v1.12.9

.hound.yml

@@ -0,0 +1,3 @@
+java_script:
+  enabled: true
+  config_file: .jshintrc

.npmignore

@@ -8,4 +8,4 @@ Makefile
 .*
 dist
 tests.json
-!README.md
+CHANGELOG.md

CHANGELOG.md

@@ -1,3 +1,35 @@
+# 1.12.9
+
+ * Escape unicode characters when generating string `Literal`s.
+ * Fix semicolons being output for statements in `ExportDeclaration`.
+ * Fix `WithStatement` missing parenthesis.
+
+# 1.12.8
+
+ * Temporarily forbid `AssignmentExpression` destructuring outside of `ExpressionStatement`.
+
+# 1.12.7
+
+ * Update to latest `acorn-6to5`.
+
+# 1.12.6
+
+ * Update to latest `acorn-6to5`.
+
+# 1.12.5
+
+ * Fix excessive whitespace trimming resulting in innaccurate sourcemap line.
+
+# 1.12.4
+
+ * Add `doc` folder for documentation.
+
+# 1.12.3
+
+ * Support generator comprehensions.
+ * Use `Array.from` instead of `Array.prototype.slice` in spread transformer.
+ * Support spread in `NewExpression`s.
+
 # 1.12.2
 
  * Upgrade `matcha` to `0.6.0` and `browserify` to `6.3.2`.

CONTRIBUTING.md

@@ -0,0 +1,31 @@
+# Contributing
+
+ * **General**
+   * No ES6 syntax features or methods, exclusively ES5.
+   * Max of five arguments for functions
+   * Max depth of four nested blocks
+   * 2-spaced soft tabs
+ * **Naming**
+   * CamelCase all class names
+   * camelBack all variable names
+ * **Spacing**
+   * 80 character line max
+   * Spaces after all keywords
+   * Spaces before all left curly braces
+ * **Comments**
+   * Use JSDoc-style comments for methods
+   * Single-line comments for ambiguous code
+ * **Quotes**
+   * Always use double quotes
+   * Only use single quotes when the string contains a double quote
+ * **Declaration**
+   * No unused variables
+   * No pollution of global variables and prototypes
+
+## Testing
+
+    $ make test
+
+## Linting
+
+    $ make lint

README.md

@@ -24,492 +24,6 @@
   </a>
 </p>
 
-**6to5** turns ES6 code into vanilla ES5, so you can use ES6 features **today.**
+**6to5** turns ES6+ code into vanilla ES5, so you can use next generation features **today.**
 
