Merge pull request #2161 from alexlamsl/harmony-v3.0.20

Merging from master for 3.0.20

.travis.yml

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

README.md

@@ -102,6 +102,7 @@ a double dash to prevent input files being used as option arguments:
                                 sequences.
     --config-file <file>        Read `minify()` options from JSON file.
     -d, --define <expr>[=value] Global definitions.
+    --ecma <version>            Specifiy ECMAScript release: 5, 6, 7 or 8.
     --ie8                       Support non-standard Internet Explorer 8.
                                 Equivalent to setting `ie8: true` in `minify()`
                                 for `compress`, `mangle` and `output` options.
@@ -569,7 +570,8 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   comparison are switching. Compression only works if both `comparisons` and
   `unsafe_comps` are both set to true.
 
-- `unsafe_Func` (default: false) -- compress and mangle `Function(args, code)`.
+- `unsafe_Func` (default: false) -- compress and mangle `Function(args, code)`
+  when both `args` and `code` are string literals.
 
 - `unsafe_math` (default: false) -- optimize numerical expressions like
   `2 * x * 3` into `6 * x`, which may give imprecise floating point results.
@@ -589,6 +591,10 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 
 - `evaluate` -- attempt to evaluate constant expressions
 
+- `arrows` (default `true`) -- convert ES5 style anonymous function expressions
+  to arrow functions if permissible by language semantics.
+  Note: `arrows` requires that the `ecma` compress option is set to `6` or greater.
+
 - `booleans` -- various optimizations for boolean context, for example `!!a
   ? b : c → a ? b : c`
 
@@ -612,6 +618,8 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 
 - `if_return` -- optimizations for if/return and if/continue
 
+- `inline` -- embed simple functions
+
 - `join_vars` -- join consecutive `var` statements
 
 - `cascade` -- small optimization for sequences, transform `x, x` into `x`
@@ -677,17 +685,22 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 
 ## Mangle options
 
-- `reserved` - pass an array of identifiers that should be excluded from mangling
+- `reserved` (default `[]`). Pass an array of identifiers that should be
+  excluded from mangling. Example: `["foo", "bar"]`.
 
-- `toplevel` — mangle names declared in the top level scope (disabled by
-default).
+- `toplevel` (default `false`). Pass `true` to mangle names declared in the
+  top level scope.
 
-- `eval` — mangle names visible in scopes where eval or with are used
-(disabled by default).
+- `keep_fnames` (default `false`).  Pass `true` to not mangle function names.
+  Useful for code relying on `Function.prototype.name`. See also: the `keep_fnames`
+  [compress option](#compress-options).
 
-- `keep_fnames` -- default `false`.  Pass `true` to not mangle
-function names.  Useful for code relying on `Function.prototype.name`.
-See also: the `keep_fnames` [compress option](#compress-options).
+- `eval` (default `false`). Pass `true` to mangle names visible in scopes
+  where `eval` or `with` are used.
+
+- `safari10` (default `false`). Pass `true` to work around the Safari 10 loop
+  iterator [bug](https://bugs.webkit.org/show_bug.cgi?id=171041)
+  "Cannot declare a let variable twice".
 
 Examples:
 
@@ -762,7 +775,7 @@ can pass additional arguments that control the code output:
 - `quote_style` (default `0`) -- preferred quote style for strings (affects
   quoted property names and directives as well):
   - `0` -- prefers double quotes, switches to single quotes when there are
-    more double quotes in the string itself.
+    more double quotes in the string itself. `0` is best for gzip size.
   - `1` -- always use single quotes
   - `2` -- always use double quotes
   - `3` -- always use the original quotes

bin/uglifyjs

@@ -30,14 +30,7 @@ else if (process.argv.indexOf("options") >= 0) program.helpInformation = functio
     var options = UglifyJS.default_options();
     for (var option in options) {
         text.push("--" + (option == "output" ? "beautify" : option == "sourceMap" ? "source-map" : option) + " options:");
-        var defs = options[option];
-        var padding = "";
-        Object.keys(defs).map(function(name) {
-            if (padding.length < name.length) padding = Array(name.length + 1).join(" ");
-            return [ name, JSON.stringify(defs[name]) ];
-        }).forEach(function(tokens) {
-            text.push("  " + tokens[0] + padding.slice(tokens[0].length - 2) + tokens[1]);
-        });
+        text.push(format_object(options[option]));
         text.push("");
     }
     return text.join("\n");
@@ -51,6 +44,7 @@ program.option("-o, --output <file>", "Output file (default STDOUT).");
 program.option("--comments [filter]", "Preserve copyright comments in the output.");
 program.option("--config-file <file>", "Read minify() options from JSON file.");
 program.option("-d, --define <expr>[=value]", "Global definitions.", parse_js("define"));
+program.option("--ecma <version>", "Specifiy ECMAScript release: 5, 6, 7 or 8.");
 program.option("--ie8", "Support non-standard Internet Explorer 8.");
 program.option("--keep-fnames", "Do not mangle/drop function names. Useful for code relying on Function.prototype.name.");
 program.option("--name-cache <file>", "File to hold mangled name mappings.");
@@ -80,6 +74,10 @@ if (!program.output && program.sourceMap && program.sourceMap.url != "inline") {
         options[name] = program[name];
     }
 });
+if ("ecma" in program) {
+    if (program.ecma != (program.ecma | 0)) fatal("ERROR: ecma must be an integer");
+    options.ecma = program.ecma | 0;
+}
 if (program.beautify) {
     options.output = typeof program.beautify == "object" ? program.beautify : {};
     if (!("beautify" in options.output)) {
@@ -157,7 +155,7 @@ if (program.verbose) {
 }
 if (program.self) {
     if (program.args.length) {
-        console.error("WARN: Ignoring input files since --self was passed");
+        print_error("WARN: Ignoring input files since --self was passed");
     }
     if (!options.wrap) options.wrap = "UglifyJS";
     simple_glob(UglifyJS.FILES).forEach(function(name) {
@@ -187,7 +185,7 @@ function convert_ast(fn) {
 
 function run() {
     UglifyJS.AST_Node.warn_function = function(msg) {
-        console.error("WARN:", msg);
+        print_error("WARN: " + msg);
     };
     if (program.timings) options.timings = true;
     try {
@@ -216,7 +214,7 @@ function run() {
     if (result.error) {
         var ex = result.error;
         if (ex.name == "SyntaxError") {
-            console.error("Parse error at " + ex.filename + ":" + ex.line + "," + ex.col);
+            print_error("Parse error at " + ex.filename + ":" + ex.line + "," + ex.col);
             var col = ex.col;
             var lines = files[ex.filename].split(/\r?\n/);
             var line = lines[ex.line - 1];
@@ -230,17 +228,17 @@ function run() {
                     line = line.slice(col - limit);
                     col = limit;
                 }
-                console.error(line.slice(0, 80));
-                console.error(line.slice(0, col).replace(/\S/g, " ") + "^");
+                print_error(line.slice(0, 80));
+                print_error(line.slice(0, col).replace(/\S/g, " ") + "^");
             }
         }
         if (ex.defs) {
-            console.error("Supported options:");
-            console.error(ex.defs);
+            print_error("Supported options:");
+            print_error(format_object(ex.defs));
         }
         fatal(ex);
     } else if (program.output == "ast") {
-        console.log(JSON.stringify(result.ast, function(key, value) {
+        print(JSON.stringify(result.ast, function(key, value) {
             if (skip_key(key)) return;
             if (value instanceof UglifyJS.AST_Token) return;
             if (value instanceof UglifyJS.Dictionary) return;
@@ -256,7 +254,7 @@ function run() {
             return value;
         }, 2));
     } else if (program.output == "spidermonkey") {
-        console.log(JSON.stringify(UglifyJS.minify(result.code, {
+        print(JSON.stringify(UglifyJS.minify(result.code, {
             compress: false,
             mangle: false,
             output: {
@@ -270,7 +268,7 @@ function run() {
             fs.writeFileSync(program.output + ".map", result.map);
         }
     } else {
-        console.log(result.code);
+        print(result.code);
     }
     if (program.nameCache) {
         fs.writeFileSync(program.nameCache, JSON.stringify(cache, function(key, value) {
@@ -278,13 +276,13 @@ function run() {
         }));
     }
     if (result.timings) for (var phase in result.timings) {
-        console.error("- " + phase + ": " + result.timings[phase].toFixed(3) + "s");
+        print_error("- " + phase + ": " + result.timings[phase].toFixed(3) + "s");
     }
 }
 
 function fatal(message) {
     if (message instanceof Error) message = message.stack.replace(/^\S*?Error:/, "ERROR:")
-    console.error(message);
+    print_error(message);
     process.exit(1);
 }
 
@@ -378,10 +376,10 @@ function parse_js(flag, constants) {
 function parse_source_map() {
     var parse = parse_js("sourceMap", true);
     return function(value, options) {
-        var hasContent = options && options.sourceMap && "content" in options.sourceMap;
+        var hasContent = options && "content" in options;
         var settings = parse(value, options);
         if (!hasContent && settings.content && settings.content != "inline") {
-            console.error("INFO: Using input source map:", settings.content);
+            print_error("INFO: Using input source map: " + settings.content);
             settings.content = read_file(settings.content, settings.content);
         }
         return settings;
@@ -403,3 +401,25 @@ function to_cache(key) {
 function skip_key(key) {
     return skip_keys.indexOf(key) >= 0;
 }
+
+function format_object(obj) {
+    var lines = [];
+    var padding = "";
+    Object.keys(obj).map(function(name) {
+        if (padding.length < name.length) padding = Array(name.length + 1).join(" ");
+        return [ name, JSON.stringify(obj[name]) ];
+    }).forEach(function(tokens) {
+        lines.push("  " + tokens[0] + padding.slice(tokens[0].length - 2) + tokens[1]);
+    });
+    return lines.join("\n");
+}
+
+function print_error(msg) {
+    process.stderr.write(msg);
+    process.stderr.write("\n");
+}
+
+function print(txt) {
+    process.stdout.write(txt);
+    process.stdout.write("\n");
+}

lib/ast.js

@@ -355,13 +355,14 @@ var AST_Expansion = DEFNODE("Expansion", "expression", {
     }
 });
 
-var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments is_generator", {
+var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments is_generator async", {
     $documentation: "Base class for functions",
     $propdoc: {
-        is_generator: "[boolean] is generatorFn or not",
         name: "[AST_SymbolDeclaration?] the name of this function",
         argnames: "[AST_SymbolFunarg|AST_Destructuring|AST_Expansion|AST_DefaultAssign*] array of function arguments, destructurings, or expanding arguments",
-        uses_arguments: "[boolean/S] tells whether this function accesses the arguments array"
+        uses_arguments: "[boolean/S] tells whether this function accesses the arguments array",
+        is_generator: "[boolean] is this a generator method",
+        async: "[boolean] is this method async",
     },
     args_as_names: function () {
         var out = [];
@@ -628,11 +629,11 @@ var AST_Const = DEFNODE("Const", null, {
     $documentation: "A `const` statement"
 }, AST_Definitions);
 
-var AST_NameImport = DEFNODE("NameImport", "foreign_name name", {
-    $documentation: "The part of the import statement that imports names from a module.",
+var AST_NameMapping = DEFNODE("NameMapping", "foreign_name name", {
+    $documentation: "The part of the export/import statement that declare names from a module.",
     $propdoc: {
-        foreign_name: "[AST_SymbolImportForeign] The name being imported (as specified in the module)",
-        name: "[AST_SymbolImport] The name as it becomes available to this module."
+        foreign_name: "[AST_SymbolExportForeign|AST_SymbolImportForeign] The name being exported/imported (as specified in the module)",
+        name: "[AST_SymbolExport|AST_SymbolImport] The name as it is visible to this module."
     },
     _walk: function (visitor) {
         return visitor._visit(this, function() {
@@ -646,7 +647,7 @@ var AST_Import = DEFNODE("Import", "imported_name imported_names module_name", {
     $documentation: "An `import` statement",
     $propdoc: {
         imported_name: "[AST_SymbolImport] The name of the variable holding the module's default export.",
-        imported_names: "[AST_NameImport*] The names of non-default imported variables",
+        imported_names: "[AST_NameMapping*] The names of non-default imported variables",
         module_name: "[AST_String] String literal describing where this module came from",
     },
     _walk: function(visitor) {
@@ -655,7 +656,7 @@ var AST_Import = DEFNODE("Import", "imported_name imported_names module_name", {
                 this.imported_name._walk(visitor);
             }
             if (this.imported_names) {
-                this.imported_names.forEach(function (name_import) {
+                this.imported_names.forEach(function(name_import) {
                     name_import._walk(visitor);
                 });
             }
@@ -669,7 +670,7 @@ var AST_Export = DEFNODE("Export", "exported_definition exported_value is_defaul
     $propdoc: {
         exported_definition: "[AST_Defun|AST_Definitions|AST_DefClass?] An exported definition",
         exported_value: "[AST_Node?] An exported value",
-        exported_names: "[AST_NameImport*?] List of exported names",
+        exported_names: "[AST_NameMapping*?] List of exported names",
         module_name: "[AST_String?] Name of the file to load exports from",
         is_default: "[Boolean] Whether this is the default exported value of this module"
     },
@@ -681,6 +682,14 @@ var AST_Export = DEFNODE("Export", "exported_definition exported_value is_defaul
             if (this.exported_value) {
                 this.exported_value._walk(visitor);
             }
+            if (this.exported_names) {
+                this.exported_names.forEach(function(name_export) {
+                    name_export._walk(visitor);
+                });
+            }
+            if (this.module_name) {
+                this.module_name._walk(visitor);
+            }
         });
     }
 }, AST_Statement);
@@ -893,11 +902,12 @@ var AST_ObjectGetter = DEFNODE("ObjectGetter", "quote static", {
     $documentation: "An object getter property",
 }, AST_ObjectProperty);
 
-var AST_ConciseMethod = DEFNODE("ConciseMethod", "quote static is_generator", {
+var AST_ConciseMethod = DEFNODE("ConciseMethod", "quote static is_generator async", {
     $propdoc: {
         quote: "[string|undefined] the original quote character, if any",
-        static: "[boolean] whether this method is static (classes only)",
-        is_generator: "[boolean] is generatorFn or not",
+        static: "[boolean] is this method static (classes only)",
+        is_generator: "[boolean] is this a generator method",
+        async: "[boolean] is this method async",
     },
     $documentation: "An ES6 concise method inside an object or class"
 }, AST_ObjectProperty);
@@ -994,7 +1004,7 @@ var AST_SymbolCatch = DEFNODE("SymbolCatch", null, {
 }, AST_SymbolBlockDeclaration);
 
 var AST_SymbolImport = DEFNODE("SymbolImport", null, {
-    $documentation: "Symbol refering to an imported name",
+    $documentation: "Symbol referring to an imported name",
 }, AST_SymbolBlockDeclaration);
 
 var AST_SymbolImportForeign = DEFNODE("SymbolImportForeign", null, {
@@ -1016,6 +1026,14 @@ var AST_SymbolRef = DEFNODE("SymbolRef", null, {
     $documentation: "Reference to some symbol (not definition/declaration)",
 }, AST_Symbol);
 
+var AST_SymbolExport = DEFNODE("SymbolExport", null, {
+    $documentation: "Symbol referring to a name to export",
+}, AST_SymbolRef);
+
+var AST_SymbolExportForeign = DEFNODE("SymbolExportForeign", null, {
+    $documentation: "A symbol exported from this module, but it is used in the other module, and its real name is irrelevant for this module's purposes",
+}, AST_Symbol);
+
 var AST_LabelRef = DEFNODE("LabelRef", null, {
     $documentation: "Reference to a label symbol",
 }, AST_Symbol);
@@ -1101,7 +1119,17 @@ var AST_True = DEFNODE("True", null, {
     value: true
 }, AST_Boolean);
 
-/* -----[ Yield ]----- */
+var AST_Await = DEFNODE("Await", "expression", {
+    $documentation: "An `await` statement",
+    $propdoc: {
+        expression: "[AST_Node] the mandatory expression being awaited",
+    },
+    _walk: function(visitor) {
+        return visitor._visit(this, function(){
+            this.expression._walk(visitor);
+        });
+    }
+});
 
 var AST_Yield = DEFNODE("Yield", "expression is_star", {
     $documentation: "A `yield` statement",

lib/minify.js

@@ -32,6 +32,7 @@ function minify(files, options) {
     try {
         options = defaults(options, {
             compress: {},
+            ecma: undefined,
             ie8: false,
             keep_fnames: false,
             mangle: {},
@@ -46,6 +47,7 @@ function minify(files, options) {
         var timings = options.timings && {
             start: Date.now()
         };
+        set_shorthand("ecma", options, [ "parse", "compress", "output" ]);
         set_shorthand("ie8", options, [ "compress", "mangle", "output" ]);
         set_shorthand("keep_fnames", options, [ "compress", "mangle" ]);
         set_shorthand("toplevel", options, [ "compress", "mangle" ]);
@@ -88,7 +90,7 @@ function minify(files, options) {
             }
             options.parse = options.parse || {};
             options.parse.toplevel = null;
-            for (var name in files) {
+            for (var name in files) if (HOP(files, name)) {
                 options.parse.filename = name;
                 options.parse.toplevel = parse(files[name], options.parse);
                 if (options.sourceMap && options.sourceMap.content == "inline") {
@@ -136,7 +138,7 @@ function minify(files, options) {
                 if (options.sourceMap.includeSources) {
                     if (files instanceof AST_Toplevel) {
                         throw new Error("original source content unavailable");
-                    } else for (var name in files) {
+                    } else for (var name in files) if (HOP(files, name)) {
                         options.output.source_map.get().setSourceContent(name, files[name]);
                     }
                 }

lib/output.js

@@ -73,6 +73,7 @@ function OutputStream(options) {
         shebang          : true,
         shorthand        : undefined,
         source_map       : null,
+        webkit           : false,
         width            : 80,
         wrap_iife        : false,
     }, true);
@@ -532,6 +533,7 @@ function OutputStream(options) {
             use_asm = prev_use_asm;
         }
     });
+    AST_Node.DEFMETHOD("_print", AST_Node.prototype.print);
 
     AST_Node.DEFMETHOD("print_to_string", function(options){
         var s = OutputStream(options);
@@ -629,6 +631,13 @@ function OutputStream(options) {
             return true;
         }
 
+        if (output.option('webkit')) {
+            var p = output.parent();
+            if (p instanceof AST_PropAccess && p.expression === this) {
+                return true;
+            }
+        }
+
         if (output.option('wrap_iife')) {
             var p = output.parent();
             return p instanceof AST_Call && p.expression === this;
@@ -642,6 +651,10 @@ function OutputStream(options) {
         return p instanceof AST_PropAccess && p.expression === this;
     });
 
+    PARENS(AST_ClassExpression, function(output){
+        return output.parent() instanceof AST_SimpleStatement;
+    });
+
     // same goes for an object literal, because otherwise it would be
     // interpreted as a block of code.
     PARENS(AST_Object, function(output){
@@ -805,17 +818,15 @@ function OutputStream(options) {
 
     DEFPRINT(AST_Destructuring, function (self, output) {
         output.print(self.is_array ? "[" : "{");
-        var first = true;
         var len = self.names.length;
         self.names.forEach(function (name, i) {
-            if (first) first = false; else { output.comma(); output.space(); }
+            if (i > 0) output.comma();
             name.print(output);
             // If the final element is a hole, we need to make sure it
             // doesn't look like a trailing comma, by inserting an actual
             // trailing comma.
-            if (i === len - 1 && name instanceof AST_Hole)
-              output.comma();
-        })
+            if (i == len - 1 && name instanceof AST_Hole) output.comma();
+        });
         output.print(self.is_array ? "]" : "}");
     });
 
@@ -968,8 +979,12 @@ function OutputStream(options) {
     AST_Lambda.DEFMETHOD("_do_print", function(output, nokeyword){
         var self = this;
         if (!nokeyword) {
+            if (self.async) {
+                output.print("async");
+                output.space();
+            }
             output.print("function");
-            if (this.is_generator) {
+            if (self.is_generator) {
                 output.star();
             }
             if (self.name) {
@@ -1024,6 +1039,10 @@ function OutputStream(options) {
         var needs_parens = parent instanceof AST_Binary ||
             parent instanceof AST_Unary ||
             (parent instanceof AST_Call && self === parent.expression);
+        if (self.async) {
+            output.print("async");
+            output.space();
+        }
         if (needs_parens) { output.print("(") }
         if (self.argnames.length === 1 && self.argnames[0] instanceof AST_Symbol) {
             self.argnames[0].print(output);
@@ -1039,9 +1058,9 @@ function OutputStream(options) {
         output.print('=>');
         output.space();
         if (self.body instanceof AST_Node) {
-            this.body.print(output);
+            self.body.print(output);
         } else {
-            print_bracketed(this.body, output);
+            print_bracketed(self.body, output);
         }
         if (needs_parens) { output.print(")") }
     });
@@ -1073,6 +1092,22 @@ function OutputStream(options) {
         }
     });
 
