v1.15.0

CHANGELOG.md

@@ -1,239 +1,280 @@
-# 1.14.6
+# Changelog
+
+Gaps between patch versions are faulty/broken releases.
+
+## 1.15.0
+
+ * Don't alias `GeneratorFunction` and check the name which causes minifiers to remove the name and throw an error later on when we check if it's set.
+
+## 1.14.18
+
+ * Fix files only containg comments not being output.
+ * Fix duplicate comments on property key shorthands.
+
+## 1.14.17
+
+ * Add default initializer to let variables within loop bodies.
+ * Fix excessive `break` replacement inside of switches in let scoping.
+
+## 1.14.16
+
+ * Add object getter memos and this shorthand to playground.
+ * Fix while loops in let scoping.
+ * Upgrade `acorn-6to5`.
+
+## 1.14.14
+
+ * Fix template literals escaping.
+
+## 1.14.13
+
+ * Fix let scoping of `while` loops.
+ * Make class methods enumerable.
+
+## 1.14.12
+
+ * Fix duplicate dynamic expressions in call spread.
+
+## 1.14.10
+
+ * Fix let scoping unneccesary override.
+
+## 1.14.6
 
  * Avoid ensuring a block on non-array node replacements.
 
-# 1.14.5
+## 1.14.5
 
  * Upgrade `acorn-6to5`.
  * Fix JSON recursion error for unknown code generator node types.
  * Ensure that a statement is a block on block/statement types when replacing them with multiple nodes.
 
-# 1.14.4
+## 1.14.4
 
  * Merge pretzel maps and method binding.
 
-# 1.14.3
+## 1.14.3
 
  * Add playground pretzel maps.
 
-# 1.14.2
+## 1.14.2
 
  * Fix `commonInterop` default export handling.
  * Fix keyworded property key identifiers being turned into computed property key literals.
 
-# 1.14.1
+## 1.14.1
 
  * Inherit comments from `ClassDeclaration`.
 
-# 1.14.0
+## 1.14.0
 
  * Add [playground](https://6to5.github.io/playground.html).
 
-# 1.13.13
+## 1.13.13
 
  * Fix `--debug` in `bin/6to5-node`. Thanks [@timoxley](https://github.com/timoxley).
 
-# 1.13.12
+## 1.13.12
 
  * Ignore `XJSEmptyExpression`s in `react` transformer output.
 
-# 1.13.11
+## 1.13.11
 
  * Fix `util.regexify` on falsy values.
  * Fix `_aliasFunction` with rest parameters.
  * Export as `module.exports` instead of `exports.default` if there are no other `ExportDeclaration`s in `commonInterop` module formatter.
  * Add `system` module formatter. Thanks [@douglasduteil](https://github.com/douglasduteil).
 
-# 1.13.10
+## 1.13.10
 
  * Add support for `AssignmentExpression` destructuring outside of `ExpressionStatement`.
 
-# 1.13.9
+## 1.13.9
 
  * Fix `VirtualPropertyExpression` visitor keys.
 
-# 1.13.8
+## 1.13.8
 
  * Only use a single reference in abstract references.
 
-# 1.13.7
+## 1.13.7
 
  * Upgrade `acorn-6to5`.
  * Add experimental exponentiation operator support.
 
-# 1.13.6
+## 1.13.6
 
  * Fix experimental object spread/rest helper.
 
-# 1.13.5
+## 1.13.5
 
  * Upgrade `acorn-6to5`.
  * Add experimental support for object spread/rest.
  * Change `arguments` to array to an additional helper method.
 
-# 1.13.4
+## 1.13.4
 
  * Fix single spread element returning itself.
 
-# 1.13.3
+## 1.13.3
 
  * Upgrade `acorn-6to5`.
  * Add experimental support for abstract references.
 
-# 1.13.2
+## 1.13.2
 
  * Optimise `Array.from` usage by adding a helper method.
  * Upgrade `acorn-6to5`.
 
-# 1.13.1
+## 1.13.1
 
  * Fix constructor spread optimisation. Thanks [@zloirock](https://github.com/zloirock).
 
