v2.4.3

Extend the license to the new year

CHANGELOG.md

@@ -2,6 +2,40 @@
 
 Gaps between patch versions are faulty/broken releases.
 
+## 2.4.3
+
+ * Upgrade `acorn-6to5`.
+ * Add support for `FunctionDeclaration`s in `bluebirdCoroutines` and `asyncToGenerators` transformers.
+
+## 2.4.2
+
+ * Upgrade `acorn-6to5`.
+ * Better uids generated for various transformers based on parent node.
+ * Alias flat references in `coreAliasing` transformer.
+
+## 2.4.1
+
+ * Better whitespace handling of parenthesized expressions due to trailing comments.
+ * Fix `yield` inside of comprehensions.
+
+## 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.
+ * Use `Object.defineProperty` for computed properties.
+
 ## 2.3.0
 
  * Upgrade `acorn-6to5`.

LICENSE

@@ -1,4 +1,4 @@
-Copyright (c) 2014 Sebastian McKenzie
+Copyright (c) 2014-2015 Sebastian McKenzie
 
 MIT License
 

README.md

@@ -11,10 +11,6 @@
     <img alt="Travis Status" src="http://img.shields.io/travis/6to5/6to5/master.svg?style=flat&amp;label=travis">
   </a>
 
-  <a href="https://ci.appveyor.com/project/sebmck/6to5">
-    <img alt="Appveyor Status" src="http://img.shields.io/appveyor/ci/sebmck/6to5.svg?style=flat&amp;label=appveyor">
-  </a>
-
   <a href="https://codeclimate.com/github/6to5/6to5">
     <img alt="Code Climate Score" src="http://img.shields.io/codeclimate/github/6to5/6to5.svg?style=flat">
   </a>

doc/playground.md

@@ -90,23 +90,27 @@ equivalent to
 ```javascript
 var foo = {
   get bar() {
-    if (this._barRan) return this._bar;
-    this._barRan = true;
-    return this._bar = complex();
+    return Object.defineProperty(this, "bar", {
+      value: complex(),
+      enumerable: true,
+      configurable: true,
+      writable: true
+    }).bar;
   }
 };
 
 class Foo {
   get bar() {
-    if (this._barRan) return this._bar;
-    this._barRan = true;
-    return this._bar = complex();
+    return Object.defineProperty(this, "bar", {
+      value: complex(),
+      enumerable: true,
+      configurable: true,
+      writable: true
+    }).bar;
   }
 }
 ```
 