+    DEFPRINT(AST_Await, function(self, output){
+        output.print("await");
+        output.space();
+        var e = self.expression;
+        var parens = !(
+               e instanceof AST_Call
+            || e instanceof AST_SymbolRef
+            || e instanceof AST_PropAccess
+            || e instanceof AST_Unary
+            || e instanceof AST_Constant
+        );
+        if (parens) output.print("(");
+        self.expression.print(output);
+        if (parens) output.print(")");
+    });
+
     /* -----[ loop control ]----- */
     AST_LoopControl.DEFMETHOD("_do_print", function(output, kind){
         output.print(kind);
@@ -1250,7 +1285,6 @@ function OutputStream(options) {
                     name_import.print(output);
                     if (i < self.imported_names.length - 1) {
                         output.print(",");
-                        output.space();
                     }
                 });
                 output.space();
@@ -1266,17 +1300,26 @@ function OutputStream(options) {
         output.semicolon();
     });
 
-    DEFPRINT(AST_NameImport, function(self, output) {
+    DEFPRINT(AST_NameMapping, function(self, output) {
+        var is_import = output.parent() instanceof AST_Import;
         var definition = self.name.definition();
         var names_are_different =
             (definition && definition.mangled_name || self.name.name) !==
             self.foreign_name.name;
         if (names_are_different) {
-            output.print(self.foreign_name.name);
+            if (is_import) {
+                output.print(self.foreign_name.name);
+            } else {
+                self.name.print(output);
+            }
             output.space();
             output.print("as");
             output.space();
-            self.name.print(output);
+            if (is_import) {
+                self.name.print(output);
+            } else {
+                output.print(self.foreign_name.name);
+            }
         } else {
             self.name.print(output);
         }
@@ -1290,24 +1333,20 @@ function OutputStream(options) {
             output.space();
         }
         if (self.exported_names) {
-            output.space();
-
             if (self.exported_names.length === 1 && self.exported_names[0].name.name === "*") {
                 self.exported_names[0].print(output);
             } else {
                 output.print("{");
-                self.exported_names.forEach(function (name_import, i) {
+                self.exported_names.forEach(function(name_export, i) {
                     output.space();
-                    name_import.print(output);
+                    name_export.print(output);
                     if (i < self.exported_names.length - 1) {
                         output.print(",");
-                        output.space();
                     }
                 });
                 output.space();
                 output.print("}");
             }
-            output.space();
         }
         else if (self.exported_value) {
             self.exported_value.print(output);
@@ -1536,7 +1575,8 @@ function OutputStream(options) {
     DEFPRINT(AST_NewTarget, function(self, output) {
         output.print("new.target");
     });
-    AST_ObjectProperty.DEFMETHOD("print_property_name", function(key, quote, output) {
+
+    function print_property_name(key, quote, output) {
         if (output.option("quote_keys")) {
             output.print_string(key + "");
         } else if ((typeof key == "number"
@@ -1553,7 +1593,8 @@ function OutputStream(options) {
         } else {
             output.print_string(key, quote);
         }
-    });
+    }
+
     DEFPRINT(AST_ObjectKeyVal, function(self, output){
         function get_name(self) {
             var def = self.definition();
@@ -1566,7 +1607,7 @@ function OutputStream(options) {
             is_identifier_string(self.key) &&
             get_name(self.value) === self.key
         ) {
-            self.print_property_name(self.key, self.quote, output);
+            print_property_name(self.key, self.quote, output);
 
         } else if (allowShortHand &&
             self.value instanceof AST_DefaultAssign &&
@@ -1574,12 +1615,14 @@ function OutputStream(options) {
             is_identifier_string(self.key) &&
             get_name(self.value.left) === self.key
         ) {
-            self.print_property_name(self.key, self.quote, output);
+            print_property_name(self.key, self.quote, output);
+            output.space();
             output.print("=");
+            output.space();
             self.value.right.print(output);
         } else {
             if (!(self.key instanceof AST_Node)) {
-                self.print_property_name(self.key, self.quote, output);
+                print_property_name(self.key, self.quote, output);
             } else {
                 output.with_square(function() {
                     self.key.print(output);
@@ -1589,15 +1632,18 @@ function OutputStream(options) {
             self.value.print(output);
         }
     });
-    AST_ObjectProperty.DEFMETHOD("_print_getter_setter", function(type, self, output) {
+    AST_ObjectProperty.DEFMETHOD("_print_getter_setter", function(type, output) {
+        var self = this;
         if (self.static) {
             output.print("static");
             output.space();
         }
-        output.print(type);
-        output.space();
+        if (type) {
+            output.print(type);
+            output.space();
+        }
         if (self.key instanceof AST_SymbolMethod) {
-            self.print_property_name(self.key.name, self.quote, output);
+            print_property_name(self.key.name, self.quote, output);
         } else {
             output.with_square(function() {
                 self.key.print(output);
@@ -1606,27 +1652,13 @@ function OutputStream(options) {
         self.value._do_print(output, true);
     });
     DEFPRINT(AST_ObjectSetter, function(self, output){
-        self._print_getter_setter("set", self, output);
+        self._print_getter_setter("set", output);
     });
     DEFPRINT(AST_ObjectGetter, function(self, output){
-        self._print_getter_setter("get", self, output);
+        self._print_getter_setter("get", output);
     });
     DEFPRINT(AST_ConciseMethod, function(self, output){
-        if (self.static) {
-            output.print("static");
-            output.space();
-        }
-        if (self.is_generator) {
-            output.print("*");
-        }
-        if (self.key instanceof AST_SymbolMethod) {
-            self.print_property_name(self.key.name, self.quote, output);
-        } else {
-            output.with_square(function() {
-                self.key.print(output);
-            });
-        }
-        self.value._do_print(output, true);
+        self._print_getter_setter(self.is_generator && "*" || self.async && "async", output);
     });
     AST_Symbol.DEFMETHOD("_do_print", function(output){
         var def = this.definition();

lib/parse.js

@@ -47,7 +47,7 @@
 var KEYWORDS = 'break case catch class const continue debugger default delete do else export extends finally for function if in instanceof new return switch throw try typeof var let void while with import';
 var KEYWORDS_ATOM = 'false null true';
 var RESERVED_WORDS = 'enum implements interface package private protected public static super this ' + KEYWORDS_ATOM + " " + KEYWORDS;
-var KEYWORDS_BEFORE_EXPRESSION = 'return new delete throw else case yield';
+var KEYWORDS_BEFORE_EXPRESSION = 'return new delete throw else case yield await';
 
 KEYWORDS = makePredicate(KEYWORDS);
 RESERVED_WORDS = makePredicate(RESERVED_WORDS);
@@ -122,8 +122,6 @@ var PUNC_BEFORE_EXPRESSION = makePredicate(characters("[{(,;:"));
 
 var PUNC_CHARS = makePredicate(characters("[]{}(),;:"));
 
-var REGEXP_MODIFIERS = makePredicate(characters("gmsiy"));
-
 /* -----[ Tokenizer ]----- */
 
 // surrogate safe regexps adapted from https://github.com/mathiasbynens/unicode-8.0.0/tree/89b412d8a71ecca9ed593d9e9fa073ab64acfebe/Binary_Property
@@ -850,9 +848,7 @@ var PRECEDENCE = (function(a, ret){
     {}
 );
 
-var STATEMENTS_WITH_LABELS = array_to_hash([ "for", "do", "while", "switch" ]);
-
-var ATOMIC_START_TOKEN = array_to_hash([ "atom", "num", "string", "regexp", "name" ]);
+var ATOMIC_START_TOKEN = makePredicate([ "atom", "num", "string", "regexp", "name" ]);
 
 /* -----[ Parser ]----- */
 
@@ -860,6 +856,7 @@ function parse($TEXT, options) {
 
     options = defaults(options, {
         bare_returns   : false,
+        ecma           : 8,
         expression     : false,
         filename       : null,
         html5_comments : true,
@@ -877,6 +874,7 @@ function parse($TEXT, options) {
         prev          : null,
         peeked        : null,
         in_function   : 0,
+        in_async      : -1,
         in_generator  : -1,
         in_directives : true,
         in_loop       : 0,
@@ -947,6 +945,10 @@ function parse($TEXT, options) {
         return S.in_generator === S.in_function;
     }
 
+    function is_in_async() {
+        return S.in_async === S.in_function;
+    }
+
     function semicolon(optional) {
         if (is("punc", ";")) next();
         else if (!optional && !can_insert_semicolon()) unexpected();
@@ -1003,6 +1005,11 @@ function parse($TEXT, options) {
             return simple_statement();
 
           case "name":
+            if (S.token.value == "async" && is_token(peek(), "keyword", "function")) {
+                next();
+                next();
+                return function_(AST_Defun, false, true);
+            }
             return is_token(peek(), "punc", ":")
                 ? labeled_statement()
                 : simple_statement();
@@ -1159,6 +1166,9 @@ function parse($TEXT, options) {
             // Ecma-262, 12.1.1 Static Semantics: Early Errors
             token_error(S.prev, "Yield cannot be used as label inside generators");
         }
+        if (label.name === "await" && is_in_async()) {
+            token_error(S.prev, "await cannot be used as label inside async function");
+        }
         if (find_if(function(l){ return l.name == label.name }, S.labels)) {
             // ECMA-262, 12.12: An ECMAScript program is considered
             // syntactically incorrect if it contains a
@@ -1220,9 +1230,12 @@ function parse($TEXT, options) {
             var is_in = is("operator", "in");
             var is_of = is("name", "of");
             if (is_in || is_of) {
-                if ((init instanceof AST_Definitions) &&
-                        init.definitions.length > 1)
-                    croak("Only one variable declaration allowed in for..in loop");
+                if (init instanceof AST_Definitions) {
+                    if (init.definitions.length > 1)
+                        croak("Only one variable declaration allowed in for..in loop", init.start.line, init.start.col, init.start.pos);
+                } else if (!(is_assignable(init) || (init = to_destructuring(init)) instanceof AST_Destructuring)) {
+                    croak("Invalid left-hand side in for..in loop", init.start.line, init.start.col, init.start.pos);
+                }
                 next();
                 if (is_in) {
                     return for_in(init);
@@ -1272,30 +1285,32 @@ function parse($TEXT, options) {
         });
     };
 
-    var arrow_function = function(start, argnames) {
+    var arrow_function = function(start, argnames, is_async) {
         if (S.token.nlb) {
             croak("Unexpected newline before arrow (=>)");
         }
 
         expect_token("arrow", "=>");
 
-        var body = _function_body(is("punc", "{"));
+        var body = _function_body(is("punc", "{"), false, is_async);
 
         return new AST_Arrow({
             start    : start,
             end      : body.end,
+            async    : is_async,
             argnames : argnames,
             body     : body
         });
     };
 
-    var function_ = function(ctor, is_generator_property) {
+    var function_ = function(ctor, is_generator_property, is_async) {
+        if (is_generator_property && is_async) croak("generators cannot be async");
         var start = S.token
 
         var in_statement = ctor === AST_Defun;
         var is_generator = is("operator", "*");
         if (is_generator) {
-          next();
+            next();
         }
 
         var name = is("name") ? as_symbol(in_statement ? AST_SymbolDefun : AST_SymbolLambda) : null;
@@ -1303,11 +1318,12 @@ function parse($TEXT, options) {
             unexpected();
 
         var args = parameters();
-        var body = _function_body(true, is_generator || is_generator_property, name, args);
+        var body = _function_body(true, is_generator || is_generator_property, is_async, name, args);
         return new ctor({
             start : args.start,
             end   : body.end,
             is_generator: is_generator,
+            async : is_async,
             name  : name,
             argnames: args,
             body  : body
@@ -1374,22 +1390,20 @@ function parse($TEXT, options) {
 
     function parameters() {
         var start = S.token;
-        var first = true;
         var params = [];
         var used_parameters = track_used_binding_identifiers(true, S.input.has_directive("use strict"));
 
         expect("(");
 
         while (!is("punc", ")")) {
-            if (first) {
-                first = false;
-            } else {
-                expect(",");
-            }
-
             var param = parameter(used_parameters);
             params.push(param);
 
+            if (!is("punc", ")")) {
+                expect(",");
+                if (is("punc", ")") && options.ecma < 8) unexpected();
+            }
+
             if (param instanceof AST_Expansion) {
                 break;
             }
@@ -1605,36 +1619,54 @@ function parse($TEXT, options) {
         }
     }
 
-    function params_or_seq_() {
-        var first = true;
+    function params_or_seq_(allow_arrows, maybe_sequence) {
+        var spread_token;
+        var invalid_sequence;
+        var trailing_comma;
         var a = [];
+        expect("(");
         while (!is("punc", ")")) {
-            if (first) first = false; else expect(",");
+            if (spread_token) unexpected(spread_token);
             if (is("expand", "...")) {
-                var spread_token = S.token;
+                spread_token = S.token;
+                if (maybe_sequence) invalid_sequence = S.token;
                 next();
                 a.push(new AST_Expansion({
                     start: prev(),
                     expression: expression(),
                     end: S.token,
                 }));
-                if (!is("punc", ")")) {
-                    unexpected(spread_token);
-                }
             } else {
                 a.push(expression());
             }
+            if (!is("punc", ")")) {
+                expect(",");
+                if (is("punc", ")")) {
+                    if (options.ecma < 8) unexpected();
+                    trailing_comma = prev();
+                    if (maybe_sequence) invalid_sequence = trailing_comma;
+                }
+            }
+        }
+        expect(")");
+        if (allow_arrows && is("arrow", "=>")) {
+            if (spread_token && trailing_comma) unexpected(trailing_comma);
+        } else if (invalid_sequence) {
+            unexpected(invalid_sequence);
         }
         return a;
     }
 
-    function _function_body(block, generator, name, args) {
+    function _function_body(block, generator, is_async, name, args) {
         var loop = S.in_loop;
         var labels = S.labels;
         var current_generator = S.in_generator;
+        var current_async = S.in_async;
         ++S.in_function;
         if (generator)
             S.in_generator = S.in_function;
+        if (is_async)
+            S.in_async = S.in_function;
         if (block)
             S.in_directives = true;
         S.in_loop = 0;
@@ -1654,9 +1686,22 @@ function parse($TEXT, options) {
         S.in_loop = loop;
         S.labels = labels;
         S.in_generator = current_generator;
+        S.in_async = current_async;
         return a;
     }
 
+    function _await_expression() {
+        // Previous token must be "await" and not be interpreted as an identifier
+        if (!is_in_async()) {
+            croak("Unexpected await expression outside async function",
+                S.prev.line, S.prev.col, S.prev.pos);
+        }
+        // the await expression is parsed as a unary expression in Babel
+        return new AST_Await({
+            expression : maybe_unary(true),
+        });
+    }
+
     function _yield_expression() {
         // Previous token must be keyword yield and not be interpret as an identifier
         if (!is_in_generator()) {
@@ -1665,7 +1710,6 @@ function parse($TEXT, options) {
         }
         var star = false;
         var has_expression = true;
-        var tmp;
 
         // Attempt to get expression or star (and then the mandatory expression)
         // behind yield on the same line.
@@ -1856,7 +1900,7 @@ function parse($TEXT, options) {
         var newexp = expr_atom(false), args;
         if (is("punc", "(")) {
             next();
-            args = expr_list(")");
+            args = expr_list(")", options.ecma >= 8);
         } else {
             args = [];
         }
@@ -1872,7 +1916,6 @@ function parse($TEXT, options) {
         var tok = S.token, ret;
         switch (tok.type) {
           case "name":
-          case "keyword":
             ret = _make_symbol(AST_SymbolRef);
             break;
           case "num":
@@ -1902,13 +1945,6 @@ function parse($TEXT, options) {
                 break;
             }
             break;
-          case "operator":
-            if (!is_identifier_string(tok.value)) {
-                croak("Invalid getter/setter name: " + tok.value,
-                    tok.line, tok.col, tok.pos);
-            }
-            ret = _make_symbol(AST_SymbolRef);
-            break;
         }
         next();
         return ret;
@@ -1971,21 +2007,24 @@ function parse($TEXT, options) {
         }
     }
 
-    var expr_atom = function(allow_calls) {
+    var expr_atom = function(allow_calls, allow_arrows) {
         if (is("operator", "new")) {
             return new_(allow_calls);
         }
         var start = S.token;
+        var async = is("name", "async") && as_atom_node();
         if (is("punc")) {
-            switch (start.value) {
+            switch (S.token.value) {
               case "(":
-                next();
-                var exprs = params_or_seq_();
-                expect(")");
-                if (is("arrow", "=>")) {
-                    return arrow_function(start, exprs.map(to_fun_args));
+                if (async && !allow_calls) break;
+                var exprs = params_or_seq_(allow_arrows, !async);
+                if (allow_arrows && is("arrow", "=>")) {
+                    return arrow_function(start, exprs.map(to_fun_args), !!async);
                 }
-                var ex = exprs.length == 1 ? exprs[0] : new AST_Sequence({
+                var ex = async ? new AST_Call({
+                    expression: async,
+                    args: exprs
+                }) : exprs.length == 1 ? exprs[0] : new AST_Sequence({
                     expressions: exprs
                 });
                 ex.start = start;
@@ -1994,17 +2033,27 @@ function parse($TEXT, options) {
               case "[":
                 return subscripts(array_(), allow_calls);
               case "{":
-                return subscripts(object_or_object_destructuring_(), allow_calls);
+                return subscripts(object_or_destructuring_(), allow_calls);
             }
-            unexpected();
+            if (!async) unexpected();
+        }
+        if (allow_arrows && is("name") && is_token(peek(), "arrow")) {
+            var param = new AST_SymbolFunarg({
+                name: S.token.value,
+                start: start,
+                end: start,
+            });
+            next();
+            return arrow_function(start, [param], !!async);
         }
         if (is("keyword", "function")) {
             next();
-            var func = function_(AST_Function);
+            var func = function_(AST_Function, false, !!async);
             func.start = start;
             func.end = prev();
             return subscripts(func, allow_calls);
         }
+        if (async) return subscripts(async, allow_calls);
         if (is("keyword", "class")) {
             next();
             var cls = class_(AST_ClassExpression);
@@ -2015,7 +2064,7 @@ function parse($TEXT, options) {
         if (is("template_head")) {
             return subscripts(template_string(), allow_calls);
         }
-        if (ATOMIC_START_TOKEN[S.token.type]) {
+        if (ATOMIC_START_TOKEN(S.token.type)) {
             return subscripts(as_atom_node(), allow_calls);
         }
         unexpected();
@@ -2079,11 +2128,11 @@ function parse($TEXT, options) {
         });
     });
 
-    var create_accessor = embed_tokens(function(is_generator) {
-        return function_(AST_Accessor, is_generator);
+    var create_accessor = embed_tokens(function(is_generator, is_async) {
+        return function_(AST_Accessor, is_generator, is_async);
     });
 
-    var object_or_object_destructuring_ = embed_tokens(function() {
+    var object_or_destructuring_ = embed_tokens(function object_or_destructuring_() {
         var start = S.token, first = true, a = [];
         expect("{");
         while (!is("punc", "}")) {
@@ -2196,6 +2245,7 @@ function parse($TEXT, options) {
             }
             return name;
         }
+        var is_async = false;
         var is_static = false;
         var is_generator = false;
         var property_token = start;
@@ -2204,6 +2254,11 @@ function parse($TEXT, options) {
             property_token = S.token;
             name = as_property_name();
         }
+        if (name === "async" && !is("punc", "(") && !is("punc", ",") && !is("punc", "}")) {
+            is_async = true;
+            property_token = S.token;
+            name = as_property_name();
+        }
         if (name === null) {
             is_generator = true;
             property_token = S.token;
@@ -2218,10 +2273,11 @@ function parse($TEXT, options) {
                 start       : start,
                 static      : is_static,
                 is_generator: is_generator,
+                async       : is_async,
                 key         : name,
                 quote       : name instanceof AST_SymbolMethod ?
                               property_token.quote : undefined,
-                value       : create_accessor(is_generator),
+                value       : create_accessor(is_generator, is_async),
                 end         : prev()
             });
             return node;
@@ -2269,7 +2325,7 @@ function parse($TEXT, options) {
             next();
         }
 
