 mangleStrings(node.args[0]);
                 break;
             }
-        } else if (node instanceof AST_ClassProperty) {
-            if (typeof node.key == "string") node.key = mangle(node.key);
+        } else if (node instanceof AST_ClassProperty
+            || node instanceof AST_DestructuredKeyVal
+            || node instanceof AST_ObjectProperty) {
+            if (node.key instanceof AST_Node) {
+                mangleStrings(node.key);
+            } else {
+                node.key = mangle(node.key);
+            }
         } else if (node instanceof AST_Dot) {
             node.property = mangle(node.property);
-        } else if (node instanceof AST_ObjectProperty) {
-            if (typeof node.key == "string") node.key = mangle(node.key);
         } else if (node instanceof AST_Sub) {
             if (!options.keep_quoted) mangleStrings(node.property);
         }
@@ -217,8 +276,14 @@ function mangle_properties(ast, options) {
     }
 
     function should_mangle(name) {
-        if (reserved.has(name)) return false;
-        if (regex && !regex.test(name)) return false;
+        if (reserved.has(name)) {
+            AST_Node.info("Preserving reserved property {this}", name);
+            return false;
+        }
+        if (regex && !regex.test(name)) {
+            AST_Node.info("Preserving excluded property {this}", name);
+            return false;
+        }
         return cache.has(name) || names_to_mangle.has(name);
     }
 
@@ -243,12 +308,16 @@ function mangle_properties(ast, options) {
             if (/^#/.test(name)) mangled = "#" + mangled;
             cache.set(name, mangled);
         }
+        AST_Node.info("Mapping property {name} to {mangled}", {
+            mangled: mangled,
+            name: name,
+        });
         return mangled;
     }
 
     function mangleStrings(node) {
         if (node instanceof AST_Sequence) {
-            mangleStrings(node.expressions.tail_node());
+            mangleStrings(node.tail_node());
         } else if (node instanceof AST_String) {
             node.value = mangle(node.value);
         } else if (node instanceof AST_Conditional) {

lib/scope.js

@@ -68,9 +68,7 @@ SymbolDef.prototype = {
         var cache = this.global && options.cache && options.cache.props;
         if (cache && cache.has(this.name)) {
             this.mangled_name = cache.get(this.name);
-        } else if (this.unmangleable(options)) {
-            names_in_use(this.scope, options).set(this.name, true);
-        } else {
+        } else if (!this.unmangleable(options)) {
             var def = this.redefined();
             if (def) {
                 this.mangled_name = def.mangled_name || def.name;
@@ -180,6 +178,13 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
             });
             return true;
         }
+        if (node instanceof AST_Switch) {
+            node.expression.walk(tw);
+            walk_scope(function() {
+                walk_body(node, tw);
+            });
+            return true;
+        }
         if (node instanceof AST_SwitchBranch) {
             node.init_vars(scope);
             descend();
@@ -286,7 +291,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
                 // ensure mangling works if `catch` reuses a scope variable
                 var redef = def.redefined();
                 if (redef) for (var s = node.scope; s; s = s.parent_scope) {
-                    push_uniq(s.enclosed, redef);
+                    if (!push_uniq(s.enclosed, redef)) break;
                     if (s === redef.scope) break;
                 }
             } else if (node instanceof AST_SymbolConst) {
@@ -369,8 +374,9 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
     // pass 3: fix up any scoping issue with IE8
     if (options.ie) self.walk(new TreeWalker(function(node) {
         if (node instanceof AST_SymbolCatch) {
-            var scope = node.thedef.defun;
-            if (scope.name instanceof AST_SymbolLambda && scope.name.name == node.name) {
+            var def = node.thedef;
+            var scope = def.defun;
+            if (def.name != "arguments" && scope.name instanceof AST_SymbolLambda && scope.name.name == def.name) {
                 scope = scope.parent_scope.resolve();
             }
             redefine(node, scope);
@@ -438,35 +444,43 @@ AST_Toplevel.DEFMETHOD("def_global", function(node) {
     }
 });
 
-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
+function init_block_vars(scope, parent, orig) {
+    // variables from this or outer scope(s) that are referenced from this or inner scopes
+    scope.enclosed = orig ? orig.enclosed.slice() : [];
+    // map name to AST_SymbolDefun (functions defined in this scope)
+    scope.functions = orig ? orig.functions.clone() : new Dictionary();
+    // map name to AST_SymbolVar (variables defined in this scope; includes functions)
+    scope.variables = orig ? orig.variables.clone() : new Dictionary();
+    if (!parent) return;
+    // top-level tracking of SymbolDef instances
+    scope.make_def = parent.make_def;
+    // the parent scope (null if this is the top level)
+    scope.parent_scope = parent;
 }
 
-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
+function init_scope_vars(scope, parent, orig) {
+    init_block_vars(scope, parent, orig);
+    // will be set to true if this or nested scope uses the global `eval`
+    scope.uses_eval = false;
+    // will be set to true if this or some nested scope uses the `with` statement
+    scope.uses_with = false;
 }
 
-AST_BlockScope.DEFMETHOD("init_vars", function(parent_scope) {
-    init_block_vars(this, parent_scope);
+AST_BlockScope.DEFMETHOD("init_vars", function(parent, orig) {
+    init_block_vars(this, parent, orig);
 });
-AST_Scope.DEFMETHOD("init_vars", function(parent_scope) {
-    init_scope_vars(this, parent_scope);
+AST_Scope.DEFMETHOD("init_vars", function(parent, orig) {
+    init_scope_vars(this, parent, orig);
 });
-AST_Arrow.DEFMETHOD("init_vars", function(parent_scope) {
-    init_scope_vars(this, parent_scope);
+AST_Arrow.DEFMETHOD("init_vars", function(parent, orig) {
+    init_scope_vars(this, parent, orig);
     return this;
 });
-AST_AsyncArrow.DEFMETHOD("init_vars", function(parent_scope) {
-    init_scope_vars(this, parent_scope);
+AST_AsyncArrow.DEFMETHOD("init_vars", function(parent, orig) {
+    init_scope_vars(this, parent, orig);
 });
-AST_Lambda.DEFMETHOD("init_vars", function(parent_scope) {
-    init_scope_vars(this, parent_scope);
+AST_Lambda.DEFMETHOD("init_vars", function(parent, orig) {
+    init_scope_vars(this, parent, orig);
     this.uses_arguments = false;
     this.def_variable(new AST_SymbolFunarg({
         name: "arguments",
@@ -480,7 +494,7 @@ AST_Lambda.DEFMETHOD("init_vars", function(parent_scope) {
 AST_Symbol.DEFMETHOD("mark_enclosed", function(options) {
     var def = this.definition();
     for (var s = this.scope; s; s = s.parent_scope) {
-        push_uniq(s.enclosed, def);
+        if (!push_uniq(s.enclosed, def)) break;
         if (!options) {
             s._var_names = undefined;
         } else {
@@ -642,8 +656,12 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
                 }, true);
             }
             var to_mangle = node.to_mangle = [];
-            node.variables.each(function(def) {
-                if (!defer_redef(def)) to_mangle.push(def);
+            node.variables.each(function(def, name) {
+                if (def.unmangleable(options)) {
+                    names_in_use(node, options).set(name, true);
+                } else if (!defer_redef(def)) {
+                    to_mangle.push(def);
+                }
             });
             descend();
             if (options.cache && node instanceof AST_Toplevel) {
@@ -704,7 +722,12 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
         }
         redefined.push(def);
         def.references.forEach(reference);
-        if (sym instanceof AST_SymbolCatch || sym instanceof AST_SymbolConst) reference(sym);
+        if (sym instanceof AST_SymbolCatch || sym instanceof AST_SymbolConst) {
+            reference(sym);
+            def.redefined = function() {
+                return redef;
+            };
+        }
         return true;
 
         function reference(sym) {

lib/utils.js

@@ -55,28 +55,41 @@ function find_if(func, array) {
     for (var i = array.length; --i >= 0;) if (func(array[i])) return array[i];
 }
 
-function configure_error_stack(fn) {
-    Object.defineProperty(fn.prototype, "stack", {
+function configure_error_stack(ex, cause) {
+    var stack = ex.name + ": " + ex.message;
+    Object.defineProperty(ex, "stack", {
         get: function() {
-            var err = new Error(this.message);
-            err.name = this.name;
-            try {
-                throw err;
-            } catch (e) {
-                return e.stack;
+            if (cause) {
+                cause.name = "" + ex.name;
+                stack = "" + cause.stack;
+                var msg = "" + cause.message;
+                cause = null;
+                var index = stack.indexOf(msg);
+                if (index < 0) {
+                    index = 0;
+                } else {
+                    index += msg.length;
+                    index = stack.indexOf("\n", index) + 1;
+                }
+                stack = stack.slice(0, index) + stack.slice(stack.indexOf("\n", index) + 1);
             }
-        }
+            return stack;
+        },
     });
 }
 
 function DefaultsError(msg, defs) {
     this.message = msg;
     this.defs = defs;
+    try {
+        throw new Error(msg);
+    } catch (cause) {
+        configure_error_stack(this, cause);
+    }
 }
 DefaultsError.prototype = Object.create(Error.prototype);
 DefaultsError.prototype.constructor = DefaultsError;
 DefaultsError.prototype.name = "DefaultsError";
-configure_error_stack(DefaultsError);
 
 function defaults(args, defs, croak) {
     if (croak) for (var i in args) {
@@ -127,8 +140,10 @@ function push_uniq(array, el) {
 
 function string_template(text, props) {
     return text.replace(/\{([^{}]+)\}/g, function(str, p) {
-        var value = props[p];
-        return value instanceof AST_Node ? value.print_to_string() : value;
+        var value = p == "this" ? props : props[p];
+        if (value instanceof AST_Node) return value.print_to_string();
+        if (value instanceof AST_Token) return value.file + ":" + value.line + "," + value.col;
+        return value;
     });
 }
 

package.json

@@ -3,7 +3,7 @@
   "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.16.1",
+  "version": "3.18.0",
   "engines": {
     "node": ">=0.8.0"
   },
@@ -23,7 +23,7 @@
     "LICENSE"
   ],
   "devDependencies": {
-    "acorn": "~8.2.1",
+    "acorn": "~8.7.1",
     "semver": "~6.3.0"
   },
   "scripts": {

test/benchmark.js

@@ -3,6 +3,7 @@
 
 "use strict";
 
+require("../tools/tty");
 var createHash = require("crypto").createHash;
 var fetch = require("./fetch");
 var spawn = require("child_process").spawn;

test/compress.js

@@ -60,8 +60,9 @@ function log() {
     console.log("%s", tmpl.apply(null, arguments));
 }
 
-function make_code(ast, options) {
+function make_code(ast, options, expression) {
     var stream = U.OutputStream(options);
+    if (expression) ast = ast.clone(true).unwrap_expression();
     ast.print(stream);
     return stream.get();
 }
@@ -69,7 +70,7 @@ function make_code(ast, options) {
 function parse_test(file) {
     var script = fs.readFileSync(file, "utf8");
     try {
-        var ast = U.parse(script, { filename: file });
+        var ast = U.parse(script, { filename: file, module: "" });
     } catch (e) {
         console.error("Caught error while parsing tests in " + file);
         console.error(e);
@@ -125,6 +126,17 @@ function parse_test(file) {
                     croak(node);
                 }
                 var name = node.left.name;
+                assert.ok([
+                    "beautify",
+                    "expression",
+                    "mangle",
+                    "options",
+                    "rename",
+                ].indexOf(name) >= 0, tmpl("Unsupported setting {name} [{line},{col}]", {
+                    name: name,
+                    line: node.start.line,
+                    col: node.start.col,
+                }));
                 test[name] = evaluate(node.right);
                 return true;
             }
@@ -178,9 +190,18 @@ function parse_test(file) {
 
 // Try to reminify original input with standard options
 // to see if it matches expect_stdout.
-function reminify(orig_options, input_code, input_formatted, stdout) {
+function reminify(expression, orig_options, input_code, input_formatted, stdout) {
     for (var i = 0; i < minify_options.length; i++) {
         var options = JSON.parse(minify_options[i]);
+        if (expression) {
+            if (!options.parse || typeof options.parse != "object") options.parse = {};
+            options.parse.expression = true;
+            if (options.compress == null) options.compress = {};
+            if (options.compress) {
+                if (typeof options.compress != "object") options.compress = {};
+                options.compress.expression = true;
+            }
+        }
         [
             "keep_fargs",
             "keep_fnames",
@@ -210,7 +231,7 @@ function reminify(orig_options, input_code, input_formatted, stdout) {
         } else {
             var toplevel = sandbox.has_toplevel(options);
             var expected = stdout[toplevel ? 1 : 0];
-            var actual = sandbox.run_code(result.code, toplevel);
+            var actual = run_code(expression, result.code, toplevel);
             if (typeof expected != "string" && typeof actual != "string" && expected.name == actual.name) {
                 actual = expected;
             }
@@ -245,18 +266,25 @@ function reminify(orig_options, input_code, input_formatted, stdout) {
     return true;
 }
 
+function run_code(expression, code, toplevel) {
+    return sandbox.run_code(expression ? "console.log(" + 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) {
-        expect = make_code(to_toplevel(test.expect, test.mangle), output_options);
+        expect = to_toplevel(test.expect, test.mangle, test.expression);
+        expect = make_code(expect, output_options, test.expression);
     } else {
         expect = test.expect_exact;
     }
-    var input = to_toplevel(test.input, test.mangle);
-    var input_code = make_code(input);
+    var input = to_toplevel(test.input, test.mangle, test.expression);
+    var input_code = make_code(input, {
+        keep_quoted_props: true,
+    }, test.expression);
     var input_formatted = make_code(test.input, {
         annotations: true,
         beautify: true,
@@ -266,7 +294,7 @@ function test_case(test) {
     });
     try {
         input.validate_ast();
-        U.parse(input_code);
+        U.parse(input_code, { expression: test.expression });
     } catch (ex) {
         log([
             "!!! Cannot parse input",
@@ -292,8 +320,9 @@ function test_case(test) {
             warnings_emitted.push(text);
         }, /"INFO: /.test(expected_warnings));
     }
+    var quoted_props;
     if (test.mangle && test.mangle.properties && test.mangle.properties.keep_quoted) {
-        var quoted_props = test.mangle.properties.reserved;
+        quoted_props = test.mangle.properties.reserved;
         if (!Array.isArray(quoted_props)) quoted_props = [];
         test.mangle.properties.reserved = quoted_props;
         U.reserve_quoted_keys(input, quoted_props);
@@ -308,9 +337,10 @@ function test_case(test) {
     if (test.mangle) {
         output.compute_char_frequency(test.mangle);
         output.mangle_names(test.mangle);
+        if (quoted_props) U.reserve_quoted_keys(input, quoted_props);
         if (test.mangle.properties) U.mangle_properties(output, test.mangle.properties);
     }
-    var output_code = make_code(output, output_options);
+    var output_code = make_code(output, output_options, test.expression);
     U.AST_Node.log_function();
     if (expect != output_code) {
         log([
@@ -333,7 +363,7 @@ function test_case(test) {
     // expect == output
     try {
         output.validate_ast();
-        U.parse(output_code);
+        U.parse(output_code, { expression: test.expression });
     } catch (ex) {
         log([
             "!!! Test matched expected result but cannot parse output",
@@ -377,7 +407,7 @@ function test_case(test) {
         }
     }
     if (test.expect_stdout && (!test.node_version || semver.satisfies(process.version, test.node_version))) {
-        var stdout = [ sandbox.run_code(input_code), sandbox.run_code(input_code, true) ];
+        var stdout = [ run_code(test.expression, input_code), run_code(test.expression, input_code, true) ];
         var toplevel = sandbox.has_toplevel({
             compress: test.options,
             mangle: test.mangle
@@ -406,7 +436,7 @@ function test_case(test) {
             });
             return false;
         }
-        actual = sandbox.run_code(output_code, toplevel);
+        actual = run_code(test.expression, output_code, toplevel);
         if (!sandbox.same_stdout(test.expect_stdout, actual)) {
             log([
                 "!!! failed",
@@ -427,7 +457,7 @@ function test_case(test) {
             });
             return false;
         }
-        if (!reminify(test.options, input_code, input_formatted, stdout)) {
+        if (!reminify(test.expression, test.options, input_code, input_formatted, stdout)) {
             return false;
         }
     }
@@ -438,20 +468,30 @@ function tmpl() {
     return U.string_template.apply(null, arguments);
 }
 
-function to_toplevel(input, mangle_options) {
+function to_toplevel(input, mangle_options, expression) {
     if (!(input instanceof U.AST_BlockStatement)) throw new Error("Unsupported input syntax");
-    var directive = true;
     var offset = input.start.line;
     var tokens = [];
-    var toplevel = new U.AST_Toplevel(input.transform(new U.TreeTransformer(function(node) {
+    input.walk(new U.TreeWalker(function(node) {
         if (U.push_uniq(tokens, node.start)) node.start.line -= offset;
-        if (!directive || node === input) return;
-        if (node instanceof U.AST_SimpleStatement && node.body instanceof U.AST_String) {
-            return new U.AST_Directive(node.body);
-        } else {
+        if (U.push_uniq(tokens, node.end)) node.end.line -= offset;
+    }));
+    var toplevel;
+    if (!expression) {
+        var directive = true;
+        toplevel = new U.AST_Toplevel(input.transform(new U.TreeTransformer(function(node) {
+            if (!directive) return node;
+            if (node === input) return;
+            if (node instanceof U.AST_SimpleStatement && node.body instanceof U.AST_String) {
+                return new U.AST_Directive(node.body);
+            }
             directive = false;
-        }
-    })));
+        })));
+    } else if (input.body.length == 1) {
+        toplevel = input.body[0].wrap_expression();
+    } else {
+        throw new Error("Invalid expression");
+    }
     toplevel.figure_out_scope(mangle_options);
     return toplevel;
 }

test/compress/arrows.js

@@ -668,6 +668,87 @@ single_use_recursive: {
     node_version: ">=4"
 }
 
+inline_iife_within_arrow: {
+    options = {
+        arrows: true,
+        inline: true,
+    }
+    input: {
+        var f = () => console.log(function(a) {
+            return Math.ceil(a);
+        }(Math.random()));
+        f();
+    }
+    expect: {
+        var f = () => {
+            return console.log((a = Math.random(), Math.ceil(a)));
+            var a;
+        };
+        f();
+    }
+    expect_stdout: "1"
+    node_version: ">=4"
+}
+
+instanceof_lambda_1: {
+    options = {
+        evaluate: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(42 instanceof (() => {}));
+    }
+    expect: {
+        console.log(false);
+    }
+    expect_stdout: "false"
+    node_version: ">=4"
+}
+
+instanceof_lambda_2: {
+    options = {
+        evaluate: true,
+        side_effects: false,
+    }
+    input: {
+        console.log(null instanceof (() => {}));
+    }
+    expect: {
+        console.log((null, () => {}, false));
+    }
+    expect_stdout: "false"
+    node_version: ">=4"
+}
+
+instanceof_lambda_3: {
+    options = {
+        evaluate: true,
+        side_effects: true,
+    }
+    input: {
+        console.log({} instanceof (() => {}));
+    }
+    expect: {
+        console.log({} instanceof (() => {}));
+    }
+    expect_stdout: TypeError("Function has non-object prototype 'undefined' in instanceof check")
+    node_version: ">=4"
+}
+
+instanceof_lambda_4: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        ({ p: "foo" }) instanceof (() => {});
+    }
+    expect: {
+        [] instanceof (() => {});
+    }
+    expect_stdout: TypeError("Function has non-object prototype 'undefined' in instanceof check")
+    node_version: ">=4"
+}
+
 issue_4388: {
     options = {
         inline: true,
@@ -1073,7 +1154,7 @@ issue_5414_2: {
     node_version: ">=4"
 }
 
-issue_5416: {
+issue_5416_1: {
     options = {
         dead_code: true,
         evaluate: true,
@@ -1095,10 +1176,11 @@ issue_5416: {
     expect: {
         var f = () => {
             {
-                arguments = void 0;
                 console;
+                arguments = void 0,
                 console.log(arguments);
                 var arguments;
+                return;
             }
         };
         f();
@@ -1107,6 +1189,97 @@ issue_5416: {
     node_version: ">=4"
 }
 
+issue_5416_2: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        inline: true,
+        loops: true,
+        unused: true,
+    }
+    input: {
+        var f = () => {
+            while ((() => {
+                console;
+                var a = function g(arguments) {
+                    while (console.log(arguments));
+                }();
+            })());
+        };
+        f();
+    }
+    expect: {
+        var f = () => {
+            {
+                console;
+                var arguments = void 0;
+                for (; console.log(arguments););
+                return;
+            }
+        };
+        f();
+    }
+    expect_stdout: "undefined"
+    node_version: ">=4"
+}
+
+issue_5416_3: {
+    options = {
+        inline: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var f = () => {
+            (() => {
+                var a = function g(arguments) {
+                    console.log(arguments);
+                }();
+            })();
+        };
+        f();
+    }
+    expect: {
+        var f = () => {
+            arguments = void 0,
+            console.log(arguments);
+            var arguments;
+        };
+        f();
+    }
+    expect_stdout: "undefined"
+    node_version: ">=4"
+}
+
+issue_5416_4: {
+    options = {
+        arrows: true,
+        inline: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var f = () => {
+            (() => {
+                var a = function g(arguments) {
+                    while (console.log(arguments));
+                }();
+            })();
+        };
+        f();
+    }
+    expect: {
+        var f = () => {
+            var arguments = void 0;
+            while (console.log(arguments));
+            return;
+        };
+        f();
+    }
+    expect_stdout: "undefined"
+    node_version: ">=4"
+}
+
 issue_5495: {
     input: {
         console.log((() => {
@@ -1120,3 +1293,28 @@ issue_5495: {
     expect_stdout: "undefined"
     node_version: ">=4"
 }
+
+issue_5653: {
+    options = {
+        arrows: true,
+        hoist_props: true,
+        passes: 2,
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        console.log((a => {
+            a = { p: console };
+            return a++;
+        })());
+    }
+    expect: {
+        console.log((a => {
+            return +{};
+        })());
+    }
+    expect_stdout: "NaN"
+    node_version: ">=4"
+}

test/compress/assignments.js

@@ -290,6 +290,45 @@ increment_decrement_2: {
     expect_stdout: "42"
 }
 
+lazily_chained_assignments: {
+    options = {
+        assignments: true,
+        collapse_vars: true,
+        conditionals: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            if (a = console.log("foo"))
+                a = console.log("bar");
+            return a;
+        }
+        function g(b) {
+            if (b = console.log("baz"))
+                ;
+            else
+                b = console.log("moo");
+            return b;
+        }
+        console.log(f(), g());
+    }
+    expect: {
+        function f(a) {
+            return console.log("foo") && console.log("bar");
+        }
+        function g(b) {
+            return console.log("baz") || console.log("moo");
+        }
+        console.log(f(), g());
+    }
+    expect_stdout: [
+        "foo",
+        "baz",
+        "moo",
+        "undefined undefined",
+    ]
+}
+
 issue_3375_1: {
     options = {
         assignments: true,
@@ -803,3 +842,23 @@ issue_4924_2: {
     expect_stdout: "PASS"
     node_version: ">=15"
 }
+
+issue_5670: {
+    options = {
+        assignments: true,
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        (function(a, b) {
+            a && a && (a = b += "") || console.log("PASS");
+        })();
+    }
+    expect: {
+        (function(a, b) {
+            a = a,
+            console.log("PASS");
+        })();
+    }
+    expect_stdout: "PASS"
+}

test/compress/awaits.js

@@ -529,6 +529,7 @@ inline_block_await: {
 
 inline_block_await_async: {
     options = {
+        awaits: true,
         inline: true,
     }
     input: {
@@ -1046,6 +1047,60 @@ collapse_vars_3: {
     node_version: ">=8"
 }
 
+collapse_funarg_1: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        A = "FAIL";
+        var a = "PASS";
+        (async function({}, b) {
+            return b;
+        })(null, A = a);
+        console.log(A);
+    }
+    expect: {
+        A = "FAIL";
+        var a = "PASS";
+        (async function({}, b) {
+            return b;
+        })(null, A = a);
+        console.log(A);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
+collapse_funarg_2: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        A = "FAIL";
+        B = "PASS";
+        (async function() {
+            console.log(function({}, a) {
+                return a;
+            }(null, A = B));
+        })();
+        console.log(A);
+    }
+    expect: {
+        A = "FAIL";
+        B = "PASS";
+        (async function() {
+            console.log(function({}, a) {
+                return a;
+            }(null, A = B));
+        })();
+        console.log(A);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8"
+}
+
 collapse_property_lambda: {
     options = {
         collapse_vars: true,
@@ -1293,7 +1348,7 @@ functions_inner_var: {
     node_version: ">=8"
 }
 
-instanceof_lambda: {
+instanceof_lambda_1: {
     options = {
         evaluate: true,
         side_effects: true,
@@ -1308,6 +1363,50 @@ instanceof_lambda: {
     node_version: ">=8"
 }
 
+instanceof_lambda_2: {
+    options = {
+        evaluate: true,
+        side_effects: false,
+    }
+    input: {
+        console.log(null instanceof async function() {});
+    }
+    expect: {
+        console.log((null, async function() {}, false));
+    }
+    expect_stdout: "false"
+    node_version: ">=8"
+}
+
+instanceof_lambda_3: {
+    options = {
+        evaluate: true,
+        side_effects: true,
+    }
+    input: {
+        console.log({} instanceof async function() {});
+    }
+    expect: {
+        console.log({} instanceof async function() {});
+    }
+    expect_stdout: TypeError("Function has non-object prototype 'undefined' in instanceof check")
+    node_version: ">=8"
+}
+
+instanceof_lambda_4: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        ({ p: "foo" }) instanceof async function() {};
+    }
+    expect: {
+        [] instanceof async function() {};
+    }
+    expect_stdout: TypeError("Function has non-object prototype 'undefined' in instanceof check")
+    node_version: ">=8"
+}
+
 issue_4335_1: {
     options = {
         inline: true,
@@ -2693,6 +2792,7 @@ issue_5177: {
 
 issue_5250: {
     options = {
+        awaits: true,
         inline: true,
     }
     input: {
@@ -2801,6 +2901,7 @@ issue_5298: {
 
 issue_5305_1: {
     options = {
+        awaits: true,
         inline: true,
     }
     input: {
@@ -2834,6 +2935,7 @@ issue_5305_1: {
 
 issue_5305_2: {
     options = {
+        awaits: true,
         inline: true,
     }
     input: {
@@ -3021,3 +3123,585 @@ issue_5506: {
     expect_stdout: "PASS"
     node_version: ">=8"
 }
+
+issue_5528_1: {
+    options = {
+        awaits: true,
+        inline: true,
+    }
+    input: {
+        (async function() {
+            await function() {
+                try {
+                    return;
+                } finally {
+                    console.log("foo");
+                }
+            }();
+        })();
+        console.log("bar");
+    }
+    expect: {
+        (async function() {
+            await function() {
+                try {
+                    return;
+                } finally {
+                    console.log("foo");
+                }
+            }();
+        })();
+        console.log("bar");
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=8"
+}
+
+issue_5528_2: {
+    options = {
+        awaits: true,
+        inline: true,
+    }
+    input: {
+        (async function() {
+            await function() {
+                try {
+                    return 42;
+                } finally {
+                    console.log("foo");
+                }
+            }();
+        })();
+        console.log("bar");
+    }
+    expect: {
+        (async function() {
+            await function() {
+                try {
+                    return 42;
+                } finally {
+                    console.log("foo");
+                }
+            }();
+        })();
+        console.log("bar");
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=8"
+}
+
+issue_5528_3: {
+    options = {
+        awaits: true,
+        inline: true,
+    }
+    input: {
+        (async function() {
+            await function() {
+                try {
+                    FAIL;
+                } catch (e) {
+                    return console.log("foo");
+                } finally {
+                    console.log("bar");
+                }
+            }();
+        })();
+        console.log("baz");
+    }
+    expect: {
+        (async function() {
+            await function() {
+                try {
+                    FAIL;
+                } catch (e) {
+                    return console.log("foo");
+                } finally {
+                    console.log("bar");
+                }
+            }();
+        })();
+        console.log("baz");
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+        "baz",
+    ]
+    node_version: ">=8"
+}
+
+issue_5528_4: {
+    options = {
+        awaits: true,
+        inline: true,
+    }
+    input: {
+        (async function() {
+            await function() {
+                try {
+                    return {
+                        then() {
+                            console.log("foo");
+                        },
+                    };
+                } finally {
+                    console.log("bar");
+                }
+            }();
+        })();
+        console.log("baz");
+    }
+    expect: {
+        (async function() {
+            await function() {
+                try {
+                    return {
+                        then() {
+                            console.log("foo");
+                        },
+                    };
+                } finally {
+                    console.log("bar");
+                }
+            }();
+        })();
+        console.log("baz");
+    }
+    expect_stdout: [
+        "bar",
+        "baz",
+        "foo",
+    ]
+    node_version: ">=8"
+}
+
+issue_5634_1: {
+    options = {
+        awaits: true,
+        inline: true,
+    }
+    input: {
+        var a = "foo";
+        (async function() {
+            (async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            console.log("bar");
+                            resolve();
+                            console.log("baz");
+                        },
+                    };
+                } finally {
+                    a = "moo";
+                }
+            })();
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "foo";
+        (async function() {
+            (async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            console.log("bar");
+                            resolve();
+                            console.log("baz");
+                        },
+                    };
+                } finally {
+                    a = "moo";
+                }
+            })();
+        })();
+        console.log(a);
+    }
+    expect_stdout: [
+        "moo",
+        "bar",
+        "baz",
+    ]
+    node_version: ">=8"
+}
+
+issue_5634_1_side_effects: {
+    options = {
+        awaits: true,
+        inline: true,
+        side_effects: true,
+    }
+    input: {
+        var a = "foo";
+        (async function() {
+            (async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            console.log("bar");
+                            resolve();
+                            console.log("baz");
+                        },
+                    };
+                } finally {
+                    a = "moo";
+                }
+            })();
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "foo";
+        (async function() {
+            try {
+                return {
+                    then(resolve) {
+                        console.log("bar");
+                        resolve();
+                        console.log("baz");
+                    },
+                };
+            } finally {
+                a = "moo";
+            }
+        })();
+        console.log(a);
+    }
+    expect_stdout: [
+        "moo",
+        "bar",
+        "baz",
+    ]
+    node_version: ">=8"
+}
+
+issue_5634_2: {
+    options = {
+        awaits: true,
+        inline: true,
+    }
+    input: {
+        var a = "foo";
+        (async function() {
+            await async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            console.log("bar");
+                            resolve();
+                            console.log("baz");
+                        },
+                    };
+                } finally {
+                    a = "moo";
+                }
+            }();
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "foo";
+        (async function() {
+            await async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            console.log("bar");
+                            resolve();
+                            console.log("baz");
+                        },
+                    };
+                } finally {
+                    a = "moo";
+                }
+            }();
+        })();
+        console.log(a);
+    }
+    expect_stdout: [
+        "moo",
+        "bar",
+        "baz",
+    ]
+    node_version: ">=8"
+}
+
+issue_5634_2_side_effects: {
+    options = {
+        awaits: true,
+        inline: true,
+        side_effects: true,
+    }
+    input: {
+        var a = "foo";
+        (async function() {
+            await async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            console.log("bar");
+                            resolve();
+                            console.log("baz");
+                        },
+                    };
+                } finally {
+                    a = "moo";
+                }
+            }();
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "foo";
+        (async function() {
+            try {
+                return {
+                    then(resolve) {
+                        console.log("bar");
+                        resolve();
+                        console.log("baz");
+                    },
+                };
+            } finally {
+                a = "moo";
+            }
+        })();
+        console.log(a);
+    }
+    expect_stdout: [
+        "moo",
+        "bar",
+        "baz",
+    ]
+    node_version: ">=8"
+}
+
+issue_5634_3: {
+    options = {
+        awaits: true,
+        inline: true,
+    }
+    input: {
+        var a = "foo";
+        (async function() {
+            return async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            console.log("bar");
+                            resolve();
+                            console.log("baz");
+                        },
+                    };
+                } finally {
+                    a = "moo";
+                }
+            }();
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "foo";
+        (async function() {
+            return async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            console.log("bar");
+                            resolve();
+                            console.log("baz");
+                        },
+                    };
+                } finally {
+                    a = "moo";
+                }
+            }();
+        })();
+        console.log(a);
+    }
+    expect_stdout: [
+        "moo",
+        "bar",
+        "baz",
+    ]
+    node_version: ">=8"
+}
+
+issue_5634_3_side_effects: {
+    options = {
+        awaits: true,
+        inline: true,
+        side_effects: true,
+    }
+    input: {
+        var a = "foo";
+        (async function() {
+            return async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            console.log("bar");
+                            resolve();
+                            console.log("baz");
+                        },
+                    };
+                } finally {
+                    a = "moo";
+                }
+            }();
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "foo";
+        (async function() {
+            try {
+                return {
+                    then(resolve) {
+                        console.log("bar");
+                        resolve();
+                        console.log("baz");
+                    },
+                };
+            } finally {
+                a = "moo";
+            }
+        })();
+        console.log(a);
+    }
+    expect_stdout: [
+        "moo",
+        "bar",
+        "baz",
+    ]
+    node_version: ">=8"
+}
+
+issue_5692_1: {
+    options = {
+        awaits: true,
+        inline: true,
+    }
+    input: {
+        (async function() {
+            (async function() {
+                for await (var k of []);
+            })();
+            console.log("foo");
+        })();
+        console.log("bar");
+    }
+    expect: {
+        (async function() {
+            (async function() {
+                for await (var k of []);
+            })();
+            console.log("foo");
+        })();
+        console.log("bar");
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=10"
+}
+
+issue_5692_2: {
+    options = {
+        awaits: true,
+        inline: true,
+    }
+    input: {
+        (async function() {
+            (async function() {
+                for (var k of []);
+            })();
+            console.log("foo");
+        })();
+        console.log("bar");
+    }
+    expect: {
+        (async function() {
+            for (var k of []);
+            console.log("foo");
+        })();
+        console.log("bar");
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=8"
+}
+
+issue_5791: {
+    options = {
+        awaits: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        (async function() {
+            async function f() {
+                try {
+                    await {
+                        then(resolve) {
+                            setImmediate(() => {
+                                console.log("foo");
+                                resolve();
+                            });
+                        },
+                    };
+                } catch (e) {
+                    console.log("FAIL", e);
+                }
+            }
+            async function g() {
+                try {
+                    await f();
+                } catch (e) {}
+            }
+            await g();
+            console.log("bar");
+        })();
+    }
+    expect: {
+        (async function() {
+            await async function() {
+                try {
+                    await async function() {
+                        try {
+                            await {
+                                then(resolve) {
+                                    setImmediate(() => {
+                                        console.log("foo");
+                                        resolve();
+                                    });
+                                },
+                            };
+                        } catch (e) {
+                            console.log("FAIL", e);
+                        }
+                    }();
+                } catch (e) {}
+            }();
+            console.log("bar");
+        })();
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=8"
+}

