Better fix for #343

We can in fact lift sequences, but only if the operation is assignment and
the left-hand side has no side effects nor property access -- that should
guarantee that whatever we place before it cannot affect the sense of the
assignment.

Dropped contrived test case (too hard to support it now), added a more
meaningful one.

.gitignore

@@ -1 +1,2 @@
 tmp/
+node_modules/

.travis.yml

@@ -0,0 +1,7 @@
+language: node_js
+node_js:
+    - "0.4"
+    - "0.6"
+    - "0.8"
+    - "0.10"
+    - "0.11"

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

@@ -1,5 +1,6 @@
 UglifyJS 2
 ==========
+[![Build Status](https://travis-ci.org/mishoo/UglifyJS2.png)](https://travis-ci.org/mishoo/UglifyJS2)
 
 UglifyJS is a JavaScript parser, minifier, compressor or beautifier toolkit.
 
@@ -12,9 +13,16 @@ 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).
 
-    npm install uglify-js2
+From NPM for use as a command line app:
+
+    npm install uglify-js -g
+
+From NPM for programmatic use:
+
+    npm install uglify-js
 
 From Git:
 
@@ -25,7 +33,7 @@ From Git:
 Usage
 -----
 
-    uglifyjs2 [input files] [options]
+    uglifyjs [input files] [options]
 
 UglifyJS2 can take multiple input files.  It's recommended that you pass the
 input files first, then pass the options.  UglifyJS will parse input files
@@ -38,47 +46,68 @@ files.
 
 The available options are:
 
-    --source-map       Specify an output file where to generate source map.
-                                                                          [string]
-    --source-map-root  The path to the original source to be included in the
-                       source map.                                        [string]
-    --in-source-map    Input source map, useful if you're compressing JS that was
-                       generated from some other original code.
-    -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.
-    -o, --output       Output file (default STDOUT).
-    -b, --beautify     Beautify output/specify output options.            [string]
-    -m, --mangle       Mangle names/pass mangler options.                 [string]
-    -r, --reserved     Reserved names to exclude from mangling.
-    -c, --compress     Enable compressor/pass compressor options. Pass options
-                       like -c hoist_vars=false,if_return=false. Use -c with no
-                       argument to use the default compression options.   [string]
-    -d, --define       Global definitions                                 [string]
-    --comments         Preserve copyright comments in the output. By default this
-                       works like Google Closure, keeping JSDoc-style comments
-                       that contain "@license" or "@preserve". You can optionally
-                       pass one of the following arguments to this flag:
-                       - "all" to keep all comments
-                       - a valid JS regexp (needs to start with a slash) to keep
-                       only comments that match.
-                       Note that currently not *all* comments can be kept when
-                       compression is on, because of dead code removal or
-                       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).
-                                                                         [boolean]
-    --self             Build itself (UglifyJS2) as a library (implies
-                       --wrap=UglifyJS --export-all)                     [boolean]
-    --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.
-                                                                          [string]
-    --export-all       Only used when --wrap, this tells UglifyJS to add code to
-                       automatically export all globals.                 [boolean]
-    -v, --verbose      Verbose                                           [boolean]
+```
+  --source-map       Specify an output file where to generate source map.
+                                                                        [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).                         [boolean]
+  --expr             Parse a single expression, rather than a program (for
+                     parsing JSON)                                     [boolean]
+  -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. You can also
+                     specify -p relative, which will make UglifyJS figure out
+                     itself the relative paths between original sources, the
+                     source map and the output file.                    [string]
+  -o, --output       Output file (default STDOUT).
+  -b, --beautify     Beautify output/specify output options.            [string]
+  -m, --mangle       Mangle names/pass mangler options.                 [string]
+  -r, --reserved     Reserved names to exclude from mangling.
+  -c, --compress     Enable compressor/pass compressor options. Pass options
+                     like -c hoist_vars=false,if_return=false. Use -c with no
+                     argument to use the default compression options.   [string]
+  -d, --define       Global definitions                                 [string]
+  -e, --enclose      Embed everything in a big function, with a configurable
+                     parameter/argument list.                           [string]
+  --comments         Preserve copyright comments in the output. By default this
+                     works like Google Closure, keeping JSDoc-style comments
+                     that contain "@license" or "@preserve". You can optionally
+                     pass one of the following arguments to this flag:
+                     - "all" to keep all comments
+                     - a valid JS regexp (needs to start with a slash) to keep
+                     only comments that match.
+                     Note that currently not *all* comments can be kept when
+                     compression is on, because of dead code removal or
+                     cascading statements into sequences.               [string]
+  --preamble         Preamble to prepend to the output.  You can use this to
+                     insert a comment, for example for licensing information.
+                     This will not be parsed, but the source map will adjust
+                     for its presence.
+  --stats            Display operations run time on STDERR.            [boolean]
+  --acorn            Use Acorn for parsing.                            [boolean]
+  --spidermonkey     Assume input files are SpiderMonkey AST format (as JSON).
+                                                                       [boolean]
+  --self             Build itself (UglifyJS2) as a library (implies
+                     --wrap=UglifyJS --export-all)                     [boolean]
+  --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.
+                                                                        [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.
@@ -98,12 +127,12 @@ map.
 
 For example:
 
-    uglifyjs2 /home/doe/work/foo/src/js/file1.js \
-              /home/doe/work/foo/src/js/file2.js \
-              -o foo.min.js \
-              --source-map foo.min.js.map \
-              --source-map-root http://foo.com/src \
-              -p 5 -c -m
+    uglifyjs /home/doe/work/foo/src/js/file1.js \
+             /home/doe/work/foo/src/js/file2.js \
+             -o foo.min.js \
+             --source-map foo.min.js.map \
+             --source-map-root http://foo.com/src \
+             -p 5 -c -m
 
 The above will compress and mangle `file1.js` and `file2.js`, will drop the
 output in `foo.min.js` and the source map in `foo.min.js.map`.  The source
@@ -129,18 +158,25 @@ 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
 comma-separated list of names.  For example:
 
-    uglifyjs2 ... -m -r '$,require,exports'
+    uglifyjs ... -m -r '$,require,exports'
 
 to prevent the `require`, `exports` and `$` names from being changed.
 
@@ -151,46 +187,95 @@ 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:
   `!(a <= b) → a > b` (only when `unsafe`), attempts to negate binary nodes,
   e.g. `a = !b && !c && !d && !e → a=!(b||c||d||e)` etc.
+
 - `evaluate` -- attempt to evaluate constant expressions
+
 - `booleans` -- various optimizations for boolean context, for example `!!a
   ? b : c → a ? b : c`
+
 - `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.
 
+- `negate_iife` -- negate "Immediately-Called Function Expressions"
+  where the return value is discarded, to avoid the parens that the
+  code generator would insert.
+
+- `pure_getters` -- the default is `false`.  If you pass `true` for
+  this, UglifyJS will assume that object property access
+  (e.g. `foo.bar` or `foo["bar"]`) doesn't have any side effects.
+
+- `pure_funcs` -- default `null`.  You can pass an array of names and
+  UglifyJS will assume that those functions do not produce side
+  effects.  DANGER: will not check if the name is redefined in scope.
+  An example case here, for instance `var q = Math.floor(a/b)`.  If
+  variable `q` is not used elsewhere, UglifyJS will drop it, but will
+  still keep the `Math.floor(a/b)`, not knowing what it does.  You can
+  pass `pure_funcs: [ 'Math.floor' ]` to let it know that this
+  function won't produce any side effect, in which case the whole
+  statement would get discarded.  The current implementation adds some
+  overhead (compression will be slower).
+
+### 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
@@ -199,20 +284,22 @@ 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:
 
-    uglifyjs2 build/defines.js js/foo.js js/bar.js... -c
+    uglifyjs build/defines.js js/foo.js js/bar.js... -c
 
 UglifyJS will notice the constants and, since they cannot be altered, it
 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
@@ -238,9 +325,6 @@ can pass additional arguments that control the code output:
   It doesn't work very well currently, but it does make the code generated
   by UglifyJS more readable.
 - `max-line-len` (default 32000) -- maximum line length (for uglified code)
-- `ie-proof` (default `true`) -- generate “IE-proof” code (for now this
-  means add brackets around the do/while in code like this: `if (foo) do
-  something(); while (bar); else ...`.
 - `bracketize` (default `false`) -- always insert brackets in `if`, `for`,
   `do`, `while` or `with` statements, even if their body is a single
   statement.
@@ -248,6 +332,10 @@ can pass additional arguments that control the code output:
   you pass `false` then whenever possible we will use a newline instead of a
   semicolon, leading to more readable output of uglified code (size before
   gzip could be smaller; size after gzip insignificantly larger).
+- `preamble` (default `null`) -- when passed it must be a string and
+  it will be prepended to the output literally.  The source map will
+  adjust for this text.  Can be used to insert a comment containing
+  licensing information, for example.
 