-**NOTE:** Memoised functions will return the result of the **first** execution, regardless of arguments.
-
 ### This shorthand
 
 ```javascript

lib/6to5/file.js

@@ -10,10 +10,11 @@ var t         = require("./types");
 var _         = require("lodash");
 
 function File(opts) {
-  this.opts         = File.normaliseOptions(opts);
-  this.transformers = this.getTransformers();
-  this.uids         = {};
-  this.ast          = {};
+  this.dynamicImports = [];
+  this.opts           = File.normaliseOptions(opts);
+  this.transformers   = this.getTransformers();
+  this.uids           = {};
+  this.ast            = {};
 }
 
 File.declarations = [
@@ -26,7 +27,13 @@ File.declarations = [
   "sliced-to-array",
   "object-without-properties",
   "has-own",
-  "slice"
+  "slice",
+  "define-property",
+  "async-to-generator"
+];
+
+File.excludeDeclarationsFromRuntime = [
+  "async-to-generator"
 ];
 
 File.normaliseOptions = function (opts) {
@@ -94,6 +101,10 @@ File.prototype.getTransformers = function () {
   _.each(transform.transformers, function (transformer) {
     if (transformer.canRun(file)) {
       transformers.push(transformer);
+
+      if (transformer.manipulateOptions) {
+        transformer.manipulateOptions(file.opts, file);
+      }
     }
   });
 
@@ -143,6 +154,13 @@ 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));
+  declar._blockHoist = 3;
+  this.dynamicImports.push(declar);
+};
+
 File.prototype.addDeclaration = function (name) {
   if (!_.contains(File.declarations, name)) {
     throw new ReferenceError("unknown declaration " + name);
@@ -155,7 +173,7 @@ 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 +148,12 @@ CodeGenerator.prototype.print = function (node, parent, opts) {
   };
 
   if (this[node.type]) {
+    var needsCommentParens = t.isExpression(node) && node.leadingComments && node.leadingComments.length;
+    var needsParens        = needsCommentParens || n.needsParens(node, parent);
+
+    if (needsParens) this.push("(");
+    if (needsCommentParens) this.indent();
+
     this.printLeadingComments(node, parent);
 
     newline(true);
@@ -155,13 +161,12 @@ 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 (needsCommentParens) {
+      this.newline();
+      this.dedent();
+    }
     if (needsParens) this.push(")");
 
     this.map.mark(node, "end");

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

@@ -55,6 +55,8 @@ _.each({
   Function: 1,
   Class: 1,
   For: 1,
+  ArrayExpression: { after: 1 },
+  ObjectExpression: { after: 1 },
   SwitchStatement: 1,
   IfStatement: { before: 1 },
   CallExpression: { after: 1 },

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/modules/_default.js

@@ -126,7 +126,7 @@ DefaultFormatter.prototype._pushStatement = function (ref, nodes) {
 
 DefaultFormatter.prototype._hoistExport = function (declar, assign, priority) {
   if (t.isFunctionDeclaration(declar)) {
-    assign._blockHoist = priority || 1;
+    assign._blockHoist = priority || 2;
   }
 
   return assign;

lib/6to5/transformation/modules/common.js

@@ -57,6 +57,7 @@ CommonJSFormatter.prototype.importDeclaration = function (node, nodes) {
 CommonJSFormatter.prototype.exportDeclaration = function (node, nodes) {
   if (node.default) {
     var declar = node.declaration;
+    var assign;
 
     // module.exports = VALUE;
     var templateName = "exports-default-module";
@@ -64,15 +65,29 @@ CommonJSFormatter.prototype.exportDeclaration = function (node, nodes) {
     // exports = module.exports = VALUE;
     if (this.hasNonDefaultExports) templateName = "exports-default-module-override";
 
-    var assign = util.template(templateName, {
-      VALUE: this._pushStatement(declar, nodes)
-    }, true);
+    if (t.isFunction(declar) || !this.hasNonDefaultExports) {
+      assign = util.template(templateName, {
+        VALUE: this._pushStatement(declar, nodes)
+      }, true);
 
-    // hoist to the top if this default is a function
-    nodes.push(this._hoistExport(declar, assign, 2));
-  } else {
-    DefaultFormatter.prototype.exportDeclaration.apply(this, arguments);
+      // hoist to the top if this default is a function
+      nodes.push(this._hoistExport(declar, assign, 3));
+      return;
+    } else {
+      // this export isn't a function so we can't hoist it to the top so we need to set it
+      // at the very end of the file with something like:
+      //
+      //   module.exports = Object.assign(exports["default"], exports)
+      //
+
+      assign = util.template("common-export-default-assign", true);
+      assign._blockHoist = 0;
+
+      nodes.push(assign);
+    }
   }
+
+  DefaultFormatter.prototype.exportDeclaration.apply(this, arguments);
 };
 
 CommonJSFormatter.prototype.exportSpecifier = function (specifier, node, nodes) {

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/templates/common-export-default-assign.js

@@ -0,0 +1 @@
+module.exports = Object.assign(exports["default"], exports);

lib/6to5/transformation/templates/define-property.js

@@ -0,0 +1,8 @@
+(function (obj, key, value) {
+  return Object.defineProperty(obj, key, {
+    value: value,
+    enumerable: true,
+    configurable: true,
+    writable: true
+  });
+});

lib/6to5/transformation/templates/function-return-obj.js

@@ -1,3 +0,0 @@
-(function (KEY) {