test/compress/bigint.js

@@ -90,3 +90,17 @@ issue_4801: {
     expect_stdout: "PASS"
     node_version: ">=10.4.0"
 }
+
+issue_5728: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log("" + 4n + 2);
+    }
+    expect: {
+        console.log("42");
+    }
+    expect_stdout: "42"
+    node_version: ">=10.4.0"
+}

test/compress/blocks.js

@@ -47,3 +47,45 @@ keep_some_blocks: {
         } else stuff();
     }
 }
+
+issue_1666: {
+    input: {
+        var a = 42;
+        {
+            function a() {}
+            a();
+        }
+        console.log("PASS");
+    }
+    expect: {
+        var a = 42;
+        {
+            function a() {}
+            a();
+        }
+        console.log("PASS");
+    }
+    expect_stdout: true
+}
+
+issue_1666_strict: {
+    input: {
+        "use strict";
+        var a = 42;
+        {
+            function a() {}
+            a();
+        }
+        console.log("PASS");
+    }
+    expect: {
+        "use strict";
+        var a = 42;
+        {
+            function a() {}
+            a();
+        }
+        console.log("PASS");
+    }
+    expect_stdout: true
+}

test/compress/booleans.js

@@ -80,6 +80,25 @@ de_morgan_1c: {
     expect_stdout: "true"
 }
 
+de_morgan_1d: {
+    options = {
+        booleans: true,
+    }
+    input: {
+        function f(a) {
+            return (a = false) || a;
+        }
+        console.log(f(null), f(42));
+    }
+    expect: {
+        function f(a) {
+            return a = !1;
+        }
+        console.log(f(null), f(42));
+    }
+    expect_stdout: "false false"
+}
+
 de_morgan_2a: {
     options = {
         booleans: true,
@@ -181,6 +200,31 @@ de_morgan_2d: {
     ]
 }
 
+de_morgan_2e: {
+    options = {
+        booleans: true,
+        conditionals: true,
+    }
+    input: {
+        function f(a, b) {
+            return (a && b) && b;
+        }
+        console.log(f(null), f(null, {}));
+        console.log(f(42), f(42, {}));
+    }
+    expect: {
+        function f(a, b) {
+            return a && b;
+        }
+        console.log(f(null), f(null, {}));
+        console.log(f(42), f(42, {}));
+    }
+    expect_stdout: [
+        "null null",
+        "undefined {}",
+    ]
+}
+
 de_morgan_3a: {
     options = {
         booleans: true,
@@ -786,3 +830,37 @@ issue_5469: {
     }
     expect_stdout: "undefined"
 }
+
+issue_5694_1: {
+    options = {
+        booleans: true,
+        conditionals: true,
+    }
+    input: {
+        var Infinity;
+        // Node.js v0.12~6 (vm): 42
+        console.log((Infinity = 42) && Infinity);
+    }
+    expect: {
+        var Infinity;
+        console.log((Infinity = 42) && Infinity);
+    }
+    expect_stdout: true
+}
+
+issue_5694_2: {
+    options = {
+        booleans: true,
+        conditionals: true,
+    }
+    input: {
+        var undefined;
+        // Node.js v0.12~6 (vm): NaN
+        console.log(("foo", ++undefined) || undefined);
+    }
+    expect: {
+        var undefined;
+        console.log(("foo", ++undefined) || undefined);
+    }
+    expect_stdout: true
+}

test/compress/classes.js

@@ -241,6 +241,94 @@ class_super: {
     node_version: ">=4"
 }
 
+static_newline_1: {
+    input: {
+        class A {
+            static
+            P
+        }
+        console.log("P" in A, "static" in A);
+        console.log("P" in new A(), "static" in new A());
+    }
+    expect_exact: 'class A{static P}console.log("P"in A,"static"in A);console.log("P"in new A,"static"in new A);'
+    expect_stdout: [
+        "true false",
+        "false false",
+    ]
+    node_version: ">=12"
+}
+
+static_newline_2: {
+    input: {
+        class A {
+            static
+            static
+            P
+        }
+        console.log("P" in A, "static" in A);
+        console.log("P" in new A(), "static" in new A());
+    }
+    expect_exact: 'class A{static static;P}console.log("P"in A,"static"in A);console.log("P"in new A,"static"in new A);'
+    expect_stdout: [
+        "false true",
+        "true false",
+    ]
+    node_version: ">=12"
+}
+
+static_newline_3: {
+    input: {
+        class A {
+            static
+            static
+            static
+            P
+        }
+        console.log("P" in A, "static" in A);
+        console.log("P" in new A(), "static" in new A());
+    }
+    expect_exact: 'class A{static static;static P}console.log("P"in A,"static"in A);console.log("P"in new A,"static"in new A);'
+    expect_stdout: [
+        "true true",
+        "false false",
+    ]
+    node_version: ">=12"
+}
+
+static_newline_4: {
+    input: {
+        class A {
+            static
+            static
+            static
+            static
+            P
+        }
+        console.log("P" in A, "static" in A);
+        console.log("P" in new A(), "static" in new A());
+    }
+    expect_exact: 'class A{static static;static static;P}console.log("P"in A,"static"in A);console.log("P"in new A,"static"in new A);'
+    expect_stdout: [
+        "false true",
+        "true false",
+    ]
+    node_version: ">=12"
+}
+
+static_newline_init: {
+    input: {
+        class A {
+            static
+            {
+                console.log("PASS");
+            }
+        }
+    }
+    expect_exact: 'class A{static{console.log("PASS")}}'
+    expect_stdout: "PASS"
+    node_version: ">=16"
+}
+
 static_init: {
     input: {
         var a = "foo";
@@ -511,6 +599,7 @@ drop_extends: {
         inline: true,
         passes: 2,
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         side_effects: true,
@@ -658,6 +747,56 @@ separate_name: {
     node_version: ">=4"
 }
 
+static_getter: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+    }
+    input: {
+        "use strict";
+        (class {
+            static get p() {
+                console.log("PASS");
+            };
+        }).p;
+    }
+    expect: {
+        "use strict";
+        (class {
+            static get p() {
+                console.log("PASS");
+            };
+        }).p;
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+static_setter: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+    }
+    input: {
+        "use strict";
+        (class {
+            static set p(v) {
+                console.log(v);
+            };
+        }).p = "PASS";
+    }
+    expect: {
+        "use strict";
+        (class {
+            static set p(v) {
+                console.log(v);
+            };
+        }).p = "PASS";
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
 static_side_effects: {
     options = {
         inline: true,
@@ -783,6 +922,7 @@ single_use_3: {
 
 single_use_4: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -1025,9 +1165,9 @@ collapse_rhs_static: {
         "use strict";
         var a = "FAIL";
         class A {
-            static p = a = "PASS";
+            static p = "PASS";
         }
-        console.log(a);
+        console.log(a = "PASS");
     }
     expect_stdout: "PASS"
     node_version: ">=12"
@@ -1365,6 +1505,218 @@ keep_instanceof_3: {
     node_version: ">=4"
 }
 
+keep_field_reference_1: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        function f() {}
+        class A {
+            p = f;
+        }
+        console.log(new A().p === new A().p ? "PASS" : "FAIL");
+    }
+    expect: {
+        "use strict";
+        function f() {}
+        class A {
+            p = f;
+        }
+        console.log(new A().p === new A().p ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=12"
+}
+
+keep_field_reference_2: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        function f() {}
+        var A = class {
+            p = f;
+        };
+        console.log(new A().p === new A().p ? "PASS" : "FAIL");
+    }
+    expect: {
+        "use strict";
+        function f() {}
+        var A = class {
+            p = f;
+        };
+        console.log(new A().p === new A().p ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=12"
+}
+
+keep_field_reference_3: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        class A {}
+        class B {
+            p = A;
+        }
+        console.log(new B().p === new B().p ? "PASS" : "FAIL");
+    }
+    expect: {
+        "use strict";
+        class A {}
+        class B {
+            p = A;
+        }
+        console.log(new B().p === new B().p ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=12"
+}
+
+keep_field_reference_4: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        var A = class {};
+        var B = class {
+            p = A;
+        };
+        console.log(new B().p === new B().p ? "PASS" : "FAIL");
+    }
+    expect: {
+        "use strict";
+        var A = class {};
+        var B = class {
+            p = A;
+        };
+        console.log(new B().p === new B().p ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=12"
+}
+
+keep_static_field_reference_1: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        function f() {}
+        class A {
+            static P = f;
+        }
+        console.log(A.P === A.P ? "PASS" : "FAIL");
+    }
+    expect: {
+        "use strict";
+        class A {
+            static P = function() {};
+        }
+        console.log(A.P === A.P ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=12"
+}
+
+keep_static_field_reference_2: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        function f() {}
+        var A = class {
+            static P = f;
+        };
+        console.log(A.P === A.P ? "PASS" : "FAIL");
+    }
+    expect: {
+        "use strict";
+        var A = class {
+            static P = function() {};
+        };
+        console.log(A.P === A.P ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=12"
+}
+
+keep_static_field_reference_3: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        class A {}
+        class B {
+            static P = A;
+        }
+        console.log(B.P === B.P ? "PASS" : "FAIL");
+    }
+    expect: {
+        "use strict";
+        class B {
+            static P = class {};
+        }
+        console.log(B.P === B.P ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=12"
+}
+
+keep_static_field_reference_4: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        var A = class {};
+        var B = class {
+            static P = A;
+        };
+        console.log(B.P === B.P ? "PASS" : "FAIL");
+    }
+    expect: {
+        "use strict";
+        var B = class {
+            static P = class {};
+        };
+        console.log(B.P === B.P ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=12"
+}
+
 issue_805_1: {
     options = {
         inline: true,
@@ -2026,6 +2378,7 @@ issue_4829_2: {
 mangle_properties: {
     mangle = {
         properties: {
+            domprops: true,
             keep_quoted: true,
         },
     }
@@ -2062,6 +2415,14 @@ mangle_properties: {
         console.log(A.s, new A().e);
     }
     expect_stdout: "PASS 42"
+    expect_warnings: [
+        "INFO: Preserving reserved property q",
+        "INFO: Mapping property #P to #t",
+        "INFO: Mapping property Q to s",
+        "INFO: Mapping property #p to #i",
+        "INFO: Mapping property r to e",
+        "INFO: Preserving reserved property log",
+    ]
     node_version: ">=14.6"
 }
 
@@ -2166,6 +2527,7 @@ issue_4962_1: {
     options = {
         ie: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2197,6 +2559,7 @@ issue_4962_1_strict: {
     options = {
         ie: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2224,6 +2587,7 @@ issue_4962_1_strict_direct: {
     options = {
         ie: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2255,6 +2619,7 @@ issue_4962_2: {
     options = {
         ie: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2286,6 +2651,7 @@ issue_4962_2_strict: {
     options = {
         ie: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2314,6 +2680,7 @@ issue_4962_2_strict_direct: {
     options = {
         ie: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2348,6 +2715,7 @@ issue_4962_2_strict_direct_inline: {
         ie: true,
         inline: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2731,6 +3099,7 @@ issue_5053_4: {
 issue_5082_1: {
     options = {
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2763,6 +3132,7 @@ issue_5082_1: {
 issue_5082_1_strict: {
     options = {
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2796,6 +3166,7 @@ issue_5082_2: {
     options = {
         inline: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2829,6 +3200,7 @@ issue_5082_2_static: {
     options = {
         inline: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -3330,3 +3702,331 @@ issue_5512: {
     expect_stdout: "PASS"
     node_version: ">=16"
 }
+
+issue_5531_1: {
+    options = {
+        inline: true,
+        toplevel: true,
+    }
+    input: {
+        class A {
+            p = function() {
+                var a = function f() {
+                    if (!a)
+                        console.log("foo");
+                    return 42;
+                }(a++);
+            }();
+        }
+        new A();
+        new A();
+    }
+    expect: {
+        class A {
+            p = function() {
+                var a = function f() {
+                    if (!a)
+                        console.log("foo");
+                    return 42;
+                }(a++);
+            }();
+        }
+        new A();
+        new A();
+    }
+    expect_stdout: [
+        "foo",
+        "foo",
+    ]
+    node_version: ">=12"
+}
+
+issue_5531_2: {
+    options = {
+        inline: true,
+        toplevel: true,
+    }
+    input: {
+        class A {
+            static p = function() {
+                var a = function f() {
+                    if (!a)
+                        console.log("foo");
+                    return 42;
+                }(a++);
+            }();
+        }
+        new A();
+        new A();
+    }
+    expect: {
+        class A {
+            static p = (a = function f() {
+                if (!a)
+                    console.log("foo");
+                return 42;
+            }(a++), void 0);
+        }
+        var a;
+        new A();
+        new A();
+    }
+    expect_stdout: "foo"
+    node_version: ">=12"
+}
+
+issue_5531_3: {
+    options = {
+        inline: true,
+    }
+    input: {
+        class A {
+            static {
+                (function() {
+                    var a = function f() {
+                        if (!a)
+                            console.log("foo");
+                        return 42;
+                    }(a++);
+                })();
+            }
+        }
+        new A();
+        new A();
+    }
+    expect: {
+        class A {
+            static {
+                a = function f() {
+                    if (!a)
+                        console.log("foo");
+                    return 42;
+                }(a++),
+                void 0;
+                var a;
+            }
+        }
+        new A();
+        new A();
+    }
+    expect_stdout: "foo"
+    node_version: ">=16"
+}
+
+issue_5662: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(new (function() {
+            var g = function(a) {
+                return a;
+            };
+            return class {
+                h(b) {
+                    return g(b);
+                }
+            };
+        }())().h("PASS"));
+    }
+    expect: {
+        console.log(new (function() {
+            var g = function(a) {
+                return a;
+            };
+            return class {
+                h(b) {
+                    return g(b);
+                }
+            };
+        }())().h("PASS"));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5682_class_key: {
+    mangle = {
+        properties: true,
+    }
+    input: {
+        "use strict";
+        function f(a) {
+            return "foo" in a;
+        }
+        class A {
+            foo() {}
+        }
+        console.log(f(new A()) ? "PASS" : "FAIL");
+    }
+    expect: {
+        "use strict";
+        function f(o) {
+            return "o" in o;
+        }
+        class A {
+            o() {}
+        }
+        console.log(f(new A()) ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5682_class_key_computed: {
+    mangle = {
+        properties: true,
+    }
+    input: {
+        "use strict";
+        function f(a) {
+            return "foo" in a;
+        }
+        class A {
+            ["foo"]() {}
+        }
+        console.log(f(new A()) ? "PASS" : "FAIL");
+    }
+    expect: {
+        "use strict";
+        function f(o) {
+            return "o" in o;
+        }
+        class A {
+            ["o"]() {}
+        }
+        console.log(f(new A()) ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5724: {
+    options = {
+        arrows: true,
+        inline: true,
+        keep_fargs: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        class A {
+            static P = function(a) {
+                console.log(a, a);
+            }(a);
+        }
+    }
+    expect: {
+        "use strict";
+        (function(a) {
+            console.log(a, a);
+        })(a);
+    }
+    expect_stdout: ReferenceError("a is not defined")
+    node_version: ">=12"
+}
+
+issue_5735_1: {
+    options = {
+        inline: true,
+    }
+    input: {
+        console.log(typeof function(a) {
+            return class {
+                static P = { ...a };
+            };
+        }([ 42..p ] = []));
+    }
+    expect: {
+        console.log(typeof function(a) {
+            return class {
+                static P = { ...a };
+            };
+        }([ 42..p ] = []));
+    }
+    expect_stdout: "function"
+    node_version: ">=12"
+}
+
+issue_5735_2: {
+    options = {
+        inline: true,
+    }
+    input: {
+        console.log(typeof function(a) {
+            return class {
+                p = a;
+            };
+        }(console.log("PASS")));
+    }
+    expect: {
+        console.log(typeof function(a) {
+            return class {
+                p = a;
+            };
+        }(console.log("PASS")));
+    }
+    expect_stdout: [
+        "PASS",
+        "function",
+    ]
+    node_version: ">=12"
+}
+
+issue_5747_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        "use strict";
+        (async function() {
+            var a = await 42;
+            class A {
+                static P = a && console.log(typeof this);
+            }
+        })();
+    }
+    expect: {
+        "use strict";
+        (async function() {
+            var a = await 42;
+            class A {
+                static P = a && console.log(typeof this);
+            }
+        })();
+    }
+    expect_stdout: "function"
+    node_version: ">=12"
+}
+
+issue_5747_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        "use strict";
+        (async function() {
+            var a = await 42;
+            class A {
+                static {
+                    a && console.log(typeof this);
+                }
+            }
+        })();
+    }
+    expect: {
+        "use strict";
+        (async function() {
+            var a = await 42;
+            class A {
+                static {
+                    a && console.log(typeof this);
+                }
+            }
+        })();
+    }
+    expect_stdout: "function"
+    node_version: ">=16"
+}

test/compress/collapse_vars.js

@@ -4996,7 +4996,7 @@ cascade_forin: {
     ]
 }
 
-unsafe_builtin: {
+unsafe_builtin_1: {
     options = {
         collapse_vars: true,
         pure_getters: "strict",
@@ -5020,6 +5020,46 @@ unsafe_builtin: {
     expect_stdout: "1 4"
 }
 
+unsafe_builtin_2: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        A = "PASS";
+        var a = A;
+        console.log(a);
+    }
+    expect: {
+        console.log(A = "PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+unsafe_builtin_3: {
+    options = {
+        collapse_vars: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        A = "PASS";
+        (function() {
+            var a = A;
+            console.log(a);
+        })();
+    }
+    expect: {
+        A = "PASS";
+        (function() {
+            console.log(A);
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
 return_1: {
     options = {
         collapse_vars: true,
@@ -7350,30 +7390,39 @@ substitution_assign: {
             b = 1 + (b = a);
             console.log(a, b);
         }
+        function f4(a, b) {
+            b = 1 + (a = b);
+            console.log(a, b);
+        }
         f1(42, "foo");
         f2(42, "foo");
         f3(42, "foo");
+        f4("bar", 41);
     }
     expect: {
         function f1(a, b) {
             console.log(f1 = a, a);
         }
         function f2(a, b) {
-            a = 1 + (b = a);
-            console.log(a, b);
+            console.log(a = 1 + (b = a), b);
         }
         function f3(a, b) {
-            b = 1 + (b = a);
+            console.log(a, b = 1 + (b = a));
+        }
+        function f4(a, b) {
+            b = 1 + (a = b);
             console.log(a, b);
         }
         f1(42, "foo");
         f2(42, "foo");
         f3(42, "foo");
+        f4("bar", 41);
     }
     expect_stdout: [
         "42 42",
         "43 42",
         "42 43",
+        "41 42",
     ]
 }
 
@@ -9321,12 +9370,11 @@ issue_4874: {
         })(a = 42);
     }
     expect: {
-        var a;
         null;
         (function(b) {
-            for (var c in a && a[console.log("PASS")])
+            for (var c in 42, 42[console.log("PASS")])
                 console;
-        })(a = 42);
+        })();
     }
     expect_stdout: "PASS"
 }
@@ -9865,7 +9913,8 @@ issue_5276: {
     }
     expect: {
         var a = A = "PASS";
-        a.p = a.p + null - 42;
+        a.p += null;
+        a.p -= 42;
         console.log(a);
     }
     expect_stdout: "PASS"
@@ -9979,3 +10028,332 @@ issue_5396: {
     }
     expect_stdout: "PASS"
 }
+
+issue_5568: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        A = "FAIL";
+        var a = (A = "PASS", !1);
+        for (var b in a);
+        console.log(A);
+    }
+    expect: {
+        A = "FAIL";
+        for (var b in !(A = "PASS"));
+        console.log(A);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5638_1: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a;
+        console;
+        a = [ 42 ];
+        console || FAIL(a);
+        console.log(a++);
+    }
+    expect: {
+        var a;
+        console;
+        a = [ 42 ];
+        console || FAIL(a);
+        console.log(a++);
+    }
+    expect_stdout: "42"
+}
+
+issue_5638_2: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a;
+        console;
+        a = [ 6 ];
+        console || FAIL(a);
+        console.log(a *= 7);
+    }
+    expect: {
+        var a;
+        console;
+        a = [ 6 ];
+        console || FAIL(a);
+        console.log(a *= 7);
+    }
+    expect_stdout: "42"
+}
+
+issue_5638_3: {
+    options = {
+        collapse_vars: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var log = console.log;
+        var a = { foo: 42 }, b;
+        for (var k in a) {
+            b = a[k];
+            log(k || b, b++);
+        }
+    }
+    expect: {
+        var log = console.log;
+        var a = { foo: 42 }, b;
+        for (var k in a) {
+            b = a[k];
+            log(k || b, b++);
+        }
+    }
+    expect_stdout: "foo 42"
+}
+
+issue_5638_4: {
+    options = {
+        collapse_vars: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var log = console.log;
+        var a = { foo: 6 }, b;
+        for (var k in a) {
+            b = a[k];
+            log(k || b, b *= 7);
+        }
+    }
+    expect: {
+        var log = console.log;
+        var a = { foo: 6 }, b;
+        for (var k in a) {
+            b = a[k];
+            log(k || b, b *= 7);
+        }
+    }
+    expect_stdout: "foo 42"
+}
+
+issue_5643: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 3, b;
+        a *= 7;
+        b = !!this;
+        console || console.log(b);
+        console.log(a * ++b);
+    }
+    expect: {
+        var a = 3, b;
+        a *= 7;
+        b = !!this;
+        console || console.log(b);
+        console.log(a * ++b);
+    }
+    expect_stdout: "42"
+}
+
+issue_5719: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 42, b;
+        switch (b = a) {
+          case a:
+          case b:
+          case a++:
+        }
+        console.log(a === b++ ? "PASS" : "FAIL");
+    }
+    expect: {
+        var a = 42, b;
+        switch (b = a) {
+          case a:
+          case b:
+          case a++:
+        }
+        console.log(a === b++ ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5779: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = A = "foo";
+        a.p = 42;
+        if (a && !a.p)
+            console.log("PASS");
+    }
+    expect: {
+        var a = A = "foo";
+        a.p = 42;
+        if (a, !a.p)
+            console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_1666: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var x = 42;
+        {
+            x();
+            function x() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof x);
+    }
+    expect: {
+        var x = 42;
+        {
+            x();
+            function x() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof x);
+    }
+    expect_stdout: true
+}
+
+issue_1666_strict: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        "use strict";
+        var x = 42;
+        {
+            x();
+            function x() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof x);
+    }
+    expect: {
+        "use strict";
+        var x = 42;
+        {
+            x();
+            function x() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof x);
+    }
+    expect_stdout: true
+}
+
+issue_1666_undefined: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var undefined = 42;
+        {
+            undefined();
+            function undefined() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof undefined);
+    }
+    expect: {
+        var undefined = 42;
+        {
+            undefined();
+            function undefined() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof undefined);
+    }
+    expect_stdout: true
+}
+
+issue_1666_undefined_strict: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        "use strict";
+        var undefined = 42;
+        {
+            undefined();
+            function undefined() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof undefined);
+    }
+    expect: {
+        "use strict";
+        var undefined = 42;
+        {
+            undefined();
+            function undefined() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof undefined);
+    }
+    expect_stdout: true
+}
+
+issue_5869: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a, b, log = console.log;
+        log();
+        a.p = 0;
+        b = a;
+        log(b);
+    }
+    expect: {
+        var a, log = console.log;
+        log();
+        log(void (a.p = 0));
+    }
+    expect_stdout: TypeError("Cannot set properties of undefined")
+}

test/compress/comparisons.js

@@ -275,6 +275,7 @@ issue_2857_3: {
 issue_2857_4: {
     options = {
         comparisons: true,
+        conditionals: true,
     }
     input: {
         function f(a, p) {
@@ -305,6 +306,7 @@ issue_2857_4: {
 issue_2857_5: {
     options = {
         comparisons: true,
+        conditionals: true,
     }
     input: {
         function f(a, p) {
@@ -528,6 +530,7 @@ nullish_assign: {
 nullish_chain: {
     options = {
         comparisons: true,
+        conditionals: true,
     }
     input: {
         var a;

test/compress/concat-strings.js

@@ -12,7 +12,7 @@ concat_1: {
 
         var e = 1 + x() + 2 + "X" + 3 + "boo";
 
-        // be careful with concatentation with "\0" with octal-looking strings.
+        // be careful with concatenation with "\0" with octal-looking strings.
         var f = "\0" + 360 + "\0" + 8 + "\0";
     }
     expect: {
@@ -273,6 +273,23 @@ concat_9: {
     expect_stdout: true
 }
 
+concat_sequence: {
+    options = {
+        collapse_vars: true,
+        strings: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        console.log(12 + (a = null, "34" + a));
+    }
+    expect: {
+        console.log(12 + "34" + null);
+    }
+    expect_stdout: "1234null"
+}
+
 issue_3689: {
     options = {
         strings: true,

test/compress/const.js

@@ -142,6 +142,80 @@ if_dead_branch: {
     expect_stdout: "undefined"
 }
 
+retain_tail_1: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        function f(a) {
+            var b = "foo";
+            if (a) {
+                const b = "bar";
+                while (console.log("baz"));
+                console.log(b);
+            } else {
+                while (console.log("moo"));
+                console.log(b);
+            }
+        }
+        f();
+        f(42);
+    }
+    expect: {
+        function f(a) {
+            var b = "foo";
+            if (a) {
+                const b = "bar";
+                while (console.log("baz"));
+                console.log(b);
+            } else {
+                while (console.log("moo"));
+                console.log(b);
+            }
+        }
+        f();
+        f(42);
+    }
+    expect_stdout: true
+}
+
+retain_tail_2: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        function f(a) {
+            var b = "foo";
+            if (a) {
+                while (console.log("bar"));
+                console.log(b);
+            } else {
+                const b = "baz";
+                while (console.log("moo"));
+                console.log(b);
+            }
+        }
+        f();
+        f(42);
+    }
+    expect: {
+        function f(a) {
+            var b = "foo";
+            if (a) {
+                while (console.log("bar"));
+                console.log(b);
+            } else {
+                const b = "baz";
+                while (console.log("moo"));
+                console.log(b);
+            }
+        }
+        f();
+        f(42);
+    }
+    expect_stdout: true
+}
+
 merge_vars_1: {
     options = {
         merge_vars: true,
@@ -579,6 +653,37 @@ dead_block_after_return: {
     expect_stdout: true
 }
 