 ### Keeping copyright notices or other comments
 
@@ -260,14 +348,15 @@ 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
@@ -288,7 +377,7 @@ SpiderMonkey AST.  It has a small CLI utility that parses one file and dumps
 the AST in JSON on the standard output.  To use UglifyJS to mangle and
 compress that:
 
-    acorn file.js | uglifyjs2 --spidermonkey -m -c
+    acorn file.js | uglifyjs --spidermonkey -m -c
 
 The `--spidermonkey` option tells UglifyJS that all input files are not
 JavaScript, but JS code described in SpiderMonkey AST in JSON.  Therefore we
@@ -309,8 +398,9 @@ API Reference
 
 Assuming installation via NPM, you can load UglifyJS in your application
 like this:
-
-    var UglifyJS = require("uglify-js2");
+```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 +411,49 @@ 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 +461,19 @@ 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 +483,9 @@ 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 +499,16 @@ 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 +522,17 @@ 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 +548,26 @@ 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 +605,17 @@ 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 +629,5 @@ 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 +7,8 @@ var UglifyJS = require("../tools/node");
 var sys = require("util");
 var optimist = require("optimist");
 var fs = require("fs");
+var path = require("path");
+var async = require("async");
 var acorn;
 var ARGS = optimist
     .usage("$0 input1.js [input2.js ...] [options]\n\
@@ -19,9 +21,14 @@ 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("expr", "Parse a single expression, rather than a program (for parsing JSON)")
     .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.")
+For example -p 3 will drop 3 directories from file names and ensure they are relative paths. \
+You can also specify -p relative, which will make UglifyJS figure out itself the relative paths between original sources, \
+the source map and the output file.")
     .describe("o", "Output file (default STDOUT).")
     .describe("b", "Beautify output/specify output options.")
     .describe("m", "Mangle names/pass mangler options.")
@@ -30,6 +37,7 @@ 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\". \
@@ -40,15 +48,20 @@ You can optionally pass one of the following arguments to this flag:\n\
 Note that currently not *all* comments can be kept when compression is on, \
 because of dead code removal or cascading statements into sequences.")
 
+    .describe("preamble", "Preamble to prepend to the output.  You can use this to insert a \
+comment, for example for licensing information.  This will not be \
+parsed, but the source map will adjust for its presence.")
+
     .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 +71,23 @@ 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")
+    .string("p")
+
+    .boolean("expr")
+    .boolean("screw-ie8")
     .boolean("export-all")
     .boolean("self")
     .boolean("v")
@@ -74,6 +95,7 @@ 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 +104,12 @@ 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));
@@ -101,18 +129,25 @@ 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+$/g).split(/\s*,+\s*/);
+if (ARGS.r) {
+    if (MANGLE) MANGLE.except = ARGS.r.replace(/^\s+|\s+$/g).split(/\s*,+\s*/);
 }
 
 var OUTPUT_OPTIONS = {
-    beautify: BEAUTIFY ? true : false
+    beautify: BEAUTIFY ? true : false,
+    preamble: ARGS.preamble || null,
 };
 
+if (ARGS.screw_ie8) {
+    if (COMPRESS) COMPRESS.screw_ie8 = true;
+    if (MANGLE) MANGLE.screw_ie8 = true;
+    OUTPUT_OPTIONS.screw_ie8 = true;
+}
+
 if (BEAUTIFY)
     UglifyJS.merge(OUTPUT_OPTIONS, BEAUTIFY);
 
@@ -174,9 +209,10 @@ if (files.filter(function(el){ return el == "-" }).length > 1) {
 var STATS = {};
 var OUTPUT_FILE = ARGS.o;
 var TOPLEVEL = null;
+var P_RELATIVE = ARGS.p && ARGS.p == "relative";
 
 var SOURCE_MAP = ARGS.source_map ? UglifyJS.SourceMap({
-    file: OUTPUT_FILE,
+    file: P_RELATIVE ? path.relative(path.dirname(ARGS.source_map), OUTPUT_FILE) : OUTPUT_FILE,
     root: ARGS.source_map_root,
     orig: ORIG_MAP,
 }) : null;
@@ -195,100 +231,139 @@ 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: " + file);
+            process.exit(1);
+        }
+        if (ARGS.p != null) {
+            if (P_RELATIVE) {
+                file = path.relative(path.dirname(ARGS.source_map), file);
+            } else {
+                var p = parseInt(ARGS.p, 10);
+                if (!isNaN(p)) {
+                    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,
+                    sourceFile    : file,
+                    program       : TOPLEVEL
+                });
+            }
+            else {
+                try {
+                    TOPLEVEL = UglifyJS.parse(code, {
+                        filename   : file,
+                        toplevel   : TOPLEVEL,
+                        expression : ARGS.expr,
+                    });
+                } catch(ex) {
+                    if (ex instanceof UglifyJS.JS_Parse_Error) {
+                        sys.error("Parse error at " + file + ":" + ex.line + "," + ex.col);
+                        sys.error(ex.message);
+                        sys.error(ex.stack);
+                        process.exit(1);
+                    }
+                    throw ex;
+                }
+            };
+        });
+        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 === true) {
+            arg_parameter_list = [];
         }
-        else if (ARGS.acorn) {
-            TOPLEVEL = acorn.parse(code, {
-                locations     : true,
-                trackComments : true,
-                sourceFile    : file,
-                program       : TOPLEVEL
-            });
+        else if (!(arg_parameter_list instanceof Array)) {
+            arg_parameter_list = [arg_parameter_list];
         }
-        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();
-        }
-    });
-}
+    if (SOURCE_MAP) {
+        fs.writeFileSync(ARGS.source_map, SOURCE_MAP, "utf8");
+        var source_map_url = ARGS.source_map_url || (
+            P_RELATIVE
+                ? path.relative(path.dirname(OUTPUT_FILE), ARGS.source_map)
+                : ARGS.source_map
+        );
+        output += "\n//# sourceMappingURL=" + source_map_url;
+    }
 
-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 ]----- */
 
@@ -306,7 +381,7 @@ function getOptions(x, constants) {
     if (x !== true) {
         var ast;
         try {
-            ast = UglifyJS.parse(x);
+            ast = UglifyJS.parse(x, { expression: true });
         } catch(ex) {
             if (ex instanceof UglifyJS.JS_Parse_Error) {
                 sys.error("Error parsing arguments in: " + x);
@@ -314,8 +389,6 @@ function getOptions(x, constants) {
             }
         }
         ast.walk(new UglifyJS.TreeWalker(function(node){
-            if (node instanceof UglifyJS.AST_Toplevel) return; // descend
-            if (node instanceof UglifyJS.AST_SimpleStatement) return; // descend
             if (node instanceof UglifyJS.AST_Seq) return; // descend
             if (node instanceof UglifyJS.AST_Assign) {
                 var name = node.left.print_to_string({ beautify: false }).replace(/-/g, "_");
@@ -325,6 +398,11 @@ function getOptions(x, constants) {
                 ret[name] = value;
                 return true;    // no descend
             }
+            if (node instanceof UglifyJS.AST_Symbol || node instanceof UglifyJS.AST_Binary) {
+                var name = node.print_to_string({ beautify: false }).replace(/-/g, "_");
+                ret[name] = true;
+                return true;    // no descend
+            }
             sys.error(node.TYPE)
             sys.error("Error parsing arguments in: " + x);
             process.exit(1);
@@ -333,17 +411,18 @@ 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

@@ -197,6 +197,10 @@ var AST_LabeledStatement = DEFNODE("LabeledStatement", "label", {
     }
 }, AST_StatementWithBody);
 
+var AST_IterationStatement = DEFNODE("IterationStatement", null, {
+    $documentation: "Internal class.  All loops inherit from it."
+}, AST_StatementWithBody);
+
 var AST_DWLoop = DEFNODE("DWLoop", "condition", {
     $documentation: "Base class for do/while statements",
     $propdoc: {
@@ -208,7 +212,7 @@ var AST_DWLoop = DEFNODE("DWLoop", "condition", {
             this.body._walk(visitor);
         });
     }
-}, AST_StatementWithBody);
+}, AST_IterationStatement);
 
 var AST_Do = DEFNODE("Do", null, {
     $documentation: "A `do` statement",
@@ -233,7 +237,7 @@ var AST_For = DEFNODE("For", "init condition step", {
             this.body._walk(visitor);
         });
     }
-}, AST_StatementWithBody);
+}, AST_IterationStatement);
 
 var AST_ForIn = DEFNODE("ForIn", "init name object", {
     $documentation: "A `for ... in` statement",
@@ -249,7 +253,7 @@ var AST_ForIn = DEFNODE("ForIn", "init name object", {
             this.body._walk(visitor);
         });
     }
-}, AST_StatementWithBody);
+}, AST_IterationStatement);
 
 var AST_With = DEFNODE("With", "expression", {
     $documentation: "A `with` statement",
@@ -285,11 +289,32 @@ 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))
@@ -345,6 +370,10 @@ var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments", {
     }
 }, AST_Scope);
 
+var AST_Accessor = DEFNODE("Accessor", null, {
+    $documentation: "A setter/getter function.  The `name` property is always null."
+}, AST_Lambda);
+
 var AST_Function = DEFNODE("Function", null, {
     $documentation: "A function expression"
 }, AST_Lambda);
@@ -727,7 +756,7 @@ var AST_Object = DEFNODE("Object", "properties", {
 var AST_ObjectProperty = DEFNODE("ObjectProperty", "key value", {
     $documentation: "Base class for literal object properties",
     $propdoc: {
-        key: "[string] the property name; it's always a plain string in our AST, no matter if it was a string, number or identifier in original code",
+        key: "[string] the property name converted to a string for ObjectKeyVal.  For setters and getters this is an arbitrary AST_Node.",
         value: "[AST_Node] property value.  For setters and getters this is an AST_Function."
     },
     _walk: function(visitor) {
@@ -758,6 +787,10 @@ var AST_Symbol = DEFNODE("Symbol", "scope name thedef", {
     $documentation: "Base class for all symbols",
 });
 
+var AST_SymbolAccessor = DEFNODE("SymbolAccessor", null, {
+    $documentation: "The name of a property accessor (setter/getter function)"
+}, AST_Symbol);
+
 var AST_SymbolDeclaration = DEFNODE("SymbolDeclaration", "init", {
     $documentation: "A declaration symbol (symbol in var/const, function name or argument, symbol in catch)",
     $propdoc: {
@@ -792,7 +825,11 @@ var AST_SymbolCatch = DEFNODE("SymbolCatch", null, {
 var AST_Label = DEFNODE("Label", "references", {
     $documentation: "Symbol naming a label (declaration)",
     $propdoc: {
-        references: "[AST_LabelRef*] a list of nodes referring to this label"
+        references: "[AST_LoopControl*] a list of nodes referring to this label"
+    },
+    initialize: function() {
+        this.references = [];
+        this.thedef = this;
     }
 }, AST_Symbol);
 