- - **Readable** - formatting is retained if possible so your generated code is as similar as possible.
- - **Extensible** - with a large range of [plugins](#plugins) and **browser support**.
- - **Lossless** - **source map support** so you can debug your compiled code with ease.
- - **Compact** - maps directly to the equivalent ES5 with **no runtime**[\*](#generators).
-
-## Installation
-
-It's as easy as:
-
-    $ npm install -g 6to5
-
-## Table of Contents
-
-- [Features](#features)
-- [Usage](#usage)
-  - [Plugins](#plugins)
-  - [CLI](#cli)
-  - [Node](#node-1)
-  - [Browser](#browser)
-- [Modules](#modules)
-- [Caveats](#caveats)
-- [Polyfill](#polyfill)
-- [Optional runtime](#optional-runtime)
-- [React/JSX](#reactjsx)
-- [Differences](#differences)
-
-## [Features](FEATURES.md)
-
- - [Array comprehension](FEATURES.md#array-comprehension)
- - [Async functions](FEATURES.md#async-functions) via [regenerator](https://github.com/facebook/regenerator)
- - [Arrow functions](FEATURES.md#arrow-functions)
- - [Classes](FEATURES.md#classes)
- - [Computed property names](FEATURES.md#computed-property-names)
- - [Constants](FEATURES.md#constants)
- - [Default parameters](FEATURES.md#default-parameters)
- - [Destructuring](FEATURES.md#destructuring)
- - [For-of](FEATURES.md#for-of)
- - [Generators](FEATURES.md#generators) via [regenerator](https://github.com/facebook/regenerator)
- - [Let scoping](FEATURES.md#let-scoping)
- - [Modules](FEATURES.md#modules)
- - [Numeric literals](FEATURES.md#numeric-literals)
- - [Property method assignment](FEATURES.md#property-method-assignment)
- - [Property name shorthand](FEATURES.md#property-name-shorthand)
- - [Rest parameters](FEATURES.md#rest-parameters)
- - [Spread](FEATURES.md#spread)
- - [Template literals](FEATURES.md#template-literals)
- - [Unicode regex](FEATURES.md#unicode-regex)
-
-## Usage
-
-### Plugins
-
- - [Broccoli](https://github.com/very-geek/broccoli-6to5-transpiler)
- - [Browserify](https://github.com/6to5/6to5-browserify)
- - [Brunch](https://github.com/es128/6to5-brunch)
- - [Duo](https://github.com/bdo-labs/duo6to5)
- - [Connect](https://github.com/6to5/6to5-connect)
- - [Gulp](https://github.com/sindresorhus/gulp-6to5)
- - [Grunt](https://github.com/sindresorhus/grunt-6to5)
- - [Jade](https://github.com/Apoxx/jade-6to5)
- - [Jest](https://github.com/6to5/6to5-jest)
- - [Karma](https://github.com/shuhei/karma-6to5-preprocessor)
- - [Mocha](https://github.com/6to5/6to5-mocha)
- - [Rails](https://github.com/6to5/6to5-rails)
- - [webpack](https://github.com/Couto/6to5-loader)
-
-### CLI
-
-Compile the file `script.js` and output it to stdout.
-
-    $ 6to5 script.js
-
-Compile the file `script.js` and output it to `script-compiled.js`.
-
-    $ 6to5 script.js --out-file script-compiled.js
-
-Compile the file `script.js` and output it to `script-compiled.js` and save a
-source map to `script-compiled.js.map`.
-
-    $ 6to5 script.js --source-maps --out-file script-compiled.js
-
-Compile the file `script.js` and output it to `script-compiled.js` with a source
-map embedded in a comment at the bottom.
-
-    $ 6to5 script.js --source-maps-inline --out-file script-compiled.js
-
-Compile the entire `src` directory and output it to the `lib` directory.
-
-    $ 6to5 src --out-dir lib
-
-Compile the entire `src` directory and output it to the one concatenated file.
-
-    $ 6to5 src --out-file script-compiled.js
-
-Pipe a file in via stdin and output it to `script-compiled.js`
-
-    $ 6to5 --out-file script-compiled.js < script.js
-
-#### Node
-
-Launch a repl.
-
-    $ 6to5-node
-
-Evaluate code.
-
-    $ 6to5-node -e "class Test { }"
-
-Compile and run `test.js`.
-
-    $ 6to5-node test
-
-### Node
-
-```javascript
-var to5 = require("6to5");
-
-var result = to5.transform("code();", options);
-result.code;
-result.map;
-result.ast;
-
-to5.transformFileSync("filename.js", options).code;
-
-to5.transformFile("filename.js", options, function (err, result) {
-
-});
-```
-
-##### Options
-
-```javascript
-{
-  // Filename for use in errors etc.
-  // Default: "unknown"
-  filename: "filename",
-
-  // List of transformers to EXCLUDE.
-  // Run `6to5 --help` to see a full list of transformers.
-  blacklist: [],
-
-  // List of transformers to ONLY use.
-  // Run `6to5 --help` to see a full list of transformers.
-  whitelist: [],
-
-  // Module formatter to use
-  // Run `6to5 --help` to see a full list of module formatters.
-  // Default: "common"
-  modules: "common",
-
-  // If truthy, adds a `map` property to returned output.
-  // If set to "inline", a comment with a sourceMappingURL directive is added to
-  // the bottom of the returned code.
-  // Default: false
-  sourceMap: true,
-
-  // Set `file` on returned source map.
-  // Default: `filename` option.
-  sourceMapName: "filename",
-
-  // Set `sources[0]` on returned source map.
-  // Default: `filename` option.
-  sourceFileName: "filename",
-
-  // Optionally replace all 6to5 helper declarations with a referenece to this
-  // variable. If set to `true` then the default namespace is used "to5Runtime".
-  // Default: false
-  runtime: true
-}
-```
-
-#### Require hook
-
-All subsequent files required by node with the extensions `.es6` and `.js` will
-be transformed by 6to5. The polyfill specified in [Polyfill](#polyfill) is also
-required.
-
-```javascript
-require("6to5/register");
-```
-
-**NOTE:** By default all requires to `node_modules` will be ignored. You can
-override this by passing an ignore regex via:
-
-```javascript
-require("6to5/register")({
-  // This will override `node_modules` ignoring - you can alternatively pass
-  // a regex
-  ignore: false
-});
-```
-
-##### Options
-
-```javascript
-require("6to5/register")({
-  // Optional ignore regex - if any filenames **do** match this regex then they
-  // aren't compiled
-  ignore: /regex/,
-
-  // Optional only regex - if any filenames **don't** match this regex then they
-  // aren't compiled
-  only: /my_es6_folder/,
-
-  // See options above for usage
-  whitelist: [],
-  blacklist: [],
-
-  // This will remove the currently hooked extensions of .es6 and .js so you'll
-  // have to add them back if you want them to be used again.
-  extensions: [".js", ".es6"]
-});
-```
-
-### Browser
-
-A browser version of 6to5 is available from `browser.js` inside the 6to5
-directory in an npm release.
-
-#### Scripts
-
-While it's not recommended for serious use, when the browser version is included
-all scripts with the type `text/ecmascript-6` and `text/6to5` are automatically
-compiled and ran.
-
-For example:
-
-```html
-<script src="node_modules/6to5/browser.js"></script>
-<script type="text/6to5">
-class Test {
-  test() {
-    return "test";
-  }
-}
-
-var test = new Test;
-test.test();
-</script>
-```
-
-#### Build
-
-You can build a browser version of the compiler by running the following in the
-6to5 directory:
-
-    $ make build
-
-This will output the files `dist/6to5.js` and `dist/6to5.min.js`.
-
-#### API
-
-```javascript
-to5.transform("class Test {}").code;
-```
-
-#### Test
-
-To test 6to5 in your browser run:
-
-    $ make test-browser
-
-And open `test/browser.html` in your browser if it doesn't open automatically.
-
-## [Modules](MODULES.md)
-
-See [Modules - Common](MODULES.md#common-default) for documentation on the
-default module formatting.
-
-Alternatively see [Modules](MODULES.md) for all other supported module formatting types.
-
-## Caveats
-
-### For-of
-
-A polyfill is required for for-of functionality that implements `Symbol` and
-adds `prototype[Symbol.iterator]` behaviour to built-ins. Using the polyfills
-specified in [polyfill](#polyfill) suffices.
-
-### Classes
-
-Built-in classes such as `Date`, `Array` and `DOM` cannot be subclassed due to
-limitations in ES5 implementations.
-
-If you're inheriting from a class then static properties are inherited from it
-via [\_\_proto\_\_](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/proto),
-this is widely supported but you may run into problems with much older browsers.
-
-**NOTE:** `__proto__` is not supported on IE <= 9 so static properties
-**will not** be inherited. A possible workaround is to use `super();`:
-
-```javascript
-class Foo {
-  static foo() {
-
-  }
-}
-
-class Bar extends Foo {
-  static foo() {
-    super();
-  }
-}
-```
-
-### Generators
-
-The [regenerator runtime](https://github.com/facebook/regenerator/blob/master/runtime.js)
-and an [ES6 polyfill](#polyfill) are required in order for generators to work.
-
-## Polyfill
-
-6to5 includes a polyfill that includes the
-[regenerator runtime](https://github.com/facebook/regenerator/blob/master/runtime.js) and the
-[es6-shim](https://github.com/paulmillr/es6-shim) and
-[es6-symbol](https://github.com/medikoo/es6-symbol) polyfills.
-
-### Node
-
-```javascript
-require("6to5/polyfill");
-```
-
-### Browser
-
-Available from the `browser-polyfill.js` file within the 6to5 directory of an
-npm release.
-
-## Optional runtime
-
-6to5 has a few helper functions that'll be placed at the top of the generated
-code if needed so it's not inlined multiple times throughout that file. This may
-become an issue if you have multiple files, especially when you're sending them
-to the browser. gzip alleviates most of this concern but it's still not ideal.
-
-You can tell 6to5 to not place any declarations at the top of your files and
-instead just point them to a reference contained within the runtime.
-
-Simply use the following option if you're using the [Node API](#node-1):
-
-```javascript
-{
-  runtime: true
-}
-```
-
-or the following flag if you're using the [CLI](#cli):
-
-    $ 6to5 --runtime
-
-Then just include the runtime before your generated code.
-
-### Getting the runtime
-
-You can get the runtime via either:
-
-    $ 6to5-runtime
-
-or
-
-```javascript
-require("6to5").runtime();
-```
-
-or from an npm release in `runtime.js` from the 6to5 directory.
-
-### Customising namespace
-
-You can also customise the runtime namespace by passing an optional namespace
-argument:
-
-```javascript
-require("6to5").runtime("myCustomNamespace");
-```
-
-    $ 6to5-runtime myCustomNamespace
-
-See [Options - runtime](#options) for documentation on changing the reference in
-generated code.
-
-## React/JSX
-
-6to5 has built-in support for React v0.12. Tags are automatically transformed to
-their equivalent `React.createElement(...)` and `displayName` is automatically
-inferred and added to all `React.createClass` calls.
-
-To disable this behaviour add `react` to your blacklist.
-
-## Differences
-
-### Philosophy
-
-The fundamental concept behind 6to5 is that the generated code must be close as
-possible to the original, retaining all the same formatting and readability.
-
-Many other transpilers are just concerned with making the code work while 6to5
-is concerned with making sure it works **and** is readable at the same time.
-
-For example, given the following array comprehension:
-
-```javascript
-var seattlers = [for (c of customers) if (c.city == "Seattle") { name: c.name, age: c.age }];
-```
-
-is generated to the following with 6to5:
-
-```javascript
-var seattlers = customers.filter(function (c) {
-  return c.city == "Seattle";
-}).map(function (c) {
-  return {
-    name: c.name,
-    age: c.age
-  };
-});
-```
-
-The following is what Traceur generates:
-
-```javascript
-var seattlers = (function() {
-  var c;
-  var $__20 = 0,
-      $__21 = [];
-  for (var $__22 = customers[$traceurRuntime.toProperty(Symbol.iterator)](),
-      $__23; !($__23 = $__22.next()).done; ) {
-    c = $__23.value;
-    if (c.city == "Seattle")
-      $traceurRuntime.setProperty($__21, $__20++, {
-        name: c.name,
-        age: c.age
-      });
-  }
-  return $__21;
-}());
-```
-
-As you can tell, it's not very pretty, unreadable even. Instead of mapping
-directly to a runtime, like other transpilers, 6to5 maps directly to the
-equivalent ES5.
-
-I'm not saying 6to5 is for everyone or even suited for everything. Traceur is
-better suited if you'd like a full ES6 environment with polyfills and all.
-
-### Comparison to other transpilers
-
-|                              | 6to5 | Traceur | esnext | es6now | es6-transpiler | jstransform |
-| ---------------------------- | ---- | ------- | ------ | ------ | -------------- | ----------- |
-| No runtime                   | ✓    |         |        |        | ✓              | ✓           |
-| Source maps                  | ✓    | ✓       | ✓      |        | ✓              | ✓           |
-| No compiler global pollution | ✓    |         | ✓      |        | ✓              | ✓           |
-| Arrow functions              | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
-| Classes                      | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
-| Computed property names      | ✓    | ✓       | ✓      | ✓      | ✓              |             |
-| Constants                    | ✓    | ✓       |        |        | ✓              |             |
-| Default parameters           | ✓    | ✓       | ✓      | ✓      | ✓              |             |
-| Destructuring                | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
-| For-of                       | ✓    | ✓       | ✓      | ✓      | ✓              |             |
-| Generators                   | ✓    | ✓       | ✓      |        |                |             |
-| Let scoping                  | ✓    | ✓       |        |        | ✓              |             |
-| Modules                      | ✓    | ✓       |        | ✓      |                |             |
-| Property method assignment   | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
-| Property name shorthand      | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
-| Rest parameters              | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
-| Spread                       | ✓    | ✓       | ✓      | ✓      | ✓              |             |
-| Template literals            | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
-| Unicode regex                | ✓    | ✓       |        |        | ✓              |             |
-
-#### [Traceur](https://github.com/google/traceur-compiler)
-
-Traceur requires quite a bulky runtime (~75KB) and produces quite verbose code.
-While this can be trimmed down by selectively building the runtime, it's an
-unneccesary step when a runtime can be eliminated entirely.
-
-#### [es6now](https://github.com/zenparsing/es6now)
-
-es6now doesn't output sourcemaps. This is cited as a positive as line-to-line
-mapping is the goal. This however obviously doesn't retain column mapping
-resulting in the output code not being very pleasant.
-
-#### [es6-transpiler](https://github.com/termi/es6-transpiler)
-
-The es6-transpiler compiler requires shims to operate which pollutes the global
-scope resulting in possible collisions.
-
-es6-transpiler maps line-by-line, just like es6now, this results in the same
-issues such as lack of column information and unpleasant code output.
+For more information view the [documentation](https://6to5.github.io).