-        imported_names = import_names(true);
+        imported_names = map_names(true);
 
         if (imported_names || imported_name) {
             expect_token("name", "from");
@@ -2293,26 +2349,40 @@ function parse($TEXT, options) {
         });
     }
 
-    function import_name() {
+    function map_name(is_import) {
+        function make_symbol(type) {
+            return new type({
+                name: as_property_name(),
+                start: prev(),
+                end: prev()
+            });
+        }
+
+        var foreign_type = is_import ? AST_SymbolImportForeign : AST_SymbolExportForeign;
+        var type = is_import ? AST_SymbolImport : AST_SymbolExport;
         var start = S.token;
         var foreign_name;
         var name;
 
-        if (peek().value === "as" && peek().type === "name") {
-            foreign_name = as_symbol(AST_SymbolImportForeign);
+        if (is_import) {
+            foreign_name = make_symbol(foreign_type);
+        } else {
+            name = make_symbol(type);
+        }
+        if (is("name", "as")) {
             next();  // The "as" word
-        }
-        name = as_symbol(AST_SymbolImport);
-
-        if (foreign_name === undefined) {
-            foreign_name = new AST_SymbolImportForeign({
-                name: name.name,
-                start: name.start,
-                end: name.end,
-            });
+            if (is_import) {
+                name = make_symbol(type);
+            } else {
+                foreign_name = make_symbol(foreign_type);
+            }
+        } else if (is_import) {
+            name = new type(foreign_name);
+        } else {
+            foreign_name = new foreign_type(name);
         }
 
-        return new AST_NameImport({
+        return new AST_NameMapping({
             start: start,
             foreign_name: foreign_name,
             name: name,
@@ -2320,26 +2390,26 @@ function parse($TEXT, options) {
         })
     }
 
-    function import_nameAsterisk(name) {
+    function map_nameAsterisk(is_import, name) {
+        var foreign_type = is_import ? AST_SymbolImportForeign : AST_SymbolExportForeign;
+        var type = is_import ? AST_SymbolImport : AST_SymbolExport;
         var start = S.token;
         var foreign_name;
-
-
         var end = prev();
 
-        name = name || new AST_SymbolImport({
+        name = name || new type({
             name: '*',
             start: start,
             end: end,
         });
 
-        foreign_name = new AST_SymbolImportForeign({
+        foreign_name = new foreign_type({
             name: '*',
             start: start,
             end: end,
         });
 
-        return new AST_NameImport({
+        return new AST_NameMapping({
             start: start,
             foreign_name: foreign_name,
             name: name,
@@ -2347,13 +2417,13 @@ function parse($TEXT, options) {
         })
     }
 
-    function import_names(allow_as) {
+    function map_names(is_import) {
         var names;
         if (is("punc", "{")) {
             next();
             names = [];
             while (!is("punc", "}")) {
-                names.push(import_name());
+                names.push(map_name(is_import));
                 if (is("punc", ",")) {
                     next();
                 }
@@ -2362,11 +2432,11 @@ function parse($TEXT, options) {
         } else if (is("operator", "*")) {
             var name;
             next();
-            if (allow_as && is("name", "as")) {
+            if (is_import && is("name", "as")) {
                 next();  // The "as" word
                 name = as_symbol(AST_SymbolImportForeign);
             }
-            names = [import_nameAsterisk(name)];
+            names = [map_nameAsterisk(is_import, name)];
         }
         return names;
     }
@@ -2374,72 +2444,60 @@ function parse($TEXT, options) {
     function export_() {
         var start = S.token;
         var is_default;
-        var exported_value;
-        var exported_definition;
         var exported_names;
 
         if (is("keyword", "default")) {
             is_default = true;
             next();
-        } else {
-            exported_names = import_names(false);
+        } else if (exported_names = map_names(false)) {
+            if (is("name", "from")) {
+                next();
 
-            if (exported_names) {
-                if (is("name", "from")) {
-                    next();
-
-                    var mod_str = S.token;
-                    if (mod_str.type !== 'string') {
-                        unexpected();
-                    }
-                    next();
-
-                    return new AST_Export({
-                        start: start,
-                        is_default: is_default,
-                        exported_names: exported_names,
-                        module_name: new AST_String({
-                            start: mod_str,
-                            value: mod_str.value,
-                            quote: mod_str.quote,
-                            end: mod_str,
-                        }),
-                        end: prev(),
-                    });
-                } else {
-                    return new AST_Export({
-                        start: start,
-                        is_default: is_default,
-                        exported_names: exported_names,
-                        end: prev(),
-                    });
+                var mod_str = S.token;
+                if (mod_str.type !== 'string') {
+                    unexpected();
                 }
+                next();
+
+                return new AST_Export({
+                    start: start,
+                    is_default: is_default,
+                    exported_names: exported_names,
+                    module_name: new AST_String({
+                        start: mod_str,
+                        value: mod_str.value,
+                        quote: mod_str.quote,
+                        end: mod_str,
+                    }),
+                    end: prev(),
+                });
+            } else {
+                return new AST_Export({
+                    start: start,
+                    is_default: is_default,
+                    exported_names: exported_names,
+                    end: prev(),
+                });
             }
         }
 
-        var is_definition = is("keyword", "var") || is("keyword", "let") || is("keyword", "const");
-        if (is_definition) {
-            if (is_default) unexpected();
-            exported_definition = statement();
-        } else if (is("keyword", "class")) {
-            var cls = expr_atom(false);
-            if (cls.name) {
-                cls.name = new AST_SymbolDefClass(cls.name);
-                exported_definition = new AST_DefClass(cls);
-            } else {
-                exported_value = cls;
-            }
-        } else if (is("keyword", "function")) {
-            var func = expr_atom(false);
-            if (func.name) {
-                func.name = new AST_SymbolDefun(func.name);
-                exported_definition = new AST_Defun(func);
-            } else {
-                exported_value = func;
-            }
-        } else {
+        var node;
+        var exported_value;
+        var exported_definition;
+        if (is("punc", "{")
+            || is_default
+                && (is("keyword", "class") || is("keyword", "function"))
+                && is_token(peek(), "punc")) {
             exported_value = expression(false);
             semicolon();
+        } else if ((node = statement()) instanceof AST_Definitions && is_default) {
+            unexpected(node.start);
+        } else if (node instanceof AST_Definitions || node instanceof AST_Defun || node instanceof AST_DefClass) {
+            exported_definition = node;
+        } else if (node instanceof AST_SimpleStatement) {
+            exported_value = node.body;
+        } else {
+            unexpected(node.start);
         }
 
         return new AST_Export({
@@ -2565,11 +2623,9 @@ function parse($TEXT, options) {
         return expr;
     };
 
-    var call_args = embed_tokens(function call_args() {
-        var first = true;
+    var call_args = embed_tokens(function _call_args() {
         var args = [];
         while (!is("punc", ")")) {
-            if (first) first = false; else expect(",");
             if (is("expand", "...")) {
                 next();
                 args.push(new AST_Expansion({
@@ -2579,13 +2635,25 @@ function parse($TEXT, options) {
             } else {
                 args.push(expression(false));
             }
+            if (!is("punc", ")")) {
+                expect(",");
+                if (is("punc", ")") && options.ecma < 8) unexpected();
+            }
         }
         next();
         return args;
     });
 
-    var maybe_unary = function(allow_calls) {
+    var maybe_unary = function(allow_calls, allow_arrows) {
         var start = S.token;
+        if (start.type == "name" && start.value == "await") {
+            if (is_in_async()) {
+                next();
+                return _await_expression();
+            } else if (S.input.has_directive("use strict")) {
+                token_error(S.token, "Unexpected await identifier inside strict mode")
+            }
+        }
         if (is("operator") && UNARY_PREFIX(start.value)) {
             next();
             handle_regexp();
@@ -2594,8 +2662,9 @@ function parse($TEXT, options) {
             ex.end = prev();
             return ex;
         }
-        var val = expr_atom(allow_calls);
+        var val = expr_atom(allow_calls, allow_arrows);
         while (is("operator") && UNARY_POSTFIX(S.token.value) && !S.token.nlb) {
+            if (val instanceof AST_Arrow) unexpected();
             val = make_unary(AST_UnaryPostfix, S.token, val);
             val.start = start;
             val.end = S.token;
@@ -2643,7 +2712,7 @@ function parse($TEXT, options) {
     };
 
     function expr_ops(no_in) {
-        return expr_op(maybe_unary(true), 0, no_in);
+        return expr_op(maybe_unary(true, true), 0, no_in);
     };
 
     var maybe_conditional = function(no_in) {
@@ -2724,22 +2793,6 @@ function parse($TEXT, options) {
             }
         }
 
-        if (start.type == "punc" && start.value == "(" && peek().value == ")") {
-            next();
-            next();
-            return arrow_function(start, []);
-        }
-
-        if (is("name") && is_token(peek(), "arrow")) {
-            var param = new AST_SymbolFunarg({
-                name: start.value,
-                start: start,
-                end: start,
-            });
-            next();
-            return arrow_function(start, [param]);
-        }
-
         var left = maybe_conditional(no_in);
         var val = S.token.value;
 

lib/propmangle.js

@@ -96,7 +96,8 @@ function mangle_properties(ast, options) {
         reserved: null,
     });
 
-    var reserved = options.reserved || [];
+    var reserved = options.reserved;
+    if (!Array.isArray(reserved)) reserved = [];
     if (!options.builtins) find_builtins(reserved);
 
     var cache = options.cache;

lib/scope.js

@@ -85,7 +85,7 @@ SymbolDef.prototype = {
             if (options.ie8 && sym instanceof AST_SymbolLambda)
                 s = s.parent_scope;
             var def;
-            if (this.defun && (def = this.defun.variables.get(this.name))) {
+            if (def = this.redefined()) {
                 this.mangled_name = def.mangled_name || def.name;
             } else
                 this.mangled_name = s.next_mangled(options, this);
@@ -93,6 +93,9 @@ SymbolDef.prototype = {
                 cache.set(this.name, this.mangled_name);
             }
         }
+    },
+    redefined: function() {
+        return this.defun && this.defun.variables.get(this.name);
     }
 };
 
@@ -129,7 +132,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
             scope = save_scope;
             return true;
         }
-        if (node instanceof AST_Destructuring && node.is_array === false) {
+        if (node instanceof AST_Destructuring) {
             in_destructuring = node;  // These don't nest
             descend();
             in_destructuring = null;
@@ -223,10 +226,25 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
             }));
             node.thedef = sym;
         }
+        if (!(scope instanceof AST_Toplevel) && (node instanceof AST_Export || node instanceof AST_Import)) {
+            js_error(
+                node.TYPE + " statement may only appear at top level",
+                node.start.file,
+                node.start.line,
+                node.start.col,
+                node.start.pos
+            );
+        }
 
         function mark_export(def, level) {
+            if (in_destructuring) {
+                var i = 0;
+                do {
+                    level++;
+                } while (tw.parent(i++) !== in_destructuring);
+            }
             var node = tw.parent(level);
-            def.export = node instanceof AST_Export && !node.is_default;
+            def.export = node instanceof AST_Export;
         }
     });
     self.walk(tw);
@@ -245,17 +263,27 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
                     s.uses_eval = true;
                 }
             }
-            var sym = node.scope.find_variable(name);
-            if (node.scope instanceof AST_Lambda && name == "arguments") {
-                node.scope.uses_arguments = true;
-            }
-            if (!sym) {
+            var sym;
+            if (tw.parent() instanceof AST_NameMapping && tw.parent(1).module_name
+                || !(sym = node.scope.find_variable(name))) {
                 sym = self.def_global(node);
+            } else if (sym.scope instanceof AST_Lambda && name == "arguments") {
+                sym.scope.uses_arguments = true;
             }
             node.thedef = sym;
             node.reference(options);
             return true;
         }
+        // ensure mangling works if catch reuses a scope variable
+        var def;
+        if (node instanceof AST_SymbolCatch && (def = node.definition().redefined())) {
+            var s = node.scope;
+            while (s) {
+                push_uniq(s.enclosed, def);
+                if (s === def.scope) break;
+                s = s.parent_scope;
+            }
+        }
     });
     self.walk(tw);
 
@@ -422,7 +450,7 @@ AST_Function.DEFMETHOD("next_mangled", function(options, def){
 
 AST_Symbol.DEFMETHOD("unmangleable", function(options){
     var def = this.definition();
-    return def && def.unmangleable(options);
+    return !def || def.unmangleable(options);
 });
 
 // labels are always mangleable
@@ -450,7 +478,7 @@ AST_Symbol.DEFMETHOD("global", function(){
 });
 
 AST_Toplevel.DEFMETHOD("_default_mangler_options", function(options){
-    return defaults(options, {
+    options = defaults(options, {
         eval        : false,
         ie8         : false,
         keep_classnames: false,
@@ -458,6 +486,8 @@ AST_Toplevel.DEFMETHOD("_default_mangler_options", function(options){
         reserved    : [],
         toplevel    : false,
     });
+    if (!Array.isArray(options.reserved)) options.reserved = [];
+    return options;
 });
 
 AST_Toplevel.DEFMETHOD("mangle_names", function(options){
@@ -525,111 +555,69 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options){
 
 AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options){
     options = this._default_mangler_options(options);
-    var tw = new TreeWalker(function(node){
-        if (node instanceof AST_Constant)
-            base54.consider(node.print_to_string());
-        else if (node instanceof AST_Return)
-            base54.consider("return");
-        else if (node instanceof AST_Throw)
-            base54.consider("throw");
-        else if (node instanceof AST_Continue)
-            base54.consider("continue");
-        else if (node instanceof AST_Break)
-            base54.consider("break");
-        else if (node instanceof AST_Debugger)
-            base54.consider("debugger");
-        else if (node instanceof AST_Directive)
-            base54.consider(node.value);
-        else if (node instanceof AST_While)
-            base54.consider("while");
-        else if (node instanceof AST_Do)
-            base54.consider("do while");
-        else if (node instanceof AST_If) {
-            base54.consider("if");
-            if (node.alternative) base54.consider("else");
-        }
-        else if (node instanceof AST_Var)
-            base54.consider("var");
-        else if (node instanceof AST_Const)
-            base54.consider("const");
-        else if (node instanceof AST_Lambda)
-            base54.consider("function");
-        else if (node instanceof AST_For)
-            base54.consider("for");
-        else if (node instanceof AST_ForIn)
-            base54.consider("for in");
-        else if (node instanceof AST_Switch)
-            base54.consider("switch");
-        else if (node instanceof AST_Case)
-            base54.consider("case");
-        else if (node instanceof AST_Default)
-            base54.consider("default");
-        else if (node instanceof AST_With)
-            base54.consider("with");
-        else if (node instanceof AST_ObjectSetter)
-            base54.consider("set" + (typeof node.key === "string" ? node.key : ""));
-        else if (node instanceof AST_ObjectGetter)
-            base54.consider("get" + (typeof node.key === "string" ? node.key : ""));
-        else if (node instanceof AST_ObjectKeyVal && typeof node.key === "string")
-            base54.consider(node.key);
-        else if (node instanceof AST_ConciseMethod && typeof node.key === "string")
-            base54.consider(node.key);
-        else if (node instanceof AST_New)
-            base54.consider("new");
-        else if (node instanceof AST_This)
-            base54.consider("this");
-        else if (node instanceof AST_Super)
-            base54.consider("super");
-        else if (node instanceof AST_Try)
-            base54.consider("try");
-        else if (node instanceof AST_Catch)
-            base54.consider("catch");
-        else if (node instanceof AST_Finally)
-            base54.consider("finally");
-        else if (node instanceof AST_Yield)
-            base54.consider("yield");
-        else if (node instanceof AST_Symbol && node.unmangleable(options))
-            base54.consider(node.name);
-        else if (node instanceof AST_Unary || node instanceof AST_Binary)
-            base54.consider(node.operator);
-        else if (node instanceof AST_Dot)
-            base54.consider(node.property);
-    });
-    this.walk(tw);
+    try {
+        AST_Node.prototype.print = function(stream, force_parens) {
+            this._print(stream, force_parens);
+            if (this instanceof AST_Symbol && !this.unmangleable(options)) {
+                base54.consider(this.name, -1);
+            } else if (options.properties) {
+                if (this instanceof AST_Dot) {
+                    base54.consider(this.property, -1);
+                } else if (this instanceof AST_Sub) {
+                    skip_string(this.property);
+                }
+            }
+        };
+        base54.consider(this.print_to_string(), 1);
+    } finally {
+        AST_Node.prototype.print = AST_Node.prototype._print;
+    }
     base54.sort();
+
+    function skip_string(node) {
+        if (node instanceof AST_String) {
+            base54.consider(node.value, -1);
+        } else if (node instanceof AST_Conditional) {
+            skip_string(node.consequent);
+            skip_string(node.alternative);
+        } else if (node instanceof AST_Sequence) {
+            skip_string(node.expressions[node.expressions.length - 1]);
+        }
+    }
 });
 
 var base54 = (function() {
-    var string = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_0123456789";
+    var leading = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_".split("");
+    var digits = "0123456789".split("");
     var chars, frequency;
     function reset() {
         frequency = Object.create(null);
-        chars = string.split("").map(function(ch){ return ch.charCodeAt(0) });
-        chars.forEach(function(ch){ frequency[ch] = 0 });
+        leading.forEach(function(ch) {
+            frequency[ch] = 0;
+        });
+        digits.forEach(function(ch) {
+            frequency[ch] = 0;
+        });
     }
-    base54.consider = function(str){
+    base54.consider = function(str, delta) {
         for (var i = str.length; --i >= 0;) {
-            var code = str.charCodeAt(i);
-            if (code in frequency) ++frequency[code];
+            frequency[str[i]] += delta;
         }
     };
+    function compare(a, b) {
+        return frequency[b] - frequency[a];
+    }
     base54.sort = function() {
-        chars = mergeSort(chars, function(a, b){
-            if (is_digit(a) && !is_digit(b)) return 1;
-            if (is_digit(b) && !is_digit(a)) return -1;
-            return frequency[b] - frequency[a];
-        });
+        chars = mergeSort(leading, compare).concat(mergeSort(digits, compare));
     };
     base54.reset = reset;
     reset();
-    base54.get = function(){ return chars };
-    base54.freq = function(){ return frequency };
     function base54(num) {
         var ret = "", base = 54;
         num++;
         do {
             num--;
-            ret += String.fromCharCode(chars[num % base]);
+            ret += chars[num % base];
             num = Math.floor(num / base);
             base = 64;
         } while (num > 0);

lib/transform.js

@@ -199,6 +199,10 @@ TreeTransformer.prototype = new TreeWalker;
         if (self.expression) self.expression = self.expression.transform(tw);
     });
 
+    _(AST_Await, function(self, tw){
+        self.expression = self.expression.transform(tw);
+    });
+
     _(AST_Unary, function(self, tw){
         self.expression = self.expression.transform(tw);
     });
@@ -239,9 +243,22 @@ TreeTransformer.prototype = new TreeWalker;
         self.expression = self.expression.transform(tw);
     });
 
-    _(AST_Export, function(self, tw){
+    _(AST_NameMapping, function(self, tw) {
+        self.foreign_name = self.foreign_name.transform(tw);
+        self.name = self.name.transform(tw);
+    });
+
+    _(AST_Import, function(self, tw) {
+        if (self.imported_name) self.imported_name = self.imported_name.transform(tw);
+        if (self.imported_names) do_list(self.imported_names, tw);
+        self.module_name = self.module_name.transform(tw);
+    });
+
+    _(AST_Export, function(self, tw) {
         if (self.exported_definition) self.exported_definition = self.exported_definition.transform(tw);
         if (self.exported_value) self.exported_value = self.exported_value.transform(tw);
+        if (self.exported_names) do_list(self.exported_names, tw);
+        if (self.module_name) self.module_name = self.module_name.transform(tw);
     });
 
     _(AST_TemplateString, function(self, tw) {

lib/utils.js

@@ -43,13 +43,6 @@
 
 "use strict";
 