-  return KEY;
-})(OBJECT)

lib/6to5/transformation/templates/object-define-properties-closure.js

@@ -1,4 +0,0 @@
-(function (KEY) {
-  CONTENT;
-  return KEY;
-})(OBJECT);

lib/6to5/transformation/templates/object-getter-memoization.js

@@ -1,6 +0,0 @@
-Object.defineProperty(this, KEY, {
-  enumerable: true,
-  configurable: true,
-  writable: true,
-  value: VALUE
-})

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"),
@@ -81,11 +84,12 @@ _.each({
   _declarations:             require("./transformers/_declarations"),
 
   coreAliasing:              require("./transformers/optional-core-aliasing"),
+  undefinedToVoid:           require("./transformers/optional-undefined-to-void"),
 
   // 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/_block-hoist.js

@@ -1,17 +1,27 @@
 var _ = require("lodash");
 
+// Priority:
+//
+//  - 0 We want this to be at the **very** bottom
+//  - 1 Default node position
+//  - 2 Priority over normal nodes
+//  - 3 We want this to be at the **very** top
+
 exports.BlockStatement =
 exports.Program = {
   exit: function (node) {
     var hasChange = false;
     for (var i in node.body) {
       var bodyNode = node.body[i];
-      if (bodyNode && bodyNode._blockHoist) hasChange = true;
+      if (bodyNode && bodyNode._blockHoist != null) hasChange = true;
     }
     if (!hasChange) return;
 
     var nodePriorities = _.groupBy(node.body, function (bodyNode) {
-      return bodyNode._blockHoist || 0;
+      var priority = bodyNode._blockHoist;
+      if (priority == null) priority = 1;
+      if (priority === true) priority = 2;
+      return priority;
     });
 
     node.body = _.flatten(_.values(nodePriorities).reverse());

lib/6to5/transformation/transformers/es5-property-method-assignment.js

@@ -1,4 +1,5 @@
 var util = require("../../util");
+var t    = require("../../types");
 
 exports.Property = function (node) {
   if (node.method) node.method = false;
@@ -20,14 +21,21 @@ exports.ObjectExpression = function (node, parent, file) {
 
   if (!hasAny) return;
 
-  var objId = util.getUid(parent, file);
+  if (node.properties.length) {
+    var objId = t.getUid(parent, file);
 
-  return util.template("object-define-properties-closure", {
-    KEY: objId,
-    OBJECT: node,
-    CONTENT: util.template("object-define-properties", {
-      OBJECT: objId,
+    return util.template("object-define-properties-closure", {
+      KEY: objId,
+      OBJECT: node,
+      CONTENT: util.template("object-define-properties", {
+        OBJECT: objId,
+        PROPS:  util.buildDefineProperties(mutatorMap)
+      })
+    });
+  } else {
+    return util.template("object-define-properties", {
+      OBJECT: node,
       PROPS:  util.buildDefineProperties(mutatorMap)
-    })
-  });
+    });
+  }
 };

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)
       ]);
@@ -85,23 +85,17 @@ Class.prototype.run = function () {
 
   //
 
-  if (superName && t.isDynamic(superName)) {
-    // so we're only evaluating it once
-    var superRefName = "super";
-    if (className) superRefName = className.name + "Super";
+  if (superName) {
+    this.closure = true;
 
-    var superRef = file.generateUidIdentifier(superRefName, this.scope);
+    // so we're only evaluating it once
+    var superRef = t.getUid(superName, this.file);
     body.unshift(t.variableDeclaration("var", [
       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/es6-computed-property-names.js

@@ -1,47 +1,96 @@
-var util = require("../../util");
-var t    = require("../../types");
+var t = require("../../types");
 
 exports.ObjectExpression = function (node, parent, file) {
   var hasComputed = false;
+  var prop;
+  var key;
+  var i;
 
-  var computed = [];
-
-  node.properties = node.properties.filter(function (prop) {
-    if (prop.computed) {
-      hasComputed = true;
-      computed.unshift(prop);
-      return false;
-    } else {
-      return true;
-    }
-  });
+  for (i in node.properties) {
+    hasComputed = t.isProperty(node.properties[i], { computed: true });
+    if (hasComputed) break;
+  }
 
   if (!hasComputed) return;
 
-  var objId = util.getUid(parent, file);
+  var objId = t.getUid(parent, file);
 
-  var container = util.template("function-return-obj", {
-    KEY: objId,
-    OBJECT: node
-  });
+  var body = [];
+  var container = t.functionExpression(null, [], t.blockStatement(body));
+  container._aliasFunction = true;
 
-  var containerCallee = container.callee;
-  var containerBody = containerCallee.body.body;
+  var props = node.properties;
 
-  containerCallee._aliasFunction = true;
+  // normalise key
 
-  for (var i in computed) {
-    var prop = computed[i];
-    containerBody.unshift(
-      t.expressionStatement(
-        t.assignmentExpression(
-          "=",
-          t.memberExpression(objId, prop.key, true),
-          prop.value
-        )
-      )
-    );
+  for (i in props) {
+    prop = props[i];
+    key = prop.key;
+
+    if (!prop.computed && t.isIdentifier(key)) {
+      prop.key = t.literal(key.name);
+    }
   }
 
-  return container;
+  // add all non-computed properties and `__proto__` properties to the initializer
+
+  var initProps = [];
+  var broken = false;
+
+  for (i in props) {
+    prop = props[i];
+
+    if (prop.computed) {
+      broken = true;