-# 1.13.0
+## 1.13.0
 
  * Put experimental ES7 features behind a flag `--experimental` and `experimental` option.
  * Constructor spread performance increase. Thanks [@RReverser](https://github.com/RReverser).
  * Use `self` instead of `window` in the optional 6to5 runtime. Thanks [@RReverser](https://github.com/RReverser).
 
-# 1.12.26
+## 1.12.26
 
  * Support computed property destructuring.
 
-# 1.12.25
+## 1.12.25
 
  * Update `acorn-6to5`, `ast-types`, `es6-shim`, `chokidar`, `estraverse` and `private`.
 
-# 1.12.24
+## 1.12.24
 
  * Collect references that haven't been declared in scope.
 
-# 1.12.23
+## 1.12.23
 
  * Fix generator function export hoisting.
 
-# 1.12.22
+## 1.12.22
 
  * Update `fs-readdir-recursive` and `chokidar`.
  * Support array destructuring on iterables.
  * Make amd module id optional. Thanks [@webpro](https://github.com/webpro).
 
-# 1.12.21
+## 1.12.21
 
  * Fix unneccesary let scoping replacement.
  * Add `commonInterop` module formatter. Thanks [@Naddiseo](https://github.com/Naddiseo).
  * Fix `return` outside of function body bug. Thanks [@brentburg](https://github.com/brentburg).
  * Add more flexible option types.
 
-# 1.12.20
+## 1.12.20
 
  * Append `sourceMappingURL` when using `bin/6to5` and output sourcemaps.
 
-# 1.12.19
+## 1.12.19
 
  * Add `comments` option and `--remove-comments` flag. Thanks [@webpro](htps://github.com/webpro).
  * Embed `regenerator`.
 
-# 1.12.18
+## 1.12.18
 
  * Use `global` reference instead of `window`.
 
-# 1.12.17
+## 1.12.17
 
  * Add `moduleName`, `sourceRoot` and `filenameRelative` options. Thanks [@darvelo](https://github.com/darvelo).
  * Traversal optimisations.
 
-# 1.12.16
+## 1.12.16
 
  * Fix comments not being retained from `MethodDefinition` in classes.
  * Add temporal dead zone in default parameters.
 
-# 1.12.15
+## 1.12.15
 
  * Update `acorn-6to5`.
 
-# 1.12.14
+## 1.12.14
 
  * Fix duplicate let scoping in functions.
  * Make JSX whitespace more React-compliant.
  * Add `_memberExpressionKeywords` transformer that turns keyword identifiers to computed literals.
  * Upgrade `regenerator-6to5`.
 
-# 1.12.13
+## 1.12.13
 
  * Support duplicate constants within different block scopes.
  * Fix for-head duplication testing and replacement.
  * Support `raw` property on tagged template literals.
 
-# 1.12.12
+## 1.12.12
 
  * Make scope tracker more reliable to handle all edgecases.
 
-# 1.12.11
+## 1.12.11
 
  * Block scope classes.
  * Fix generation of integer `Literal`s in `MemberExpression`.
 
-# 1.12.10
+## 1.12.10
 
  * Fix let scoping var hoisting.
 
-# 1.12.9
+## 1.12.9
 
  * Escape unicode characters when generating string `Literal`s.
  * Fix semicolons being output for statements in `ExportDeclaration`.
  * Fix `WithStatement` missing parenthesis.
 
-# 1.12.8
+## 1.12.8
 
  * Temporarily forbid `AssignmentExpression` destructuring outside of `ExpressionStatement`.
 
-# 1.12.7
+## 1.12.7
 
  * Update to latest `acorn-6to5`.
 
-# 1.12.6
+## 1.12.6
 
  * Update to latest `acorn-6to5`.
 
-# 1.12.5
+## 1.12.5
 
  * Fix excessive whitespace trimming resulting in innaccurate sourcemap line.
 
-# 1.12.4
+## 1.12.4
 
  * Add `doc` folder for documentation.
 
-# 1.12.3
+## 1.12.3
 
  * Support generator comprehensions.
  * Use `Array.from` instead of `Array.prototype.slice` in spread transformer.
  * Support spread in `NewExpression`s.
 
-# 1.12.2
+## 1.12.2
 
  * Upgrade `matcha` to `0.6.0` and `browserify` to `6.3.2`.
  * Add own `trimRight` helper instead of relying on the string instance method.
  * Support JSX spreads that aren't the first.
 
