v2.3.1

accomodates the sort behaviour changes made in commit
mishoo/UglifyJS2@aebafad41e.
Signed-off-by: Justin Lau <justin@tclau.com>

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.
@@ -67,7 +80,7 @@ The available options are:
                        cascading statements into sequences.               [string]
     --stats            Display operations run time on STDERR.            [boolean]
     --acorn            Use Acorn for parsing.                            [boolean]
-    --spidermonkey     Assume input fles are SpiderMonkey AST format (as JSON).
+    --spidermonkey     Assume input files are SpiderMonkey AST format (as JSON).
                                                                          [boolean]
     --self             Build itself (UglifyJS2) as a library (implies
                        --wrap=UglifyJS --export-all)                     [boolean]
@@ -78,7 +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 exit.                    [boolean]
 
 Specify `--output` (`-o`) to declare the output file.  Otherwise the output
 goes to STDOUT.
@@ -129,12 +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` (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
@@ -151,15 +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:
@@ -171,26 +190,43 @@ 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
 variables that UglifyJS will assume to be constants (unless defined in
 scope).  For example if you pass `--define DEBUG=false` then, coupled with
 dead code removal UglifyJS will discard the following from the output:
-
-    if (DEBUG) {
-        console.log("debug stuff");
-    }
+```javascript
+if (DEBUG) {
+	console.log("debug stuff");
+}
+```
 
 UglifyJS will warn about the condition being always false and about dropping
 unreachable code; for now there is no option to turn off only this specific
@@ -199,10 +235,11 @@ warning, you can pass `warnings=false` to turn off *all* warnings.
 Another way of doing that is to declare your globals as constants in a
 separate file and include it into the build.  For example you can have a
 `build/defines.js` file with the following:
-
-    const DEBUG = false;
-    const PRODUCTION = true;
-    // etc.
+```javascript
+const DEBUG = false;
+const PRODUCTION = true;
+// etc.
+```
 
 and build your code like this:
 
@@ -213,6 +250,7 @@ will evaluate references to them to the value itself and drop unreachable
 code as usual.  The possible downside of this approach is that the build
 will contain the `const` declarations.
 
+<a name="codegen-options"></a>
 ## Beautifier options
 
 The code generator tries to output shortest code possible by default.  In
@@ -260,14 +298,15 @@ keep only comments that match this regexp.  For example `--comments
 
 Note, however, that there might be situations where comments are lost.  For
 example:
-
-    function f() {
-      /** @preserve Foo Bar */
-      function g() {
-        // this function is never called
-      }
-      return something();
-    }
+```javascript
+function f() {
+	/** @preserve Foo Bar */
+	function g() {
+	  // this function is never called
+	}
+	return something();
+}
+```
 
 Even though it has "@preserve", the comment will be lost because the inner
 function `g` (which is the AST node to which the comment is attached to) is
@@ -309,8 +348,9 @@ API Reference
 
 Assuming installation via NPM, you can load UglifyJS in your application
 like this:
-
-    var UglifyJS = require("uglify-js");
+```javascript
+var UglifyJS = require("uglify-js");
+```
 
 It exports a lot of names, but I'll discuss here the basics that are needed
 for parsing, mangling and compressing a piece of code.  The sequence is (1)
@@ -321,44 +361,49 @@ parse, (2) compress, (3) mangle, (4) generate output code.
 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
+```javascript
+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:
-
-    var result = UglifyJS.minify([ "file1.js", "file2.js", "file3.js" ]);
-    console.log(result.code);
+```javascript
+var result = UglifyJS.minify([ "file1.js", "file2.js", "file3.js" ]);
+console.log(result.code);
+```
 
 To generate a source map:
-
-    var result = UglifyJS.minify([ "file1.js", "file2.js", "file3.js" ], {
-        outSourceMap: "out.js.map"
-    });
-    console.log(result.code); // minified output
-    console.log(result.map);
+```javascript
+var result = UglifyJS.minify([ "file1.js", "file2.js", "file3.js" ], {
+	outSourceMap: "out.js.map"
+});
+console.log(result.code); // minified output
+console.log(result.map);
+```
 
 Note that the source map is not saved in a file, it's just returned in
 `result.map`.  The value passed for `outSourceMap` is only used to set the
 `file` attribute in the source map (see [the spec][sm-spec]).
 