+if_return_3: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        var a = "PASS";
+        function f(b) {
+            if (console) {
+                const b = a;
+                return b;
+            } else
+                while (console.log("FAIL 1"));
+            return b;
+        }
+        console.log(f("FAIL 2"));
+    }
+    expect: {
+        var a = "PASS";
+        function f(b) {
+            if (console) {
+                const b = a;
+                return b;
+            } else
+                while (console.log("FAIL 1"));
+            return b;
+        }
+        console.log(f("FAIL 2"));
+    }
+    expect_stdout: true
+}
+
 do_if_continue_1: {
     options = {
         if_return: true,
@@ -1872,3 +1977,257 @@ issue_5476: {
     }
     expect_stdout: "undefined"
 }
+
+issue_5516: {
+    options = {
+        inline: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(typeof function() {
+            try {} catch (a) {
+                (function f() {
+                    a;
+                })();
+            }
+            {
+                const a = function() {};
+                return a;
+            }
+        }());
+    }
+    expect: {
+        console.log(typeof function() {
+            try {} catch (a) {
+                void a;
+            }
+            {
+                const a = function() {};
+                return a;
+            }
+        }());
+    }
+    expect_stdout: "function"
+}
+
+issue_5580_1: {
+    mangle = {}
+    input: {
+        "use strict";
+        console.log(function(a, b, c) {
+            try {
+                FAIL;
+            } catch (e) {
+                return function() {
+                    var d = e, i, j;
+                    {
+                        const e = j;
+                    }
+                    return a;
+                }();
+            } finally {
+                const e = 42;
+            }
+        }("PASS"));
+    }
+    expect: {
+        "use strict";
+        console.log(function(r, n, t) {
+            try {
+                FAIL;
+            } catch (o) {
+                return function() {
+                    var n = o, t, c;
+                    {
+                        const o = c;
+                    }
+                    return r;
+                }();
+            } finally {
+                const c = 42;
+            }
+        }("PASS"));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5580_2: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        (function() {
+            try {
+                throw "PASS";
+            } catch (e) {
+                return function() {
+                    console.log(e);
+                    {
+                        const e = "FAIL 1";
+                    }
+                }();
+            } finally {
+                const e = "FAIL 2";
+            }
+        })();
+    }
+    expect: {
+        "use strict";
+        (function() {
+            try {
+                throw "PASS";
+            } catch (e) {
+                console.log(e);
+                {
+                    const e = "FAIL 1";
+                }
+                return;
+            } finally {
+                var e = "FAIL 2";
+            }
+        })();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5591: {
+    options = {
+        dead_code: true,
+        if_return: true,
+    }
+    input: {
+        "use strict";
+        function f(a) {
+            switch (console.log("foo")) {
+              case console.log("bar"):
+                if (console.log("baz"))
+                    return;
+                else {
+                    const a = 42;
+                    return;
+                }
+                break;
+              case null:
+                FAIL;
+            }
+        }
+        f();
+    }
+    expect: {
+        "use strict";
+        function f(a) {
+            switch (console.log("foo")) {
+              case console.log("bar"):
+                if (console.log("baz"))
+                    return;
+                else {
+                    const a = 42;
+                    return;
+                }
+              case null:
+                FAIL;
+            }
+        }
+        f();
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+        "baz",
+    ]
+    node_version: ">=4"
+}
+
+issue_5656: {
+    options = {
+        collapse_vars: true,
+        merge_vars: true,
+    }
+    input: {
+        console.log(function(a) {
+            var b = a;
+            b++;
+            {
+                const a = b;
+            }
+        }());
+    }
+    expect: {
+        console.log(function(a) {
+            var b = a;
+            {
+                const a = ++b;
+            }
+        }());
+    }
+    expect_stdout: true
+}
+
+issue_5660: {
+    options = {
+        merge_vars: true,
+        side_effects: true,
+    }
+    input: {
+        function f() {
+            try {
+                a;
+                var b;
+                return b;
+            } catch (e) {
+                var a = "FAIL";
+                const b = null;
+                return a;
+            }
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            try {
+                var b;
+                return b;
+            } catch (e) {
+                var a = "FAIL";
+                const b = null;
+                return a;
+            }
+        }
+        console.log(f());
+    }
+    expect_stdout: true
+}
+
+issue_5787: {
+    options = {
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            const a = 42;
+            switch (a) {
+              case 42:
+                const a = "PASS";
+                return a;
+            }
+        }());
+    }
+    expect: {
+        console.log(function() {
+            const a = 42;
+            switch (a) {
+              case 42:
+                const a = "PASS";
+                return a;
+            }
+        }());
+    }
+    expect_stdout: true
+}

test/compress/dead-code.js

@@ -1485,8 +1485,6 @@ self_assignments_5: {
     }
     expect: {
         var i = 0, l = [ "FAIL", "PASS" ];
-        l[0];
-        l[0];
         l[0] = l[1];
         console.log(l[0], 2);
     }
@@ -1707,3 +1705,28 @@ issue_5506: {
         "bar",
     ]
 }
+
+issue_5641: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        dead_code: true,
+    }
+    input: {
+        function f(a) {
+            if (a || b) {
+                var b = "PASS", c = b && console.log(b);
+            } else
+                var d = a || b;
+        }
+        f(42);
+    }
+    expect: {
+        function f(a) {
+            var b, c, d;
+            (a || b) && (b = "PASS") && console.log(b);
+        }
+        f(42);
+    }
+    expect_stdout: "PASS"
+}

test/compress/default-values.js

@@ -180,6 +180,26 @@ collapse_arg_sequence: {
     node_version: ">=6"
 }
 
+collapse_in_arg: {
+    options = {
+        collapse_vars: true,
+        keep_fargs: false,
+        unused: true,
+    }
+    input: {
+        (function(a, b = a) {
+            b("PASS");
+        })(console.log);
+    }
+    expect: {
+        (function(a) {
+            a("PASS");
+        })(console.log);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
 collapse_value_1: {
     options = {
         collapse_vars: true,
@@ -541,7 +561,7 @@ inline_side_effects_2: {
     }
     expect: {
         var a = 42;
-        [ [].e = --a ] = [ console ];
+        [ [][0] = --a ] = [ console ];
         console.log(a);
     }
     expect_stdout: "42"
@@ -648,6 +668,8 @@ drop_fargs: {
 hoist_vars: {
     options = {
         hoist_vars: true,
+        join_vars: true,
+        unused: true,
     }
     input: {
         var a = "PASS";
@@ -655,8 +677,7 @@ hoist_vars: {
         console.log(a, b);
     }
     expect: {
-        var a = "PASS";
-        var [ b = 42 ] = [];
+        var a = "PASS", [ b = 42 ] = [];
         console.log(a, b);
     }
     expect_stdout: "PASS 42"
@@ -1170,6 +1191,49 @@ mangle_arrow_2_toplevel: {
     node_version: ">=6.9.3"
 }
 
+collapse_preceding_simple_arg: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = "foo";
+        console.log(function(b, c = "bar") {
+            return b + c;
+        }(a, a));
+    }
+    expect: {
+        var a = "foo";
+        console.log(function(b, c = "bar") {
+            return a + c;
+        }(0, a));
+    }
+    expect_stdout: "foofoo"
+    node_version: ">=6"
+}
+
+drop_preceding_simple_arg: {
+    options = {
+        collapse_vars: true,
+        keep_fargs: false,
+        unused: true,
+    }
+    input: {
+        var a = "foo";
+        console.log(function(b, c = "bar") {
+            return b + c;
+        }(a, a));
+    }
+    expect: {
+        var a = "foo";
+        console.log(function(c = "bar") {
+            return a + c;
+        }(a));
+    }
+    expect_stdout: "foofoo"
+    node_version: ">=6"
+}
+
 issue_4444: {
     options = {
         collapse_vars: true,
@@ -1558,7 +1622,7 @@ issue_4502_4: {
         (function(a, b = console.log("FAIL")) {})(..."" + console.log(42));
     }
     expect: {
-        [ , [].e = console.log("FAIL") ] = [ ..."" + console.log(42) ];
+        [ , [][0] = console.log("FAIL") ] = [ ..."" + console.log(42) ];
     }
     expect_stdout: "42"
     node_version: ">=6"
@@ -1655,7 +1719,7 @@ issue_4540: {
     node_version: ">=6"
 }
 
-issue_4548: {
+issue_4548_1: {
     options = {
         merge_vars: true,
         toplevel: true,
@@ -1681,6 +1745,32 @@ issue_4548: {
     node_version: ">=6"
 }
 
+issue_4548_2: {
+    options = {
+        merge_vars: true,
+        toplevel: true,
+    }
+    input: {
+        A = "foo";
+        var a = A;
+        var [ b = c = "bar" ] = [ console, console.log(a) ];
+        console.log(c);
+        var c;
+    }
+    expect: {
+        A = "foo";
+        var a = A;
+        var [ b = c = "bar" ] = [ console, console.log(a) ];
+        console.log(c);
+        var c;
+    }
+    expect_stdout: [
+        "foo",
+        "undefined",
+    ]
+    node_version: ">=6"
+}
+
 issue_4588_1_unused: {
     options = {
         unused: true,
@@ -2023,7 +2113,7 @@ issue_5246_1: {
     }
     expect_stdout: "PASS"
     expect_warnings: [
-        "INFO: Dropping unused default argument {}=42 [test/compress/default-values.js:1,29]",
+        "INFO: Dropping unused default argument {} [test/compress/default-values.js:1,29]",
     ]
     node_version: ">=6"
 }
@@ -2183,7 +2273,7 @@ issue_5340_2: {
     }
     expect: {
         var a;
-        [ [].e = 0 ] = [ ({ p: a } = true).q ];
+        [ [][0] = 0 ] = [ ({ p: a } = true).q ];
         console.log(a);
     }
     expect_stdout: "undefined"
@@ -2203,7 +2293,7 @@ issue_5340_3: {
     }
     expect: {
         var a;
-        (function() {})(a = true["p"]);
+        (function() {})(a = true.p);
         console.log(a);
     }
     expect_stdout: "undefined"
@@ -2415,7 +2505,7 @@ issue_5463: {
         var a, b, b;
         console.log("PASS") && (
             b = a = void 0,
-            b = [a = FAIL] = a && a
+            b = [a = FAIL] = a
         );
     }
     expect_stdout: "PASS"
@@ -2462,3 +2552,586 @@ issue_5485: {
     expect_stdout: "PASS"
     node_version: ">=6"
 }
+
+issue_5533_1_keep_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(b = 42) {
+                            b;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_1_drop_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: false,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(b = 42) {
+                            b;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_2_keep_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f([ b ] = []) {
+                            b;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;) {
+                    var [ [] = [] ] = [];
+                    throw "PASS";
+                }
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_2_drop_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: false,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f([ b ] = []) {
+                            b;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;) {
+                    var [ [ , ] = [] ] = [];
+                    throw "PASS";
+                }
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_3_keep_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(b = 42, c = null) {
+                            c;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_3_drop_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: false,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(b = 42, c = null) {
+                            c;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_4_keep_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(b = 42, [ c ] = []) {
+                            c;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;) {
+                    var [ [] = [] ] = [];
+                    throw "PASS";
+                }
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_4_drop_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: false,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(b = 42, [ c ] = []) {
+                            c;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;) {
+                    var [ [] = [] ] = [];
+                    throw "PASS";
+                }
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5536: {
+    options = {
+        inline: true,
+        keep_fargs: true,
+        unused: true,
+    }
+    input: {
+        (function*() {
+            (([], a = 42) => {})([]);
+            console.log(typeof a);
+        })().next();
+    }
+    expect: {
+        (function*() {
+            [ , [][0] = 0 ] = [ [] ],
+            void 0;
+            console.log(typeof a);
+        })().next();
+    }
+    expect_stdout: "undefined"
+    node_version: ">=6"
+}
+
+issue_5566_1: {
+    options = {
+        unused: true,
+    }
+    input: {
+        (function(a, f = function() {
+            return a;
+        }) {
+            var a = "foo";
+            console.log(a, f());
+        })("bar");
+    }
+    expect: {
+        (function(a, f = function() {
+            return a;
+        }) {
+            var a = "foo";
+            console.log(a, f());
+        })("bar");
+    }
+    expect_stdout: "foo bar"
+    node_version: ">=6"
+}
+
+issue_5566_2: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+    }
+    input: {
+        (function(a, f = function() {
+            return a;
+        }) {
+            function a() {}
+            console.log(typeof a, typeof f());
+        })(42);
+    }
+    expect: {
+        (function(a, f = function() {
+            return a;
+        }) {
+            function a() {}
+            console.log(typeof a, typeof f());
+        })(42);
+    }
+    expect_stdout: "function number"
+    node_version: ">=6"
+}
+
+issue_5566_3: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(a, f = function() {
+            return a;
+        }) {
+            function a() {}
+            console.log(typeof a, typeof f());
+        })(42);
+    }
+    expect: {
+        (function(a, f = function() {
+            return a;
+        }) {
+            function a() {}
+            console.log(typeof a, typeof f());
+        })(42);
+    }
+    expect_stdout: "function number"
+    node_version: ">=6"
+}
+
+issue_5566_4: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(a, b = function() {
+            return a;
+        }) {
+            var a = 0;
+            b()("PASS");
+        })(console.log);
+    }
+    expect: {
+        (function(a, b = function() {
+            return a;
+        }) {
+            var a = 0;
+            b()("PASS");
+        })(console.log);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5566_5: {
+    options = {
+        hoist_vars: true,
+    }
+    input: {
+        (function(a, f = function() {
+            return a;
+        }) {
+            var a = "foo";
+            var b;
+            console.log(a, f());
+        })("bar");
+    }
+    expect: {
+        (function(a, f = function() {
+            return a;
+        }) {
+            var a, b;
+            a = "foo";
+            console.log(a, f());
+        })("bar");
+    }
+    expect_stdout: "foo bar"
+    node_version: ">=6"
+}
+
+issue_5651: {
+    options = {
+        ie: true,
+        unused: true,
+    }
+    input: {
+        console.log(function arguments(a = "FAIL") {
+            try {} catch (arguments) {
+                var arguments;
+            }
+            return arguments[0];
+        }());
+    }
+    expect: {
+        console.log(function arguments(a = "FAIL") {
+            try {} catch (arguments) {
+                var arguments;
+            }
+            return arguments[0];
+        }());
+    }
+    expect_stdout: true
+    node_version: ">=6"
+}
+
+issue_5774: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        evaluate: true,
+        join_vars: true,
+        reduce_vars: true,
+        sequences: true,
+        unsafe: true,
+    }
+    input: {
+        (function() {
+            while (console.log("PASS")) {
+                if (console) {
+                    a = void 0;
+                    var b = void 0;
+                    var c = void 0;
+                    ([ a = 0 ] = [ b, b ]);
+                    var a;
+                }
+            }
+        })();
+    }
+    expect: {
+        (function() {
+            while (console.log("PASS")) {
+                var a, b, c, a;
+                console && (
+                    c = b = a = void 0,
+                    [ a = 0 ] = [ a, a ]
+                );
+            }
+        })();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5863: {
+    options = {
+        collapse_vars: true,
+        hoist_vars: true,
+    }
+    input: {
+        console.log(typeof function f(a = function() {
+            f = 42;
+            return f;
+        }()) {
+            var f;
+            var f;
+            return a;
+        }());
+    }
+    expect: {
+        console.log(typeof function f(a = function() {
+            f = 42;
+            return f;
+        }()) {
+            var f;
+            return a;
+        }());
+    }
+    expect_stdout: "function"
+    node_version: ">=6"
+}

test/compress/destructured.js

@@ -472,6 +472,93 @@ funarg_collapse_vars_3: {
     node_version: ">=6"
 }
 
+funarg_collapse_vars_4: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        (function(b, { log: c }) {
+            c(b);
+        })(a, console);
+    }
+    expect: {
+        var a = "PASS";
+        (function(b, { log: c }) {
+            c(a);
+        })(0, console);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+funarg_collapse_vars_5: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        A = "FAIL";
+        B = "PASS";
+        try {
+            console.log(function({}, a) {
+                return a;
+            }(null, A = B));
+        } catch (e) {}
+        console.log(A);
+    }
+    expect: {
+        A = "FAIL";
+        B = "PASS";
+        try {
+            console.log(function({}, a) {
+                return a;
+            }(null, A = B));
+        } catch (e) {}
+        console.log(A);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+funarg_collapse_vars_6: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        A = "FAIL";
+        B = "PASS";
+        function f() {
+            console.log(function({}, a) {
+                return a;
+            }(null, A = B));
+        }
+        try {
+            f();
+        } catch (e) {
+            console.log(A);
+        }
+    }
+    expect: {
+        A = "FAIL";
+        B = "PASS";
+        function f() {
+            console.log(function({}, a) {
+                return a;
+            }(null, A = B));
+        }
+        try {
+            f();
+        } catch (e) {
+            console.log(A);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
 funarg_reduce_vars_1: {
     options = {
         reduce_vars: true,
@@ -1219,7 +1306,7 @@ keep_reference: {
     }
     expect: {
         var a = [ {}, 42 ];
-        var [ b ] = a;
+        var b = a[0];
         console.log(a[0] === b ? "PASS" : "FAIL");
     }
     expect_stdout: "PASS"
@@ -1252,7 +1339,7 @@ maintain_position_var: {
     }
     expect: {
         A = "FAIL";
-        var [ , b ] = [ A ];
+        var b = [ A ][1];
         console.log(b || "PASS");
     }
     expect_stdout: "PASS"
@@ -1295,7 +1382,7 @@ side_effects_object: {
         }
     }
     expect: {
-        var a = null, c = (console, 42["c"]);
+        var a = null, c = (console, 42..c);
         try {
             c[a = "PASS"];
         } catch (e) {
@@ -1565,6 +1652,8 @@ fn_name_unused: {
 hoist_vars: {
     options = {
         hoist_vars: true,
+        join_vars: true,
+        unused: true,
     }
     input: {
         var a = "PASS";
@@ -1572,8 +1661,7 @@ hoist_vars: {
         console.log(a, b);
     }
     expect: {
-        var a = "PASS";
-        var [ b ] = [ 42 ];
+        var a = "PASS", b = [ 42 ][0];
         console.log(a, b);
     }
     expect_stdout: "PASS 42"
@@ -1596,7 +1684,7 @@ singleton_1: {
     expect: {
         var b, a = "P"[0], o = {};
         o.p = [ "FAIL"["1"] ][0];
-        o.q = { foo: "S"[0] }["foo"];
+        o.q = { foo: "S"[0] }.foo;
         [ b = "S" ] = [];
         console.log(a + o.p + o.q + b);
     }
@@ -1649,6 +1737,23 @@ singleton_side_effects: {
     node_version: ">=6"
 }
 
+mangle_properties: {
+    mangle = {
+        properties: {
+            domprops: true,
+        },
+    }
+    input: {
+        function f({ p: a }) {
+            return a;
+        }
+        console.log(f({ p: "PASS" }));
+    }
+    expect_exact: 'function f({n}){return n}console.log(f({n:"PASS"}));'
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
 issue_4280: {
     options = {
         evaluate: true,
@@ -1815,8 +1920,8 @@ issue_4288: {
                 console.log(typeof b);
             }()]: a,
         }) {
-            var b = a;
-            b++;
+            var a = a;
+            a++;
         }
         f(0);
     }
@@ -1989,17 +2094,16 @@ issue_4312: {
         console.log(a);
     }
     expect: {
-        var a;
         b = "PASS",
         c = "FAIL",
         [
             {
-                [a = b]: d,
+                [c = b]: d,
             },
         ] = [ c && c ],
         void 0;
         var b, c, d;
-        console.log(a);
+        console.log(c);
     }
     expect_stdout: "PASS"
     node_version: ">=6"
@@ -3497,7 +3601,7 @@ issue_5314_2: {
         A = this;
         new function() {
             [ {
-                [console.log(this === A ? "FAIL" : "PASS")]: [].e,
+                [console.log(this === A ? "FAIL" : "PASS")]: [][0],
             } ] = [ 42 ];
         }();
     }
@@ -3646,3 +3750,494 @@ issue_5485: {
     expect_stdout: "PASS"
     node_version: ">=6"
 }
+
+issue_5533_keep_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f([ b ]) {
+                            b;
+                            throw "PASS";
+                        })([]);
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_drop_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: false,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f([ b ]) {
+                            b;
+                            throw "PASS";
+                        })([]);
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5573: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var log = console.log;
+        var a = "FAIL";
+        (function([ { [log(a)]: b } ]) {
+            A = 42;
+        })((a = "PASS", [ {} ]));
+        log(a, A);
+    }
+    expect: {
+        var log = console.log;
+        var a = "FAIL";
+        (function([ { [log(a)]: b } ]) {
+            A = 42;
+        })((a = "PASS", [ {} ]));
+        log(a, A);
+    }
+    expect_stdout: [
+        "PASS",
+        "PASS 42",
+    ]
+    node_version: ">=6"
+}
+
+issue_5651: {
+    options = {
+        ie: true,
+        unused: true,
+    }
+    input: {
+        console.log(function arguments({}) {
+            try {} catch (arguments) {
+                var arguments;
+            }
+            return arguments[0];
+        }("PASS"));
+    }
+    expect: {
+        console.log(function arguments({}) {
+            try {} catch (arguments) {
+                var arguments;
+            }
+            return arguments[0];
+        }("PASS"));
+    }
+    expect_stdout: true
+    node_version: ">=6"
+}
+
+issue_5843_1: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var { p: a } = {
+            __proto__: {
+                p: "PASS",
+            },
+        };
+        console.log(a);
+    }
+    expect: {
+        var a = {
+            __proto__: {
+                p: "PASS",
+            },
+        }.p;
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5843_2: {
+    options = {
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        ({ p: a } = {
+            __proto__: {
+                p: "PASS",
+            },
+        });
+        console.log(a);
+    }
+    expect: {
+        var a;
+        a = {
+            __proto__: {
+                p: "PASS",
+            },
+        }.p;
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5844: {
+    options = {
+        inline: true,
+    }
+    input: {
+        try {
+            (function(a) {
+                [ a.p ] = 42;
+            })(console.log("PASS"));
+        } catch (e) {}
+    }
+    expect: {
+        try {
+            (function(a) {
+                [ a.p ] = 42;
+            })(console.log("PASS"));
+        } catch (e) {}
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5854_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        console.log(function(a) {
+            var b = a;
+            a++;
+            [ b[0] ] = [ "foo" ];
+            return a;
+        }([]) ? "PASS" : "FAIL");
+    }
+    expect: {
+        console.log(function(a) {
+            var b = a;
+            a++;
+            [ b[0] ] = [ "foo" ];
+            return a;
+        }([]) ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5854_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        console.log(function(a) {
+            var b = a;
+            a++;
+            ({ p: b[0] } = { p: "foo" });
+            return a;
+        }([]) ? "PASS" : "FAIL");
+    }
+    expect: {
+        console.log(function(a) {
+            var b = a;
+            a++;
+            ({ p: b[0] } = { p: "foo" });
+            return a;
+        }([]) ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_1: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = {};
+        var { p: { q: b } } = {
+            p: a,
+            r: a.q = "PASS",
+        };
+        console.log(b);
+    }
+    expect: {
+        var a = {};
+        var { q: b } = {
+            p: a,
+            r: a.q = "PASS",
+        }.p;
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_2: {
+    options = {
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = {}, b;
+        ({ p: { q: b } } = {
+            p: a,
+            r: a.q = "PASS",
+        });
+        console.log(b);
+    }
+    expect: {
+        var b, a = {};
+        ({ q: b } = {
+            p: a,
+            r: a.q = "PASS",
+        }.p);
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_3: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = {};
+        var [ { p: b } ] = [ a, a.p = "PASS" ];
+        console.log(b);
+    }
+    expect: {
+        var a = {};
+        var { p: b } = [ a, a.p = "PASS" ][0];
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_4: {
+    options = {
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = {}, b;
+        [ { p: b } ] = [ a, a.p = "PASS" ];
+        console.log(b);
+    }
+    expect: {
+        var b, a = {};
+        ({ p: b } = [ a, a.p = "PASS" ][0]);
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_5: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = [];
+        var [ [ b ] ] = [ a, a[0] = "PASS" ];
+        console.log(b);
+    }
+    expect: {
+        var a = [];
+        var [ b ] = [ a, a[0] = "PASS" ][0];
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_6: {
+    options = {
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = [], b;
+        [ [ b ] ] = [ a, a[0] = "PASS" ];
+        console.log(b);
+    }
+    expect: {
+        var b, a = [];
+        [ b ] = [ a, a[0] = "PASS" ][0];
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_7: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = {};
+        var [ { p: b }, c ] = [ a, a.p = {} ];
+        console.log(b === c ? "PASS" : "FAIL");
+    }
+    expect: {
+        var a = {};
+        var [ { p: b }, c ] = [ a, a.p = {} ];
+        console.log(b === c ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_8: {
+    options = {
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = {}, b, c;
+        [ { p: b }, c ] = [ a, a.p = {} ];
+        console.log(b === c ? "PASS" : "FAIL");
+    }
+    expect: {
+        var b, c, a = {};
+        [ { p: b }, c ] = [ a, a.p = {} ];
+        console.log(b === c ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_9: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = {};
+        var [ b, { p: c } ] = [ a.p = {}, a ];
+        console.log(b === c ? "PASS" : "FAIL");
+    }
+    expect: {
+        var a = {};
+        var [ b, c ] = [ a.p = {}, a.p ];
+        console.log(b === c ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_10: {
+    options = {
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = {}, b, c;
+        [ b, { p: c } ] = [ a.p = {}, a ];
+        console.log(b === c ? "PASS" : "FAIL");
+    }
+    expect: {
+        var b, c, a = {};
+        [ b, c ] = [ a.p = {}, a.p ];
+        console.log(b === c ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_11: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a = {};
+        var { p: { q: b } } = { p: a = { q: {} } };
+        console.log(a.q === b ? "PASS" : "FAIL");
+    }
+    expect: {
+        var a = {};
+        var b = { p: (a = { q: {} }).q }.p;
+        console.log(a.q === b ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5866_12: {
+    options = {
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = {}, b;
+        ({ p: { q: b } } = { p: a = { q: {} } });
+        console.log(a.q === b ? "PASS" : "FAIL");
+    }
+    expect: {
+        var b, a = {};
+        b = { p: (a = { q: {} }).q }.p;
+        console.log(a.q === b ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}

test/compress/directives.js

@@ -131,19 +131,34 @@ valid_after_invalid_2: {
 }
 
 issue_5368_1: {
+    expression = true
     options = {
         directives: true,
         expression: true,
     }
     input: {
-        "foo";
-    }
-    expect: {
-        "foo";
+        "foo"
     }
+    expect_exact: '"foo"'
+    expect_stdout: "foo"
 }
 
 issue_5368_2: {
+    expression = true
+    options = {
+        directives: true,
+        expression: true,
+    }
+    input: {
+        (function() {
+            "foo";
+        })()
+    }
+    expect_exact: "function(){}()"
+    expect_stdout: "undefined"
+}
+
+issue_5368_3: {
     options = {
         directives: true,
         expression: true,

test/compress/drop-unused.js

@@ -409,6 +409,15 @@ drop_toplevel_retain: {
         a = 2;
         console.log(3);
     }
+    expect_stdout: "3"
+    expect_warnings: [
+        "INFO: Retaining variable a",
+        "INFO: Retaining variable f",
+        "INFO: Dropping unused variable b [test/compress/drop-unused.js:1,15]",
+        "INFO: Dropping unused variable c [test/compress/drop-unused.js:1,22]",
+        "INFO: Dropping unused function g [test/compress/drop-unused.js:8,17]",
+        "WARN: Dropping unused function h [test/compress/drop-unused.js:9,17]",
+    ]
 }
 
 drop_toplevel_retain_array: {
@@ -442,6 +451,15 @@ drop_toplevel_retain_array: {
         a = 2;
         console.log(3);
     }
+    expect_stdout: "3"
+    expect_warnings: [
+        "INFO: Retaining variable a",
+        "INFO: Retaining variable f",
+        "INFO: Dropping unused variable b [test/compress/drop-unused.js:1,15]",
+        "INFO: Dropping unused variable c [test/compress/drop-unused.js:1,22]",
+        "INFO: Dropping unused function g [test/compress/drop-unused.js:8,17]",
+        "WARN: Dropping unused function h [test/compress/drop-unused.js:9,17]",
+    ]
 }
 
 drop_toplevel_retain_regex: {
@@ -471,6 +489,15 @@ drop_toplevel_retain_regex: {
         a = 2;
         console.log(3);
     }
+    expect_stdout: "3"
+    expect_warnings: [
+        "INFO: Retaining variable a",
+        "INFO: Retaining variable f",
+        "INFO: Dropping unused variable b [test/compress/drop-unused.js:1,15]",
+        "INFO: Dropping unused variable c [test/compress/drop-unused.js:1,22]",
+        "INFO: Dropping unused function g [test/compress/drop-unused.js:8,17]",
+        "WARN: Dropping unused function h [test/compress/drop-unused.js:9,17]",
+    ]
 }
 
 drop_toplevel_all_retain: {
@@ -501,6 +528,15 @@ drop_toplevel_all_retain: {
         a = 2;
         console.log(3);
     }
+    expect_stdout: "3"
+    expect_warnings: [
+        "INFO: Retaining variable a",
+        "INFO: Retaining variable f",
+        "INFO: Dropping unused variable b [test/compress/drop-unused.js:1,15]",
+        "INFO: Dropping unused variable c [test/compress/drop-unused.js:1,22]",
+        "INFO: Dropping unused function g [test/compress/drop-unused.js:8,17]",
+        "WARN: Dropping unused function h [test/compress/drop-unused.js:9,17]",
+    ]
 }
 
 drop_toplevel_funcs_retain: {
@@ -532,6 +568,12 @@ drop_toplevel_funcs_retain: {
         function g() {}
         console.log(b = 3);
     }
+    expect_stdout: "3"
+    expect_warnings: [
+        "INFO: Retaining variable a",
+        "INFO: Retaining variable f",
+        "WARN: Dropping unused function h [test/compress/drop-unused.js:9,17]",
+    ]
 }
 
 drop_toplevel_vars_retain: {
@@ -564,6 +606,13 @@ drop_toplevel_vars_retain: {
         function h() {}
         console.log(3);
     }
+    expect_stdout: "3"
+    expect_warnings: [
+        "INFO: Retaining variable a",
+        "INFO: Retaining variable f",
+        "INFO: Dropping unused variable b [test/compress/drop-unused.js:1,15]",
+        "INFO: Dropping unused variable c [test/compress/drop-unused.js:1,22]",
+    ]
 }
 
 drop_toplevel_keep_assign: {
@@ -1829,7 +1878,7 @@ issue_2846: {
         var c = function(a, b) {
             a = 0;
             b && b(a);
-            return a++;
+            return +a;
         }();
         console.log(c);
     }
@@ -2927,14 +2976,12 @@ issue_4025: {
         console.log(a, b, d);
     }
     expect: {
-        var c = 0;
         try {
-            console.log(c);
+            console.log(0);
         } finally {
-            var d = c + 1;
-            c = 0;
+            0;
         }
-        console.log(1, 1, d);
+        console.log(1, 1, 1);
     }
     expect_stdout: [
         "0",
@@ -3647,7 +3694,7 @@ issue_5224: {
                 (function() {
                     var a = "FAIL 1";
                     null;
-                    a = console.log(a);
+                    console.log(a);
                 })(function() {
                     console.log(1 / 0);
                     a;
@@ -3685,3 +3732,85 @@ issue_5271: {
     }
     expect_stdout: "42"
 }
+
+issue_5533_keep_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(b) {
+                            b;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5533_drop_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: false,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(b) {
+                            b;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+}

test/compress/evaluate.js

@@ -3390,3 +3390,29 @@ issue_5380: {
     }
     expect_stdout: "PASS"
 }
+
+issue_5558: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        reduce_vars: true,
+        sequences: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 99, b = 0;
+        a++;
+        b++;
+        b += a;
+        b *= a;
+        b += a;
+        console.log(a);
+    }
+    expect: {
+        var a = 99, b = 0;
+        b++,
+        b = (b += ++a) * a + a,
+        console.log(a);
+    }
+    expect_stdout: "100"
+}

test/compress/exports.js

@@ -109,6 +109,17 @@ foreign: {
     expect_exact: 'export*from"foo";export{}from"bar";export*as a from"baz";export{default}from"moo";export{b,c as case,default as delete,d}from"moz";'
 }
 
+non_identifiers: {
+    beautify = {
+        quote_style: 3,
+    }
+    input: {
+        export * as "42" from 'foo';
+        export { '42', "delete" as 'foo' } from "bar";
+    }
+    expect_exact: "export*as\"42\"from'foo';export{'42',delete as foo}from\"bar\";"
+}
+
 same_quotes: {
     beautify = {
         beautify: true,
@@ -249,7 +260,7 @@ hoist_exports_2: {
         }
     }
     expect: {
-        let e, a = 42["foo"];
+        let e, a = 42..foo;
         function f(t, { [e]: o }) {
             t(o, f);
         }
@@ -549,3 +560,23 @@ issue_5444: {
         export var a = console;
     }
 }
+
+issue_5628: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a;
+        export default function f() {
+            for (a in 42);
+        }
+        console.log(a);
+    }
+    expect: {
+        var a;
+        export default function f() {
+            for (a in 42);
+        }
+        console.log(a);
+    }
+}

test/compress/functions.js

@@ -629,7 +629,7 @@ inline_binary_and: {
                 return void "moo";
                 return;
             } else
-                return;
+                return void 0;
         }());
     }
     expect_stdout: [
@@ -5512,6 +5512,40 @@ substitute_use_strict: {
     ]
 }
 