+    }
+
+    if (!broken || t.isLiteral(prop.key, { value: "__proto__" })) {
+      initProps.push(prop);
+      props[i] = null;
+    }
+  }
+
+  // add a simple assignment for all Symbol member expressions due to symbol polyfill limitations
+  // otherwise use Object.defineProperty
+
+  for (i in props) {
+    prop = props[i];
+    if (!prop) continue;
+
+    key = prop.key;
+    var bodyNode;
+
+    if (prop.computed && t.isMemberExpression(key) && t.isIdentifier(key.object, { name: "Symbol" })) {
+      bodyNode = t.assignmentExpression(
+        "=",
+        t.memberExpression(objId, key, true),
+        prop.value
+      );
+    } else {
+      bodyNode = t.callExpression(file.addDeclaration("define-property"), [objId, key, prop.value]);
+    }
+
+    body.push(t.expressionStatement(bodyNode));
+  }
+
+  // only one node and it's a Object.defineProperty that returns the object
+
+  if (body.length === 1) {
+    var first = body[0].expression;
+
+    if (t.isCallExpression(first)) {
+      first.arguments[0] = t.objectExpression([]);
+      return first;
+    }
+  }
+
+  //
+
+  body.unshift(t.variableDeclaration("var", [
+    t.variableDeclarator(objId, t.objectExpression(initProps))
+  ]));
+
+  body.push(t.returnStatement(objId));
+
+  return t.callExpression(container, []);
 };

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

@@ -75,7 +75,7 @@ var pushArrayPattern = function (opts, nodes, pattern, parentId) {
 
   var toArray = opts.file.toArray(parentId, !hasSpreadElement && pattern.elements.length);
 
-  var _parentId = opts.file.generateUidIdentifier("ref", opts.scope);
+  var _parentId = t.getUid(parentId, opts.file, opts.scope);
   nodes.push(t.variableDeclaration("var", [
     t.variableDeclarator(_parentId, toArray)
   ]));
@@ -113,7 +113,7 @@ var pushPattern = function (opts) {
   var scope = opts.scope;
 
   if (!t.isMemberExpression(parentId) && !t.isIdentifier(parentId)) {
-    var key = file.generateUidIdentifier("ref", scope);
+    var key = t.getUid(parentId, file, scope);
 
     nodes.push(t.variableDeclaration("var", [
       t.variableDeclarator(key, parentId)

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

@@ -1,5 +1,11 @@
 var t = require("../../types");
 
+exports.ast = {
+  before: function (ast, file) {
+    ast.program.body = file.dynamicImports.concat(ast.program.body);
+  }
+};
+
 exports.ImportDeclaration = function (node, parent, file) {
   var nodes = [];
 
@@ -11,6 +17,12 @@ exports.ImportDeclaration = function (node, parent, file) {
     file.moduleFormatter.importDeclaration(node, nodes, parent);
   }
 
+  if (nodes.length === 1) {
+    // inherit `_blockHoist`
+    // this for `_blockHoist` in File.prototype.addImport
+    nodes[0]._blockHoist = node._blockHoist;
+  }
+
   return nodes;
 };
 

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 uid = file.generateUidIdentifier("arr");
+var build = function (node, parent, file, scope) {
+  var uid = t.getUid(parent, file, scope);
 
   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.callee.generator = true;
+    container = t.yieldExpression(container, true);
+  }
+
   var returnStatement = body.pop();
 
   body.push(exports._build(node, function () {
@@ -73,12 +55,8 @@ exports._build = function (node, buildBody) {
   );
 };
 
-exports.ComprehensionExpression = function (node, parent, file) {
+exports.ComprehensionExpression = function (node, parent, file, scope) {
   if (node.generator) return;
 
-  if (node.blocks.length === 1) {
-    return single(node, file);
-  } else {
-    return multiple(node, file);
-  }
+  return build(node, parent, file, scope);
 };

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

@@ -0,0 +1,11 @@
+var bluebirdCoroutines = require("./optional-bluebird-coroutines");
+
+exports.optional = true;
+
+exports.manipulateOptions = bluebirdCoroutines.manipulateOptions;
+
+exports.Function = function (node, parent, file) {
+  if (!node.async || node.generator) return;
+
+  return bluebirdCoroutines._Function(node, file.addDeclaration("async-to-generator"));
+};

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

@@ -0,0 +1,45 @@
+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, callId) {
+  node.async = false;
+  node.generator = true;
+
+  traverse(node, {
+    enter: function (node) {
+      if (t.isFunction(node)) this.stop();
+
+      if (t.isAwaitExpression(node)) {
+        node.type = "YieldExpression";
+      }
+    }
+  });
+
+  var call = t.callExpression(callId, [node]);
+
+  if (t.isFunctionDeclaration(node)) {
+    var declar = t.variableDeclaration("var", [
+      t.variableDeclarator(node.id, call)
+    ]);
+    declar._blockHoist = true;
+    return declar;
+  } else {
+    return call;
+  }
+};
+
+exports.Function = function (node, parent, file) {
+  if (!node.async || node.generator) return;
+
+  var id = t.identifier("Bluebird");
+  file.addImport(id, "bluebird");
+
+  return exports._Function(node, t.memberExpression(id, t.identifier("coroutine")));
+};

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

@@ -4,14 +4,16 @@ var core     = require("core-js/library");
 var t        = require("../../types");
 var _        = require("lodash");
 
+var coreHas = function (node) {
+  return node.name !== "_" && _.has(core, node.name);