 You can also specify sourceRoot property to be included in source map:
-
-    var result = UglifyJS.minify([ "file1.js", "file2.js", "file3.js" ], {
-        outSourceMap: "out.js.map",
-        sourceRoot: "http://example.com/src"
-    });
-
+```javascript
+var result = UglifyJS.minify([ "file1.js", "file2.js", "file3.js" ], {
+	outSourceMap: "out.js.map",
+	sourceRoot: "http://example.com/src"
+});
+```
 
 If you're compressing compiled JavaScript and have a source map for it, you
 can use the `inSourceMap` argument:
-
-    var result = UglifyJS.minify("compiled.js", {
-        inSourceMap: "compiled.js.map",
-        outSourceMap: "minified.js.map"
-    });
-    // same as before, it returns `code` and `map`
+```javascript
+var result = UglifyJS.minify("compiled.js", {
+	inSourceMap: "compiled.js.map",
+	outSourceMap: "minified.js.map"
+});
+// same as before, it returns `code` and `map`
+```
 
 The `inSourceMap` is only used if you also request `outSourceMap` (it makes
 no sense otherwise).
@@ -366,9 +411,19 @@ no sense otherwise).
 Other options:
 
 - `warnings` (default `false`) — pass `true` to display compressor warnings.
+
 - `fromString` (default `false`) — if you pass `true` then you can pass
   JavaScript source code, rather than file names.
 
+- `mangle` — pass `false` to skip mangling names.
+
+- `output` (default `null`) — pass an object if you wish to specify
+  additional [output options][codegen].  The defaults are optimized
+  for best compression.
+
+- `compress` (default `{}`) — pass `false` to skip compressing entirely.
+  Pass an object to specify custom [compressor options][compressor].
+
 We could add more options to `UglifyJS.minify` — if you need additional
 functionality please suggest!
 
@@ -378,8 +433,9 @@ Following there's more detailed API info, in case the `minify` function is
 too simple for your needs.
 
 #### The parser
-
-    var toplevel_ast = UglifyJS.parse(code, options);
+```javascript
+var toplevel_ast = UglifyJS.parse(code, options);
+```
 
 `options` is optional and if present it must be an object.  The following
 properties are available:
@@ -393,15 +449,16 @@ properties are available:
 The last two options are useful when you'd like to minify multiple files and
 get a single file as the output and a proper source map.  Our CLI tool does
 something like this:
-
-    var toplevel = null;
-    files.forEach(function(file){
-        var code = fs.readFileSync(file);
-        toplevel = UglifyJS.parse(code, {
-            filename: file,
-            toplevel: toplevel
-        });
-    });
+```javascript
+var toplevel = null;
+files.forEach(function(file){
+	var code = fs.readFileSync(file);
+	toplevel = UglifyJS.parse(code, {
+		filename: file,
+		toplevel: toplevel
+	});
+});
+```
 
 After this, we have in `toplevel` a big AST containing all our files, with
 each token having proper information about where it came from.
@@ -415,15 +472,17 @@ referenced, if it is a global or not, if a function is using `eval` or the
 `with` statement etc.  I will discuss this some place else, for now what's
 important to know is that you need to call the following before doing
 anything with the tree:
-
-    toplevel.figure_out_scope()
+```javascript
+toplevel.figure_out_scope()
+```
 
 #### Compression
 
 Like this:
-
-    var compressor = UglifyJS.Compressor(options);
-    var compressed_ast = toplevel.transform(compressor);
+```javascript
+var compressor = UglifyJS.Compressor(options);
+var compressed_ast = toplevel.transform(compressor);
+```
 
 The `options` can be missing.  Available options are discussed above in
 “Compressor options”.  Defaults should lead to best compression in most
@@ -439,23 +498,26 @@ the compressor might drop unused variables / unreachable code and this might
 change the number of identifiers or their position).  Optionally, you can
 call a trick that helps after Gzip (counting character frequency in
 non-mangleable words).  Example:
-
-    compressed_ast.figure_out_scope();
-    compressed_ast.compute_char_frequency();
-    compressed_ast.mangle_names();
+```javascript
+compressed_ast.figure_out_scope();
+compressed_ast.compute_char_frequency();
+compressed_ast.mangle_names();
+```
 
