v2.4.0

CHANGELOG.md

@@ -2,6 +2,19 @@
 
 Gaps between patch versions are faulty/broken releases.
 
+## 2.4.0
+
+ * Use a closure always for classes with a super.
+ * Always use native loops for array comprehensions.
+ * Allow `yield` inside of comprehensions.
+ * Add optional `bluebirdCoroutine` transformer.
+ * Add optional `asyncToGenerator` transformer.
+ * Move `useStrict` transformer to before `_moduleFormatter` causing `"use strict";` to always be placed the very top.
+
+## 2.3.2
+
+ * Add parens on expressions with trailing comments.
+
 ## 2.3.1
 
  * Add `undefinedToVoid` optional transformer.

lib/6to5/file.js

@@ -27,7 +27,12 @@ File.declarations = [
   "object-without-properties",
   "has-own",
   "slice",
-  "define-property"
+  "define-property",
+  "async-to-generator"
+];
+
+File.excludeDeclarationsFromRuntime = [
+  "async-to-generator"
 ];
 
 File.normaliseOptions = function (opts) {
@@ -95,6 +100,10 @@ File.prototype.getTransformers = function () {
   _.each(transform.transformers, function (transformer) {
     if (transformer.canRun(file)) {
       transformers.push(transformer);
+
+      if (transformer.manipulateOptions) {
+        transformer.manipulateOptions(file.opts, file);
+      }
     }
   });
 
@@ -144,6 +153,12 @@ File.prototype.parseShebang = function (code) {
   return code;
 };
 
+File.prototype.addImport = function (id, source) {
+  var specifiers = [t.importSpecifier(t.identifier("default"), id)];
+  var declar = t.importDeclaration(specifiers, t.literal(source));
+  this.ast.program.body.unshift(declar);
+};
+
 File.prototype.addDeclaration = function (name) {
   if (!_.contains(File.declarations, name)) {
     throw new ReferenceError("unknown declaration " + name);
@@ -156,7 +171,7 @@ File.prototype.addDeclaration = function (name) {
 
   var ref;
   var runtimeNamespace = this.opts.runtime;
-  if (runtimeNamespace) {
+  if (runtimeNamespace && !_.contains(File.excludeDeclarationsFromRuntime, name)) {
     name = t.identifier(t.toIdentifier(name));
     return t.memberExpression(t.identifier(runtimeNamespace), name);
   } else {

lib/6to5/generation/generator.js

@@ -148,6 +148,11 @@ CodeGenerator.prototype.print = function (node, parent, opts) {
   };
 
   if (this[node.type]) {
+    // only compute if this node needs parens if our parent has been changed
+    // since acorn would've wrapped us in a ParanthesizedExpression
+    var needsParens = n.needsParens(node, parent);
+    if (needsParens) this.push("(");
+
     this.printLeadingComments(node, parent);
 
     newline(true);
@@ -155,11 +160,6 @@ CodeGenerator.prototype.print = function (node, parent, opts) {
     if (opts.before) opts.before();
     this.map.mark(node, "start");
 
-    // only compute if this node needs parens if our parent has been changed
-    // since acorn would've wrapped us in a ParanthesizedExpression
-    var needsParens = n.needsParens(node, parent);
-    if (needsParens) this.push("(");
-
     this[node.type](node, this.buildPrint(node), parent);
 
     if (needsParens) this.push(")");

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

@@ -60,6 +60,10 @@ Node.prototype.needsParens = function () {
 
   if (!parent) return false;
 
+  if (t.isExpression(node) && node.leadingComments && node.leadingComments.length) {
+    return true;
+  }
+
   if (t.isNewExpression(parent) && parent.callee === node) {
     return t.isCallExpression(node) || _.some(node, function (val) {
       return t.isCallExpression(val);

lib/6to5/runtime-generator.js

@@ -19,6 +19,10 @@ module.exports = function (namespace) {
   ]));
 
   _.each(File.declarations, function (name) {
+    if (_.contains(File.excludeDeclarationsFromRuntime, name)) {
+      return false;
+    }
+
     var key = t.identifier(t.toIdentifier(name));
     body.push(t.expressionStatement(
       t.assignmentExpression("=", t.memberExpression(namespace, key), util.template(name))

lib/6to5/transformation/templates/array-expression-comprehension-filter.js

@@ -1,5 +0,0 @@
-ARRAY.filter(function (KEY) {
-  return FILTER;
-}).map(function (KEY) {
-  return STATEMENT;
-});

lib/6to5/transformation/templates/array-expression-comprehension-map.js

@@ -1,3 +0,0 @@
-ARRAY.map(function (KEY) {
-  return STATEMENT;
-});

lib/6to5/transformation/templates/async-to-generator.js

@@ -0,0 +1,37 @@
+(function (fn) {
+  return function () {
+    var gen = fn.apply(this, arguments);
+
+    return new Promise(function (resolve, reject) {
+      function step(getNext) {
+        var next;
+
+        try {
+          next = getNext();
+        } catch(e) {
+          reject(e);
+          return;
+        }
+
+        if (next.done) {
+          resolve(next.value);
+          return;
+        }
+
+        Promise.resolve(next.value).then(function (v) {
+          step(function () {
+            return gen.next(v);
+          });
+        }, function (e) {
+          step(function () {
+            return gen["throw"](e);
+          });
+        });
+      }
+
+      step(function () {
+        return gen.next();
+      });
+    });
+  }
+})

lib/6to5/transformation/transform.js

@@ -49,6 +49,9 @@ _.each({
   memoizationOperator:       require("./transformers/playground-memoization-operator"),
   objectGetterMemoization:   require("./transformers/playground-object-getter-memoization"),
 