+substitute_assignment: {
+    options = {
+        evaluate: true,
+        inline: true,
+        passes: 2,
+        properties: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f(a, b, c) {
+            a[b] = c;
+        }
+        var o = {};
+        f(o, 42, null);
+        f(o, "foo", "bar");
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {};
+        o[42] = null;
+        o.foo = "bar";
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: [
+        "42 null",
+        "foo bar",
+    ]
+}
+
 issue_3833_1: {
     options = {
         inline: 3,
@@ -5582,7 +5616,7 @@ issue_3835: {
             return f();
         })();
     }
-    expect_stdout: true
+    expect_stdout: RangeError("Maximum call stack size exceeded")
 }
 
 issue_3836_1: {
@@ -7835,7 +7869,7 @@ issue_5249_1: {
                 while (console.log("FAIL 2"));
                 return;
             } else
-                return;
+                return void 0;
             throw "FAIL 3";
         }());
     }
@@ -8629,6 +8663,7 @@ module_inline: {
         inline: true,
         module: true,
         reduce_vars: true,
+        toplevel: true,
     }
     input: {
         var a = f;
@@ -8646,3 +8681,293 @@ module_inline: {
     }
     expect_stdout: "true"
 }
+
+single_use_inline_collision: {
+    options = {
+        inline: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        (function() {
+            var f = function() {
+                while (console.log(a));
+            };
+            (function() {
+                (function() {
+                    f();
+                })();
+                (function(a) {
+                    a || a("FAIL");
+                })(console.log);
+            })();
+        })();
+    }
+    expect: {
+        var a = "PASS";
+        (function() {
+            (function() {
+                while (console.log(a));
+                return;
+            })();
+            (function(a) {
+                a || a("FAIL");
+            })(console.log);
+            return;
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5692: {
+    options = {
+        inline: true,
+    }
+    input: {
+        (function() {
+            while (console.log("PASS"))
+                if (console)
+                    return;
+        })();
+    }
+    expect: {
+        (function() {
+            while (console.log("PASS"))
+                if (console)
+                    return;
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5766_1: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        functions: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        log = function(a) {
+            console.log(typeof a);
+        };
+        do {
+            (function() {
+                try {
+                    var f = function() {};
+                    log(f && f);
+                } catch (e) {}
+            })();
+        } while (0);
+    }
+    expect: {
+        log = function(a) {
+            console.log(typeof a);
+        };
+        do {
+            try {
+                function f() {}
+                log(f);
+            } catch (e) {}
+        } while (0);
+    }
+    expect_stdout: "function"
+}
+
+issue_5766_2: {
+    options = {
+        evaluate: true,
+        functions: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        log = function(a) {
+            console.log(typeof a);
+        };
+        do {
+            (function() {
+                try {
+                    var f = function() {};
+                    log(f && f);
+                } catch (e) {}
+            })();
+        } while (0);
+    }
+    expect: {
+        log = function(a) {
+            console.log(typeof a);
+        };
+        do {
+            try {
+                function f() {}
+                log(f);
+            } catch (e) {}
+        } while (0);
+    }
+    expect_stdout: "function"
+}
+
+issue_5841_1: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        passes: 2,
+        reduce_funcs: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = 42;
+        (function() {
+            f();
+            var b = f();
+            function f() {
+                if (console && a)
+                    g && g();
+            }
+            function g() {
+                var c;
+                for (;console.log("foo"););
+                (function h(d) {
+                    d && d.p;
+                })();
+            }
+        })();
+    }
+    expect: {
+        var a = 42;
+        (function() {
+            f();
+            f();
+            function f() {
+                {
+                    if (console && a) {
+                        for (;console.log("foo"););
+                        return;
+                    }
+                    return;
+                }
+            }
+        })();
+    }
+    expect_stdout: [
+        "foo",
+        "foo",
+    ]
+}
+
+issue_5841_2: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        if_return: true,
+        inline: true,
+        join_vars: true,
+        passes: 2,
+        reduce_funcs: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = 42;
+        (function() {
+            f();
+            var b = f();
+            function f() {
+                if (console && a)
+                    g && g();
+            }
+            function g() {
+                var c;
+                for (;console.log("foo"););
+                (function h(d) {
+                    d && d.p;
+                })();
+            }
+        })();
+    }
+    expect: {
+        var a = 42;
+        (function() {
+            f();
+            f();
+            function f() {
+                if (console && a)
+                    for (;console.log("foo"););
+            }
+        })();
+    }
+    expect_stdout: [
+        "foo",
+        "foo",
+    ]
+}
+
+issue_5851_1: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        console.log("PASS") && f();
+        function f() {
+            return f();
+        }
+        f;
+    }
+    expect: {
+        console.log("PASS") && f();
+        function f() {
+            return f();
+        }
+        f;
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5851_2: {
+    options = {
+        conditionals: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = f();
+        f();
+        function f() {
+            if (console.log("foo"))
+                console && f();
+        }
+    }
+    expect: {
+        f();
+        f();
+        function f() {
+            console.log("foo") && console && f();
+        }
+    }
+    expect_stdout: [
+        "foo",
+        "foo",
+    ]
+}

test/compress/hoist_props.js

@@ -462,6 +462,11 @@ issue_2473_1: {
         var x = {};
         var y = [];
     }
+    expect_warnings: [
+        "INFO: Retaining variable x",
+        "INFO: Retaining variable y",
+        "WARN: Dropping unused variable z [test/compress/hoist_props.js:3,12]",
+    ]
 }
 
 issue_2473_2: {
@@ -484,6 +489,11 @@ issue_2473_2: {
         var x = {};
         var y = [];
     }
+    expect_warnings: [
+        "INFO: Retaining variable x",
+        "INFO: Retaining variable y",
+        "WARN: Dropping unused variable z [test/compress/hoist_props.js:3,12]",
+    ]
 }
 
 issue_2473_3: {
@@ -509,6 +519,9 @@ issue_2473_3: {
         console.log(o.a, o.b);
     }
     expect_stdout: "1 2"
+    expect_warnings: [
+        "INFO: Retaining variable o",
+    ]
 }
 
 issue_2473_4: {
@@ -535,6 +548,9 @@ issue_2473_4: {
         })();
     }
     expect_stdout: "1 2"
+    expect_warnings: [
+        "INFO: Dropping unused variable o [test/compress/hoist_props.js:2,16]",
+    ]
 }
 
 issue_2508_1: {

test/compress/hoist_vars.js

@@ -2,6 +2,8 @@ statements: {
     options = {
         hoist_funs: false,
         hoist_vars: true,
+        join_vars: true,
+        unused: true,
     }
     input: {
         function f() {
@@ -25,6 +27,8 @@ statements_funs: {
     options = {
         hoist_funs: true,
         hoist_vars: true,
+        join_vars: true,
+        unused: true,
     }
     input: {
         function f() {
@@ -48,6 +52,8 @@ sequences: {
     options = {
         hoist_funs: false,
         hoist_vars: true,
+        join_vars: true,
+        unused: true,
     }
     input: {
         function f() {
@@ -71,6 +77,8 @@ sequences_funs: {
     options = {
         hoist_funs: true,
         hoist_vars: true,
+        join_vars: true,
+        unused: true,
     }
     input: {
         function f() {
@@ -108,7 +116,8 @@ catch_var: {
         console.log(a);
     }
     expect: {
-        var a = "PASS";
+        a = "PASS";
+        var a;
         console.log(a);
     }
     expect_stdout: "PASS"
@@ -118,6 +127,8 @@ issue_2295: {
     options = {
         collapse_vars: true,
         hoist_vars: true,
+        join_vars: true,
+        unused: true,
     }
     input: {
         function foo(o) {
@@ -139,6 +150,7 @@ issue_4487_1: {
     options = {
         functions: true,
         hoist_vars: true,
+        join_vars: true,
         keep_fnames: true,
         reduce_vars: true,
         toplevel: true,
@@ -163,6 +175,7 @@ issue_4487_2: {
     options = {
         functions: true,
         hoist_vars: true,
+        join_vars: true,
         keep_fnames: true,
         passes: 2,
         reduce_vars: true,
@@ -188,6 +201,7 @@ issue_4487_3: {
     options = {
         functions: true,
         hoist_vars: true,
+        join_vars: true,
         keep_fnames: true,
         passes: 3,
         reduce_vars: true,
@@ -214,6 +228,7 @@ issue_4489: {
         evaluate: true,
         hoist_vars: true,
         reduce_vars: true,
+        sequences: true,
         toplevel: true,
         unused: true,
     }
@@ -248,8 +263,7 @@ issue_4517: {
     }
     expect: {
         console.log(function() {
-            var a = 2;
-            return (A = a) + typeof !1;
+            return (A = 2) + typeof !1;
         }());
     }
     expect_stdout: "2boolean"
@@ -260,6 +274,7 @@ issue_4736: {
         collapse_vars: true,
         evaluate: true,
         hoist_vars: true,
+        join_vars: true,
         merge_vars: true,
         reduce_vars: true,
         toplevel: true,
@@ -279,7 +294,7 @@ issue_4736: {
     expect: {
         (function() {
             (function() {
-                0,
+                0;
                 console.log(1 << 30);
             })();
         })();
@@ -291,6 +306,7 @@ issue_4839: {
     options = {
         evaluate: true,
         hoist_vars: true,
+        join_vars: true,
         keep_fargs: false,
         reduce_vars: true,
         toplevel: true,
@@ -317,6 +333,7 @@ issue_4859: {
     options = {
         evaluate: true,
         hoist_vars: true,
+        join_vars: true,
         keep_infinity: true,
         merge_vars: true,
         reduce_vars: true,
@@ -347,6 +364,7 @@ issue_4893_1: {
         evaluate: true,
         hoist_vars: true,
         reduce_vars: true,
+        side_effects: true,
         toplevel: true,
         unused: true,
     }
@@ -367,9 +385,8 @@ issue_4893_1: {
     }
     expect: {
         try{
-            (function f() {
+            (function() {
                 null.p += 42;
-                f;
             })();
         } catch (e) {
             console.log("PASS");
@@ -406,9 +423,7 @@ issue_4893_2: {
     expect: {
         try{
             (function() {
-                var a;
-                a = null;
-                a.p += 42;
+                null.p += 42;
             })();
         } catch (e) {
             console.log("PASS");
@@ -441,7 +456,7 @@ issue_4898: {
     expect_stdout: "PASS"
 }
 
-issue_5187: {
+issue_5187_1: {
     options = {
         hoist_props: true,
         hoist_vars: true,
@@ -459,6 +474,37 @@ issue_5187: {
         }
         f();
     }
+    expect: {
+        (function() {
+            var a, b;
+            a = 42;
+            do {
+                b = { 0: a++ };
+            } while (console.log(b[b ^= 0]));
+        })();
+    }
+    expect_stdout: "42"
+}
+
+issue_5187_2: {
+    options = {
+        hoist_props: true,
+        hoist_vars: true,
+        join_vars: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            var a = 42;
+            do {
+                var b = { 0: a++ };
+            } while (console.log(b[b ^= 0]));
+        }
+        f();
+    }
     expect: {
         (function() {
             var b, a = 42;
@@ -547,9 +593,9 @@ issue_5411_1: {
         console.log(b);
     }
     expect: {
-        var b, c, a = "PASS";
+        var a, b, c;
         b++;
-        b = a;
+        b = a = "PASS";
         c = c && c[b];
         console.log(b);
     }
@@ -563,6 +609,7 @@ issue_5411_2: {
         evaluate: true,
         hoist_vars: true,
         reduce_vars: true,
+        sequences: true,
         toplevel: true,
         unused: true,
     }
@@ -575,9 +622,9 @@ issue_5411_2: {
     }
     expect: {
         var b, c;
-        b++;
+        b++,
         b = "PASS",
-        c = c && c[b];
+        c,
         console.log(b);
     }
     expect_stdout: "PASS"
@@ -596,6 +643,30 @@ issue_5411_3: {
         var a = A = a;
         console.log(A);
     }
+    expect: {
+        var a;
+        a = console;
+        a = A = ++a;
+        console.log(A);
+    }
+    expect_stdout: "NaN"
+}
+
+issue_5411_4: {
+    options = {
+        collapse_vars: true,
+        hoist_vars: true,
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = console;
+        a++;
+        var a = A = a;
+        console.log(A);
+    }
     expect: {
         var a = console;
         a = A = ++a;
@@ -603,3 +674,130 @@ issue_5411_3: {
     }
     expect_stdout: "NaN"
 }
+
+issue_5626: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        hoist_vars: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = function() {
+            return console.log(arguments[0]), 42;
+        }("PASS") ? null : "foo";
+        for (var b in a)
+            FAIL;
+    }
+    expect: {
+        (function() {
+            console.log(arguments[0]);
+        }("PASS"));
+        for (var b in null)
+            FAIL;
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5638_1: {
+    options = {
+        collapse_vars: true,
+        hoist_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "FAIL";
+        var a = [ 42 ];
+        console || FAIL(a);
+        console.log(a++);
+    }
+    expect: {
+        var a;
+        a = "FAIL";
+        a = [ 42 ];
+        console || FAIL(a);
+        console.log(a++);
+    }
+    expect_stdout: "42"
+}
+
+issue_5638_2: {
+    options = {
+        collapse_vars: true,
+        hoist_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "FAIL";
+        var a = [ 6 ];
+        console || FAIL(a);
+        console.log(a *= 7);
+    }
+    expect: {
+        var a;
+        a = "FAIL";
+        a = [ 6 ];
+        console || FAIL(a);
+        console.log(a *= 7);
+    }
+    expect_stdout: "42"
+}
+
+issue_5638_3: {
+    options = {
+        collapse_vars: true,
+        hoist_vars: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var log = console.log;
+        var o = { foo: 42 };
+        for (var k in o) {
+            var v = o[k];
+            log(k || v, v++);
+        }
+    }
+    expect: {
+        var log, o, k, v;
+        log = console.log;
+        for (k in o = { foo: 42 }) {
+            v = o[k];
+            log(k || v, v++);
+        }
+    }
+    expect_stdout: "foo 42"
+}
+
+issue_5638_4: {
+    options = {
+        collapse_vars: true,
+        hoist_vars: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var log = console.log;
+        var o = { foo: 6 };
+        for (var k in o) {
+            var v = o[k];
+            log(k || v, v *= 7);
+        }
+    }
+    expect: {
+        var log, o, k, v;
+        log = console.log;
+        for (k in o = { foo: 6 }) {
+            v = o[k];
+            log(k || v, v *= 7);
+        }
+    }
+    expect_stdout: "foo 42"
+}

test/compress/imports.js

@@ -40,6 +40,17 @@ default_keys: {
     expect_exact: 'import foo,{bar}from"baz";'
 }
 
+non_identifiers: {
+    beautify = {
+        quote_style: 3,
+    }
+    input: {
+        import { '42' as foo } from "bar";
+        import { "foo" as bar } from 'baz';
+    }
+    expect_exact: "import{'42'as foo}from\"bar\";import{foo as bar}from'baz';"
+}
+
 dynamic: {
     input: {
         (async a => await import(a))("foo").then(bar);
@@ -129,12 +140,12 @@ mangle: {
     }
     input: {
         import foo, { bar } from "baz";
-        consoe.log(moo);
+        console.log(moo);
         import * as moo from "moz";
     }
     expect: {
         import o, { bar as m } from "baz";
-        consoe.log(r);
+        console.log(r);
         import * as r from "moz";
     }
 }
@@ -146,16 +157,44 @@ rename_mangle: {
     }
     input: {
         import foo, { bar } from "baz";
-        consoe.log(moo);
+        console.log(moo);
         import * as moo from "moz";
     }
     expect: {
         import o, { bar as m } from "baz";
-        consoe.log(r);
+        console.log(r);
         import * as r from "moz";
     }
 }
 
+mangle_export_import: {
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        export let o = A;
+        import { p as A } from "foo";
+    }
+    expect: {
+        export let o = p;
+        import { p } from "foo";
+    }
+}
+
+mangle_import_export: {
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        import { p as A } from "foo";
+        export let o = A;
+    }
+    expect: {
+        import { p } from "foo";
+        export let o = p;
+    }
+}
+
 keep_ref: {
     options = {
         reduce_vars: true,
@@ -227,3 +266,33 @@ issue_4708_2: {
         import a from "foo";
     }
 }
+
+pr_5550_1: {
+    input: {
+        if (console)
+            import("foo");
+        else
+            import.meta.url.replace(/bar/g, console.log);
+    }
+    expect: {
+        if (console)
+            import("foo");
+        else
+            import.meta.url.replace(/bar/g, console.log);
+    }
+}
+
+pr_5550_2: {
+    input: {
+        L: {
+            import("foo");
+            import.meta.url.replace(/bar/g, console.log);
+        }
+    }
+    expect: {
+        L: {
+            import("foo");
+            import.meta.url.replace(/bar/g, console.log);
+        }
+    }
+}

test/compress/issue-1321.js

@@ -1,6 +1,7 @@
 issue_1321_no_debug: {
     mangle = {
         properties: {
+            domprops: true,
             keep_quoted: true,
         },
     }
@@ -23,6 +24,7 @@ issue_1321_debug: {
     mangle = {
         properties: {
             debug: "",
+            domprops: true,
             keep_quoted: true,
         },
     }
@@ -44,6 +46,7 @@ issue_1321_debug: {
 issue_1321_with_quoted: {
     mangle = {
         properties: {
+            domprops: true,
             keep_quoted: false,
         },
     }

test/compress/issue-143.js

@@ -1,5 +1,5 @@
 /**
- * There was an incorrect sort behaviour documented in issue #143:
+ * There was an incorrect sort behavior documented in issue #143:
  * (x = f(…)) <= x → x >= (x = f(…))
  *
  * For example, let the equation be:
@@ -12,37 +12,54 @@
  * a >= (a = parseInt('100')) → 99 >= 100 → false
  */
 
-tranformation_sort_order_equal: {
+transformation_sort_order_equal: {
     options = {
         comparisons: true,
     }
-
-    input: { (a = parseInt('100')) == a }
-    expect: { (a = parseInt('100')) == a }
+    input: {
+        console.log((a = parseInt("100")) == a);
+    }
+    expect: {
+        console.log((a = parseInt("100")) == a);
+    }
+    expect_stdout: "true"
 }
 
-tranformation_sort_order_unequal: {
+transformation_sort_order_unequal: {
     options = {
         comparisons: true,
     }
-
-    input: { (a = parseInt('100')) != a }
-    expect: { (a = parseInt('100')) != a }
+    input: {
+        console.log((a = parseInt("100")) != a);
+    }
+    expect: {
+        console.log((a = parseInt("100")) != a);
+    }
+    expect_stdout: "false"
 }
 
-tranformation_sort_order_lesser_or_equal: {
+transformation_sort_order_lesser_or_equal: {
     options = {
         comparisons: true,
     }
-
-    input: { (a = parseInt('100')) <= a }
-    expect: { (a = parseInt('100')) <= a }
+    input: {
+        console.log((a = parseInt("100")) <= a);
+    }
+    expect: {
+        console.log((a = parseInt("100")) <= a);
+    }
+    expect_stdout: "true"
 }
-tranformation_sort_order_greater_or_equal: {
+
+transformation_sort_order_greater_or_equal: {
     options = {
         comparisons: true,
     }
-
-    input: { (a = parseInt('100')) >= a }
-    expect: { (a = parseInt('100')) >= a }
-}
+    input: {
+        console.log((a = parseInt("100")) >= a);
+    }
+    expect: {
+        console.log((a = parseInt("100")) >= a);
+    }
+    expect_stdout: "true"
+}

test/compress/issue-1770.js

@@ -53,11 +53,21 @@ mangle_props: {
         );
     }
     expect_stdout: "1 1 1 2 2 2 3 3 3 4 4 4 5 5"
+    expect_warnings: [
+        "INFO: Preserving reserved property undefined",
+        "INFO: Preserving reserved property NaN",
+        "INFO: Preserving reserved property Infinity",
+        "INFO: Preserving reserved property -Infinity",
+        "INFO: Preserving reserved property null",
+        "INFO: Preserving reserved property log",
+    ]
 }
 
 numeric_literal: {
     mangle = {
-        properties: true,
+        properties: {
+            domprops: true,
+        },
     }
     beautify = {
         beautify: true,
@@ -106,11 +116,19 @@ numeric_literal: {
         "4 5 4 4",
         "8 7 8",
     ]
+    expect_warnings: [
+        "INFO: Mapping property 0x25 to o",
+        "INFO: Mapping property 1E42 to b",
+        "INFO: Preserving reserved property log",
+    ]
 }
 
 identifier: {
     mangle = {
-        properties: true,
+        properties: {
+            builtins: true,
+            domprops: true,
+        },
     }
     input: {
         var obj = {
@@ -209,37 +227,37 @@ identifier: {
             B: 28,
             C: 29,
             D: 30,
-            F: 31,
-            G: 32,
-            false: 33,
-            null: 34,
-            true: 35,
-            H: 36,
-            I: 37,
-            J: 38,
-            K: 39,
-            L: 40,
-            M: 41,
-            N: 42,
-            O: 43,
-            P: 44,
-            Q: 45,
-            R: 46,
-            S: 47,
-            T: 48,
-            U: 49,
-            V: 50,
-            W: 51,
-            X: 52,
-            Y: 53,
-            Z: 54,
-            $: 55,
-            _: 56,
-            ee: 57,
-            te: 58,
-            ne: 59,
-            ae: 60,
-            ie: 61,
+            E: 31,
+            F: 32,
+            G: 33,
+            H: 34,
+            I: 35,
+            J: 36,
+            K: 37,
+            L: 38,
+            M: 39,
+            N: 40,
+            O: 41,
+            P: 42,
+            Q: 43,
+            R: 44,
+            S: 45,
+            T: 46,
+            U: 47,
+            V: 48,
+            W: 49,
+            X: 50,
+            Y: 51,
+            Z: 52,
+            $: 53,
+            _: 54,
+            ee: 55,
+            te: 56,
+            ne: 57,
+            ae: 58,
+            ie: 59,
+            oe: 60,
+            re: 61,
         };
     }
 }

test/compress/issue-281.js

@@ -108,6 +108,7 @@ safe_undefined: {
 }
 
 negate_iife_3: {
+    expression = true
     options = {
         conditionals: true,
         expression: true,
@@ -123,6 +124,7 @@ negate_iife_3: {
 }
 
 negate_iife_3_off: {
+    expression = true
     options = {
         conditionals: true,
         expression: true,
@@ -203,6 +205,7 @@ negate_iife_5_off: {
 }
 
 issue_1254_negate_iife_true: {
+    expression = true
     options = {
         expression: true,
         inline: true,
@@ -215,11 +218,12 @@ issue_1254_negate_iife_true: {
             };
         })()();
     }
-    expect_exact: 'void console.log("test");'
+    expect_exact: 'void console.log("test")'
     expect_stdout: true
 }
 
 issue_1254_negate_iife_nested: {
+    expression = true
     options = {
         expression: true,
         inline: true,
@@ -232,7 +236,7 @@ issue_1254_negate_iife_nested: {
             };
         })()()()()();
     }
-    expect_exact: '(void console.log("test"))()()();'
+    expect_exact: '(void console.log("test"))()()()'
 }
 
 negate_iife_issue_1073: {

test/compress/issue-368.js

@@ -15,7 +15,7 @@ collapse: {
             var a;
             b = c();
             a = typeof b === 'function' ? b() : b;
-            return 'stirng' == typeof a && d();
+            return 'string' == typeof a && d();
         }
         function f3(c) {
             var a;
@@ -41,7 +41,7 @@ collapse: {
             return void 0 !== ('function' === typeof b ? b() : b) && c();
         }
         function f2(b) {
-            return 'stirng' == typeof ('function' === typeof (b = c()) ? b() : b) && d();
+            return 'string' == typeof ('function' === typeof (b = c()) ? b() : b) && d();
         }
         function f3(c) {
             var a;

test/compress/issue-5614.js

@@ -0,0 +1,195 @@
+record_update: {
+    options = {
+        loops: true,
+        passes: 3,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var value = { a: 42, b: "PASS" };
+        var unused = _Utils_update(value, { b: "FAIL" });
+        function _Utils_update(oldRecord, updatedFields) {
+            var newRecord = {};
+            for (var key in oldRecord)
+                newRecord[key] = oldRecord[key];
+            for (var key in updatedFields)
+                newRecord[key] = updatedFields[key];
+            return newRecord;
+        }
+    }
+    expect: {}
+}
+
+currying: {
+    options = {
+        inline: true,
+        passes: 3,
+        pure_getters: "strict",
+        reduce_funcs: true,
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function F(arity, fun, wrapper) {
+            wrapper.a = arity;
+            wrapper.f = fun;
+            return wrapper;
+        }
+        function F2(fun) {
+            return F(2, fun, function(a) {
+                return function(b) {
+                    return fun(a, b);
+                };
+            });
+        }
+        function _Utils_eq(x, y) {
+            var pair, stack = [], isEqual = _Utils_eqHelp(x, y, 0, stack);
+            while (isEqual && (pair = stack.pop()))
+                isEqual = _Utils_eqHelp(pair.a, pair.b, 0, stack);
+            return isEqual;
+        }
+        var _Utils_equal = F2(_Utils_eq);
+    }
+    expect: {}
+}
+
+conditional_property_write: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            var o = {};
+            if (a)
+                o.p = console.log("foo");
+            else
+                o.q = console.log("bar");
+            o.r = console.log("baz");
+        }
+        f(42);
+        f(null);
+    }
+    expect: {
+        function f(a) {
+            if (a)
+                console.log("foo");
+            else
+                console.log("bar");
+            console.log("baz");
+        }
+        f(42);
+        f(null);
+    }
+    expect_stdout: [
+        "foo",
+        "baz",
+        "bar",
+        "baz",
+    ]
+}
+
+reassign_1: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS", b = "FAIL";
+        (b = a).toString();
+        console.log(b);
+    }
+    expect: {
+        var b = "FAIL";
+        (b = "PASS").toString();
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+}
+
+reassign_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "PASS";
+        if (false) {
+            a = null + 0;
+            a();
+        }
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        if (false) {
+            a = 0;
+            a();
+        }
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+reassign_3: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 0;
+        (a = a || "PASS").toString();
+        console.log(a);
+    }
+    expect: {
+        var a = 0;
+        (a = (0, "PASS")).toString();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+retain_instance_write: {
+    options = {
+        pure_getters: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            return a;
+        }
+        function g() {
+            var o = {};
+            var b = new f(o);
+            if (console)
+                b.p = "PASS";
+            return o;
+        }
+        console.log(g().p);
+    }
+    expect: {
+        function f(a) {
+            return a;
+        }
+        function g() {
+            var o = {};
+            var b = new f(o);
+            if (console)
+                b.p = "PASS";
+            return o;
+        }
+        console.log(g().p);
+    }
+    expect_stdout: "PASS"
+}

test/compress/issue-640.js

@@ -68,6 +68,7 @@ drop_console_2: {
 }
 
 drop_value: {
+    expression = true
     options = {
         expression: true,
         side_effects: true,
@@ -106,6 +107,7 @@ wrongly_optimized: {
 }
 
 negate_iife_1: {
+    expression = true
     options = {
         expression: true,
         negate_iife: true,
@@ -119,6 +121,7 @@ negate_iife_1: {
 }
 
 negate_iife_3: {
+    expression = true
     options = {
         conditionals: true,
         expression: true,
@@ -133,6 +136,7 @@ negate_iife_3: {
 }
 
 negate_iife_3_off: {
+    expression = true
     options = {
         conditionals: true,
         expression: true,
@@ -215,6 +219,7 @@ negate_iife_5_off: {
 }
 
 issue_1254_negate_iife_true: {
+    expression = true
     options = {
         expression: true,
         negate_iife: true,
@@ -226,11 +231,12 @@ issue_1254_negate_iife_true: {
             };
         })()();
     }
-    expect_exact: '(function(){return function(){console.log("test")}})()();'
+    expect_exact: 'function(){return function(){console.log("test")}}()()'
     expect_stdout: true
 }
 
 issue_1254_negate_iife_nested: {
+    expression = true
     options = {
         expression: true,
         negate_iife: true,
@@ -242,7 +248,7 @@ issue_1254_negate_iife_nested: {
             };
         })()()()()();
     }
-    expect_exact: '(function(){return function(){console.log("test")}})()()()()();'
+    expect_exact: 'function(){return function(){console.log("test")}}()()()()()'
     expect_stdout: true
 }
 

test/compress/issue-747.js

@@ -1,6 +1,7 @@
 dont_reuse_prop: {
     mangle = {
         properties: {
+            domprops: true,
             regex: /asd/,
         },
     }
@@ -19,11 +20,17 @@ dont_reuse_prop: {
         console.log(obj.a);
     }
     expect_stdout: "123"
+    expect_warnings: [
+        "INFO: Preserving excluded property a",
+        "INFO: Mapping property asd to b",
+        "INFO: Preserving reserved property log",
+    ]
 }
 
 unmangleable_props_should_always_be_reserved: {
     mangle = {
         properties: {
+            domprops: true,
             regex: /asd/,
         },
     }
@@ -42,4 +49,9 @@ unmangleable_props_should_always_be_reserved: {
         console.log(obj.a);
     }
     expect_stdout: "123"
+    expect_warnings: [
+        "INFO: Preserving excluded property a",
+        "INFO: Mapping property asd to b",
+        "INFO: Preserving reserved property log",
+    ]
 }

test/compress/issue-913.js

@@ -1,17 +1,18 @@
 keep_var_for_in: {
     options = {
         hoist_vars: true,
+        join_vars: true,
         unused: true,
     }
     input: {
-        (function(obj){
+        (function(obj) {
             var foo = 5;
             for (var i in obj)
                 return foo;
         })();
     }
     expect: {
-        (function(obj){
+        (function(obj) {
             var i, foo = 5;
             for (i in obj)
                 return foo;

test/compress/join_vars.js

@@ -16,6 +16,105 @@ join_vars_assign: {
     expect_stdout: "PASS"
 }
 
+join_array_assignments_1: {
+    options = {
+        evaluate: true,
+        join_vars: true,
+    }
+    input: {
+        console.log(function () {
+            var a = [ "foo", , "bar" ];
+            a[1] = "baz";
+            a[7] = "moo";
+            a[0] = "moz";
+            return a;
+        }().join());
+    }
+    expect: {
+        console.log(function () {
+            var a = [ "moz", "baz", "bar", , , , , "moo" ];
+            return a;
+        }().join());
+    }
+    expect_stdout: "moz,baz,bar,,,,,moo"
+}
+
+join_array_assignments_2: {
+    options = {
+        evaluate: true,
+        join_vars: true,
+    }
+    input: {
+        console.log(function () {
+            var a = [ "foo" ];
+            a[1] = "bar";
+            a[7] = "baz";
+            a[2] = "moo";
+            return a;
+        }().join());
+    }
+    expect: {
+        console.log(function () {
+            var a = [ "foo", "bar" ];
+            a[7] = "baz";
+            a[2] = "moo";
+            return a;
+        }().join());
+    }
+    expect_stdout: "foo,bar,moo,,,,,baz"
+}
+
+join_array_assignments_3: {
+    options = {
+        evaluate: true,
+        join_vars: true,
+    }
+    input: {
+        console.log(function () {
+            var a = [ "foo" ];
+            a[1] = "bar";
+            a.b = "baz";
+            a[2] = "moo";
+            return a;
+        }().join());
+    }
+    expect: {
+        console.log(function () {
+            var a = [ "foo", "bar" ];
+            a.b = "baz";
+            a[2] = "moo";
+            return a;
+        }().join());
+    }
+    expect_stdout: true
+}
+
+join_array_assignments_4: {
+    options = {
+        evaluate: true,
+        join_vars: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(function () {
+            var a = [ "foo" ];
+            a[0] = "bar";
+            a[1] = a;
+            a[2] = "baz";
+            return a;
+        }().join());
+    }
+    expect: {
+        console.log(function () {
+            var a = [ "bar" ];
+            a[1] = a;
+            a[2] = "baz";
+            return a;
+        }().join());
+    }
+    expect_stdout: true
+}
+
 join_object_assignments_1: {
     options = {
         evaluate: true,
@@ -570,7 +669,7 @@ inlined_assignments: {
     expect_stdout: "PASS"
 }
 
-inilne_for: {
+inline_for: {
     options = {
         inline: true,
         join_vars: true,
@@ -590,7 +689,7 @@ inilne_for: {
     expect_stdout: "PASS"
 }
 