 #### Generating output
 
 AST nodes have a `print` method that takes an output stream.  Essentially,
 to generate code you do this:
-
-    var stream = UglifyJS.OutputStream(options);
-    compressed_ast.print(stream);
-    var code = stream.toString(); // this is your minified code
+```javascript
+var stream = UglifyJS.OutputStream(options);
+compressed_ast.print(stream);
+var code = stream.toString(); // this is your minified code
+```
 
 or, for a shortcut you can do:
-
-    var code = compressed_ast.print_to_string(options);
+```javascript
+var code = compressed_ast.print_to_string(options);
+```
 
 As usual, `options` is optional.  The output stream accepts a lot of otions,
 most of them documented above in section “Beautifier options”.  The two
@@ -493,16 +555,17 @@ to be a `SourceMap` object (which is a thin wrapper on top of the
 [source-map][source-map] library).
 
 Example:
+```javascript
+var source_map = UglifyJS.SourceMap(source_map_options);
+var stream = UglifyJS.OutputStream({
+	...
+	source_map: source_map
+});
+compressed_ast.print(stream);
 
-    var source_map = UglifyJS.SourceMap(source_map_options);
-    var stream = UglifyJS.OutputStream({
-        ...
-        source_map: source_map
-    });
-    compressed_ast.print(stream);
-
-    var code = stream.toString();
-    var map = source_map.toString(); // json output for your source map
+var code = stream.toString();
+var map = source_map.toString(); // json output for your source map
+```
 
 The `source_map_options` (optional) can contain the following properties:
 
@@ -516,3 +579,5 @@ The `source_map_options` (optional) can contain the following properties:
   [acorn]: https://github.com/marijnh/acorn
   [source-map]: https://github.com/mozilla/source-map
   [sm-spec]: https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k/edit
+  [codegen]: http://lisperator.net/uglifyjs/codegen
+  [compressor]: http://lisperator.net/uglifyjs/compress

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\". \
@@ -42,13 +46,14 @@ because of dead code removal or cascading statements into sequences.")
 
     .describe("stats", "Display operations run time on STDERR.")
     .describe("acorn", "Use Acorn for parsing.")
-    .describe("spidermonkey", "Assume input fles are SpiderMonkey AST format (as JSON).")
+    .describe("spidermonkey", "Assume input files are SpiderMonkey AST format (as JSON).")
     .describe("self", "Build itself (UglifyJS2) as a library (implies --wrap=UglifyJS --export-all)")
     .describe("wrap", "Embed everything in a big function, making the “exports” and “global” variables available. \
 You need to pass an argument to this option to specify the name that your module will take when included in, say, a browser.")
     .describe("export-all", "Only used when --wrap, this tells UglifyJS to add code to automatically export all globals.")
     .describe("lint", "Display some scope warnings")
     .describe("v", "Verbose")
+    .describe("V", "Print version number and exit.")
 
     .alias("p", "prefix")
     .alias("o", "output")
@@ -58,15 +63,20 @@ You need to pass an argument to this option to specify the name that your module
     .alias("c", "compress")
     .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")
@@ -74,6 +84,7 @@ You need to pass an argument to this option to specify the name that your module
     .boolean("acorn")
     .boolean("spidermonkey")
     .boolean("lint")
+    .boolean("V")
 
     .wrap(80)
 
@@ -82,6 +93,12 @@ You need to pass an argument to this option to specify the name that your module
 
 normalize(ARGS);
 
+if (ARGS.version || ARGS.V) {
+    var json = require("../package.json");
+    sys.puts(json.name + ' ' + json.version);
+    process.exit(0);
+}
+
 if (ARGS.ast_help) {
     var desc = UglifyJS.describe_ast();
     sys.puts(typeof desc == "string" ? desc : JSON.stringify(desc, null, 2));
@@ -101,12 +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 = {
@@ -195,100 +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 ]----- */
 