+  asyncToGenerator:          require("./transformers/optional-async-to-generator"),
+  bluebirdCoroutines:        require("./transformers/optional-bluebird-coroutines"),
+
   react:                     require("./transformers/react"),
   modules:                   require("./transformers/es6-modules"),
   propertyNameShorthand:     require("./transformers/es6-property-name-shorthand"),
@@ -85,8 +88,8 @@ _.each({
 
   // wrap up
   _aliasFunctions:           require("./transformers/_alias-functions"),
-  useStrict:                 require("./transformers/use-strict"),
   _moduleFormatter:          require("./transformers/_module-formatter"),
+  useStrict:                 require("./transformers/use-strict"),
 
   // spec
   specPropertyLiterals:         require("./transformers/spec-property-literals"),

lib/6to5/transformation/transformer.js

@@ -5,11 +5,12 @@ var t        = require("../types");
 var _        = require("lodash");
 
 function Transformer(key, transformer, opts) {
-  this.experimental = !!transformer.experimental;
-  this.transformer  = Transformer.normalise(transformer);
-  this.optional     = !!transformer.optional;
-  this.opts         = opts || {};
-  this.key          = key;
+  this.manipulateOptions = transformer.manipulateOptions;
+  this.experimental      = !!transformer.experimental;
+  this.transformer       = Transformer.normalise(transformer);
+  this.optional          = !!transformer.optional;
+  this.opts              = opts || {};
+  this.key               = key;
 }
 
 Transformer.normalise = function (transformer) {

lib/6to5/transformation/transformers/es6-classes.js

@@ -21,7 +21,7 @@ exports.ClassDeclaration = function (node, parent, file, scope) {
       });
       return t.assignmentExpression("=", node.id, newNode);
     } else {
-      // likely has a PrivateDeclaration etc
+      // has a super class or PrivateDeclaration etc
       return t.variableDeclaration("let", [
         t.variableDeclarator(node.id, newNode)
       ]);
@@ -85,7 +85,8 @@ Class.prototype.run = function () {
 
   //
 
-  if (superName && t.isDynamic(superName)) {
+  if (superName) {
+    this.closure = true;
     // so we're only evaluating it once
     var superRefName = "super";
     if (className) superRefName = className.name + "Super";
@@ -95,13 +96,8 @@ Class.prototype.run = function () {
       t.variableDeclarator(superRef, superName)
     ]));
     superName = superRef;
-  }
 
-  this.superName = superName;
-
-  //
-
-  if (superName) {
+    this.superName = superName;
     body.push(t.expressionStatement(t.callExpression(file.addDeclaration("inherits"), [className, superName])));
   }
 

lib/6to5/transformation/transformers/es7-array-comprehension.js

@@ -1,43 +1,25 @@
-var util = require("../../util");
-var t    = require("../../types");
+var traverse = require("../../traverse");
+var util     = require("../../util");
+var t        = require("../../types");
 
 exports.experimental = true;
 
-var single = function (node, file) {
-  var block = node.blocks[0];
-
-  var templateName = "array-expression-comprehension-map";
-  if (node.filter) templateName = "array-expression-comprehension-filter";
-
-  var result = util.template(templateName, {
-    STATEMENT: node.body,
-    FILTER:    node.filter,
-    ARRAY:     file.toArray(block.right),
-    KEY:       block.left
-  });
-
-  var aliasPossibles = [result.callee.object, result];
-  for (var i in aliasPossibles) {
-    var call = aliasPossibles[i];
-    if (t.isCallExpression(call)) {
-      call.arguments[0]._aliasFunction = true;
-    }
-  }
-
-  return result;
-};
-
-var multiple = function (node, file) {
+var build = function (node, file) {
   var uid = file.generateUidIdentifier("arr");
 
   var container = util.template("array-comprehension-container", {
     KEY: uid
   });
-  container.callee.expression._aliasFunction = true;
+  container.callee._aliasFunction = true;
 
   var block = container.callee.body;
   var body  = block.body;
 
+  if (traverse.hasType(node, "YieldExpression", t.FUNCTION_TYPES)) {
+    container.generator = true;
+    container = t.yieldExpression(container, true);
+  }
+
   var returnStatement = body.pop();
 
   body.push(exports._build(node, function () {
@@ -76,9 +58,5 @@ exports._build = function (node, buildBody) {
 exports.ComprehensionExpression = function (node, parent, file) {
   if (node.generator) return;
 
-  if (node.blocks.length === 1) {
-    return single(node, file);
-  } else {
-    return multiple(node, file);
-  }
+  return build(node, file);
 };

lib/6to5/transformation/transformers/optional-async-to-generator.js

@@ -0,0 +1,14 @@
+var bluebirdCoroutines = require("./optional-bluebird-coroutines");
+var t                  = require("../../types");
+
+exports.optional = true;
+
+exports.manipulateOptions = bluebirdCoroutines.manipulateOptions;
+
+exports.Function = function (node, parent, file) {
+  if (!node.async || node.generator) return;
+
+  bluebirdCoroutines._Function(node);
+
+  return t.callExpression(file.addDeclaration("async-to-generator"), [node]);
+};