-inilne_var: {
+inline_var: {
     options = {
         inline: true,
         join_vars: true,
@@ -1394,3 +1493,37 @@ issue_5175: {
     }
     expect_stdout: "PASS PASS"
 }
+
+issue_5831: {
+    options = {
+        evaluate: true,
+        join_vars: true,
+    }
+    input: {
+        var a = [ console.log("PASS") ];
+        a[0] = 42;
+    }
+    expect: {
+        var a = [ (console.log("PASS"), 42) ];
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5849: {
+    options = {
+        evaluate: true,
+        join_vars: true,
+        side_effects: true,
+    }
+    input: {
+        var a;
+        a = [ 42 ];
+        a[0] = "PASS";
+        console.log(a.join(""));
+    }
+    expect: {
+        var a, a = [ "PASS" ];
+        console.log(a.join(""));
+    }
+    expect_stdout: "PASS"
+}

test/compress/labels.js

@@ -111,6 +111,7 @@ labels_5: {
 labels_6: {
     options = {
         dead_code: true,
+        unused: true,
     }
     input: {
         out: break out;
@@ -208,6 +209,59 @@ labels_10: {
     expect_stdout: "PASS"
 }
 
+labels_11: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        unused: true,
+    }
+    input: {
+        L: if (console.log("PASS"))
+            break L;
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+labels_12: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        if_return: true,
+    }
+    input: {
+        L: try {
+            if (console.log("foo"))
+                break L;
+            throw "bar";
+        } catch (e) {
+            console.log(e);
+            break L;
+        } finally {
+            if (console.log("baz"))
+                break L;
+        }
+    }
+    expect: {
+        L: try {
+            if (!console.log("foo"))
+                throw "bar";
+        } catch (e) {
+            console.log(e);
+        } finally {
+            if (console.log("baz"))
+                break L;
+        }
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+        "baz",
+    ]
+}
+
 issue_4466_1: {
     mangle = {
         v8: false,
@@ -327,3 +381,53 @@ issue_4466_2_toplevel_v8: {
     }
     expect_stdout: "PASS"
 }
+
+issue_5522: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        console.log(function() {
+            L: try {
+                return "FAIL";
+            } finally {
+                break L;
+            }
+            return "PASS";
+        }());
+    }
+    expect: {
+        console.log(function() {
+            L: try {
+                return "FAIL";
+            } finally {
+                break L;
+            }
+            return "PASS";
+        }());
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5524: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        L: try {
+            FAIL;
+        } finally {
+            break L;
+        }
+        console.log("PASS");
+    }
+    expect: {
+        L: try {
+            FAIL;
+        } finally {
+            break L;
+        }
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}

test/compress/let.js

@@ -190,6 +190,96 @@ if_dead_branch: {
     node_version: ">=4"
 }
 
+retain_tail_1: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        "use strict";
+        function f(a) {
+            var b = "foo";
+            if (a) {
+                let b = "bar";
+                while (console.log("baz"));
+                console.log(b);
+            } else {
+                while (console.log("moo"));
+                console.log(b);
+            }
+        }
+        f();
+        f(42);
+    }
+    expect: {
+        "use strict";
+        function f(a) {
+            var b = "foo";
+            if (a) {
+                let b = "bar";
+                while (console.log("baz"));
+                console.log(b);
+            } else {
+                while (console.log("moo"));
+                console.log(b);
+            }
+        }
+        f();
+        f(42);
+    }
+    expect_stdout: [
+        "moo",
+        "foo",
+        "baz",
+        "bar",
+    ]
+    node_version: ">=4"
+}
+
+retain_tail_2: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        "use strict";
+        function f(a) {
+            var b = "foo";
+            if (a) {
+                while (console.log("bar"));
+                console.log(b);
+            } else {
+                let b = "baz";
+                while (console.log("moo"));
+                console.log(b);
+            }
+        }
+        f();
+        f(42);
+    }
+    expect: {
+        "use strict";
+        function f(a) {
+            var b = "foo";
+            if (a) {
+                while (console.log("bar"));
+                console.log(b);
+            } else {
+                let b = "baz";
+                while (console.log("moo"));
+                console.log(b);
+            }
+        }
+        f();
+        f(42);
+    }
+    expect_stdout: [
+        "moo",
+        "baz",
+        "bar",
+        "foo",
+    ]
+    node_version: ">=4"
+}
+
 merge_vars_1: {
     options = {
         merge_vars: true,
@@ -892,6 +982,40 @@ if_return_2: {
     node_version: ">=4"
 }
 
+if_return_3: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        "use strict";
+        var a = "PASS";
+        function f(b) {
+            if (console) {
+                let b = a;
+                return b;
+            } else
+                while (console.log("FAIL 1"));
+            return b;
+        }
+        console.log(f("FAIL 2"));
+    }
+    expect: {
+        "use strict";
+        var a = "PASS";
+        function f(b) {
+            if (console) {
+                let b = a;
+                return b;
+            } else
+                while (console.log("FAIL 1"));
+            return b;
+        }
+        console.log(f("FAIL 2"));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
 do_if_continue_1: {
     options = {
         if_return: true,
@@ -1006,6 +1130,130 @@ default_init: {
     node_version: ">=4"
 }
 
+join_let_var_1: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        var a = "foo";
+        let b = "bar";
+        for (var c of [ a, b ])
+            console.log(c);
+    }
+    expect: {
+        "use strict";
+        let a = "foo", b = "bar";
+        for (var c of [ a, b ])
+            console.log(c);
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=4"
+}
+
+join_let_var_2: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        let a = "foo";
+        var b = "bar";
+        for (let c of [ a, b ])
+            console.log(c);
+    }
+    expect: {
+        "use strict";
+        let a = "foo", b = "bar";
+        for (let c of [ a, b ])
+            console.log(c);
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    node_version: ">=4"
+}
+
+keep_let_var_1: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        var a = "foo";
+        let b = "bar";
+        for (var c of [ a, b ])
+            console.log(c);
+        function f() {
+            return a;
+        }
+        console.log(f(f));
+    }
+    expect: {
+        "use strict";
+        var a = "foo", c;
+        let b = "bar";
+        for (c of [ a, b ])
+            console.log(c);
+        function f() {
+            return a;
+        }
+        console.log(f(f));
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+        "foo",
+    ]
+    node_version: ">=4"
+}
+
+keep_let_var_2: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        let a = "foo";
+        var b = "bar";
+        for (let c of [ a, b ])
+            console.log(c);
+        function f() {
+            return b;
+        }
+        console.log(f(f));
+    }
+    expect: {
+        "use strict";
+        let a = "foo";
+        var b = "bar";
+        for (let c of [ a, b ])
+            console.log(c);
+        function f() {
+            return b;
+        }
+        console.log(f(f));
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+        "bar",
+    ]
+    node_version: ">=4"
+}
+
 issue_4191: {
     options = {
         functions: true,
@@ -1625,7 +1873,7 @@ issue_4438: {
         function f() {
             if (console) {
                 let a = console.log;
-                void a("PASS");
+                a("PASS");
             }
         }
         f();
@@ -1998,3 +2246,323 @@ issue_5476: {
     expect_stdout: "undefined"
     node_version: ">=4"
 }
+
+issue_5591: {
+    options = {
+        dead_code: true,
+        if_return: true,
+    }
+    input: {
+        "use strict";
+        function f(a) {
+            switch (console.log("foo")) {
+              case console.log("bar"):
+                if (console.log("baz"))
+                    return;
+                else {
+                    let a;
+                    return;
+                }
+                break;
+              case null:
+                FAIL;
+            }
+        }
+        f();
+    }
+    expect: {
+        "use strict";
+        function f(a) {
+            switch (console.log("foo")) {
+              case console.log("bar"):
+                if (console.log("baz"))
+                    return;
+                else {
+                    let a;
+                    return;
+                }
+              case null:
+                FAIL;
+            }
+        }
+        f();
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+        "baz",
+    ]
+    node_version: ">=4"
+}
+
+issue_5741: {
+    options = {
+        inline: true,
+        join_vars: true,
+        reduce_vars: true,
+    }
+    input: {
+        "use strict";
+        (function(a) {
+            let b = function() {
+                var c = a;
+                console.log(c);
+            }();
+            function g() {
+                a++;
+                b;
+            }
+        })("PASS");
+    }
+    expect: {
+        "use strict";
+        (function(a) {
+            let b = (c = a, void console.log(c));
+            var c;
+            function g() {
+                a++;
+                b;
+            }
+        })("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5745_1: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        {
+            let f = function() {
+                return f && "PASS";
+            };
+            var a = f();
+        }
+        a;
+        console.log(a);
+    }
+    expect: {
+        "use strict";
+        {
+            let f = function() {
+                return f && "PASS";
+            };
+            var a = f();
+        }
+        a;
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5745_2: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        {
+            let f = function() {
+                return f && "PASS";
+            };
+            var a = f();
+            a;
+            console.log(a);
+        }
+    }
+    expect: {
+        "use strict";
+        {
+            let f = function() {
+                return f && "PASS";
+            }, a = f();
+            a;
+            console.log(a);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5756_1: {
+    options = {
+        join_vars: true,
+        loops: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        do {
+            function f() {
+                return b;
+            }
+            var a = "PASS".toString();
+            let b;
+            console.log(a);
+        } while (!console);
+    }
+    expect: {
+        "use strict";
+        do {
+            function f() {
+                return b;
+            }
+            let a = "PASS".toString(), b;
+            console.log(a);
+        } while (!console);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5756_2: {
+    options = {
+        join_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        function f() {
+            let a = console.log("PASS");
+            {
+                var b;
+                for (var c in b) {
+                    b;
+                    var c = function() {
+                        a;
+                    };
+                }
+            }
+        }
+        f();
+    }
+    expect: {
+        "use strict";
+        (function() {
+            let a = console.log("PASS"), b;
+            for (c in b) {
+                b;
+                var c = function() {
+                    a;
+                };
+            }
+        })();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5756_3: {
+    options = {
+        module: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        console.log(f()());
+        function f() {
+            const a = "PASS";
+            return function() {
+                return a;
+            };
+        }
+    }
+    expect: {
+        "use strict";
+        console.log(function() {
+            let a = "PASS";
+            return function() {
+                return a;
+            };
+        }()());
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5759: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        join_vars: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        function f() {
+            for (var a in [ true ]) {
+                let b;
+                (function() {
+                    var c = void 0;
+                    b;
+                    console.log(c);
+                    var d = null;
+                    console.log(c);
+                })();
+            }
+        }
+        f();
+    }
+    expect: {
+        "use strict";
+        function f() {
+            for (var a in [ true ]) {
+                let b;
+                var c = c = void 0;
+                b;
+                console.log(c);
+                console.log(c);
+            }
+        }
+        f();
+    }
+    expect_stdout: [
+        "undefined",
+        "undefined",
+    ]
+    node_version: ">=4"
+}
+
+issue_5787: {
+    options = {
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            let a = 42;
+            switch (a) {
+              case 42:
+                // Node.js v4 (vm): SyntaxError: Identifier 'a' has already been declared
+                let a = "PASS";
+                return a;
+            }
+        }());
+    }
+    expect: {
+        console.log(function() {
+            let a = 42;
+            switch (a) {
+              case 42:
+                let a = "PASS";
+                return a;
+            }
+        }());
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}

test/compress/merge_vars.js

@@ -3845,3 +3845,158 @@ issue_5471_2: {
     }
     expect_stdout: "PASS"
 }
+
+issue_5714: {
+    options = {
+        inline: true,
+        join_vars: true,
+        loops: true,
+        merge_vars: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        console.log(function() {
+            var i = 1;
+            while (i--) {
+                var a = function f(b) {
+                    console.log(b);
+                    var c = function(d) {
+                        console.log(typeof d);
+                    }(console);
+                }();
+                var e = 42;
+            }
+            return e;
+        }());
+    }
+    expect: {
+        "use strict";
+        console.log(function() {
+            for (var i = 1; i--;) {
+                var b = void 0;
+                console.log(b);
+                b = console,
+                console.log(typeof b);
+                var e = 42;
+            }
+            return e;
+        }());
+    }
+    expect_stdout: [
+        "undefined",
+        "object",
+        "42",
+    ]
+}
+
+issue_5770_1: {
+    options = {
+        dead_code: true,
+        loops: true,
+        merge_vars: true,
+        toplevel: true,
+    }
+    input: {
+        L: do {
+            if (console)
+                for (var a = "FAIL 1"; a; a--)
+                    continue L;
+            var b = "FAIL 2";
+        } while (console.log(b || "PASS"));
+    }
+    expect: {
+        L: do {
+            if (console) {
+                var a = "FAIL 1";
+                if (a)
+                    continue L;
+            }
+            var b = "FAIL 2";
+        } while (console.log(b || "PASS"));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5770_2: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        if_return: true,
+        loops: true,
+        merge_vars: true,
+        toplevel: true,
+    }
+    input: {
+        L: do {
+            for (var a = "FAIL 1"; a; a--)
+                continue L;
+            var b = "FAIL 2";
+        } while (console.log(b || "PASS"));
+    }
+    expect: {
+        L: do {
+            var a = "FAIL 1";
+            var b;
+        } while (a || (b = "FAIL 2"), console.log(b || "PASS"));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5772_1: {
+    options = {
+        dead_code: true,
+        merge_vars: true,
+        loops: true,
+    }
+    input: {
+        (function(a) {
+            while (--a)
+                return;
+            var b = console.log("foo") && (c = 42) ? 0 : console.log(c);
+            var c = b;
+        })();
+    }
+    expect: {
+        (function(a) {
+            if (--a)
+                return;
+            var a = console.log("foo") && (c = 42) ? 0 : console.log(c);
+            var c = a;
+        })();
+    }
+    expect_stdout: [
+        "foo",
+        "undefined",
+    ]
+}
+
+issue_5772_2: {
+    options = {
+        dead_code: true,
+        merge_vars: true,
+        loops: true,
+    }
+    input: {
+        (function(a) {
+            while (--a)
+                return;
+            var b;
+            var c = console.log("foo") && (b = 1) ? 2 : 3;
+            console.log(b, c);
+        })();
+    }
+    expect: {
+        (function(a) {
+            if (--a)
+                return;
+            var b;
+            var a = console.log("foo") && (b = 1) ? 2 : 3;
+            console.log(b, a);
+        })();
+    }
+    expect_stdout: [
+        "foo",
+        "undefined 3",
+    ]
+}

test/compress/nullish.js

@@ -308,6 +308,7 @@ issue_4679: {
 issue_5266: {
     options = {
         inline: true,
+        side_effects: true,
     }
     input: {
         [
@@ -343,3 +344,43 @@ issue_5266: {
     ]
     node_version: ">=14"
 }
+
+issue_5829_1: {
+    options = {
+        merge_vars: true,
+    }
+    input: {
+        (function f(a) {
+            var b;
+            (!a ?? (b = 0)) || console.log(b || "PASS");
+        })("FAIL");
+    }
+    expect: {
+        (function f(a) {
+            var b;
+            (!a ?? (b = 0)) || console.log(b || "PASS");
+        })("FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=14"
+}
+
+issue_5829_2: {
+    options = {
+        merge_vars: true,
+    }
+    input: {
+        (function f(a) {
+            var b;
+            (a ?? (b = 0)) && console.log(b || "PASS");
+        })("FAIL");
+    }
+    expect: {
+        (function f(a) {
+            var b;
+            (a ?? (b = 0)) && console.log(b || "PASS");
+        })("FAIL");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=14"
+}

test/compress/objects.js

@@ -173,7 +173,9 @@ numeric_literal: {
         side_effects: true,
     }
     mangle = {
-        properties: true,
+        properties: {
+            domprops: true,
+        },
     }
     beautify = {
         beautify: true,

test/compress/optional-chains.js

@@ -617,3 +617,33 @@ issue_5292_sub_pure_getters_strict: {
     ]
     node_version: ">=14"
 }
+
+issue_5856: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        try {
+            var a;
+            a?.p;
+            a.q;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            var a;
+            a?.p;
+            a.q;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=14"
+}

test/compress/properties.js

@@ -133,6 +133,7 @@ evaluate_string_length: {
 mangle_properties_1: {
     mangle = {
         properties: {
+            domprops: true,
             keep_quoted: false,
         },
     }
@@ -147,17 +148,18 @@ mangle_properties_1: {
         a["a"] = "bar";
         a.b = "red";
         x = {o: 10};
-        a.r(x.o, a.a);
-        a['r']({b: "blue", a: "baz"});
+        a.run(x.o, a.a);
+        a['run']({b: "blue", a: "baz"});
     }
 }
 
 mangle_properties_2: {
     mangle = {
         properties: {
+            domprops: true,
             reserved: [
                 "value",
-            ]
+            ],
         },
     }
     input: {
@@ -199,6 +201,24 @@ mangle_properties_2: {
     ]
 }
 
+mangle_properties_3: {
+    mangle = {
+        properties: true,
+    }
+    input: {
+        console.log({
+            [(console, "foo")]: "PASS",
+        }.foo);
+    }
+    expect: {
+        console.log({
+            [(console, "o")]: "PASS",
+        }.o);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
 mangle_unquoted_properties: {
     options = {
         evaluate: true,
@@ -206,6 +226,8 @@ mangle_unquoted_properties: {
     }
     mangle = {
         properties: {
+            builtins: true,
+            domprops: true,
             keep_quoted: true,
         },
     }
@@ -305,7 +327,9 @@ mangle_debug_suffix_keep_quoted: {
     }
     mangle = {
         properties: {
+            builtins: true,
             debug: "XYZ",
+            domprops: true,
             keep_quoted: true,
             reserved: [],
         },
@@ -351,6 +375,68 @@ mangle_debug_suffix_keep_quoted: {
     }
 }
 
+keep_substituted_property: {
+    options = {
+        evaluate: true,
+        properties: true,
+        reduce_vars: true,
+    }
+    mangle = {
+        properties: {
+            keep_quoted: true,
+        },
+    }
+    input: {
+        var o = { p: [] };
+        function f(b) {
+            return o[b];
+        }
+        function g() {
+            var a = "p";
+            return o[a] === f(a);
+        }
+        console.log(g() ? "PASS" : "FAIL");
+    }
+    expect: {
+        var o = { p: [] };
+        function f(n) {
+            return o[n];
+        }
+        function g() {
+            var n = "p";
+            return o.p === f(n);
+        }
+        console.log(g() ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+keep_substituted_property_quotes: {
+    options = {
+        evaluate: true,
+        properties: true,
+        reduce_vars: true,
+    }
+    beautify = {
+        keep_quoted_props: true,
+    }
+    input: {
+        function f(o) {
+            var a = "p";
+            return o[a];
+        }
+        console.log(f({ p: "PASS" }));
+    }
+    expect: {
+        function f(o) {
+            var a = "p";
+            return o["p"];
+        }
+        console.log(f({ p: "PASS" }));
+    }
+    expect_stdout: "PASS"
+}
+
 first_256_chars_as_properties: {
     beautify = {
         ascii_only: true,
@@ -897,12 +983,15 @@ issue_2256: {
         },
     }
     input: {
-        ({ "keep": 1 });
-        g.keep = g.change;
+        ({ "keep": 42 });
+        global.keep = global.change = "PASS";
+        console.log(keep);
     }
     expect: {
-        g.keep = g.g;
+        global.keep = global.l = "PASS";
+        console.log(keep);
     }
+    expect_stdout: "PASS"
 }
 
 lhs_prop_1: {
@@ -1578,3 +1667,163 @@ issue_5177: {
     expect_stdout: "PASS"
     node_version: ">=4"
 }
+
+issue_5682_in_1: {
+    mangle = {
+        properties: true,
+    }
+    input: {
+        function f(a) {
+            return "foo" in a;
+        }
+        var o = {};
+        var p = "foo";
+        o[p] = 42;
+        console.log(f(o) ? "PASS" : "FAIL");
+    }
+    expect: {
+        function f(o) {
+            return "foo" in o;
+        }
+        var o = {};
+        var p = "foo";
+        o[p] = 42;
+        console.log(f(o) ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5682_in_2: {
+    mangle = {
+        properties: true,
+    }
+    input: {
+        function f(a) {
+            return "foo" in a;
+        }
+        var o = { foo: 42 };
+        console.log(f(o) ? "PASS" : "FAIL");
+    }
+    expect: {
+        function f(o) {
+            return "o" in o;
+        }
+        var o = { o: 42 };
+        console.log(f(o) ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5682_dot_1: {
+    mangle = {
+        properties: true,
+    }
+    input: {
+        function f(a) {
+            return a.foo;
+        }
+        var o = {};
+        var p = "foo";
+        o[p] = "PASS";
+        console.log(f(o));
+    }
+    expect: {
+        function f(o) {
+            return o.foo;
+        }
+        var o = {};
+        var p = "foo";
+        o[p] = "PASS";
+        console.log(f(o));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5682_dot_2: {
+    mangle = {
+        properties: true,
+    }
+    input: {
+        function f(a) {
+            return a.foo;
+        }
+        var o = { foo: "PASS" };
+        console.log(f(o));
+    }
+    expect: {
+        function f(o) {
+            return o.o;
+        }
+        var o = { o: "PASS" };
+        console.log(f(o));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5682_dot_2_computed: {
+    mangle = {
+        properties: true,
+    }
+    input: {
+        function f(a) {
+            return a.foo;
+        }
+        var o = { ["foo"]: "PASS" };
+        console.log(f(o));
+    }
+    expect: {
+        function f(o) {
+            return o.o;
+        }
+        var o = { ["o"]: "PASS" };
+        console.log(f(o));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5682_sub_1: {
+    mangle = {
+        properties: true,
+    }
+    input: {
+        function f(a) {
+            return a["foo"];
+        }
+        var o = {};
+        var p = "foo";
+        o[p] = "PASS";
+        console.log(f(o));
+    }
+    expect: {
+        function f(o) {
+            return o["foo"];
+        }
+        var o = {};
+        var p = "foo";
+        o[p] = "PASS";
+        console.log(f(o));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5682_sub_2: {
+    mangle = {
+        properties: true,
+    }
+    input: {
+        function f(a) {
+            return a["foo"];
+        }
+        var o = { foo: "PASS" };
+        console.log(f(o));
+    }
+    expect: {
+        function f(o) {
+            return o["o"];
+        }
+        var o = { o: "PASS" };
+        console.log(f(o));
+    }
+    expect_stdout: "PASS"
+}

test/compress/pure_funcs.js

@@ -147,7 +147,7 @@ relational: {
         "bar" >= "bar";
     }
     expect: {
-        0 instanceof bar();
+        [] instanceof bar();
         bar();
         bar(), bar();
         bar();

test/compress/pure_getters.js

@@ -1540,10 +1540,12 @@ this_toString: {
 issue_4803: {
     options = {
         hoist_vars: true,
+        join_vars: true,
         pure_getters: "strict",
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
+        unused: true,
     }
     input: {
         var o = {
@@ -1685,3 +1687,31 @@ issue_4939: {
     }
     expect_stdout: "PASS"
 }
+
+issue_5856: {
+    options = {
+        pure_getters: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = [ "FAIL", "PASS" ];
+        (function(b) {
+            var c = b[0];
+            b[0] = b[1];
+            b[1] = c;
+        })(a);
+        console.log(a[0]);
+    }
+    expect: {
+        var a = [ "FAIL", "PASS" ];
+        (function(b) {
+            var c = b[0];
+            b[0] = b[1];
+            b[1] = c;
+        })(a);
+        console.log(a[0]);
+    }
+    expect_stdout: "PASS"
+}

test/compress/reduce_vars.js

@@ -2488,7 +2488,7 @@ side_effects_assign: {
         console.log(a);
     }
     expect: {
-        var a = typeof void (a && a.in);
+        var a = "undefined";
         console.log(a);
     }
     expect_stdout: "undefined"
@@ -2530,7 +2530,8 @@ pure_getters_2: {
         var a = a && a.b;
     }
     expect: {
-        var a = a && a.b;
+        var a;
+        a && a.b;
     }
 }
 
@@ -5424,7 +5425,7 @@ issue_2774: {
             get a() {
                 var b;
                 (b = true) && b.c;
-                b = void 0;
+                void 0;
             }
         }.a);
     }
@@ -7896,3 +7897,452 @@ issue_5434: {
     }
     expect_stdout: "PASS"
 }
+
+issue_5623: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 0;
+        function f() {
+            var b = a;
+            a = b;
+        }
+        f && f((a++ && a).toString());
+        console.log(a);
+    }
+    expect: {
+        var a = 0;
+        function f() {
+            var b;
+            a = a;
+        }
+        f((a++ && a).toString());
+        console.log(a);
+    }
+    expect_stdout: "1"
+}
+
+issue_5716_1: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        merge_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        function f() {
+            var b = [ c, c ], c = function() {
+                return b++ + (a = b);
+            }();
+        }
+        f();
+        console.log(a);
+    }
+    expect: {
+        c = [ c, c ],
+        void (c = ++c);
+        var c;
+        console.log(c);
+    }
+    expect_stdout: "NaN"
+}
+
+issue_5716_2: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        merge_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        function f() {
+            var b = [ c, c ], c = function() {
+                return (b += 4) + (a = b += 2);
+            }();
+        }
+        f();
+        console.log(a);
+    }
+    expect: {
+        void (c = c = (c = [ c, c ]) + 4 + 2);
+        var c;
+        console.log(c);
+    }
+    expect_stdout: ",42"
+}
+
+issue_5716_3: {
+    options = {
+        assignments: true,
+        collapse_vars: true,
+        inline: true,
+        merge_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        function f() {
+            var b = [ c, c ], c = function() {
+                return (b = b + 4) + (a = b += 2);
+            }();
+        }
+        f();
+        console.log(a);
+    }
+    expect: {
+        void (c = c = (c = [ c, c ]) + 4 + 2);
+        var c;
+        console.log(c);
+    }
+    expect_stdout: ",42"
+}
+
+issue_5716_4: {
+    options = {
+        assignments: true,
+        collapse_vars: true,
+        inline: true,
+        merge_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        function f() {
+            var b = [ c, c ], c = function() {
+                return (b = true | b) + (a = b *= 42);
+            }();
+        }
+        f();
+        console.log(a);
+    }
+    expect: {
+        void (c = c = ((c = [ c, c ]) | true) * 42);
+        var c;
+        console.log(c);
+    }
+    expect_stdout: "42"
+}
+
+issue_5716_5: {
+    options = {
+        assignments: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function() {
+            return 0 || (a = 42 | a);
+            var a = function() {
+                return a;
+            };
+        }());
+    }
+    expect: {
+        console.log(function() {
+            return 0 || (a |= 42);
+            var a = function() {
+                return a;
+            };
+        }());
+    }
+    expect_stdout: "42"
+}
+
+issue_5730_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        L: {
+            var f = function() {
+                console.log(a);
+            };
+        }
+        f();
+        a++;
+    }
+    expect: {
+        var a = "PASS";
+        var f = function() {
+            console.log(a);
+        };
+        f();
+        a++;
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5730_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        try {
+            var f = function() {
+                console.log(a);
+            };
+        } finally {}
+        f();
+        a++;
+    }
+    expect: {
+        var a = "PASS";
+        try {
+            var f = function() {
+                console.log(a);
+            };
+        } finally {}
+        f();
+        a++;
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5730_3: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var f, a = "PASS";
+        L: {
+            f = function() {
+                console.log(a);
+            };
+        }
+        f();
+        a++;
+    }
+    expect: {
+        var f, a = "PASS";
+        f = function() {
+            console.log(a);
+        };
+        f();
+        a++;
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5777_1: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            (function(a) {
+                function g() {
+                    h();
+                }
+                g();
+                a = function() {};
+                function h() {
+                    console.log(a);
+                }
+            })("PASS");
+        }
+        f();
+    }
+    expect: {
+        function f() {
+            (function(a) {
+                (function() {
+                    h();
+                })();
+                a = function() {};
+                function h() {
+                    console.log(a);
+                }
+            })("PASS");
+        }
+        f();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5777_2: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            (function() {
+                function g() {
+                    h();
+                }
+                g();
+                a = function() {};
+                function h() {
+                    console.log(a);
+                }
+            })();
+        }
+        f("PASS");
+    }
+    expect: {
+        (function(a) {
+            (function() {
+                (function() {
+                    h();
+                })();
+                a = function() {};
+                function h() {
+                    console.log(a);
+                }
+            })();
+        })("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_1666: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var x = 42;
+        {
+            x();
+            function x() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof x);
+    }
+    expect: {
+        var x = 42;
+        {
+            x();
+            function x() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof x);
+    }
+    expect_stdout: true
+}
+
+issue_1666_strict: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        var x = 42;
+        {
+            x();
+            function x() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof x);
+    }
+    expect: {
+        "use strict";
+        var x = 42;
+        {
+            x();
+            function x() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof x);
+    }
+    expect_stdout: true
+}
+
+issue_1666_undefined: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var undefined = 42;
+        {
+            undefined();
+            function undefined() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof undefined);
+    }
+    expect: {
+        var undefined = 42;
+        {
+            undefined();
+            function undefined() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof undefined);
+    }
+    expect_stdout: true
+}
+
+issue_1666_undefined_strict: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        var undefined = 42;
+        {
+            undefined();
+            function undefined() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof undefined);
+    }
+    expect: {
+        "use strict";
+        var undefined = 42;
+        {
+            undefined();
+            function undefined() {
+                console.log("foo");
+            }
+        }
+        console.log(typeof undefined);
+    }
+    expect_stdout: true
+}

test/compress/rename.js

@@ -739,3 +739,55 @@ issue_3480_ie8_toplevel: {
     }
     expect_stdout: "PASS"
 }
+
+issue_5787_1: {
+    rename = true
+    input: {
+        console.log(function() {
+            const a = 42;
+            switch (a) {
+              case 42:
+                const a = "PASS";
+                return a;
+            }
+        }());
+    }
+    expect: {
+        console.log(function() {
+            const a = 42;
+            switch (a) {
+              case 42:
+                const a = "PASS";
+                return a;
+            }
+        }());
+    }
+    expect_stdout: true
+}
+
+issue_5787_2: {
+    rename = true
+    input: {
+        console.log(function() {
+            let a = 42;
+            switch (a) {
+              case 42:
+                // Node.js v4 (vm): SyntaxError: Identifier 'a' has already been declared
+                let a = "PASS";
+                return a;
+            }
+        }());
+    }
+    expect: {
+        console.log(function() {
+            let a = 42;
+            switch (a) {
+              case 42:
+                let b = "PASS";
+                return b;
+            }
+        }());
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}

test/compress/rests.js

@@ -648,7 +648,7 @@ drop_new_function: {
     }
     expect: {
         void ([ ... {
-            [console.log("PASS")]: [].e,
+            [console.log("PASS")]: [][0],
         }] = []);
     }
     expect_stdout: "PASS"
@@ -1363,3 +1363,282 @@ issue_5391: {
     expect_stdout: "NaN"
     node_version: ">=8.3.0"
 }
+
+issue_5533_1_keep_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(...b) {
+                            b;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_1_drop_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: false,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(...b) {
+                            b;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_2_keep_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: true,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(...[ b ]) {
+                            b;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5533_2_drop_fargs: {
+    options = {
+        evaluate: true,
+        inline: true,
+        join_vars: true,
+        keep_fargs: false,
+        loops: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        try {
+            (function() {
+                var a;
+                for (; 1;)
+                    a = function() {
+                        (function f(...[ b ]) {
+                            b;
+                            throw "PASS";
+                        })();
+                    }();
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect: {
+        "use strict";
+        try {
+            (function() {
+                for (;;)
+                    throw "PASS";
+            })();
+        } catch (e) {
+            console.log(e);
+        }
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5552_1: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var log = console.log;
+        var a = f, b = log();
+        function f(...[ c = a = "PASS" ]) {}
+        f((a = "FAIL", b));
+        log(a);
+    }
+    expect: {
+        var log = console.log;
+        var a = f, b = log();
+        function f(...[ c = a = "PASS" ]) {}
+        f((a = "FAIL", b));
+        log(a);
+    }
+    expect_stdout: [
+        "",
+        "PASS",
+    ]
+    node_version: ">=6"
+}
+
+issue_5552_2: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var log = console.log;
+        var a = f;
+        function f(...{ [a = "PASS"]: b }) {}
+        f((a = "FAIL", 42));
+        log(a);
+    }
+    expect: {
+        var log = console.log;
+        var a = f;
+        function f(...{ [a = "PASS"]: b }) {}
+        f((a = "FAIL", 42));
+        log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5552_3: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = [ "FAIL", "PASS" ];
+        console.log(function(b, ...[ c = a.pop() ]) {
+            return b;
+        }(a.pop()));
+    }
+    expect: {
+        var a = [ "FAIL", "PASS" ];
+        console.log(function(b, ...[ c = a.pop() ]) {
+            return b;
+        }(a.pop()));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5552_4: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = [ "FAIL", "PASS" ];
+        console.log(function(b, ...{ [a.pop()]: c }) {
+            return b;
+        }(a.pop()));
+    }
+    expect: {
+        var a = [ "FAIL", "PASS" ];
+        console.log(function(b, ...{ [a.pop()]: c }) {
+            return b;
+        }(a.pop()));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5705: {
+    options = {
+        reduce_vars: true,
+        rests: true,
+        unused: true,
+    }
+    input: {
+        (function(...a) {
+            var b = { ...a };
+        })(console.log("PASS"));
+    }
+    expect: {
+        (function() {})(console.log("PASS"));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=8.3.0"
+}