-function array_to_hash(a) {
-    var ret = Object.create(null);
-    for (var i = 0; i < a.length; ++i)
-        ret[a[i]] = true;
-    return ret;
-};
-
 function slice(a, start) {
     return Array.prototype.slice.call(a, start || 0);
 };

package.json

@@ -4,7 +4,7 @@
   "homepage": "https://github.com/mishoo/UglifyJS2/tree/harmony",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.0.14",
+  "version": "3.0.20",
   "engines": {
     "node": ">=0.8.0"
   },

test/benchmark.js

@@ -4,6 +4,7 @@
 "use strict";
 
 var createHash = require("crypto").createHash;
+var fetch = require("./fetch");
 var fork = require("child_process").fork;
 var args = process.argv.slice(2);
 if (!args.length) {
@@ -52,7 +53,8 @@ urls.forEach(function(url) {
         output: 0,
         log: ""
     };
-    require(url.slice(0, url.indexOf(":"))).get(url, function(res) {
+    fetch(url, function(err, res) {
+        if (err) throw err;
         var uglifyjs = fork("bin/uglifyjs", args, { silent: true });
         res.on("data", function(data) {
             results[url].input += data.length;

test/compress/arrow.js

@@ -135,3 +135,148 @@ arrow_with_regexp: {
         num => /\d{11,14}/.test( num )
     }
 }
+
+arrow_unused: {
+    options = {
+        toplevel: false,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        top => dog;
+        let fn = a => { console.log(a * a); };
+        let u = (x, y) => x - y + g;
+        (() => { console.log("0"); })();
+        !function(x) {
+            (() => { console.log("1"); })();
+            let unused = x => { console.log(x); };
+            let baz = e => e + e;
+            console.log(baz(x));
+        }(1);
+        fn(3);
+    }
+    expect: {
+        let fn = a => { console.log(a * a); };
+        let u = (x, y) => x - y + g;
+        (() => { console.log("0"); })();
+        !function(x) {
+            (() => { console.log("1"); })();
+            let baz = e => e + e;
+            console.log(baz(x));
+        }(1);
+        fn(3);
+    }
+    expect_stdout: [ "0", "1", "2", "9" ]
+    node_version: ">=6"
+}
+
+arrow_unused_toplevel: {
+    options = {
+        toplevel: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        top => dog;
+        let fn = a => { console.log(a * a); };
+        let u = (x, y) => x - y + g;
+        (() => { console.log("0"); })();
+        !function(x) {
+            (() => { console.log("1"); })();
+            let unused = x => { console.log(x); };
+            let baz = e => e + e;
+            console.log(baz(x));
+        }(1);
+        fn(3);
+    }
+    expect: {
+        let fn = a => { console.log(a * a); };
+        (() => { console.log("0"); })();
+        !function(x) {
+            (() => { console.log("1"); })();
+            let baz = e => e + e;
+            console.log(baz(x));
+        }(1);
+        fn(3);
+    }
+    expect_stdout: [ "0", "1", "2", "9" ]
+    node_version: ">=6"
+}
+
+no_leading_parentheses: {
+    input: {
+        (x,y) => x(y);
+        async (x,y) => await x(y);
+    }
+    expect_exact: "(x,y)=>x(y);async(x,y)=>await x(y);"
+}
+
+async_identifiers: {
+    options = {
+        arrows: true,
+        ecma: 6,
+    }
+    input: {
+        var async = function(x){ console.log("async", x); };
+        var await = function(x){ console.log("await", x); };
+        async(1);
+        await(2);
+    }
+    expect: {
+        var async = x => { console.log("async", x); };
+        var await = x => { console.log("await", x); };
+        async(1);
+        await(2);
+    }
+    expect_stdout: [
+        "async 1",
+        "await 2",
+    ]
+    node_version: ">=4"
+}
+
+async_function_expression: {
+    options = {
+        arrows: true,
+        ecma: 6,
+        evaluate: true,
+        side_effects: true,
+    }
+    input: {
+        var named = async function foo() {
+            await bar(1 + 0) + (2 + 0);
+        }
+        var anon = async function() {
+            await (1 + 0) + bar(2 + 0);
+        }
+    }
+    expect: {
+        var named = async function foo() {
+            await bar(1);
+        };
+        var anon = async () => {
+            await 1, bar(2);
+        };
+    }
+}
+
+issue_27: {
+    options = {
+        arrows: true,
+        collapse_vars: true,
+        ecma: 6,
+        unused: true,
+    }
+    input: {
+        (function(jQuery) {
+            var $;
+            $ = jQuery;
+            $("body").addClass("foo");
+        })(jQuery);
+    }
+    expect: {
+        (jQuery => {
+            jQuery("body").addClass("foo");
+        })(jQuery);
+    }
+}

test/compress/async.js

@@ -0,0 +1,254 @@
+await_precedence: {
+    input: {
+        async function f1() { await x + y; }
+        async function f2() { await (x + y); }
+    }
+    expect_exact: "async function f1(){await x+y}async function f2(){await(x+y)}"
+}
+
+async_function_declaration: {
+    options = {
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        async function f0() {}
+        async function f1() { await x + y; }
+        async function f2() { await (x + y); }
+        async function f3() { await x + await y; }
+        async function f4() { await (x + await y); }
+        async function f5() { await x; await y; }
+        async function f6() { await x, await y; }
+    }
+    expect: {
+        async function f0() {}
+        async function f1() { await x, y; }
+        async function f2() { await (x + y); }
+        async function f3() { await x, await y; }
+        async function f4() { await (x + await y); }
+        async function f5() { await x; await y; }
+        async function f6() { await x, await y; }
+    }
+}
+
+async_function_expression: {
+    options = {
+        evaluate: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var named = async function foo() {
+            await bar(1 + 0) + (2 + 0);
+        }
+        var anon = async function() {
+            await (1 + 0) + bar(2 + 0);
+        }
+    }
+    expect: {
+        var named = async function() {
+            await bar(1);
+        };
+        var anon = async function() {
+            await 1, bar(2);
+        };
+    }
+}
+
+async_class: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        class Foo {
+            async m1() {
+                return await foo(1 + 2);
+            }
+            static async m2() {
+                return await foo(3 + 4);
+            }
+        }
+    }
+    expect: {
+        class Foo {
+            async m1() {
+                return await foo(3);
+            }
+            static async m2() {
+                return await foo(7);
+            }
+        }
+    }
+}
+
+async_object_literal: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        var obj = {
+            async a() {
+                await foo(1 + 0);
+            },
+            anon: async function(){
+                await foo(2 + 0);
+            }
+        };
+    }
+    expect: {
+        var obj = {
+            async a() {
+                await foo(1);
+            },
+            anon: async function() {
+                await foo(2);
+            }
+        };
+    }
+}
+
+async_export: {
+    input: {
+        export async function run() {};
+        export default async function def() {};
+    }
+    expect: {
+        export async function run() {};
+        export default async function def() {};
+    }
+}
+
+async_inline: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        evaluate: true,
+        inline: true,
+        negate_iife: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        (async function(){ return await 3; })();
+        (async function(x){ await console.log(x); })(4);
+
+        function echo(x) { return x; }
+        echo( async function(){ return await 1; }() );
+        echo( async function(x){ await console.log(x); }(2) );
+
+        function top() { console.log("top"); }
+        top();
+
+        async function async_top() { console.log("async_top"); }
+        async_top();
+    }
+    expect: {
+        !async function(){await 3}();
+        !async function(x){await console.log(4)}();
+
+        function echo(x){return x}
+        echo(async function(){return await 1}());
+        echo(async function(x){await console.log(2)}());
+
+        console.log("top");
+
+        !async function(){console.log("async_top")}();
+    }
+    expect_stdout: [
+        "4",
+        "2",
+        "top",
+        "async_top",
+    ]
+    node_version: ">=8"
+}
+
+async_identifiers: {
+    input: {
+        var async = function(x){ console.log("async", x); };
+        var await = function(x){ console.log("await", x); };
+        async(1);
+        await(2);
+    }
+    expect: {
+        var async = function(x){ console.log("async", x); };
+        var await = function(x){ console.log("await", x); };
+        async(1);
+        await(2);
+    }
+    expect_stdout: [
+        "async 1",
+        "await 2",
+    ]
+}
+
+async_shorthand_property: {
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        function print(o) { console.log(o.async + " " + o.await); }
+        var async = "Async", await = "Await";
+
+        print({ async });
+        print({ await });
+        print({ async, await });
+        print({ await, async });
+
+        print({ async: async });
+        print({ await: await });
+        print({ async: async, await: await });
+        print({ await: await, async: async });
+    }
+    expect: {
+        function a(a) { console.log(a.async + " " + a.await); }
+        var n = "Async", c = "Await";
+
+        a({ async: n });
+        a({ await: c });
+        a({ async: n, await: c });
+        a({ await: c, async: n });
+
+        a({ async: n });
+        a({ await: c });
+        a({ async: n, await: c });
+        a({ await: c, async: n });
+    }
+    expect_stdout: [
+        "Async undefined",
+        "undefined Await",
+        "Async Await",
+        "Async Await",
+        "Async undefined",
+        "undefined Await",
+        "Async Await",
+        "Async Await",
+    ]
+    node_version: ">=4"
+}
+
+async_arrow: {
+    input: {
+        let a1 = async x => await foo(x);
+        let a2 = async () => await bar();
+        let a3 = async (x) => await baz(x);
+        let a4 = async (x, y) => { await far(x, y); }
+        let a5 = async ({x = [1], y: z = 2}) => { await wow(x, z); }
+    }
+    expect: {
+        let a1 = async x => await foo(x);
+        let a2 = async () => await bar();
+        let a3 = async (x) => await baz(x);
+        let a4 = async (x, y) => { await far(x, y); }
+        let a5 = async ({x = [1], y: z = 2}) => { await wow(x, z); }
+    }
+}
+
+async_arrow_wait: {
+    input: {
+        var a = async (x, y) => await x(y);
+    }
+    expect_exact: "var a=async(x,y)=>await x(y);"
+}

test/compress/block-scope.js

@@ -104,34 +104,36 @@ regression_block_scope_resolves: {
     };
     input: {
         (function () {
-            if(1) {
+            if (1) {
                 let x;
-                const y;
+                const y = 1;
                 class Zee {};
             }
-            if(1) {
+            if (1) {
                 let ex;
-                const why;
+                const why = 2;
                 class Zi {};
             }
-            console.log(x, y, Zee, ex, why, Zi);
+            console.log(typeof x, typeof y, typeof Zee, typeof ex, typeof why, typeof Zi);
         }());
     }
     expect: {
         (function () {
             if (1) {
-                let o;
-                const n;
-                class c {};
+                let e;
+                const o = 1;
+                class t {};
             }
             if (1) {
-                let o;
-                const n;
-                class c {};
+                let e;
+                const o = 2;
+                class t {};
             }
-            console.log(x, y, Zee, ex, why, Zi);
+            console.log(typeof x, typeof y, typeof Zee, typeof ex, typeof why, typeof Zi);
         }());
     }
+    expect_stdout: "undefined undefined undefined undefined undefined undefined"
+    node_version: ">=6"
 }
 
 switch_block_scope_mangler: {
@@ -153,25 +155,37 @@ switch_block_scope_mangler: {
                     console.log(cat);
             }
         };
+        fn(1);
+        fn(2);
+        fn(3);
     }
     expect: {
-        var fn = function(o) {
-            switch (o) {
+        var fn = function(e) {
+            switch (e) {
               case 1:
-                let e = o + 1
-                let c = o + 4;
-                console.log(e, c);
+                let l = e + 1
+                let o = e + 4;
+                console.log(l, o);
                 break;
 
               case 2:
-                let l = o + 2;
-                console.log(l);
+                let n = e + 2;
+                console.log(n);
                 break;
 
               default:
-                let a = o + 3;
-                console.log(a);
+                let c = e + 3;
+                console.log(c);
             }
         };
+        fn(1);
+        fn(2);
+        fn(3);
     }
+    expect_stdout: [
+        "2 5",
+        "4",
+        "6",
+    ]
+    node_version: ">=6"
 }

test/compress/collapse_vars.js

@@ -1146,7 +1146,7 @@ collapse_vars_constants: {
         function f3(x) {
             var b = x.prop;
             sideeffect1();
-            return b + -9;
+            return b + (function() { return -9; })();
         }
     }
 }

test/compress/destructuring.js

@@ -425,8 +425,8 @@ mangle_destructuring_decl: {
     expect: {
         function test(t) {
             let e = t.a || { e: 7, n: 8 };
-            let {t: n,  e: o,  n: s,  s: a = 9,  o: c,  r: l} = e;
-            console.log(n, o, s, a, c, l);
+            let {t: n,  e: o,  n: s,  s: l = 9,  o: a,  r: c} = e;
+            console.log(n, o, s, l, a, c);
         }
         test({ a: { t: 1, e: 2, n: 3, s: 4, o: 5, r: 6 } });
         test({});
@@ -462,15 +462,15 @@ mangle_destructuring_assign_toplevel_true: {
         test({});
     }
     expect: {
-        function n(n) {
-            let t, a, c;
-            let l = n.a || { e: 7, n: 8 };
-            ({t: o,  e,  n: s,  s: t = 9,  o: a,  r: c} = l);
-            console.log(o, e, s, t, a, c);
+        function e(e) {
+            let l, s, a;
+            let c = e.a || { e: 7, n: 8 };
+            ({t: n,  e: o,  n: t,  s: l = 9,  o: s,  r: a} = c);
+            console.log(n, o, t, l, s, a);
         }
-        let o, e, s;
-        n({ a: { t: 1, e: 2, n: 3, s: 4, o: 5, r: 6 } });
-        n({});
+        let n, o, t;
+        e({ a: { t: 1, e: 2, n: 3, s: 4, o: 5, r: 6 } });
+        e({});
     }
     expect_stdout: [
         "1 2 3 4 5 6",
@@ -504,10 +504,10 @@ mangle_destructuring_assign_toplevel_false: {
     }
     expect: {
         function test(o) {
-            let s, a, c;
-            let l = o.a || { e: 7, n: 8 };
-            ({t,  e,  n,  s = 9,  o: a,  r: c} = l);
-            console.log(t, e, n, s, a, c);
+            let s, l, a;
+            let c = o.a || { e: 7, n: 8 };
+            ({t,  e,  n,  s = 9,  o: l,  r: a} = c);
+            console.log(t, e, n, s, l, a);
         }
         let t, e, n;
         test({ a: { t: 1, e: 2, n: 3, s: 4, o: 5, r: 6 } });
@@ -588,10 +588,74 @@ arrow_func_with_destructuring_args: {
         })({bar: 5 - 0}, [, 6]);
     }
     expect: {
-        (({foo: o = 1, bar: n = 2}, [a = 3, b = 4]) => {
-            console.log(o, n, a, b);
+        (({foo: o = 1, bar: a = 2}, [b = 3, l = 4]) => {
+            console.log(o, a, b, l);
         })({bar: 5}, [, 6]);
     }
     expect_stdout: "1 5 3 6"
     node_version: ">=6"
 }
+
+issue_2044_ecma_5: {
+    beautify = {
+        beautify: false,
+        ecma: 5,
+    }
+    input: {
+        ({x : a = 1, y = 2 + b, z = 3 - c} = obj);
+    }
+    expect_exact: "({x:a=1,y:y=2+b,z:z=3-c}=obj);"
+}
+
+issue_2044_ecma_6: {
+    beautify = {
+        beautify: false,
+        ecma: 6,
+    }
+    input: {
+        ({x : a = 1, y = 2 + b, z = 3 - c} = obj);
+    }
+    expect_exact: "({x:a=1,y=2+b,z=3-c}=obj);"
+}
+
+issue_2044_ecma_5_beautify: {
+    beautify = {
+        beautify: true,
+        ecma: 5,
+    }
+    input: {
+        ({x : a = 1, y = 2 + b, z = 3 - c} = obj);
+    }
+    expect_exact: "({x: a = 1, y: y = 2 + b, z: z = 3 - c} = obj);"
+}
+
+issue_2044_ecma_6_beautify: {
+    beautify = {
+        beautify: true,
+        ecma: 6,
+    }
+    input: {
+        ({x : a = 1, y = 2 + b, z = 3 - c} = obj);
+    }
+    expect_exact: "({x: a = 1, y = 2 + b, z = 3 - c} = obj);"
+}
+
+issue_2140: {
+    options = {
+        unused: true,
+    }
+    input: {
+        !function() {
+            var t = {};
+            console.log(([t.a] = [42])[0]);
+        }();
+    }
+    expect: {
+        !function() {
+            var t = {};
+            console.log(([t.a] = [42])[0]);
+        }();
+    }
+    expect_stdout: "42"
+    node_version: ">=6"
+}

test/compress/drop-unused.js

@@ -863,12 +863,12 @@ issue_1583: {
     expect: {
         function m(t) {
             (function(e) {
-                t = (function() {
-                    return (function(a) {
-                        return a;
-                    })(function(a) {});
-                })();
-            })();
+                t = e();
+            })(function() {
+                return (function(a) {
+                    return a;
+                })(function(a) {});
+            });
         }
     }
 }
@@ -1280,3 +1280,132 @@ issue_1968: {
     expect_stdout: "5"
     node_version: ">=6"
 }
+
+issue_2063: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var a;
+        var a;
+    }
+    expect: {
+        var a;
+        var a;
+    }
+}
+
+issue_2105: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        !function(factory) {
+            factory();
+        }( function() {
+            return function(fn) {
+                fn()().prop();
+            }( function() {
+                function bar() {
+                    var quux = function() {
+                        console.log("PASS");
+                    }, foo = function() {
+                        console.log;
+                        quux();
+                    };
+                    return { prop: foo };
+                }
+                return bar;
+            } );
+        });
+    }
+    expect: {
+        !void function() {
+            var quux = function() {
+                console.log("PASS");
+            };
+            return {
+                prop: function() {
+                    console.log;
+                    quux();
+                }
+            };
+        }().prop();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_2136_1: {
+    options = {
+        inline: true,
+        unused: true,
+    }
+    input: {
+        !function(a, ...b) {
+            console.log(b);
+        }();
+    }
+    expect: {
+        !function(a, ...b) {
+            console.log(b);
+        }();
+    }
+    expect_stdout: "[]"
+    node_version: ">=6"
+}
+
+issue_2136_2: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f(x) {
+            console.log(x);
+        }
+        !function(a, ...b) {
+            f(b[0]);
+        }(1, 2, 3);
+    }
+    expect: {
+        function f(x) {
+            console.log(x);
+        }
+        f([2,3][0]);
+    }
+    expect_stdout: "2"
+    node_version: ">=6"
+}
+
+issue_2136_3: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        passes: 3,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        function f(x) {
+            console.log(x);
+        }
+        !function(a, ...b) {
+            f(b[0]);
+        }(1, 2, 3);
+    }
+    expect: {
+        console.log(2);
+    }
+    expect_stdout: "2"
+    node_version: ">=6"
+}

test/compress/evaluate.js

@@ -738,6 +738,7 @@ unsafe_prototype_function: {
 call_args: {
     options = {
         evaluate: true,
+        inline: true,
         reduce_vars: true,
     }
     input: {
@@ -758,6 +759,7 @@ call_args: {
 call_args_drop_param: {
     options = {
         evaluate: true,
+        inline: true,
         keep_fargs: false,
         reduce_vars: true,
         unused: true,
@@ -873,13 +875,15 @@ unsafe_charAt_noop: {
     input: {
         console.log(
             s.charAt(0),
-            "string".charAt(x)
+            "string".charAt(x),
+            (typeof x).charAt()
         );
     }
     expect: {
         console.log(
             s.charAt(0),
-            "string".charAt(x)
+            "string".charAt(x),
+            (typeof x)[0]
         );
     }
 }
@@ -1130,3 +1134,31 @@ issue_1964_2: {
     }
     expect_stdout: "b"
 }
+
+array_slice_index: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        console.log([1,2,3].slice(1)[1]);
+    }
+    expect: {
+        console.log(3);
+    }
+    expect_stdout: "3"
+}
+
+string_charCodeAt: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        console.log("foo".charCodeAt("bar".length));
+    }
+    expect: {
+        console.log(NaN);
+    }
+    expect_stdout: "NaN"
+}