@@ -802,7 +839,7 @@ var AST_SymbolRef = DEFNODE("SymbolRef", null, {
 
 var AST_LabelRef = DEFNODE("LabelRef", null, {
     $documentation: "Reference to a label symbol",
-}, AST_SymbolRef);
+}, AST_Symbol);
 
 var AST_This = DEFNODE("This", null, {
     $documentation: "The `this` symbol",
@@ -855,6 +892,11 @@ 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
@@ -911,6 +953,9 @@ TreeWalker.prototype = {
             if (x instanceof type) return x;
         }
     },
+    has_directive: function(type) {
+        return this.find_parent(AST_Scope).has_directive(type);
+    },
     in_boolean_context: function() {
         var stack = this.stack;
         var i = stack.length, self = stack[--i];
@@ -931,21 +976,15 @@ TreeWalker.prototype = {
     },
     loopcontrol_target: function(label) {
         var stack = this.stack;
-        if (label) {
-            for (var i = stack.length; --i >= 0;) {
-                var x = stack[i];
-                if (x instanceof AST_LabeledStatement && x.label.name == label.name) {
-                    return x.body;
-                }
-            }
-        } else {
-            for (var i = stack.length; --i >= 0;) {
-                var x = stack[i];
-                if (x instanceof AST_Switch
-                    || x instanceof AST_For
-                    || x instanceof AST_ForIn
-                    || x instanceof AST_DWLoop) return x;
+        if (label) for (var i = stack.length; --i >= 0;) {
+            var x = stack[i];
+            if (x instanceof AST_LabeledStatement && x.label.name == label.name) {
+                return x.body;
             }
+        } else for (var i = stack.length; --i >= 0;) {
+            var x = stack[i];
+            if (x instanceof AST_Switch || x instanceof AST_IterationStatement)
+                return x;
         }
     }
 };

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

@@ -54,12 +54,14 @@ function OutputStream(options) {
         inline_script : false,
         width         : 80,
         max_line_len  : 32000,
-        ie_proof      : true,
         beautify      : false,
         source_map    : null,
         bracketize    : false,
         semicolons    : true,
-        comments      : false
+        comments      : false,
+        preserve_line : false,
+        screw_ie8     : false,
+        preamble      : null,
     }, true);
 
     var indentation = 0;
@@ -68,11 +70,16 @@ 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;
+            }
         });
     };
 
@@ -89,7 +96,7 @@ function OutputStream(options) {
               case "\u2029": return "\\u2029";
               case '"': ++dq; return '"';
               case "'": ++sq; return "'";
-              case "\0": return "\\0";
+              case "\0": return "\\x00";
             }
             return s;
         });
@@ -108,7 +115,7 @@ 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;
     };
 
@@ -137,7 +144,7 @@ function OutputStream(options) {
         str = String(str);
         var ch = str.charAt(0);
         if (might_need_semicolon) {
-            if (";}".indexOf(ch) < 0 && !/[;]$/.test(last)) {
+            if ((!ch || ";}".indexOf(ch) < 0) && !/[;]$/.test(last)) {
                 if (options.semicolons || requireSemicolonChars(ch)) {
                     OUTPUT += ";";
                     current_col++;
@@ -154,6 +161,18 @@ function OutputStream(options) {
             might_need_semicolon = false;
             maybe_newline();
         }
+
+        if (!options.beautify && options.preserve_line && stack[stack.length - 1]) {
+            var target_line = stack[stack.length - 1].start.line;
+            while (current_line < target_line) {
+                OUTPUT += "\n";
+                current_pos++;
+                current_line++;
+                current_col = 0;
+                might_need_space = false;
+            }
+        }
+
         if (might_need_space) {
             var prev = last_char();
             if ((is_identifier_char(prev)
@@ -281,6 +300,10 @@ function OutputStream(options) {
         return OUTPUT;
     };
 
+    if (options.preamble) {
+        print(options.preamble.replace(/\r\n?|[\n\u2028\u2029]|\s*$/g, "\n"));
+    }
+
     var stack = [];
     return {
         get             : get,
@@ -327,24 +350,25 @@ 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 {
-                self.add_comments(stream);
-                self.add_source_map(stream);
-                generator(self, stream);
-            }
-            stream.pop_node();
-        });
+        nodetype.DEFMETHOD("_codegen", generator);
     };
 
+    AST_Node.DEFMETHOD("print", function(stream, force_parens){
+        var self = this, generator = self._codegen;
+        function doit() {
+            self.add_comments(stream);
+            self.add_source_map(stream);
+            generator(self, stream);
+        }
+        stream.push_node(self);
+        if (force_parens || self.needs_parens(stream)) {
+            stream.with_parens(doit);
+        } else {
+            doit();
+        }
+        stream.pop_node();
+    });
+
     AST_Node.DEFMETHOD("print_to_string", function(options){
         var s = OutputStream(options);
         this.print(s);
@@ -359,7 +383,18 @@ function OutputStream(options) {
             var start = self.start;
             if (start && !start._comments_dumped) {
                 start._comments_dumped = true;
-                var comments = start.comments_before;
+                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
+                    && 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);
@@ -370,7 +405,7 @@ function OutputStream(options) {
                     });
                 }
                 comments.forEach(function(c){
-                    if (c.type == "comment1") {
+                    if (/comment[134]/.test(c.type)) {
                         output.print("//" + c.value + "\n");
                         output.indent();
                     }
@@ -410,6 +445,11 @@ function OutputStream(options) {
         return first_in_statement(output);
     });
 
+    PARENS(AST_Unary, function(output){
+        var p = output.parent();
+        return p instanceof AST_PropAccess && p.expression === this;
+    });
+
     PARENS(AST_Seq, function(output){
         var p = output.parent();
         return p instanceof AST_Call             // (foo, bar)() or foo(1, (2, 3), 4)
@@ -441,32 +481,63 @@ function OutputStream(options) {
             var so = this.operator, sp = PRECEDENCE[so];
             if (pp > sp
                 || (pp == sp
-                    && this === p.right
-                    && !(so == po &&
-                         (so == "*" ||
-                          so == "&&" ||
-                          so == "||")))) {
+                    && this === p.right)) {
                 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){
+        var p = output.parent();
+        if (p instanceof AST_New && p.expression === this) {
+            // i.e. new (foo.bar().baz)
+            //
+            // if there's one call into this subtree, then we need
+            // parens around it too, otherwise the call will be
+            // interpreted as passing the arguments to the upper New
+            // expression.
+            try {
+                this.walk(new TreeWalker(function(node){
+                    if (node instanceof AST_Call) throw p;
+                }));
+            } catch(ex) {
+                if (ex !== p) throw ex;
+                return true;
+            }
+        }
+    });
+
+    PARENS(AST_Call, function(output){
+        var p = output.parent(), p1;
+        if (p instanceof AST_New && p.expression === this)
+            return true;
+
+        // workaround for Safari bug.
+        // https://bugs.webkit.org/show_bug.cgi?id=123506
+        return this.expression instanceof AST_Function
+            && p instanceof AST_PropAccess
+            && p.expression === this
+            && (p1 = output.parent(1)) instanceof AST_Assign
+            && p1.left === p;
     });
 
     PARENS(AST_New, function(output){
         var p = output.parent();
-        // (new Date).getTime();
-        if (p instanceof AST_Dot && no_constructor_parens(this, output))
+        if (no_constructor_parens(this, output)
+            && (p instanceof AST_PropAccess // (new Date).getTime(), (new Date)["getTime"]()
+                || p instanceof AST_Call && p.expression === this)) // (new foo)(bar)
+            return true;
+    });
+
+    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;
     });
 
@@ -529,6 +600,7 @@ function OutputStream(options) {
     });
     DEFPRINT(AST_Toplevel, function(self, output){
         display_body(self.body, true, output);
+        output.print("");
     });
     DEFPRINT(AST_LabeledStatement, function(self, output){
         self.label.print(output);
@@ -577,7 +649,11 @@ 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 {
@@ -689,9 +765,9 @@ 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")) {
+            && !output.option("screw_ie8")) {
             // https://github.com/mishoo/UglifyJS/issues/#issue/57 IE
             // croaks with "syntax error" on code like this: if (foo)
             // do ... while(cond); else ...  we need block brackets
@@ -713,7 +789,7 @@ function OutputStream(options) {
             }
             else break;
         }
-        self.body.print(output);
+        force_statement(self.body, output);
     };
     DEFPRINT(AST_If, function(self, output){
         output.print("if");
@@ -821,13 +897,32 @@ 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);
         }
     });
 