-# 1.12.1
+## 1.12.1
 
  * Fix `this` and `arguments` mapping in the `_aliasFunctions` transformer.
 
-# 1.12.0
+## 1.12.0
 
  * Combine `jsx` and `react` transformers to `react`.
  * Update `react` syntax output to React v0.12.
 
-# 1.11.15
+## 1.11.15
 
  * Fix JSX literal whitespace generation.
 
-# 1.11.14
+## 1.11.14
 
  * Avoid using a switch for let-scoping continue and break statements and use an if statement instead.
  * Remove excess whitespace and newlines from JSX literals.
 
-# 1.11.13
+## 1.11.13
 
  * Update regenerator-6to5
  * Add support for most escodegen formatting options

Makefile

@@ -16,7 +16,7 @@ bench:
 	node node_modules/matcha/bin/_matcha
 
 lint:
-	$(JSHINT_CMD) lib bin benchmark/index.js
+	$(JSHINT_CMD) --reporter node_modules/jshint-stylish/stylish.js lib bin benchmark/index.js
 
 test-clean:
 	rm -rf test/tmp

bin/6to5-node

@@ -15,15 +15,18 @@ process.argv.slice(2).forEach(function(arg){
     case "-d":
       args.unshift("--debug");
       break;
+
     case "debug":
     case "--debug":
     case "--debug-brk":
       args.unshift(arg);
       break;
+
     case "-gc":
     case "--expose-gc":
       args.unshift("--expose-gc");
       break;
+
     case "--gc-global":
     case "--harmony":
     case "--harmony-proxies":
@@ -35,16 +38,20 @@ process.argv.slice(2).forEach(function(arg){
     case "--trace-deprecation":
       args.unshift(arg);
       break;
+
     default:
-      if (0 == arg.indexOf("--trace")) args.unshift(arg);
-      else args.push(arg);
+      if (arg.indexOf("--trace") === 0) {
+        args.unshift(arg);
+      } else {
+        args.push(arg);
+      }
       break;
   }
 });
 
 var proc = spawn(process.argv[0], args, { stdio: "inherit" });
 proc.on("exit", function (code, signal) {
-  process.on("exit", function (){
+  process.on("exit", function () {
     if (signal) {
       process.kill(process.pid, signal);
     } else {

doc/differences.md

@@ -17,7 +17,7 @@ var seattlers = [for (c of customers) if (c.city == "Seattle") { name: c.name, a
 is generated to the following with 6to5:
 
 ```javascript
-var seattlers = customers.filter(function (c) {
+var seattlers = Array.from(customers).filter(function (c) {
   return c.city == "Seattle";
 }).map(function (c) {
   return {
@@ -51,8 +51,7 @@ As you can tell, it's not very pretty, unreadable even. Instead of mapping
 directly to a runtime, like other transpilers, 6to5 maps directly to the
 equivalent ES5.
 
-I'm not saying 6to5 is for everyone or even suited for everything. Traceur is
-better suited if you'd like a full ES6 environment with polyfills and all.
+Sometimes there are little things that 6to5 needs
 
 ## Comparison to other transpilers
 

doc/playground.md

@@ -18,6 +18,8 @@ to5.transform("code", { playground: true });
 
  * [Memoization operator](#memoization-operator)
  * [Method binding](#method-binding)
+ * [Object getter memoization](#object-getter-memoization)
+ * [This shorthand](#this-shorthand)
 
 ### Memoization assignment operator
 
@@ -66,3 +68,53 @@ var fn = obj.method.bind(obj, "foob");
 ["foo", "bar"].map(function (val) { return val.toUpperCase(); });
 [1.1234, 23.53245, 3].map(function (val) { return val.toFixed(2); });
 ```
+
+### Object getter memoization
+
+```javascript
+var foo = {
+  memo bar() {
+    return complex();
+  }
+};
+
+class Foo {
+  memo bar() {
+    return complex();
+  }
+}
+```
+
+equivalent to
+
+```javascript
+var foo = {
+  get bar() {
+    if (this._barRan) return this._bar;
+    this._barRan = true;
+    return this._bar = complex();
+  }
+};
+
+class Foo {
+  get bar() {
+    if (this._barRan) return this._bar;
+    this._barRan = true;
+    return this._bar = complex();
+  }
+}
+```
+
+**NOTE:** Memoised functions will return the result of the **first** execution, regardless of arguments.
+
+### This shorthand
+
+```javascript
+@foo
+```
+
+equivalent to
+
+```javascirpt
+this.foo
+```

lib/6to5/file.js

@@ -41,7 +41,8 @@ File.normaliseOptions = function (opts) {
     filename:     "unknown",
     modules:      "common",
     runtime:      false,
-    code:         true
+    code:         true,
+    ast:          true
   });
 