test/compress/sandbox.js

@@ -125,6 +125,7 @@ log_nested: {
 
 timers: {
     options = {
+        evaluate: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -132,26 +133,22 @@ timers: {
     input: {
         var count = 0, interval = 1000, duration = 3210;
         var timer = setInterval(function() {
-            console.log(++count);
+            if (!count++) setTimeout(function() {
+                clearInterval(timer);
+                console.log(count <= 4 ? "PASS" : "FAIL");
+            }, duration);
         }, interval);
-        setTimeout(function() {
-            clearInterval(timer);
-        }, duration);
     }
     expect: {
         var count = 0;
         var timer = setInterval(function() {
-            console.log(++count);
+            if (!count++) setTimeout(function() {
+                clearInterval(timer);
+                console.log(count <= 4 ? "PASS" : "FAIL");
+            }, 3210);
         }, 1000);
-        setTimeout(function() {
-            clearInterval(timer);
-        }, 3210);
     }
-    expect_stdout: [
-        "1",
-        "2",
-        "3",
-    ]
+    expect_stdout: "PASS"
     node_version: ">=0.12"
 }
 

test/compress/side_effects.js

@@ -318,6 +318,32 @@ unsafe_string_replace: {
     expect_stdout: "PASS"
 }
 
+unsafe_Object_call: {
+    options = {
+        side_effects: true,
+        unsafe: true,
+    }
+    input: {
+        var o = {
+            f: function(a) {
+                console.log(a ? this.p : "FAIL 1");
+            },
+            p: "FAIL 2",
+        }, p = "PASS";
+        Object(o.f)(42);
+    }
+    expect: {
+        var o = {
+            f: function(a) {
+                console.log(a ? this.p : "FAIL 1");
+            },
+            p: "FAIL 2",
+        }, p = "PASS";
+        (0, o.f)(42);
+    }
+    expect_stdout: "PASS"
+}
+
 drop_value: {
     options = {
         side_effects: true,
@@ -698,3 +724,246 @@ retain_instanceof: {
     }
     expect_stdout: "PASS"
 }
+
+drop_access: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        var o = {};
+        o.p;
+        try {
+            (function() {
+                o.q;
+            })();
+            console.log("PASS");
+        } catch (e) {
+            console.log("FAIL");
+        }
+    }
+    expect: {
+        var o = {};
+        o.p;
+        try {
+            console.log("PASS");
+        } catch (e) {
+            console.log("FAIL");
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+keep_access: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        var o = {};
+        o.p;
+        o = null;
+        try {
+            (function() {
+                o.q;
+            })();
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        var o = {};
+        o.p;
+        o = null;
+        try {
+            (function() {
+                o.q;
+            })();
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+keep_access_after_call: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        var o = {};
+        o.p;
+        o.q;
+        f();
+        try {
+            o.r;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+        function f() {
+            o = null;
+        }
+    }
+    expect: {
+        var o = {};
+        o.p;
+        f();
+        try {
+            o.r;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+        function f() {
+            o = null;
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5860_drop_1: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        var a = {};
+        a.p;
+        var a;
+        a.q;
+        console.log("PASS");
+    }
+    expect: {
+        var a = {};
+        a.p;
+        var a;
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5860_drop_2: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        a = {};
+        a.p;
+        var a;
+        a.q;
+        console.log("PASS");
+    }
+    expect: {
+        a = {};
+        a.p;
+        var a;
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5860_keep_1: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        var a = {};
+        a.p;
+        a.q;
+        var a = null;
+        try {
+            a.r;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        var a = {};
+        a.p;
+        var a = null;
+        try {
+            a.r;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5860_keep_2: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        a = {};
+        a.p;
+        a.q;
+        var a = null;
+        try {
+            a.r;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        a = {};
+        a.p;
+        var a = null;
+        try {
+            a.r;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5860_keep_3: {
+    options = {
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        var a = {};
+        a.p;
+        a.q;
+        a = null;
+        try {
+            a.r;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        var a = {};
+        a.p;
+        a = null;
+        try {
+            a.r;
+            console.log("FAIL");
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+}

test/compress/spreads.js

@@ -1,15 +1,24 @@
+decimal: {
+    input: {
+        console.log({... 0.42});
+    }
+    expect_exact: "console.log({....42});"
+    expect_stdout: "{}"
+    node_version: ">=8.3.0"
+}
+
 collapse_vars_1: {
     options = {
         collapse_vars: true,
     }
     input: {
         var a;
-        [ ...a = "PASS", "PASS"].slice();
+        [ ...a = "PASS", "PASS" ].slice();
         console.log(a);
     }
     expect: {
         var a;
-        [ ...a = "PASS", "PASS"].slice();
+        [ ...a = "PASS", "PASS" ].slice();
         console.log(a);
     }
     expect_stdout: "PASS"
@@ -24,7 +33,7 @@ collapse_vars_2: {
         var a = "FAIL";
         try {
             a = "PASS";
-            [ ...42, "PASS"].slice();
+            [ ...42, "PASS" ].slice();
         } catch (e) {
             console.log(a);
         }
@@ -33,7 +42,7 @@ collapse_vars_2: {
         var a = "FAIL";
         try {
             a = "PASS";
-            [ ...42, "PASS"].slice();
+            [ ...42, "PASS" ].slice();
         } catch (e) {
             console.log(a);
         }
@@ -49,7 +58,7 @@ collapse_vars_3: {
     input: {
         var a = "FAIL";
         try {
-            [ ...(a = "PASS", 42), "PASS"].slice();
+            [ ...(a = "PASS", 42), "PASS" ].slice();
         } catch (e) {
             console.log(a);
         }
@@ -57,7 +66,7 @@ collapse_vars_3: {
     expect: {
         var a = "FAIL";
         try {
-            [ ...(a = "PASS", 42), "PASS"].slice();
+            [ ...(a = "PASS", 42), "PASS" ].slice();
         } catch (e) {
             console.log(a);
         }
@@ -1194,3 +1203,74 @@ issue_5382: {
     expect_stdout: "PASS"
     node_version: ">=8.3.0"
 }
+
+issue_5602: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        evaluate: true,
+        if_return: true,
+        inline: true,
+        passes: 2,
+        sequences: true,
+        spreads: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            try {
+                var b = function(c) {
+                    if (c)
+                        return FAIL;
+                    var d = 42;
+                }(...[ null, A = 0 ]);
+            } catch (e) {
+                b();
+            }
+        })();
+        console.log(A);
+    }
+    expect: {
+        (function() {
+            try {
+                var b = void (A = 0);
+            } catch (e) {
+                b();
+            }
+        })(),
+        console.log(A);
+    }
+    expect_stdout: "0"
+    expect_warnings: [
+        "INFO: Dropping unused variable d [test/compress/spreads.js:6,24]",
+        "INFO: Collapsing c [test/compress/spreads.js:4,24]",
+        "INFO: Dropping unused variable c [test/compress/spreads.js:3,33]",
+        "INFO: pass 0: last_count: Infinity, count: 27",
+        "WARN: Condition always false [test/compress/spreads.js:4,20]",
+        "INFO: Collapsing null [test/compress/spreads.js:7,23]",
+        "INFO: Collapsing 0 [test/compress/spreads.js:3,24]",
+        "INFO: pass 1: last_count: 27, count: 22",
+    ]
+    node_version: ">=6"
+}
+
+issue_5850: {
+    options = {
+        evaluate: true,
+        join_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = [ ..."FAIL" ];
+        a[0] = "P";
+        a[2] = a[3] = "S";
+        console.log(a.join(""));
+    }
+    expect: {
+        var a = [ ..."FAIL" ];
+        a[0] = "P";
+        a[2] = a[3] = "S";
+        console.log(a.join(""));
+    }
+    node_version: ">=6"
+}

test/compress/switches.js

@@ -1608,3 +1608,83 @@ issue_5012: {
     }
     expect_stdout: "PASS"
 }
+
+issue_5543_1: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        var a;
+        switch (a) {
+          default:
+            switch (42) {
+              case a:
+              case console.log("PASS"):
+            }
+            break;
+          case null:
+            switch (false) {
+              case a:
+              case console.log("FAIL"):
+            }
+        }
+    }
+    expect: {
+        var a;
+        switch (a) {
+          default:
+            switch (42) {
+              case a:
+              case console.log("PASS"):
+            }
+            break;
+          case null:
+            switch (false) {
+              case a:
+              case console.log("FAIL"):
+            }
+        }
+    }
+    expect_stdout: "PASS"
+}
+
+issue_5543_2: {
+    options = {
+        dead_code: true,
+        switches: true,
+    }
+    input: {
+        var a;
+        switch (a) {
+          default:
+            switch (42) {
+              case a:
+              case console.log("PASS"):
+            }
+            break;
+          case null:
+            switch (42) {
+              case a:
+              case console.log("FAIL"):
+            }
+        }
+    }
+    expect: {
+        var a;
+        switch (a) {
+          default:
+            switch (42) {
+              case a:
+              case console.log("PASS"):
+            }
+            break;
+          case null:
+            switch (42) {
+              case a:
+              case console.log("FAIL"):
+            }
+        }
+    }
+    expect_stdout: "PASS"
+}

test/compress/transform.js

@@ -127,7 +127,7 @@ if_return: {
                 if (w) {
                     if (y) return;
                 } else if (z) return;
-                return x == y || (x && w(), y && z()), !0;
+                return x != y && (x && w(), y) && z(), !0;
             }
         }
     }

test/compress/varify.js

@@ -194,6 +194,43 @@ scope_adjustment_let: {
     node_version: ">=4"
 }
 
+escaped_const: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        const log = console.log;
+        log("PASS");
+    }
+    expect: {
+        var log = console.log;
+        log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+escaped_let: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        let log = console.log;
+        log("PASS");
+    }
+    expect: {
+        "use strict";
+        var log = console.log;
+        log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
 issue_4191_const: {
     options = {
         functions: true,
@@ -292,6 +329,42 @@ forin_const_2: {
     node_version: ">=6"
 }
 
+forin_const_3: {
+    options = {
+        module: true,
+        reduce_vars: true,
+        toplevel: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        const o = {
+            p: 42,
+            q: "PASS",
+        };
+        for (const k in o)
+            (function f() {
+                console.log(k, o[k]);
+            })();
+    }
+    expect: {
+        "use strict";
+        let o = {
+            p: 42,
+            q: "PASS",
+        };
+        for (let k in o)
+            (function f() {
+                console.log(k, o[k]);
+            })();
+    }
+    expect_stdout: [
+        "p 42",
+        "q PASS",
+    ]
+    node_version: ">=4"
+}
+
 forin_let_1: {
     options = {
         join_vars: true,
@@ -613,3 +686,197 @@ issue_4954: {
     ]
     node_version: ">=4"
 }
+
+issue_5516: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        console.log(typeof function() {
+            {
+                let a;
+            }
+            {
+                const a = function() {};
+                return a;
+            }
+        }());
+    }
+    expect: {
+        "use strict";
+        console.log(typeof function() {
+            {
+                const a = function() {};
+                return a;
+            }
+        }());
+    }
+    expect_stdout: "function"
+    node_version: ">=4"
+}
+
+issue_5697_1: {
+    options = {
+        if_return: true,
+        inline: true,
+        reduce_vars: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        console.log(function() {
+            f();
+            return typeof a;
+            function f() {
+                (function() {
+                    for (var k in { foo: 42 }) {
+                        const a = k;
+                        console.log(a);
+                    }
+                })();
+            }
+        }());
+    }
+    expect: {
+        console.log(function() {
+            (function() {
+                for (var k in { foo: 42 }) {
+                    var a = k;
+                    console.log(a);
+                }
+            })();
+            return typeof a;
+        }());
+    }
+    expect_stdout: [
+        "foo",
+        "undefined",
+    ]
+}
+
+issue_5697_2: {
+    options = {
+        if_return: true,
+        inline: true,
+        reduce_vars: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        console.log(function() {
+            f();
+            return typeof a;
+            function f() {
+                (function() {
+                    for (var k in { foo: 42 }) {
+                        let a = k;
+                        console.log(a);
+                    }
+                })();
+            }
+        }());
+    }
+    expect: {
+        "use strict";
+        console.log(function() {
+            (function() {
+                for (var k in { foo: 42 }) {
+                    var a = k;
+                    console.log(a);
+                }
+            })();
+            return typeof a;
+        }());
+    }
+    expect_stdout: [
+        "foo",
+        "undefined",
+    ]
+    node_version: ">=4"
+}
+
+issue_5697_3: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        console.log(function() {
+            f();
+            return typeof a;
+            function f() {
+                (function() {
+                    for (var k in { foo: 42 }) {
+                        const a = k;
+                        console.log(a);
+                    }
+                })();
+            }
+        }());
+    }
+    expect: {
+        console.log(function() {
+            (function() {
+                for (var k in { foo: 42 }) {
+                    var a = k;
+                    console.log(a);
+                }
+            })();
+            return typeof a;
+        }());
+    }
+    expect_stdout: [
+        "foo",
+        "undefined",
+    ]
+}
+
+issue_5697_4: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+        varify: true,
+    }
+    input: {
+        "use strict";
+        console.log(function() {
+            f();
+            return typeof a;
+            function f() {
+                (function() {
+                    for (var k in { foo: 42 }) {
+                        let a = k;
+                        console.log(a);
+                    }
+                })();
+            }
+        }());
+    }
+    expect: {
+        "use strict";
+        console.log(function() {
+            (function() {
+                for (var k in { foo: 42 }) {
+                    var a = k;
+                    console.log(a);
+                }
+            })();
+            return typeof a;
+        }());
+    }
+    expect_stdout: [
+        "foo",
+        "undefined",
+    ]
+    node_version: ">=4"
+}

test/compress/yields.js

@@ -896,7 +896,7 @@ dont_inline_nested: {
     node_version: ">=4"
 }
 
-drop_body: {
+drop_body_1: {
     options = {
         side_effects: true,
         yields: true,
@@ -907,7 +907,28 @@ drop_body: {
         })([ console.log("baz") ]);
     }
     expect: {
-        [ [ , [].e = console.log("foo") ] ] = [ [ console.log("baz") ] ];
+        void ([ [ , [][0] = console.log("foo") ] ] = [ [ console.log("baz") ] ]);
+    }
+    expect_stdout: [
+        "baz",
+        "foo",
+    ]
+    node_version: ">=6"
+}
+
+drop_body_2: {
+    options = {
+        passes: 2,
+        side_effects: true,
+        yields: true,
+    }
+    input: {
+        (function*([ , a = console.log("foo") ]) {
+            console.log("bar");
+        })([ console.log("baz") ]);
+    }
+    expect: {
+        [ [ , [][0] = console.log("foo") ] ] = [ [ console.log("baz") ] ];
     }
     expect_stdout: [
         "baz",
@@ -1183,6 +1204,35 @@ issue_4641_2: {
     node_version: ">=10"
 }
 
+issue_4641_3: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        console.log(typeof async function*() {
+            try {
+                return void "FAIL";
+            } finally {
+                console.log("PASS");
+            }
+        }().next().then);
+    }
+    expect: {
+        console.log(typeof async function*() {
+            try {
+                return void "FAIL";
+            } finally {
+                console.log("PASS");
+            }
+        }().next().then);
+    }
+    expect_stdout: [
+        "function",
+        "PASS",
+    ]
+    node_version: ">=10"
+}
+
 issue_4769_1: {
     options = {
         side_effects: true,
@@ -1336,7 +1386,7 @@ issue_5076_1: {
     expect: {
         var a;
         console.log("PASS"),
-        a = 42["a"];
+        a = 42..a;
     }
     expect_stdout: "PASS"
     node_version: ">=6"
@@ -1467,6 +1517,80 @@ issue_5385_2: {
     node_version: ">=10"
 }
 
+issue_5385_3: {
+    options = {
+        inline: true,
+    }
+    input: {
+        (async function*() {
+            return function() {
+                try {
+                    throw console.log("foo");
+                } catch (e) {
+                    return console.log("bar");
+                }
+            }();
+        })().next();
+        console.log("moo");
+    }
+    expect: {
+        (async function*() {
+            try {
+                throw console.log("foo");
+            } catch (e) {
+                return console.log("bar");
+            }
+            return void 0;
+        })().next();
+        console.log("moo");
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+        "moo",
+    ]
+    node_version: ">=10"
+}
+
+issue_5385_4: {
+    options = {
+        awaits: true,
+        inline: true,
+    }
+    input: {
+        (async function*() {
+            return async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            resolve(console.log("FAIL"));
+                        },
+                    };
+                } finally {
+                    return "PASS";
+                }
+            }();
+        })().next().then(o => console.log(o.value, o.done));
+    }
+    expect: {
+        (async function*() {
+            return async function() {
+                try {
+                    return {
+                        then(resolve) {
+                            resolve(console.log("FAIL"));
+                        },
+                    };
+                } finally {
+                    return "PASS";
+                }
+            }();
+        })().next().then(o => console.log(o.value, o.done));
+    }
+    expect_stdout: "PASS true"
+    node_version: ">=10"
+}
+
 issue_5425: {
     options = {
         assignments: true,
@@ -1562,3 +1686,564 @@ issue_5506: {
     expect_stdout: "PASS"
     node_version: ">=4"
 }
+
+issue_5526: {
+    options = {
+        inline: true,
+        side_effects: true,
+    }
+    input: {
+        (async function*() {
+            try {
+                return function() {
+                    while (console.log("foo"));
+                }();
+            } finally {
+                console.log("bar");
+            }
+        })().next();
+        console.log("baz");
+    }
+    expect: {
+        (async function*() {
+            try {
+                while (console.log("foo"));
+                return void 0;
+            } finally {
+                console.log("bar");
+            }
+        })().next();
+        console.log("baz");
+    }
+    expect_stdout: [
+        "foo",
+        "baz",
+        "bar",
+    ]
+    node_version: ">=10"
+}
+
+issue_5576: {
+    options = {
+        inline: true,
+    }
+    input: {
+        (async function*() {
+            try {
+                (function() {
+                    while (console.log("foo"));
+                })();
+            } finally {
+                console.log("bar");
+            }
+        })().next();
+        console.log("baz");
+    }
+    expect: {
+        (async function*() {
+            try {
+                while (console.log("foo"));
+            } finally {
+                console.log("bar");
+            }
+        })().next();
+        console.log("baz");
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+        "baz",
+    ]
+    node_version: ">=10"
+}
+
+issue_5663: {
+    options = {
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var [ , a ] = function*() {
+            console.log("foo");
+            yield console.log("bar");
+            console.log("baz");
+            yield console.log("moo");
+            console.log("moz");
+            yield FAIL;
+        }();
+    }
+    expect: {
+        var [ , , ] = function*() {
+            console.log("foo");
+            yield console.log("bar");
+            console.log("baz");
+            yield console.log("moo");
+            console.log("moz");
+            yield FAIL;
+        }();
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+        "baz",
+        "moo",
+    ]
+    node_version: ">=6"
+}
+
+issue_5679_1: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        var a = "FAIL";
+        async function* f(b) {
+            try {
+                if (b)
+                    return;
+                else
+                    return;
+            } finally {
+                a = "PASS";
+            }
+        }
+        f().next();
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        async function* f(b) {
+            try {
+                b;
+                return;
+            } finally {
+                a = "PASS";
+            }
+        }
+        f().next();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}
+
+issue_5679_2: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        var a = "FAIL";
+        async function* f(b) {
+            try {
+                if (b)
+                    return undefined;
+                else
+                    return;
+            } finally {
+                a = "PASS";
+            }
+        }
+        f().next();
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        async function* f(b) {
+            try {
+                if (b)
+                    return void 0;
+                return;
+            } finally {
+                a = "PASS";
+            }
+        }
+        f().next();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}
+
+issue_5679_3: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        var a = "FAIL";
+        async function* f(b) {
+            try {
+                if (b)
+                    return;
+                else
+                    return undefined;
+            } finally {
+                a = "PASS";
+            }
+        }
+        f(42).next();
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        async function* f(b) {
+            try {
+                if (b)
+                    return;
+                return void 0;
+            } finally {
+                a = "PASS";
+            }
+        }
+        f(42).next();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}
+
+issue_5679_4: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        var a = "PASS";
+        async function* f(b) {
+            try {
+                if (b)
+                    return undefined;
+                else
+                    return undefined;
+            } finally {
+                a = "FAIL";
+            }
+        }
+        f(null).next();
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        async function* f(b) {
+            try {
+                return b, void 0;
+            } finally {
+                a = "FAIL";
+            }
+        }
+        f(null).next();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}
+
+issue_5679_5: {
+    options = {
+        conditionals: true,
+        if_return: true,
+    }
+    input: {
+        var a = "FAIL";
+        async function* f(b) {
+            try {
+                if (b)
+                    return console;
+                else
+                    return;
+            } finally {
+                a = "PASS";
+            }
+        }
+        f().next();
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        async function* f(b) {
+            try {
+                if (b)
+                    return console;
+                return;
+            } finally {
+                a = "PASS";
+            }
+        }
+        f().next();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}
+
+issue_5679_6: {
+    options = {
+        conditionals: true,
+        if_return: true,
+    }
+    input: {
+        var a = "PASS";
+        async function* f(b) {
+            try {
+                if (b)
+                    return;
+                else
+                    return console;
+            } finally {
+                a = "FAIL";
+            }
+        }
+        f().next();
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        async function* f(b) {
+            try {
+                if (!b)
+                    return console;
+            } finally {
+                a = "FAIL";
+            }
+        }
+        f().next();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}
+
+issue_5684: {
+    options = {
+        conditionals: true,
+        if_return: true,
+    }
+    input: {
+        (async function*() {
+            switch (42) {
+              default:
+                if (console.log("PASS"))
+                    return;
+                return null;
+              case false:
+            }
+        })().next();
+    }
+    expect: {
+        (async function*() {
+            switch (42) {
+              default:
+                return console.log("PASS") ? void 0 : null;
+              case false:
+            }
+        })().next();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}
+
+issue_5707_1: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+        yields: true,
+    }
+    input: {
+        var a, b;
+        function* f(c = (b = 42, console.log("PASS"))) {}
+        b = f();
+    }
+    expect: {
+        (function(c = console.log("PASS")) {})();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5707_2: {
+    options = {
+        hoist_props: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+        yields: true,
+    }
+    input: {
+        var a, b;
+        function* f(c = (b = 42, console.log("PASS"))) {}
+        b = f();
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}
+
+issue_5710: {
+    options = {
+        conditionals: true,
+        if_return: true,
+    }
+    input: {
+        (async function*() {
+            try {
+                switch (42) {
+                  case 42:
+                    {
+                        if (console.log("PASS"))
+                            return;
+                        return null;
+                    }
+                    break;
+                }
+            } finally {}
+        })().next();
+    }
+    expect: {
+        (async function*() {
+            try {
+                switch (42) {
+                  case 42:
+                    if (console.log("PASS"))
+                        return;
+                    return null;
+                    break;
+                }
+            } finally {}
+        })().next();
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}
+
+issue_5749_1: {
+    options = {
+        collapse_vars: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+        yields: true,
+    }
+    input: {
+        var a;
+        function* f() {}
+        a = f(new function() {
+            var b = a |= 0, c = a += console.log("PASS");
+        }());
+    }
+    expect: {
+        (function() {})(function() {
+            console.log("PASS");
+        }());
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5749_2: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+        yields: true,
+    }
+    input: {
+        var a;
+        function* f() {}
+        a = f(new function() {
+            var b = a |= 0, c = a += console.log("PASS");
+        }());
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+issue_5754: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        async function* f(a, b) {
+            try {
+                if (a)
+                    return void 0;
+            } finally {
+                console.log(b);
+            }
+        }
+        f(42, "foo").next();
+        f(null, "bar").next();
+        console.log("baz");
+    }
+    expect: {
+        async function* f(a, b) {
+            try {
+                if (a)
+                    return void 0;
+            } finally {
+                console.log(b);
+            }
+        }
+        f(42, "foo").next();
+        f(null, "bar").next();
+        console.log("baz");
+    }
+    expect_stdout: [
+        "bar",
+        "baz",
+        "foo",
+    ]
+    node_version: ">=10"
+}
+
+issue_5842: {
+    options = {
+        inline: true,
+    }
+    input: {
+        var a = "FAIL";
+        (async function*() {
+            (function() {
+                try {
+                    try {
+                        return console;
+                    } finally {
+                        a = "PASS";
+                    }
+                } catch (e) {}
+                FAIL;
+            })();
+        })().next();
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        (async function*() {
+            (function() {
+                try {
+                    try {
+                        return console;
+                    } finally {
+                        a = "PASS";
+                    }
+                } catch (e) {}
+                FAIL;
+            })();
+        })().next();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=10"
+}

test/input/issue-3040/expect.js

@@ -38,4 +38,4 @@ var _require = require("bar"), foo = _require.foo;
 var _require2 = require("world"), hello = _require2.hello;
 
 foo.x.apply(foo, _toConsumableArray(foo.y(hello.z)));
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,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
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,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

test/input/issue-3294/output.js

@@ -1,2 +1,2 @@
 console.log(3);
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUEwQkEsUUFBUUMsSUFBSSJ9
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUEwQkEsUUFBUUMsSUFBSSxDQUFHIn0=

test/input/issue-505/output.js

@@ -2,4 +2,4 @@ function test(a){
 "aaaaaaaaaaaaaaaa";
 a(err,data),a(err,
 data)}
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsidGVzdCIsImNhbGxiYWNrIiwiZXJyIiwiZGF0YSJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0E7SEFBS0M7QUFFVkE7aEJBQVNDLElBQUtDLE1BQ2RGLEVBQVNDLElBQUtDIn0=
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsidGVzdCIsImNhbGxiYWNrIiwiZXJyIiwiZGF0YSJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0E7SEFBS0MsR0FDVjtBQUNBQTtoQkFBU0MsSUFBS0MsSUFBSSxFQUNsQkYsRUFBU0MsSUFBS0MsSUFBSSxDQUN0QiJ9

test/input/issue-520/output.js

@@ -1,2 +1,2 @@
 console.log(3);
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUEwQkEsUUFBUUMsSUFBSSJ9
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUEwQkEsUUFBUUMsSUFBSSxDQUFHIn0=

test/input/reduce/unsafe_math.reduced.js

@@ -1,16 +1,10 @@
 // (beautified)
-var b = 0;
-
 var expr2 = (0 - 1 - .1 - .1).toString();
 
-for (var key2 in expr2) {
-    --b;
-}
-
-console.log(b);
-// output: -19
+console.log(expr2);
+// output: -1.2000000000000002
 // 
-// minify: -4
+// minify: -1.2
 // 
 // options: {
 //   "compress": {

test/jetstream.js

@@ -14,7 +14,7 @@ if (typeof phantom == "undefined") {
         args.splice(debug, 1);
         debug = true;
     }
-    if (!args.length) args.push("-mcb", "beautify=false,webkit");
+    if (!args.length) args.push("-mcO", "webkit");
     args.unshift("bin/uglifyjs");
     args.push("--validate", "--timings");
     var child_process = require("child_process");
@@ -62,7 +62,11 @@ if (typeof phantom == "undefined") {
         var cmd = process.platform == "win32" ? "npm.cmd" : "npm";
 
         function npm(args, done) {
-            child_process.spawn(cmd, args, { stdio: [ "ignore", 1, 2 ] }).on("exit", done);
+            args.push("--loglevel=error");
+            child_process.spawn(cmd, args, {
+                shell: true,
+                stdio: [ "ignore", 1, 2 ],
+            }).on("exit", done);
         }
 
         (function install() {
@@ -72,9 +76,12 @@ if (typeof phantom == "undefined") {
                 "is-my-json-valid@2.20.5",
                 "phantomjs-prebuilt@2.1.14",
                 "--no-audit",
+                "--no-fund",
                 "--no-optional",
                 "--no-save",
+                "--no-strict-ssl",
                 "--no-update-notifier",
+                "--production",
             ], function(code) {
                 if (code) {
                     console.log("npm install failed with code", code);

test/mocha.js

@@ -1,13 +1,14 @@
 var fs = require("fs");
 
 var config = {
-    limit: 10000,
     timeout: function(limit) {
-        this.limit = limit;
-    }
+        this.limit = limit + lag;
+    },
 };
+var lag = +process.env["UGLIFY_GITHUB_LAG"] || 0;
 var tasks = [];
 var titles = [];
+config.timeout(10000);
 describe = function(title, fn) {
     config = Object.create(config);
     titles.push(title);
@@ -21,10 +22,11 @@ it = function(title, fn) {
     fn.titles.push(title);
     tasks.push(fn);
 };
-
-fs.readdirSync("test/mocha").filter(function(file) {
-    return /\.js$/.test(file);
-}).forEach(function(file) {
+(function(arg) {
+    return arg ? [ arg ] : fs.readdirSync("test/mocha").filter(function(file) {
+        return /\.js$/.test(file);
+    });
+})(process.argv[2]).forEach(function(file) {
     require("./mocha/" + file);
 });
 