test/compress/export.js

@@ -0,0 +1,228 @@
+issue_2038_1: {
+    options = {
+        toplevel: true,
+        unused: true,
+    }
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        export var V = 1;
+        export let L = 2;
+        export const C = 3;
+    }
+    expect: {
+        export var V = 1;
+        export let L = 2;
+        export const C = 3;
+    }
+}
+
+issue_2038_2: {
+    options = {
+        toplevel: true,
+        unused: true,
+    }
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        let LET = 1;
+        const CONST = 2;
+        var VAR = 3;
+        export { LET, CONST, VAR };
+    }
+    expect: {
+        let t = 1;
+        const e = 2;
+        var o = 3;
+        export { t as LET, e as CONST, o as VAR };
+    }
+}
+
+issue_2126: {
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        import { foo as bar, cat as dog } from "stuff";
+        console.log(bar, dog);
+        export { bar as qux };
+        export { dog };
+    }
+    expect: {
+        import { foo as o, cat as s } from "stuff";
+        console.log(o, s);
+        export { o as qux };
+        export { s as dog };
+    }
+}
+
+beautify: {
+    beautify = {
+        beautify: true,
+    }
+    input: {
+        export { A as B, C as D };
+    }
+    expect_exact: "export { A as B, C as D };"
+}
+
+issue_2131: {
+    options = {
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function no() {
+            console.log(42);
+        }
+        function go() {
+            console.log(42);
+        }
+        var X = 1, Y = 2;
+        export function main() {
+            go(X);
+        };
+    }
+    expect: {
+        function go() {
+            console.log(42);
+        }
+        var X = 1;
+        export function main() {
+            go(X);
+        };
+    }
+}
+
+issue_2129: {
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        export const { keys } = Object;
+    }
+    expect: {
+        export const { keys } = Object;
+    }
+}
+
+async_func: {
+    options = {
+        keep_fargs: false,
+        unused: true,
+    }
+    input: {
+        export async function Foo(x){};
+    }
+    expect: {
+        export async function Foo(){};
+    }
+}
+
+issue_2134_1: {
+    options = {
+        keep_fargs: false,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        export function Foo(x){};
+        Foo.prototype = {};
+    }
+    expect: {
+        export function Foo(){};
+        Foo.prototype = {};
+    }
+}
+
+issue_2134_2: {
+    options = {
+        keep_fargs: false,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        export async function Foo(x){};
+        Foo.prototype = {};
+    }
+    expect: {
+        export async function Foo(){};
+        Foo.prototype = {};
+    }
+}
+
+redirection: {
+    mangle = {
+        toplevel: true,
+    }
+    input: {
+        let foo = 1, bar = 2;
+        export { foo as delete };
+        export { bar as default };
+        export { foo as var } from "module.js";
+    }
+    expect: {
+        let e = 1, o = 2;
+        export { e as delete };
+        export { o as default };
+        export { foo as var } from "module.js";
+    }
+}
+
+keyword_invalid_1: {
+    input: {
+        export { default };
+    }
+    expect: {
+        export { default };
+    }
+}
+
+keyword_invalid_2: {
+    input: {
+        export { default as Alias };
+    }
+    expect: {
+        export { default as Alias };
+    }
+}
+
+keyword_invalid_3: {
+    input: {
+        export { default as default };
+    }
+    expect: {
+        export { default as default };
+    }
+}
+
+keyword_valid_1: {
+    input: {
+        export { default } from "module.js";
+    }
+    expect: {
+        export { default } from "module.js";
+    }
+}
+
+keyword_valid_2: {
+    input: {
+        export { default as Alias } from "module.js";
+    }
+    expect: {
+        export { default as Alias } from "module.js";
+    }
+}
+
+keyword_valid_3: {
+    input: {
+        export { default as default } from "module.js";
+    }
+    expect: {
+        export { default as default } from "module.js";
+    }
+}

test/compress/functions.js

@@ -21,6 +21,7 @@ iifes_returning_constants_keep_fargs_true: {
         join_vars     : true,
         reduce_vars   : true,
         cascade       : true,
+        inline        : true,
     }
     input: {
         (function(){ return -1.23; }());
@@ -56,6 +57,7 @@ iifes_returning_constants_keep_fargs_false: {
         join_vars     : true,
         reduce_vars   : true,
         cascade       : true,
+        inline        : true,
     }
     input: {
         (function(){ return -1.23; }());
@@ -82,6 +84,7 @@ issue_485_crashing_1530: {
         conditionals: true,
         dead_code: true,
         evaluate: true,
+        inline: true,
     }
     input: {
         (function(a) {
@@ -154,6 +157,7 @@ function_returning_constant_literal: {
         evaluate: true,
         cascade: true,
         unused: true,
+        inline: true,
     }
     input: {
         function greeter() {
@@ -261,9 +265,248 @@ issue_203: {
     }
     expect: {
         var m = {};
-        var fn = Function("a", "b", "b.exports=42");
+        var fn = Function("n", "o", "o.exports=42");
         fn(null, m, m.exports);
         console.log(m.exports);
     }
     expect_stdout: "42"
 }
+
+no_webkit: {
+    beautify = {
+        webkit: false,
+    }
+    input: {
+        console.log(function() {
+            1 + 1;
+        }.a = 1);
+    }
+    expect_exact: "console.log(function(){1+1}.a=1);"
+    expect_stdout: "1"
+}
+
+webkit: {
+    beautify = {
+        webkit: true,
+    }
+    input: {
+        console.log(function() {
+            1 + 1;
+        }.a = 1);
+    }
+    expect_exact: "console.log((function(){1+1}).a=1);"
+    expect_stdout: "1"
+}
+
+issue_2084: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        evaluate: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var c = 0;
+        !function() {
+            !function(c) {
+                c = 1 + c;
+                var c = 0;
+                function f14(a_1) {
+                    if (c = 1 + c, 0 !== 23..toString())
+                        c = 1 + c, a_1 && (a_1[0] = 0);
+                }
+                f14();
+            }(-1);
+        }();
+        console.log(c);
+    }
+    expect: {
+        var c = 0;
+        !function(c) {
+            c = 1 + c,
+            c = 1 + (c = 0),
+            0 !== 23..toString() && (c = 1 + c);
+        }(-1),
+        console.log(c);
+    }
+    expect_stdout: "0"
+}
+
+issue_2097: {
+    options = {
+        negate_iife: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            try {
+                throw 0;
+            } catch (e) {
+                console.log(arguments[0]);
+            }
+        }
+        f(1);
+    }
+    expect: {
+        !function() {
+            try {
+                throw 0;
+            } catch (e) {
+                console.log(arguments[0]);
+            }
+        }(1);
+    }
+    expect_stdout: "1"
+}
+
+issue_2101: {
+    options = {
+        inline: true,
+    }
+    input: {
+        a = {};
+        console.log(function() {
+            return function() {
+                return this.a;
+            }();
+        }() === function() {
+            return a;
+        }());
+    }
+    expect: {
+        a = {};
+        console.log(function() {
+            return this.a;
+        }() === a);
+    }
+    expect_stdout: "true"
+}
+
+inner_ref: {
+    options = {
+        inline: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            return function() {
+                return a;
+            }();
+        }(1), function(a) {
+            return function(a) {
+                return a;
+            }();
+        }(2));
+    }
+    expect: {
+        console.log(function(a) {
+            return a;
+        }(1), function(a) {
+            return a;
+        }());
+    }
+    expect_stdout: "1 undefined"
+}
+
+issue_2107: {
+    options = {
+        cascade: true,
+        collapse_vars: true,
+        inline: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var c = 0;
+        !function() {
+            c++;
+        }(c++ + new function() {
+            this.a = 0;
+            var a = (c = c + 1) + (c = 1 + c);
+            return c++ + a;
+        }());
+        console.log(c);
+    }
+    expect: {
+        var c = 0;
+        c++, new function() {
+            this.a = 0, c = 1 + (c += 1), c++;
+        }(), c++, console.log(c);
+    }
+    expect_stdout: "5"
+}
+
+issue_2114_1: {
+    options = {
+        collapse_vars: true,
+        if_return: true,
+        inline: true,
+        keep_fargs: false,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var c = 0;
+        !function(a) {
+            a = 0;
+        }([ {
+            0: c = c + 1,
+            length: c = 1 + c
+        }, typeof void function a() {
+            var b = function f1(a) {
+            }(b && (b.b += (c = c + 1, 0)));
+        }() ]);
+        console.log(c);
+    }
+    expect: {
+        var c = 0;
+        !function() {
+            0;
+        }((c += 1, c = 1 + c, function() {
+            var b = void (b && (b.b += (c += 1, 0)));
+        }()));
+        console.log(c);
+    }
+    expect_stdout: "2"
+}
+
+issue_2114_2: {
+    options = {
+        collapse_vars: true,
+        if_return: true,
+        inline: true,
+        keep_fargs: false,
+        passes: 2,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var c = 0;
+        !function(a) {
+            a = 0;
+        }([ {
+            0: c = c + 1,
+            length: c = 1 + c
+        }, typeof void function a() {
+            var b = function f1(a) {
+            }(b && (b.b += (c = c + 1, 0)));
+        }() ]);
+        console.log(c);
+    }
+    expect: {
+        var c = 0;
+        c = 1 + (c += 1), function() {
+            var b = void (b && (b.b += (c += 1, 0)));
+        }();
+        console.log(c);
+    }
+    expect_stdout: "2"
+}

test/compress/harmony.js

@@ -16,9 +16,12 @@ typeof_arrow_functions: {
         evaluate: true
     }
     input: {
-        var foo = typeof (x) => null;
+        var foo = typeof (x => null);
+        console.log(foo);
     }
-    expect_exact: "var foo=\"function\";"
+    expect_exact: "var foo=\"function\";console.log(foo);"
+    expect_stdout: "function"
+    node_version: ">=4"
 }
 
 classes: {
@@ -60,15 +63,15 @@ class_name_can_be_mangled: {
         function x() {
             class Foo {
             }
-            var class1 = Foo
-            var class2 = class Bar {}
+            var class1 = Foo;
+            var class2 = class Bar {};
         }
     }
     expect: {
         function x() {
             class a { }
-            var n = a
-            var r = class a {}
+            var s = a;
+            var c = class a {};
         }
     }
 }
@@ -287,12 +290,12 @@ import_statement_mangling: {
         Whatever();
     }
     expect: {
-        import l from "foo";
-        import e, {Food as o} from "lel";
+        import o from "foo";
+        import m, {Food as r} from "lel";
         import {What as f} from "lel";
-        l();
-        e();
         o();
+        m();
+        r();
         f();
     }
 }
@@ -466,10 +469,10 @@ issue_1898: {
     expect: {
         class Foo {
             bar() {
-                for (const n of [ 6, 5 ])
+                for (const f of [ 6, 5 ])
                     for (let r of [ 4, 3 ])
                         for (var o of [ 2, 1 ])
-                            console.log(n, r, o);
+                            console.log(f, r, o);
             }
         }
         new Foo().bar();
@@ -494,9 +497,9 @@ issue_1753: {
     expect: {
         class SomeClass {
             constructor(r) {
-                let a = [];
-                for (let s = 0; s < 6; s++)
-                    a.push({
+                let s = [];
+                for (let a = 0; a < 6; a++)
+                    s.push({
                         mainDrawNumbers: [],
                         extraDrawNumbers: []
                     });
@@ -523,9 +526,9 @@ issue_1753_disable: {
     expect: {
         class SomeClass {
             constructor(r) {
-                let a = [];
+                let s = [];
                 for (let r = 0; r < 6; r++)
-                    a.push({
+                    s.push({
                         mainDrawNumbers: [],
                         extraDrawNumbers: []
                     });
@@ -619,3 +622,76 @@ issue_2028: {
     expect_stdout: "hello"
     node_version: ">=6"
 }
+
+class_expression_statement: {
+    options = {
+        toplevel: false,
+        side_effects: false,
+        unused: false,
+    }
+    input: {
+        (class {});
+        (class NamedClassExpr {});
+        let expr = (class AnotherClassExpr {});
+        class C {}
+    }
+    expect_exact: "(class{});(class NamedClassExpr{});let expr=class AnotherClassExpr{};class C{}"
+}
+
+class_expression_statement_unused: {
+    options = {
+        toplevel: false,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        (class {});
+        (class NamedClassExpr {});
+        let expr = (class AnotherClassExpr {});
+        class C {}
+    }
+    expect_exact: "let expr=class{};class C{}"
+}
+
+class_expression_statement_unused_toplevel: {
+    options = {
+        toplevel: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        (class {});
+        (class NamedClassExpr {});
+        let expr = (class AnotherClassExpr {});
+        class C {}
+    }
+    expect_exact: ""
+}
+
+export_default_function_decl: {
+    options = {
+        toplevel: true,
+        passes: 3,
+        unused: true,
+    }
+    input: {
+        // do not drop "unused" exports
+        export default function Foo() {};
+        export function Far() {};
+    }
+    expect_exact: "export default function Foo(){};export function Far(){};"
+}
+
+export_default_class_decl: {
+    options = {
+        toplevel: true,
+        passes: 3,
+        unused: true,
+    }
+    input: {
+        // do not drop "unused" exports
+        export default class Car {};
+        export class Cab {};
+    }
+    expect_exact: "export default class Car{};export class Cab{};"
+}

test/compress/issue-1321.js

@@ -10,9 +10,9 @@ issue_1321_no_debug: {
     }
     expect: {
         var x = {};
-        x.b = 1;
-        x["a"] = 2 * x.b;
-        console.log(x.b, x["a"]);
+        x.o = 1;
+        x["a"] = 2 * x.o;
+        console.log(x.o, x["a"]);
     }
     expect_stdout: true
 }
@@ -30,9 +30,9 @@ issue_1321_debug: {
     }
     expect: {
         var x = {};
-        x.a = 1;
-        x["_$foo$_"] = 2 * x.a;
-        console.log(x.a, x["_$foo$_"]);
+        x.o = 1;
+        x["_$foo$_"] = 2 * x.o;
+        console.log(x.o, x["_$foo$_"]);
     }
     expect_stdout: true
 }
@@ -49,9 +49,9 @@ issue_1321_with_quoted: {
     }
     expect: {
         var x = {};
-        x.a = 1;
-        x["b"] = 2 * x.a;
-        console.log(x.a, x["b"]);
+        x.o = 1;
+        x["x"] = 2 * x.o;
+        console.log(x.o, x["x"]);
     }
     expect_stdout: true
 }

test/compress/issue-1466.js

@@ -33,8 +33,8 @@ same_variable_in_multiple_for_loop: {
             console.log(o, l);
             for (let o = 0; o < 2; o++) {
                 console.log(o, l);
-                let c = 2;
-                console.log(c);
+                let e = 2;
+                console.log(e);
             }
         }
     }
@@ -114,12 +114,12 @@ same_variable_in_multiple_forIn: {
     }
     expect: {
         var test = [ "a", "b", "c" ];
-        for (let o in test) {
-            console.log(o);
-            let e;
-            e = [ "e", "f", "g" ];
-            for (let o in test)
-                console.log(o);
+        for (let e in test) {
+            console.log(e);
+            let t;
+            t = [ "e", "f", "g" ];
+            for (let e in test)
+                console.log(e);
         }
     }
     expect_stdout: true
@@ -160,8 +160,8 @@ different_variable_in_multiple_for_loop: {
             console.log(o, l);
             for (let o = 0; o < 2; o++) {
                 console.log(o, l);
-                let c = 2;
-                console.log(c);
+                let e = 2;
+                console.log(e);
             }
         }
     }
@@ -241,12 +241,12 @@ different_variable_in_multiple_forIn: {
     }
     expect: {
         var test = [ "a", "b", "c" ];
-        for (let o in test) {
-            console.log(o);
-            let e;
-            e = [ "e", "f", "g" ];
-            for (let o in test)
-                console.log(o);
+        for (let e in test) {
+            console.log(e);
+            let t;
+            t = [ "e", "f", "g" ];
+            for (let e in test)
+                console.log(e);
         }
     }
     expect_stdout: true
@@ -281,10 +281,10 @@ more_variable_in_multiple_for: {
     }
     expect: {
         for (let o = 9, l = 0; l < 20; l += o) {
-            let c = o++ + l;
-            console.log(o, c, l);
-            for (let l = c, e = c * c, f = 0; f < 10; f++)
-                console.log(o, c, e, l, f);
+            let e = o++ + l;
+            console.log(o, e, l);
+            for (let l = e, t = e * e, c = 0; c < 10; c++)
+                console.log(o, e, t, l, c);
         }
     }
     expect_stdout: true

test/compress/issue-1770.js

@@ -82,7 +82,7 @@ numeric_literal: {
         '    42: 2,',
         '    "42": 3,',
         '    37: 4,',
-        '    a: 5,',
+        '    o: 5,',
         '    1e42: 6,',
         '    b: 7,',
         '    "1e+42": 8',
@@ -92,7 +92,7 @@ numeric_literal: {
         '',
         'console.log(obj[42], obj["42"]);',
         '',
-        'console.log(obj[37], obj["a"], obj[37], obj["37"]);',
+        'console.log(obj[37], obj["o"], obj[37], obj["37"]);',
         '',
         'console.log(obj[1e42], obj["b"], obj["1e+42"]);',
     ]

test/compress/issue-1787.js

@@ -1,6 +1,7 @@
 unary_prefix: {
     options = {
         evaluate: true,
+        inline: true,
         reduce_vars: true,
         unused: true,
     }

test/compress/issue-2001.js

@@ -45,7 +45,7 @@ export_default_func_1: {
     input: {
         export default function f(){};
     }
-    expect_exact: "export default function(){};"
+    expect_exact: "export default function f(){};"
 }
 
 export_default_func_2: {
@@ -58,7 +58,7 @@ export_default_func_2: {
     input: {
         export default function f(){}(1);
     }
-    expect_exact: "export default function(){};1;"
+    expect_exact: "export default function f(){};1;"
 }
 
 export_default_func_3: {
@@ -71,7 +71,7 @@ export_default_func_3: {
     input: {
         export default function f(){}(1);
     }
-    expect_exact: "export default function(){};"
+    expect_exact: "export default function f(){};"
 }
 
 export_class_1: {
@@ -121,7 +121,7 @@ export_default_class_1: {
     input: {
         export default class C {};
     }
-    expect_exact: "export default class{};"
+    expect_exact: "export default class C{};"
 }
 
 export_default_class_2: {
@@ -134,7 +134,7 @@ export_default_class_2: {
     input: {
         export default class C {}(1);
     }
-    expect_exact: "export default class{};1;"
+    expect_exact: "export default class C{};1;"
 }
 
 export_default_class_3: {
@@ -147,7 +147,7 @@ export_default_class_3: {
     input: {
         export default class C {}(1);
     }
-    expect_exact: "export default class{};"
+    expect_exact: "export default class C{};"
 }
 
 export_mangle_1: {
@@ -159,7 +159,7 @@ export_mangle_1: {
             return one - two;
         };
     }
-    expect_exact: "export function foo(n,o){return n-o};"
+    expect_exact: "export function foo(o,n){return o-n};"
 }
 
 export_mangle_2: {
@@ -171,7 +171,7 @@ export_mangle_2: {
             return one - two;
         };
     }
-    expect_exact: "export default function n(n,r){return n-r};"
+    expect_exact: "export default function foo(o,t){return o-t};"
 }
 
 export_mangle_3: {
@@ -189,7 +189,7 @@ export_mangle_3: {
             }
         };
     }
-    expect_exact: "export class C{go(n,r){return n-r+n}};"
+    expect_exact: "export class C{go(r,e){return r-e+r}};"
 }
 
 export_mangle_4: {
@@ -207,7 +207,7 @@ export_mangle_4: {
             }
         };
     }
-    expect_exact: "export default class n{go(n,r){return n-r+n}};"
+    expect_exact: "export default class C{go(e,r){return e-r+e}};"
 }
 
 export_mangle_5: {
@@ -221,7 +221,7 @@ export_mangle_5: {
             }
         };
     }
-    expect_exact: "export default{prop:function(n,r){return n-r}};"
+    expect_exact: "export default{prop:function(r,t){return r-t}};"
 }
 
 export_mangle_6: {
@@ -232,7 +232,7 @@ export_mangle_6: {
         var baz = 2;
         export let foo = 1, bar = baz;
     }
-    expect_exact: "var a=2;export let foo=1,bar=a;"
+    expect_exact: "var o=2;export let foo=1,bar=o;"
 }
 
 export_toplevel_1: {
@@ -247,7 +247,7 @@ export_toplevel_1: {
     }
     expect: {
         export function g(){};
-        export default function(){};
+        export default function h(){};
     }
 }
 
@@ -263,7 +263,7 @@ export_toplevel_2: {
     }
     expect: {
         export class B {};
-        export default class {};
+        export default class C {};
     }
 }
 

test/compress/issue-203.js

@@ -8,7 +8,7 @@ compress_new_function: {
         new Function("aa, bb", 'return aa;');
     }
     expect: {
-        Function("a", "b", "return a");
+        Function("n", "r", "return n");
     }
 }
 