   // normalise windows path separators to unix
@@ -186,15 +187,18 @@ File.prototype.generate = function () {
   var opts = this.opts;
   var ast  = this.ast;
 
-  if (!opts.code) {
-    return {
-      code: "",
-      map:  null,
-      ast:  ast
-    };
-  }
+  var result = {
+    code: "",
+    map: null,
+    ast: null
+  };
 
-  var result = generate(ast, opts, this.code);
+  if (opts.ast) result.ast = ast;
+  if (!opts.code) return result;
+
+  var _result = generate(ast, opts, this.code);
+  result.code = _result.code;
+  result.map  = _result.map;
 
   if (this.shebang) {
     // add back shebang
@@ -205,8 +209,6 @@ File.prototype.generate = function () {
     result.code += "\n" + util.sourceMapToComment(result.map);
   }
 
-  result.ast = result;
-
   return result;
 };
 

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

@@ -28,7 +28,13 @@ exports.before = {
 };
 
 exports.after = {
-  nodes: {},
+  nodes: {
+    AssignmentExpression: function (node) {
+      if (t.isFunction(node.right)) {
+        return 1;
+      }
+    }
+  },
 
   list: {
     VariableDeclaration: function (node) {

lib/6to5/register.js

@@ -1,7 +1,6 @@
 require("./polyfill");
 
 var sourceMapSupport = require("source-map-support");
-var roadrunner       = require('roadrunner');
 var util             = require("./util");
 var to5              = require("./index");
 var fs               = require("fs");
@@ -79,15 +78,19 @@ var loader = function (m, filename) {
 
   var result;
 
-  if (cache && cache[filename].mtime === mtime(filename)) {
-    result = cache[filename];
+  if (cache) {
+    var cached = cache[filename];
+    if (cached && cached.mtime === mtime(filename)) {
+      result = cached;
+    }
   }
 
   result = result || to5.transformFileSync(filename, _.extend({
     whitelist: whitelist,
     blacklist: blacklist,
     sourceMap: true,
-    modules:   "commonInterop"
+    modules:   "commonInterop",
+    ast:       false
   }, transformOpts));
 
   if (cache) {
@@ -126,7 +129,7 @@ module.exports = function (opts) {
 
   if (opts.extensions) hookExtensions(util.arrayify(opts.extensions));
 
-  if (opts.cache) cache = roadrunner.get('6to5');
+  if (opts.cache) cache = opts.cache;
   if (opts.cache === false) cache = null;
 
   _.extend(transformOpts, opts);

lib/6to5/transformation/transform.js

@@ -29,6 +29,11 @@ transform.moduleFormatters = {
 };
 
 _.each({
+  // plyground
+  methodBinding:             require("./transformers/playground-method-binding"),
+  memoizationOperator:       require("./transformers/playground-memoization-operator"),
+  objectGetterMemoization:   require("./transformers/playground-object-getter-memoization"),
+
   modules:                   require("./transformers/es6-modules"),
   propertyNameShorthand:     require("./transformers/es6-property-name-shorthand"),
   arrayComprehension:        require("./transformers/es7-array-comprehension"),
@@ -56,10 +61,6 @@ _.each({
 
   generators:                require("./transformers/es6-generators"),
 
-  // plyground
-  methodBinding:             require("./transformers/playground-method-binding"),
-  memoizationOperator:       require("./transformers/playground-memoization-operator"),
-
   _blockHoist:               require("./transformers/_block-hoist"),
   _declarations:             require("./transformers/_declarations"),
   _aliasFunctions:           require("./transformers/_alias-functions"),

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

@@ -162,17 +162,22 @@ Class.prototype.buildBody = function () {
 Class.prototype.pushMethod = function (node) {
   var methodName = node.key;
 