+};
+
 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) {
@@ -26,11 +28,13 @@ exports.ast = {
 
           if (!t.isReferenced(obj, node)) return;
 
-          var coreHasObject = obj.name !== "_" && _.has(core, obj.name);
-          if (coreHasObject && _.has(core[obj.name], prop.name)) {
+          if (coreHas(obj) && _.has(core[obj.name], prop.name)) {
             this.stop();
             return t.memberExpression(file._coreId, node);
           }
+        } else if (t.isIdentifier(node) && !t.isMemberExpression(parent) && t.isReferenced(node, parent) && coreHas(node)) {
+          // new Promise -> new _core.Promise
+          return t.memberExpression(file._coreId, node);
         } else if (t.isCallExpression(node)) {
           // arr[Symbol.iterator]() -> _core.$for.getIterator(arr)
 

lib/6to5/transformation/transformers/optional-undefined-to-void.js

@@ -0,0 +1,9 @@
+var t = require("../../types");
+
+exports.optional = true;
+
+exports.Identifier = function (node, parent) {
+  if (node.name === "undefined" && t.isReferenced(node, parent)) {
+    return t.unaryExpression("void", t.literal(0), true);
+  }
+};

lib/6to5/transformation/transformers/playground-memoization-operator.js

@@ -10,7 +10,7 @@ var getPropRef = function (nodes, prop, file, scope) {
   if (t.isIdentifier(prop)) {
     return t.literal(prop.name);
   } else {
-    var temp = file.generateUidIdentifier("propKey", scope);
+    var temp = t.getUid(prop, file, scope);
     nodes.push(t.variableDeclaration("var", [
       t.variableDeclarator(temp, prop)
     ]));
@@ -20,7 +20,7 @@ var getPropRef = function (nodes, prop, file, scope) {
 
 var getObjRef = function (nodes, obj, file, scope) {
   if (t.isDynamic(obj)) {
-    var temp = file.generateUidIdentifier("obj", scope);
+    var temp = t.getUid(obj, file, scope);
     nodes.push(t.variableDeclaration("var", [
       t.variableDeclarator(temp, obj)
     ]));

lib/6to5/transformation/transformers/playground-object-getter-memoization.js

@@ -1,9 +1,8 @@
 var traverse = require("../../traverse");
-var util     = require("../../util");
 var t        = require("../../types");
 
 exports.Property =
-exports.MethodDefinition = function (node) {
+exports.MethodDefinition = function (node, parent, file) {
   if (node.kind !== "memo") return;
   node.kind = "get";
 
@@ -21,10 +20,11 @@ exports.MethodDefinition = function (node) {
       if (t.isFunction(node)) return;
 
       if (t.isReturnStatement(node) && node.argument) {
-        node.argument = t.memberExpression(util.template("object-getter-memoization", {
-          KEY: key,
-          VALUE: node.argument
-        }), key, true);
+        node.argument = t.memberExpression(t.callExpression(file.addDeclaration("define-property"), [
+          t.thisExpression(),
+          key,
+          node.argument
+        ]), key, true);
       }
     }
   });

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;
@@ -164,7 +156,7 @@ t.toIdentifier = function (name) {
   if (t.isIdentifier(name)) return name.name;
 
   // replace all non-valid identifiers with dashes
-  name = name.replace(/[^a-zA-Z0-9]/g, "-");
+  name = name.replace(/[^a-zA-Z0-9$_]/g, "-");
 
   // remove all dashes and numbers from start of name
   name = name.replace(/^[-0-9]+/, "");
@@ -174,6 +166,9 @@ t.toIdentifier = function (name) {
     return c ? c.toUpperCase() : "";
   });
 
+  // remove underscores from start of name
+  name = name.replace(/^\_/, "");
+
   return name || '_';
 };
 
@@ -239,6 +234,49 @@ t.toBlock = function (node, parent) {
   return t.blockStatement(node);
 };
 
+t.getUid = function (parent, file, scope) {
+  var node = parent;
+
+  if (t.isAssignmentExpression(parent)) {
+    node = parent.left;
+  } else if (t.isVariableDeclarator(parent)) {
+    node = parent.id;
+  }
+
+  var id = "ref";
+
+  if (t.isProperty(node)) {
+    node = node.key;
+  }
+
+  if (t.isIdentifier(node)) {
+    id = node.name;
+  } else if (t.isLiteral(node)) {
+    id = node.value;
+  } else if (t.isMemberExpression(node)) {
+    var parts = [];
+
+    var add = function (node) {
+      if (t.isMemberExpression(node)) {
+        add(node.object);
+        add(node.property);
+      } else if (t.isIdentifier(node)) {
+        parts.push(node.name);
+      } else if (t.isLiteral(node)) {
+        parts.push(node.value);
+      }
+    };
+
+    add(node);
+
+    id = parts.join("$");
+  }
+
+  id = id.replace(/^_/, "");
+
+  return file.generateUidIdentifier(id, scope);
+};
+
 t.getIds = function (node, map, ignoreTypes) {
   ignoreTypes = ignoreTypes || [];
 
@@ -297,19 +335,26 @@ 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;

lib/6to5/util.js

@@ -52,22 +52,6 @@ exports.arrayify = function (val) {
   throw new TypeError("illegal type for arrayify");
 };
 
-exports.getUid = function (parent, file) {
-  var node;
-
-  if (t.isAssignmentExpression(parent)) {
-    node = parent.left;
-  } else if (t.isVariableDeclarator(parent)) {
-    node = parent.id;
-  }
-
-  var id = "ref";
-
-  if (t.isIdentifier(node)) id = node.name;
-
-  return file.generateUidIdentifier(id);
-};
-
 exports.isAbsolute = function (loc) {
   if (!loc) return false;
   if (loc[0] === "/") return true; // unix

package.json

@@ -1,7 +1,7 @@
 {
   "name": "6to5",