bin/_6to5-node

@@ -1,10 +1,10 @@
 #!/usr/bin/env node
 
 var commander = require("commander");
-var util      = require("../lib/6to5/util");
 var path      = require("path");
 var repl      = require("repl");
 var to5       = require("../lib/6to5");
+var util      = require("../lib/6to5/util");
 var vm        = require("vm");
 var _         = require("lodash");
 

doc/browser.md

@@ -0,0 +1,61 @@
+# Browser
+
+A browser version of 6to5 is available from `browser.js` inside the 6to5
+directory in an npm release.
+
+## Scripts
+
+While it's not recommended for serious use, when the browser version is included
+all scripts with the type `text/ecmascript-6` and `text/6to5` are automatically
+compiled and ran.
+
+For example:
+
+```html
+<script src="node_modules/6to5/browser.js"></script>
+<script type="text/6to5">
+class Test {
+  test() {
+    return "test";
+  }
+}
+
+var test = new Test;
+test.test();
+</script>
+```
+
+## Build
+
+You can build a browser version of the compiler by running the following in the
+6to5 directory:
+
+    $ make build
+
+This will output the files `dist/6to5.js` and `dist/6to5.min.js`.
+
+## Test
+
+To test 6to5 in your browser run:
+
+    $ make test-browser
+
+And open `test/browser.html` in your browser if it doesn't open automatically.
+
+## API
+
+### to5.transform(code, [opts])
+
+See [options](usage.md#options) for additional documentation.
+
+```javascript
+to5.transform("class Test {}").code;
+```
+
+### to5.run(code, [opts])
+
+See [options](usage.md#options) for additional documentation.
+
+```javascript
+to5.run("class Test {}");
+```

doc/caveats.md

@@ -0,0 +1,43 @@
+# Caveats
+
+## Async/Generators
+
+The [regenerator runtime](https://github.com/facebook/regenerator/blob/master/runtime.js)
+and an [ES6 polyfill](polyfill.md) are required in order for generators to work.
+
+## Classes
+
+Built-in classes such as `Date`, `Array` and `DOM` cannot be subclassed due to
+limitations in ES5 implementations.
+
+If you're inheriting from a class then static properties are inherited from it
+via [\_\_proto\_\_](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/proto),
+this is widely supported but you may run into problems with much older browsers.
+
+**NOTE:** `__proto__` is not supported on IE <= 9 so static properties
+**will not** be inherited. A possible workaround is to use `super();`:
+
+```javascript
+class Foo {
+  static foo() {
+
+  }
+}
+
+class Bar extends Foo {
+  static foo() {
+    super();
+  }
+}
+```
+
+## For-of
+
+A polyfill is required for for-of functionality that implements `Symbol` and
+adds `prototype[Symbol.iterator]` behaviour to built-ins. Using the polyfills
+specified in [polyfill](polyfill.md) suffices.
+
+## Spread
+
+An [ES6 polyfill](polyfill.md) is required in order for spread to work. More
+specifically a polyfill for `Array.from`.

doc/differences.md

@@ -0,0 +1,103 @@
+# Differences
+
+## Philosophy
+
+The fundamental concept behind 6to5 is that the generated code must be close as
+possible to the original, retaining all the same formatting and readability.
+
+Many other transpilers are just concerned with making the code work while 6to5
+is concerned with making sure it works **and** is readable at the same time.
+
+For example, given the following array comprehension:
+
+```javascript
+var seattlers = [for (c of customers) if (c.city == "Seattle") { name: c.name, age: c.age }];
+```
+
+is generated to the following with 6to5:
+
+```javascript
+var seattlers = customers.filter(function (c) {
+  return c.city == "Seattle";
+}).map(function (c) {
+  return {
+    name: c.name,
+    age: c.age
+  };
+});
+```
+
+The following is what Traceur generates:
+
+```javascript
+var seattlers = (function() {
+  var c;
+  var $__20 = 0,
+      $__21 = [];
+  for (var $__22 = customers[$traceurRuntime.toProperty(Symbol.iterator)](),
+      $__23; !($__23 = $__22.next()).done; ) {
+    c = $__23.value;
+    if (c.city == "Seattle")
+      $traceurRuntime.setProperty($__21, $__20++, {
+        name: c.name,
+        age: c.age
+      });
+  }
+  return $__21;
+}());
+```
+
+As you can tell, it's not very pretty, unreadable even. Instead of mapping
+directly to a runtime, like other transpilers, 6to5 maps directly to the
+equivalent ES5.
+
+I'm not saying 6to5 is for everyone or even suited for everything. Traceur is
+better suited if you'd like a full ES6 environment with polyfills and all.
+
+## Comparison to other transpilers
+
+|                              | 6to5 | Traceur | esnext | es6now | es6-transpiler | jstransform |
+| ---------------------------- | ---- | ------- | ------ | ------ | -------------- | ----------- |
+| No runtime                   | ✓    |         |        |        | ✓              | ✓           |
+| Source maps                  | ✓    | ✓       | ✓      |        | ✓              | ✓           |
+| No compiler global pollution | ✓    |         | ✓      |        | ✓              | ✓           |
+| Browser support              | ✓    | ✓       | ✓      |        |                |             |
+| Array comprehension          | ✓    | ✓       |        |        | ✓              |             |
+| Arrow functions              | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
+| Async functions              | ✓    | ✓       | ✓      |        |                |             |
+| Classes                      | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
+| Computed property names      | ✓    | ✓       | ✓      | ✓      | ✓              |             |
+| Constants                    | ✓    | ✓       |        |        | ✓              |             |
+| Default parameters           | ✓    | ✓       | ✓      | ✓      | ✓              |             |
+| Destructuring                | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
+| For-of                       | ✓    | ✓       | ✓      | ✓      | ✓              |             |
+| Generators                   | ✓    | ✓       | ✓      |        |                |             |
+| Generator comprehension      | ✓    | ✓       |        |        |                |             |
+| Let scoping                  | ✓    | ✓       |        |        | ✓              |             |
+| Modules                      | ✓    | ✓       |        | ✓      |                |             |
+| Property method assignment   | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
+| Property name shorthand      | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
+| Rest parameters              | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
+| Spread                       | ✓    | ✓       | ✓      | ✓      | ✓              |             |
+| Template literals            | ✓    | ✓       | ✓      | ✓      | ✓              | ✓           |
+| Unicode regex                | ✓    | ✓       |        |        | ✓              |             |
+
+### [Traceur](https://github.com/google/traceur-compiler)
+
+Traceur requires quite a bulky runtime (~75KB) and produces quite verbose code.
+While this can be trimmed down by selectively building the runtime, it's an
+unneccesary step when a runtime can be eliminated entirely.
+
+### [es6now](https://github.com/zenparsing/es6now)
+
+es6now doesn't output sourcemaps. This is cited as a positive as line-to-line
+mapping is the goal. This however obviously doesn't retain column mapping
+resulting in the output code not being very pleasant.
+
+### [es6-transpiler](https://github.com/termi/es6-transpiler)
+
+The es6-transpiler compiler requires shims to operate which pollutes the global
+scope resulting in possible collisions.
+
+es6-transpiler maps line-by-line, just like es6now, this results in the same
+issues such as lack of column information and unpleasant code output.

doc/features.md

@@ -3,7 +3,32 @@
 ## Array comprehension
 
 ```javascript
-[for (i of [1, 2, 3]) i * i]; // [1, 4, 9]
+var results = [for (c of customers) if (c.city == "Seattle") { name: c.name, age: c.age }]
+```
+
+## Arrow functions
+
+```javascript
+// Expression bodies
+var odds = evens.map(v => v + 1);
+var nums = evens.map((v, i) => v + i);
+
+// Statement bodies
+nums.forEach(v => {
+  if (v % 5 === 0)
+    fives.push(v);
+});
+
+// Lexical this
+var bob = {
+  _name: "Bob",
+  _friends: [],
+  printFriends() {
+    this._friends.forEach(f => {
+      console.log(this._name + " knows " + f);
+    });
+  }
+};
 ```
 
 ## Async functions
@@ -16,31 +41,27 @@ async function chainAnimationsAsync(elem, animations) {
 }
 ```
 
-## Arrow functions
-
-```javascript
-arr.map(x => x * x);
-```
-
-## Let scoping
-
-```javascript
-for (let i in arr) {
-  let v = arr[i];
-}
-```
-
 ## Classes
 
 ```javascript
-class Foo extends Bar {
-  constructor() { }
+class SkinnedMesh extends THREE.Mesh {
+  constructor(geometry, materials) {
+    super(geometry, materials);
 
-  foo() { }
+    this.idMatrix = SkinnedMesh.defaultMatrix();
+    this.bones = [];
+    this.boneMatrices = [];
+    //...
+  }
 
-  get bar() { }
+  update(camera) {
+    //...
+    super.update();
+  }
 
-  set bar() { }
+  static defaultMatrix() {
+    return new THREE.Matrix4();
+  }
 }
 ```
 
@@ -70,16 +91,35 @@ var MULTIPLIER; // error
 ## Default parameters
 
 ```javascript
-function foo(bar = "foo") {
-  return bar + "bar";
+function f(x, y = 12) {
+  // y is 12 if not passed (or passed as undefined)
+  return x + y;
 }
+f(3) == 15
 ```
 
 ## Destructuring
 