@@ -333,17 +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

@@ -285,11 +285,32 @@ 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 = [];
         if (export_all) {
             self.figure_out_scope();
-            var to_export = [];
             self.walk(new TreeWalker(function(node){
                 if (node instanceof AST_SymbolDeclaration && node.definition().global) {
                     if (!find_if(function(n){ return n.name == node.name }, 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){
@@ -883,18 +893,23 @@ merge(Compressor.prototype, {
             && !self.uses_eval
            ) {
             var in_use = [];
+            var initializations = new Dictionary();
             // pass 1: find out which symbols are directly used in
             // this scope (not in nested scopes).
             var scope = this;
             var tw = new TreeWalker(function(node, descend){
                 if (node !== self) {
                     if (node instanceof AST_Defun) {
+                        initializations.add(node.name.name, node);
                         return true; // don't go in nested scopes
                     }
                     if (node instanceof AST_Definitions && scope === self) {
                         node.definitions.forEach(function(def){
-                            if (def.value && def.value.has_side_effects()) {
-                                def.value.walk(tw);
+                            if (def.value) {
+                                initializations.add(def.name.name, def.value);
+                                if (def.value.has_side_effects()) {
+                                    def.value.walk(tw);
+                                }
                             }
                         });
                         return true;
@@ -919,16 +934,15 @@ merge(Compressor.prototype, {
             for (var i = 0; i < in_use.length; ++i) {
                 in_use[i].orig.forEach(function(decl){
                     // undeclared globals will be instanceof AST_SymbolRef
-                    if (decl instanceof AST_SymbolDeclaration) {
-                        decl.init.forEach(function(init){
-                            var tw = new TreeWalker(function(node){
-                                if (node instanceof AST_SymbolRef) {
-                                    push_uniq(in_use, node.definition());
-                                }
-                            });
-                            init.walk(tw);
+                    var init = initializations.get(decl.name);
+                    if (init) init.forEach(function(init){
+                        var tw = new TreeWalker(function(node){
+                            if (node instanceof AST_SymbolRef) {
+                                push_uniq(in_use, node.definition());
+                            }
                         });
-                    }
+                        init.walk(tw);
+                    });
                 });
             }
             // pass 3: we should drop declarations not in_use
@@ -1100,13 +1114,71 @@ merge(Compressor.prototype, {
                 }
             );
             self = self.transform(tt);
-            if (vars_found > 0) hoisted.unshift(make_node(AST_Var, self, {
-                definitions: vars.map(function(def){
-                    def = def.clone();
-                    def.value = null;
-                    return def;
-                })
-            }));
+            if (vars_found > 0) {
+                // collect only vars which don't show up in self's arguments list
+                var defs = [];
+                vars.each(function(def, name){
+                    if (self instanceof AST_Lambda
+                        && find_if(function(x){ return x.name == def.name.name },
+                                   self.argnames)) {
+                        vars.del(name);
+                    } else {
+                        def = def.clone();
+                        def.value = null;
+                        defs.push(def);
+                        vars.set(name, def);
+                    }
+                });
+                if (defs.length > 0) {
+                    // try to merge in assignments
+                    for (var i = 0; i < self.body.length;) {
+                        if (self.body[i] instanceof AST_SimpleStatement) {
+                            var expr = self.body[i].body, sym, assign;
+                            if (expr instanceof AST_Assign
+                                && expr.operator == "="
+                                && (sym = expr.left) instanceof AST_Symbol
+                                && vars.has(sym.name))
+                            {
+                                var def = vars.get(sym.name);
+                                if (def.value) break;
+                                def.value = expr.right;
+                                remove(defs, def);
+                                defs.push(def);
+                                self.body.splice(i, 1);
+                                continue;
+                            }
+                            if (expr instanceof AST_Seq
+                                && (assign = expr.car) instanceof AST_Assign
+                                && assign.operator == "="
+                                && (sym = assign.left) instanceof AST_Symbol
+                                && vars.has(sym.name))
+                            {
+                                var def = vars.get(sym.name);
+                                if (def.value) break;
+                                def.value = assign.right;
+                                remove(defs, def);
+                                defs.push(def);
+                                self.body[i].body = expr.cdr;
+                                continue;
+                            }
+                        }
+                        if (self.body[i] instanceof AST_EmptyStatement) {
+                            self.body.splice(i, 1);
+                            continue;
+                        }
+                        if (self.body[i] instanceof AST_BlockStatement) {
+                            var tmp = [ i, 1 ].concat(self.body[i].body);
+                            self.body.splice.apply(self.body, tmp);
+                            continue;
+                        }
+                        break;
+                    }
+                    defs = make_node(AST_Var, self, {
+                        definitions: defs
+                    });
+                    hoisted.push(defs);
+                };
+            }
             self.body = dirs.concat(hoisted, self.body);
         }
         return self;
@@ -1137,8 +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;
@@ -1356,11 +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 {
@@ -1430,7 +1507,7 @@ merge(Compressor.prototype, {
                     return node;
                 }
             });
-            tt.stack = compressor.stack; // so that's able to see parent nodes
+            tt.stack = compressor.stack.slice(); // so that's able to see parent nodes
             self = self.transform(tt);
         } catch(ex) {
             if (ex !== self) throw ex;
@@ -1504,6 +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: "+",
@@ -1539,7 +1619,7 @@ merge(Compressor.prototype, {
                   case "Function":
                   case "Error":
                   case "Array":
-                    return make_node(AST_Call, self, self);
+                    return make_node(AST_Call, self, self).transform(compressor);
                 }
             }
         }
@@ -1646,8 +1726,8 @@ merge(Compressor.prototype, {
     var commutativeOperators = makePredicate("== === != !== * & | ^");
 