-  var mutatorMap = this.instanceMutatorMap;
-  if (node.static) mutatorMap = this.staticMutatorMap;
-
   var kind = node.kind;
 
   if (kind === "") {
-    kind = "value";
-    util.pushMutatorMap(mutatorMap, methodName, "writable", t.identifier("true"));
-  }
+    // method
 
-  util.pushMutatorMap(mutatorMap, methodName, kind, node);
+    var className = this.className;
+    if (!node.static) className = t.memberExpression(className, t.identifier("prototype"));
+    methodName = t.memberExpression(className, methodName, node.computed);
+
+    this.body.push(t.expressionStatement(t.assignmentExpression("=", methodName, node.value)));
+  } else {
+    // mutator
+    var mutatorMap = this.instanceMutatorMap;
+    if (node.static) mutatorMap = this.staticMutatorMap;
+    util.pushMutatorMap(mutatorMap, methodName, kind, node);
+  }
 };
 
 /**

lib/6to5/transformation/transformers/es6-default-parameters.js

@@ -11,7 +11,7 @@ exports.Function = function (node, parent, file, scope) {
     return t.getIds(param);
   });
 
-  var closure = false;
+  var iife = false;
 
   _.each(node.defaults, function (def, i) {
     if (!def) return;
@@ -29,7 +29,7 @@ exports.Function = function (node, parent, file, scope) {
         }
 
         if (scope.has(node.name)) {
-          closure = true;
+          iife = true;
         }
       };
 
@@ -40,7 +40,7 @@ exports.Function = function (node, parent, file, scope) {
     // we're accessing a variable that's already defined within this function
     var has = scope.get(param.name);
     if (has && !_.contains(node.params, has)) {
-      closure = true;
+      iife = true;
     }
   });
 
@@ -55,7 +55,7 @@ exports.Function = function (node, parent, file, scope) {
     }, true));
   });
 
-  if (closure) {
+  if (iife) {
     var container = t.functionExpression(null, [], node.body, node.generator);
     container._aliasFunction = true;
 

lib/6to5/transformation/transformers/es6-generators/runtime.js

@@ -27,20 +27,14 @@ var ContinueSentinel = {};
 
 // Dummy constructor that we use as the .constructor property for
 // functions that return Generator objects.
-var GF = function GeneratorFunction() {};
+function GeneratorFunction() {}
 var GFp = function GeneratorFunctionPrototype() {};
 var Gp = GFp.prototype = Generator.prototype;
-(GFp.constructor = GF).prototype =
-  Gp.constructor = GFp;
-
-// Ensure isGeneratorFunction works when Function#name not supported.
-var GFName = "GeneratorFunction";
-if (GF.name !== GFName) GF.name = GFName;
-if (GF.name !== GFName) throw new Error(GFName + " renamed?");
+(GFp.constructor = GeneratorFunction).prototype = Gp.constructor = GFp;
 
 runtime.isGeneratorFunction = function (genFun) {
   var ctor = genFun && genFun.constructor;
-  return ctor ? GF.name === ctor.name : false;
+  return ctor ? GeneratorFunction.name === ctor.name : false;
 };
 
 runtime.mark = function (genFun) {

lib/6to5/transformation/transformers/es6-let-scoping.js

@@ -27,7 +27,7 @@ exports.VariableDeclaration = function (node) {
   isLet(node);
 };
 
-exports.For = function (node, parent, file, scope) {
+exports.Loop = function (node, parent, file, scope) {
   var init = node.left || node.init;
   if (isLet(init)) {
     t.ensureBlock(node);
@@ -49,7 +49,7 @@ exports.For = function (node, parent, file, scope) {
 };
 
 exports.BlockStatement = function (block, parent, file, scope) {
-  if (!t.isFor(parent)) {
+  if (!t.isLoop(parent)) {
     var letScoping = new LetScoping(false, block, parent, file, scope);
     letScoping.run();
   }
@@ -58,19 +58,19 @@ exports.BlockStatement = function (block, parent, file, scope) {
 /**
  * Description
  *
- * @param {Boolean|Node} forParent
+ * @param {Boolean|Node} loopParent
  * @param {Node} block
  * @param {Node} parent
  * @param {File} file
  * @param {Scope} scope
  */
 
