v2.3

See #193

LICENSE

@@ -0,0 +1,29 @@
+UglifyJS is released under the BSD license:
+
+Copyright 2012-2013 (c) Mihai Bazon <mihai.bazon@gmail.com>
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+
+    * Redistributions of source code must retain the above
+      copyright notice, this list of conditions and the following
+      disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials
+      provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER “AS IS” AND ANY
+EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.

README.md

@@ -12,7 +12,14 @@ Chrome and probably Safari).
 Install
 -------
 
-From NPM:
+First make sure you have installed the latest version of [node.js](http://nodejs.org/)
+(You may need to restart your computer after this step).
+
+From NPM for use as a command line app:
+
+    npm install uglify-js -g
+
+From NPM for programmatic use:
 
     npm install uglify-js
 
@@ -42,8 +49,14 @@ The available options are:
                                                                           [string]
     --source-map-root  The path to the original source to be included in the
                        source map.                                        [string]
+    --source-map-url   The path to the source map to be added in //@
+                       sourceMappingURL.  Defaults to the value passed with
+                       --source-map.                                      [string]
     --in-source-map    Input source map, useful if you're compressing JS that was
                        generated from some other original code.
+    --screw-ie8        Pass this flag if you don't care about full compliance with
+                       Internet Explorer 6-8 quirks (by default UglifyJS will try
+                       to be IE-proof).
     -p, --prefix       Skip prefix for original filenames that appear in source
                        maps. For example -p 3 will drop 3 directories from file
                        names and ensure they are relative paths.
@@ -78,8 +91,9 @@ The available options are:
                                                                           [string]
     --export-all       Only used when --wrap, this tells UglifyJS to add code to
                        automatically export all globals.                 [boolean]
+    --lint             Display some scope warnings                       [boolean]
     -v, --verbose      Verbose                                           [boolean]
-    -V, --version      Print version number and exits.                   [boolean]
+    -V, --version      Print version number and exit.                    [boolean]
 
 Specify `--output` (`-o`) to declare the output file.  Otherwise the output
 goes to STDOUT.
@@ -130,12 +144,19 @@ input files from the command line.
 
 ## Mangler options
 
-To enable the mangler you need to pass `--mangle` (`-m`).  Optionally you
-can pass `-m sort=true` (we'll possibly have other flags in the future) in order
-to assign shorter names to most frequently used variables.  This saves a few
-hundred bytes on jQuery before gzip, but the output is _bigger_ after gzip
-(and seems to happen for other libraries I tried it on) therefore it's not
-enabled by default.
+To enable the mangler you need to pass `--mangle` (`-m`).  The following
+(comma-separated) options are supported:
+
+- `sort` — to assign shorter names to most frequently used variables.  This
+  saves a few hundred bytes on jQuery before gzip, but the output is
+  _bigger_ after gzip (and seems to happen for other libraries I tried it
+  on) therefore it's not enabled by default.
+
+- `toplevel` — mangle names declared in the toplevel scope (disabled by
+  default).
+
+- `eval` — mangle names visible in scopes where `eval` or `when` are used
+  (disabled by default).
 
 When mangling is enabled but you want to prevent certain names from being
 mangled, you can declare those names with `--reserved` (`-r`) — pass a
@@ -152,15 +173,12 @@ you can pass a comma-separated list of options.  Options are in the form
 `foo=bar`, or just `foo` (the latter implies a boolean option that you want
 to set `true`; it's effectively a shortcut for `foo=true`).
 
-The defaults should be tuned for maximum compression on most code.  Here are
-the available options (all are `true` by default, except `hoist_vars`):
-
 - `sequences` -- join consecutive simple statements using the comma operator
 - `properties` -- rewrite property access using the dot notation, for
   example `foo["bar"] → foo.bar`
-- `dead-code` -- remove unreachable code
-- `drop-debugger` -- remove `debugger;` statements
-- `unsafe` -- apply "unsafe" transformations (discussion below)
+- `dead_code` -- remove unreachable code
+- `drop_debugger` -- remove `debugger;` statements
+- `unsafe` (default: false) -- apply "unsafe" transformations (discussion below)
 - `conditionals` -- apply optimizations for `if`-s and conditional
   expressions
 - `comparisons` -- apply certain optimizations to binary nodes, for example:
@@ -172,16 +190,32 @@ the available options (all are `true` by default, except `hoist_vars`):
 - `loops` -- optimizations for `do`, `while` and `for` loops when we can
   statically determine the condition
 - `unused` -- drop unreferenced functions and variables
-- `hoist-funs` -- hoist function declarations
-- `hoist-vars` -- hoist `var` declarations (this is `false` by default
-  because it seems to increase the size of the output in general)
-- `if-return` -- optimizations for if/return and if/continue
-- `join-vars` -- join consecutive `var` statements
+- `hoist_funs` -- hoist function declarations
+- `hoist_vars` (default: false) -- hoist `var` declarations (this is `false`
+  by default because it seems to increase the size of the output in general)
+- `if_return` -- optimizations for if/return and if/continue
+- `join_vars` -- join consecutive `var` statements
 - `cascade` -- small optimization for sequences, transform `x, x` into `x`
   and `x = something(), x` into `x = something()`
 - `warnings` -- display warnings when dropping unreachable code or unused
   declarations etc.
 