     OPT(AST_Binary, function(self, compressor){
-        function reverse(op) {
-            if (!(self.left.has_side_effects() && self.right.has_side_effects())) {
+        function reverse(op, force) {
+            if (force || !(self.left.has_side_effects() || self.right.has_side_effects())) {
                 if (op) self.operator = op;
                 var tmp = self.left;
                 self.left = self.right;
@@ -1657,7 +1737,10 @@ merge(Compressor.prototype, {
         if (commutativeOperators(self.operator)) {
             if (self.right instanceof AST_Constant
                 && !(self.left instanceof AST_Constant)) {
-                reverse();
+                // if right is a constant, whatever side effects the
+                // left side might have could not influence the
+                // result.  hence, force switch.
+                reverse(null, true);
             }
         }
         self = self.lift_sequences(compressor);
@@ -1674,11 +1757,12 @@ 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;
-                    self.right = make_node(AST_Undefined, self.left).optimize(compressor);
+                    self.right = self.right.expression;
+                    self.left = make_node(AST_Undefined, self.left).optimize(compressor);
                     if (self.operator.length == 2) self.operator += "=";
                 }
             }
@@ -1744,7 +1828,7 @@ merge(Compressor.prototype, {
         }
         if (self.operator == "+" && self.right instanceof AST_String
             && self.right.getValue() === "" && self.left instanceof AST_Binary
-            && self.left.operator == "+" && self.left.is_string()) {
+            && self.left.operator == "+" && self.left.is_string(compressor)) {
             return self.left;
         }
         return self;
@@ -1881,7 +1965,8 @@ merge(Compressor.prototype, {
         var prop = self.property;
         if (prop instanceof AST_String && compressor.option("properties")) {
             prop = prop.getValue();
-            if (is_identifier(prop)) {
+            if (compressor.option("screw_ie8") && RESERVED_WORDS(prop)
+                || !(RESERVED_WORDS(prop)) && is_identifier_string(prop)) {
                 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;
     };
 
@@ -340,23 +345,25 @@ function OutputStream(options) {
     /* -----[ utils ]----- */
 
     function DEFPRINT(nodetype, generator) {
-        nodetype.DEFMETHOD("print", function(stream){
-            var self = this;
-            stream.push_node(self);
-            if (self.needs_parens(stream)) {
-                stream.with_parens(function(){
-                    self.add_comments(stream);
-                    self.add_source_map(stream);
-                    generator(self, stream);
-                });
-            } else {
+        nodetype.DEFMETHOD("_codegen", generator);
+    };
+
+    AST_Node.DEFMETHOD("print", function(stream, force_parens){
+        var self = this, generator = self._codegen;
+        stream.push_node(self);
+        if (force_parens || self.needs_parens(stream)) {
+            stream.with_parens(function(){
                 self.add_comments(stream);
                 self.add_source_map(stream);
                 generator(self, stream);
-            }
-            stream.pop_node();
-        });
-    };
+            });
+        } else {
+            self.add_comments(stream);
+            self.add_source_map(stream);
+            generator(self, stream);
+        }
+        stream.pop_node();
+    });
 
     AST_Node.DEFMETHOD("print_to_string", function(options){
         var s = OutputStream(options);
@@ -373,6 +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);
@@ -467,18 +484,6 @@ function OutputStream(options) {
                 return true;
             }
         }
-        // for (var i = (foo in bar);;); ← perhaps useless, but valid syntax
-        if (this.operator == "in") {
-            // the “NoIn” stuff :-\
-            // UglifyJS 1.3.3 misses this one.
-            if ((p instanceof AST_For || p instanceof AST_ForIn) && p.init === this)
-                return true;
-            if (p instanceof AST_VarDef) {
-                var v = output.parent(1), p2 = output.parent(2);
-                if ((p2 instanceof AST_For || p2 instanceof AST_ForIn) && p2.init === v)
-                    return true;
-            }
-        }
     });
 