-function LetScoping(forParent, block, parent, file, scope) {
-  this.forParent = forParent;
-  this.parent    = parent;
-  this.scope     = scope;
-  this.block     = block;
-  this.file      = file;
+function LetScoping(loopParent, block, parent, file, scope) {
+  this.loopParent = loopParent;
+  this.parent     = parent;
+  this.scope      = scope;
+  this.block      = block;
+  this.file       = file;
 
   this.letReferences = {};
   this.body          = [];
@@ -91,6 +91,9 @@ LetScoping.prototype.run = function () {
   // remap all let references that exist in upper scopes to their uid
   this.remap();
 
+  // add default initializer to let variables in loop bodys
+  this.initialiseLoopLets();
+
   // this is a block within a `Function` so we can safely leave it be
   if (t.isFunction(this.parent)) return this.noClosure();
 
@@ -106,7 +109,7 @@ LetScoping.prototype.run = function () {
 
   // if we're inside of a for loop then we search to see if there are any
   // `break`s, `continue`s, `return`s etc
-  this.has = this.checkFor();
+  this.has = this.checkLoop();
 
   // hoist var references to retain scope
   this.hoistVarDeclarations();
@@ -172,11 +175,11 @@ LetScoping.prototype.remap = function () {
     traverse(node, replace);
   };
 
-  var forParent = this.forParent;
-  if (forParent) {
-    traverseReplace(forParent.right, forParent);
-    traverseReplace(forParent.test, forParent);
-    traverseReplace(forParent.update, forParent);
+  var loopParent = this.loopParent;
+  if (loopParent) {
+    traverseReplace(loopParent.right, loopParent);
+    traverseReplace(loopParent.test, loopParent);
+    traverseReplace(loopParent.update, loopParent);
   }
 
   traverse(block, replace);
@@ -244,6 +247,30 @@ LetScoping.prototype.getInfo = function () {
   return opts;
 };
 
+/**
+ * Any let variable declared within a loop body need to have an initializer or
+ * else they'll be hoisted and subsequent iterations of the loop will have a
+ * previous state. This function adds a default initializer of `undefined` to
+ * those variables.
+ */
+
+LetScoping.prototype.initialiseLoopLets = function () {
+  var loopParent = this.loopParent;
+  if (!loopParent) return;
+
+  traverse(this.block, function (node) {
+    if (t.isFunction(node) || t.isLoop(node)) {
+      return false;
+    }
+
+    if (isLet(node)) {
+      _.each(node.declarations, function (declar) {
+        declar.init = declar.init || t.identifier("undefined");
+      });
+    }
+  });
+};
+
 /**
  * If we're inside of a `For*Statement` then traverse it and check if it has one
  * of the following node types `ReturnStatement`, `BreakStatement`,
@@ -253,24 +280,24 @@ LetScoping.prototype.getInfo = function () {
  * @returns {Object}
  */
 
-LetScoping.prototype.checkFor = function () {
+LetScoping.prototype.checkLoop = function () {
   var has = {
     hasContinue: false,
     hasReturn:   false,
     hasBreak:    false,
   };
 
-  var forParent = this.forParent;
-
-  traverse(this.block, function (node) {
+  traverse(this.block, function (node, parent) {
     var replace;
 
-    if (t.isFunction(node) || t.isFor(node)) {
+    if (t.isFunction(node) || t.isLoop(node)) {
       return false;
     }
 
-    if (forParent && node && !node.label) {
+    if (node && !node.label) {
       if (t.isBreakStatement(node)) {
+        if (t.isSwitchCase(parent)) return;
+
         has.hasBreak = true;
         replace = t.returnStatement(t.literal("break"));
       } else if (t.isContinueStatement(node)) {
@@ -367,7 +394,7 @@ LetScoping.prototype.getLetReferences = function () {
       });
 
       return false;
-    } else if (t.isFor(node)) {
+    } else if (t.isLoop(node)) {
       return false;
     }
   });
@@ -430,7 +457,7 @@ LetScoping.prototype.buildHas = function (ret, call) {
     t.variableDeclarator(ret, call)
   ]));
 