+### The `unsafe` option
+
+It enables some transformations that *might* break code logic in certain
+contrived cases, but should be fine for most code.  You might want to try it
+on your own code, it should reduce the minified size.  Here's what happens
+when this flag is on:
+
+- `new Array(1, 2, 3)` or `Array(1, 2, 3)` → `[1, 2, 3 ]`
+- `new Object()` → `{}`
+- `String(exp)` or `exp.toString()` → `"" + exp`
+- `new Object/RegExp/Function/Error/Array (...)` → we discard the `new`
+- `typeof foo == "undefined"` → `foo === void 0`
+- `void 0` → `"undefined"` (if there is a variable named "undefined" in
+  scope; we do it because the variable name will be mangled, typically
+  reduced to a single character).
+
 ### Conditional compilation
 
 You can use the `--define` (`-d`) switch in order to declare global
@@ -324,9 +358,10 @@ There's a single toplevel function which combines all the steps.  If you
 don't need additional customization, you might want to go with `minify`.
 Example:
 
-    // see "fromString" below if you need to pass code instead of file name
     var result = UglifyJS.minify("/path/to/file.js");
     console.log(result.code); // minified output
+    // if you need to pass code instead of file name
+    var result = UglifyJS.minify("var b = function () {};", {fromString: true});
 
 You can also compress multiple files:
 

bin/uglifyjs

@@ -7,6 +7,7 @@ var UglifyJS = require("../tools/node");
 var sys = require("util");
 var optimist = require("optimist");
 var fs = require("fs");
+var async = require("async");
 var acorn;
 var ARGS = optimist
     .usage("$0 input1.js [input2.js ...] [options]\n\
@@ -19,7 +20,9 @@ mangling you need to use `-c` and `-m`.\
 ")
     .describe("source-map", "Specify an output file where to generate source map.")
     .describe("source-map-root", "The path to the original source to be included in the source map.")
+    .describe("source-map-url", "The path to the source map to be added in //@ sourceMappingURL.  Defaults to the value passed with --source-map.")
     .describe("in-source-map", "Input source map, useful if you're compressing JS that was generated from some other original code.")
+    .describe("screw-ie8", "Pass this flag if you don't care about full compliance with Internet Explorer 6-8 quirks (by default UglifyJS will try to be IE-proof).")
     .describe("p", "Skip prefix for original filenames that appear in source maps. \
 For example -p 3 will drop 3 directories from file names and ensure they are relative paths.")
     .describe("o", "Output file (default STDOUT).")
@@ -30,6 +33,7 @@ For example -p 3 will drop 3 directories from file names and ensure they are rel
 Pass options like -c hoist_vars=false,if_return=false. \
 Use -c with no argument to use the default compression options.")
     .describe("d", "Global definitions")
+    .describe("e", "Embed everything in a big function, with a configurable parameter/argument list.")
 
     .describe("comments", "Preserve copyright comments in the output. \
 By default this works like Google Closure, keeping JSDoc-style comments that contain \"@license\" or \"@preserve\". \
@@ -60,15 +64,19 @@ You need to pass an argument to this option to specify the name that your module
     .alias("d", "define")
     .alias("r", "reserved")
     .alias("V", "version")
+    .alias("e", "enclose")
 
     .string("source-map")
     .string("source-map-root")
+    .string("source-map-url")
     .string("b")
     .string("m")
     .string("c")
     .string("d")
+    .string("e")
     .string("comments")
     .string("wrap")
+    .boolean("screw-ie8")
     .boolean("export-all")
     .boolean("self")
     .boolean("v")
@@ -110,12 +118,17 @@ var COMPRESS = getOptions("c", true);
 var MANGLE = getOptions("m", true);
 var BEAUTIFY = getOptions("b", true);
 
-if (COMPRESS && ARGS.d) {
-    COMPRESS.global_defs = getOptions("d");
+if (ARGS.d) {
+    if (COMPRESS) COMPRESS.global_defs = getOptions("d");
 }
 