 ```javascript
-var [a, [b], c, d] = ["hello", [", ", "junk"], ["world"]];
-console.log(a + b + c); // hello, world
+// list matching
+var [a, , b] = [1,2,3];
+
+// object matching
+var { op: a, lhs: { op: b }, rhs: c } = getASTNode();
+
+// object matching shorthand
+// binds `op`, `lhs` and `rhs` in scope
+var { op, lhs, rhs } = getASTNode();
+
+// Can be used in parameter position
+function g({ name: x }) {
+  console.log(x);
+}
+g({ name: 5 });
+
+// Fail-soft destructuring
+var [a] = [];
+a === undefined;
 ```
 
 ## For-of
@@ -95,6 +135,19 @@ for (var i of [1, 2, 3]) {
 ```javascript
 ```
 
+## Generator comprehension
+
+```javascript
+```
+
+## Let scoping
+
+```javascript
+for (let i in arr) {
+  let v = arr[i];
+}
+```
+
 ## Modules
 
 ```javascript
@@ -136,23 +189,21 @@ function f(x, y) {
 ## Rest parameters
 
 ```javascript
-function printList(name, ...items) {
-  console.log("list %s has the following items", name);
-  items.forEach(function (item) {
-    console.log(item);
-  });
+function f(x, ...y) {
+  // y is an Array
+  return x * y.length;
 }
+f(3, "hello", true) == 6
 ```
 
 ## Spread
 
 ```javascript
-function add(x, y) {
-  return x + y;
+function f(x, y, z) {
+  return x + y + z;
 }
-
-var numbers = [5, 10];
-add(...numbers); // 15
+// Pass each elem of array as argument
+f(...[1,2,3]) == 6
 ```
 
 ## Template literals

doc/index.md

@@ -0,0 +1,54 @@
+**6to5** turns ES6+ code into vanilla ES5, so you can use next generation features **today.**
+
+ - **Readable** - formatting is retained if possible so your generated code is as similar as possible.
+ - **Extensible** - with a large range of [plugins](plugins.md) and **browser support**.
+ - **Lossless** - **source map support** so you can debug your compiled code with ease.
+ - **Compact** - maps directly to the equivalent ES5 with **no runtime**[\*](caveats.md#generators).
+
+## Installation
+
+It's as easy as:
+
+    $ npm install -g 6to5
+
+## Usage
+
+Once you've installed 6to5, there are multiple paths you can take depending on
+how you want to use it.
+
+6to5 will simply compile your ES6+ script to ES5 if you pass it as an argument
+to the command-line tool `6to5`:
+
+    $ 6to5 script.js
+
+If you have a file written using ES6+ and you just want to run it, `6to5-node`
+has you covered:
+
+    $ 6to5-node script.js
+
+And it doesn't end here! To see all the ways you can use 6to5, check out the
+[Usage](http://6to5.github.io/usage.html) page.
+
+## [Features](features.md)
+
+ - [Array comprehension](features.md#array-comprehension)
+ - [Async functions](features.md#async-functions) via [regenerator](https://github.com/facebook/regenerator)
+ - [Arrow functions](features.md#arrow-functions)
+ - [Classes](features.md#classes)
+ - [Computed property names](features.md#computed-property-names)
+ - [Constants](features.md#constants)
+ - [Default parameters](features.md#default-parameters)
+ - [Destructuring](features.md#destructuring)
+ - [For-of](features.md#for-of)
+ - [Generators](features.md#generators) via [regenerator](https://github.com/facebook/regenerator)
+ - [Generator comprehension](features.md#generator-comprehension)
+ - [Let scoping](features.md#let-scoping)
+ - [Modules](features.md#modules)
+ - [Numeric literals](features.md#numeric-literals)
+ - [Property method assignment](features.md#property-method-assignment)
+ - [Property name shorthand](features.md#property-name-shorthand)
+ - [React/JSX](react.md)
+ - [Rest parameters](features.md#rest-parameters)
+ - [Spread](features.md#spread)
+ - [Template literals](features.md#template-literals)
+ - [Unicode regex](features.md#unicode-regex)

doc/optional-runtime.md

@@ -0,0 +1,51 @@
+# Optional runtime
+
+6to5 has a few helper functions that'll be placed at the top of the generated
+code if needed so it's not inlined multiple times throughout that file. This may
+become an issue if you have multiple files, especially when you're sending them
+to the browser. gzip alleviates most of this concern but it's still not ideal.
+
+You can tell 6to5 to not place any declarations at the top of your files and
+instead just point them to a reference contained within the runtime.
+
+Simply use the following option if you're using the [Node API](usage.md#node):
+
+```javascript
+{
+  runtime: true
+}
+```
+
+or the following flag if you're using the [CLI](usage.md#cli):
+
+    $ 6to5 --runtime
+
+Then just include the runtime before your generated code.
+
+## Getting the runtime
+
+You can get the runtime via either:
+
+    $ 6to5-runtime
+
+or
+
+```javascript
+require("6to5").runtime();
+```
+
+or from an npm release in `runtime.js` from the 6to5 directory.
+
+## Customising namespace
+
+You can also customise the runtime namespace by passing an optional namespace
+argument:
+
+```javascript
+require("6to5").runtime("myCustomNamespace");
+```
+
+    $ 6to5-runtime myCustomNamespace
+
+See [Options - runtime](usage.md#options) for documentation on changing the
+reference in generated code.

doc/plugins.md

@@ -0,0 +1,15 @@
+# Plugins
+
+ - [Broccoli](https://github.com/very-geek/broccoli-6to5-transpiler)
+ - [Browserify](https://github.com/6to5/6to5-browserify)
+ - [Brunch](https://github.com/es128/6to5-brunch)
+ - [Duo](https://github.com/bdo-labs/duo6to5)
+ - [Connect](https://github.com/6to5/6to5-connect)
+ - [Gulp](https://github.com/sindresorhus/gulp-6to5)
+ - [Grunt](https://github.com/sindresorhus/grunt-6to5)
+ - [Jade](https://github.com/Apoxx/jade-6to5)
+ - [Jest](https://github.com/6to5/6to5-jest)
+ - [Karma](https://github.com/shuhei/karma-6to5-preprocessor)
+ - [Mocha](https://github.com/6to5/6to5-mocha)
+ - [Rails](https://github.com/6to5/6to5-rails)
+ - [webpack](https://github.com/Couto/6to5-loader)

doc/polyfill.md

@@ -0,0 +1,17 @@
+# Polyfill
+
+6to5 includes a polyfill that includes the
+[regenerator runtime](https://github.com/facebook/regenerator/blob/master/runtime.js) and the
+[es6-shim](https://github.com/paulmillr/es6-shim) and
+[es6-symbol](https://github.com/medikoo/es6-symbol) polyfills.
+
+## Node
+
+```javascript
+require("6to5/polyfill");
+```
+
+## Browser
+
+Available from the `browser-polyfill.js` file within the 6to5 directory of an
+npm release.

doc/react.md

@@ -0,0 +1,16 @@
+# React/JSX
+
+6to5 has built-in support for React v0.12. Tags are automatically transformed to
+their equivalent `React.createElement(...)` and `displayName` is automatically
+inferred and added to all `React.createClass` calls.
+
+## Blacklist
+
+To disable this behaviour add `react` to your blacklist:
+
+```javascript
+to5.transform("code", { blacklist: ["react"] });
+```
+
+
+    $ 6to5 --blacklist react