     PARENS(AST_PropAccess, function(output){
@@ -509,11 +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
@@ -622,7 +639,11 @@ function OutputStream(options) {
         output.space();
         output.with_parens(function(){
             if (self.init) {
-                self.init.print(output);
+                if (self.init instanceof AST_Definitions) {
+                    self.init.print(output);
+                } else {
+                    parenthesize_for_noin(self.init, output, true);
+                }
                 output.print(";");
                 output.space();
             } else {
@@ -734,7 +755,7 @@ function OutputStream(options) {
         // to the inner IF).  This function checks for this case and
         // adds the block brackets if needed.
         if (!self.body)
-            return output.semicolon();
+            return output.force_semicolon();
         if (self.body instanceof AST_Do
             && output.option("ie_proof")) {
             // https://github.com/mishoo/UglifyJS/issues/#issue/57 IE
@@ -758,7 +779,7 @@ function OutputStream(options) {
             }
             else break;
         }
-        self.body.print(output);
+        force_statement(self.body, output);
     };
     DEFPRINT(AST_If, function(self, output){
         output.print("if");
@@ -866,13 +887,32 @@ function OutputStream(options) {
     DEFPRINT(AST_Const, function(self, output){
         self._do_print(output, "const");
     });
+
+    function parenthesize_for_noin(node, output, noin) {
+        if (!noin) node.print(output);
+        else try {
+            // need to take some precautions here:
+            //    https://github.com/mishoo/UglifyJS2/issues/60
+            node.walk(new TreeWalker(function(node){
+                if (node instanceof AST_Binary && node.operator == "in")
+                    throw output;
+            }));
+            node.print(output);
+        } catch(ex) {
+            if (ex !== output) throw ex;
+            node.print(output, true);
+        }
+    };
+
     DEFPRINT(AST_VarDef, function(self, output){
         self.name.print(output);
         if (self.value) {
             output.space();
             output.print("=");
             output.space();
-            self.value.print(output);
+            var p = output.parent(1);
+            var noin = p instanceof AST_For || p instanceof AST_ForIn;
+            parenthesize_for_noin(self.value, output, noin);
         }
     });
 
@@ -891,7 +931,7 @@ function OutputStream(options) {
     DEFPRINT(AST_New, function(self, output){
         output.print("new");
         output.space();
-        AST_Call.prototype.print.call(self, output);
+        AST_Call.prototype._codegen(self, output);
     });
 
     AST_Seq.DEFMETHOD("_do_print", function(output){
@@ -919,7 +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(".");
             }
@@ -971,8 +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();
         });
@@ -994,7 +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)
@@ -1023,6 +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");
     });
@@ -1046,6 +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) {
@@ -167,6 +167,14 @@ function is_identifier_char(ch) {
     ;
 };
 
+function is_identifier_string(str){
+    for (var i = str.length; --i >= 0;) {
+        if (!is_identifier_char(str.charAt(i)))
+            return false;
+    }
+    return true;
+};
+
 function parse_js_number(num) {
     if (RE_HEX_NUMBER.test(num)) {
         return parseInt(num.substr(2), 16);
@@ -190,12 +198,6 @@ 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);
 };
 
@@ -881,11 +883,14 @@ function parse($TEXT, options) {
     };
 
     var function_ = function(in_statement, ctor) {
-        var name = is("name") ? as_symbol(in_statement
-                                          ? AST_SymbolDefun
-                                          : ctor === AST_Accessor
-                                          ? AST_SymbolAccessor
-                                          : AST_SymbolLambda) : null;
+        var is_accessor = ctor === AST_Accessor;
+        var name = (is("name") ? as_symbol(in_statement
+                                           ? AST_SymbolDefun
+                                           : is_accessor
+                                           ? AST_SymbolAccessor
+                                           : AST_SymbolLambda)
+                    : is_accessor && (is("string") || is("num")) ? as_atom_node()
+                    : null);
         if (in_statement && !name)
             unexpected();
         expect("(");
@@ -1128,7 +1133,7 @@ function parse($TEXT, options) {
             if (first) first = false; else expect(",");
             if (allow_trailing_comma && is("punc", closing)) break;
             if (is("punc", ",") && allow_empty) {
-                a.push(new AST_Undefined({ start: S.token, end: S.token }));
+                a.push(new AST_Hole({ start: S.token, end: S.token }));
             } else {
                 a.push(expression(false));
             }
@@ -1355,7 +1360,7 @@ function parse($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);
+        }
     }
 };
 