   "description": "Turn ES6 code into readable vanilla ES5 with source maps",
-  "version": "2.3.0",
+  "version": "2.4.3",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://github.com/6to5/6to5",
   "repository": {
@@ -35,7 +35,7 @@
     "test": "make test"
   },
   "dependencies": {
-    "acorn-6to5": "0.11.1-1",
+    "acorn-6to5": "0.11.1-3",
     "ast-types": "~0.6.1",
     "chokidar": "0.11.1",
     "commander": "2.5.0",

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

@@ -3,8 +3,9 @@ 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 +4,11 @@ var test = {
    */
   ["a"]: "1",
 
-  [/*
-    * Inside bracket init
-    */
-  "b"]: "2",
+  [( /*
+      * Inside bracket init
+      */
+    "b"
+  )]: "2",
 
   ["c"
   /*
@@ -17,9 +18,10 @@ var test = {
   // Before bracket, line comment
   ["d"]: "4",
 
-  [
-  // Inside bracket, line comment
-  "e"]: "5",
+  [(
+    // Inside bracket, line comment
+    "e"
+  )]: "5",
 
   ["f"
   // After bracket, line comment

test/fixtures/transformation/es5-property-methods-assignment/getter-and-setter/expected.js

@@ -1,17 +1,13 @@
 "use strict";
 
-var obj = (function (_obj) {
-  Object.defineProperties(_obj, {
-    foo: {
-      get: function () {
-        return 5 + 5;
-      },
-      set: function (value) {
-        this._foo = value;
-      },
-      enumerable: true
-    }
-  });
-
-  return _obj;
-})({});
+var obj = Object.defineProperties({}, {
+  foo: {
+    get: function () {
+      return 5 + 5;
+    },
+    set: function (value) {
+      this._foo = value;
+    },
+    enumerable: true
+  }
+});

test/fixtures/transformation/es5-property-methods-assignment/getter/expected.js

@@ -1,14 +1,10 @@
 "use strict";
 
-var obj = (function (_obj) {
-  Object.defineProperties(_obj, {
-    foo: {
-      get: function () {
-        return 5 + 5;
-      },
-      enumerable: true
-    }
-  });
-
-  return _obj;
-})({});
+var obj = Object.defineProperties({}, {
+  foo: {
+    get: function () {
+      return 5 + 5;
+    },
+    enumerable: true
+  }
+});

test/fixtures/transformation/es5-property-methods-assignment/setter/expected.js

@@ -1,14 +1,10 @@
 "use strict";
 
-var obj = (function (_obj) {
-  Object.defineProperties(_obj, {
-    foo: {
-      set: function (value) {
-        this._foo = value;
-      },
-      enumerable: true
-    }
-  });
-
-  return _obj;
-})({});
+var obj = Object.defineProperties({}, {
+  foo: {
+    set: function (value) {
+      this._foo = value;
+    },
+    enumerable: true
+  }
+});

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 _Foo = Foo;
+  var Test = function Test() {
+    woops["super"].test();
+    _Foo.call(this);
+    _Foo.prototype.test.call(this);
+    foob(_Foo);
 
-  Foo.call.apply(Foo, [this].concat(_slice.call(arguments)));
-  Foo.call.apply(Foo, [this, "test"].concat(_slice.call(arguments)));
+    _Foo.call.apply(_Foo, [this].concat(_slice.call(arguments)));
+    _Foo.call.apply(_Foo, [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)));
-};
+    _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)));
+  };
 
-_inherits(Test, Foo);
+  _inherits(Test, _Foo);
 
-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 () {
+    _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.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 () {
+    _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)));
+  };
+
+  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 _Foo = Foo;
+  var Test = function Test() {
+    _Foo.prototype.test;
+    _Foo.prototype.test.whatever;
+  };
 
-_inherits(Test, Foo);
+  _inherits(Test, _Foo);
+
+  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 _Foo = Foo;
+  var Test = function Test() {
+    _Foo.prototype.test.whatever();
+    _Foo.prototype.test.call(this);
+  };
 
-_inherits(Test, Foo);
+  _inherits(Test, _Foo);
 
-Test.test = function () {
-  return Foo.wow.call(this);
-};
+  Test.test = function () {
+    return _Foo.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 _Bar = Bar;
+  var Foo = function Foo() {
+    this.state = "test";
+  };
 
-_inherits(Foo, Bar);
+  _inherits(Foo, _Bar);
+
+  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 _Chaplin$Controller = Chaplin.Controller;
+  var BaseController = function BaseController() {
+    if (_Chaplin$Controller) {
+      _Chaplin$Controller.apply(this, arguments);
+    }
+  };
 
-_inherits(BaseController, Chaplin.Controller);
+  _inherits(BaseController, _Chaplin$Controller);
 
-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 _Chaplin$Controller$Another = Chaplin.Controller.Another;
+  var BaseController2 = function BaseController2() {
+    if (_Chaplin$Controller$Another) {
+      _Chaplin$Controller$Another.apply(this, arguments);
+    }
+  };
+
+  _inherits(BaseController2, _Chaplin$Controller$Another);
+
+  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 _Foo = Foo;
+  var Test = function Test() {
+    if (_Foo) {
+      _Foo.apply(this, arguments);
+    }
+  };
 
-_inherits(Test, Foo);
+  _inherits(Test, _Foo);
+
+  return Test;
+})();

test/fixtures/transformation/es6-computed-property-names/argument/expected.js

@@ -1,6 +1,12 @@
 "use strict";
 
-foo((function (_ref) {
-  _ref[bar] = "foobar";
-  return _ref;
-})({}));
+var _defineProperty = function (obj, key, value) {