-if (MANGLE && ARGS.r) {
-    MANGLE.except = ARGS.r.replace(/^\s+|\s+$/g).split(/\s*,+\s*/);
+if (ARGS.screw_ie8) {
+    if (COMPRESS) COMPRESS.screw_ie8 = true;
+    if (MANGLE) MANGLE.screw_ie8 = true;
+}
+
+if (ARGS.r) {
+    if (MANGLE) MANGLE.except = ARGS.r.replace(/^\s+|\s+$/g).split(/\s*,+\s*/);
 }
 
 var OUTPUT_OPTIONS = {
@@ -204,100 +217,116 @@ try {
     }
 }
 
-files.forEach(function(file) {
-    var code = read_whole_file(file);
-    if (ARGS.p != null) {
-        file = file.replace(/^\/+/, "").split(/\/+/).slice(ARGS.p).join("/");
+async.eachLimit(files, 1, function (file, cb) {
+    read_whole_file(file, function (err, code) {
+        if (err) {
+            sys.error("ERROR: can't read file: " + filename);
+            process.exit(1);
+        }
+        if (ARGS.p != null) {
+            file = file.replace(/^\/+/, "").split(/\/+/).slice(ARGS.p).join("/");
+        }
+        time_it("parse", function(){
+            if (ARGS.spidermonkey) {
+                var program = JSON.parse(code);
+                if (!TOPLEVEL) TOPLEVEL = program;
+                else TOPLEVEL.body = TOPLEVEL.body.concat(program.body);
+            }
+            else if (ARGS.acorn) {
+                TOPLEVEL = acorn.parse(code, {
+                    locations     : true,
+                    trackComments : true,
+                    sourceFile    : file,
+                    program       : TOPLEVEL
+                });
+            }
+            else {
+                TOPLEVEL = UglifyJS.parse(code, {
+                    filename: file,
+                    toplevel: TOPLEVEL
+                });
+            };
+        });
+        cb();
+    });
+}, function () {
+    if (ARGS.acorn || ARGS.spidermonkey) time_it("convert_ast", function(){
+        TOPLEVEL = UglifyJS.AST_Node.from_mozilla_ast(TOPLEVEL);
+    });
+
+    if (ARGS.wrap) {
+        TOPLEVEL = TOPLEVEL.wrap_commonjs(ARGS.wrap, ARGS.export_all);
     }
-    time_it("parse", function(){
-        if (ARGS.spidermonkey) {
-            var program = JSON.parse(code);
-            if (!TOPLEVEL) TOPLEVEL = program;
-            else TOPLEVEL.body = TOPLEVEL.body.concat(program.body);
+
+    if (ARGS.enclose) {
+        var arg_parameter_list = ARGS.enclose;
+
+        if (!(arg_parameter_list instanceof Array)) {
+            arg_parameter_list = [arg_parameter_list];
         }
-        else if (ARGS.acorn) {
-            TOPLEVEL = acorn.parse(code, {
-                locations     : true,
-                trackComments : true,
-                sourceFile    : file,
-                program       : TOPLEVEL
-            });
-        }
-        else {
-            TOPLEVEL = UglifyJS.parse(code, {
-                filename: file,
-                toplevel: TOPLEVEL
-            });
-        };
+
+        TOPLEVEL = TOPLEVEL.wrap_enclose(arg_parameter_list);
+    }
+
+    var SCOPE_IS_NEEDED = COMPRESS || MANGLE || ARGS.lint;
+
+    if (SCOPE_IS_NEEDED) {
+        time_it("scope", function(){
+            TOPLEVEL.figure_out_scope({ screw_ie8: ARGS.screw_ie8 });
+            if (ARGS.lint) {
+                TOPLEVEL.scope_warnings();
+            }
+        });
+    }
+
+    if (COMPRESS) {
+        time_it("squeeze", function(){
+            TOPLEVEL = TOPLEVEL.transform(compressor);
+        });
+    }
+
+    if (SCOPE_IS_NEEDED) {
+        time_it("scope", function(){
+            TOPLEVEL.figure_out_scope({ screw_ie8: ARGS.screw_ie8 });
+            if (MANGLE) {
+                TOPLEVEL.compute_char_frequency(MANGLE);
+            }
+        });
+    }
+
+    if (MANGLE) time_it("mangle", function(){
+        TOPLEVEL.mangle_names(MANGLE);
     });
-});
-
-if (ARGS.acorn || ARGS.spidermonkey) time_it("convert_ast", function(){
-    TOPLEVEL = UglifyJS.AST_Node.from_mozilla_ast(TOPLEVEL);
-});
-
-if (ARGS.wrap) {
-    TOPLEVEL = TOPLEVEL.wrap_commonjs(ARGS.wrap, ARGS.export_all);
-}
-
-var SCOPE_IS_NEEDED = COMPRESS || MANGLE || ARGS.lint;
-
-if (SCOPE_IS_NEEDED) {
-    time_it("scope", function(){
-        TOPLEVEL.figure_out_scope();
-        if (ARGS.lint) {
-            TOPLEVEL.scope_warnings();
-        }
+    time_it("generate", function(){
+        TOPLEVEL.print(output);
     });
-}
 