@@ -27,8 +27,30 @@ compress_new_function_with_destruct: {
         new Function("[[aa]], [{bb}]", 'return aa;');
     }
     expect: {
-        Function("a", "[b]", "return a");
-        Function("a", "{bb:b}", "return a");
-        Function("[[a]]", "[{bb:b}]", 'return a');
+        Function("n", "[r]", "return n");
+        Function("n", "{bb:b}", "return n");
+        Function("[[n]]", "[{bb:b}]", "return n");
+    }
+}
+
+compress_new_function_with_destruct_arrows: {
+    options = {
+        arrows: true,
+        unsafe: true,
+        unsafe_Func: true,
+        ecma: 6
+    }
+    beautify = {
+        ecma: 6
+    }
+    input: {
+        new Function("aa, [bb]", 'return aa;');
+        new Function("aa, {bb}", 'return aa;');
+        new Function("[[aa]], [{bb}]", 'return aa;');
+    }
+    expect: {
+        Function("aa, [bb]", 'return aa;');
+        Function("aa, {bb}", 'return aa;');
+        Function("[[aa]], [{bb}]", 'return aa;');
     }
 }

test/compress/issue-281.js

@@ -0,0 +1,483 @@
+collapse_vars_constants: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f1(x) {
+            var a = 4, b = x.prop, c = 5, d = sideeffect1(), e = sideeffect2();
+            return b + (function() { return d - a * e - c; })();
+        }
+        function f2(x) {
+            var a = 4, b = x.prop, c = 5, not_used = sideeffect1(), e = sideeffect2();
+            return b + (function() { return -a * e - c; })();
+        }
+    }
+    expect: {
+        function f1(x) {
+            var b = x.prop, d = sideeffect1(), e = sideeffect2();
+            return b + (d - 4 * e - 5);
+        }
+        function f2(x) {
+            var b = x.prop;
+            sideeffect1();
+            return b + (-4 * sideeffect2() - 5);
+        }
+    }
+}
+
+modified: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        unused: true,
+    }
+    input: {
+        function f5(b) {
+            var a = function() {
+                return b;
+            }();
+            return b++ + a;
+        }
+        console.log(f5(1));
+    }
+    expect: {
+        function f5(b) {
+            var a = b;
+            return b++ + a;
+        }
+        console.log(f5(1));
+    }
+    expect_stdout: "2"
+}
+
+ref_scope: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            var a = 1, b = 2, c = 3;
+            var a = c++, b = b /= a;
+            return function() {
+                return a;
+            }() + b;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            var a = 1, b = 2, c = 3;
+            b = b /= a = c++;
+            return a + b;
+        }());
+    }
+    expect_stdout: true
+}
+
+safe_undefined: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        inline: true,
+        unsafe: false,
+        unused: true,
+    }
+    mangle = {}
+    input: {
+        var a, c;
+        console.log(function(undefined) {
+            return function() {
+                if (a)
+                    return b;
+                if (c)
+                    return d;
+            };
+        }(1)());
+    }
+    expect: {
+        var a, c;
+        console.log(a ? b : c ? d : void 0);
+    }
+    expect_stdout: true
+}
+
+negate_iife_3: {
+    options = {
+        conditionals: true,
+        expression: true,
+        inline: true,
+        negate_iife: true,
+    }
+    input: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+    }
+    expect: {
+        t ? console.log(true) : console.log(false);
+    }
+}
+
+negate_iife_3_off: {
+    options = {
+        conditionals: true,
+        expression: true,
+        inline: true,
+        negate_iife: false,
+    }
+    input: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+    }
+    expect: {
+        t ? console.log(true) : console.log(false);
+    }
+}
+
+negate_iife_4: {
+    options = {
+        conditionals: true,
+        expression: true,
+        inline: true,
+        negate_iife: true,
+        sequences: true,
+    }
+    input: {
+        (function(){ return t })() ? console.log(true) : console.log(false);
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        t ? console.log(true) : console.log(false), void console.log("something");
+    }
+}
+
+negate_iife_5: {
+    options = {
+        conditionals: true,
+        expression: true,
+        inline: true,
+        negate_iife: true,
+        sequences: true,
+    }
+    input: {
+        if ((function(){ return t })()) {
+            foo(true);
+        } else {
+            bar(false);
+        }
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        t ? foo(true) : bar(false), void console.log("something");
+    }
+}
+
+negate_iife_5_off: {
+    options = {
+        conditionals: true,
+        expression: true,
+        inline: true,
+        negate_iife: false,
+        sequences: true,
+    };
+    input: {
+        if ((function(){ return t })()) {
+            foo(true);
+        } else {
+            bar(false);
+        }
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        t ? foo(true) : bar(false), void console.log("something");
+    }
+}
+
+issue_1254_negate_iife_true: {
+    options = {
+        expression: true,
+        inline: true,
+        negate_iife: true,
+    }
+    input: {
+        (function() {
+            return function() {
+                console.log('test')
+            };
+        })()();
+    }
+    expect_exact: 'void console.log("test");'
+    expect_stdout: true
+}
+
+issue_1254_negate_iife_nested: {
+    options = {
+        expression: true,
+        inline: true,
+        negate_iife: true,
+    }
+    input: {
+        (function() {
+            return function() {
+                console.log('test')
+            };
+        })()()()()();
+    }
+    expect_exact: '(void console.log("test"))()()();'
+}
+
+negate_iife_issue_1073: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        inline: true,
+        negate_iife: true,
+        reduce_vars: true,
+        sequences: true,
+        unused: true,
+    };
+    input: {
+        new (function(a) {
+            return function Foo() {
+                this.x = a;
+                console.log(this);
+            };
+        }(7))();
+    }
+    expect: {
+        new function() {
+            this.x = 7,
+            console.log(this);
+        }();
+    }
+    expect_stdout: true
+}
+
+issue_1288_side_effects: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        inline: true,
+        negate_iife: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    };
+    input: {
+        if (w) ;
+        else {
+            (function f() {})();
+        }
+        if (!x) {
+            (function() {
+                x = {};
+            })();
+        }
+        if (y)
+            (function() {})();
+        else
+            (function(z) {
+                return z;
+            })(0);
+    }
+    expect: {
+        w;
+        x || (x = {});
+        y;
+    }
+}
+
+inner_var_for_in_1: {
+    options = {
+        evaluate: true,
+        inline: true,
+        reduce_vars: true,
+    }
+    input: {
+        function f() {
+            var a = 1, b = 2;
+            for (b in (function() {
+                return x(a, b, c);
+            })()) {
+                var c = 3, d = 4;
+                x(a, b, c, d);
+            }
+            x(a, b, c, d);
+        }
+    }
+    expect: {
+        function f() {
+            var a = 1, b = 2;
+            for (b in x(1, b, c)) {
+                var c = 3, d = 4;
+                x(1, b, c, d);
+            }
+            x(1, b, c, d);
+        }
+    }
+}
+
+issue_1595_3: {
+    options = {
+        evaluate: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function f(a) {
+            return g(a + 1);
+        })(2);
+    }
+    expect: {
+        g(3);
+    }
+}
+
+issue_1758: {
+    options = {
+        inline: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(function(c) {
+            var undefined = 42;
+            return function() {
+                c--;
+                c--, c.toString();
+                return;
+            }();
+        }());
+    }
+    expect: {
+        console.log(function(c) {
+            var undefined = 42;
+            return c--, c--, void c.toString();
+        }());
+    }
+    expect_stdout: "undefined"
+}
+wrap_iife: {
+    options = {
+        inline: true,
+        negate_iife: false,
+    }
+    beautify = {
+        wrap_iife: true,
+    }
+    input: {
+        (function() {
+            return function() {
+                console.log('test')
+            };
+        })()();
+    }
+    expect_exact: 'void console.log("test");'
+}
+
+wrap_iife_in_expression: {
+    options = {
+        inline: true,
+        negate_iife: false,
+    }
+    beautify = {
+        wrap_iife: true,
+    }
+    input: {
+        foo = (function () {
+            return bar();
+        })();
+    }
+    expect_exact: 'foo=bar();'
+}
+
+wrap_iife_in_return_call: {
+    options = {
+        inline: true,
+        negate_iife: false,
+    }
+    beautify = {
+        wrap_iife: true,
+    }
+    input: {
+        (function() {
+            return (function() {
+                console.log('test')
+            })();
+        })()();
+    }
+    expect_exact: '(void console.log("test"))();'
+}
+
+pure_annotation: {
+    options = {
+        inline: true,
+        side_effects: true,
+    }
+    input: {
+        /*@__PURE__*/(function() {
+            console.log("hello");
+        }());
+    }
+    expect_exact: ""
+}
+
+drop_fargs: {
+    options = {
+        cascade: true,
+        inline: true,
+        keep_fargs: false,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        !function(a_1) {
+            a++;
+        }(a++ + (a && a.var));
+        console.log(a);
+    }
+    expect: {
+        var a = 1;
+        !function() {
+            a++;
+        }(++a && a.var);
+        console.log(a);
+    }
+    expect_stdout: "3"
+}
+
+keep_fargs: {
+    options = {
+        cascade: true,
+        inline: true,
+        keep_fargs: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        !function(a_1) {
+            a++;
+        }(a++ + (a && a.var));
+        console.log(a);
+    }
+    expect: {
+        var a = 1;
+        !function(a_1) {
+            a++;
+        }(++a && a.var);
+        console.log(a);
+    }
+    expect_stdout: "3"
+}

test/compress/issue-747.js

@@ -1,37 +1,41 @@
 dont_reuse_prop: {
     mangle_props = {
         regex: /asd/
-    };
-
+    }
     input: {
+        "aaaaaaaaaabbbbb";
         var obj = {};
         obj.a = 123;
         obj.asd = 256;
         console.log(obj.a);
     }
     expect: {
+        "aaaaaaaaaabbbbb";
         var obj = {};
         obj.a = 123;
         obj.b = 256;
         console.log(obj.a);
     }
+    expect_stdout: "123"
 }
 
 unmangleable_props_should_always_be_reserved: {
     mangle_props = {
         regex: /asd/
-    };
-
+    }
     input: {
+        "aaaaaaaaaabbbbb";
         var obj = {};
         obj.asd = 256;
         obj.a = 123;
         console.log(obj.a);
     }
     expect: {
+        "aaaaaaaaaabbbbb";
         var obj = {};
         obj.b = 256;
         obj.a = 123;
         console.log(obj.a);
     }
-}
+    expect_stdout: "123"
+}

test/compress/negate-iife.js

@@ -22,7 +22,8 @@ negate_iife_1_off: {
 
 negate_iife_2: {
     options = {
-        negate_iife: true
+        inline: true,
+        negate_iife: true,
     };
     input: {
         (function(){ return {} })().x = 10;
@@ -32,6 +33,7 @@ negate_iife_2: {
 
 negate_iife_2_side_effects: {
     options = {
+        inline: true,
         negate_iife: true,
         side_effects: true,
     }
@@ -58,6 +60,7 @@ negate_iife_3_evaluate: {
     options = {
         conditionals: true,
         evaluate: true,
+        inline: true,
         negate_iife: true,
     }
     input: {
@@ -100,6 +103,7 @@ negate_iife_3_off_evaluate: {
     options = {
         conditionals: true,
         evaluate: true,
+        inline: true,
         negate_iife: false,
     }
     input: {

test/compress/node_version.js

@@ -1,4 +1,4 @@
-eval_let: {
+eval_let_6: {
     input: {
         eval("let a;");
         console.log();
@@ -10,3 +10,29 @@ eval_let: {
     expect_stdout: ""
     node_version: ">=6"
 }
+
+eval_let_4: {
+    input: {
+        eval("let a;");
+        console.log();
+    }
+    expect: {
+        eval("let a;");
+        console.log();
+    }
+    expect_stdout: SyntaxError("Block-scoped declarations (let, const, function, class) not yet supported outside strict mode")
+    node_version: "4"
+}
+
+eval_let_0: {
+    input: {
+        eval("let a;");
+        console.log();
+    }
+    expect: {
+        eval("let a;");
+        console.log();
+    }
+    expect_stdout: SyntaxError("Unexpected identifier")
+    node_version: "<=0.12"
+}

test/compress/object.js

@@ -105,7 +105,7 @@ getter_setter_mangler: {
             };
         }
     }
-    expect_exact: "function f(n,t){return{get:n,set:t,get g(){},set s(n){},c,a:1,m(){}}}"
+    expect_exact: "function f(t,e){return{get:t,set:e,get g(){},set s(t){},c,a:1,m(){}}}"
 }
 
 use_shorthand_opportunity: {
@@ -297,7 +297,7 @@ concise_methods_and_mangle_props: {
     expect: {
         function x() {
             obj = {
-                a() { return 1; }
+                o() { return 1; }
             }
         }
     }

test/compress/parameters.js

@@ -1,4 +1,7 @@
 arrow_functions: {
+    options = {
+        arrows: true,
+    }
     input: {
         (a) => b;  // 1 args
         (a, b) => c;  // n args
@@ -13,6 +16,9 @@ arrow_functions: {
 }
 
 arrow_return: {
+    options = {
+        arrows: true,
+    }
     input: {
         () => {};
         () => { return; };

test/compress/properties.js

@@ -135,11 +135,11 @@ mangle_properties: {
         a['run']({color: "blue", foo: "baz"});
     }
     expect: {
-        a["a"] = "bar";
-        a.b = "red";
-        x = {c: 10};
-        a.d(x.c, a.a);
-        a['d']({b: "blue", a: "baz"});
+        a["o"] = "bar";
+        a.a = "red";
+        x = {r: 10};
+        a.b(x.r, a.o);
+        a['b']({a: "blue", o: "baz"});
     }
 }
 
@@ -178,16 +178,16 @@ mangle_unquoted_properties: {
         function f1() {
             a["foo"] = "bar";
             a.color = "red";
-            a.b = 2;
-            x = {"bar": 10, c: 7};
-            a.c = 9;
+            a.o = 2;
+            x = {"bar": 10, f: 7};
+            a.f = 9;
         }
         function f2() {
             a.foo = "bar";
             a['color'] = "red";
-            x = {bar: 10, c: 7};
-            a.c = 9;
-            a.b = 3;
+            x = {bar: 10, f: 7};
+            a.f = 9;
+            a.o = 3;
         }
     }
 }
@@ -557,3 +557,105 @@ native_prototype: {
         "".indexOf.call(e, "bar");
     }
 }
+
+accessor_boolean: {
+    input: {
+        var a = 1;
+        var b = {
+            get true() {
+                return a;
+            },
+            set false(c) {
+                a = c;
+            }
+        };
+        console.log(b.true, b.false = 2, b.true);
+    }
+    expect_exact: 'var a=1;var b={get true(){return a},set false(c){a=c}};console.log(b.true,b.false=2,b.true);'
+    expect_stdout: "1 2 2"
+}
+
+accessor_get_set: {
+    input: {
+        var a = 1;
+        var b = {
+            get set() {
+                return a;
+            },
+            set get(c) {
+                a = c;
+            }
+        };
+        console.log(b.set, b.get = 2, b.set);
+    }
+    expect_exact: 'var a=1;var b={get set(){return a},set get(c){a=c}};console.log(b.set,b.get=2,b.set);'
+    expect_stdout: "1 2 2"
+}
+
+accessor_null_undefined: {
+    input: {
+        var a = 1;
+        var b = {
+            get null() {
+                return a;
+            },
+            set undefined(c) {
+                a = c;
+            }
+        };
+        console.log(b.null, b.undefined = 2, b.null);
+    }
+    expect_exact: 'var a=1;var b={get null(){return a},set undefined(c){a=c}};console.log(b.null,b.undefined=2,b.null);'
+    expect_stdout: "1 2 2"
+}
+
+accessor_number: {
+    input: {
+        var a = 1;
+        var b = {
+            get 42() {
+                return a;
+            },
+            set 42(c) {
+                a = c;
+            }
+        };
+        console.log(b[42], b[42] = 2, b[42]);
+    }
+    expect_exact: 'var a=1;var b={get 42(){return a},set 42(c){a=c}};console.log(b[42],b[42]=2,b[42]);'
+    expect_stdout: "1 2 2"
+}
+
+accessor_string: {
+    input: {
+        var a = 1;
+        var b = {
+            get "a-b"() {
+                return a;
+            },
+            set "a-b"(c) {
+                a = c;
+            }
+        };
+        console.log(b["a-b"], b["a-b"] = 2, b["a-b"]);
+    }
+    expect_exact: 'var a=1;var b={get"a-b"(){return a},set"a-b"(c){a=c}};console.log(b["a-b"],b["a-b"]=2,b["a-b"]);'
+    expect_stdout: "1 2 2"
+}
+
+accessor_this: {
+    input: {
+        var a = 1;
+        var b = {
+            get this() {
+                return a;
+            },
+            set this(c) {
+                a = c;
+            }
+        };
+        console.log(b.this, b.this = 2, b.this);
+    }
+    expect_exact: 'var a=1;var b={get this(){return a},set this(c){a=c}};console.log(b.this,b.this=2,b.this);'
+    expect_stdout: "1 2 2"
+}

test/compress/pure_getters.js

@@ -178,3 +178,210 @@ impure_getter_2: {
     }
     expect: {}
 }
+
+issue_2110_1: {
+    options = {
+        cascade: true,
+        pure_getters: "strict",
+        sequences: true,
+        side_effects: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function f() {}
+            function g() {
+                return this;
+            }
+            f.g = g;
+            return f.g();
+        }
+        console.log(typeof f());
+    }
+    expect: {
+        function f() {
+            function f() {}
+            return f.g = function() {
+                return this;
+            }, f.g();
+        }
+        console.log(typeof f());
+    }
+    expect_stdout: "function"
+}
+
+issue_2110_2: {
+    options = {
+        collapse_vars: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function f() {}
+            function g() {
+                return this;
+            }
+            f.g = g;
+            return f.g();
+        }
+        console.log(typeof f());
+    }
+    expect: {
+        function f() {
+            function f() {}
+            f.g = function() {
+                return this;
+            };
+            return f.g();
+        }
+        console.log(typeof f());
+    }
+    expect_stdout: "function"
+}
+
+set_immutable_1: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        a.foo += "";
+        if (a.foo) console.log("FAIL");
+        else console.log("PASS");
+    }
+    expect: {
+        1..foo += "";
+        if (1..foo) console.log("FAIL");
+        else console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+set_immutable_2: {
+    options = {
+        cascade: true,
+        conditionals: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 1;
+        a.foo += "";
+        if (a.foo) console.log("FAIL");
+        else console.log("PASS");
+    }
+    expect: {
+        var a = 1;
+        a.foo += "", a.foo ? console.log("FAIL") : console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+set_immutable_3: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        "use strict";
+        var a = 1;
+        a.foo += "";
+        if (a.foo) console.log("FAIL");
+        else console.log("PASS");
+    }
+    expect: {
+        "use strict";
+        1..foo += "";
+        if (1..foo) console.log("FAIL");
+        else console.log("PASS");
+    }
+    expect_stdout: true
+}
+
+set_immutable_4: {
+    options = {
+        cascade: true,
+        conditionals: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        toplevel: true,
+    }
+    input: {
+        "use strict";
+        var a = 1;
+        a.foo += "";
+        if (a.foo) console.log("FAIL");
+        else console.log("PASS");
+    }
+    expect: {
+        "use strict";
+        var a = 1;
+        a.foo += "", a.foo ? console.log("FAIL") : console.log("PASS");
+    }
+    expect_stdout: true
+}
+
+set_mutable_1: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        !function a() {
+            a.foo += "";
+            if (a.foo) console.log("PASS");
+            else console.log("FAIL");
+        }();
+    }
+    expect: {
+        !function a() {
+            if (a.foo += "") console.log("PASS");
+            else console.log("FAIL");
+        }();
+    }
+    expect_stdout: "PASS"
+}
+
+set_mutable_2: {
+    options = {
+        cascade: true,
+        conditionals: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        !function a() {
+            a.foo += "";
+            if (a.foo) console.log("PASS");
+            else console.log("FAIL");
+        }();
+    }
+    expect: {
+        !function a() {
+            (a.foo += "") ? console.log("PASS") : console.log("FAIL");
+        }();
+    }
+    expect_stdout: "PASS"
+}

test/compress/reduce_vars.js

@@ -2,6 +2,7 @@ reduce_vars: {
     options = {
         conditionals  : true,
         evaluate      : true,
+        inline        : true,
         global_defs   : {
             C : 0
         },
@@ -1032,6 +1033,7 @@ defun_inline_2: {
 defun_inline_3: {
     options = {
         evaluate: true,
+        inline: true,
         passes: 2,
         reduce_vars: true,
         side_effects: true,
@@ -1054,6 +1056,7 @@ defun_inline_3: {
 
 defun_call: {
     options = {
+        inline: true,
         reduce_vars: true,
         unused: true,
     }
@@ -1080,6 +1083,7 @@ defun_call: {
 