lib/6to5/transformation/transformers/optional-bluebird-coroutines.js

@@ -0,0 +1,34 @@
+var traverse = require("../../traverse");
+var t        = require("../../types");
+
+exports.manipulateOptions = function (opts) {
+  opts.experimental = true;
+  opts.blacklist.push("generators");
+};
+
+exports.optional = true;
+
+exports._Function = function (node) {
+  node.async = false;
+  node.generator = true;
+
+  traverse(node, {
+    enter: function (node) {
+      if (t.isFunction(node)) this.stop();
+
+      if (t.isAwaitExpression(node)) {
+        node.type = "YieldExpression";
+      }
+    }
+  });
+};
+
+exports.Function = function (node, parent, file) {
+  if (!node.async || node.generator) return;
+
+  exports._Function(node);
+
+  var id = t.identifier("Bluebird");
+  file.addImport(id, "bluebird");
+  return t.callExpression(t.memberExpression(id, t.identifier("coroutine")), [node]);
+};

lib/6to5/transformation/transformers/optional-core-aliasing.js

@@ -9,9 +9,7 @@ exports.optional = true;
 exports.ast = {
   enter: function (ast, file) {
     file._coreId = file.generateUidIdentifier("core");
-    var specifiers = [t.importSpecifier(t.identifier("default"), file._coreId)];
-    var declar = t.importDeclaration(specifiers, t.literal("core-js/library"));
-    ast.program.body.unshift(declar);
+    file.addImport(file._coreId, "core-js/library");
   },
 
   exit: function (ast, file) {

lib/6to5/traverse/index.js

@@ -107,6 +107,11 @@ function traverse(parent, opts, scope) {
 
       if (updated) {
         parent[key] = _.flatten(parent[key]);
+
+        if (key === "body") {
+          // we can safely compact this
+          parent[key] = _.compact(parent[key]);
+        }
       }
     } else {
       handle(parent, key);

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

@@ -17,23 +17,23 @@
   "ExportDeclaration":   ["Statement", "Declaration"],
   "ImportDeclaration":   ["Statement", "Declaration"],
 
-  "ArrowFunctionExpression": ["Scope", "Function"],
+  "ArrowFunctionExpression": ["Scope", "Function", "Expression"],
   "FunctionDeclaration":     ["Statement", "Declaration", "Scope", "Function"],
-  "FunctionExpression":      ["Scope", "Function"],
+  "FunctionExpression":      ["Scope", "Function", "Expression"],
 
   "BlockStatement": ["Statement", "Scope"],
   "Program":        ["Scope"],
   "CatchClause":    ["Scope"],
 
-  "LogicalExpression": ["Binary"],
-  "BinaryExpression":  ["Binary"],
+  "LogicalExpression": ["Binary", "Expression"],
+  "BinaryExpression":  ["Binary", "Expression"],
 
-  "UnaryExpression": ["UnaryLike"],
+  "UnaryExpression": ["UnaryLike", "Expression"],
   "SpreadProperty":  ["UnaryLike"],
   "SpreadElement":   ["UnaryLike"],
 
   "ClassDeclaration": ["Statement", "Declaration", "Class"],
-  "ClassExpression":  ["Class"],
+  "ClassExpression":  ["Class", "Expression"],
 
   "ForOfStatement": ["Statement", "For", "Scope", "Loop"],
   "ForInStatement": ["Statement", "For", "Scope", "Loop"],
@@ -43,5 +43,27 @@
   "ArrayPattern":  ["Pattern"],
 
   "Property": ["UserWhitespacable"],
-  "XJSElement": ["UserWhitespacable"]
+  "XJSElement": ["UserWhitespacable", "Expression"],
+
+  "ArrayExpression": ["Expression"],
+  "AssignmentExpression": ["Expression"],
+  "AwaitExpression": ["Expression"],
+  "BindFunctionExpression": ["Expression"],
+  "BindMemberExpression": ["Expression"],
+  "CallExpression": ["Expression"],
+  "ComprehensionExpression": ["Expression"],
+  "ConditionalExpression": ["Expression"],
+  "Identifier": ["Expression"],
+  "Literal": ["Expression"],
+  "MemberExpression": ["Expression"],
+  "NewExpression": ["Expression"],
+  "ObjectExpression": ["Expression"],
+  "SequenceExpression": ["Expression"],
+  "TaggedTemplateExpression": ["Expression"],
+  "ThisExpression": ["Expression"],
+  "UpdateExpression": ["Expression"],
+  "VirtualPropertyExpression": ["Expression"],
+  "XJSEmptyExpression": ["Expression"],
+  "XJSMemberExpression": ["Expression"],
+  "YieldExpression": ["Expression"]
 }

lib/6to5/types/index.js

@@ -66,14 +66,6 @@ _.each(t.FLIPPED_ALIAS_KEYS, function (types, type) {
 
 //
 
-t.isExpression = function (node) {
-  return !t.isStatement(node);
-};
-
-addAssert("Expression", t.isExpression);
-
-//
-
 t.isFalsyExpression = function (node) {
   if (t.isLiteral(node)) {
     return !node.value;
@@ -297,19 +289,26 @@ t.isVar = function (node) {
   return t.isVariableDeclaration(node, { kind: "var" }) && !node._let;
 };
 
+//
+
+t.COMMENT_KEYS = ["leadingComments", "trailingComments"];
+
 t.removeComments = function (child) {
-  delete child.leadingComments;
-  delete child.trailingComments;
+  _.each(t.COMMENT_KEYS, function (key) {
+    delete child[key];
+  });
   return child;
 };
 
 t.inheritsComments = function (child, parent) {
-  _.each(["leadingComments", "trailingComments"], function (key) {
+  _.each(t.COMMENT_KEYS, function (key) {
     child[key]  = _.uniq(_.compact([].concat(child[key], parent[key])));
   });
   return child;
 };
 