@@ -66,12 +68,13 @@ process.nextTick(function run() {
         if (task.length) {
             task.timeout = function(limit) {
                 clearTimeout(timer);
+                limit += lag;
                 task.limit = limit;
                 timer = setTimeout(function() {
                     raise(new Error("Timed out: exceeds " + limit + "ms"));
                 }, limit);
             };
-            task.timeout(task.limit);
+            task.timeout(task.limit - lag);
             process.on("uncaughtException", raise);
             task.call(task, done);
         } else {

test/mocha/cli.js

@@ -53,6 +53,23 @@ describe("bin/uglifyjs", function() {
             done();
         });
     });
+    it("Should work with --expression", function(done) {
+        exec([
+            uglifyjscmd,
+            "--expression",
+            "--compress",
+            "--mangle",
+        ].join(" "), function(err, stdout) {
+            if (err) throw err;
+            assert.strictEqual(stdout, "function(n){for(;n(););return 42}(A)\n");
+            done();
+        }).stdin.end([
+            "function(x) {",
+            "    while (x()) {}",
+            "    return 42;",
+            "}(A)",
+        ].join("\n"));
+    });
     it("Should work with --source-map names=true", function(done) {
         exec([
             uglifyjscmd,
@@ -69,7 +86,7 @@ describe("bin/uglifyjs", function() {
                 "    q: b",
                 "};",
                 "//# sourceMappingURL=data:application/json;charset=utf-8;base64,",
-            ].join("\n")
+            ].join("\n");
             assert.strictEqual(stdout.slice(0, expected.length), expected);
             var map = JSON.parse(to_ascii(stdout.slice(expected.length).trim()));
             assert.deepEqual(map.names, [ "obj", "p", "a", "q", "b" ]);
@@ -97,7 +114,7 @@ describe("bin/uglifyjs", function() {
                 "    q: b",
                 "};",
                 "//# sourceMappingURL=data:application/json;charset=utf-8;base64,",
-            ].join("\n")
+            ].join("\n");
             assert.strictEqual(stdout.slice(0, expected.length), expected);
             var map = JSON.parse(to_ascii(stdout.slice(expected.length).trim()));
             assert.deepEqual(map.names, []);
@@ -126,7 +143,7 @@ describe("bin/uglifyjs", function() {
             if (err) throw err;
             assert.strictEqual(stdout, [
                 "var bar=function(){function foo(bar){return bar}return foo}();",
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFJQSxJQUFNLFdBQ04sU0FBU0MsSUFBS0QsS0FDVixPQUFPQSxJQUdYLE9BQU9DLElBTEQifQ==",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFJQSxJQUFNLFdBQ04sU0FBU0MsSUFBS0QsS0FDVixPQUFPQSxHQUNYLENBRUEsT0FBT0MsR0FDVixFQUFFIn0=",
                 "",
             ].join("\n"));
             done();
@@ -189,7 +206,13 @@ describe("bin/uglifyjs", function() {
         }, 1000);
     });
     it("Should work with --keep-fargs (mangle only)", function(done) {
-        var command = uglifyjscmd + ' test/input/issue-1431/sample.js --keep-fargs -m';
+        var command = [
+            uglifyjscmd,
+            "test/input/issue-1431/sample.js",
+            "--keep-fargs",
+            "--mangle",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
             assert.strictEqual(stdout, "function f(x){return function(){function n(a){return a*a}return x(n)}}function g(op){return op(1)+op(2)}console.log(f(g)()==5);\n");
@@ -197,7 +220,14 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with --keep-fargs (mangle & compress)", function(done) {
-        var command = uglifyjscmd + ' test/input/issue-1431/sample.js --keep-fargs -m -c';
+        var command = [
+            uglifyjscmd,
+            "test/input/issue-1431/sample.js",
+            "--keep-fargs",
+            "--mangle",
+            "--no-module",
+            "--compress",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
             assert.strictEqual(stdout, "function f(x){return function(){return x(function(a){return a*a})}}function g(op){return op(1)+op(2)}console.log(5==f(g)());\n");
@@ -205,7 +235,12 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with keep_fargs under mangler options", function(done) {
-        var command = uglifyjscmd + ' test/input/issue-1431/sample.js -m keep_fargs=true';
+        var command = [
+            uglifyjscmd,
+            "test/input/issue-1431/sample.js",
+            "--mangle", "keep_fargs=true",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
             assert.strictEqual(stdout, "function f(x){return function(){function n(a){return a*a}return x(n)}}function g(op){return op(1)+op(2)}console.log(f(g)()==5);\n");
@@ -213,7 +248,12 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with --keep-fnames (mangle only)", function(done) {
-        var command = uglifyjscmd + ' test/input/issue-1431/sample.js --keep-fnames -m';
+        var command = [
+            uglifyjscmd,
+            "test/input/issue-1431/sample.js",
+            "--keep-fnames",
+            "--mangle",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
             assert.strictEqual(stdout, "function f(r){return function(){function n(n){return n*n}return r(n)}}function g(n){return n(1)+n(2)}console.log(f(g)()==5);\n");
@@ -221,7 +261,14 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with --keep-fnames (mangle & compress)", function(done) {
-        var command = uglifyjscmd + ' test/input/issue-1431/sample.js --keep-fnames -m -c';
+        var command = [
+            uglifyjscmd,
+            "test/input/issue-1431/sample.js",
+            "--keep-fnames",
+            "--mangle",
+            "--no-module",
+            "--compress",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
             assert.strictEqual(stdout, "function f(n){return function(){return n(function n(r){return r*r})}}function g(n){return n(1)+n(2)}console.log(5==f(g)());\n");
@@ -313,7 +360,7 @@ describe("bin/uglifyjs", function() {
             if (err) throw err;
             assert.strictEqual(stdout, [
                 "var bar=function(){function foo(bar){return bar}return foo}();",
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFJQSxJQUFNLFdBQ04sU0FBU0MsSUFBS0QsS0FDVixPQUFPQSxJQUdYLE9BQU9DLElBTEQifQ==",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMTMyMy9zYW1wbGUuanMiXSwibmFtZXMiOlsiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFJQSxJQUFNLFdBQ04sU0FBU0MsSUFBS0QsS0FDVixPQUFPQSxHQUNYLENBRUEsT0FBT0MsR0FDVixFQUFFIn0=",
                 "",
             ].join("\n"));
             var stderrLines = stderr.split("\n");
@@ -333,7 +380,7 @@ describe("bin/uglifyjs", function() {
             if (err) throw err;
             assert.strictEqual(stdout, [
                 "var Foo=function Foo(){console.log(1+2)};new Foo;var bar=function(){function foo(bar){return bar}return foo}();",
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIiwidGVzdC9pbnB1dC9pc3N1ZS0xMzIzL3NhbXBsZS5qcyJdLCJuYW1lcyI6WyJGb28iLCJjb25zb2xlIiwibG9nIiwiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFNQSxJQUFJLFNBQUVBLE1BQWNDLFFBQVFDLElBQUksRUFBRSxJQUFPLElBQUlGLElDQW5ELElBQUlHLElBQU0sV0FDTixTQUFTQyxJQUFLRCxLQUNWLE9BQU9BLElBR1gsT0FBT0MsSUFMRCJ9",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIiwidGVzdC9pbnB1dC9pc3N1ZS0xMzIzL3NhbXBsZS5qcyJdLCJuYW1lcyI6WyJGb28iLCJjb25zb2xlIiwibG9nIiwiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFNQSxJQUFJLFNBQUVBLE1BQWNDLFFBQVFDLElBQUksRUFBRSxDQUFDLENBQUUsRUFBSSxJQUFJRixJQ0FuRCxJQUFJRyxJQUFNLFdBQ04sU0FBU0MsSUFBS0QsS0FDVixPQUFPQSxHQUNYLENBRUEsT0FBT0MsR0FDVixFQUFFIn0=",
                 "",
             ].join("\n"));
             var stderrLines = stderr.split("\n");
@@ -540,7 +587,11 @@ 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",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -554,7 +605,11 @@ 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",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -568,7 +623,11 @@ 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",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -582,7 +641,11 @@ 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",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -596,7 +659,11 @@ 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",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -610,7 +677,11 @@ 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",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -624,7 +695,11 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should throw syntax error (var { eval })", function(done) {
-        var command = uglifyjscmd + " test/input/invalid/destructured_var.js";
+        var command = [
+            uglifyjscmd,
+            "test/input/invalid/destructured_var.js",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
@@ -774,7 +849,7 @@ describe("bin/uglifyjs", function() {
             if (err) throw err;
             assert.strictEqual(stdout, [
                 '"use strict";var foo=function foo(x){return"foo "+x};console.log(foo("bar"));',
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbImluZGV4LmpzIl0sIm5hbWVzIjpbImZvbyIsIngiLCJjb25zb2xlIiwibG9nIl0sIm1hcHBpbmdzIjoiYUFBQSxJQUFJQSxJQUFNLFNBQU5BLElBQU1DLEdBQUEsTUFBSyxPQUFTQSxHQUN4QkMsUUFBUUMsSUFBSUgsSUFBSSJ9",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbImluZGV4LmpzIl0sIm5hbWVzIjpbImZvbyIsIngiLCJjb25zb2xlIiwibG9nIl0sIm1hcHBpbmdzIjoiYUFBQSxJQUFJQSxJQUFNLFNBQU5BLElBQU1DLEdBQUEsTUFBSyxPQUFTQSxDQUFkLEVBQ1ZDLFFBQVFDLElBQUlILElBQUksS0FBSixDQUFaIn0=",
                 ""
             ].join("\n"));
             done();
@@ -790,14 +865,15 @@ describe("bin/uglifyjs", function() {
         var command = [
             uglifyjscmd,
             "test/input/issue-2310/input.js",
-            "-c",
+            "--compress",
+            "--no-module",
             "--source-map", "url=inline",
         ].join(" ");
         exec(command, function(err, stdout, stderr) {
             if (err) throw err;
             assert.strictEqual(stdout, [
                 'function foo(){return function(){console.log("PASS")}}foo()();',
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMjMxMC9pbnB1dC5qcyJdLCJuYW1lcyI6WyJmb28iLCJjb25zb2xlIiwibG9nIiwiZiJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0EsTUFDTCxPQUFPLFdBQ0hDLFFBQVFDLElBQUksU0FLUkYsS0FDUkcifQ==",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInRlc3QvaW5wdXQvaXNzdWUtMjMxMC9pbnB1dC5qcyJdLCJuYW1lcyI6WyJmb28iLCJjb25zb2xlIiwibG9nIl0sIm1hcHBpbmdzIjoiQUFBQSxTQUFTQSxNQUNMLE9BQU8sV0FDSEMsUUFBUUMsSUFBSSxNQUFNLENBQ3RCLENBQ0osQ0FHWUYsSUFBSSxFQUNWIn0=",
                 ""
             ].join("\n"));
             done();
@@ -823,7 +899,12 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with --mangle reserved=[]", function(done) {
-        var command = uglifyjscmd + " test/input/issue-505/input.js -m reserved=[callback]";
+        var command = [
+            uglifyjscmd,
+            "test/input/issue-505/input.js",
+            "--mangle", "reserved=[callback]",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
             assert.strictEqual(stdout, 'function test(callback){"aaaaaaaaaaaaaaaa";callback(err,data);callback(err,data)}\n');
@@ -831,7 +912,12 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with --mangle reserved=false", function(done) {
-        var command = uglifyjscmd + " test/input/issue-505/input.js -m reserved=false";
+        var command = [
+            uglifyjscmd,
+            "test/input/issue-505/input.js",
+            "--mangle", "reserved=false",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
             assert.strictEqual(stdout, 'function test(a){"aaaaaaaaaaaaaaaa";a(err,data);a(err,data)}\n');
@@ -848,7 +934,12 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with mangle.properties.regex from --config-file", function(done) {
-        var command = uglifyjscmd + " test/input/issue-3315/input.js --config-file test/input/issue-3315/config.json";
+        var command = [
+            uglifyjscmd,
+            "test/input/issue-3315/input.js",
+            "--config-file", "test/input/issue-3315/config.json",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
             assert.strictEqual(stdout, 'function f(){"aaaaaaaaaa";var a={prop:1,t:2};return a.prop+a.t}\n');
@@ -865,7 +956,12 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with explicit --rename", function(done) {
-        var command = uglifyjscmd + " test/input/rename/input.js --rename";
+        var command = [
+            uglifyjscmd,
+            "test/input/rename/input.js",
+            "--no-module",
+            "--rename",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             if (err) throw err;
             assert.strictEqual(stdout, "function f(a){return b(a);function b(c){return c+c}}\n");
@@ -873,7 +969,14 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with explicit --no-rename", function(done) {
-        var command = uglifyjscmd + " test/input/rename/input.js -mc passes=2 --no-rename";
+        var command = [
+            uglifyjscmd,
+            "test/input/rename/input.js",
+            "--compress", "passes=2",
+            "--mangle",
+            "--no-module",
+            "--no-rename",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             if (err) throw err;
             assert.strictEqual(stdout, "function f(n){return function(n){return n+n}(n)}\n");
@@ -881,7 +984,13 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with implicit --rename", function(done) {
-        var command = uglifyjscmd + " test/input/rename/input.js -mc passes=2";
+        var command = [
+            uglifyjscmd,
+            "test/input/rename/input.js",
+            "--compress", "passes=2",
+            "--mangle",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             if (err) throw err;
             assert.strictEqual(stdout, "function f(n){return n+n}\n");
@@ -889,7 +998,12 @@ describe("bin/uglifyjs", function() {
         });
     });
     it("Should work with implicit --no-rename", function(done) {
-        var command = uglifyjscmd + " test/input/rename/input.js -c passes=2";
+        var command = [
+            uglifyjscmd,
+            "test/input/rename/input.js",
+            "--compress", "passes=2",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout, stderr) {
             if (err) throw err;
             assert.strictEqual(stdout, "function f(x){return function(x){return x+x}(x)}\n");
@@ -954,12 +1068,7 @@ describe("bin/uglifyjs", function() {
         ]).join("\n");
         exec(uglifyjscmd + " -mc", function(err, stdout) {
             if (err) throw err;
-            assert.strictEqual(stdout, [
-                "console.log(function(){",
-                "var p={p:25},n={p:121},o={p:1024};",
-                "return p.p+n.p+o.p",
-                "}());\n",
-            ].join(""));
+            assert.strictEqual(stdout, "console.log(function(){var p={p:25},n={p:121},o={p:1024};return p.p+n.p+o.p}());\n");
             assert.strictEqual(run_code(stdout), run_code(code));
             done();
         }).stdin.end(code);

test/mocha/comments.js

@@ -400,7 +400,7 @@ describe("comments", function() {
             assert.strictEqual(ast.print_to_string({comments: "all"}), "/*!test1*/\n/*test2*/\n//!test3\n//test4\n//test5\n//!test6\n//test7\n//!test8");
         });
 
-        it("Should be able to filter commments with the 'some' option", function() {
+        it("Should be able to filter comments with the 'some' option", function() {
             var ast = UglifyJS.parse("// foo\n/*@preserve*/\n// bar\n/*@license*/\n//@license with the wrong comment type\n/*@cc_on something*/");
             assert.strictEqual(ast.print_to_string({comments: "some"}), "/*@preserve*/\n/*@license*/\n/*@cc_on something*/");
         });
@@ -476,7 +476,9 @@ describe("comments", function() {
             for (var i = 1; i <= 5000; ++i) js += "// " + i + "\n";
             for (; i <= 10000; ++i) js += "/* " + i + " */ /**/";
             js += "x; }";
-            var result = UglifyJS.minify(js, { mangle: false });
+            var result = UglifyJS.minify(js, {
+                mangle: false,
+            });
             assert.strictEqual(result.code, "function lots_of_comments(x){return 7-x}");
         });
     });

test/mocha/directives.js

@@ -348,7 +348,7 @@ describe("Directives", function() {
                 '"use strict";doSomething("foo");'
             ],
             [
-                // Nothing gets optimised in the compressor because "use asm" is the first statement
+                // Nothing gets optimized in the compressor because "use asm" is the first statement
                 '"use asm";"use\\x20strict";1+1;',
                 '"use asm";"use\\x20strict";1+1;'
             ],
@@ -373,7 +373,9 @@ describe("Directives", function() {
                 'function f(){}'
             ],
         ].forEach(function(test) {
-            var result = UglifyJS.minify(test[0]);
+            var result = UglifyJS.minify(test[0], {
+                module: false,
+            });
             if (result.error) throw result.error;
             assert.strictEqual(result.code, test[1], test[0]);
         });

test/mocha/exports.js

@@ -1,3 +1,4 @@
+var acorn = require("acorn");
 var assert = require("assert");
 var UglifyJS = require("../node");
 
@@ -25,6 +26,7 @@ describe("export", function() {
             "export { * };",
             "export { * as A };",
             "export { 42 as A };",
+            "export { 'A' as B };",
             "export { A as B-C };",
             "export { default as A };",
         ].forEach(function(code) {
@@ -51,8 +53,11 @@ describe("export", function() {
     it("Should reject invalid `export ... from ...` statement syntax", function() {
         [
             "export from 'path';",
+            "export A from 'path';",
             "export * from `path`;",
+            "export 'A' from 'path';",
             "export A as B from 'path';",
+            "export 'A' as B from 'path';",
             "export default from 'path';",
             "export { A }, B from 'path';",
             "export * as A, B from 'path';",
@@ -68,4 +73,109 @@ describe("export", function() {
             }, code);
         });
     });
+    it("Should reject `export` statement not under top-level scope", function() {
+        [
+            "{ export {}; }",
+            "if (0) export var A;",
+            "function f() { export default 42; }",
+        ].forEach(function(code) {
+            assert.throws(function() {
+                UglifyJS.parse(code);
+            }, function(e) {
+                return e instanceof UglifyJS.JS_Parse_Error;
+            }, code);
+        });
+    });
+    it("Should compare `export` statements correctly", function() {
+        var stats = {
+            Declaration: [
+                "export let A;",
+                "export const A = 42;",
+                "export var { A, B: [] } = C;",
+                "export function A() { return B(A); }",
+                "export async function* A({}, ...[]) { return B(A); }",
+            ],
+            Default: [
+                "export default 42;",
+                "export default A => A(B);",
+                "export default class A extends B {}",
+                "export default (class A extends B {});",
+                "export default class A { static C = 42; }",
+                "export default class A extends B { static C = 42; }",
+            ],
+            Foreign: [
+                "export * from 'path';",
+                "export {} from 'path';",
+                "export * as A from 'path';",
+                "export { default } from 'path';",
+                "export { A, B as C } from 'path';",
+                "export { A, default as C } from 'path';",
+            ],
+            References: [
+                "export {};",
+                "export { A };",
+                "export { A as B };",
+                "export { A, B as C };",
+                "export { A as default };",
+            ],
+        };
+        for (var k in stats) stats[k].forEach(function(c, i) {
+            var s = UglifyJS.parse(c);
+            assert.ok(s instanceof UglifyJS.AST_Toplevel, c);
+            assert.strictEqual(s.body.length, 1, c);
+            assert.strictEqual(s.body[0].TYPE, "Export" + k, c);
+            for (var l in stats) stats[l].forEach(function(d, j) {
+                var t = UglifyJS.parse(d);
+                assert.ok(t instanceof UglifyJS.AST_Toplevel, d);
+                assert.strictEqual(t.body.length, 1, d);
+                assert.strictEqual(t.body[0].TYPE, "Export" + l, d);
+                assert.strictEqual(s.equals(t), k === l && i === j, c + "\n" + d);
+            });
+        });
+    });
+    it("Should interoperate with ESTree correctly", function() {
+        [
+            "export var A = 42;",
+            "export default (class A {});",
+            "var A; export { A as '42' };",
+            "export { '42' } from 'path';",
+            "export * as '42' from 'path';",
+        ].forEach(function(code) {
+            var ast = UglifyJS.parse(code);
+            try {
+                var spidermonkey = ast.to_mozilla_ast();
+            } catch (ex) {
+                assert.fail("[to_mozilla_ast] " + ex.stack);
+            }
+            try {
+                var ast2 = UglifyJS.AST_Node.from_mozilla_ast(spidermonkey);
+            } catch (ex) {
+                assert.fail("[from_mozilla_ast] " + ex.stack);
+            }
+            assert.strictEqual(ast2.print_to_string(), ast.print_to_string(), [
+                "spidermonkey:",
+                ast.print_to_string(),
+                ast2.print_to_string(),
+            ].join("\n"));
+            try {
+                var acorn_est = acorn.parse(code, {
+                    ecmaVersion: "latest",
+                    locations: true,
+                    sourceType: "module",
+                });
+            } catch (ex) {
+                assert.fail("[acorn.parse] " + ex.stack);
+            }
+            try {
+                var ast3 = UglifyJS.AST_Node.from_mozilla_ast(acorn_est);
+            } catch (ex) {
+                assert.fail("[from_acorn] " + ex.stack);
+            }
+            assert.strictEqual(ast3.print_to_string(), ast.print_to_string(), [
+                "acorn:",
+                ast.print_to_string(),
+                ast3.print_to_string(),
+            ].join("\n"));
+        });
+    });
 });

test/mocha/glob.js

@@ -5,31 +5,44 @@ var path = require("path");
 describe("bin/uglifyjs with input file globs", function() {
     var uglifyjscmd = '"' + process.argv[0] + '" bin/uglifyjs';
     it("bin/uglifyjs with one input file extension glob.", function(done) {
-        var command = uglifyjscmd + ' "test/input/issue-1242/foo.*" -cm';
-
+        var command = [
+            uglifyjscmd,
+            '"test/input/issue-1242/foo.*"',
+            "--compress",
+            "--mangle",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
-
             assert.strictEqual(stdout, 'var print=console.log.bind(console);function foo(o){print("Foo:",2*o)}\n');
             done();
         });
     });
     it("bin/uglifyjs with one input file name glob.", function(done) {
-        var command = uglifyjscmd + ' "test/input/issue-1242/b*.es5" -cm';
-
+        var command = [
+            uglifyjscmd,
+            '"test/input/issue-1242/b*.es5"',
+            "--compress",
+            "--mangle",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
-
             assert.strictEqual(stdout, 'function bar(n){return 3*n}function baz(n){return n/2}\n');
             done();
         });
     });
     it("bin/uglifyjs with multiple input file globs.", function(done) {
-        var command = uglifyjscmd + ' "test/input/issue-1242/???.es5" "test/input/issue-1242/*.js" -mc toplevel,passes=3';
-
+        var command = [
+            uglifyjscmd,
+            '"test/input/issue-1242/???.es5"',
+            '"test/input/issue-1242/*.js"',
+            "--compress", "toplevel,passes=3",
+            "--mangle",
+            "--no-module",
+        ].join(" ");
         exec(command, function(err, stdout) {
             if (err) throw err;
-
             assert.strictEqual(stdout, 'var print=console.log.bind(console);print("qux",9,6),print("Foo:",22);\n');
             done();
         });

test/mocha/imports.js

@@ -1,3 +1,4 @@
+var acorn = require("acorn");
 var assert = require("assert");
 var UglifyJS = require("../node");
 
@@ -8,15 +9,25 @@ describe("import", function() {
             "import A;",
             "import {};",
             "import `path`;",
+            "{ import 'path'; }",
             "import from 'path';",
+            "if (0) import 'path';",
             "import * from 'path';",
+            "import 'A' from 'path';",
+            "import A-B from 'path';",
             "import A as B from 'path';",
             "import { A }, B from 'path';",
+            "import * as 'A' from 'path';",
+            "import * as A-B from 'path';",
             "import * as A, B from 'path';",
             "import * as A, {} from 'path';",
             "import { * as A } from 'path';",
+            "import { * as 'A' } from 'path';",
+            "import { * as A-B } from 'path';",
+            "function f() { import 'path'; }",
             "import { 42 as A } from 'path';",
             "import { A-B as C } from 'path';",
+            "import { 'A' as 'B' } from 'path';",
         ].forEach(function(code) {
             assert.throws(function() {
                 UglifyJS.parse(code);
@@ -25,4 +36,74 @@ describe("import", function() {
             }, code);
         });
     });
+    it("Should compare `import` statements correctly", function() {
+        [
+            "import 'foo';",
+            "import 'path';",
+            "import A from 'path';",
+            "import { A } from 'path';",
+            "import * as A from 'path';",
+            "import A, { B } from 'path';",
+            "import A, * as B from 'path';",
+            "import { A as B } from 'path';",
+            "import A, { B, C as D } from 'path';",
+        ].forEach(function(c, i, stats) {
+            var s = UglifyJS.parse(c);
+            assert.ok(s instanceof UglifyJS.AST_Toplevel, c);
+            assert.strictEqual(s.body.length, 1, c);
+            assert.ok(s.body[0] instanceof UglifyJS.AST_Import, c);
+            stats.forEach(function(d, j) {
+                var t = UglifyJS.parse(d);
+                assert.ok(t instanceof UglifyJS.AST_Toplevel, d);
+                assert.strictEqual(t.body.length, 1, d);
+                assert.ok(t.body[0] instanceof UglifyJS.AST_Import, d);
+                assert.strictEqual(s.equals(t), i === j, c + "\n" + d);
+            });
+        });
+    });
+    it("Should interoperate with ESTree correctly", function() {
+        [
+            "import A from 'path';",
+            "import * as A from 'path';",
+            "import A, * as B from 'path';",
+            "import { '42' as A, B } from 'path';",
+            "import A, { '42' as B } from 'path';",
+        ].forEach(function(code) {
+            var ast = UglifyJS.parse(code);
+            try {
+                var spidermonkey = ast.to_mozilla_ast();
+            } catch (ex) {
+                assert.fail("[to_mozilla_ast] " + ex.stack);
+            }
+            try {
+                var ast2 = UglifyJS.AST_Node.from_mozilla_ast(spidermonkey);
+            } catch (ex) {
+                assert.fail("[from_mozilla_ast] " + ex.stack);
+            }
+            assert.strictEqual(ast2.print_to_string(), ast.print_to_string(), [
+                "spidermonkey:",
+                ast.print_to_string(),
+                ast2.print_to_string(),
+            ].join("\n"));
+            try {
+                var acorn_est = acorn.parse(code, {
+                    ecmaVersion: "latest",
+                    locations: true,
+                    sourceType: "module",
+                });
+            } catch (ex) {
+                assert.fail("[acorn.parse] " + ex.stack);
+            }
+            try {
+                var ast3 = UglifyJS.AST_Node.from_mozilla_ast(acorn_est);
+            } catch (ex) {
+                assert.fail("[from_acorn] " + ex.stack);
+            }
+            assert.strictEqual(ast3.print_to_string(), ast.print_to_string(), [
+                "acorn:",
+                ast.print_to_string(),
+                ast3.print_to_string(),
+            ].join("\n"));
+        });
+    });
 });

test/mocha/let.js

@@ -12,17 +12,16 @@ describe("let", function() {
         s += '}';
         var result = UglifyJS.minify(s, {
             compress: false,
-        }).code;
-
+        });
+        if (result.error) throw result.error;
         // Verify that select keywords and reserved keywords not produced
         [
             "do",
             "let",
             "var",
         ].forEach(function(name) {
-            assert.strictEqual(result.indexOf("var " + name + "="), -1);
+            assert.strictEqual(result.code.indexOf("var " + name + "="), -1);
         });
-
         // Verify that the variable names that appeared immediately before
         // and after the erroneously generated variable name still exist
         // to show the test generated enough symbols.
@@ -31,27 +30,29 @@ describe("let", function() {
             "eet", "fet",
             "rar", "oar",
         ].forEach(function(name) {
-            assert.notStrictEqual(result.indexOf("var " + name + "="), -1);
+            assert.notStrictEqual(result.code.indexOf("var " + name + "="), -1);
         });
     });
     it("Should quote mangled properties that are reserved keywords", function() {
         var s = '"rrrrrnnnnniiiiiaaaaa";';
         for (var i = 0; i < 18000; i++) {
-            s += "v.b" + i + ";";
+            s += "v.b" + i + "=v;";
         }
         var result = UglifyJS.minify(s, {
             compress: false,
             ie: true,
             mangle: {
-                properties: true,
-            }
-        }).code;
+                properties: {
+                    domprops: true,
+                },
+            },
+        });
+        if (result.error) throw result.error;
         [
             "in",
             "var",
         ].forEach(function(name) {
-            assert.notStrictEqual(result.indexOf(name), -1);
-            assert.notStrictEqual(result.indexOf('v["' + name + '"]'), -1);
+            assert.notStrictEqual(result.code.indexOf('v["' + name + '"]'), -1);
         });
     });
     it("Should parse `let` as name correctly", function() {

test/mocha/minify-file-map.js

@@ -6,8 +6,10 @@ describe("Input file as map", function() {
         var jsMap = {
             '/scripts/foo.js': 'var foo = {"x": 1, y: 2, \'z\': 3};'
         };
-        var result = UglifyJS.minify(jsMap, {sourceMap: true});
-
+        var result = UglifyJS.minify(jsMap, {
+            sourceMap: true,
+        });
+        if (result.error) throw result.error;
         var map = JSON.parse(result.map);
         assert.strictEqual(result.code, 'var foo={x:1,y:2,z:3};');
         assert.deepEqual(map.sources, ['/scripts/foo.js']);
@@ -26,8 +28,10 @@ describe("Input file as map", function() {
             'var foo = {"x": 1, y: 2, \'z\': 3};',
             'var bar = 15;'
         ];
-        var result = UglifyJS.minify(jsSeq, {sourceMap: true});
-
+        var result = UglifyJS.minify(jsSeq, {
+            sourceMap: true,
+        });
+        if (result.error) throw result.error;
         var map = JSON.parse(result.map);
         assert.strictEqual(result.code, 'var foo={x:1,y:2,z:3},bar=15;');
         assert.deepEqual(map.sources, ['0', '1']);
@@ -37,8 +41,12 @@ describe("Input file as map", function() {
         var jsMap = {
             '/scripts/foo.js': 'var foo = {"x": 1, y: 2, \'z\': 3};'
         };
-        var result = UglifyJS.minify(jsMap, {sourceMap: {includeSources: true}});
-
+        var result = UglifyJS.minify(jsMap, {
+            sourceMap: {
+                includeSources: true,
+            },
+        });
+        if (result.error) throw result.error;
         var map = JSON.parse(result.map);
         assert.strictEqual(result.code, 'var foo={x:1,y:2,z:3};');
         assert.deepEqual(map.sourcesContent, ['var foo = {"x": 1, y: 2, \'z\': 3};']);

test/mocha/minify.js

@@ -48,8 +48,8 @@ describe("minify", function() {
             var result = UglifyJS.minify(code, {
                 mangle: {
                     cache: cache,
-                    toplevel: true
-                }
+                    toplevel: true,
+                },
             });
             if (result.error) throw result.error;
             original += code;
@@ -79,9 +79,9 @@ describe("minify", function() {
             var code = read("test/input/issue-1242/" + file);
             var result = UglifyJS.minify(code, {
                 mangle: {
-                    toplevel: true
+                    toplevel: true,
                 },
-                nameCache: cache
+                nameCache: cache,
             });
             if (result.error) throw result.error;
             original += code;
@@ -110,10 +110,12 @@ describe("minify", function() {
             var result = UglifyJS.minify(code, {
                 compress: false,
                 mangle: {
-                    properties: true,
-                    toplevel: true
+                    properties: {
+                        domprops: true,
+                    },
+                    toplevel: true,
                 },
-                nameCache: cache
+                nameCache: cache,
             });
             if (result.error) throw result.error;
             original += code;
@@ -160,8 +162,9 @@ describe("minify", function() {
             var js = 'var foo = {"x": 1, y: 2, \'z\': 3};';
             var result = UglifyJS.minify(js, {
                 output: {
-                    keep_quoted_props: true
-                }});
+                    keep_quoted_props: true,
+                },
+            });
             assert.strictEqual(result.code, 'var foo={"x":1,y:2,"z":3};');
         });
         it("Should preserve quote styles when quote_style is 3", function() {
@@ -169,8 +172,9 @@ describe("minify", function() {
             var result = UglifyJS.minify(js, {
                 output: {
                     keep_quoted_props: true,
-                    quote_style: 3
-                }});
+                    quote_style: 3,
+                },
+            });
             assert.strictEqual(result.code, 'var foo={"x":1,y:2,\'z\':3};');
         });
         it("Should not preserve quotes in object literals when disabled", function() {
@@ -178,8 +182,9 @@ describe("minify", function() {
             var result = UglifyJS.minify(js, {
                 output: {
                     keep_quoted_props: false,
-                    quote_style: 3
-                }});
+                    quote_style: 3,
+                },
+            });
             assert.strictEqual(result.code, 'var foo={x:1,y:2,z:3};');
         });
     });
@@ -188,32 +193,30 @@ describe("minify", function() {
         it("Shouldn't mangle quoted properties", function() {
             var js = 'a["foo"] = "bar"; a.color = "red"; x = {"bar": 10};';
             var result = UglifyJS.minify(js, {
-                compress: {
-                    properties: false
-                },
+                compress: true,
                 mangle: {
                     properties: {
-                        keep_quoted: true
-                    }
+                        domprops: true,
+                        keep_quoted: true,
+                    },
                 },
                 output: {
                     keep_quoted_props: true,
-                    quote_style: 3
-                }
+                    quote_style: 3,
+                },
             });
-            assert.strictEqual(result.code,
-                    'a["foo"]="bar",a.a="red",x={"bar":10};');
+            assert.strictEqual(result.code, 'a["foo"]="bar",a.a="red",x={"bar":10};');
         });
         it("Should not mangle quoted property within dead code", function() {
-            var result = UglifyJS.minify('({ "keep": 1 }); g.keep = g.change;', {
+            var result = UglifyJS.minify('({ "keep": 1 }); g.keep = g.change = 42;', {
                 mangle: {
                     properties: {
-                        keep_quoted: true
-                    }
-                }
+                        keep_quoted: true,
+                    },
+                },
             });
             if (result.error) throw result.error;
-            assert.strictEqual(result.code, "g.keep=g.g;");
+            assert.strictEqual(result.code, "g.keep=g.g=42;");
         });
     });
 