doc/usage.md

@@ -0,0 +1,161 @@
+# Usage
+
+## CLI
+
+Compile the file `script.js` and output it to stdout.
+
+    $ 6to5 script.js
+
+Compile the file `script.js` and output it to `script-compiled.js`.
+
+    $ 6to5 script.js --out-file script-compiled.js
+
+Compile the file `script.js` and output it to `script-compiled.js` and save a
+source map to `script-compiled.js.map`.
+
+    $ 6to5 script.js --source-maps --out-file script-compiled.js
+
+Compile the file `script.js` and output it to `script-compiled.js` with a source
+map embedded in a comment at the bottom.
+
+    $ 6to5 script.js --source-maps-inline --out-file script-compiled.js
+
+Compile the entire `src` directory and output it to the `lib` directory.
+
+    $ 6to5 src --out-dir lib
+
+Compile the entire `src` directory and output it to the one concatenated file.
+
+    $ 6to5 src --out-file script-compiled.js
+
+Pipe a file in via stdin and output it to `script-compiled.js`
+
+    $ 6to5 --out-file script-compiled.js < script.js
+
+### Node
+
+Launch a repl.
+
+    $ 6to5-node
+
+Evaluate code.
+
+    $ 6to5-node -e "class Test { }"
+
+Compile and run `test.js`.
+
+    $ 6to5-node test
+
+## Node
+
+```javascript
+var to5 = require("6to5");
+```
+
+### to5.transform(code, [opts]);
+
+```javascript
+var result = to5.transform("code();", options);
+result.code;
+result.map;
+result.ast;
+```
+
+### to5.transformFileSync(filename, [opts])
+
+```javascript
+to5.transformFileSync("filename.js", options).code;
+```
+
+### to5.transformFile(filename, [opts], callback)
+
+```javascript
+to5.transformFile("filename.js", options, function (err, result) {
+  result.code;
+});
+```
+
+#### Options
+
+```javascript
+{
+  // Filename for use in errors etc.
+  // Default: "unknown"
+  filename: "filename",
+
+  // List of transformers to EXCLUDE.
+  // Run `6to5 --help` to see a full list of transformers.
+  blacklist: [],
+
+  // List of transformers to ONLY use.
+  // Run `6to5 --help` to see a full list of transformers.
+  whitelist: [],
+
+  // Module formatter to use
+  // Run `6to5 --help` to see a full list of module formatters.
+  // Default: "common"
+  modules: "common",
+
+  // If truthy, adds a `map` property to returned output.
+  // If set to "inline", a comment with a sourceMappingURL directive is added to
+  // the bottom of the returned code.
+  // Default: false
+  sourceMap: true,
+
+  // Set `file` on returned source map.
+  // Default: `filename` option.
+  sourceMapName: "filename",
+
+  // Set `sources[0]` on returned source map.
+  // Default: `filename` option.
+  sourceFileName: "filename",
+
+  // Optionally replace all 6to5 helper declarations with a referenece to this
+  // variable. If set to `true` then the default namespace is used "to5Runtime".
+  // Default: false
+  runtime: true
+}
+```
+
+### Require hook
+
+All subsequent files required by node with the extensions `.es6` and `.js` will
+be transformed by 6to5. The polyfill specified in [Polyfill](polyfill.md) is
+also required.
+
+```javascript
+require("6to5/register");
+```
+
+**NOTE:** By default all requires to `node_modules` will be ignored. You can
+override this by passing an ignore regex via:
+
+```javascript
+require("6to5/register")({
+  // This will override `node_modules` ignoring - you can alternatively pass
+  // a regex
+  ignore: false
+});
+```
+
+#### Options
+
+```javascript
+require("6to5/register")({
+  // Optional ignore regex - if any filenames **do** match this regex then they
+  // aren't compiled
+  ignore: /regex/,
+
+  // Optional only regex - if any filenames **don't** match this regex then they
+  // aren't compiled
+  only: /my_es6_folder/,
+
+  // See options above for usage
+  whitelist: [],
+  blacklist: [],
+
+  // This will remove the currently hooked extensions of .es6 and .js so you'll
+  // have to add them back if you want them to be used again.
+  extensions: [".js", ".es6"]
+});
+```

lib/6to5/browser.js

@@ -2,13 +2,6 @@ var transform = module.exports = require("./transformation/transform");
 
 transform.transform = transform;
 
-transform.eval = function (code, opts) {
-  opts = opts || {};
-  opts.filename = opts.filename || "eval";
-  opts.sourceMap = "inline";
-  return eval(transform(code, opts).code);
-};
-
 transform.run = function (code, opts) {
   opts = opts || {};
   opts.sourceMap = "inline";

lib/6to5/file.js

@@ -18,7 +18,7 @@ function File(opts) {
   this.ast          = {};
 }
 
-File.declarations = ["extends", "class-props", "slice"];
+File.declarations = ["extends", "class-props", "slice", "apply-constructor"];
 
 File.normaliseOptions = function (opts) {
   opts = _.cloneDeep(opts || {});
@@ -30,7 +30,8 @@ File.normaliseOptions = function (opts) {
     sourceMap:  false,
     filename:   "unknown",
     modules:    "common",
-    runtime:    false
+    runtime:    false,
+    code:       true
   });
 
   // normalise windows path separators to unix
@@ -142,6 +143,14 @@ File.prototype.generate = function () {
   var opts = this.opts;
   var ast  = this.ast;
 
+  if (!opts.code) {
+    return {
+      code: "",
+      map:  null,
+      ast:  ast
+    };
+  }
+
   var result = generate(ast, opts, this.code);
 
   if (this.shebang) {
@@ -153,6 +162,8 @@ File.prototype.generate = function () {
     result.code += "\n" + util.sourceMapToComment(result.map);
   }
 
+  result.ast = result;
+
   return result;
 };
 

lib/6to5/generation/buffer.js

@@ -76,6 +76,8 @@ Buffer.prototype.newline = function (i, removeLast) {
   }
 
   if (_.isNumber(i)) {
+    if (this.endsWith(util.repeat(i, "\n"))) return;
+
     var self = this;
     _.times(i, function () {
       self.newline(null, removeLast);
@@ -86,7 +88,7 @@ Buffer.prototype.newline = function (i, removeLast) {
   if (removeLast && this.isLast("\n")) this.removeLast("\n");
 
   this.removeLast(" ");
-  this.buf = this.buf.replace(/\n(\s+)$/, "\n");
+  this.buf = this.buf.replace(/\n +$/, "\n");
   this._push("\n");
 };
 

lib/6to5/generation/generator.js

@@ -53,16 +53,16 @@ CodeGenerator.normaliseOptions = function (opts) {
 };
 
 CodeGenerator.generators = {
-  arrayComprehensions: require("./generators/array-comprehensions"),
-  templateLiterals:    require("./generators/template-literals"),
-  expressions:         require("./generators/expressions"),
-  statements:          require("./generators/statements"),
-  classes:             require("./generators/classes"),
-  methods:             require("./generators/methods"),
-  modules:             require("./generators/modules"),
-  types:               require("./generators/types"),
-  base:                require("./generators/base"),
-  jsx:                 require("./generators/jsx")
+  templateLiterals: require("./generators/template-literals"),
+  comprehensions:   require("./generators/comprehensions"),
+  expressions:      require("./generators/expressions"),
+  statements:       require("./generators/statements"),
+  classes:          require("./generators/classes"),
+  methods:          require("./generators/methods"),
+  modules:          require("./generators/modules"),
+  types:            require("./generators/types"),
+  base:             require("./generators/base"),
+  jsx:              require("./generators/jsx")
 };
 
 _.each(CodeGenerator.generators, function (generator) {
@@ -76,7 +76,6 @@ CodeGenerator.prototype.generate = function () {
 
   return {
     map:  this.map.get(),
-    ast:  ast,
     code: this.buffer.get()
   };
 };
@@ -116,8 +115,6 @@ CodeGenerator.prototype.print = function (node, parent, opts) {
   opts = opts || {};
 
   var newline = function (leading) {
-    var ignoreDuplicates = false;
-
     if (!opts.statement && !n.isUserWhitespacable(node, parent)) {
       return;
     }
@@ -140,7 +137,7 @@ CodeGenerator.prototype.print = function (node, parent, opts) {
       lines += needs(node, parent);
     }
 
-    self.newline(lines, ignoreDuplicates);
+    self.newline(lines);
   };
 
   if (this[node.type]) {

lib/6to5/generation/generators/classes.js

@@ -30,3 +30,11 @@ exports.ClassBody = function (node, print) {
     this.rightBrace();
   }
 };
+
+exports.MethodDefinition = function (node, print) {
+  if (node.static) {
+    this.push("static ");
+  }
+
+  this._method(node, print);
+};

lib/6to5/generation/generators/comprehensions.js

@@ -8,7 +8,8 @@ exports.ComprehensionBlock = function (node, print) {
 };
 
 exports.ComprehensionExpression = function (node, print) {
-  this.push("[");
+  this.push(node.generator ? "(" : "[");
+
   print.join(node.blocks, { separator: " " });
   this.space();
 
@@ -21,5 +22,6 @@ exports.ComprehensionExpression = function (node, print) {
   }
 
   print(node.body);
-  this.push("]");
+
+  this.push(node.generator ? ")" : "]");
 };

lib/6to5/generation/generators/jsx.js

@@ -74,5 +74,5 @@ exports.XJSClosingElement = function (node, print) {
 };
 
 exports.XJSEmptyExpression = function () {
-  this.push("null");
+
 };

lib/6to5/generation/generators/methods.js

@@ -41,6 +41,8 @@ exports._method = function (node, print) {
     this.push(kind + " ");
   }
 
+  if (value.async) this.push("async ");
+
   if (node.computed) {
     this.push("[");
     print(key);
@@ -54,16 +56,9 @@ exports._method = function (node, print) {
   print(value.body);
 };
 
-exports.MethodDefinition = function (node, print) {
-  if (node.static) {
-    this.push("static ");
-  }
-
-  this._method(node, print);
-};
-
 exports.FunctionDeclaration =
 exports.FunctionExpression = function (node, print) {
+  if (node.async) this.push("async ");
   this.push("function");
   if (node.generator) this.push("*");
   this.space();
@@ -74,6 +69,8 @@ exports.FunctionExpression = function (node, print) {
 };
 
 exports.ArrowFunctionExpression = function (node, print) {
+  if (node.async) this.push("async ");
+
   if (node.params.length === 1 && !node.defaults.length && !node.rest && t.isIdentifier(node.params[0])) {
     print(node.params[0]);
   } else {

lib/6to5/generation/generators/modules.js

@@ -25,9 +25,10 @@ exports.ExportDeclaration = function (node, print) {
 
   if (node.declaration) {
     print(node.declaration);
+    if (t.isStatement(node.declaration)) return;
   } else {
     if (specifiers.length === 1 && t.isExportBatchSpecifier(specifiers[0])) {
-      this.push("*");
+      print(specifiers[0]);
     } else {
       this.push("{");
       if (specifiers.length) {

lib/6to5/generation/generators/statements.js

@@ -4,6 +4,7 @@ exports.WithStatement = function (node, print) {
   this.keyword("with");
   this.push("(");
   print(node.object);
+  this.push(")");
   print.block(node.body);
 };
 