+//
+
 t.inherits = function (child, parent) {
   child.loc   = parent.loc;
   child.end   = parent.end;

package.json

@@ -1,7 +1,7 @@
 {
   "name": "6to5",
   "description": "Turn ES6 code into readable vanilla ES5 with source maps",
-  "version": "2.3.1",
+  "version": "2.4.0",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://github.com/6to5/6to5",
   "repository": {

test/fixtures/generation/comments/computed-property-comments-2/expected.js

@@ -3,8 +3,8 @@ var test = {
    * Before bracket init
    */
   ["a"]: "1",
-  [/*
-    * Inside bracket init
-    */
-  "b"]: "2"
+  [( /*
+      * Inside bracket init
+      */
+  "b")]: "2"
 }, ok = 42;

test/fixtures/generation/comments/computed-property-comments/expected.js

@@ -4,10 +4,10 @@ var test = {
    */
   ["a"]: "1",
 
-  [/*
-    * Inside bracket init
-    */
-  "b"]: "2",
+  [( /*
+      * Inside bracket init
+      */
+  "b")]: "2",
 
   ["c"
   /*
@@ -17,9 +17,9 @@ var test = {
   // Before bracket, line comment
   ["d"]: "4",
 
-  [
+  [(
   // Inside bracket, line comment
-  "e"]: "5",
+  "e")]: "5",
 
   ["f"
   // After bracket, line comment

test/fixtures/transformation/es6-classes/accessing-super-class/expected.js

@@ -13,29 +13,34 @@ var _inherits = function (child, parent) {
   if (parent) child.__proto__ = parent;
 };
 
-var Test = function Test() {
-  woops["super"].test();
-  Foo.call(this);
-  Foo.prototype.test.call(this);
-  foob(Foo);
+var Test = (function () {
+  var _TestSuper = Foo;
+  var Test = function Test() {
+    woops["super"].test();
+    _TestSuper.call(this);
+    _TestSuper.prototype.test.call(this);
+    foob(_TestSuper);
 
-  Foo.call.apply(Foo, [this].concat(_slice.call(arguments)));
-  Foo.call.apply(Foo, [this, "test"].concat(_slice.call(arguments)));
+    _TestSuper.call.apply(_TestSuper, [this].concat(_slice.call(arguments)));
+    _TestSuper.call.apply(_TestSuper, [this, "test"].concat(_slice.call(arguments)));
 
-  Foo.prototype.test.call.apply(Foo.prototype, [this].concat(_slice.call(arguments)));
-  Foo.prototype.test.call.apply(Foo.prototype, [this, "test"].concat(_slice.call(arguments)));
-};
+    _TestSuper.prototype.test.call.apply(_TestSuper.prototype, [this].concat(_slice.call(arguments)));
+    _TestSuper.prototype.test.call.apply(_TestSuper.prototype, [this, "test"].concat(_slice.call(arguments)));
+  };
 
-_inherits(Test, Foo);
+  _inherits(Test, _TestSuper);
 
-Test.prototype.test = function () {
-  Foo.prototype.test.call(this);
-  Foo.prototype.test.call.apply(Foo.prototype.test, [this].concat(_slice.call(arguments)));
-  Foo.prototype.test.call.apply(Foo.prototype.test, [this, "test"].concat(_slice.call(arguments)));
-};
+  Test.prototype.test = function () {
+    _TestSuper.prototype.test.call(this);
+    _TestSuper.prototype.test.call.apply(_TestSuper.prototype.test, [this].concat(_slice.call(arguments)));
+    _TestSuper.prototype.test.call.apply(_TestSuper.prototype.test, [this, "test"].concat(_slice.call(arguments)));
+  };
 
-Test.foo = function () {
-  Foo.foo.call(this);
-  Foo.foo.call.apply(Foo.foo, [this].concat(_slice.call(arguments)));
-  Foo.foo.call.apply(Foo.foo, [this, "test"].concat(_slice.call(arguments)));
-};
+  Test.foo = function () {
+    _TestSuper.foo.call(this);
+    _TestSuper.foo.call.apply(_TestSuper.foo, [this].concat(_slice.call(arguments)));
+    _TestSuper.foo.call.apply(_TestSuper.foo, [this, "test"].concat(_slice.call(arguments)));
+  };
+
+  return Test;
+})();

test/fixtures/transformation/es6-classes/accessing-super-properties/expected.js

@@ -12,9 +12,14 @@ var _inherits = function (child, parent) {
   if (parent) child.__proto__ = parent;
 };
 
-var Test = function Test() {
-  Foo.prototype.test;
-  Foo.prototype.test.whatever;
-};
+var Test = (function () {
+  var _TestSuper = Foo;
+  var Test = function Test() {
+    _TestSuper.prototype.test;
+    _TestSuper.prototype.test.whatever;
+  };
 
-_inherits(Test, Foo);
+  _inherits(Test, _TestSuper);
+
+  return Test;
+})();

test/fixtures/transformation/es6-classes/calling-super-properties/expected.js

@@ -12,13 +12,18 @@ var _inherits = function (child, parent) {
   if (parent) child.__proto__ = parent;
 };
 
-var Test = function Test() {
-  Foo.prototype.test.whatever();
-  Foo.prototype.test.call(this);
-};
+var Test = (function () {
+  var _TestSuper = Foo;
+  var Test = function Test() {
+    _TestSuper.prototype.test.whatever();
+    _TestSuper.prototype.test.call(this);
+  };
 
-_inherits(Test, Foo);
+  _inherits(Test, _TestSuper);
 
-Test.test = function () {
-  return Foo.wow.call(this);
-};
+  Test.test = function () {
+    return _TestSuper.wow.call(this);
+  };
+
+  return Test;
+})();

test/fixtures/transformation/es6-classes/constructor/expected.js

@@ -16,8 +16,13 @@ var Test = function Test() {
   this.state = "test";
 };
 