-  var forParent = this.forParent;
+  var loopParent = this.loopParent;
   var retCheck;
   var has = this.has;
   var cases = [];
@@ -445,7 +472,7 @@ LetScoping.prototype.buildHas = function (ret, call) {
   if (has.hasBreak || has.hasContinue) {
     // ensure that the parent has a label as we're building a switch and we
     // need to be able to access it
-    var label = forParent.label = forParent.label || this.file.generateUidIdentifier("loop", this.scope);
+    var label = loopParent.label = loopParent.label || this.file.generateUidIdentifier("loop", this.scope);
 
     if (has.hasBreak) {
       cases.push(t.switchCase(t.literal("break"), [t.breakStatement(label)]));

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

@@ -56,7 +56,7 @@ exports.ArrayExpression = function (node, parent, file) {
   return t.callExpression(t.memberExpression(first, t.identifier("concat")), nodes);
 };
 
-exports.CallExpression = function (node, parent, file) {
+exports.CallExpression = function (node, parent, file, scope) {
   var args = node.arguments;
   if (!hasSpread(args)) return;
 
@@ -79,10 +79,16 @@ exports.CallExpression = function (node, parent, file) {
   }
 
   var callee = node.callee;
+  var temp;
 
   if (t.isMemberExpression(callee)) {
     contextLiteral = callee.object;
 
+    if (t.isDynamic(contextLiteral)) {
+      temp = contextLiteral = scope.generateTemp(file);
+      callee.object = t.assignmentExpression("=", temp, callee.object);
+    }
+
     if (callee.computed) {
       callee.object = t.memberExpression(callee.object, callee.property, true);
       callee.property = t.identifier("apply");

lib/6to5/transformation/transformers/es6-template-literals.js

@@ -31,7 +31,7 @@ exports.TemplateLiteral = function (node) {
   var nodes = [];
 
   _.each(node.quasis, function (elem) {
-    nodes.push(t.literal(elem.value.raw));
+    nodes.push(t.literal(elem.value.cooked));
 
     var expr = node.expressions.shift();
     if (expr) {

lib/6to5/transformation/transformers/es7-abstract-references.js

@@ -30,12 +30,7 @@ exports.AssignmentExpression = function (node, parent, file, scope) {
   if (!t.isExpressionStatement(parent)) {
     // `node.right` isn't a simple identifier so we need to reference it
     if (t.isDynamic(value)) {
-      var tempName = file.generateUid("temp");
-      temp = value = t.identifier(tempName);
-      scope.push({
-        key: tempName,
-        id: temp
-      });
+      temp = value = scope.generateTemp(file);
     }
   }
 
@@ -75,12 +70,7 @@ exports.CallExpression = function (node, parent, file, scope) {
   var temp;
   if (t.isDynamic(callee.object)) {
     // we need to save `callee.object` so we can call it again
-    var tempName = file.generateUid("temp");
-    temp = t.identifier(tempName);
-    scope.push({
-      key: tempName,
-      id: temp
-    });
+    temp = scope.generateTemp(file);
   }
 
   var call = util.template("abstract-expression-call", {

lib/6to5/transformation/transformers/playground-method-binding.js

@@ -7,12 +7,7 @@ exports.BindMemberExpression = function (node, parent, file, scope) {
 
   var temp;
   if (t.isDynamic(object)) {
-    var tempName = file.generateUid("temp", scope);
-    temp =  object = t.identifier(tempName);
-    scope.push({
-      key: tempName,
-      id: temp
-    });
+    temp = object = scope.generateTemp(file);
   }
 
   var call = t.callExpression(
@@ -39,17 +34,12 @@ exports.BindFunctionExpression = function (node, parent, file, scope) {
   };
 
   if (_.find(node.arguments, t.isDynamic)) {
-    var argsIdName = file.generateUid("args", scope);
-    var argsId = t.identifier(argsIdName);
-    scope.push({
-      key: argsIdName,
-      id: argsId
-    });
+    var temp = scope.generateTemp(file, "args");
 
     return t.sequenceExpression([
-      t.assignmentExpression("=", argsId, t.arrayExpression(node.arguments)),
+      t.assignmentExpression("=", temp, t.arrayExpression(node.arguments)),
       buildCall(node.arguments.map(function (node, i) {
-        return t.memberExpression(argsId, t.literal(i), true);
+        return t.memberExpression(temp, t.literal(i), true);
       }))
     ]);
   } else {

