v1.13.0

Fix runtime injection in Web Worker.

.hound.yml

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

CHANGELOG.md

@@ -1,3 +1,9 @@
+# 1.13.0
+
+ * Put experimental ES7 features behind a flag `--experimental` and `experimental` option.
+ * Constructor speed performance increase. Thanks [@RReverser](https://github.com/RReverser).
+ * Use `self` instead of `window` in the optional 6to5 runtime. Thanks [@RReverser](https://github.com/RReverser).
+
 # 1.12.26
 
  * Support computed property destructuring.

bin/6to5/index.js

@@ -11,6 +11,7 @@ commander.option("-s, --source-maps", "Save source map alongside the compiled co
 commander.option("-f, --filename [filename]", "Filename to use when reading from stdin - this will be used in source-maps, errors etc [stdin]", "stdin");
 commander.option("-w, --watch", "Recompile files on changes");
 commander.option("-r, --runtime", "Replace 6to5 declarations with references to a runtime");
+commander.option("-e, --experimental", "Enable experimental support for proposed ES7 features");
 
 commander.option("-m, --modules [modules]", "Module formatter type to use [common]", "common");
 commander.option("-w, --whitelist [whitelist]", "Whitelist of transformers to ONLY use", util.list);
@@ -87,11 +88,12 @@ if (errors.length) {
 
 exports.opts = {
   sourceMapName: commander.outFile,
+  amdModuleIds:  commander.amdModuleIds,
+  experimental:  commander.experimental,
   blacklist:     commander.blacklist,
   whitelist:     commander.whitelist,
   sourceMap:     commander.sourceMaps || commander.sourceMapsInline,
   comments:      !commander.removeComments,
-  amdModuleIds:   commander.amdModuleIds,
   runtime:       commander.runtime,
   modules:       commander.modules
 };

bin/_6to5-node

@@ -8,10 +8,11 @@ var util      = require("../lib/6to5/util");
 var vm        = require("vm");
 var _         = require("lodash");
 
-commander.option("-e, --eval [script]", "evaluate script");
-commander.option("-p, --print", "evaluate script and print result");
-commander.option("-i, --ignore [regex]", "ignore all files that match this regex when using the require hook");
-commander.option("-x, --extensions [extensions]", "list of extensions to hook into [.es6,.js]", util.list);
+commander.option("-e, --eval [script]", "Evaluate script");
+commander.option("-p, --print", "Evaluate script and print result");
+commander.option("-i, --ignore [regex]", "Ignore all files that match this regex when using the require hook");
+commander.option("-x, --extensions [extensions]", "List of extensions to hook into [.es6,.js]");
+commander.option("-r, --experimental", "Enable experimental support for proposed ES7 features");
 
 var pkg = require("../package.json");
 commander.version(pkg.version);
@@ -20,17 +21,11 @@ commander.parse(process.argv);
 
 //
 
-var registerOpts = {};
-
-if (commander.ignore) {
-  registerOpts.ignoreRegex = new RegExp(commander.ignore);
-}
-
-if (commander.extensions && commander.extensions.length) {
-  registerOpts.extensions = commander.extensions;
-}
-
-to5.register(registerOpts);
+to5.register({
+  experimental: commander.experimental,
+  extensions:   commander.extensions,
+  ignore:       commander.ignore
+});
 
 //
 

doc/caveats.md

@@ -5,6 +5,16 @@
 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.
 
+### Async/Comprehensions
+
+[Experimental support](usage.md#experimental) must be enabled for these proposed
+ES7 features to work.
+
+### Array comprehension/Array destructuring/Spread
+
+An [ES6 polyfill](polyfill.md) is required. More specifically a polyfill for
+`Array.from`.
+
 ## Classes
 
 Built-in classes such as `Date`, `Array` and `DOM` cannot be subclassed due to
@@ -31,13 +41,13 @@ class Bar extends Foo {
 }
 ```
 
+## Constructor spread
+
+Constructor spreads do not currently support built-ins. ie.
+`new Array(...items)`.
+
 ## 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.
-
-### Array destructuring / Spread
-
-An [ES6 polyfill](polyfill.md) is required for spread and array destructuring.
-More specifically a polyfill for `Array.from`.

doc/features.md

@@ -1,6 +1,6 @@
 # Features
 
-## Array comprehension
+## Array comprehension ([experimental](usage.md#experimental))
 
 ```javascript
 var results = [for (c of customers) if (c.city == "Seattle") { name: c.name, age: c.age }]
@@ -31,7 +31,7 @@ var bob = {
 };
 ```
 
-## Async functions
+## Async functions ([experimental](usage.md#experimental))
 
 ```javascript
 async function chainAnimationsAsync(elem, animations) {
@@ -150,7 +150,7 @@ for (var n of fibonacci()) {
 }
 ```
 
-## Generator comprehension
+## Generator comprehension ([experimental](usage.md#experimental))
 
 ```javascript
 var nums = [1, 2, 3, 4, 5, 6];

doc/index.md

@@ -3,7 +3,7 @@
  - **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).
+ - **Compact** - maps directly to the equivalent ES5 with **no runtime**[\*](caveats.md).
 