+  return Object.defineProperty(obj, key, {
+    value: value,
+    enumerable: true,
+    configurable: true,
+    writable: true
+  });
+};
+
+foo(_defineProperty({}, bar, "foobar"));

test/fixtures/transformation/es6-computed-property-names/assignment/expected.js

@@ -1,6 +1,12 @@
 "use strict";
 
-foo = (function (_foo) {
-  _foo[bar] = "foobar";
-  return _foo;
-})({});
+var _defineProperty = function (obj, key, value) {
+  return Object.defineProperty(obj, key, {
+    value: value,
+    enumerable: true,
+    configurable: true,
+    writable: true
+  });
+};
+
+foo = _defineProperty({}, bar, "foobar");

test/fixtures/transformation/es6-computed-property-names/ignore-symbol/actual.js

@@ -0,0 +1,3 @@
+var foo = {
+  [Symbol.iterator]: "foobar"
+};

test/fixtures/transformation/es6-computed-property-names/ignore-symbol/expected.js

@@ -0,0 +1,8 @@
+"use strict";
+
+var foo = (function () {
+  var _foo = {};
+
+  _foo[Symbol.iterator] = "foobar";
+  return _foo;
+})();

test/fixtures/transformation/es6-computed-property-names/method/expected.js

@@ -1,9 +1,14 @@
 "use strict";
 
-var obj = (function (_obj) {
-  _obj[foobar] = function () {
-    return "foobar";
-  };
+var _defineProperty = function (obj, key, value) {
+  return Object.defineProperty(obj, key, {
+    value: value,
+    enumerable: true,
+    configurable: true,
+    writable: true
+  });
+};
 
-  return _obj;
-})({});
+var obj = _defineProperty({}, foobar, function () {
+  return "foobar";
+});

test/fixtures/transformation/es6-computed-property-names/mixed/expected.js

@@ -1,10 +1,24 @@
 "use strict";
 
-var obj = (function (_obj) {
-  _obj["x" + foo] = "heh";
-  _obj["y" + bar] = "noo";
+var _defineProperty = function (obj, key, value) {
+  return Object.defineProperty(obj, key, {
+    value: value,
+    enumerable: true,
+    configurable: true,
+    writable: true
+  });
+};
+
+var obj = (function () {
+  var _obj = {};
+
+  _defineProperty(_obj, "x" + foo, "heh");
+
+  _defineProperty(_obj, "y" + bar, "noo");
+
+  _defineProperty(_obj, "foo", "foo");
+
+  _defineProperty(_obj, "bar", "bar");
+
   return _obj;
-})({
-  foo: "foo",
-  bar: "bar"
-});
+})();

test/fixtures/transformation/es6-computed-property-names/multiple/expected.js

@@ -1,7 +1,20 @@
 "use strict";
 
-var obj = (function (_obj) {
-  _obj["x" + foo] = "heh";
-  _obj["y" + bar] = "noo";
+var _defineProperty = function (obj, key, value) {
+  return Object.defineProperty(obj, key, {
+    value: value,
+    enumerable: true,
+    configurable: true,
+    writable: true
+  });
+};
+
+var obj = (function () {
+  var _obj = {};
+
+  _defineProperty(_obj, "x" + foo, "heh");
+
+  _defineProperty(_obj, "y" + bar, "noo");
+
   return _obj;
-})({});
+})();

test/fixtures/transformation/es6-computed-property-names/single/expected.js

@@ -1,6 +1,12 @@
 "use strict";
 
-var obj = (function (_obj) {
-  _obj["x" + foo] = "heh";
-  return _obj;
-})({});
+var _defineProperty = function (obj, key, value) {
+  return Object.defineProperty(obj, key, {
+    value: value,
+    enumerable: true,
+    configurable: true,
+    writable: true
+  });
+};
+
+var obj = _defineProperty({}, "x" + foo, "heh");

test/fixtures/transformation/es6-computed-property-names/this/expected.js

@@ -1,7 +1,12 @@
 "use strict";
 
-var _this = this;
-var obj = (function (_obj) {
-  _obj["x" + _this.foo] = "heh";
-  return _obj;
-})({});
+var _defineProperty = function (obj, key, value) {
+  return Object.defineProperty(obj, key, {
+    value: value,
+    enumerable: true,
+    configurable: true,
+    writable: true
+  });
+};
+
+var obj = _defineProperty({}, "x" + this.foo, "heh");

test/fixtures/transformation/es6-computed-property-names/variable/expected.js

@@ -1,6 +1,12 @@
 "use strict";
 
-var foo = (function (_foo) {
-  _foo[bar] = "foobar";
-  return _foo;
-})({});
+var _defineProperty = function (obj, key, value) {
+  return Object.defineProperty(obj, key, {
+    value: value,
+    enumerable: true,
+    configurable: true,
+    writable: true
+  });
+};
+
+var foo = _defineProperty({}, bar, "foobar");

test/fixtures/transformation/es6-constants/destructuring/expected.js

@@ -5,6 +5,7 @@ var _slicedToArray = function (arr, i) {
     return arr;
   } else {
     var _arr = [];
+
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);
 
@@ -23,13 +24,15 @@ var a = _ref2[0];
 var b = _ref2[1];
 var _ref3 = [3, 4];
 
-var _ref4 = _slicedToArray(_ref3, 2);
+var _ref3 = _slicedToArray(_ref3, 2);
 
-var c = _ref4[0];
-var d = _ref4[1];
-var _ref5 = { e: 5, f: 6 };
-var e = _ref5.e;
-var f = _ref5.f;
-var _ref6 = { a: 7, b: 8 };
-var g = _ref6.a;
-var h = _ref6.b;
+var c = _ref3[0];
+var d = _ref3[1];
+var _ref4 = { e: 5, f: 6 };
+
+var e = _ref4.e;
+var f = _ref4.f;
+var _ref5 = { a: 7, b: 8 };
+
+var g = _ref5.a;
+var h = _ref5.b;

test/fixtures/transformation/es6-destructuring/array/expected.js

@@ -5,6 +5,7 @@ var _slicedToArray = function (arr, i) {
     return arr;
   } else {
     var _arr = [];
+
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);
 
@@ -20,10 +21,10 @@ var _ref = ["hello", [", ", "junk"], ["world"]];
 var _ref2 = _slicedToArray(_ref, 4);
 
 var a = _ref2[0];
-var _ref3 = _slicedToArray(_ref2[1], 1);
+var _ref2$1 = _slicedToArray(_ref2[1], 1);
 