-var Foo = function Foo() {
-  this.state = "test";
-};
+var Foo = (function () {
+  var _FooSuper = Bar;
+  var Foo = function Foo() {
+    this.state = "test";
+  };
 
-_inherits(Foo, Bar);
+  _inherits(Foo, _FooSuper);
+
+  return Foo;
+})();

test/fixtures/transformation/es6-classes/super-class-id-member-expression/expected.js

@@ -12,18 +12,28 @@ var _inherits = function (child, parent) {
   if (parent) child.__proto__ = parent;
 };
 
-var BaseController = function BaseController() {
-  if (Chaplin.Controller) {
-    Chaplin.Controller.apply(this, arguments);
-  }
-};
+var BaseController = (function () {
+  var _BaseControllerSuper = Chaplin.Controller;
+  var BaseController = function BaseController() {
+    if (_BaseControllerSuper) {
+      _BaseControllerSuper.apply(this, arguments);
+    }
+  };
 
-_inherits(BaseController, Chaplin.Controller);
+  _inherits(BaseController, _BaseControllerSuper);
 
-var BaseController2 = function BaseController2() {
-  if (Chaplin.Controller.Another) {
-    Chaplin.Controller.Another.apply(this, arguments);
-  }
-};
+  return BaseController;
+})();
 
-_inherits(BaseController2, Chaplin.Controller.Another);
+var BaseController2 = (function () {
+  var _BaseController2Super = Chaplin.Controller.Another;
+  var BaseController2 = function BaseController2() {
+    if (_BaseController2Super) {
+      _BaseController2Super.apply(this, arguments);
+    }
+  };
+
+  _inherits(BaseController2, _BaseController2Super);
+
+  return BaseController2;
+})();

test/fixtures/transformation/es6-classes/super-class/expected.js

@@ -12,10 +12,15 @@ var _inherits = function (child, parent) {
   if (parent) child.__proto__ = parent;
 };
 
-var Test = function Test() {
-  if (Foo) {
-    Foo.apply(this, arguments);
-  }
-};
+var Test = (function () {
+  var _TestSuper = Foo;
+  var Test = function Test() {
+    if (_TestSuper) {
+      _TestSuper.apply(this, arguments);
+    }
+  };
 
-_inherits(Test, Foo);
+  _inherits(Test, _TestSuper);
+
+  return Test;
+})();

test/fixtures/transformation/es6-modules-amd/exports-default/expected.js

@@ -1,6 +1,6 @@
-define(["exports"], function (exports) {
-  "use strict";
+"use strict";
 
+define(["exports"], function (exports) {
   exports["default"] = foo;
   exports["default"] = 42;
   exports["default"] = {};

test/fixtures/transformation/es6-modules-amd/exports-from/expected.js

@@ -1,6 +1,6 @@
-define(["exports", "foo"], function (exports, _foo) {
-  "use strict";
+"use strict";
 
+define(["exports", "foo"], function (exports, _foo) {
   (function (obj) {
     for (var i in obj) {
       exports[i] = obj[i];

test/fixtures/transformation/es6-modules-amd/exports-named/expected.js

@@ -1,6 +1,6 @@
-define(["exports"], function (exports) {
-  "use strict";
+"use strict";
 
+define(["exports"], function (exports) {
   exports.foo = foo;
   exports.foo = foo;
   exports.bar = bar;

test/fixtures/transformation/es6-modules-amd/exports-variable/expected.js

@@ -1,6 +1,6 @@
-define(["exports"], function (exports) {
-  "use strict";
+"use strict";
 
+define(["exports"], function (exports) {
   exports.foo7 = foo7;
   var foo = exports.foo = 1;
   var foo = exports.foo = 1;

test/fixtures/transformation/es6-modules-amd/hoist-function-exports/expected.js

@@ -1,6 +1,6 @@
-define(["exports", "./evens"], function (exports, _evens) {
-  "use strict";
+"use strict";
 
+define(["exports", "./evens"], function (exports, _evens) {
   exports.nextOdd = nextOdd;
   var isEven = _evens.isEven;
   function nextOdd(n) {

test/fixtures/transformation/es6-modules-amd/imports-default/expected.js

@@ -1,6 +1,6 @@
-define(["exports", "foo"], function (exports, _foo) {
-  "use strict";
+"use strict";
 
+define(["exports", "foo"], function (exports, _foo) {
   var _interopRequire = function (obj) {
     return obj && (obj["default"] || obj);
   };

test/fixtures/transformation/es6-modules-amd/imports-glob/expected.js

@@ -1,5 +1,5 @@
-define(["exports", "foo"], function (exports, _foo) {
-  "use strict";
+"use strict";
 
+define(["exports", "foo"], function (exports, _foo) {
   var foo = _foo;
 });

test/fixtures/transformation/es6-modules-amd/imports-mixing/expected.js

@@ -1,6 +1,6 @@
-define(["exports", "foo"], function (exports, _foo) {
-  "use strict";
+"use strict";
 
+define(["exports", "foo"], function (exports, _foo) {
   var _interopRequire = function (obj) {
     return obj && (obj["default"] || obj);
   };

test/fixtures/transformation/es6-modules-amd/imports-named/expected.js

@@ -1,6 +1,6 @@
-define(["exports", "foo"], function (exports, _foo) {
-  "use strict";
+"use strict";
 