 ## Installation
 
@@ -31,8 +31,8 @@ And it doesn't end here! To see all the ways you can use 6to5, check out the
 
 ## [Features](features.md)
 
- - [Array comprehension](features.md#array-comprehension)
- - [Async functions](features.md#async-functions)
+ - [Array comprehension](features.md#array-comprehension) ([experimental](usage.md#experimental))
+ - [Async functions](features.md#async-functions) ([experimental](usage.md#experimental))
  - [Arrow functions](features.md#arrow-functions)
  - [Classes](features.md#classes)
  - [Computed property names](features.md#computed-property-names)
@@ -41,7 +41,7 @@ And it doesn't end here! To see all the ways you can use 6to5, check out the
  - [Destructuring](features.md#destructuring)
  - [For-of](features.md#for-of)
  - [Generators](features.md#generators)
- - [Generator comprehension](features.md#generator-comprehension)
+ - [Generator comprehension](features.md#generator-comprehension) ([experimental](usage.md#experimental))
  - [Let scoping](features.md#let-scoping)
  - [Modules](features.md#modules)
  - [Numeric literals](features.md#numeric-literals)

doc/usage.md

@@ -135,7 +135,11 @@ to5.transformFile("filename.js", options, function (err, result) {
 
   // Output comments in generated output
   // Default: true
-  comments: false
+  comments: false,
+
+  // Enable support for experimental ES7 features
+  // Default: false
+  experimental: true
 }
 ```
 
@@ -181,3 +185,11 @@ require("6to5/register")({
   extensions: [".js", ".es6"]
 });
 ```
+
+## Experimental
+
+6to5 also has experimental support for ES7 proposals. You can enable this with
+the `experimental: true` option when using the [Node API](#node) or
+`--experimental` when using the [CLI](#cli).
+
+**NOTE:** That these are subject to change as their proposal status progresses.

lib/6to5/file.js

@@ -25,15 +25,16 @@ File.normaliseOptions = function (opts) {
   opts = _.cloneDeep(opts || {});
 
   _.defaults(opts, {
-    whitespace: true,
-    blacklist:  [],
-    whitelist:  [],
-    sourceMap:  false,
-    comments:   true,
-    filename:   "unknown",
-    modules:    "common",
-    runtime:    false,
-    code:       true
+    experimental: false,
+    whitespace:   true,
+    blacklist:    [],
+    whitelist:    [],
+    sourceMap:    false,
+    comments:     true,
+    filename:     "unknown",
+    modules:      "common",
+    runtime:      false,
+    code:         true
   });
 
   // normalise windows path separators to unix

lib/6to5/register.js

@@ -57,24 +57,25 @@ blacklistTest("unicodeRegex", function () { new RegExp("foo", "u"); });
 
 //
 
-var ignoreRegex = /node_modules/;
+var transformOpts = {};
+var ignoreRegex   = /node_modules/;
 var onlyRegex;
-var whitelist   = [];
-var exts        = {};
-var maps        = {};
-var old         = require.extensions[".js"];
+var whitelist     = [];
+var exts          = {};
+var maps          = {};
+var old           = require.extensions[".js"];
 
 var loader = function (m, filename) {
   if ((ignoreRegex && ignoreRegex.test(filename)) || (onlyRegex && !onlyRegex.test(filename))) {
     return old.apply(this, arguments);
   }
 
-  var result = to5.transformFileSync(filename, {
+  var result = to5.transformFileSync(filename, _.extend({
     whitelist: whitelist,
     blacklist: blacklist,
     sourceMap: true,
     modules:   "commonInterop"
-  });
+  }, transformOpts));
 
   maps[filename] = result.map;
 
@@ -107,6 +108,5 @@ module.exports = function (opts) {
 
   if (opts.extensions) hookExtensions(util.arrayify(opts.extensions));
 
-  if (opts.blacklist) blacklist = util.arrayify(opts.blacklist);
-  if (opts.whitelist) whitelist = util.arrayify(opts.whitelist);
+  _.extend(transformOpts, opts);
 };

lib/6to5/runtime.js

@@ -8,15 +8,13 @@ module.exports = function (namespace) {
   namespace = t.identifier(t.toIdentifier(namespace || "to5Runtime"));
 
   var body      = [];
-  var container = t.functionExpression(null, [], t.blockStatement(body));
-  var tree      = t.program([t.expressionStatement(t.callExpression(container, []))]);
-
-  body.push(util.template("self-global", true));
+  var container = t.functionExpression(null, [t.identifier("global")], t.blockStatement(body));
+  var tree      = t.program([t.expressionStatement(t.callExpression(container, [util.template("self-global")]))]);
 
   body.push(t.variableDeclaration("var", [
     t.variableDeclarator(
       namespace,
-      t.assignmentExpression("=", t.memberExpression(t.identifier("self"), namespace), t.objectExpression([]))
+      t.assignmentExpression("=", t.memberExpression(t.identifier("global"), namespace), t.objectExpression([]))
     )
   ]));
 