@@ -223,7 +226,7 @@ describe("minify", function() {
                 output: {
                     comments: "all",
                     beautify: false,
-                }
+                },
             });
             var code = result.code;
             assert.strictEqual(code, "//  comment1   comment2\nbar();");
@@ -233,7 +236,7 @@ describe("minify", function() {
                 output: {
                     comments: "all",
                     beautify: false,
-                }
+                },
             });
             var code = result.code;
             assert.strictEqual(code, "var a=function(){foo()}();");
@@ -301,7 +304,7 @@ describe("minify", function() {
                 compress: false,
                 mangle: false,
                 output: {
-                    ast: true
+                    ast: true,
                 },
             }).ast;
             assert.strictEqual(ast.TYPE, "Toplevel");
@@ -312,9 +315,9 @@ describe("minify", function() {
             var stat = ast.body[0].body[0];
             UglifyJS.minify(ast, {
                 compress: {
-                    sequences: false
+                    sequences: false,
                 },
-                mangle: false
+                mangle: false,
             });
             assert.ok(stat.body);
             assert.strictEqual(stat.print_to_string(), "a=x()");

test/mocha/number-literal.js

@@ -50,12 +50,10 @@ describe("Number literals", function() {
             "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,
-                },
+                expression: true,
             });
             if (result.error) throw result.error;
-            assert.strictEqual(result.code, "42;");
+            assert.strictEqual(result.code, "42");
         });
     });
     it("Should reject invalid use of underscore", function() {

test/mocha/reduce.js

@@ -236,9 +236,9 @@ describe("test/reduce.js", function() {
     });
     it("Should report trailing whitespace difference in stringified format", function() {
         var code = [
-            "for (var a in (1 - .8).toString()) {",
+            "[].forEach.call((1 - .8).toString(), function() {",
             "    console.log();",
-            "}",
+            "});",
         ].join("\n");
         var result = reduce_test(code, {
             compress: {
@@ -333,6 +333,7 @@ describe("test/reduce.js", function() {
                 unsafe_math: true,
             },
             mangle: false,
+            module: false,
         });
         if (result.error) throw result.error;
         assert.strictEqual(result.code, [
@@ -346,7 +347,8 @@ describe("test/reduce.js", function() {
             '//   "compress": {',
             '//     "unsafe_math": true',
             '//   },',
-            '//   "mangle": false',
+            '//   "mangle": false,',
+            '//   "module": false',
             "// }",
         ].join("\n"));
     });
@@ -449,6 +451,27 @@ describe("test/reduce.js", function() {
         ].join("\n"));
     });
     it("Should transform `export default function` correctly", function() {
+        if (semver.satisfies(process.version, "<8")) return;
+        var code = [
+            "export default function f(a) {",
+            "    for (var k in a)",
+            "        console.log(k);",
+            "    (async function() {})();",
+            "}",
+            "f(this);",
+        ].join("\n");
+        var result = reduce_test(code, {
+            mangle: false,
+        });
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, [
+            "// Can't reproduce test failure",
+            "// minify options: {",
+            '//   "mangle": false',
+            "// }",
+        ].join("\n"));
+    });
+    it("Should transform `export default (function)` correctly", function() {
         var code = [
             "for (var k in this)",
             "    console.log(k);",

test/mocha/sourcemaps.js

@@ -19,11 +19,11 @@ function source_map(code) {
 function get_map() {
     return {
         "version": 3,
-        "sources": ["index.js"],
+        "sources": [ "index.js" ],
         "names": [],
         "mappings": ";;AAAA,IAAI,MAAM,SAAN,GAAM;AAAA,SAAK,SAAS,CAAd;AAAA,CAAV;AACA,QAAQ,GAAR,CAAY,IAAI,KAAJ,CAAZ",
         "file": "bundle.js",
-        "sourcesContent": ["let foo = x => \"foo \" + x;\nconsole.log(foo(\"bar\"));"]
+        "sourcesContent": [ "let foo = x => \"foo \" + x;\nconsole.log(foo(\"bar\"));" ],
     };
 }
 
@@ -42,7 +42,7 @@ function prepare_map(sourceMap) {
         sourceMap: {
             content: sourceMap,
             includeSources: true,
-        }
+        },
     });
     if (result.error) throw result.error;
     return JSON.parse(result.map);
@@ -112,7 +112,7 @@ describe("sourcemaps", function() {
         });
         if (result.error) throw result.error;
         assert.strictEqual(result.code, "class A{static P=42;set#q(s){}}");
-        assert.strictEqual(result.map, '{"version":3,"sources":["0"],"names":["A","P","#q","v"],"mappings":"MAAMA,EACFC,SAAW,GACXC,MAAOC"}');
+        assert.strictEqual(result.map, '{"version":3,"sources":["0"],"names":["A","P","#q","v"],"mappings":"MAAMA,EACFC,SAAW,GACXC,MAAOC,IACX"}');
     });
     it("Should mark array/object literals", function() {
         var result = UglifyJS.minify([
@@ -124,7 +124,7 @@ describe("sourcemaps", function() {
         });
         if (result.error) throw result.error;
         assert.strictEqual(result.code, "({}).wat([]);");
-        assert.strictEqual(result.map, '{"version":3,"sources":["0"],"names":["wat"],"mappings":"CAAU,IACNA,IAAI"}');
+        assert.strictEqual(result.map, '{"version":3,"sources":["0"],"names":["wat"],"mappings":"CAAU,IACNA,IAAI,EAAE"}');
     });
     it("Should give correct sourceRoot", function() {
         var code = "console.log(42);";
@@ -135,7 +135,7 @@ describe("sourcemaps", function() {
         });
         if (result.error) throw result.error;
         assert.strictEqual(result.code, code);
-        assert.strictEqual(result.map, '{"version":3,"sourceRoot":"//foo.bar/","sources":["0"],"names":["console","log"],"mappings":"AAAAA,QAAQC,IAAI"}');
+        assert.strictEqual(result.map, '{"version":3,"sourceRoot":"//foo.bar/","sources":["0"],"names":["console","log"],"mappings":"AAAAA,QAAQC,IAAI,EAAE"}');
     });
     it("Should produce same source map with DOS or UNIX line endings", function() {
         var code = [
@@ -160,8 +160,8 @@ describe("sourcemaps", function() {
                 sourceMap: {
                     content: read("test/input/issue-1236/simple.js.map"),
                     filename: "simple.min.js",
-                    includeSources: true
-                }
+                    includeSources: true,
+                },
             });
             if (result.error) throw result.error;
             var map = JSON.parse(result.map);
@@ -175,8 +175,8 @@ describe("sourcemaps", function() {
                 sourceMap: {
                     content: "inline",
                     includeSources: true,
-                    url: "inline"
-                }
+                    url: "inline",
+                },
             });
             if (result.error) throw result.error;
             assert.strictEqual(result.code + "\n", read("test/input/issue-520/output.js"));
@@ -185,7 +185,7 @@ describe("sourcemaps", function() {
             var result = UglifyJS.minify(read("test/input/issue-1323/sample.js"), {
                 mangle: false,
                 sourceMap: {
-                    content: "inline"
+                    content: "inline",
                 },
                 warnings: true,
             });
@@ -206,7 +206,7 @@ describe("sourcemaps", function() {
             if (result.error) throw result.error;
             assert.strictEqual(result.code, [
                 "var Foo=function(){console.log(3)},bar=(new Foo,function(o){return o});",
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIiwiMSJdLCJuYW1lcyI6WyJGb28iLCJjb25zb2xlIiwibG9nIiwiYmFyIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFNQSxJQUFJLFdBQWdCQyxRQUFRQyxJQUFJLElDQWxDQyxLREEyQyxJQUFJSCxJQ0MvQyxTQUFjRyxHQUNWLE9BQU9BIn0=",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIiwiMSJdLCJuYW1lcyI6WyJGb28iLCJjb25zb2xlIiwibG9nIiwiYmFyIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFNQSxJQUFJLFdBQWdCQyxRQUFRQyxJQUFJLENBQUcsQ0FBRSxFQ0F2Q0MsS0RBMkMsSUFBSUgsSUNDL0MsU0FBY0csR0FDVixPQUFPQSxDQUNYIn0=",
             ].join("\n"));
             assert.deepEqual(result.warnings, [ "WARN: inline source map not found: 1" ]);
         });
@@ -239,13 +239,13 @@ describe("sourcemaps", function() {
                 sourceMap: {
                     content: "inline",
                     includeSources: true,
-                    url: "inline"
-                }
+                    url: "inline",
+                },
             });
             if (result.error) throw result.error;
             assert.strictEqual(result.code + "\n", read("test/input/issue-3294/output.js"));
         });
-        it("Should work in presence of unrecognised annotations", function() {
+        it("Should work in presence of unrecognized annotations", function() {
             var result = UglifyJS.minify(read("test/input/issue-3441/input.js"), {
                 compress: false,
                 mangle: false,
@@ -255,7 +255,7 @@ describe("sourcemaps", function() {
             });
             if (result.error) throw result.error;
             assert.strictEqual(result.code, '(function(){console.log("hello")}).call(this);');
-            assert.strictEqual(result.map, '{"version":3,"sources":["main.coffee"],"names":["console","log"],"mappings":"CAAA,WAAAA,QAAQC,IAAI"}');
+            assert.strictEqual(result.map, '{"version":3,"sources":["main.coffee"],"names":["console","log"],"mappings":"CAAA,WAAAA,QAAQC,IAAI,OAAZ"}');
         });
         it("Should not overwrite existing sourcesContent", function() {
             var result = UglifyJS.minify({
@@ -296,16 +296,16 @@ describe("sourcemaps", function() {
         it("Should append source map to output js when sourceMapInline is enabled", function() {
             var result = UglifyJS.minify('var a = function(foo) { return foo; };', {
                 sourceMap: {
-                    url: "inline"
-                }
+                    url: "inline",
+                },
             });
             if (result.error) throw result.error;
             var code = result.code;
             assert.strictEqual(code, "var a=function(n){return n};\n" +
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsiYSIsImZvbyJdLCJtYXBwaW5ncyI6IkFBQUEsSUFBSUEsRUFBSSxTQUFTQyxHQUFPLE9BQU9BIn0=");
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsiYSIsImZvbyJdLCJtYXBwaW5ncyI6IkFBQUEsSUFBSUEsRUFBSSxTQUFTQyxHQUFPLE9BQU9BLENBQUsifQ==");
         });
         it("Should not append source map to output js when sourceMapInline is not enabled", function() {
-            var result = UglifyJS.minify('var a = function(foo) { return foo; };');
+            var result = UglifyJS.minify("var a = function(foo) { return foo; };");
             if (result.error) throw result.error;
             var code = result.code;
             assert.strictEqual(code, "var a=function(n){return n};");
@@ -316,11 +316,11 @@ describe("sourcemaps", function() {
                     directives: false,
                 },
                 output: {
-                    max_line_len: 20
+                    max_line_len: 20,
                 },
                 sourceMap: {
-                    url: "inline"
-                }
+                    url: "inline",
+                },
             });
             if (result.error) throw result.error;
             assert.strictEqual(result.code, read("test/input/issue-505/output.js"));
@@ -334,7 +334,7 @@ describe("sourcemaps", function() {
                 sourceMap: {
                     includeSources: true,
                     url: "inline",
-                }
+                },
             });
             if (result.error) throw result.error;
             var map = JSON.parse(result.map);
@@ -348,7 +348,7 @@ describe("sourcemaps", function() {
                 sourceMap: {
                     content: "inline",
                     includeSources: true,
-                }
+                },
             });
             if (result.error) throw result.error;
             map = JSON.parse(result.map);

test/mozilla-ast.js

@@ -9,19 +9,22 @@ function beautify(ast) {
     var beautified = UglifyJS.minify(ast, {
         compress: false,
         mangle: false,
+        module: ufuzz.module,
         output: {
+            ast: true,
             beautify: true,
             braces: true,
         },
     });
-    if (beautified.error) return beautified;
-    return UglifyJS.minify(beautified.code, {
-        compress: false,
-        mangle: false,
-        output: {
-            ast: true,
-        },
-    });
+    if (!beautified.error) {
+        var verify = UglifyJS.minify(beautified.code, {
+            compress: false,
+            mangle: false,
+            module: ufuzz.module,
+        });
+        if (verify.error) return verify;
+    }
+    return beautified;
 }
 
 function validate(ast) {
@@ -35,6 +38,7 @@ function validate(ast) {
     return UglifyJS.minify(ast, {
         compress: false,
         mangle: false,
+        module: ufuzz.module,
         output: {
             ast: true,
         },
@@ -57,12 +61,12 @@ function test(input, to_moz, description, skip_on_error, beautified) {
         var ast = UglifyJS.AST_Node.from_mozilla_ast(to_moz(input));
     } catch (e) {
         if (skip_on_error) return true;
-        console.log("//=============================================================");
-        console.log("//", description, "failed... round", round);
-        console.log(e);
-        console.log("// original code");
-        if (beautified === true) console.log("// (beautified)");
-        console.log(input.code);
+        console.error("//=============================================================");
+        console.error("//", description, "failed... round", round);
+        console.error(e);
+        console.error("// original code");
+        if (beautified === true) console.error("// (beautified)");
+        console.error(input.code);
         return false;
     }
     var transformed = validate(ast);
@@ -74,34 +78,34 @@ function test(input, to_moz, description, skip_on_error, beautified) {
                 if (!test(beautified, to_moz, description, skip_on_error, true)) return false;
             }
         }
-        console.log("//=============================================================");
-        console.log("// !!!!!! Failed... round", round);
-        console.log("// original code");
+        console.error("//=============================================================");
+        console.error("// !!!!!! Failed... round", round);
+        console.error("// original code");
         if (beautified.error) {
-            console.log("// !!! beautify failed !!!");
-            console.log(beautified.error.stack);
+            console.error("// !!! beautify failed !!!");
+            console.error(beautified.error.stack);
         } else if (beautified === true) {
-            console.log("// (beautified)");
+            console.error("// (beautified)");
         }
-        console.log(input.raw);
-        console.log();
-        console.log();
-        console.log("//-------------------------------------------------------------");
-        console.log("//", description);
+        console.error(input.raw);
+        console.error();
+        console.error();
+        console.error("//-------------------------------------------------------------");
+        console.error("//", description);
         if (transformed.error) {
-            console.log(transformed.error.stack);
+            console.error(transformed.error.stack);
         } else {
             beautified = beautify(transformed.ast);
             if (beautified.error) {
-                console.log("// !!! beautify failed !!!");
-                console.log(beautified.error.stack);
-                console.log(transformed.code);
+                console.error("// !!! beautify failed !!!");
+                console.error(beautified.error.stack);
+                console.error(transformed.code);
             } else {
-                console.log("// (beautified)");
-                console.log(beautified.code);
+                console.error("// (beautified)");
+                console.error(beautified.code);
             }
         }
-        console.log("!!!!!! Failed... round", round);
+        console.error("!!!!!! Failed... round", round);
         return false;
     }
     return true;
@@ -115,9 +119,29 @@ for (var round = 1; round <= num_iterations; round++) {
     var code = ufuzz.createTopLevelCode();
     minify_options.forEach(function(options) {
         var ok = true;
-        var input = UglifyJS.minify(options ? UglifyJS.minify(code, JSON.parse(options)).code : code, {
+        var minified;
+        if (options) {
+            var o = JSON.parse(options);
+            o.module = ufuzz.module;
+            minified = UglifyJS.minify(code, o);
+            if (minified.error) {
+                console.log("//=============================================================");
+                console.log("// minify() failed... round", round);
+                console.log("// original code");
+                console.log(code);
+                console.log();
+                console.log();
+                console.log("//-------------------------------------------------------------");
+                console.log("minify(options):");
+                console.log(JSON.stringify(o, null, 2));
+                return;
+            }
+            minified = minified.code;
+        }
+        var input = UglifyJS.minify(minified || code, {
             compress: false,
             mangle: false,
+            module: ufuzz.module,
             output: {
                 ast: true,
             },
@@ -125,11 +149,27 @@ for (var round = 1; round <= num_iterations; round++) {
         input.raw = options ? input.code : code;
         if (input.error) {
             ok = false;
-            console.log("//=============================================================");
-            console.log("// minify() failed... round", round);
-            console.log(input.error);
-            console.log("// original code");
-            console.log(code);
+            console.error("//=============================================================");
+            console.error("// parse() failed... round", round);
+            console.error("// original code");
+            console.error(code);
+            console.error();
+            console.error();
+            if (options) {
+                console.error("//-------------------------------------------------------------");
+                console.error("// minified code");
+                console.error(minified);
+                console.error();
+                console.error();
+                console.error("//-------------------------------------------------------------");
+                console.error("minify(options):");
+                console.error(JSON.stringify(o, null, 2));
+                console.error();
+                console.error();
+            }
+            console.error("//-------------------------------------------------------------");
+            console.error("// parse() error");
+            console.error(input.error);
         }
         if (ok) ok = test(input, function(input) {
             return input.ast.to_mozilla_ast();
@@ -141,7 +181,10 @@ for (var round = 1; round <= num_iterations; round++) {
                 sourceType: "module",
             });
         }, "acorn.parse()", !ufuzz.verbose);
-        if (!ok) process.exit(1);
+        if (!ok && isFinite(num_iterations)) {
+            console.log();
+            process.exit(1);
+        }
     });
 }
 console.log();

test/node.js

@@ -1,6 +1,6 @@
 var fs = require("fs");
 
-new Function("exports", require("../tools/node").FILES.map(function(file) {
+new Function("domprops", "exports", require("../tools/node").FILES.map(function(file) {
     if (/exports\.js$/.test(file)) file = require.resolve("./exports");
     return fs.readFileSync(file, "utf8");
-}).join("\n\n"))(exports);
+}).join("\n\n"))(require("../tools/domprops.json"), exports);

test/reduce.js

@@ -20,6 +20,9 @@ Error.stackTraceLimit = Infinity;
 module.exports = function reduce_test(testcase, minify_options, reduce_options) {
     minify_options = minify_options || {};
     reduce_options = reduce_options || {};
+    var parse_options = {
+        module: minify_options.module || minify_options.module === undefined,
+    }
     var print_options = {};
     [
         "ie",
@@ -160,6 +163,11 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 return expr instanceof U.AST_Spread ? expr.expression : expr;
             }
         }
+        else if (node instanceof U.AST_Await) {
+            node.start._permute++;
+            CHANGED = true;
+            return node.expression;
+        }
         else if (node instanceof U.AST_Binary) {
             var permute = ((node.start._permute += step) * steps | 0) % 4;
             var expr = [
@@ -185,7 +193,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
         }
         else if (node instanceof U.AST_BlockStatement) {
             if (in_list && node.body.filter(function(node) {
-                return node instanceof U.AST_Const;
+                return node instanceof U.AST_Const || node instanceof U.AST_Let;
             }).length == 0) {
                 node.start._permute++;
                 CHANGED = true;
@@ -241,23 +249,6 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             CHANGED = true;
             return node.name;
         }
-        else if (node instanceof U.AST_DestructuredArray) {
-            var expr = node.elements[0];
-            if (expr && !(expr instanceof U.AST_Hole)) {
-                node.start._permute++;
-                CHANGED = true;
-                return expr;
-            }
-        }
-        else if (node instanceof U.AST_DestructuredObject) {
-            // first property's value
-            var expr = node.properties[0];
-            if (expr) {
-                node.start._permute++;
-                CHANGED = true;
-                return expr.value;
-            }
-        }
         else if (node instanceof U.AST_Defun) {
             switch (((node.start._permute += step) * steps | 0) % 2) {
               case 0:
@@ -275,6 +266,23 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 }
             }
         }
+        else if (node instanceof U.AST_DestructuredArray) {
+            var expr = node.elements[0];
+            if (expr && !(expr instanceof U.AST_Hole)) {
+                node.start._permute++;
+                CHANGED = true;
+                return expr;
+            }
+        }
+        else if (node instanceof U.AST_DestructuredObject) {
+            // first property's value
+            var expr = node.properties[0];
+            if (expr) {
+                node.start._permute++;
+                CHANGED = true;
+                return expr.value;
+            }
+        }
         else if (node instanceof U.AST_DWLoop) {
             var expr = [
                 node.condition,
@@ -296,6 +304,16 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 return to_statement(expr);
             }
         }
+        else if (node instanceof U.AST_ExportDeclaration) {
+            node.start._permute++;
+            CHANGED = true;
+            return node.body;
+        }
+        else if (node instanceof U.AST_ExportDefault) {
+            node.start._permute++;
+            CHANGED = true;
+            return to_statement(node.body);
+        }
         else if (node instanceof U.AST_Finally) {
             // drop finally block
             node.start._permute++;
@@ -317,19 +335,21 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
         }
         else if (node instanceof U.AST_ForEnumeration) {
             var expr;
-            switch ((node.start._permute * steps | 0) % 3) {
+            switch ((node.start._permute * steps | 0) % 4) {
               case 0:
-                if (node.init instanceof U.AST_Definitions) {
-                    if (node.init instanceof U.AST_Const) break;
-                    if (node.init.definitions[0].name instanceof U.AST_Destructured) break;
-                }
-                expr = node.init;
-                break;
-              case 1:
                 expr = node.object;
                 break;
+              case 1:
+                expr = wrap_with_console_log(node.object);
+                break;
               case 2:
-                if (!has_loopcontrol(node.body, node, parent)) expr = node.body;
+                if (has_loopcontrol(node.body, node, parent)) break;
+                expr = node.body;
+                break;
+              case 3:
+                if (!(node.init instanceof U.AST_Var)) break;
+                if (node.init.definitions[0].name instanceof U.AST_Destructured) break;
+                expr = node.init;
                 break;
             }
             node.start._permute += step;
@@ -343,14 +363,31 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 node.condition,
                 node.body,
                 node.alternative,
-            ][ (node.start._permute * steps | 0) % 3 ];
+                node,
+            ][ (node.start._permute * steps | 0) % 4 ];
             node.start._permute += step;
-            if (expr) {
+            if (expr === node) {
+                if (node.alternative) {
+                    expr = node.clone();
+                    expr.alternative = null;
+                    CHANGED = true;
+                    return expr;
+                }
+            } else if (expr) {
                 // replace if statement with its condition, then block or else block
                 CHANGED = true;
                 return to_statement(expr);
             }
         }
+        else if (node instanceof U.AST_LabeledStatement) {
+            if (node.body instanceof U.AST_Statement
+                && !has_loopcontrol(node.body, node.body, node)) {
+                // replace labelled statement with its non-labelled body
+                node.start._permute = REPLACEMENTS.length;
+                CHANGED = true;
+                return node.body;
+            }
+        }
         else if (node instanceof U.AST_Object) {
             // first property's value
             var expr = node.properties[0];
@@ -441,13 +478,14 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 return to_statement(node.definitions[0].value);
             }
         }
-        else if (node instanceof U.AST_LabeledStatement) {
-            if (node.body instanceof U.AST_Statement
-                && !has_loopcontrol(node.body, node.body, node)) {
-                // replace labelled statement with its non-labelled body
-                node.start._permute = REPLACEMENTS.length;
+        else if (node instanceof U.AST_VarDef) {
+            if (node.value && !(node.name instanceof U.AST_Destructured || parent instanceof U.AST_Const)) {
+                node.start._permute++;
                 CHANGED = true;
-                return node.body;
+                return new U.AST_VarDef({
+                    name: node.name,
+                    start: {},
+                });
             }
         }
 
@@ -514,7 +552,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
     var before_iterations, diff_error_message, passes = 3, testcase_ast;
     for (var pass = 1; pass <= passes; pass++) {
         if (before_iterations !== testcase) {
-            testcase_ast = U.parse(testcase);
+            testcase_ast = U.parse(testcase, parse_options);
             if (diff_error_message === testcase) {
                 // only difference detected is in error message, so expose that and try again
                 testcase_ast.transform(new U.TreeTransformer(function(node, descend) {
@@ -536,7 +574,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     testcase = code;
                     differs = diff;
                 } else {
-                    testcase_ast = U.parse(testcase);
+                    testcase_ast = U.parse(testcase, parse_options);
                 }
             }
             diff_error_message = null;
@@ -596,6 +634,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
     var beautified = U.minify(testcase, {
         compress: false,
         mangle: false,
+        module: minify_options.module,
         output: function() {
             var options = JSON.parse(JSON.stringify(print_options));
             options.beautify = true;
@@ -748,7 +787,7 @@ function run_code(code, toplevel, result_cache, timeout) {
     if (!value) {
         var start = Date.now();
         result_cache[key] = value = {
-            result: sandbox.run_code(sandbox.patch_module_statements(code), toplevel, timeout),
+            result: sandbox.run_code(code, toplevel, timeout),
             elapsed: Date.now() - start,
         };
     }
@@ -776,13 +815,7 @@ function compare_run_code(code, minify_options, result_cache, max_timeout) {
     };
 
     function run(code, timeout) {
-        if (minify_options.module) code = [
-            '"use strict";',
-            "(async function(){",
-            code,
-            "})();"
-        ].join("\n");
-        return run_code(code, toplevel, result_cache, timeout);
+        return run_code(sandbox.patch_module_statements(code, minify_options.module), toplevel, result_cache, timeout);
     }
 }
 

test/release/benchmark.js

@@ -1,11 +1,8 @@
 require("./run")([
-    "-b",
-    "-b braces",
-    "-m",
-    "-mc passes=3",
-    "-mc passes=3,toplevel",
+    "-mb braces",
+    "--toplevel -c",
+    "--no-module -mc",
     "-mc passes=3,unsafe",
-    "-mc keep_fargs=false,passes=3",
     "-mc keep_fargs=false,passes=3,pure_getters,unsafe,unsafe_comps,unsafe_math,unsafe_proto",
 ].map(function(options) {
     var args = options.split(/ /);

test/release/buble.sh

@@ -41,6 +41,11 @@ rm -rf tmp/buble \
 @@ -309 +309 @@ export default class BlockStatement extends Node {
 -                               let cont = false; // TODO implement proper continue...
 +                               let cont = !declarations; // TODO implement proper continue...
+--- a/src/program/types/VariableDeclaration.js
++++ b/src/program/types/VariableDeclaration.js
+@@ -38 +38 @@ export default class VariableDeclaration extends Node {
+-                                               code.remove(c, declarator.id.start);
++                                               code.remove(c, declarator.id.start, lastDeclaratorIsPattern);
 EOF
 ERR=$?; if [ "$ERR" != "0" ]; then echo "Error: $ERR"; exit $ERR; fi
 minify_in_situ "src" \

test/release/install.sh

@@ -36,7 +36,7 @@ EOF
 }
 if [ $NATIVE ]; then unset -f timeout; fi
 
-while !(git clone --branch v1.6.0 --depth 1 https://github.com/jasongin/nvs.git ~/.nvs); do
+while !(git clone --branch v1.6.2 --depth 1 https://github.com/jasongin/nvs.git ~/.nvs); do
     rm -rf ~/.nvs
 done
 while ! timeout 60 bash -c ". ~/.nvs/nvs.sh add $NODE && nvs use $NODE"; do
@@ -48,7 +48,10 @@ done
 nvs use $NODE
 node --version
 npm config set audit false
-npm config set optional false
+npm config set fund false
+npm config set loglevel error
+npm config set omit optional || true
+npm config set optional false || true
 npm config set save false
 npm config set strict-ssl false
 npm config set update-notifier false

test/release/jetstream.js

@@ -4,6 +4,7 @@ require("./run")([
 ].map(function(options) {
     var args = options.split(/ /);
     args.unshift("test/jetstream.js");
-    args.push("-b", "beautify=false,webkit");
+    args.push("-O", "webkit");
+    args.push("--no-module");
     return args;
 }));

test/release/sucrase.sh

@@ -35,18 +35,27 @@ npm_install() {
     done
 }
 
+workaround() {
+    FILE="$1"
+    echo 'Monkey patching' $FILE
+    CODE=`cat $FILE`
+    sed -E 's/for ?\((var [^;{]+;)/\1for\(;/g' > $FILE <<EOF
+$CODE
+EOF
+}
+
 rm -rf tmp/sucrase \
 && git clone https://github.com/alangpierce/sucrase.git tmp/sucrase \
 && cd tmp/sucrase \
 && rm -rf .git/hooks \
-&& git checkout 38b66f3009feb76750a799deea211adcc83574f1 \
+&& git checkout 7284b3733aa114b3f4f5371e36ff5a4704ec860e \
 && patch -l -p1 <<EOF
 --- a/package.json
 +++ b/package.json
 @@ -25 +24,0 @@
 -    "prepublishOnly": "yarn clean && yarn build",
-@@ -65 +63,0 @@
--    "test262-harness": "^6.5.0",
+@@ -69 +67,0 @@
+-    "test262-harness": "^10.0.0",
 --- a/script/build.ts
 +++ b/script/build.ts
 @@ -16 +15,0 @@ async function main(): Promise<void> {
@@ -57,11 +66,11 @@ rm -rf tmp/sucrase \
 -    () => buildIntegration("./integrations/webpack-loader"),
 -    () => buildIntegration("./integrations/webpack-object-rest-spread-plugin"),
 -    () => buildWebsite(),
-@@ -66,3 +59,0 @@ async function buildSucrase(): Promise<void> {
+@@ -62,3 +55,0 @@ async function buildSucrase(): Promise<void> {
 -    // Also add in .d.ts files from tsc, which only need to be compiled once.
 -    await run(\`\${TSC} --project ./src --outDir ./dist-types\`);
--    await mergeDirectoryContents("./dist-types/src", "./dist");
-@@ -70 +61 @@ async function buildSucrase(): Promise<void> {
+-    await mergeDirectoryContents("./dist-types/src", "./dist/types");
+@@ -66 +57 @@ async function buildSucrase(): Promise<void> {
 -    await run("yarn link");
 +    await run("npm link");
 --- a/src/identifyShadowedGlobals.ts
@@ -70,28 +79,38 @@ rm -rf tmp/sucrase \
 +export { identifyShadowedGlobals as HACK };
 --- a/src/parser/tokenizer/state.ts
 +++ b/src/parser/tokenizer/state.ts
-@@ -100,0 +101 @@ export default class State {
+@@ -106,0 +107 @@ export default class State {
 +export { State as HACK };
 --- a/src/transformers/JSXTransformer.ts
 +++ b/src/transformers/JSXTransformer.ts
-@@ -253,0 +254 @@ export default class JSXTransformer extends Transformer {
+@@ -560,0 +561 @@ export default class JSXTransformer extends Transformer {
 +export { JSXTransformer as HACK };
 --- a/src/util/getClassInfo.ts
 +++ b/src/util/getClassInfo.ts
-@@ -164,0 +165 @@ export default function getClassInfo(
+@@ -195,0 +196 @@ export default function getClassInfo(
 +export { getClassInfo as HACK };
 --- a/src/util/getDeclarationInfo.ts
 +++ b/src/util/getDeclarationInfo.ts
 @@ -40,0 +41 @@ export default function getDeclarationInfo(tokens: TokenProcessor): DeclarationI
 +export { getDeclarationInfo as HACK };
+--- a/src/util/getImportExportSpecifierInfo.ts
++++ b/src/util/getImportExportSpecifierInfo.ts
+@@ -87,0 +88 @@ export default function getImportExportSpecifierInfo(
++export { getImportExportSpecifierInfo as HACK };
 --- a/src/util/getJSXPragmaInfo.ts
 +++ b/src/util/getJSXPragmaInfo.ts
 @@ -14,0 +15 @@ export default function getJSXPragmaInfo(options: Options): JSXPragmaInfo {
 +export { getJSXPragmaInfo as HACK };
+--- a/test/source-maps-test.ts
++++ b/test/source-maps-test.ts
+@@ -26,0 +27 @@ var _a = require('./a'); var _a2 = _interopRequireDefault(_a);
++delete result.sourceMap.ignoreList;
 EOF
 ERR=$?; if [ "$ERR" != "0" ]; then echo "Error: $ERR"; exit $ERR; fi
 npm_install esbuild-wasm@0.8.56 \
 && minify_in_situ "src" \
+&& workaround src/parser/plugins/typescript.ts\
+&& workaround src/transformers/CJSImportTransformer.ts\
 && rm -rf node_modules \
 && npm_install \
 && npm run clean \