-if (COMPRESS) {
-    time_it("squeeze", function(){
-        TOPLEVEL = TOPLEVEL.transform(compressor);
-    });
-}
+    output = output.get();
 
-if (SCOPE_IS_NEEDED) {
-    time_it("scope", function(){
-        TOPLEVEL.figure_out_scope();
-        if (MANGLE) {
-            TOPLEVEL.compute_char_frequency(MANGLE);
-        }
-    });
-}
+    if (SOURCE_MAP) {
+        fs.writeFileSync(ARGS.source_map, SOURCE_MAP, "utf8");
+        output += "\n/*\n//@ sourceMappingURL=" + (ARGS.source_map_url || ARGS.source_map) + "\n*/";
+    }
 
-if (MANGLE) time_it("mangle", function(){
-    TOPLEVEL.mangle_names(MANGLE);
-});
-time_it("generate", function(){
-    TOPLEVEL.print(output);
-});
+    if (OUTPUT_FILE) {
+        fs.writeFileSync(OUTPUT_FILE, output, "utf8");
+    } else {
+        sys.print(output);
+        sys.error("\n");
+    }
 
-output = output.get();
-
-if (SOURCE_MAP) {
-    fs.writeFileSync(ARGS.source_map, SOURCE_MAP, "utf8");
-    output += "\n//@ sourceMappingURL=" + ARGS.source_map;
-}
-
-if (OUTPUT_FILE) {
-    fs.writeFileSync(OUTPUT_FILE, output, "utf8");
-} else {
-    sys.print(output);
-    sys.error("\n");
-}
-
-if (ARGS.stats) {
-    sys.error(UglifyJS.string_template("Timing information (compressed {count} files):", {
-        count: files.length
-    }));
-    for (var i in STATS) if (STATS.hasOwnProperty(i)) {
-        sys.error(UglifyJS.string_template("- {name}: {time}s", {
-            name: i,
-            time: (STATS[i] / 1000).toFixed(3)
+    if (ARGS.stats) {
+        sys.error(UglifyJS.string_template("Timing information (compressed {count} files):", {
+            count: files.length
         }));
+        for (var i in STATS) if (STATS.hasOwnProperty(i)) {
+            sys.error(UglifyJS.string_template("- {name}: {time}s", {
+                name: i,
+                time: (STATS[i] / 1000).toFixed(3)
+            }));
+        }
     }
-}
+});
 
 /* -----[ functions ]----- */
 
@@ -342,17 +371,18 @@ function getOptions(x, constants) {
     return ret;
 }
 
-function read_whole_file(filename) {
+function read_whole_file(filename, cb) {
     if (filename == "-") {
-        // XXX: this sucks.  How does one read the whole STDIN
-        // synchronously?
-        filename = "/dev/stdin";
-    }
-    try {
-        return fs.readFileSync(filename, "utf8");
-    } catch(ex) {
-        sys.error("ERROR: can't read file: " + filename);
-        process.exit(1);
+        var chunks = [];
+        process.stdin.setEncoding('utf-8');
+        process.stdin.on('data', function (chunk) {
+            chunks.push(chunk);
+        }).on('end', function () {
+            cb(null, chunks.join(""));
+        });
+        process.openStdin();
+    } else {
+        fs.readFile(filename, "utf-8", cb);
     }
 }
 

lib/ast.js

@@ -285,6 +285,27 @@ var AST_Toplevel = DEFNODE("Toplevel", "globals", {
     $propdoc: {
         globals: "[Object/S] a map of name -> SymbolDef for all undeclared names",
     },
+    wrap_enclose: function(arg_parameter_pairs) {
+        var self = this;
+        var args = [];
+        var parameters = [];
+
+        arg_parameter_pairs.forEach(function(pair) {
+            var split = pair.split(":");
+
+            args.push(split[0]);
+            parameters.push(split[1]);
+        });
+
+        var wrapped_tl = "(function(" + parameters.join(",") + "){ '$ORIG'; })(" + args.join(",") + ")";
+        wrapped_tl = parse(wrapped_tl);
+        wrapped_tl = wrapped_tl.transform(new TreeTransformer(function before(node){
+            if (node instanceof AST_Directive && node.value == "$ORIG") {
+                return MAP.splice(self.body);
+            }
+        }));
+        return wrapped_tl;
+    },
     wrap_commonjs: function(name, export_all) {
         var self = this;
         var to_export = [];
@@ -863,6 +884,11 @@ var AST_Undefined = DEFNODE("Undefined", null, {
     value: (function(){}())
 }, AST_Atom);
 