 defun_redefine: {
     options = {
+        inline: true,
         reduce_vars: true,
         unused: true,
     }
@@ -1112,6 +1116,7 @@ defun_redefine: {
 
 func_inline: {
     options = {
+        inline: true,
         reduce_vars: true,
         unused: true,
     }
@@ -1138,6 +1143,7 @@ func_inline: {
 
 func_modified: {
     options = {
+        inline: true,
         reduce_vars: true,
         unused: true,
     }
@@ -1311,19 +1317,47 @@ iife_func_side_effects: {
         unused: true,
     }
     input: {
+        function x() {
+            console.log("x");
+        }
+        function y() {
+            console.log("y");
+        }
+        function z() {
+            console.log("z");
+        }
         (function(a, b, c) {
-            return b();
+            function y() {
+                console.log("FAIL");
+            }
+            return y + b();
         })(x(), function() {
             return y();
         }, z());
     }
     expect: {
+        function x() {
+            console.log("x");
+        }
+        function y() {
+            console.log("y");
+        }
+        function z() {
+            console.log("z");
+        }
         (function(a, b, c) {
             return function() {
-                return y();
-            }();
-        })(x(), 0, z());
+                console.log("FAIL");
+            } + b();
+        })(x(), function() {
+            return y();
+        }, z());
     }
+    expect_stdout: [
+        "x",
+        "z",
+        "y",
+    ]
 }
 
 issue_1595_1: {
@@ -1687,6 +1721,7 @@ redefine_arguments_1: {
 redefine_arguments_2: {
     options = {
         evaluate: true,
+        inline: true,
         keep_fargs: false,
         reduce_vars: true,
         side_effects: true,
@@ -1723,6 +1758,7 @@ redefine_arguments_2: {
 redefine_arguments_3: {
     options = {
         evaluate: true,
+        inline: true,
         keep_fargs: false,
         passes: 3,
         reduce_vars: true,
@@ -1799,6 +1835,7 @@ redefine_farg_1: {
 redefine_farg_2: {
     options = {
         evaluate: true,
+        inline: true,
         keep_fargs: false,
         reduce_vars: true,
         side_effects: true,
@@ -1835,6 +1872,7 @@ redefine_farg_2: {
 redefine_farg_3: {
     options = {
         evaluate: true,
+        inline: true,
         keep_fargs: false,
         passes: 3,
         reduce_vars: true,
@@ -2537,3 +2575,78 @@ accessor: {
     }
     expect_stdout: "1 1"
 }
+
+issue_2090_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function() {
+            var x = 1;
+            [].forEach(() => x = 2);
+            return x;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            var x = 1;
+            [].forEach(() => x = 2);
+            return x;
+        }());
+    }
+    expect_stdout: "1"
+    node_version: ">=4"
+}
+
+issue_2090_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function() {
+            var x = 1;
+            [].forEach(() => {
+                x = 2;
+            });
+            return x;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            var x = 1;
+            [].forEach(() => {
+                x = 2;
+            });
+            return x;
+        }());
+    }
+    expect_stdout: "1"
+    node_version: ">=4"
+}
+
+for_in_prop: {
+    options = {
+        reduce_vars: true,
+    }
+    input: {
+        var a = {
+            foo: function() {
+                for (this.b in [1, 2]);
+            }
+        };
+        a.foo();
+        console.log(a.b);
+    }
+    expect: {
+        var a = {
+            foo: function() {
+                for (this.b in [1, 2]);
+            }
+        };
+        a.foo();
+        console.log(a.b);
+    }
+    expect_stdout: "1"
+}

test/compress/sandbox.js

@@ -0,0 +1,14 @@
+console_log: {
+    input: {
+        console.log("%% %s");
+        console.log("%% %s", "%s");
+    }
+    expect: {
+        console.log("%% %s");
+        console.log("%% %s", "%s");
+    }
+    expect_stdout: [
+        "%% %s",
+        "% %s",
+    ]
+}

test/compress/screw-ie8.js

@@ -255,3 +255,73 @@ issue_1586_2: {
     }
     expect_exact: "function f(){try{x()}catch(c){console.log(c.message)}}"
 }
+
+issue_2120_1: {
+    mangle = {
+        ie8: false,
+    }
+    input: {
+        "aaaaaaaa";
+        var a = 1, b = "FAIL";
+        try {
+            throw 1;
+        } catch (c) {
+            try {
+                throw 0;
+            } catch (a) {
+                if (c) b = "PASS";
+            }
+        }
+        console.log(b);
+    }
+    expect: {
+        "aaaaaaaa";
+        var a = 1, b = "FAIL";
+        try {
+            throw 1;
+        } catch (t) {
+            try {
+                throw 0;
+            } catch (a) {
+                if (t) b = "PASS";
+            }
+        }
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_2120_2: {
+    mangle = {
+        ie8: true,
+    }
+    input: {
+        "aaaaaaaa";
+        var a = 1, b = "FAIL";
+        try {
+            throw 1;
+        } catch (c) {
+            try {
+                throw 0;
+            } catch (a) {
+                if (c) b = "PASS";
+            }
+        }
+        console.log(b);
+    }
+    expect: {
+        "aaaaaaaa";
+        var a = 1, b = "FAIL";
+        try {
+            throw 1;
+        } catch (c) {
+            try {
+                throw 0;
+            } catch (a) {
+                if (c) b = "PASS";
+            }
+        }
+        console.log(b);
+    }
+    expect_stdout: "PASS"
+}

test/compress/sequences.js

@@ -734,3 +734,23 @@ reassign_const: {
     }
     expect_stdout: true
 }
+
+issue_2062: {
+    options = {
+        booleans: true,
+        cascade: true,
+        conditionals: true,
+        side_effects: true,
+    }
+    input: {
+        var a = 1;
+        if ([ a || a++ + a--, a++ + a--, a && a.var ]);
+        console.log(a);
+    }
+    expect: {
+        var a = 1;
+        a || (a++, a--), a++, --a && a.var;
+        console.log(a);
+    }
+    expect_stdout: "1"
+}

test/fetch.js

@@ -0,0 +1,31 @@
+var fs = require("fs");
+var path = require("path");
+
+try {
+    fs.mkdirSync("./tmp");
+} catch (e) {
+    if (e.code != "EEXIST") throw e;
+}
+
+function local(url) {
+    return path.join("./tmp", encodeURIComponent(url));
+}
+
+function read(url) {
+    return fs.createReadStream(local(url));
+}
+
+module.exports = function(url, callback) {
+    var result = read(url);
+    result.on("error", function(e) {
+        if (e.code != "ENOENT") return callback(e);
+        require(url.slice(0, url.indexOf(":"))).get(url, function(res) {
+            if (res.statusCode !== 200) return callback(res);
+            res.pipe(fs.createWriteStream(local(url)).on("close", function() {
+                callback(null, read(url));
+            }));
+        });
+    }).on("open", function() {
+        callback(null, result);
+    });
+};

test/input/invalid/export_1.js

@@ -0,0 +1,3 @@
+{
+    export var V = 1;
+}

test/input/invalid/export_2.js

@@ -0,0 +1 @@
+export class{};

test/input/invalid/export_3.js

@@ -0,0 +1 @@
+export function(){};

test/input/invalid/for-in_1.js

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

test/input/invalid/for-in_2.js

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

test/input/invalid/import.js

@@ -0,0 +1,3 @@
+{
+    import A from "B";
+}

test/input/invalid/sequence.js

@@ -0,0 +1 @@
+(a, ...b);

test/input/issue-2082/sample.js

@@ -0,0 +1 @@
+console.log(x);

test/input/issue-2082/sample.js.map

@@ -0,0 +1 @@
+{"version": 3,"sources": ["index.js"],"mappings": ";"}

test/jetstream.js

@@ -3,7 +3,7 @@
 
 "use strict";
 
-var site = "http://browserbench.org/JetStream/";
+var site = "http://browserbench.org/JetStream";
 if (typeof phantom == "undefined") {
     // workaround for tty output truncation upon process.exit()
     [process.stdout, process.stderr].forEach(function(stream){
@@ -11,45 +11,69 @@ if (typeof phantom == "undefined") {
             stream._handle.setBlocking(true);
     });
     var args = process.argv.slice(2);
+    var debug = args.indexOf("--debug");
+    if (debug >= 0) {
+        args.splice(debug, 1);
+        debug = true;
+    } else {
+        debug = false;
+    }
     if (!args.length) {
-        args.push("-mc");
+        args.push("-mcb", "beautify=false,webkit");
     }
     args.push("--timings");
     var child_process = require("child_process");
-    try {
-        require("phantomjs-prebuilt");
-    } catch(e) {
-        child_process.execSync("npm install phantomjs-prebuilt@2.1.14");
-    }
+    var fetch = require("./fetch");
     var http = require("http");
     var server = http.createServer(function(request, response) {
         request.resume();
-        var url = decodeURIComponent(request.url.slice(1));
-        var stderr = "";
-        var uglifyjs = child_process.fork("bin/uglifyjs", args, {
-            silent: true
-        }).on("exit", function(code) {
-            console.log("uglifyjs", url.indexOf(site) == 0 ? url.slice(site.length) : url, args.join(" "));
-            console.log(stderr);
-            if (code) throw new Error("uglifyjs failed with code " + code);
-        });
-        uglifyjs.stderr.on("data", function(data) {
-            stderr += data;
-        }).setEncoding("utf8");
-        uglifyjs.stdout.pipe(response);
-        http.get(url, function(res) {
-            res.pipe(uglifyjs.stdin);
-        });
-    }).listen().on("listening", function() {
-        var phantomjs = require("phantomjs-prebuilt");
-        var program = phantomjs.exec(process.argv[1], server.address().port);
-        program.stdout.pipe(process.stdout);
-        program.stderr.pipe(process.stderr);
-        program.on("exit", function(code) {
-            server.close();
-            if (code) throw new Error("JetStream failed!");
-            console.log("JetStream completed successfully.");
+        var url = site + request.url;
+        fetch(url, function(err, res) {
+            if (err) throw err;
+            response.writeHead(200, {
+                "Content-Type": {
+                    css: "text/css",
+                    js: "application/javascript",
+                    png: "image/png"
+                }[url.slice(url.lastIndexOf(".") + 1)] || "text/html; charset=utf-8"
+            });
+            if (/\.js$/.test(url)) {
+                var stderr = "";
+                var uglifyjs = child_process.fork("bin/uglifyjs", args, {
+                    silent: true
+                }).on("exit", function(code) {
+                    console.log("uglifyjs", url.slice(site.length + 1), args.join(" "));
+                    console.log(stderr);
+                    if (code) throw new Error("uglifyjs failed with code " + code);
+                });
+                uglifyjs.stderr.on("data", function(data) {
+                    stderr += data;
+                }).setEncoding("utf8");
+                uglifyjs.stdout.pipe(response);
+                res.pipe(uglifyjs.stdin);
+            } else {
+                res.pipe(response);
+            }
         });
+    }).listen();
+    server.on("listening", function() {
+        var port = server.address().port;
+        if (debug) {
+            console.log("http://localhost:" + port + "/");
+        } else {
+            child_process.exec("npm install phantomjs-prebuilt@2.1.14 --no-save", function(error) {
+                if (error) throw error;
+                var program = require("phantomjs-prebuilt").exec(process.argv[1], port);
+                program.stdout.pipe(process.stdout);
+                program.stderr.pipe(process.stderr);
+                program.on("exit", function(code) {
+                    server.close();
+                    if (code) throw new Error("JetStream failed!");
+                    console.log("JetStream completed successfully.");
+                    process.exit(0);
+                });
+            });
+        }
     });
     server.timeout = 0;
 } else {
@@ -63,10 +87,6 @@ if (typeof phantom == "undefined") {
         phantom.exit(1);
     };
     var url = "http://localhost:" + require("system").args[1] + "/";
-    page.onResourceRequested = function(requestData, networkRequest) {
-        if (/\.js$/.test(requestData.url))
-            networkRequest.changeUrl(url + encodeURIComponent(requestData.url));
-    }
     page.onConsoleMessage = function(msg) {
         if (/Error:/i.test(msg)) {
             console.error(msg);
@@ -77,8 +97,8 @@ if (typeof phantom == "undefined") {
             phantom.exit();
         }
     };
-    page.open(site, function(status) {
-        if (status != "success") phantomjs.exit(1);
+    page.open(url, function(status) {
+        if (status != "success") phantom.exit(1);
         page.evaluate(function() {
             JetStream.switchToQuick();
             JetStream.start();

test/mocha/arrow.js

@@ -62,23 +62,20 @@ describe("Arrow functions", function() {
         }
     });
     it("Should not accept arrow functions in the middle or end of an expression", function() {
-        var tests = [
+        [
+            "0 + x => 0",
+            "0 + async x => 0",
             "typeof x => 0",
-            "0 + x => 0"
-        ];
-        var test = function(code) {
-            return function() {
+            "typeof async x => 0",
+            "typeof (x) => null",
+            "typeof async (x) => null",
+        ].forEach(function(code) {
+            assert.throws(function() {
                 uglify.parse(code);
-            }
-        }
-        var error = function(e) {
-            return e instanceof uglify.JS_Parse_Error &&
-                e.message === "Unexpected token: arrow (=>)";
-        }
-
-        for (var i = 0; i < tests.length; i++) {
-            assert.throws(test(tests[i]), error);
-        }
+            }, function(e) {
+                return e instanceof uglify.JS_Parse_Error && /^Unexpected /.test(e.message);
+            }, code);
+        });
     });
 
     it("Should parse a function containing default assignment correctly", function() {

test/mocha/cli.js

@@ -1,6 +1,7 @@
 var assert = require("assert");
 var exec = require("child_process").exec;
 var readFileSync = require("fs").readFileSync;
+var semver = require("semver");
 
 function read(path) {
     return readFileSync(path, "utf8");
@@ -9,9 +10,11 @@ function read(path) {
 describe("bin/uglifyjs", function () {
     var uglifyjscmd = '"' + process.argv[0] + '" bin/uglifyjs';
     it("should produce a functional build when using --self", function (done) {
-        this.timeout(15000);
+        this.timeout(60000);
 
-        var command = uglifyjscmd + ' --self -cm --wrap WrappedUglifyJS';
+        var command = uglifyjscmd + ' --self -mc ecma=';
+        command += semver.satisfies(process.version, ">=4") ? "6" : "5";
+        command += ',passes=3,keep_fargs=false,unsafe --wrap WrappedUglifyJS';
 
         exec(command, function (err, stdout) {
             if (err) throw err;
@@ -77,6 +80,23 @@ describe("bin/uglifyjs", function () {
             done();
         });
     });
+    it("should not consider source map file content as source map file name (issue #2082)", function (done) {
+        var command = [
+            uglifyjscmd,
+            "test/input/issue-2082/sample.js",
+            "--source-map", "content=test/input/issue-2082/sample.js.map",
+            "--source-map", "url=inline",
+        ].join(" ");
+
+        exec(command, function (err, stdout, stderr) {
+            if (err) throw err;
+
+            var stderrLines = stderr.split('\n');
+            assert.strictEqual(stderrLines[0], 'INFO: Using input source map: test/input/issue-2082/sample.js.map');
+            assert.notStrictEqual(stderrLines[1], 'INFO: Using input source map: {"version": 3,"sources": ["index.js"],"mappings": ";"}');
+            done();
+        });
+    });
     it("Should work with --keep-fnames (mangle only)", function (done) {
         var command = uglifyjscmd + ' test/input/issue-1431/sample.js --keep-fnames -m';
 
@@ -516,6 +536,111 @@ describe("bin/uglifyjs", function () {
             done();
         });
     });
+    it("Should throw syntax error (block-level export)", function(done) {
+        var command = uglifyjscmd + ' test/input/invalid/export_1.js -m';
+
+        exec(command, function (err, stdout, stderr) {
+            assert.ok(err);
+            assert.strictEqual(stdout, "");
+            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+                "Parse error at test/input/invalid/export_1.js:2,4",
+                "    export var V = 1;",
+                "    ^",
+                "ERROR: Export statement may only appear at top level"
+            ].join("\n"));
+            done();
+        });
+    });
+    it("Should throw syntax error (block-level import)", function(done) {
+        var command = uglifyjscmd + ' test/input/invalid/import.js -m';
+
+        exec(command, function (err, stdout, stderr) {
+            assert.ok(err);
+            assert.strictEqual(stdout, "");
+            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+                "Parse error at test/input/invalid/import.js:2,4",
+                '    import A from "B";',
+                "    ^",
+                "ERROR: Import statement may only appear at top level"
+            ].join("\n"));
+            done();
+        });
+    });
+    it("Should throw syntax error (anonymous class)", function(done) {
+        var command = uglifyjscmd + ' test/input/invalid/export_2.js';
+
+        exec(command, function (err, stdout, stderr) {
+            assert.ok(err);
+            assert.strictEqual(stdout, "");
+            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+                "Parse error at test/input/invalid/export_2.js:1,12",
+                "export class{};",
+                "            ^",
+                "ERROR: Unexpected token: punc ({)"
+            ].join("\n"));
+            done();
+        });
+    });
+    it("Should throw syntax error (anonymous function)", function(done) {
+        var command = uglifyjscmd + ' test/input/invalid/export_3.js';
+
+        exec(command, function (err, stdout, stderr) {
+            assert.ok(err);
+            assert.strictEqual(stdout, "");
+            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+                "Parse error at test/input/invalid/export_3.js:1,15",
+                "export function(){};",
+                "               ^",
+                "ERROR: Unexpected token: punc (()"
+            ].join("\n"));
+            done();
+        });
+    });
+    it("Should throw syntax error (spread in sequence)", function(done) {
+        var command = uglifyjscmd + ' test/input/invalid/sequence.js';
+
+        exec(command, function (err, stdout, stderr) {
+            assert.ok(err);
+            assert.strictEqual(stdout, "");
+            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+                "Parse error at test/input/invalid/sequence.js:1,4",
+                "(a, ...b);",
+                "    ^",
+                "ERROR: Unexpected token: expand (...)"
+            ].join("\n"));
+            done();
+        });
+    });
+    it("Should throw syntax error (for-in init)", function(done) {
+        var command = uglifyjscmd + ' test/input/invalid/for-in_1.js';
+
+        exec(command, function (err, stdout, stderr) {
+            assert.ok(err);
+            assert.strictEqual(stdout, "");
+            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+                "Parse error at test/input/invalid/for-in_1.js:2,5",
+                "for (1, 2, a in b) {",
+                "     ^",
+                "ERROR: Invalid left-hand side in for..in loop"
+            ].join("\n"));
+            done();
+        });
+    });
+    it("Should throw syntax error (for-in var)", function(done) {
+        var command = uglifyjscmd + ' test/input/invalid/for-in_2.js';
+
+        exec(command, function (err, stdout, stderr) {
+            assert.ok(err);
+            assert.strictEqual(stdout, "");
+            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+                "Parse error at test/input/invalid/for-in_2.js:2,5",
+                "for (var a, b in c) {",
+                "     ^",
+                "ERROR: Only one variable declaration allowed in for..in loop"
+            ].join("\n"));
+            done();
+        });
+    });
     it("Should handle literal string as source map input", function(done) {
         var command = [
             uglifyjscmd,
@@ -557,7 +682,27 @@ describe("bin/uglifyjs", function () {
         exec(command, function (err, stdout, stderr) {
             assert.ok(err);
             assert.strictEqual(stdout, "");
-            assert.ok(/^Supported options:\n\{[^}]+}\nERROR: `ascii-only` is not a supported option/.test(stderr), stderr);
+            assert.ok(/^Supported options:\n[\s\S]*?\nERROR: `ascii-only` is not a supported option/.test(stderr), stderr);
+            done();
+        });
+    });
+    it("Should work with --mangle reserved=[]", function (done) {
+        var command = uglifyjscmd + ' test/input/issue-505/input.js -m reserved=[callback]';
+
+        exec(command, function (err, stdout) {
+            if (err) throw err;
+
+            assert.strictEqual(stdout, 'function test(callback){"aaaaaaaaaaaaaaaa";callback(err,data);callback(err,data)}\n');
+            done();
+        });
+    });
+    it("Should work with --mangle reserved=false", function (done) {
+        var command = uglifyjscmd + ' test/input/issue-505/input.js -m reserved=false';
+
+        exec(command, function (err, stdout) {
+            if (err) throw err;
+
+            assert.strictEqual(stdout, 'function test(a){"aaaaaaaaaaaaaaaa";a(err,data);a(err,data)}\n');
             done();
         });
     });

test/mocha/export.js

@@ -2,8 +2,7 @@ var assert = require("assert");
 var uglify = require("../node");
 
 describe("Export", function() {
-    it ("Should parse export directives", function() {
-
+    it("Should parse export directives", function() {
         var inputs = [
             ['export * from "a.js"', ['*'], "a.js"],
             ['export {A} from "a.js"', ['A'], "a.js"],
@@ -12,17 +11,17 @@ describe("Export", function() {
             ['export {A, B} from "a.js"', ['A', 'B'], "a.js"],
         ];
 