+define(["exports", "foo"], function (exports, _foo) {
   var bar = _foo.bar;
   var bar = _foo.bar;
   var baz = _foo.baz;

test/fixtures/transformation/es6-modules-amd/imports/expected.js

@@ -1,3 +1,3 @@
-define(["exports", "foo", "foo-bar", "./directory/foo-bar"], function (exports, _foo, _fooBar, _directoryFooBar) {
-  "use strict";
-});
+"use strict";
+
+define(["exports", "foo", "foo-bar", "./directory/foo-bar"], function (exports, _foo, _fooBar, _directoryFooBar) {});

test/fixtures/transformation/es6-modules-amd/module-name/expected.js

@@ -1,5 +1,5 @@
-define("es6-modules-amd/module-name/expected", ["exports"], function (exports) {
-  "use strict";
+"use strict";
 
+define("es6-modules-amd/module-name/expected", ["exports"], function (exports) {
   foobar();
 });

test/fixtures/transformation/es6-modules-amd/overview/expected.js

@@ -1,6 +1,6 @@
-define(["exports", "foo", "foo-bar", "./directory/foo-bar"], function (exports, _foo, _fooBar, _directoryFooBar) {
-  "use strict";
+"use strict";
 
+define(["exports", "foo", "foo-bar", "./directory/foo-bar"], function (exports, _foo, _fooBar, _directoryFooBar) {
   var _interopRequire = function (obj) {
     return obj && (obj["default"] || obj);
   };

test/fixtures/transformation/es6-modules-amd/remap/expected.js

@@ -1,6 +1,6 @@
-define(["exports"], function (exports) {
-  "use strict";
+"use strict";
 
+define(["exports"], function (exports) {
   var test = exports.test = 2;
   test = exports.test = 5;
   test = exports.test += 1;

test/fixtures/transformation/es6-modules-system/exports-default/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 System.register([], function (_export) {
   var Foo;
   _export("default", foo);
@@ -6,8 +8,6 @@ System.register([], function (_export) {
   return {
     setters: [],
     execute: function () {
-      "use strict";
-
       _export("default", 42);
 
       _export("default", {});

test/fixtures/transformation/es6-modules-system/exports-from/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 System.register(["foo"], function (_export) {
   return {
     setters: [function (_foo) {
@@ -19,8 +21,6 @@ System.register(["foo"], function (_export) {
 
       _export("bar", _foo.bar);
     }],
-    execute: function () {
-      "use strict";
-    }
+    execute: function () {}
   };
 });

test/fixtures/transformation/es6-modules-system/exports-named/expected.js

@@ -1,9 +1,9 @@
+"use strict";
+
 System.register([], function (_export) {
   return {
     setters: [],
     execute: function () {
-      "use strict";
-
       _export("foo", foo);
 
       _export("foo", foo);
@@ -19,4 +19,4 @@ System.register([], function (_export) {
       _export("bar", bar);
     }
   };
-});
+});

test/fixtures/transformation/es6-modules-system/exports-variable/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 System.register([], function (_export) {
   var foo, foo2, foo3, foo4, foo5, foo6, foo8;
   _export("foo7", foo7);
@@ -6,8 +8,6 @@ System.register([], function (_export) {
   return {
     setters: [],
     execute: function () {
-      "use strict";
-
       foo = _export("foo", 1);
       foo2 = _export("foo2", function () {});
       foo3 = _export("foo3", undefined);

test/fixtures/transformation/es6-modules-system/hoist-function-exports/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 System.register(["./evens"], function (_export) {
   var isEven, p, isOdd;
   _export("nextOdd", nextOdd);
@@ -11,8 +13,6 @@ System.register(["./evens"], function (_export) {
       isEven = _evens.isEven;
     }],
     execute: function () {
-      "use strict";
-
       p = _export("p", 5);
       isOdd = _export("isOdd", (function (isEven) {
         return function (n) {

test/fixtures/transformation/es6-modules-system/imports-default/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 System.register(["foo"], function (_export) {
   var foo, foo;
   return {
@@ -5,8 +7,6 @@ System.register(["foo"], function (_export) {
       foo = _foo["default"];
       foo = _foo["default"];
     }],
-    execute: function () {
-      "use strict";
-    }
+    execute: function () {}
   };
 });

test/fixtures/transformation/es6-modules-system/imports-glob/expected.js

@@ -1,11 +1,11 @@
+"use strict";
+
 System.register(["foo"], function (_export) {
   var foo;
   return {
     setters: [function (_foo) {
       foo = _foo;
     }],
-    execute: function () {
-      "use strict";
-    }
+    execute: function () {}
   };
 });

test/fixtures/transformation/es6-modules-system/imports-mixing/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 System.register(["foo"], function (_export) {
   var foo, xyz;
   return {
@@ -5,8 +7,6 @@ System.register(["foo"], function (_export) {
       foo = _foo["default"];
       xyz = _foo.baz;
     }],
-    execute: function () {
-      "use strict";
-    }
+    execute: function () {}
   };
 });

test/fixtures/transformation/es6-modules-system/imports-named/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 System.register(["foo"], function (_export) {
   var bar, bar, baz, baz, baz, xyz;
   return {
@@ -9,8 +11,6 @@ System.register(["foo"], function (_export) {
       baz = _foo.bar;
       xyz = _foo.xyz;
     }],
-    execute: function () {
-      "use strict";
-    }
+    execute: function () {}
   };
 });

test/fixtures/transformation/es6-modules-system/imports/expected.js

@@ -1,8 +1,8 @@
+"use strict";
+
 System.register(["foo", "foo-bar", "./directory/foo-bar"], function (_export) {
   return {
     setters: [function (_foo) {}, function (_fooBar) {}, function (_directoryFooBar) {}],
-    execute: function () {
-      "use strict";
-    }
+    execute: function () {}
   };
 });