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

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

lib/6to5/templates/self-global.js

@@ -1 +1 @@
-var self = typeof global === "undefined" ? window : global;
+typeof global === "undefined" ? self : global

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

@@ -2,16 +2,21 @@ var util = require("../../util");
 var t    = require("../../types");
 var _    = require("lodash");
 
-var singleArrayExpression = function (node) {
+var single = function (node) {
   var block = node.blocks[0];
 
   var templateName = "array-expression-comprehension-map";
   if (node.filter) templateName = "array-expression-comprehension-filter";
 
+  var right = block.right;
+  if (!t.isArrayExpression(right)) {
+    right = util.template("array-from", { VALUE: right });
+  }
+
   var result = util.template(templateName, {
     STATEMENT: node.body,
     FILTER:    node.filter,
-    ARRAY:     block.right,
+    ARRAY:     right,
     KEY:       block.left
   });
 
@@ -73,8 +78,8 @@ exports._build = function (node, buildBody) {
 exports.ComprehensionExpression = function (node, parent, file) {
   if (node.generator) return;
 
-  if (node.blocks.length === 1 && t.isArrayExpression(node.blocks[0].right)) {
-    return singleArrayExpression(node);
+  if (node.blocks.length === 1) {
+    return single(node);
   } else {
     return multiple(node, file);
   }

lib/6to5/util.js

@@ -218,7 +218,7 @@ exports.parse = function (opts, code, callback) {
     var ast = acorn.parse(code, {
       allowReturnOutsideFunction: true,
       preserveParens:             true,
-      ecmaVersion:                Infinity,
+      ecmaVersion:                opts.experimental ? 7 : 6,
       strictMode:                 true,
       onComment:                  comments,
       locations:                  true,

package.json

@@ -1,7 +1,7 @@
 {
   "name": "6to5",
   "description": "Turn ES6 code into readable vanilla ES5 with source maps",
-  "version": "1.12.26",
+  "version": "1.13.0",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://github.com/6to5/6to5",
   "repository": {

test/fixtures/transformation/array-comprehension/options.json

@@ -0,0 +1,3 @@
+{
+  "experimental": true
+}

test/fixtures/transformation/array-comprehension/single-if/actual.js

@@ -0,0 +1 @@
+var arr = [for (i of nums) if (i > 1) i * i];

test/fixtures/transformation/array-comprehension/single-if/expected.js

@@ -0,0 +1,7 @@
+"use strict";
+
+var arr = Array.from(nums).filter(function (i) {
+  return i > 1;
+}).map(function (i) {
+  return i * i;
+});

test/fixtures/transformation/array-comprehension/single/actual.js

@@ -0,0 +1 @@
+var arr = [for (i of nums) i * i];

test/fixtures/transformation/array-comprehension/single/expected.js

@@ -0,0 +1,5 @@
+"use strict";
+
+var arr = Array.from(nums).map(function (i) {
+  return i * i;
+});

test/fixtures/transformation/async/options.json

@@ -1,3 +1,4 @@
 {
-  "asyncExec": true
+  "asyncExec": true,
+  "experimental": true
 }

test/fixtures/transformation/generator-comprehension/options.json

@@ -0,0 +1,3 @@
+{
+  "experimental": true
+}

test/fixtures/transformation/spread/new-expression/expected.js

@@ -1,11 +1,11 @@
 "use strict";
 
 var _applyConstructor = function (Constructor, args) {
-  var bindArgs = [null].concat(args);
+  var instance = Object.create(Constructor.prototype);
 
-  var Factory = Constructor.bind.apply(Constructor, bindArgs);
+  Constructor.apply(instance, args);
 
-  return new Factory();
+  return instance;
 };
 
 _applyConstructor(Numbers, Array.from(nums));

test/generation.js

@@ -26,7 +26,7 @@ _.each(helper.get("generation"), function (testSuite) {
         var expect = task.expect;
         var actual = task.actual;
 
-        var actualAst  = util.parse({ filename: actual.loc }, actual.code);
+        var actualAst  = util.parse({ filename: actual.loc, experimental: true }, actual.code);
         var actualCode = generate(actualAst, null, actual.code).code;
 
         chai.expect(actualCode).to.equal(expect.code, actual.loc + " !== " + expect.loc);