+var AST_Hole = DEFNODE("Hole", null, {
+    $documentation: "A hole in an array",
+    value: (function(){}())
+}, AST_Atom);
+
 var AST_Infinity = DEFNODE("Infinity", null, {
     $documentation: "The `Infinity` value",
     value: 1/0

lib/compress.js

@@ -52,7 +52,7 @@ function Compressor(options, false_by_default) {
         properties    : !false_by_default,
         dead_code     : !false_by_default,
         drop_debugger : !false_by_default,
-        unsafe        : !false_by_default,
+        unsafe        : false,
         unsafe_comps  : false,
         conditionals  : !false_by_default,
         comparisons   : !false_by_default,
@@ -66,6 +66,7 @@ function Compressor(options, false_by_default) {
         join_vars     : !false_by_default,
         cascade       : !false_by_default,
         side_effects  : !false_by_default,
+        screw_ie8     : false,
 
         warnings      : true,
         global_defs   : {}
@@ -156,7 +157,7 @@ merge(Compressor.prototype, {
                 value: val
             }).optimize(compressor);
           case "boolean":
-            return make_node(val ? AST_True : AST_False, orig);
+            return make_node(val ? AST_True : AST_False, orig).optimize(compressor);
           case "undefined":
             return make_node(AST_Undefined, orig).optimize(compressor);
           default:
@@ -625,10 +626,24 @@ merge(Compressor.prototype, {
             var e = this.expression;
             switch (this.operator) {
               case "!": return !ev(e);
-              case "typeof": return typeof ev(e);
+              case "typeof":
+                // Function would be evaluated to an array and so typeof would
+                // incorrectly return 'object'. Hence making is a special case.
+                if (e instanceof AST_Function) return typeof function(){};
+
+                e = ev(e);
+
+                // typeof <RegExp> returns "object" or "function" on different platforms
+                // so cannot evaluate reliably
+                if (e instanceof RegExp) throw def;
+
+                return typeof e;
               case "void": return void ev(e);
               case "~": return ~ev(e);
-              case "-": return -ev(e);
+              case "-":
+                e = ev(e);
+                if (e === 0) throw def;
+                return -e;
               case "+": return +ev(e);
             }
             throw def;
@@ -669,12 +684,7 @@ merge(Compressor.prototype, {
         });
         def(AST_SymbolRef, function(){
             var d = this.definition();
-            if (d && d.constant) {
-                var orig = d.orig[0];
-                if (orig) orig = orig.init[0];
-                orig = orig && orig.value;
-                if (orig) return ev(orig);
-            }
+            if (d && d.constant && d.init) return ev(d.init);
             throw def;
         });
     })(function(node, func){
@@ -1199,8 +1209,6 @@ merge(Compressor.prototype, {
                     extract_declarations_from_unreachable_code(compressor, self.body, a);
                     return make_node(AST_BlockStatement, self, { body: a });
                 }
-            } else {
-                return self.body;
             }
         }
         return self;
@@ -1418,11 +1426,18 @@ merge(Compressor.prototype, {
                 body: self.expression
             }).transform(compressor);
         }
-        var last_branch = self.body[self.body.length - 1];
-        if (last_branch) {
-            var stat = last_branch.body[last_branch.body.length - 1]; // last statement
-            if (stat instanceof AST_Break && loop_body(compressor.loopcontrol_target(stat.label)) === self)
-                last_branch.body.pop();
+        for(;;) {
+            var last_branch = self.body[self.body.length - 1];
+            if (last_branch) {
+                var stat = last_branch.body[last_branch.body.length - 1]; // last statement
+                if (stat instanceof AST_Break && loop_body(compressor.loopcontrol_target(stat.label)) === self)
+                    last_branch.body.pop();
+                if (last_branch instanceof AST_Default && last_branch.body.length == 0) {
+                    self.body.pop();
+                    continue;
+                }
+            }
+            break;
         }
         var exp = self.expression.evaluate(compressor);
         out: if (exp.length == 2) try {
@@ -1566,6 +1581,9 @@ merge(Compressor.prototype, {
                     }
                     break;
                   case "String":
+                    if (self.args.length == 0) return make_node(AST_String, self, {
+                        value: ""
+                    });
                     return make_node(AST_Binary, self, {
                         left: self.args[0],
                         operator: "+",
@@ -1709,7 +1727,7 @@ merge(Compressor.prototype, {
 
     OPT(AST_Binary, function(self, compressor){
         function reverse(op) {
-            if (!(self.left.has_side_effects() && self.right.has_side_effects())) {
+            if (!(self.left.has_side_effects() || self.right.has_side_effects())) {
                 if (op) self.operator = op;
                 var tmp = self.left;
                 self.left = self.right;
@@ -1736,7 +1754,8 @@ merge(Compressor.prototype, {
             if (self.left instanceof AST_String
                 && self.left.value == "undefined"
                 && self.right instanceof AST_UnaryPrefix
-                && self.right.operator == "typeof") {
+                && self.right.operator == "typeof"
+                && compressor.option("unsafe")) {
                 if (!(self.right.expression instanceof AST_SymbolRef)
                     || !self.right.expression.undeclared()) {
                     self.left = self.right.expression;
@@ -1943,7 +1962,7 @@ merge(Compressor.prototype, {
         var prop = self.property;
         if (prop instanceof AST_String && compressor.option("properties")) {
             prop = prop.getValue();
-            if (is_identifier(prop)) {
+            if (is_identifier(prop) || compressor.option("screw_ie8")) {
                 return make_node(AST_Dot, self, {
                     expression : self.expression,
                     property   : prop