test/fixtures/transformation/es6-modules-system/overview/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 System.register(["foo", "foo-bar", "./directory/foo-bar"], function (_export) {
   var foo, foo, bar, bar, test;
   return {
@@ -8,8 +10,6 @@ System.register(["foo", "foo-bar", "./directory/foo-bar"], function (_export) {
       bar = _foo.foo;
     }, function (_fooBar) {}, function (_directoryFooBar) {}],
     execute: function () {
-      "use strict";
-
       _export("test", test);
 
       test = _export("test", 5);

test/fixtures/transformation/es6-modules-system/remap/expected.js

@@ -1,10 +1,10 @@
+"use strict";
+
 System.register([], function (_export) {
   var test;
   return {
     setters: [],
     execute: function () {
-      "use strict";
-
       test = _export("test", 2);
       _export("test", test = 5);
       _export("test", test += 1);

test/fixtures/transformation/es6-modules-umd/exports-default/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports"], factory);
@@ -5,8 +7,6 @@
     factory(exports);
   }
 })(function (exports) {
-  "use strict";
-
   exports["default"] = foo;
   exports["default"] = 42;
   exports["default"] = {};

test/fixtures/transformation/es6-modules-umd/exports-from/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports", "foo"], factory);
@@ -5,8 +7,6 @@
     factory(exports, require("foo"));
   }
 })(function (exports, _foo) {
-  "use strict";
-
   (function (obj) {
     for (var i in obj) {
       exports[i] = obj[i];

test/fixtures/transformation/es6-modules-umd/exports-named/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports"], factory);
@@ -5,8 +7,6 @@
     factory(exports);
   }
 })(function (exports) {
-  "use strict";
-
   exports.foo = foo;
   exports.foo = foo;
   exports.bar = bar;

test/fixtures/transformation/es6-modules-umd/exports-variable/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports"], factory);
@@ -5,8 +7,6 @@
     factory(exports);
   }
 })(function (exports) {
-  "use strict";
-
   exports.foo7 = foo7;
   var foo = exports.foo = 1;
   var foo = exports.foo = 1;

test/fixtures/transformation/es6-modules-umd/hoist-function-exports/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports", "./evens"], factory);
@@ -5,8 +7,6 @@
     factory(exports, require("./evens"));
   }
 })(function (exports, _evens) {
-  "use strict";
-
   exports.nextOdd = nextOdd;
   var isEven = _evens.isEven;
   function nextOdd(n) {

test/fixtures/transformation/es6-modules-umd/imports-default/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports", "foo"], factory);
@@ -5,8 +7,6 @@
     factory(exports, require("foo"));
   }
 })(function (exports, _foo) {
-  "use strict";
-
   var _interopRequire = function (obj) {
     return obj && (obj["default"] || obj);
   };

test/fixtures/transformation/es6-modules-umd/imports-glob/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports", "foo"], factory);
@@ -5,7 +7,5 @@
     factory(exports, require("foo"));
   }
 })(function (exports, _foo) {
-  "use strict";
-
   var foo = _foo;
 });

test/fixtures/transformation/es6-modules-umd/imports-mixing/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports", "foo"], factory);
@@ -5,8 +7,6 @@
     factory(exports, require("foo"));
   }
 })(function (exports, _foo) {
-  "use strict";
-
   var _interopRequire = function (obj) {
     return obj && (obj["default"] || obj);
   };

test/fixtures/transformation/es6-modules-umd/imports-named/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports", "foo"], factory);
@@ -5,8 +7,6 @@
     factory(exports, require("foo"));
   }
 })(function (exports, _foo) {
-  "use strict";
-
   var bar = _foo.bar;
   var bar = _foo.bar;
   var baz = _foo.baz;

test/fixtures/transformation/es6-modules-umd/imports/expected.js

@@ -1,9 +1,9 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports", "foo", "foo-bar", "./directory/foo-bar"], factory);
   } else if (typeof exports !== "undefined") {
     factory(exports, require("foo"), require("foo-bar"), require("./directory/foo-bar"));
   }
-})(function (exports, _foo, _fooBar, _directoryFooBar) {
-  "use strict";
-});
+})(function (exports, _foo, _fooBar, _directoryFooBar) {});

test/fixtures/transformation/es6-modules-umd/module-name/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define("es6-modules-umd/module-name/expected", ["exports"], factory);
@@ -5,7 +7,5 @@
     factory(exports);
   }
 })(function (exports) {
-  "use strict";
-
   foobar();
 });

test/fixtures/transformation/es6-modules-umd/overview/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports", "foo", "foo-bar", "./directory/foo-bar"], factory);
@@ -5,8 +7,6 @@
     factory(exports, require("foo"), require("foo-bar"), require("./directory/foo-bar"));
   }
 })(function (exports, _foo, _fooBar, _directoryFooBar) {
-  "use strict";
-
   var _interopRequire = function (obj) {
     return obj && (obj["default"] || obj);
   };

test/fixtures/transformation/es6-modules-umd/remap/expected.js

@@ -1,3 +1,5 @@
+"use strict";
+
 (function (factory) {
   if (typeof define === "function" && define.amd) {
     define(["exports"], factory);
@@ -5,8 +7,6 @@
     factory(exports);
   }
 })(function (exports) {
-  "use strict";
-
   var test = exports.test = 2;
   test = exports.test = 5;
   test = exports.test += 1;

test/fixtures/transformation/es7-array-comprehension/arguments/expected.js

@@ -2,9 +2,16 @@
 
 function add() {
   var _arguments = arguments;
-  return [1, 2, 3].map(function (i) {
-    return i * _arguments[0];
-  });
+  return (function () {
+    var _arr = [];
+
+    for (var _iterator = [1, 2, 3][Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
+      var i = _step.value;
+      _arr.push(i * _arguments[0]);
+    }
+
+    return _arr;
+  })();
 }
 
 add(5);

test/fixtures/transformation/es7-array-comprehension/array-expression-single-if/expected.js