@@ -846,7 +941,7 @@ 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){
@@ -874,7 +969,7 @@ 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(".");
             }
@@ -905,7 +1000,18 @@ function OutputStream(options) {
         self.left.print(output);
         output.space();
         output.print(self.operator);
-        output.space();
+        if (self.operator == "<"
+            && self.right instanceof AST_UnaryPrefix
+            && self.right.operator == "!"
+            && self.right.expression instanceof AST_UnaryPrefix
+            && self.right.expression.operator == "--") {
+            // space is mandatory to avoid outputting <!--
+            // http://javascript.spec.whatwg.org/#comment-syntax
+            output.print(" ");
+        } else {
+            // the space is optional depending on "beautify"
+            output.space();
+        }
         self.right.print(output);
     });
     DEFPRINT(AST_Conditional, function(self, output){
@@ -926,8 +1032,12 @@ 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 the final element is a hole, we need to make sure it
+                // doesn't look like a trailing comma, by inserting an actual
+                // trailing comma.
+                if (i === len - 1 && exp instanceof AST_Hole)
+                  output.comma();
             });
             if (len > 0) output.space();
         });
@@ -949,26 +1059,30 @@ 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)
                    && parseFloat(key) >= 0) {
             output.print(make_num(key));
-        } else if (!is_identifier(key)) {
-            output.print_string(key);
-        } else {
+        } else if (RESERVED_WORDS(key) ? output.option("screw_ie8") : is_identifier_string(key)) {
             output.print_name(key);
+        } else {
+            output.print_string(key);
         }
         output.colon();
         self.value.print(output);
     });
     DEFPRINT(AST_ObjectSetter, function(self, output){
         output.print("set");
+        output.space();
+        self.key.print(output);
         self.value._do_print(output, true);
     });
     DEFPRINT(AST_ObjectGetter, function(self, output){
         output.print("get");
+        output.space();
+        self.key.print(output);
         self.value._do_print(output, true);
     });
     DEFPRINT(AST_Symbol, function(self, output){
@@ -978,6 +1092,7 @@ 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");
     });
@@ -1001,6 +1116,9 @@ 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) {
@@ -1031,7 +1149,7 @@ function OutputStream(options) {
             if (p instanceof AST_Statement && p.body === node)
                 return true;
             if ((p instanceof AST_Seq           && p.car === node        ) ||
-                (p instanceof AST_Call          && p.expression === node ) ||
+                (p instanceof AST_Call          && p.expression === node && !(p instanceof AST_New) ) ||
                 (p instanceof AST_Dot           && p.expression === node ) ||
                 (p instanceof AST_Sub           && p.expression === node ) ||
                 (p instanceof AST_Conditional   && p.condition === node  ) ||

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 +167,17 @@ function is_identifier_char(ch) {
     ;
 };
 
+function is_identifier_string(str){
+    var i = str.length;
+    if (i == 0) return false;
+    if (!is_identifier_start(str.charCodeAt(0))) return false;
+    while (--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 +201,6 @@ 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);
 };
 
@@ -205,7 +210,7 @@ function is_token(token, type, val) {
 
 var EX_EOF = {};
 
-function tokenizer($TEXT, filename) {
+function tokenizer($TEXT, filename, html5_comments) {
 
     var S = {
         text            : $TEXT.replace(/\r\n?|[\n\u2028\u2029]/g, "\n").replace(/\uFEFF/g, ''),
@@ -237,6 +242,14 @@ function tokenizer($TEXT, filename) {
         return ch;
     };
 
+    function forward(i) {
+        while (i-- > 0) next();
+    };
+
+    function looking_at(str) {
+        return S.text.substr(S.pos, str.length) == str;
+    };
+
     function find(what, signal_eof) {
         var pos = S.text.indexOf(what, S.pos);
         if (signal_eof && pos == -1) throw EX_EOF;
@@ -249,10 +262,12 @@ function tokenizer($TEXT, filename) {
         S.tokpos = S.pos;
     };
 
+    var prev_was_dot = false;
     function token(type, value, is_comment) {
-        S.regex_allowed = ((type == "operator" && !UNARY_POSTFIX[value]) ||
+        S.regex_allowed = ((type == "operator" && !UNARY_POSTFIX(value)) ||
                            (type == "keyword" && KEYWORDS_BEFORE_EXPRESSION(value)) ||
                            (type == "punc" && PUNC_BEFORE_EXPRESSION(value)));
+        prev_was_dot = (type == "punc" && value == ".");
         var ret = {
             type   : type,
             value  : value,
@@ -374,8 +389,8 @@ function tokenizer($TEXT, filename) {
         return token("string", ret);
     });
 
-    function read_line_comment() {
-        next();
+    function skip_line_comment(type) {
+        var regex_allowed = S.regex_allowed;
         var i = find("\n"), ret;
         if (i == -1) {
             ret = S.text.substr(S.pos);
@@ -384,11 +399,13 @@ function tokenizer($TEXT, filename) {
             ret = S.text.substring(S.pos, i);
             S.pos = i;
         }
-        return token("comment1", ret, true);
+        S.comments_before.push(token(type, ret, true));
+        S.regex_allowed = regex_allowed;
+        return next_token();
     };
 
-    var read_multiline_comment = with_eof_error("Unterminated multiline comment", function(){
-        next();
+    var skip_multiline_comment = with_eof_error("Unterminated multiline comment", function(){
+        var regex_allowed = S.regex_allowed;
         var i = find("*/", true);
         var text = S.text.substring(S.pos, i);
         var a = text.split("\n"), n = a.length;
@@ -398,8 +415,11 @@ function tokenizer($TEXT, filename) {
         if (n > 1) S.col = a[n - 1].length;
         else S.col += a[n - 1].length;
         S.col += 2;
-        S.newline_before = S.newline_before || text.indexOf("\n") >= 0;
-        return token("comment2", text, true);
+        var nlb = S.newline_before = S.newline_before || text.indexOf("\n") >= 0;
+        S.comments_before.push(token("comment2", text, true));
+        S.regex_allowed = regex_allowed;
+        S.newline_before = nlb;
+        return next_token();
     });
 
     function read_name() {
@@ -463,16 +483,13 @@ function tokenizer($TEXT, filename) {
 
     function handle_slash() {
         next();
-        var regex_allowed = S.regex_allowed;
         switch (peek()) {
           case "/":
-            S.comments_before.push(read_line_comment());
-            S.regex_allowed = regex_allowed;
-            return next_token();
+            next();
+            return skip_line_comment("comment1");
           case "*":
-            S.comments_before.push(read_multiline_comment());
-            S.regex_allowed = regex_allowed;
-            return next_token();
+            next();
+            return skip_multiline_comment();
         }
         return S.regex_allowed ? read_regexp("") : read_operator("/");
     };
@@ -486,6 +503,7 @@ function tokenizer($TEXT, filename) {
 
     function read_word() {
         var word = read_name();
+        if (prev_was_dot) return token("name", word);
         return KEYWORDS_ATOM(word) ? token("atom", word)
             : !KEYWORDS(word) ? token("name", word)
             : OPERATORS(word) ? token("operator", word)
@@ -508,6 +526,16 @@ function tokenizer($TEXT, filename) {
             return read_regexp(force_regexp);
         skip_whitespace();
         start_token();
+        if (html5_comments) {
+            if (looking_at("<!--")) {
+                forward(4);
+                return skip_line_comment("comment3");
+            }
+            if (looking_at("-->") && S.newline_before) {
+                forward(3);
+                return skip_line_comment("comment4");
+            }
+        }
         var ch = peek();
         if (!ch) return token("eof");
         var code = ch.charCodeAt(0);
@@ -551,10 +579,10 @@ var UNARY_POSTFIX = makePredicate([ "--", "++" ]);
 var ASSIGNMENT = makePredicate([ "=", "+=", "-=", "/=", "*=", "%=", ">>=", "<<=", ">>>=", "|=", "^=", "&=" ]);
 
 var PRECEDENCE = (function(a, ret){
-    for (var i = 0, n = 1; i < a.length; ++i, ++n) {
+    for (var i = 0; i < a.length; ++i) {
         var b = a[i];
         for (var j = 0; j < b.length; ++j) {
-            ret[b[j]] = n;
+            ret[b[j]] = i + 1;
         }
     }
     return ret;
@@ -583,13 +611,18 @@ var ATOMIC_START_TOKEN = array_to_hash([ "atom", "num", "string", "regexp", "nam
 function parse($TEXT, options) {
 
     options = defaults(options, {
-        strict   : false,
-        filename : null,
-        toplevel : null
+        strict         : false,
+        filename       : null,
+        toplevel       : null,
+        expression     : false,
+        html5_comments : true,
     });
 
     var S = {
-        input         : typeof $TEXT == "string" ? tokenizer($TEXT, options.filename) : $TEXT,
+        input         : (typeof $TEXT == "string"
+                         ? tokenizer($TEXT, options.filename,
+                                     options.html5_comments)
+                         : $TEXT),
         token         : null,
         prev          : null,
         peeked        : null,
@@ -682,12 +715,16 @@ function parse($TEXT, options) {
         };
     };
 
-    var statement = embed_tokens(function() {
-        var tmp;
+    function handle_regexp() {
         if (is("operator", "/") || is("operator", "/=")) {
             S.peeked = null;
             S.token = S.input(S.token.value.substr(1)); // force regexp
         }
+    };
+
+    var statement = embed_tokens(function() {
+        var tmp;
+        handle_regexp();
         switch (S.token.type) {
           case "string":
             var dir = S.in_directives, stat = simple_statement();
@@ -752,7 +789,7 @@ function parse($TEXT, options) {
                 return for_();
 
               case "function":
-                return function_(true);
+                return function_(AST_Defun);
 
               case "if":
                 return if_();
@@ -815,6 +852,18 @@ function parse($TEXT, options) {
         S.labels.push(label);
         var stat = statement();
         S.labels.pop();
+        if (!(stat instanceof AST_IterationStatement)) {
+            // check for `continue` that refers to this label.
+            // those should be reported as syntax errors.
+            // https://github.com/mishoo/UglifyJS2/issues/287
+            label.references.forEach(function(ref){
+                if (ref instanceof AST_Continue) {
+                    ref = ref.label.start;
+                    croak("Continue label `" + label.name + "` refers to non-IterationStatement.",
+                          ref.line, ref.col, ref.pos);
+                }
+            });
+        }
         return new AST_LabeledStatement({ body: stat, label: label });
     };
 