lib/mozilla-ast.js

@@ -148,12 +148,14 @@
     };
 
     function From_Moz_Unary(M) {
-        return new (M.prefix ? AST_UnaryPrefix : AST_UnaryPostfix)({
+        var prefix = "prefix" in M ? M.prefix
+            : M.type == "UnaryExpression" ? true : false;
+        return new (prefix ? AST_UnaryPrefix : AST_UnaryPostfix)({
             start      : my_start_token(M),
             end        : my_end_token(M),
             operator   : M.operator,
             expression : from_moz(M.argument)
-        })
+        });
     };
 
     var ME_TO_MOZ = {};

lib/output.js

@@ -69,11 +69,16 @@ function OutputStream(options) {
     var current_pos = 0;
     var OUTPUT = "";
 
-    function to_ascii(str) {
+    function to_ascii(str, identifier) {
         return str.replace(/[\u0080-\uffff]/g, function(ch) {
             var code = ch.charCodeAt(0).toString(16);
-            while (code.length < 4) code = "0" + code;
-            return "\\u" + code;
+            if (code.length <= 2 && !identifier) {
+                while (code.length < 2) code = "0" + code;
+                return "\\x" + code;
+            } else {
+                while (code.length < 4) code = "0" + code;
+                return "\\u" + code;
+            }
         });
     };
 
@@ -109,7 +114,7 @@ function OutputStream(options) {
     function make_name(name) {
         name = name.toString();
         if (options.ascii_only)
-            name = to_ascii(name);
+            name = to_ascii(name, true);
         return name;
     };
 
@@ -375,6 +380,16 @@ function OutputStream(options) {
             if (start && !start._comments_dumped) {
                 start._comments_dumped = true;
                 var comments = start.comments_before;
+
+                // XXX: ugly fix for https://github.com/mishoo/UglifyJS2/issues/112
+                //      if this node is `return` or `throw`, we cannot allow comments before
+                //      the returned or thrown value.
+                if (self instanceof AST_Exit &&
+                    self.value && self.value.start.comments_before.length > 0) {
+                    comments = (comments || []).concat(self.value.start.comments_before);
+                    self.value.start.comments_before = [];
+                }
+
                 if (c.test) {
                     comments = comments.filter(function(comment){
                         return c.test(comment.value);
@@ -499,11 +514,23 @@ function OutputStream(options) {
     PARENS(AST_New, function(output){
         var p = output.parent();
         if (no_constructor_parens(this, output)
-            && (p instanceof AST_Dot // (new Date).getTime()
+            && (p instanceof AST_PropAccess // (new Date).getTime(), (new Date)["getTime"]()
                 || p instanceof AST_Call && p.expression === this)) // (new foo)(bar)
             return true;
     });
 
+    PARENS(AST_Number, function(output){
+        var p = output.parent();
+        if (this.getValue() < 0 && p instanceof AST_PropAccess && p.expression === this)
+            return true;
+    });
+
+    PARENS(AST_NaN, function(output){
+        var p = output.parent();
+        if (p instanceof AST_PropAccess && p.expression === this)
+            return true;
+    });
+
     function assign_and_conditional_paren_rules(output) {
         var p = output.parent();
         // !(a = false) → true
@@ -932,7 +959,7 @@ function OutputStream(options) {
     DEFPRINT(AST_Dot, function(self, output){
         var expr = self.expression;
         expr.print(output);
-        if (expr instanceof AST_Number) {
+        if (expr instanceof AST_Number && expr.getValue() >= 0) {
             if (!/[xa-f.]/i.test(output.last())) {
                 output.print(".");
             }
@@ -984,8 +1011,7 @@ function OutputStream(options) {
             if (len > 0) output.space();
             a.forEach(function(exp, i){
                 if (i) output.comma();
-                if (!(exp instanceof AST_Undefined))
-                    exp.print(output);
+                exp.print(output);
             });
             if (len > 0) output.space();
         });
@@ -1007,7 +1033,7 @@ function OutputStream(options) {
     DEFPRINT(AST_ObjectKeyVal, function(self, output){
         var key = self.key;
         if (output.option("quote_keys")) {
-            output.print_string(key);
+            output.print_string(key + "");
         } else if ((typeof key == "number"
                     || !output.option("beautify")
                     && +key + "" == key)
@@ -1036,6 +1062,7 @@ function OutputStream(options) {
     DEFPRINT(AST_Undefined, function(self, output){
         output.print("void 0");
     });
+    DEFPRINT(AST_Hole, noop);
     DEFPRINT(AST_Infinity, function(self, output){
         output.print("1/0");
     });
@@ -1059,6 +1086,9 @@ function OutputStream(options) {
         if (output.option("ascii_only"))
             str = output.to_ascii(str);
         output.print(str);
+        var p = output.parent();
+        if (p instanceof AST_Binary && /^in/.test(p.operator) && p.left === self)
+            output.print(" ");
     });
 