@@ -1,7 +1,14 @@
 "use strict";
 
-var arr = [1, 2, 3].filter(function (i) {
-  return i > 1;
-}).map(function (i) {
-  return i * i;
-});
+var arr = (function () {
+  var _arr = [];
+
+  for (var _iterator = [1, 2, 3][Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
+    var i = _step.value;
+    if (i > 1) {
+      _arr.push(i * i);
+    }
+  }
+
+  return _arr;
+})();

test/fixtures/transformation/es7-array-comprehension/array-expression-single/expected.js

@@ -1,5 +1,12 @@
 "use strict";
 
-var arr = [1, 2, 3].map(function (i) {
-  return i * i;
-});
+var arr = (function () {
+  var _arr = [];
+
+  for (var _iterator = [1, 2, 3][Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
+    var i = _step.value;
+    _arr.push(i * i);
+  }
+
+  return _arr;
+})();

test/fixtures/transformation/es7-array-comprehension/single-if/expected.js

@@ -1,11 +1,14 @@
 "use strict";
 
-var _toArray = function (arr) {
-  return Array.isArray(arr) ? arr : Array.from(arr);
-};
+var arr = (function () {
+  var _arr = [];
 
-var arr = _toArray(nums).filter(function (i) {
-  return i > 1;
-}).map(function (i) {
-  return i * i;
-});
+  for (var _iterator = nums[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
+    var i = _step.value;
+    if (i > 1) {
+      _arr.push(i * i);
+    }
+  }
+
+  return _arr;
+})();

test/fixtures/transformation/es7-array-comprehension/single/expected.js

@@ -1,9 +1,12 @@
 "use strict";
 
-var _toArray = function (arr) {
-  return Array.isArray(arr) ? arr : Array.from(arr);
-};
+var arr = (function () {
+  var _arr = [];
 
-var arr = _toArray(nums).map(function (i) {
-  return i * i;
-});
+  for (var _iterator = nums[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
+    var i = _step.value;
+    _arr.push(i * i);
+  }
+
+  return _arr;
+})();

test/fixtures/transformation/es7-array-comprehension/this/expected.js

@@ -2,9 +2,16 @@
 
 function add() {
   var _this = this;
-  return [1, 2, 3].map(function (i) {
-    return i * _this.multiplier;
-  });
+  return (function () {
+    var _arr = [];
+
+    for (var _iterator = [1, 2, 3][Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
+      var i = _step.value;
+      _arr.push(i * _this.multiplier);
+    }
+
+    return _arr;
+  })();
 }
 
 add.call({ multiplier: 5 });

test/fixtures/transformation/optional-async-to-generator/basic/actual.js

@@ -0,0 +1,3 @@
+var foo = async function () {
+  var wat = await bar();
+};

test/fixtures/transformation/optional-async-to-generator/basic/expected.js

@@ -0,0 +1,42 @@
+"use strict";
+
+var _asyncToGenerator = function (fn) {
+  return function () {
+    var gen = fn.apply(this, arguments);
+
+    return new Promise(function (resolve, reject) {
+      function step(getNext) {
+        var next;
+        try {
+          next = getNext();
+        } catch (e) {
+          reject(e);
+
+          return;
+        }
+        if (next.done) {
+          resolve(next.value);
+
+          return;
+        }
+        Promise.resolve(next.value).then(function (v) {
+          step(function () {
+            return gen.next(v);
+          });
+        }, function (e) {
+          step(function () {
+            return gen["throw"](e);
+          });
+        });
+      }
+
+      step(function () {
+        return gen.next();
+      });
+    });
+  };
+};
+
+var foo = _asyncToGenerator(function* () {
+  var wat = yield bar();
+});

test/fixtures/transformation/optional-async-to-generator/options.json

@@ -0,0 +1,3 @@
+{
+  "optional": ["asyncToGenerator"]
+}

test/fixtures/transformation/optional-bluebird-coroutines/basic/actual.js

@@ -0,0 +1,3 @@
+var foo = async function () {
+  var wat = await bar();
+};

test/fixtures/transformation/optional-bluebird-coroutines/basic/expected.js

@@ -0,0 +1,11 @@
+"use strict";
+
+var _interopRequire = function (obj) {
+  return obj && (obj["default"] || obj);
+};
+
+var Bluebird = _interopRequire(require("bluebird"));
+
+var foo = Bluebird.coroutine(function* () {
+  var wat = yield bar();
+});

test/fixtures/transformation/optional-bluebird-coroutines/options.json

@@ -0,0 +1,3 @@
+{
+  "optional": ["bluebirdCoroutines"]
+}

test/fixtures/transformation/optional-core-aliasing/es7-array-comprehensions/expected.js

@@ -1,15 +1,18 @@
 "use strict";
 
-var _toArray = function (arr) {
-  return Array.isArray(arr) ? arr : _core.Array.from(arr);
-};
-
 var _interopRequire = function (obj) {
   return obj && (obj["default"] || obj);
 };
 
 var _core = _interopRequire(require("core-js/library"));
 
-var arr = _toArray(nums).map(function (i) {
-  return i * i;
-});
+var arr = (function () {
+  var _arr = [];
+
+  for (var _iterator = _core.$for.getIterator(nums), _step; !(_step = _iterator.next()).done;) {
+    var i = _step.value;
+    _arr.push(i * i);
+  }
+
+  return _arr;
+})();