@@ -823,18 +872,22 @@ function parse($TEXT, options) {
     };
 
     function break_cont(type) {
-        var label = null;
+        var label = null, ldef;
         if (!can_insert_semicolon()) {
             label = as_symbol(AST_LabelRef, true);
         }
         if (label != null) {
-            if (!find_if(function(l){ return l.name == label.name }, S.labels))
+            ldef = find_if(function(l){ return l.name == label.name }, S.labels);
+            if (!ldef)
                 croak("Undefined label " + label.name);
+            label.thedef = ldef;
         }
         else if (S.in_loop == 0)
             croak(type.TYPE + " not inside a loop or switch");
         semicolon();
-        return new type({ label: label });
+        var stat = new type({ label: label });
+        if (ldef) ldef.references.push(stat);
+        return stat;
     };
 
     function for_() {
@@ -880,14 +933,12 @@ function parse($TEXT, options) {
         });
     };
 
-    var function_ = function(in_statement, ctor) {
-        var name = is("name") ? as_symbol(in_statement
-                                          ? AST_SymbolDefun
-                                          : AST_SymbolLambda) : null;
+    var function_ = function(ctor) {
+        var in_statement = ctor === AST_Defun;
+        var name = is("name") ? as_symbol(in_statement ? AST_SymbolDefun : AST_SymbolLambda) : null;
         if (in_statement && !name)
             unexpected();
         expect("(");
-        if (!ctor) ctor = in_statement ? AST_Defun : AST_Function;
         return new ctor({
             name: name,
             argnames: (function(first, a){
@@ -1058,7 +1109,9 @@ function parse($TEXT, options) {
         var tok = S.token, ret;
         switch (tok.type) {
           case "name":
-            return as_symbol(AST_SymbolRef);
+          case "keyword":
+            ret = _make_symbol(AST_SymbolRef);
+            break;
           case "num":
             ret = new AST_Number({ start: tok, end: tok, value: tok.value });
             break;
@@ -1109,7 +1162,7 @@ function parse($TEXT, options) {
         }
         if (is("keyword", "function")) {
             next();
-            var func = function_(false);
+            var func = function_(AST_Function);
             func.start = start;
             func.end = prev();
             return subscripts(func, allow_calls);
@@ -1126,7 +1179,7 @@ function parse($TEXT, options) {
             if (first) first = false; else expect(",");
             if (allow_trailing_comma && is("punc", closing)) break;
             if (is("punc", ",") && allow_empty) {
-                a.push(new AST_Undefined({ start: S.token, end: S.token }));
+                a.push(new AST_Hole({ start: S.token, end: S.token }));
             } else {
                 a.push(expression(false));
             }
@@ -1157,8 +1210,8 @@ function parse($TEXT, options) {
                 if (name == "get") {
                     a.push(new AST_ObjectGetter({
                         start : start,
-                        key   : name,
-                        value : function_(false, AST_Lambda),
+                        key   : as_atom_node(),
+                        value : function_(AST_Accessor),
                         end   : prev()
                     }));
                     continue;
@@ -1166,8 +1219,8 @@ function parse($TEXT, options) {
                 if (name == "set") {
                     a.push(new AST_ObjectSetter({
                         start : start,
-                        key   : name,
-                        value : function_(false, AST_Lambda),
+                        key   : as_atom_node(),
+                        value : function_(AST_Accessor),
                         end   : prev()
                     }));
                     continue;
@@ -1215,17 +1268,21 @@ function parse($TEXT, options) {
         }
     };
 
+    function _make_symbol(type) {
+        var name = S.token.value;
+        return new (name == "this" ? AST_This : type)({
+            name  : String(name),
+            start : S.token,
+            end   : S.token
+        });
+    };
+
     function as_symbol(type, noerror) {
         if (!is("name")) {
             if (!noerror) croak("Name expected");
             return null;
         }
-        var name = S.token.value;
-        var sym = new (name == "this" ? AST_This : type)({
-            name  : String(S.token.value),
-            start : S.token,
-            end   : S.token
-        });
+        var sym = _make_symbol(type);
         next();
         return sym;
     };
@@ -1268,6 +1325,7 @@ function parse($TEXT, options) {
         var start = S.token;
         if (is("operator") && UNARY_PREFIX(start.value)) {
             next();
+            handle_regexp();
             var ex = make_unary(AST_UnaryPrefix, start.value, maybe_unary(allow_calls));
             ex.start = start;
             ex.end = prev();
@@ -1331,15 +1389,8 @@ function parse($TEXT, options) {
 
     function is_assignable(expr) {
         if (!options.strict) return true;
-        switch (expr[0]+"") {
-          case "dot":
-          case "sub":
-          case "new":
-          case "call":
-            return true;
-          case "name":
-            return expr[1] != "this";
-        }
+        if (expr instanceof AST_This) return false;
+        return (expr instanceof AST_PropAccess || expr instanceof AST_Symbol);
     };
 
     var maybe_assign = function(no_in) {
@@ -1353,7 +1404,7 @@ function parse($TEXT, options) {
                     left     : left,
                     operator : val,
                     right    : maybe_assign(no_in),
-                    end      : peek()
+                    end      : prev()
                 });
             }
             croak("Invalid assignment");
@@ -1383,6 +1434,10 @@ function parse($TEXT, options) {
         return ret;
     };
 
+    if (options.expression) {
+        return expression(true);
+    }
+
     return (function(){
         var start = S.token;
         var body = [];

lib/scope.js

@@ -43,7 +43,7 @@
 
 "use strict";
 
-function SymbolDef(scope, orig) {
+function SymbolDef(scope, index, orig) {
     this.name = orig.name;
     this.orig = [ orig ];
     this.scope = scope;
@@ -52,15 +52,22 @@ function SymbolDef(scope, orig) {
     this.mangled_name = null;
     this.undeclared = false;
     this.constant = false;
+    this.index = index;
 };
 
 SymbolDef.prototype = {
-    unmangleable: function() {
-        return this.global || this.undeclared || this.scope.uses_eval || this.scope.uses_with;
+    unmangleable: function(options) {
+        return (this.global && !(options && options.toplevel))
+            || this.undeclared
+            || (!(options && options.eval) && (this.scope.uses_eval || this.scope.uses_with));
     },
-    mangle: function() {
-        if (!this.mangled_name && !this.unmangleable())
-            this.mangled_name = this.scope.next_mangled();
+    mangle: function(options) {
+        if (!this.mangled_name && !this.unmangleable(options)) {
+            var s = this.scope;
+            if (!options.screw_ie8 && this.orig[0] instanceof AST_SymbolLambda)
+                s = s.parent_scope;
+            this.mangled_name = s.next_mangled(options, this);
+        }
     }
 };
 
@@ -75,14 +82,16 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
     // pass 1: setup scope chaining and handle definitions
     var self = this;
     var scope = self.parent_scope = null;
-    var labels = Object.create(null);
+    var nesting = 0;
     var tw = new TreeWalker(function(node, descend){
         if (node instanceof AST_Scope) {
-            node.init_scope_vars();
+            node.init_scope_vars(nesting);
             var save_scope = node.parent_scope = scope;
+            ++nesting;
             scope = node;
             descend();
             scope = save_scope;
+            --nesting;
             return true;        // don't descend again in TreeWalker
         }
         if (node instanceof AST_Directive) {
@@ -95,35 +104,11 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
                 s.uses_with = true;
             return;
         }
-        if (node instanceof AST_LabeledStatement) {
-            var l = node.label;
-            if (labels[l.name])
-                throw new Error(string_template("Label {name} defined twice", l));
-            labels[l.name] = l;
-            descend();
-            delete labels[l.name];
-            return true;        // no descend again
-        }
-        if (node instanceof AST_SymbolDeclaration) {
-            node.init_scope_vars();
-        }
         if (node instanceof AST_Symbol) {
             node.scope = scope;
         }
-        if (node instanceof AST_Label) {
-            node.thedef = node;
-            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
@@ -132,14 +117,12 @@ 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
@@ -150,21 +133,12 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             // identifier in the enclosing scope)
             scope.def_variable(node);
         }
-        if (node instanceof AST_LabelRef) {
-            var sym = labels[node.name];
-            if (!sym) throw new Error(string_template("Undefined label {name} [{line},{col}]", {
-                name: node.name,
-                line: node.start.line,
-                col: node.start.col
-            }));
-            node.thedef = sym;
-        }
     });
     self.walk(tw);
 
     // pass 2: find back references and eval
     var func = null;
-    var globals = self.globals = Object.create(null);
+    var globals = self.globals = new Dictionary();
     var tw = new TreeWalker(function(node, descend){
         if (node instanceof AST_Lambda) {
             var prev_func = func;
@@ -173,28 +147,25 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             func = prev_func;
             return true;
         }
-        if (node instanceof AST_LabelRef) {
-            node.reference();
-            return true;
-        }
         if (node instanceof AST_SymbolRef) {
             var name = node.name;
             var sym = node.scope.find_variable(name);
             if (!sym) {
                 var g;
-                if (globals[name]) {
-                    g = globals[name];
+                if (globals.has(name)) {
+                    g = globals.get(name);
                 } else {
-                    g = new SymbolDef(self, node);
+                    g = new SymbolDef(self, globals.size(), node);
                     g.undeclared = true;
-                    globals[name] = g;
+                    g.global = true;
+                    globals.set(name, g);
                 }
                 node.thedef = g;
                 if (name == "eval" && tw.parent() instanceof AST_Call) {
                     for (var s = node.scope; s && !s.uses_eval; s = s.parent_scope)
                         s.uses_eval = true;
                 }
-                if (name == "arguments") {
+                if (func && name == "arguments") {
                     func.uses_arguments = true;
                 }
             } else {
@@ -207,15 +178,16 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
     self.walk(tw);
 });
 