     function force_statement(stat, output) {

lib/parse.js

@@ -149,7 +149,7 @@ function is_unicode_connector_punctuation(ch) {
 };
 
 function is_identifier(name) {
-    return /^[a-z_$][a-z0-9_$]*$/i.test(name) && !RESERVED_WORDS(name);
+    return !RESERVED_WORDS(name) && /^[a-z_$][a-z0-9_$]*$/i.test(name);
 };
 
 function is_identifier_start(code) {
@@ -190,12 +190,6 @@ JS_Parse_Error.prototype.toString = function() {
 };
 
 function js_error(message, filename, line, col, pos) {
-    AST_Node.warn("ERROR: {message} [{file}:{line},{col}]", {
-        message: message,
-        file: filename,
-        line: line,
-        col: col
-    });
     throw new JS_Parse_Error(message, line, col, pos);
 };
 
@@ -1131,7 +1125,7 @@ function parse($TEXT, options) {
             if (first) first = false; else expect(",");
             if (allow_trailing_comma && is("punc", closing)) break;
             if (is("punc", ",") && allow_empty) {
-                a.push(new AST_Undefined({ start: S.token, end: S.token }));
+                a.push(new AST_Hole({ start: S.token, end: S.token }));
             } else {
                 a.push(expression(false));
             }
@@ -1358,7 +1352,7 @@ function parse($TEXT, options) {
                     left     : left,
                     operator : val,
                     right    : maybe_assign(no_in),
-                    end      : peek()
+                    end      : prev()
                 });
             }
             croak("Invalid assignment");

lib/scope.js

@@ -57,13 +57,17 @@ function SymbolDef(scope, index, orig) {
 
 SymbolDef.prototype = {
     unmangleable: function(options) {
-        return this.global
+        return (this.global && !(options && options.toplevel))
             || this.undeclared
             || (!(options && options.eval) && (this.scope.uses_eval || this.scope.uses_with));
     },
     mangle: function(options) {
-        if (!this.mangled_name && !this.unmangleable(options))
-            this.mangled_name = this.scope.next_mangled(options);
+        if (!this.mangled_name && !this.unmangleable(options)) {
+            var s = this.scope;
+            if (this.orig[0] instanceof AST_SymbolLambda && !options.screw_ie8)
+                s = s.parent_scope;
+            this.mangled_name = s.next_mangled(options);
+        }
     }
 };
 
@@ -121,13 +125,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             node.init_scope_vars();
         }
         if (node instanceof AST_SymbolLambda) {
-            //scope.def_function(node);
-            //
-            // https://github.com/mishoo/UglifyJS2/issues/24 — MSIE
-            // leaks function expression names into the containing
-            // scope.  Don't like this fix but seems we can't do any
-            // better.  IE: please die. Please!
-            (node.scope = scope.parent_scope).def_function(node);
+            scope.def_function(node);
         }
         else if (node instanceof AST_SymbolDefun) {
             // Careful here, the scope where this should be defined is
@@ -141,7 +139,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
                  || node instanceof AST_SymbolConst) {
             var def = scope.def_variable(node);
             def.constant = node instanceof AST_SymbolConst;
-            def = tw.parent();
+            def.init = tw.parent().value;
         }
         else if (node instanceof AST_SymbolCatch) {
             // XXX: this is wrong according to ECMA-262 (12.4).  the
@@ -279,14 +277,14 @@ AST_Scope.DEFMETHOD("def_variable", function(symbol){
 });
 
 AST_Scope.DEFMETHOD("next_mangled", function(options){
-    var ext = this.enclosed, n = ext.length;
+    var ext = this.enclosed;
     out: while (true) {
         var m = base54(++this.cname);
         if (!is_identifier(m)) continue; // skip over "do"
         // we must ensure that the mangled name does not shadow a name
         // from some parent scope that is referenced in this or in
         // inner scopes.
-        for (var i = n; --i >= 0;) {
+        for (var i = ext.length; --i >= 0;) {
             var sym = ext[i];
             var name = sym.mangled_name || (sym.unmangleable(options) && sym.name);
             if (m == name) continue out;
@@ -341,9 +339,11 @@ AST_Symbol.DEFMETHOD("global", function(){
 