-        var test = function(code) {
+        function test(code) {
             return uglify.parse(code);
-        };
+        }
 
-        var extractNames = function(symbols) {
+        function extractNames(symbols) {
             var ret = [];
             for (var i = 0; i < symbols.length; i++) {
-                ret.push(symbols[i].name.name)
+                ret.push(symbols[i].foreign_name.name);
             }
             return ret;
-        };
+        }
 
         for (var i = 0; i < inputs.length; i++) {
             var ast = test(inputs[i][0]);
@@ -34,7 +33,7 @@ describe("Export", function() {
             assert(st instanceof uglify.AST_Export);
             var actualNames = extractNames(st.exported_names);
             assert.deepEqual(actualNames, names);
-            assert.equal(st.module_name.value, filename)
+            assert.equal(st.module_name.value, filename);
         }
-    })
-});
+    });
+});

test/mocha/function.js

@@ -191,15 +191,51 @@ describe("Function", function() {
         ];
         var test = function(code) {
             return function() {
-                uglify.parse(code);
+                uglify.parse(code, { ecma: 5 });
             }
         }
         var error = function(e) {
-            return e instanceof uglify.JS_Parse_Error &&
-                e.message === "Invalid function parameter";
+            return e instanceof uglify.JS_Parse_Error;
         }
         for (var i = 0; i < tests.length; i++) {
-            assert.throws(test(tests[i]), error);
+            assert.throws(test(tests[i]), error, tests[i]);
+        }
+    });
+    it("Should accept trailing commas only for ES8", function() {
+        [
+            "new Foo(a, );",
+            "async(...[1, 2], );",
+            "console.log(...[1, 2], );",
+            "!function(a, b, ){ console.log(a + b); }(3, 4, );",
+        ].forEach(function(code) {
+            uglify.parse(code, { ecma: 8 });
+            assert.throws(function() {
+                uglify.parse(code, { ecma: 6 });
+            }, function(e) {
+                return e instanceof uglify.JS_Parse_Error;
+            }, code);
+        });
+    });
+    it("Should not accept invalid trailing commas", function() {
+        var tests = [
+            "f(, );",
+            "(, ) => {};",
+            "(...p, ) => {};",
+            "function f(, ) {}",
+            "function f(...p, ) {}",
+            "function foo(a, b, , ) {}",
+            'console.log("hello", , );',
+        ];
+        var test = function(code) {
+            return function() {
+                uglify.parse(code, { ecma: 8 });
+            }
+        }
+        var error = function(e) {
+            return e instanceof uglify.JS_Parse_Error;
+        }
+        for (var i = 0; i < tests.length; i++) {
+            assert.throws(test(tests[i]), error, tests[i]);
         }
     });
     it("Should not accept an initializer when parameter is a rest parameter", function() {

test/mocha/glob.js

@@ -31,7 +31,7 @@ describe("bin/uglifyjs with input file globs", function() {
         exec(command, function(err, stdout) {
             if (err) throw err;
 
-            assert.strictEqual(stdout, 'var print=console.log.bind(console),a=function(n){return 3*n}(3),b=function(n){return n/2}(12);print("qux",a,b),function(n){print("Foo:",2*n)}(11);\n');
+            assert.strictEqual(stdout, 'var print=console.log.bind(console);print("qux",9,6),print("Foo:",2*11);\n');
             done();
         });
     });

test/mocha/let.js

@@ -2,29 +2,37 @@ var Uglify = require('../../');
 var assert = require("assert");
 
 describe("let", function() {
-    it("Should not produce `let` as a variable name in mangle", function(done) {
+    it("Should not produce reserved keywords as variable name in mangle", function(done) {
         this.timeout(10000);
 
         // Produce a lot of variables in a function and run it through mangle.
-        var s = '"use strict"; function foo() {';
-        for (var i = 0; i < 21000; ++i) {
+        var s = '"dddddeeeeelllllooooottttt"; function foo() {';
+        for (var i = 0; i < 18000; i++) {
             s += "var v" + i + "=0;";
         }
         s += '}';
         var result = Uglify.minify(s, {compress: false});
 
         // Verify that select keywords and reserved keywords not produced
-        assert.strictEqual(result.code.indexOf("var let="), -1);
-        assert.strictEqual(result.code.indexOf("var do="), -1);
-        assert.strictEqual(result.code.indexOf("var var="), -1);
+        [
+            "do",
+            "let",
+            "var",
+        ].forEach(function(name) {
+            assert.strictEqual(result.code.indexOf("var " + name + "="), -1);
+        });
 
         // Verify that the variable names that appeared immediately before
-        // and after the erroneously generated `let` variable name still exist
+        // and after the erroneously generated variable name still exist
         // to show the test generated enough symbols.
-        assert(result.code.indexOf("var ket=") >= 0);
-        assert(result.code.indexOf("var met=") >= 0);
+        [
+            "to", "eo",
+            "eet", "fet",
+            "rar", "oar",
+        ].forEach(function(name) {
+            assert.ok(result.code.indexOf("var " + name + "=") >= 0);
+        });
 
         done();
     });
 });
-

test/mocha/minify.js

@@ -13,6 +13,13 @@ describe("minify", function() {
         assert.strictEqual(result.code, 'function foo(n){return n?3:7}');
     });
 
+    it("Should skip inherited keys from `files`", function() {
+        var files = Object.create({ skip: this });
+        files[0] = "alert(1 + 1)";
+        var result = Uglify.minify(files);
+        assert.strictEqual(result.code, "alert(2);");
+    });
+
     describe("keep_quoted_props", function() {
         it("Should preserve quotes in object literals", function() {
             var js = 'var foo = {"x": 1, y: 2, \'z\': 3};';
@@ -106,7 +113,7 @@ describe("minify", function() {
                         content: "inline"
                     }
                 });
-                assert.strictEqual(result.code, "var bar=function(){function foo(bar){return bar}return foo}();");
+                assert.strictEqual(result.code, "var bar=function(){return function(bar){return bar}}();");
                 assert.strictEqual(warnings.length, 1);
                 assert.strictEqual(warnings[0], "inline source map not found");
             } finally {
@@ -207,5 +214,17 @@ describe("minify", function() {
             assert.ok(err instanceof Error);
             assert.strictEqual(err.stack.split(/\n/)[0], "Error: Can't handle expression: debugger");
         });
+        it("should skip inherited properties", function() {
+            var foo = Object.create({ skip: this });
+            foo.bar = 42;
+            var result = Uglify.minify("alert(FOO);", {
+                compress: {
+                    global_defs: {
+                        FOO: foo
+                    }
+                }
+            });
+            assert.strictEqual(result.code, "alert({bar:42});");
+        });
     });
 });

test/mocha/release.js

@@ -1,23 +1,20 @@
 var assert = require("assert");
+var semver = require("semver");
 var spawn = require("child_process").spawn;
 
 if (!process.env.UGLIFYJS_TEST_ALL) return;
 
 function run(command, args, done) {
-    var id = setInterval(function() {
-        process.stdout.write("\0");
-    }, 5 * 60 * 1000);
     spawn(command, args, {
-        stdio: "ignore"
+        stdio: [ "ignore", 1, 2 ]
     }).on("exit", function(code) {
-        clearInterval(id);
         assert.strictEqual(code, 0);
         done();
     });
 }
 
 describe("test/benchmark.js", function() {
-    this.timeout(5 * 60 * 1000);
+    this.timeout(10 * 60 * 1000);
     [
         "-b",
         "-b bracketize",
@@ -36,11 +33,9 @@ describe("test/benchmark.js", function() {
     });
 });
 
+if (semver.satisfies(process.version, "0.12")) return;
 describe("test/jetstream.js", function() {
     this.timeout(20 * 60 * 1000);
-    it("Should install phantomjs-prebuilt", function(done) {
-        run("npm", ["install", "phantomjs-prebuilt@2.1.14"], done);
-    });
     [
         "-mc",
         "-mc keep_fargs=false,passes=3,pure_getters,unsafe,unsafe_comps,unsafe_math,unsafe_proto",
@@ -48,6 +43,7 @@ describe("test/jetstream.js", function() {
         it("Should pass with options " + options, function(done) {
             var args = options.split(/ /);
             args.unshift("test/jetstream.js");
+            args.push("-b", "beautify=false,webkit");
             run(process.argv[0], args, done);
         });
     });

test/mocha/spidermonkey.js

@@ -4,7 +4,7 @@ var uglify = require("../node");
 
 describe("spidermonkey export/import sanity test", function() {
     it("should produce a functional build when using --self with spidermonkey", function(done) {
-        this.timeout(30000);
+        this.timeout(60000);
 
         var uglifyjs = '"' + process.argv[0] + '" bin/uglifyjs';
         var command = uglifyjs + " --self -cm --wrap SpiderUglify -o spidermonkey | " +

test/run-tests.js

@@ -86,7 +86,6 @@ function run_compress_tests() {
         log_start_file(file);
         function test_case(test) {
             log_test(test.name);
-            U.base54.reset();
             var output_options = test.beautify || {};
             var expect;
             if (test.expect) {
@@ -101,9 +100,6 @@ function run_compress_tests() {
                 quote_style: 3,
                 keep_quoted_props: true
             });
-            if (test.mangle_props) {
-                input = U.mangle_properties(input, test.mangle_props);
-            }
             var options = U.defaults(test.options, {
                 warnings: false
             });
@@ -118,10 +114,16 @@ function run_compress_tests() {
             var cmp = new U.Compressor(options, true);
             var output = cmp.compress(input);
             output.figure_out_scope(test.mangle);
-            if (test.mangle) {
+            if (test.mangle || test.mangle_props) {
+                U.base54.reset();
                 output.compute_char_frequency(test.mangle);
+            }
+            if (test.mangle) {
                 output.mangle_names(test.mangle);
             }
+            if (test.mangle_props) {
+                output = U.mangle_properties(output, test.mangle_props);
+            }
             output = make_code(output, output_options);
             if (expect != output) {
                 log("!!! failed\n---INPUT---\n{input}\n---OUTPUT---\n{output}\n---EXPECTED---\n{expected}\n\n", {
@@ -294,8 +296,22 @@ function parse_test(file) {
                 if (label.name == "expect_exact" || label.name == "node_version") {
                     test[label.name] = read_string(stat);
                 } else if (label.name == "expect_stdout") {
-                    if (stat.TYPE == "SimpleStatement" && stat.body instanceof U.AST_Boolean) {
-                        test[label.name] = stat.body.value;
+                    var body = stat.body;
+                    if (body instanceof U.AST_Boolean) {
+                        test[label.name] = body.value;
+                    } else if (body instanceof U.AST_Call) {
+                        var ctor = global[body.expression.name];
+                        assert.ok(ctor === Error || ctor.prototype instanceof Error, tmpl("Unsupported expect_stdout format [{line},{col}]", {
+                            line: label.start.line,
+                            col: label.start.col
+                        }));
+                        test[label.name] = ctor.apply(null, body.args.map(function(node) {
+                            assert.ok(node instanceof U.AST_Constant, tmpl("Unsupported expect_stdout format [{line},{col}]", {
+                                line: label.start.line,
+                                col: label.start.col
+                            }));
+                            return node.value;
+                        }));
                     } else {
                         test[label.name] = read_string(stat) + "\n";
                     }

test/sandbox.js

@@ -19,23 +19,25 @@ function safe_log(arg, level) {
 
 var FUNC_TOSTRING = [
     "Function.prototype.toString = Function.prototype.valueOf = function() {",
-    "    var id = 0;",
+    "    var id = 100000;",
     "    return function() {",
     '        if (this === Array) return "[Function: Array]";',
     '        if (this === Object) return "[Function: Object]";',
     "        var i = this.name;",
     '        if (typeof i != "number") {',
     "            i = ++id;",
+].concat(Object.getOwnPropertyDescriptor(Function.prototype, "name").configurable ? [
     '            Object.defineProperty(this, "name", {',
     "                get: function() {",
     "                    return i;",
     "                }",
     "            });",
+] : [], [
     "        }",
     '        return "[Function: " + i + "]";',
     "    }",
     "}();",
-].join("\n");
+]).join("\n");
 exports.run_code = function(code) {
     var stdout = "";
     var original_write = process.stdout.write;
@@ -50,7 +52,10 @@ exports.run_code = function(code) {
             "}();",
         ].join("\n"), {
             console: {
-                log: function() {
+                log: function(msg) {
+                    if (arguments.length == 1 && typeof msg == "string") {
+                        return console.log("%s", msg);
+                    }
                     return console.log.apply(console, [].map.call(arguments, function(arg) {
                         return safe_log(arg, 3);
                     }));

test/ufuzz.js

@@ -102,23 +102,23 @@ for (var i = 2; i < process.argv.length; ++i) {
       case '--help':
       case '-h':
       case '-?':
-        console.log('** UglifyJS fuzzer help **');
-        console.log('Valid options (optional):');
-        console.log('<number>: generate this many cases (if used must be first arg)');
-        console.log('-v: print every generated test case');
-        console.log('-V: print every 100th generated test case');
-        console.log('-t <int>: generate this many toplevels per run (more take longer)');
-        console.log('-r <int>: maximum recursion depth for generator (higher takes longer)');
-        console.log('-s1 <statement name>: force the first level statement to be this one (see list below)');
-        console.log('-s2 <statement name>: force the second level statement to be this one (see list below)');
-        console.log('--no-catch-redef: do not redefine catch variables');
-        console.log('--no-directive: do not generate directives');
-        console.log('--use-strict: generate "use strict"');
-        console.log('--stmt-depth-from-func: reset statement depth counter at each function, counts from global otherwise');
-        console.log('--only-stmt <statement names>: a comma delimited white list of statements that may be generated');
-        console.log('--without-stmt <statement names>: a comma delimited black list of statements never to generate');
-        console.log('List of accepted statement names: ' + Object.keys(STMT_ARG_TO_ID));
-        console.log('** UglifyJS fuzzer exiting **');
+        println('** UglifyJS fuzzer help **');
+        println('Valid options (optional):');
+        println('<number>: generate this many cases (if used must be first arg)');
+        println('-v: print every generated test case');
+        println('-V: print every 100th generated test case');
+        println('-t <int>: generate this many toplevels per run (more take longer)');
+        println('-r <int>: maximum recursion depth for generator (higher takes longer)');
+        println('-s1 <statement name>: force the first level statement to be this one (see list below)');
+        println('-s2 <statement name>: force the second level statement to be this one (see list below)');
+        println('--no-catch-redef: do not redefine catch variables');
+        println('--no-directive: do not generate directives');
+        println('--use-strict: generate "use strict"');
+        println('--stmt-depth-from-func: reset statement depth counter at each function, counts from global otherwise');
+        println('--only-stmt <statement names>: a comma delimited white list of statements that may be generated');
+        println('--without-stmt <statement names>: a comma delimited black list of statements never to generate');
+        println('List of accepted statement names: ' + Object.keys(STMT_ARG_TO_ID));
+        println('** UglifyJS fuzzer exiting **');
         return 0;
       default:
         // first arg may be a number.
@@ -941,7 +941,17 @@ if (require.main !== module) {
     return;
 }
 
-function try_beautify(code, result) {
+function println(msg) {
+    if (typeof msg != "undefined") process.stdout.write(msg);
+    process.stdout.write("\n");
+}
+
+function errorln(msg) {
+    if (typeof msg != "undefined") process.stderr.write(msg);
+    process.stderr.write("\n");
+}
+
+function try_beautify(code, result, printfn) {
     var beautified = UglifyJS.minify(code, {
         compress: false,
         mangle: false,
@@ -951,15 +961,15 @@ function try_beautify(code, result) {
         },
     });
     if (beautified.error) {
-        console.log("// !!! beautify failed !!!");
-        console.log(beautified.error.stack);
+        printfn("// !!! beautify failed !!!");
+        printfn(beautified.error.stack);
     } else if (sandbox.same_stdout(sandbox.run_code(beautified.code), result)) {
-        console.log("// (beautified)");
-        console.log(beautified.code);
+        printfn("// (beautified)");
+        printfn(beautified.code);
         return;
     }
-    console.log("//");
-    console.log(code);
+    printfn("//");
+    printfn(code);
 }
 
 var default_options = UglifyJS.default_options();
@@ -977,8 +987,8 @@ function log_suspects(minify_options, component) {
             m[component] = o;
             var result = UglifyJS.minify(original_code, m);
             if (result.error) {
-                console.log("Error testing options." + component + "." + name);
-                console.log(result.error);
+                errorln("Error testing options." + component + "." + name);
+                errorln(result.error.stack);
             } else {
                 var r = sandbox.run_code(result.code);
                 return sandbox.same_stdout(original_result, r);
@@ -986,49 +996,49 @@ function log_suspects(minify_options, component) {
         }
     });
     if (suspects.length > 0) {
-        console.log("Suspicious", component, "options:");
+        errorln("Suspicious " + component + " options:");
         suspects.forEach(function(name) {
-            console.log("  " + name);
+            errorln("  " + name);
         });
-        console.log();
+        errorln();
     }
 }
 
 function log(options) {
-    if (!ok) console.log('\n\n\n\n\n\n!!!!!!!!!!\n\n\n');
-    console.log("//=============================================================");
-    if (!ok) console.log("// !!!!!! Failed... round", round);
-    console.log("// original code");
-    try_beautify(original_code, original_result);
-    console.log();
-    console.log();
-    console.log("//-------------------------------------------------------------");
+    if (!ok) errorln('\n\n\n\n\n\n!!!!!!!!!!\n\n\n');
+    errorln("//=============================================================");
+    if (!ok) errorln("// !!!!!! Failed... round " + round);
+    errorln("// original code");
+    try_beautify(original_code, original_result, errorln);
+    errorln();
+    errorln();
+    errorln("//-------------------------------------------------------------");
     if (typeof uglify_code == "string") {
-        console.log("// uglified code");
-        try_beautify(uglify_code, uglify_result);
-        console.log();
-        console.log();
-        console.log("original result:");
-        console.log(original_result);
-        console.log("uglified result:");
-        console.log(uglify_result);
+        errorln("// uglified code");
+        try_beautify(uglify_code, uglify_result, errorln);
+        errorln();
+        errorln();
+        errorln("original result:");
+        errorln(typeof original_result == "string" ? original_result : original_result.stack);
+        errorln("uglified result:");
+        errorln(typeof uglify_result == "string" ? uglify_result : uglify_result.stack);
     } else {
-        console.log("// !!! uglify failed !!!");
-        console.log(uglify_code.stack);
+        errorln("// !!! uglify failed !!!");
+        errorln(uglify_code.stack);
         if (typeof original_result != "string") {
-            console.log();
-            console.log();
-            console.log("original stacktrace:");
-            console.log(original_result.stack);
+            errorln();
+            errorln();
+            errorln("original stacktrace:");
+            errorln(original_result.stack);
         }
     }
-    console.log("minify(options):");
+    errorln("minify(options):");
     options = JSON.parse(options);
-    console.log(options);
-    console.log();
+    errorln(JSON.stringify(options, null, 2));
+    errorln();
     if (!ok && typeof uglify_code == "string") {
         Object.keys(default_options).forEach(log_suspects.bind(null, options));
-        console.log("!!!!!! Failed... round", round);
+        errorln("!!!!!! Failed... round " + round);
     }
 }
 
@@ -1058,19 +1068,19 @@ for (var round = 1; round <= num_iterations; round++) {
         }
         if (verbose || (verbose_interval && !(round % INTERVAL_COUNT)) || !ok) log(options);
         else if (typeof original_result != "string") {
-            console.log("//=============================================================");
-            console.log("// original code");
-            try_beautify(original_code, original_result);
-            console.log();
-            console.log();
-            console.log("original result:");
-            console.log(original_result);
-            console.log();
+            println("//=============================================================");
+            println("// original code");
+            try_beautify(original_code, original_result, println);
+            println();
+            println();
+            println("original result:");
+            println(original_result.stack);
+            println();
         }
         if (!ok && isFinite(num_iterations)) {
-            console.log();
+            println();
             process.exit(1);
         }
     });
 }
-console.log();
+println();