@@ -84,9 +88,12 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
         if (node instanceof AST_Scope) {
             node.init_scope_vars(nesting);
             var save_scope = node.parent_scope = scope;
+            var save_labels = labels;
             ++nesting;
             scope = node;
+            labels = new Dictionary();
             descend();
+            labels = save_labels;
             scope = save_scope;
             --nesting;
             return true;        // don't descend again in TreeWalker
@@ -110,9 +117,6 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             labels.del(l.name);
             return true;        // no descend again
         }
-        if (node instanceof AST_SymbolDeclaration) {
-            node.init_scope_vars();
-        }
         if (node instanceof AST_Symbol) {
             node.scope = scope;
         }
@@ -121,15 +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);
-
-            node.init.push(tw.parent());
+            scope.def_function(node);
         }
         else if (node instanceof AST_SymbolDefun) {
             // Careful here, the scope where this should be defined is
@@ -138,14 +134,12 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             // instanceof AST_Scope) but we get to the symbol a bit
             // later.
             (node.scope = scope.parent_scope).def_function(node);
-            node.init.push(tw.parent());
         }
         else if (node instanceof AST_SymbolVar
                  || node instanceof AST_SymbolConst) {
             var def = scope.def_variable(node);
             def.constant = node instanceof AST_SymbolConst;
-            def = tw.parent();
-            if (def.value) node.init.push(def);
+            def.init = tw.parent().value;
         }
         else if (node instanceof AST_SymbolCatch) {
             // XXX: this is wrong according to ECMA-262 (12.4).  the
@@ -246,10 +240,6 @@ AST_SymbolRef.DEFMETHOD("reference", function() {
     this.frame = this.scope.nesting - def.scope.nesting;
 });
 
-AST_SymbolDeclaration.DEFMETHOD("init_scope_vars", function(){
-    this.init = [];
-});
-
 AST_Label.DEFMETHOD("init_scope_vars", function(){
     this.references = [];
 });
@@ -287,14 +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;
@@ -349,8 +339,11 @@ AST_Symbol.DEFMETHOD("global", function(){
 
 AST_Toplevel.DEFMETHOD("_default_mangler_options", function(options){
     return defaults(options, {
-        except : [],
-        eval   : false,
+        except   : [],
+        eval     : false,
+        sort     : false,
+        toplevel : false,
+        screw_ie8 : false
     });
 });
 
@@ -371,12 +364,16 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options){
             return true;        // don't descend again in TreeWalker
         }
         if (node instanceof AST_Scope) {
-            var p = tw.parent();
+            var p = tw.parent(), a = [];
             node.variables.each(function(symbol){
                 if (options.except.indexOf(symbol.name) < 0) {
-                    to_mangle.push(symbol);
+                    a.push(symbol);
                 }
             });
+            if (options.sort) a.sort(function(a, b){
+                return b.references.length - a.references.length;
+            });
+            to_mangle.push.apply(to_mangle, a);
             return;
         }
         if (node instanceof AST_Label) {

lib/utils.js

@@ -255,6 +255,14 @@ Dictionary.prototype = {
         this._values["$" + key] = val;
         return this;
     },
+    add: function(key, val) {
+        if (this.has(key)) {
+            this.get(key).push(val);
+        } else {
+            this.set(key, [ val ]);
+        }
+        return this;
+    },
     get: function(key) { return this._values["$" + key] },
     del: function(key) {
         if (this.has(key)) {

package.json

@@ -3,7 +3,7 @@
     "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
     "homepage": "http://lisperator.net/uglifyjs",
     "main": "tools/node.js",
-    "version": "2.2.0",
+    "version": "2.3.1",
     "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 +1,25 @@
+typeof_eq_undefined: {
+    options = {
+        comparisons: true
+    };
+    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 = void 0 !== b.c }
+}
+
+typeof_eq_undefined_unsafe2: {
+    options = {
+        comparisons: true,
+        unsafe: true
+    };
+    input: { a = "undefined" != typeof b.c }
+    expect: { a = void 0 !== b.c }
+}