 AST_Toplevel.DEFMETHOD("_default_mangler_options", function(options){
     return defaults(options, {
-        except : [],
-        eval   : false,
-        sort   : false
+        except   : [],
+        eval     : false,
+        sort     : false,
+        toplevel : false,
+        screw_ie8 : false
     });
 });
 

package.json

@@ -3,7 +3,7 @@
     "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
     "homepage": "http://lisperator.net/uglifyjs",
     "main": "tools/node.js",
-    "version": "2.2.3",
+    "version": "2.3",
     "engines": { "node" : ">=0.4.0" },
     "maintainers": [{
         "name": "Mihai Bazon",
@@ -15,6 +15,7 @@
         "url": "https://github.com/mishoo/UglifyJS2.git"
     }],
     "dependencies": {
+        "async"      : "~0.2.6",
         "source-map" : "~0.1.7",
         "optimist"   : "~0.3.5"
     },

test/compress/arrays.js

@@ -0,0 +1,12 @@
+holes_and_undefined: {
+    input: {
+        x = [1, 2, undefined];
+        y = [1, , 2, ];
+        z = [1, undefined, 3];
+    }
+    expect: {
+        x=[1,2,void 0];
+        y=[1,,2];
+        z=[1,void 0,3];
+    }
+}

test/compress/issue-105.js

@@ -0,0 +1,17 @@
+typeof_eq_undefined: {
+    options = {
+        comparisons: true,
+        unsafe: false
+    };
+    input: { a = typeof b.c != "undefined" }
+    expect: { a = "undefined" != typeof b.c }
+}
+
+typeof_eq_undefined_unsafe: {
+    options = {
+        comparisons: true,
+        unsafe: true
+    };
+    input: { a = typeof b.c != "undefined" }
+    expect: { a = b.c !== void 0 }
+}

test/compress/properties.js

@@ -23,3 +23,18 @@ dot_properties: {
         a["if"] = "if";
     }
 }
+
+dot_properties_es5: {
+    options = {
+        properties: true,
+        screw_ie8: true
+    };
+    input: {
+        a["foo"] = "bar";
+        a["if"] = "if";
+    }
+    expect: {
+        a.foo = "bar";
+        a.if = "if";
+    }
+}

test/compress/switch.js

@@ -208,3 +208,53 @@ constant_switch_9: {
         }
     }
 }
+
+drop_default_1: {
+    options = { dead_code: true };
+    input: {
+        switch (foo) {
+          case 'bar': baz();
+          default:
+        }
+    }
+    expect: {
+        switch (foo) {
+          case 'bar': baz();
+        }
+    }
+}
+
+drop_default_2: {
+    options = { dead_code: true };
+    input: {
+        switch (foo) {
+          case 'bar': baz(); break;
+          default:
+            break;
+        }
+    }
+    expect: {
+        switch (foo) {
+          case 'bar': baz();
+        }
+    }
+}
+
+keep_default: {
+    options = { dead_code: true };
+    input: {
+        switch (foo) {
+          case 'bar': baz();
+          default:
+            something();
+            break;
+        }
+    }
+    expect: {
+        switch (foo) {
+          case 'bar': baz();
+          default:
+            something();
+        }
+    }
+}

test/compress/typeof.js

@@ -0,0 +1,25 @@
+typeof_evaluation: {
+    options = {
+        evaluate: true
+    };
+    input: {
+        a = typeof 1;
+        b = typeof 'test';
+        c = typeof [];
+        d = typeof {};
+        e = typeof /./;
+        f = typeof false;
+        g = typeof function(){};
+        h = typeof undefined;
+    }
+    expect: {
+        a='number';
+        b='string';
+        c=typeof[];
+        d=typeof{};
+        e=typeof/./;
+        f='boolean';
+        g='function';
+        h='undefined';
+    }
+}

tools/node.js

@@ -92,17 +92,18 @@ exports.minify = function(files, options) {
     }
 
     // 4. output
-    var map = null;
-    var inMap = null;
-    if (options.inSourceMap) {
+    var inMap = options.inSourceMap;
+    var output = {};
+    if (typeof options.inSourceMap == "string") {
         inMap = fs.readFileSync(options.inSourceMap, "utf8");
     }
-    if (options.outSourceMap) map = UglifyJS.SourceMap({
-        file: options.outSourceMap,
-        orig: inMap,
-        root: options.sourceRoot
-    });
-    var output = { source_map: map };
+    if (options.outSourceMap) {
+        output.source_map = UglifyJS.SourceMap({
+            file: options.outSourceMap,
+            orig: inMap,
+            root: options.sourceRoot
+        });
+    }
     if (options.output) {
         UglifyJS.merge(output, options.output);
     }
@@ -110,7 +111,7 @@ exports.minify = function(files, options) {
     toplevel.print(stream);
     return {
         code : stream + "",
-        map  : map + ""
+        map  : output.source_map + ""
     };
 };