-var b = _ref3[0];
-var _ref4 = _slicedToArray(_ref2[2], 1);
+var b = _ref2$1[0];
+var _ref2$2 = _slicedToArray(_ref2[2], 1);
 
-var c = _ref4[0];
+var c = _ref2$2[0];
 var d = _ref2[3];

test/fixtures/transformation/es6-destructuring/assignment-expression/expected.js

@@ -1,11 +1,12 @@
 "use strict";
 
-var _temp, _ref;
+var _temp, _temp2;
 var _slicedToArray = function (arr, i) {
   if (Array.isArray(arr)) {
     return arr;
   } else {
     var _arr = [];
+
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);
 
@@ -16,4 +17,4 @@ var _slicedToArray = function (arr, i) {
   }
 };
 
-console.log((_temp = [123], _ref = _slicedToArray(_temp, 1), x = _ref[0], _temp));
+console.log((_temp = [123], _temp2 = _slicedToArray(_temp, 1), x = _temp2[0], _temp));

test/fixtures/transformation/es6-destructuring/assignment-statement/expected.js

@@ -5,6 +5,7 @@ var _slicedToArray = function (arr, i) {
     return arr;
   } else {
     var _arr = [];
+
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);
 

test/fixtures/transformation/es6-destructuring/empty/expected.js

@@ -5,6 +5,7 @@ var _slicedToArray = function (arr, i) {
     return arr;
   } else {
     var _arr = [];
+
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);
 
@@ -20,10 +21,10 @@ var _ref = ["foo", "hello", [", ", "junk"], ["world"]];
 var _ref2 = _slicedToArray(_ref, 5);
 
 var a = _ref2[1];
-var _ref3 = _slicedToArray(_ref2[2], 1);
+var _ref2$2 = _slicedToArray(_ref2[2], 1);
 
-var b = _ref3[0];
-var _ref4 = _slicedToArray(_ref2[3], 1);
+var b = _ref2$2[0];
+var _ref2$3 = _slicedToArray(_ref2[3], 1);
 
-var c = _ref4[0];
+var c = _ref2$3[0];
 var d = _ref2[4];

test/fixtures/transformation/es6-destructuring/es7-object-rest/expected.js

@@ -2,6 +2,7 @@
 
 var _objectWithoutProperties = function (obj, keys) {
   var target = {};
+
   for (var i in obj) {
     if (keys.indexOf(i) >= 0) continue;
     if (!Object.prototype.hasOwnProperty.call(obj, i)) continue;

test/fixtures/transformation/es6-destructuring/for-in/expected.js

@@ -5,6 +5,7 @@ var _slicedToArray = function (arr, i) {
     return arr;
   } else {
     var _arr = [];
+
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);
 

test/fixtures/transformation/es6-destructuring/for-of/expected.js

@@ -5,6 +5,7 @@ var _slicedToArray = function (arr, i) {
     return arr;
   } else {
     var _arr = [];
+
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);
 

test/fixtures/transformation/es6-destructuring/member-expression/expected.js

@@ -5,6 +5,7 @@ var _slicedToArray = function (arr, i) {
     return arr;
   } else {
     var _arr = [];
+
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);
 

test/fixtures/transformation/es6-destructuring/mixed/expected.js

@@ -5,6 +5,7 @@ var _slicedToArray = function (arr, i) {
     return arr;
   } else {
     var _arr = [];
+
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);
 
@@ -15,11 +16,11 @@ var _slicedToArray = function (arr, i) {
   }
 };
 
-var _ref = _slicedToArray(rect.topLeft, 2);
+var _rect$topLeft = _slicedToArray(rect.topLeft, 2);
 
-var x1 = _ref[0];
-var y1 = _ref[1];
-var _ref2 = _slicedToArray(rect.bottomRight, 2);
+var x1 = _rect$topLeft[0];
+var y1 = _rect$topLeft[1];
+var _rect$bottomRight = _slicedToArray(rect.bottomRight, 2);
 
-var x2 = _ref2[0];
-var y2 = _ref2[1];
+var x2 = _rect$bottomRight[0];
+var y2 = _rect$bottomRight[1];

test/fixtures/transformation/es6-destructuring/parameters/expected.js

@@ -5,6 +5,7 @@ var _slicedToArray = function (arr, i) {
     return arr;
   } else {
     var _arr = [];
+
     for (var _iterator = arr[Symbol.iterator](), _step; !(_step = _iterator.next()).done;) {
       _arr.push(_step.value);
 
@@ -30,17 +31,17 @@ function unpackObject(_ref2) {
 
 console.log(unpackObject({ title: "title", author: "author" }));
 
-var unpackArray = function (_ref3, _ref5) {
-  var _ref4 = _slicedToArray(_ref3, 3);
+var unpackArray = function (_ref3, _ref4) {
+  var _ref3 = _slicedToArray(_ref3, 3);
 
-  var a = _ref4[0];
-  var b = _ref4[1];
-  var c = _ref4[2];
-  var _ref6 = _slicedToArray(_ref5, 3);
+  var a = _ref3[0];
+  var b = _ref3[1];
+  var c = _ref3[2];
+  var _ref4 = _slicedToArray(_ref4, 3);
 
-  var x = _ref6[0];
-  var y = _ref6[1];
-  var z = _ref6[2];
+  var x = _ref4[0];
+  var y = _ref4[1];
+  var z = _ref4[2];
   return a + b + c;
 };
 

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-common/exports-default-non-function/actual.js

@@ -0,0 +1,3 @@
+export default new Cachier()
+
+export function Cachier(databaseName) {}

test/fixtures/transformation/es6-modules-common/exports-default-non-function/expected.js

@@ -0,0 +1,6 @@
+"use strict";
+
+exports.Cachier = Cachier;
+exports["default"] = new Cachier();
+function Cachier(databaseName) {}
+module.exports = Object.assign(exports["default"], exports);

test/fixtures/transformation/es6-modules-common/overview/actual.js

@@ -8,5 +8,3 @@ import {foo as bar} from "foo";
 
 export {test};
 export var test = 5;
-
-export default test;

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

@@ -18,5 +18,3 @@ var bar = require("foo").bar;
 var bar = require("foo").foo;
 exports.test = test;
 var test = exports.test = 5;
-
-exports = module.exports = test;

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"] = {};