test/compress/issue-143.js

@@ -0,0 +1,48 @@
+/**
+ * There was an incorrect sort behaviour documented in issue #143:
+ * (x = f(…)) <= x → x >= (x = f(…))
+ *
+ * For example, let the equation be:
+ * (a = parseInt('100')) <= a
+ *
+ * If a was an integer and has the value of 99,
+ * (a = parseInt('100')) <= a → 100 <= 100 → true
+ *
+ * When transformed incorrectly:
+ * a >= (a = parseInt('100')) → 99 >= 100 → false
+ */
+
+tranformation_sort_order_equal: {
+    options = {
+        comparisons: true,
+    };
+
+    input: { (a = parseInt('100')) == a }
+    expect: { (a = parseInt('100')) == a }
+}
+
+tranformation_sort_order_unequal: {
+    options = {
+        comparisons: true,
+    };
+
+    input: { (a = parseInt('100')) != a }
+    expect: { (a = parseInt('100')) != a }
+}
+
+tranformation_sort_order_lesser_or_equal: {
+    options = {
+        comparisons: true,
+    };
+
+    input: { (a = parseInt('100')) <= a }
+    expect: { (a = parseInt('100')) <= a }
+}
+tranformation_sort_order_greater_or_equal: {
+    options = {
+        comparisons: true,
+    };
+
+    input: { (a = parseInt('100')) >= a }
+    expect: { (a = parseInt('100')) >= a }
+}

test/compress/issue-59.js

@@ -0,0 +1,30 @@
+keep_continue: {
+    options = {
+        dead_code: true,
+        evaluate: true
+    };
+    input: {
+        while (a) {
+            if (b) {
+                switch (true) {
+                  case c():
+                    d();
+                }
+                continue;
+            }
+            f();
+        }
+    }
+    expect: {
+        while (a) {
+            if (b) {
+                switch (true) {
+                  case c():
+                    d();
+                }
+                continue;
+            }
+            f();
+        }
+    }
+}

test/compress/properties.js

@@ -17,9 +17,32 @@ dot_properties: {
     input: {
         a["foo"] = "bar";
         a["if"] = "if";
+        a["*"] = "asterisk";
+        a["\u0EB3"] = "unicode";
     }
     expect: {
         a.foo = "bar";
         a["if"] = "if";
+        a["*"] = "asterisk";
+        a.\u0EB3 = "unicode";
+    }
+}
+
+dot_properties_es5: {
+    options = {
+        properties: true,
+        screw_ie8: true
+    };
+    input: {
+        a["foo"] = "bar";
+        a["if"] = "if";
+        a["*"] = "asterisk";
+        a["\u0EB3"] = "unicode";
+    }
+    expect: {
+        a.foo = "bar";
+        a.if = "if";
+        a["*"] = "asterisk";
+        a.\u0EB3 = "unicode";
     }
 }

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

@@ -56,6 +56,9 @@ exports.minify = function(files, options) {
         inSourceMap  : null,
         fromString   : false,
         warnings     : false,
+        mangle       : {},
+        output       : null,
+        compress     : {}
     });
     if (typeof files == "string")
         files = [ files ];
@@ -73,33 +76,42 @@ exports.minify = function(files, options) {
     });
 
     // 2. compress
-    toplevel.figure_out_scope();
-    var sq = UglifyJS.Compressor({
-        warnings: options.warnings,
-    });
-    toplevel = toplevel.transform(sq);
+    if (options.compress) {
+        var compress = { warnings: options.warnings };
+        UglifyJS.merge(compress, options.compress);
+        toplevel.figure_out_scope();
+        var sq = UglifyJS.Compressor(compress);
+        toplevel = toplevel.transform(sq);
+    }
 
     // 3. mangle
-    toplevel.figure_out_scope();
-    toplevel.compute_char_frequency();
-    toplevel.mangle_names();
+    if (options.mangle) {
+        toplevel.figure_out_scope();
+        toplevel.compute_char_frequency();
+        toplevel.mangle_names(options.mangle);
+    }
 
     // 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 stream = UglifyJS.OutputStream({ 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);
+    }
+    var stream = UglifyJS.OutputStream(output);
     toplevel.print(stream);
     return {
         code : stream + "",
-        map  : map + ""
+        map  : output.source_map + ""
     };
 };