-AST_Scope.DEFMETHOD("init_scope_vars", function(){
+AST_Scope.DEFMETHOD("init_scope_vars", function(nesting){
     this.directives = [];     // contains the directives defined in this scope, i.e. "use strict"
-    this.variables = Object.create(null); // map name to AST_SymbolVar (variables defined in this scope; includes functions)
-    this.functions = Object.create(null); // map name to AST_SymbolDefun (functions defined in this scope)
+    this.variables = new Dictionary(); // map name to AST_SymbolVar (variables defined in this scope; includes functions)
+    this.functions = new Dictionary(); // map name to AST_SymbolDefun (functions defined in this scope)
     this.uses_with = false;   // will be set to true if this or some nested scope uses the `with` statement
     this.uses_eval = false;   // will be set to true if this or nested scope uses the global `eval`
     this.parent_scope = null; // the parent scope
     this.enclosed = [];       // a list of variables from this or outer scope(s) that are referenced from this or inner scopes
     this.cname = -1;          // the current index for mangling functions/variables
+    this.nesting = nesting;   // the nesting level of this scope (0 means toplevel)
 });
 
 AST_Scope.DEFMETHOD("strict", function(){
@@ -223,7 +195,7 @@ AST_Scope.DEFMETHOD("strict", function(){
 });
 
 AST_Lambda.DEFMETHOD("init_scope_vars", function(){
-    AST_Scope.prototype.init_scope_vars.call(this);
+    AST_Scope.prototype.init_scope_vars.apply(this, arguments);
     this.uses_arguments = false;
 });
 
@@ -236,23 +208,12 @@ AST_SymbolRef.DEFMETHOD("reference", function() {
         if (s === def.scope) break;
         s = s.parent_scope;
     }
-});
-
-AST_SymbolDeclaration.DEFMETHOD("init_scope_vars", function(){
-    this.init = [];
-});
-
-AST_Label.DEFMETHOD("init_scope_vars", function(){
-    this.references = [];
-});
-
-AST_LabelRef.DEFMETHOD("reference", function(){
-    this.thedef.references.push(this);
+    this.frame = this.scope.nesting - def.scope.nesting;
 });
 
 AST_Scope.DEFMETHOD("find_variable", function(name){
     if (name instanceof AST_Symbol) name = name.name;
-    return this.variables[name]
+    return this.variables.get(name)
         || (this.parent_scope && this.parent_scope.find_variable(name));
 });
 
@@ -262,46 +223,64 @@ AST_Scope.DEFMETHOD("has_directive", function(value){
 });
 
 AST_Scope.DEFMETHOD("def_function", function(symbol){
-    this.functions[symbol.name] = this.def_variable(symbol);
+    this.functions.set(symbol.name, this.def_variable(symbol));
 });
 
 AST_Scope.DEFMETHOD("def_variable", function(symbol){
     var def;
-    if (!this.variables[symbol.name]) {
-        def = new SymbolDef(this, symbol);
-        this.variables[symbol.name] = def;
+    if (!this.variables.has(symbol.name)) {
+        def = new SymbolDef(this, this.variables.size(), symbol);
+        this.variables.set(symbol.name, def);
         def.global = !this.parent_scope;
     } else {
-        def = this.variables[symbol.name];
+        def = this.variables.get(symbol.name);
         def.orig.push(symbol);
     }
     return symbol.thedef = def;
 });
 
-AST_Scope.DEFMETHOD("next_mangled", function(){
-    var ext = this.enclosed, n = ext.length;
+AST_Scope.DEFMETHOD("next_mangled", function(options){
+    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() && sym.name);
+            var name = sym.mangled_name || (sym.unmangleable(options) && sym.name);
             if (m == name) continue out;
         }
         return m;
     }
 });
 
+AST_Function.DEFMETHOD("next_mangled", function(options, def){
+    // #179, #326
+    // in Safari strict mode, something like (function x(x){...}) is a syntax error;
+    // a function expression's argument cannot shadow the function expression's name
+
+    var tricky_def = def.orig[0] instanceof AST_SymbolFunarg && this.name && this.name.definition();
+    while (true) {
+        var name = AST_Lambda.prototype.next_mangled.call(this, options, def);
+        if (!(tricky_def && tricky_def.mangled_name == name))
+            return name;
+    }
+});
+
 AST_Scope.DEFMETHOD("references", function(sym){
     if (sym instanceof AST_Symbol) sym = sym.definition();
     return this.enclosed.indexOf(sym) < 0 ? null : sym;
 });
 
-AST_Symbol.DEFMETHOD("unmangleable", function(){
-    return this.definition().unmangleable();
+AST_Symbol.DEFMETHOD("unmangleable", function(options){
+    return this.definition().unmangleable(options);
+});
+
+// property accessors are not mangleable
+AST_SymbolAccessor.DEFMETHOD("unmangleable", function(){
+    return true;
 });
 
 // labels are always mangleable
@@ -334,10 +313,18 @@ AST_Symbol.DEFMETHOD("global", function(){
     return this.definition().global;
 });
 
-AST_Toplevel.DEFMETHOD("mangle_names", function(options){
-    options = defaults(options, {
-        except : []
+AST_Toplevel.DEFMETHOD("_default_mangler_options", function(options){
+    return defaults(options, {
+        except   : [],
+        eval     : false,
+        sort     : false,
+        toplevel : false,
+        screw_ie8 : false
     });
+});
+
+AST_Toplevel.DEFMETHOD("mangle_names", function(options){
+    options = this._default_mangler_options(options);
     // We only need to mangle declaration nodes.  Special logic wired
     // into the code generator will display the mangled name if it's
     // present (and for AST_SymbolRef-s it'll use the mangled name of
@@ -353,17 +340,16 @@ 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 is_setget = p instanceof AST_ObjectSetter || p instanceof AST_ObjectGetter;
-            var a = node.variables;
-            for (var i in a) {
-                var symbol = a[i];
-                if (!(is_setget && symbol instanceof AST_SymbolLambda)) {
-                    if (options.except.indexOf(symbol.name) < 0) {
-                        to_mangle.push(symbol);
-                    }
+            var p = tw.parent(), a = [];
+            node.variables.each(function(symbol){
+                if (options.except.indexOf(symbol.name) < 0) {
+                    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) {
@@ -377,7 +363,8 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options){
     to_mangle.forEach(function(def){ def.mangle(options) });
 });
 
-AST_Toplevel.DEFMETHOD("compute_char_frequency", function(){
+AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options){
+    options = this._default_mangler_options(options);
     var tw = new TreeWalker(function(node){
         if (node instanceof AST_Constant)
             base54.consider(node.print_to_string());
@@ -435,7 +422,7 @@ AST_Toplevel.DEFMETHOD("compute_char_frequency", function(){
             base54.consider("catch");
         else if (node instanceof AST_Finally)
             base54.consider("finally");
-        else if (node instanceof AST_Symbol && node.unmangleable())
+        else if (node instanceof AST_Symbol && node.unmangleable(options))
             base54.consider(node.name);
         else if (node instanceof AST_Unary || node instanceof AST_Binary)
             base54.consider(node.operator);

lib/transform.js

@@ -44,7 +44,6 @@
 "use strict";
 
 // Tree transformer helpers.
-// XXX: eventually I should refactor the compressor to use this infrastructure.
 
 function TreeTransformer(before, after) {
     TreeWalker.call(this);
@@ -65,7 +64,7 @@ TreeTransformer.prototype = new TreeWalker;
                     x = this;
                     descend(x, tw);
                 } else {
-                    tw.stack[tw.stack - 1] = x = this.clone();
+                    tw.stack[tw.stack.length - 1] = x = this.clone();
                     descend(x, tw);
                     y = tw.after(x, in_list);
                     if (y !== undefined) x = y;
@@ -160,6 +159,7 @@ TreeTransformer.prototype = new TreeWalker;
     });
 
     _(AST_VarDef, function(self, tw){
+        self.name = self.name.transform(tw);
         if (self.value) self.value = self.value.transform(tw);
     });
 

lib/utils.js

@@ -244,3 +244,52 @@ function makePredicate(words) {
     }
     return new Function("str", f);
 };
+
+function all(array, predicate) {
+    for (var i = array.length; --i >= 0;)
+        if (!predicate(array[i]))
+            return false;
+    return true;
+};
+
+function Dictionary() {
+    this._values = Object.create(null);
+    this._size = 0;
+};
+Dictionary.prototype = {
+    set: function(key, val) {
+        if (!this.has(key)) ++this._size;
+        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)) {
+            --this._size;
+            delete this._values["$" + key];
+        }
+        return this;
+    },
+    has: function(key) { return ("$" + key) in this._values },
+    each: function(f) {
+        for (var i in this._values)
+            f(this._values[i], i.substr(1));
+    },
+    size: function() {
+        return this._size;
+    },
+    map: function(f) {
+        var ret = [];
+        for (var i in this._values)
+            ret.push(f(this._values[i], i.substr(1)));
+        return ret;
+    }
+};

package.json

@@ -1,25 +1,30 @@
 {
-    "name": "uglify-js2",
+    "name": "uglify-js",
     "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
     "homepage": "http://lisperator.net/uglifyjs",
     "main": "tools/node.js",
-    "version": "2.1.5",
+    "version": "2.4.3",
     "engines": { "node" : ">=0.4.0" },
     "maintainers": [{
         "name": "Mihai Bazon",
         "email": "mihai.bazon@gmail.com",
         "web": "http://lisperator.net/"
     }],
-    "repositories": [{
+    "repository": {
         "type": "git",
         "url": "https://github.com/mishoo/UglifyJS2.git"
-    }],
+    },
     "dependencies": {
-        "source-map" : "*",
-        "optimist"   : "*"
+        "async"      : "~0.2.6",
+        "source-map" : "~0.1.7",
+        "optimist"   : "~0.3.5",
+        "uglify-to-browserify": "~1.0.0"
+    },
+    "browserify": {
+        "transform": [ "uglify-to-browserify" ]
     },
     "bin": {
-        "uglifyjs2" : "bin/uglifyjs2"
+        "uglifyjs" : "bin/uglifyjs"
     },
     "scripts": {"test": "node test/run-tests.js"}
 }