@@ -134,15 +135,6 @@ exports.SwitchStatement = function (node, print) {
   this.push(") {");
   print.sequence(node.cases, { indent: true });
   this.push("}");
-
-  //if (node.cases.length) {
-  //  this.newline();
-  //  print.sequence(node.cases, { indent: true });
-  //  this.newline();
-  //  this.rightBrace();
-  //} else {
-  //  this.push("}");
-  //}
 };
 
 exports.SwitchCase = function (node, print) {
@@ -154,13 +146,8 @@ exports.SwitchCase = function (node, print) {
     this.push("default:");
   }
 
-  if (node.consequent.length === 1) {
-    this.space();
-    print(node.consequent[0]);
-  } else if (node.consequent.length > 1) {
-    this.newline();
-    print.sequence(node.consequent, { indent: true });
-  }
+  this.space();
+  print.sequence(node.consequent, { indent: true });
 };
 
 exports.DebuggerStatement = function () {

lib/6to5/generation/generators/types.js

@@ -74,13 +74,20 @@ exports.Literal = function (node) {
   var val  = node.value;
   var type = typeof val;
 
-  if (type === "boolean" || type === "number" || type === "string") {
+  if (type === "string") {
+    val = JSON.stringify(val);
+
+    // escape unicode characters
+    val = val.replace(/[\u007f-\uffff]/g, function(c) {
+      return "\\u" + ("0000" + c.charCodeAt(0).toString(16)).slice(-4);
+    });
+
+    this.push(val);
+  } else if (type === "boolean" || type === "number") {
     this.push(JSON.stringify(val));
   } else if (node.regex) {
     this.push("/" + node.regex.pattern + "/" + node.regex.flags);
   } else if (val === null) {
     this.push("null");
-  } else if (node.raw) {
-    this.push(node.raw);
   }
 };

lib/6to5/generation/node/index.js

@@ -24,17 +24,14 @@ function Node(node, parent) {
 }
 
 Node.prototype.isUserWhitespacable = function () {
-  //var parent = this.parent;
+  var parent = this.parent;
   var node = this.node;
 
-  if (t.isUserWhitespacable(node)) {
+  if (t.isUserWhitespacable(node) ||
+      t.isSequenceExpression(parent)) {
     return true;
   }
 
-  //if (t.isArrayExpression(parent)) {
-  //  return true;
-  //}
-
   return false;
 };
 

lib/6to5/register.js

@@ -36,6 +36,7 @@ var blacklistTest = function (transformer, code) {
 };
 
 blacklistTest("arrayComprehension", "var foo = [for (foo of bar) foo * foo];");
+//blacklistTest("generatorComprehension", "");
 blacklistTest("arrowFunctions", "var foo = x => x * x;");
 blacklistTest("classes", "class Foo {}");
 blacklistTest("computedPropertyNames", "var foo = { [foo]: bar };");

lib/6to5/templates/apply-constructor.js

@@ -0,0 +1,5 @@
+(function (Constructor, args) {
+  var bindArgs = [null].concat(args);
+  var Factory = Constructor.bind.apply(Constructor, bindArgs);
+  return new Factory;
+});

lib/6to5/transformation/transform.js

@@ -31,6 +31,7 @@ _.each({
   propertyNameShorthand:    require("./transformers/property-name-shorthand"),
   constants:                require("./transformers/constants"),
   arrayComprehension:       require("./transformers/array-comprehension"),
+  generatorComprehension:   require("./transformers/generator-comprehension"),
   arrowFunctions:           require("./transformers/arrow-functions"),
   classes:                  require("./transformers/classes"),
 

lib/6to5/transformation/transformer.js

@@ -15,6 +15,7 @@ Transformer.normalise = function (transformer) {
   }
 
   _.each(transformer, function (fns, type) {
+    if (type[0] === "_") return;
     if (_.isFunction(fns)) fns = { enter: fns };
     transformer[type] = fns;
   });

lib/6to5/transformation/transformers/array-comprehension.js

@@ -37,39 +37,42 @@ var multiple = function (node, file) {
 
   var returnStatement = body.pop();
 
-  var build = function () {
-    var self = node.blocks.shift();
-    if (!self) return;
-
-    var child = build();
-    if (!child) {
-      // last item
-
-      child = util.template("array-push", {
-        STATEMENT: node.body,
-        KEY:       uid
-      }, true);
-
-      // add a filter as this is our final stop
-      if (node.filter) {
-        child = t.ifStatement(node.filter, t.blockStatement([child]));
-      }
-    }
-
-    return t.forOfStatement(
-      t.variableDeclaration("var", [t.variableDeclarator(self.left)]),
-      self.right,
-      t.blockStatement([child])
-    );
-  };
-
-  body.push(build());
+  body.push(exports._build(node, function () {
+    return util.template("array-push", {
+      STATEMENT: node.body,
+      KEY:       uid
+    }, true);
+  }));
   body.push(returnStatement);
 
   return container;
 };
 
+exports._build = function (node, buildBody) {
+  var self = node.blocks.shift();
+  if (!self) return;
+
+  var child = exports._build(node, buildBody);
+  if (!child) {
+    // last item
+    child = buildBody();
+
+    // add a filter as this is our final stop
+    if (node.filter) {
+      child = t.ifStatement(node.filter, t.blockStatement([child]));
+    }
+  }
+
+  return t.forOfStatement(
+    t.variableDeclaration("var", [t.variableDeclarator(self.left)]),
+    self.right,
+    t.blockStatement([child])
+  );
+};
+
 exports.ComprehensionExpression = function (node, parent, file) {
+  if (node.generator) return;
+
   if (node.blocks.length === 1 && t.isArrayExpression(node.blocks[0].right)) {
     return singleArrayExpression(node);
   } else {

lib/6to5/transformation/transformers/default-parameters.js

@@ -3,7 +3,7 @@ var t    = require("../../types");
 var _    = require("lodash");
 
 exports.Function = function (node) {
-  if (!node.defaults.length) return;
+  if (!node.defaults || !node.defaults.length) return;
   t.ensureBlock(node);
 
   _.each(node.defaults, function (def, i) {

lib/6to5/transformation/transformers/destructuring.js

@@ -146,6 +146,12 @@ exports.ExpressionStatement = function (node, parent, file, scope) {
   return nodes;
 };
 
+exports.AssignmentExpression = function (node, parent, file) {
+  if (parent.type === "ExpressionStatement") return;
+  if (!t.isPattern(node.left)) return;
+  throw file.errorWithNode(node, "AssignmentExpression destructuring outside of a ExpressionStatement is forbidden due to current 6to5 limitations");
+};
+
 exports.VariableDeclaration = function (node, parent, file, scope) {
   if (t.isForInStatement(parent) || t.isForOfStatement(parent)) return;
 

lib/6to5/transformation/transformers/for-of.js

@@ -5,17 +5,17 @@ exports.ForOfStatement = function (node, parent, file, scope) {
   var left = node.left;
   var declar;
 
-  var stepKey = t.identifier(file.generateUid("step", scope));
-  var stepValueId = t.memberExpression(stepKey, t.identifier("value"));
+  var stepKey   = t.identifier(file.generateUid("step", scope));
+  var stepValue = t.memberExpression(stepKey, t.identifier("value"));
 
   if (t.isIdentifier(left)) {
-    declar = t.expressionStatement(t.assignmentExpression("=", left, stepValueId));
+    declar = t.expressionStatement(t.assignmentExpression("=", left, stepValue));
   } else if (t.isVariableDeclaration(left)) {
     declar = t.variableDeclaration(left.kind, [
-      t.variableDeclarator(left.declarations[0].id, stepValueId)
+      t.variableDeclarator(left.declarations[0].id, stepValue)
     ]);
   } else {
-    return;
+    throw file.errorWithNode(left, "Unknown node type " + left.type + " in ForOfStatement");
   }
 
   var node2 = util.template("for-of", {

lib/6to5/transformation/transformers/generator-comprehension.js

@@ -0,0 +1,15 @@
+var arrayComprehension = require("./array-comprehension");
+var t                  = require("../../types");
+
+exports.ComprehensionExpression = function (node) {
+  if (!node.generator) return;
+
+  var body = [];
+  var container = t.functionExpression(null, [], t.blockStatement(body), true);
+
+  body.push(arrayComprehension._build(node, function () {
+    return t.expressionStatement(t.yieldExpression(node.body));
+  }));
+
+  return t.callExpression(container, []);
+};

lib/6to5/transformation/transformers/let-scoping.js

@@ -132,7 +132,7 @@ LetScoping.prototype.run = function () {
 
 /**
  * There are no let references accessed within a closure so we can just traverse
- * through this block and replace all references that exist in a high scope to
+ * through this block and replace all references that exist in a higher scope to
  * their uids.
  */
 