test/compress/arrays.js

@@ -0,0 +1,74 @@
+holes_and_undefined: {
+    input: {
+        w = [1,,];
+        x = [1, 2, undefined];
+        y = [1, , 2, ];
+        z = [1, undefined, 3];
+    }
+    expect: {
+        w=[1,,];
+        x=[1,2,void 0];
+        y=[1,,2];
+        z=[1,void 0,3];
+    }
+}
+
+constant_join: {
+    options = {
+        unsafe   : true,
+        evaluate : true
+    };
+    input: {
+        var a = [ "foo", "bar", "baz" ].join("");
+        var a1 = [ "foo", "bar", "baz" ].join();
+        var b = [ "foo", 1, 2, 3, "bar" ].join("");
+        var c = [ boo(), "foo", 1, 2, 3, "bar", bar() ].join("");
+        var c1 = [ boo(), bar(), "foo", 1, 2, 3, "bar", bar() ].join("");
+        var c2 = [ 1, 2, "foo", "bar", baz() ].join("");
+        var d = [ "foo", 1 + 2 + "bar", "baz" ].join("-");
+        var e = [].join(foo + bar);
+        var f = [].join("");
+        var g = [].join("foo");
+    }
+    expect: {
+        var a = "foobarbaz";
+        var a1 = "foo,bar,baz";
+        var b = "foo123bar";
+        var c = boo() + "foo123bar" + bar();
+        var c1 = "" + boo() + bar() + "foo123bar" + bar();
+        var c2 = "12foobar" + baz();
+        var d = "foo-3bar-baz";
+        var e = [].join(foo + bar);
+        var f = "";
+        var g = "";
+    }
+}
+
+constant_join_2: {
+    options = {
+        unsafe   : true,
+        evaluate : true
+    };
+    input: {
+        var a = [ "foo", "bar", boo(), "baz", "x", "y" ].join("");
+        var b = [ "foo", "bar", boo(), "baz", "x", "y" ].join("-");
+        var c = [ "foo", "bar", boo(), "baz", "x", "y" ].join("really-long-separator");
+        var d = [ "foo", "bar", boo(),
+                  [ "foo", 1, 2, 3, "bar" ].join("+"),
+                  "baz", "x", "y" ].join("-");
+        var e = [ "foo", "bar", boo(),
+                  [ "foo", 1, 2, 3, "bar" ].join("+"),
+                  "baz", "x", "y" ].join("really-long-separator");
+        var f = [ "str", "str" + variable, "foo", "bar", "moo" + foo ].join("");
+    }
+    expect: {
+        var a = "foobar" + boo() + "bazxy";
+        var b = [ "foo-bar", boo(), "baz-x-y" ].join("-");
+        var c = [ "foo", "bar", boo(), "baz", "x", "y" ].join("really-long-separator");
+        var d = [ "foo-bar", boo(), "foo+1+2+3+bar-baz-x-y" ].join("-");
+        var e = [ "foo", "bar", boo(),
+                  "foo+1+2+3+bar",
+                  "baz", "x", "y" ].join("really-long-separator");
+        var f = "strstr" + variable + "foobarmoo" + foo;
+    }
+}

test/compress/concat-strings.js

@@ -0,0 +1,22 @@
+concat_1: {
+    options = {
+        evaluate: true
+    };
+    input: {
+        var a = "foo" + "bar" + x() + "moo" + "foo" + y() + "x" + "y" + "z" + q();
+        var b = "foo" + 1 + x() + 2 + "boo";
+        var c = 1 + x() + 2 + "boo";
+
+        // this CAN'T safely be shortened to 1 + x() + "5boo"
+        var d = 1 + x() + 2 + 3 + "boo";
+
+        var e = 1 + x() + 2 + "X" + 3 + "boo";
+    }
+    expect: {
+        var a = "foobar" + x() + "moofoo" + y() + "xyz" + q();
+        var b = "foo1" + x() + "2boo";
+        var c = 1 + x() + 2 + "boo";
+        var d = 1 + x() + 2 + 3 + "boo";
+        var e = 1 + x() + 2 + "X3boo";
+    }
+}

test/compress/drop-unused.js

@@ -95,3 +95,27 @@ unused_circular_references_3: {
         }
     }
 }
+
+unused_keep_setter_arg: {
+    options = { unused: true };
+    input: {
+        var x = {
+            _foo: null,
+            set foo(val) {
+            },
+            get foo() {
+                return this._foo;
+            }
+        }
+    }
+    expect: {
+        var x = {
+            _foo: null,
+            set foo(val) {
+            },
+            get foo() {
+                return this._foo;
+            }
+        }
+    }
+}

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-126.js

@@ -0,0 +1,24 @@
+concatenate_rhs_strings: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        foo(bar() + 123 + "Hello" + "World");
+        foo(bar() + (123 + "Hello") + "World");
+        foo((bar() + 123) + "Hello" + "World");
+        foo(bar() + 123 + "Hello" + "World" + ("Foo" + "Bar"));
+        foo("Foo" + "Bar" + bar() + 123 + "Hello" + "World" + ("Foo" + "Bar"));
+        foo("Hello" + bar() + 123 + "World");
+        foo(bar() + 'Foo' + (10 + parseInt('10')));
+    }
+    expect: {
+        foo(bar() + 123 + "HelloWorld");
+        foo(bar() + "123HelloWorld");
+        foo((bar() + 123) + "HelloWorld");
+        foo(bar() + 123 + "HelloWorldFooBar");
+        foo("FooBar" + bar() + "123HelloWorldFooBar");
+        foo("Hello" + bar() + "123World");
+        foo(bar() + 'Foo' + (10 + parseInt('10')));
+    }
+}

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-267.js

@@ -0,0 +1,11 @@
+issue_267: {
+    options = { comparisons: true };
+    input: {
+        x = a % b / b * c * 2;
+        x = a % b * 2
+    }
+    expect: {
+        x = a % b / b * c * 2;
+        x = a % b * 2;
+    }
+}

test/compress/issue-269.js

@@ -0,0 +1,68 @@
+issue_269_1: {
+	options = {unsafe: true};
+	input: {
+		f(
+			String(x),
+			Number(x),
+			Boolean(x),
+
+			String(),
+			Number(),
+			Boolean()
+		);
+	}
+	expect: {
+		f(
+			x + '', +x, !!x,
+			'', 0, false
+		);
+	}
+}
+
+issue_269_dangers: {
+	options = {unsafe: true};
+	input: {
+		f(
+			String(x, x),
+			Number(x, x),
+			Boolean(x, x)
+		);
+	}
+	expect: {
+		f(String(x, x), Number(x, x), Boolean(x, x));
+	}
+}
+
+issue_269_in_scope: {
+	options = {unsafe: true};
+	input: {
+		var String, Number, Boolean;
+		f(
+			String(x),
+			Number(x, x),
+			Boolean(x)
+		);
+	}
+	expect: {
+		var String, Number, Boolean;
+		f(String(x), Number(x, x), Boolean(x));
+	}
+}
+
+strings_concat: {
+	options = {unsafe: true};
+	input: {
+		f(
+			String(x + 'str'),
+			String('str' + x),
+			String(x + 5)
+		);
+	}
+	expect: {
+		f(
+			x + 'str',
+			'str' + x,
+			x + '5'
+		);
+	}
+}

test/compress/issue-44.js

@@ -0,0 +1,31 @@
+issue_44_valid_ast_1: {
+    options = { unused: true };
+    input: {
+        function a(b) {
+            for (var i = 0, e = b.qoo(); ; i++) {}
+        }
+    }
+    expect: {
+        function a(b) {
+            var i = 0;
+            for (b.qoo(); ; i++);
+        }
+    }
+}
+
+issue_44_valid_ast_2: {
+    options = { unused: true };
+    input: {
+        function a(b) {
+            if (foo) for (var i = 0, e = b.qoo(); ; i++) {}
+        }
+    }
+    expect: {
+        function a(b) {
+            if (foo) {
+                var i = 0;
+                for (b.qoo(); ; i++);
+            }
+        }
+    }
+}

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/loops.js

@@ -0,0 +1,123 @@
+while_becomes_for: {
+    options = { loops: true };
+    input: {
+        while (foo()) bar();
+    }
+    expect: {
+        for (; foo(); ) bar();
+    }
+}
+
+drop_if_break_1: {
+    options = { loops: true };
+    input: {
+        for (;;)
+            if (foo()) break;
+    }
+    expect: {
+        for (; !foo(););
+    }
+}
+
+drop_if_break_2: {
+    options = { loops: true };
+    input: {
+        for (;bar();)
+            if (foo()) break;
+    }
+    expect: {
+        for (; bar() && !foo(););
+    }
+}
+
+drop_if_break_3: {
+    options = { loops: true };
+    input: {
+        for (;bar();) {
+            if (foo()) break;
+            stuff1();
+            stuff2();
+        }
+    }
+    expect: {
+        for (; bar() && !foo();) {
+            stuff1();
+            stuff2();
+        }
+    }
+}
+
+drop_if_break_4: {
+    options = { loops: true, sequences: true };
+    input: {
+        for (;bar();) {
+            x();
+            y();
+            if (foo()) break;
+            z();
+            k();
+        }
+    }
+    expect: {
+        for (; bar() && (x(), y(), !foo());) z(), k();
+    }
+}
+
+drop_if_else_break_1: {
+    options = { loops: true };
+    input: {
+        for (;;) if (foo()) bar(); else break;
+    }
+    expect: {
+        for (; foo(); ) bar();
+    }
+}
+
+drop_if_else_break_2: {
+    options = { loops: true };
+    input: {
+        for (;bar();) {
+            if (foo()) baz();
+            else break;
+        }
+    }
+    expect: {
+        for (; bar() && foo();) baz();
+    }
+}
+
+drop_if_else_break_3: {
+    options = { loops: true };
+    input: {
+        for (;bar();) {
+            if (foo()) baz();
+            else break;
+            stuff1();
+            stuff2();
+        }
+    }
+    expect: {
+        for (; bar() && foo();) {
+            baz();
+            stuff1();
+            stuff2();
+        }
+    }
+}
+
+drop_if_else_break_4: {
+    options = { loops: true, sequences: true };
+    input: {
+        for (;bar();) {
+            x();
+            y();
+            if (foo()) baz();
+            else break;
+            z();
+            k();
+        }
+    }
+    expect: {
+        for (; bar() && (x(), y(), foo());) baz(), z(), k();
+    }
+}

test/compress/negate-iife.js

@@ -0,0 +1,76 @@
+negate_iife_1: {
+    options = {
+        negate_iife: true
+    };
+    input: {
+        (function(){ stuff() })();
+    }
+    expect: {
+        !function(){ stuff() }();
+    }
+}
+
+negate_iife_2: {
+    options = {
+        negate_iife: true
+    };
+    input: {
+        (function(){ return {} })().x = 10; // should not transform this one
+    }
+    expect: {
+        (function(){ return {} })().x = 10;
+    }
+}
+
+negate_iife_3: {
+    options = {
+        negate_iife: true,
+    };
+    input: {
+        (function(){ return true })() ? console.log(true) : console.log(false);
+    }
+    expect: {
+        !function(){ return true }() ? console.log(false) : console.log(true);
+    }
+}
+
+negate_iife_3: {
+    options = {
+        negate_iife: true,
+        sequences: true
+    };
+    input: {
+        (function(){ return true })() ? console.log(true) : console.log(false);
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        !function(){ return true }() ? console.log(false) : console.log(true), function(){
+            console.log("something");
+        }();
+    }
+}
+
+negate_iife_4: {
+    options = {
+        negate_iife: true,
+        sequences: true,
+        conditionals: true,
+    };
+    input: {
+        if ((function(){ return true })()) {
+            console.log(true);
+        } else {
+            console.log(false);
+        }
+        (function(){
+            console.log("something");
+        })();
+    }
+    expect: {
+        !function(){ return true }() ? console.log(false) : console.log(true), function(){
+            console.log("something");
+        }();
+    }
+}

test/compress/properties.js

@@ -17,9 +17,38 @@ dot_properties: {
     input: {
         a["foo"] = "bar";
         a["if"] = "if";
+        a["*"] = "asterisk";
+        a["\u0EB3"] = "unicode";
+        a[""] = "whitespace";
+        a["1_1"] = "foo";
     }
     expect: {
         a.foo = "bar";
         a["if"] = "if";
+        a["*"] = "asterisk";
+        a.\u0EB3 = "unicode";
+        a[""] = "whitespace";
+        a["1_1"] = "foo";
+    }
+}
+
+dot_properties_es5: {
+    options = {
+        properties: true,
+        screw_ie8: true
+    };
+    input: {
+        a["foo"] = "bar";
+        a["if"] = "if";
+        a["*"] = "asterisk";
+        a["\u0EB3"] = "unicode";
+        a[""] = "whitespace";
+    }
+    expect: {
+        a.foo = "bar";
+        a.if = "if";
+        a["*"] = "asterisk";
+        a.\u0EB3 = "unicode";
+        a[""] = "whitespace";
     }
 }

test/compress/sequences.js

@@ -101,10 +101,12 @@ lift_sequences_1: {
 lift_sequences_2: {
     options = { sequences: true, evaluate: true };
     input: {
-        q = 1 + (foo(), bar(), 5) + 7 * (5 / (3 - (a(), (QW=ER), c(), 2))) - (x(), y(), 5);
+        foo.x = (foo = {}, 10);
+        bar = (bar = {}, 10);
     }
     expect: {
-        foo(), bar(), a(), QW = ER, c(), x(), y(), q = 36
+        foo.x = (foo = {}, 10),
+        bar = {}, bar = 10;
     }
 }
 

test/compress/switch.js

@@ -0,0 +1,260 @@
+constant_switch_1: {
+    options = { dead_code: true, evaluate: true };
+    input: {
+        switch (1+1) {
+          case 1: foo(); break;
+          case 1+1: bar(); break;
+          case 1+1+1: baz(); break;
+        }
+    }
+    expect: {
+        bar();
+    }
+}
+
+constant_switch_2: {
+    options = { dead_code: true, evaluate: true };
+    input: {
+        switch (1) {
+          case 1: foo();
+          case 1+1: bar(); break;
+          case 1+1+1: baz();
+        }
+    }
+    expect: {
+        foo();
+        bar();
+    }
+}
+
+constant_switch_3: {
+    options = { dead_code: true, evaluate: true };
+    input: {
+        switch (10) {
+          case 1: foo();
+          case 1+1: bar(); break;
+          case 1+1+1: baz();
+          default:
+            def();
+        }
+    }
+    expect: {
+        def();
+    }
+}
+
+constant_switch_4: {
+    options = { dead_code: true, evaluate: true };
+    input: {
+        switch (2) {
+          case 1:
+            x();
+            if (foo) break;
+            y();
+            break;
+          case 1+1:
+            bar();
+          default:
+            def();
+        }
+    }
+    expect: {
+        bar();
+        def();
+    }
+}
+
+constant_switch_5: {
+    options = { dead_code: true, evaluate: true };
+    input: {
+        switch (1) {
+          case 1:
+            x();
+            if (foo) break;
+            y();
+            break;
+          case 1+1:
+            bar();
+          default:
+            def();
+        }
+    }
+    expect: {
+        // the break inside the if ruins our job
+        // we can still get rid of irrelevant cases.
+        switch (1) {
+          case 1:
+            x();
+            if (foo) break;
+            y();
+        }
+        // XXX: we could optimize this better by inventing an outer
+        // labeled block, but that's kinda tricky.
+    }
+}
+
+constant_switch_6: {
+    options = { dead_code: true, evaluate: true };
+    input: {
+        OUT: {
+            foo();
+            switch (1) {
+              case 1:
+                x();
+                if (foo) break OUT;
+                y();
+              case 1+1:
+                bar();
+                break;
+              default:
+                def();
+            }
+        }
+    }
+    expect: {
+        OUT: {
+            foo();
+            x();
+            if (foo) break OUT;
+            y();
+            bar();
+        }
+    }
+}
+
+constant_switch_7: {
+    options = { dead_code: true, evaluate: true };
+    input: {
+        OUT: {
+            foo();
+            switch (1) {
+              case 1:
+                x();
+                if (foo) break OUT;
+                for (var x = 0; x < 10; x++) {
+                    if (x > 5) break; // this break refers to the for, not to the switch; thus it
+                                      // shouldn't ruin our optimization
+                    console.log(x);
+                }
+                y();
+              case 1+1:
+                bar();
+                break;
+              default:
+                def();
+            }
+        }
+    }
+    expect: {
+        OUT: {
+            foo();
+            x();
+            if (foo) break OUT;
+            for (var x = 0; x < 10; x++) {
+                if (x > 5) break;
+                console.log(x);
+            }
+            y();
+            bar();
+        }
+    }
+}
+
+constant_switch_8: {
+    options = { dead_code: true, evaluate: true };
+    input: {
+        OUT: switch (1) {
+          case 1:
+            x();
+            for (;;) break OUT;
+            y();
+            break;
+          case 1+1:
+            bar();
+          default:
+            def();
+        }
+    }
+    expect: {
+        OUT: {
+            x();
+            for (;;) break OUT;
+            y();
+        }
+    }
+}
+
+constant_switch_9: {
+    options = { dead_code: true, evaluate: true };
+    input: {
+        OUT: switch (1) {
+          case 1:
+            x();
+            for (;;) if (foo) break OUT;
+            y();
+          case 1+1:
+            bar();
+          default:
+            def();
+        }
+    }
+    expect: {
+        OUT: {
+            x();
+            for (;;) if (foo) break OUT;
+            y();
+            bar();
+            def();
+        }
+    }
+}
+
+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';
+    }
+}

test/run-tests.js

@@ -7,8 +7,15 @@ var assert = require("assert");
 var sys = require("util");
 
 var tests_dir = path.dirname(module.filename);
+var failures = 0;
+var failed_files = {};
 
 run_compress_tests();
+if (failures) {
+    sys.error("\n!!! Failed " + failures + " test cases.");
+    sys.error("!!! " + Object.keys(failed_files).join(", "));
+    process.exit(1);
+}
 
 /* -----[ utils ]----- */
 
@@ -83,6 +90,8 @@ function run_compress_tests() {
                     output: output,
                     expected: expect
                 });
+                failures++;
+                failed_files[file] = 1;
             }
         }
         var tests = parse_test(path.resolve(dir, file));

tools/node.js

@@ -1,18 +1,5 @@
 var path = require("path");
 var fs = require("fs");
-
-// Avoid NodeJS warning.
-//
-// There's a --no-deprecation command line argument supported by
-// NodeJS, but that's tricky to use, so I'd like to set it from the
-// program itself.  Turns out you need to set `process.noDeprecation`,
-// but by the time you can set that the `path` module is already
-// loaded and `path.existsSync` is already changed to display that
-// warning, therefore here's the poor solution:
-if (fs.existsSync) {
-    path.existsSync = fs.existsSync;
-}
-
 var vm = require("vm");
 var sys = require("util");
 
@@ -69,10 +56,15 @@ exports.minify = function(files, options) {
         inSourceMap  : null,
         fromString   : false,
         warnings     : false,
+        mangle       : {},
+        output       : null,
+        compress     : {}
     });
     if (typeof files == "string")
         files = [ files ];
 
+    UglifyJS.base54.reset();
+
     // 1. parse
     var toplevel = null;
     files.forEach(function(file){
@@ -86,33 +78,42 @@ 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 + ""
     };
 };