@@ -211,7 +211,8 @@ LetScoping.prototype.getInfo = function () {
 /**
  * If we're inside of a `For*Statement` then traverse it and check if it has one
  * of the following node types `ReturnStatement`, `BreakStatement`,
- * `ContinueStatement` and replace it with a return value we can track later on.
+ * `ContinueStatement` and replace it with a return value that we can track
+ * later on.
  *
  * @returns {Object}
  */
@@ -251,7 +252,7 @@ LetScoping.prototype.checkFor = function () {
 
 /**
  * Hoist all var declarations in this block to before it so they retain scope
- * once we wrap everything is in a closure.
+ * once we wrap everything in a closure.
  */
 
 LetScoping.prototype.hoistVarDeclarations = function () {

lib/6to5/transformation/transformers/spread.js

@@ -1,14 +1,13 @@
-var util = require("../../util");
-var t    = require("../../types");
-var _    = require("lodash");
+var t = require("../../types");
+var _ = require("lodash");
 
-var getSpreadLiteral = function (spread, file) {
+var getSpreadLiteral = function (spread) {
   var literal = spread.argument;
   if (!t.isArrayExpression(literal)) {
-    literal = util.template("call", {
-      OBJECT: file.addDeclaration("slice"),
-      CONTEXT: literal
-    });
+    literal = t.callExpression(
+      t.memberExpression(t.identifier("Array"), t.identifier("from")),
+      [literal]
+    );
   }
   return literal;
 };
@@ -24,7 +23,7 @@ var hasSpread = function (nodes) {
   return has;
 };
 
-var build = function (props, file) {
+var build = function (props) {
   var nodes = [];
 
   var _props = [];
@@ -38,7 +37,7 @@ var build = function (props, file) {
   _.each(props, function (prop) {
     if (t.isSpreadElement(prop)) {
       push();
-      nodes.push(getSpreadLiteral(prop, file));
+      nodes.push(getSpreadLiteral(prop));
     } else {
       _props.push(prop);
     }
@@ -49,11 +48,11 @@ var build = function (props, file) {
   return nodes;
 };
 
-exports.ArrayExpression = function (node, parent, file) {
+exports.ArrayExpression = function (node) {
   var elements = node.elements;
   if (!hasSpread(elements)) return;
 
-  var nodes = build(elements, file);
+  var nodes = build(elements);
   var first = nodes.shift();
 
   if (!nodes.length) return first;
@@ -61,7 +60,7 @@ exports.ArrayExpression = function (node, parent, file) {
   return t.callExpression(t.memberExpression(first, t.identifier("concat")), nodes);
 };
 
-exports.CallExpression = function (node, parent, file) {
+exports.CallExpression = function (node) {
   var args = node.arguments;
   if (!hasSpread(args)) return;
 
@@ -69,7 +68,7 @@ exports.CallExpression = function (node, parent, file) {
 
   node.arguments = [];
 
-  var nodes = build(args, file);
+  var nodes = build(args);
   var first = nodes.shift();
 
   if (nodes.length) {
@@ -96,3 +95,19 @@ exports.CallExpression = function (node, parent, file) {
 
   node.arguments.unshift(contextLiteral);
 };
+
+exports.NewExpression = function (node, parent, file) {
+  var args = node.arguments;
+  if (!hasSpread(args)) return;
+
+  var nodes = build(args);
+  var first = nodes.shift();
+
+  if (nodes.length) {
+    args = t.callExpression(t.memberExpression(first, t.identifier("concat")), nodes);
+  } else {
+    args = first;
+  }
+
+  return t.callExpression(file.addDeclaration("apply-constructor"), [node.callee, args]);
+};

lib/6to5/types/alias-keys.json

@@ -42,5 +42,6 @@
   "ObjectPattern": ["Pattern"],
   "ArrayPattern":  ["Pattern"],
 
-  "Property": ["UserWhitespacable"]
+  "Property": ["UserWhitespacable"],
+  "XJSElement": ["UserWhitespacable"]
 }

lib/6to5/types/builder-keys.json

@@ -7,11 +7,12 @@
   "ConditionalExpression":   ["test", "consequent", "alternate"],
   "ExpressionStatement":     ["expression"],
   "File":                    ["program", "comments", "tokens"],
-  "FunctionExpression":      ["id", "params", "body"],
+  "FunctionExpression":      ["id", "params", "body", "generator"],
   "Identifier":              ["name"],
   "IfStatement":             ["test", "consequent", "alternate"],
   "Literal":                 ["value"],
   "MemberExpression":        ["object", "property", "computed"],
+  "NewExpression":           ["callee", "arguments"],
   "ObjectExpression":        ["properties"],
   "ParenthesizedExpression": ["expression"],
   "Program":                 ["body"],

lib/6to5/types/index.js

@@ -106,6 +106,10 @@ t.ensureBlock = function (node) {
 };
 
 t.toStatement = function (node, ignore) {
+  if (t.isStatement(node)) {
+    return node;
+  }
+
   var mustHaveId = false;
   var newType;
 
@@ -115,8 +119,6 @@ t.toStatement = function (node, ignore) {
   } else if (t.isFunction(node)) {
     mustHaveId = true;
     newType = "FunctionDeclaration";
-  } else if (t.isStatement(node)) {
-    newType = node.type;
   }
 
   if (mustHaveId && !node.id) {

lib/6to5/util.js

@@ -244,7 +244,7 @@ exports.parse = function (opts, code, callback) {
   }
 };
 
-exports.parseNoProperties = function (loc, code) {
+exports.parseTemplate = function (loc, code) {
   var ast = exports.parse({ filename: loc }, code).program;
   return traverse.removeProperties(ast);
 };
@@ -266,7 +266,7 @@ var loadTemplates = function () {
     var loc  = templatesLoc + "/" + name;
     var code = fs.readFileSync(loc, "utf8");
 
-    templates[key] = exports.parseNoProperties(loc, code);
+    templates[key] = exports.parseTemplate(loc, code);
   });
 
   return templates;

package.json

@@ -1,7 +1,7 @@
 {
   "name": "6to5",
   "description": "Turn ES6 code into readable vanilla ES5 with source maps",
-  "version": "1.12.2",
+  "version": "1.12.9",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://github.com/6to5/6to5",
   "repository": {
@@ -44,11 +44,11 @@
     "es6-symbol": "0.1.1",
     "regexpu": "0.3.0",
     "source-map": "0.1.40",
-    "regenerator-6to5": "https://github.com/6to5/regenerator-6to5/archive/62d1bfcb331dcf0bbcdbbee8043da0c6408f09cf.tar.gz",
+    "regenerator-6to5": "https://github.com/6to5/regenerator-6to5/archive/75925940a7bb67d1ee8afec36b6d6eec072fb47c.tar.gz",
     "chokidar": "0.10.5",
     "source-map-support": "0.2.8",
     "esutils": "1.1.4",
-    "acorn-6to5": "https://github.com/6to5/acorn-6to5/archive/0384a0d51f630f66ed591769c1765581a17d2124.tar.gz",
+    "acorn-6to5": "https://github.com/6to5/acorn-6to5/archive/a6c34ba73e215bd16ee585f6794f6a6587820c58.tar.gz",
     "estraverse": "^1.7.0"
   },
   "devDependencies": {

test/fixtures/generation/basic/array-comprehensions/actual.js

@@ -1,3 +0,0 @@
-var multiples = [for (num of nums) num * num];
-var multiples = [for (num of nums) for (num2 of nums) num * num];
-var multiples = [for (num of nums) if (num > 5) num * num];

test/fixtures/generation/basic/array-comprehensions/expected.js

@@ -1,3 +0,0 @@
-var multiples = [for (num of nums) num * num];
-var multiples = [for (num of nums) for (num2 of nums) num * num];
-var multiples = [for (num of nums) if (num > 5) num * num];

test/fixtures/generation/basic/arrays/actual.js

@@ -1 +0,0 @@
-var foo = [1, 2, 3];

test/fixtures/generation/basic/arrays/expected.js

@@ -1 +0,0 @@
-var foo = [1, 2, 3];

test/fixtures/generation/basic/template-literals/actual.js

@@ -1,17 +0,0 @@
-var foo = `i
-am a multiline string`;
-
-var foo = `i am also
-   a multiline string
-foobar`;
-
-var foo = `im a single line string`;
-
-var foo = tagit`i
-am a multiline string`;
-
-var foo = tagit`i am also
-   a multiline string
-foobar`;
-
-var foo = tagit`im a single line string`;

test/fixtures/generation/basic/template-literals/expected.js

@@ -1,17 +0,0 @@
-var foo = `i
-am a multiline string`;
-
-var foo = `i am also
-   a multiline string
-foobar`;
-
-var foo = `im a single line string`;
-
-var foo = tagit`i
-am a multiline string`;
-
-var foo = tagit`i am also
-   a multiline string
-foobar`;
-
-var foo = tagit`im a single line string`;

test/fixtures/generation/comments/.comment-only/actual.js

@@ -2,3 +2,5 @@
 /**/
 /*
 */
+
+test

test/fixtures/generation/comments/simple-a-lot-of-line-comment/expected.js

@@ -20,8 +20,11 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 // THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+
 function test() {}
 
+
+
 // Copyright (C) 2012 Yusuke Suzuki <utatane.tea@gmail.com>
 //
 // Redistribution and use in source and binary forms, with or without

test/fixtures/generation/harmony-edgecase/exports/expected.js

@@ -4,6 +4,6 @@ export { a as b, c as d } from "hello";
 export { a as b, c as d };
 export {};
 export default i = 20;
-export function test() {};
+export function test() {}
 export var i = 20;
 export let i = 42;

test/fixtures/generation/types/ArrayExpression-ArrayPattern/actual.js

@@ -0,0 +1,5 @@
+[a, b, c];
+[[], [b, c], []];
+[a,, b,];
+[a,,,, b];
+[a, b,, c];

test/fixtures/generation/types/ArrayExpression-ArrayPattern/expected.js

@@ -0,0 +1,5 @@
+[a, b, c];
+[[], [b, c], []];
+[a,, b];
+[a,,,, b];
+[a, b,, c];

test/fixtures/generation/types/ArrowFunctionExpression/actual.js

@@ -0,0 +1,4 @@
+var foo = x => x * x;
+var foo = (a, b) => a * b;
+var foo = async x => x * x;
+var foo = async (a, b) => a * b;

test/fixtures/generation/types/ArrowFunctionExpression/expected.js

@@ -0,0 +1,4 @@
+var foo = x => x * x;
+var foo = (a, b) => a * b;
+var foo = async x => x * x;
+var foo = async (a, b) => a * b;

test/fixtures/generation/types/AssignmentExpression-BinaryExpression-LogicalExpression/actual.js

@@ -0,0 +1,3 @@
+foo === bar;
+foo + bar;
+foo = bar;

test/fixtures/generation/types/AssignmentExpression-BinaryExpression-LogicalExpression/expected.js

@@ -0,0 +1,3 @@
+foo === bar;
+foo + bar;
+foo = bar;

test/fixtures/generation/types/AwaitExpression/actual.js

@@ -0,0 +1,7 @@
+async function foo() {
+  await bar();
+}
+
+async function bar() {
+  await* foo();
+}

test/fixtures/generation/types/AwaitExpression/expected.js

@@ -0,0 +1,7 @@
+async function foo() {
+  await bar();
+}
+
+async function bar() {
+  await* foo();
+}

test/fixtures/generation/types/BlockStatement/actual.js

@@ -0,0 +1,5 @@
+{}
+
+{
+  foo();
+}

test/fixtures/generation/types/BlockStatement/expected.js

@@ -0,0 +1,5 @@
+{}
+
+{
+  foo();
+}

test/fixtures/generation/types/BreakStatement/actual.js

@@ -0,0 +1,7 @@
+for (var i in foo) {
+  break;
+}
+
+foo: for (var i in foo) {
+  break foo;
+}

test/fixtures/generation/types/BreakStatement/expected.js

@@ -0,0 +1,7 @@
+for (var i in foo) {
+  break;
+}
+
+foo: for (var i in foo) {
+  break foo;
+}

test/fixtures/generation/types/CallExpression/actual.js

@@ -0,0 +1,5 @@
+foo();
+foo("foo");
+foo("foo", "bar");
+foo(bar());
+foo(bar("test"));

test/fixtures/generation/types/CallExpression/expected.js

@@ -0,0 +1,5 @@
+foo();
+foo("foo");
+foo("foo", "bar");
+foo(bar());
+foo(bar("test"));

test/fixtures/generation/types/ClassBody-MethodDefinition/actual.js

@@ -0,0 +1,13 @@
+class Foo {
+  async foo() {}
+  foo() {}
+  ["foo"]() {}
+  get foo() {}
+  set foo() {}
+
+  static async foo() {}
+  static foo() {}
+  static ["foo"]() {}
+  static get foo() {}
+  static set foo() {}
+}

test/fixtures/generation/types/ClassBody-MethodDefinition/expected.js

@@ -0,0 +1,13 @@
+class Foo {
+  async foo() {}
+  foo() {}
+  ["foo"]() {}
+  get foo() {}
+  set foo() {}
+
+  static async foo() {}
+  static foo() {}
+  static ["foo"]() {}
+  static get foo() {}
+  static set foo() {}
+}

test/fixtures/generation/types/ClassDeclaration/actual.js

@@ -0,0 +1,2 @@
+var foo = class Foo {};
+var foo = class Foo extends Bar {};

test/fixtures/generation/types/ClassDeclaration/expected.js

@@ -0,0 +1,2 @@
+var foo = class Foo {};
+var foo = class Foo extends Bar {};

test/fixtures/generation/types/ClassExpression/actual.js

@@ -0,0 +1,2 @@
+class Foo {}
+class Foo extends Bar {}

test/fixtures/generation/types/ClassExpression/expected.js

@@ -0,0 +1,2 @@
+class Foo {}
+class Foo extends Bar {}

test/fixtures/generation/types/ComprehensionBlock-ComprehensionExpression/actual.js

@@ -0,0 +1,9 @@
+[for (x of nums) x * x];
+[for (x of nums) if (x > 2) x * x];
+[for (nums of nums2) for (x of nums) x * x];
+[for (nums of nums2) for (x of nums) if (x > 2) x * x];
+
+(for (x of nums) x * x);
+(for (x of nums) if (x > 2) x * x);
+(for (nums of nums2) for (x of nums) x * x);
+(for (nums of nums2) for (x of nums) if (x > 2) x * x);

test/fixtures/generation/types/ComprehensionBlock-ComprehensionExpression/expected.js

@@ -0,0 +1,9 @@
+[for (x of nums) x * x];
+[for (x of nums) if (x > 2) x * x];
+[for (nums of nums2) for (x of nums) x * x];
+[for (nums of nums2) for (x of nums) if (x > 2) x * x];
+
+(for (x of nums) x * x);
+(for (x of nums) if (x > 2) x * x);
+(for (nums of nums2) for (x of nums) x * x);
+(for (nums of nums2) for (x of nums) if (x > 2) x * x);

test/fixtures/generation/types/ConditionalExpression/actual.js

@@ -0,0 +1 @@
+foo ? foo : bar;

test/fixtures/generation/types/ConditionalExpression/expected.js

@@ -0,0 +1 @@
+foo ? foo : bar;

test/fixtures/generation/types/ContinueStatement/actual.js

@@ -0,0 +1,7 @@
+for (var i in foo) {
+  continue;
+}
+
+foo: for (var i in foo) {
+  continue foo;
+}

test/fixtures/generation/types/ContinueStatement/expected.js

@@ -0,0 +1,7 @@
+for (var i in foo) {
+  continue;
+}
+
+foo: for (var i in foo) {
+  continue foo;
+}

test/fixtures/generation/types/DebuggerStatement/actual.js

@@ -0,0 +1 @@
+debugger;

test/fixtures/generation/types/DebuggerStatement/expected.js

@@ -0,0 +1 @@
+debugger;

test/fixtures/generation/types/DoWhileStatement/actual.js

@@ -0,0 +1,5 @@
+do {
+  test();
+} while (true);
+
+do {} while (true);

test/fixtures/generation/types/DoWhileStatement/expected.js

@@ -0,0 +1,5 @@
+do {
+  test();
+} while (true);
+
+do {} while (true);

test/fixtures/generation/types/EmptyStatement/actual.js

@@ -0,0 +1 @@
+;

test/fixtures/generation/types/EmptyStatement/expected.js

@@ -0,0 +1 @@
+;

test/fixtures/generation/types/ExportDeclaration-ExportSpecifier-ExportBatchSpecifier/actual.js

@@ -0,0 +1,27 @@
+export default 42;
+export default {};
+export default [];
+export default foo;
+export default function () {};
+export default class {};
+export default function foo() {};
+export default class Foo {};
+export * from "foo";
+export { foo } from "foo";
+export { foo, bar } from "foo";
+export { foo as bar } from "foo";
+export { foo as default } from "foo";
+export { foo as default, bar } from "foo";
+export { foo };
+export { foo, bar };
+export { foo as bar };
+export { foo as default };
+export { foo as default, bar };
+export var foo = 1;
+export var foo2 = function () {};
+export var foo3;
+export let foo4 = 2;
+export let foo5;
+export const foo6 = 3;
+export function foo7() {}
+export class foo8 {}