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

@@ -0,0 +1,37 @@
+var traverse = require("../../traverse");
+var t        = require("../../types");
+
+exports.Property =
+exports.MethodDefinition = function (node, parent, file, scope) {
+  if (node.kind !== "memo") return;
+  node.kind = "get";
+
+  var value = node.value;
+  t.ensureBlock(value);
+
+  var body  = value.body.body;
+  var key   = node.key;
+
+  if (t.isIdentifier(key) && !node.computed) {
+    key = "_" + key.name;
+  } else {
+    key = file.generateUid("memo", scope);
+  }
+
+  var memoId = t.memberExpression(t.thisExpression(), t.identifier(key));
+  var doneId = t.memberExpression(t.thisExpression(), t.identifier(key + "Done"));
+
+  traverse(value, function (node) {
+    if (t.isFunction(node)) return;
+
+    if (t.isReturnStatement(node) && node.argument) {
+      node.argument = t.assignmentExpression("=", memoId, node.argument);
+    }
+  });
+
+  // this._barDone = true;
+  body.unshift(t.expressionStatement(t.assignmentExpression("=", doneId, t.literal(true))));
+
+  // if (this._barDone) return this._bar;
+  body.unshift(t.ifStatement(doneId, t.returnStatement(memoId)));
+};

lib/6to5/traverse/scope.js

@@ -23,7 +23,16 @@ function Scope(block, parent) {
 
 Scope.add = function (node, references) {
   if (!node) return;
-  _.merge(references, t.getIds(node, true));
+  _.defaults(references, t.getIds(node, true));
+};
+
+Scope.prototype.generateTemp = function (file, name) {
+    var id = file.generateUidIdentifier(name || "temp", this);
+    this.push({
+      key: id.name,
+      id: id
+    });
+    return id;
 };
 
 Scope.prototype.getReferences = function () {

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

@@ -3,13 +3,13 @@
   "BreakStatement":      ["Statement"],
   "ContinueStatement":   ["Statement"],
   "DebuggerStatement":   ["Statement"],
-  "DoWhileStatement":    ["Statement"],
+  "DoWhileStatement":    ["Statement", "Loop", "While"],
   "IfStatement":         ["Statement"],
   "ReturnStatement":     ["Statement"],
   "SwitchStatement":     ["Statement"],
   "ThrowStatement":      ["Statement"],
   "TryStatement":        ["Statement"],
-  "WhileStatement":      ["Statement"],
+  "WhileStatement":      ["Statement", "Loop", "While"],
   "WithStatement":       ["Statement"],
   "EmptyStatement":      ["Statement"],
   "LabeledStatement":    ["Statement"],
@@ -35,9 +35,9 @@
   "ClassDeclaration": ["Statement", "Declaration", "Class"],
   "ClassExpression":  ["Class"],
 
-  "ForOfStatement": ["Statement", "For", "Scope"],
-  "ForInStatement": ["Statement", "For", "Scope"],
-  "ForStatement":   ["Statement", "For", "Scope"],
+  "ForOfStatement": ["Statement", "For", "Scope", "Loop"],
+  "ForInStatement": ["Statement", "For", "Scope", "Loop"],
+  "ForStatement":   ["Statement", "For", "Scope", "Loop"],
 
   "ObjectPattern": ["Pattern"],
   "ArrayPattern":  ["Pattern"],

lib/6to5/types/index.js

@@ -162,7 +162,7 @@ t.toIdentifier = function (name) {
     return c ? c.toUpperCase() : "";
   });
 
-  return name;
+  return name || '_';
 };
 
 t.isValidIdentifier = function (name) {

package.json

@@ -1,7 +1,7 @@
 {
   "name": "6to5",
   "description": "Turn ES6 code into readable vanilla ES5 with source maps",
-  "version": "1.14.7",
+  "version": "1.15.0",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://github.com/6to5/6to5",
   "repository": {
@@ -35,7 +35,7 @@
     "test": "make test"
   },
   "dependencies": {
-    "acorn-6to5": "0.9.1-11",
+    "acorn-6to5": "0.9.1-12",
     "ast-types": "0.6.5",
     "chokidar": "0.11.1",
     "commander": "2.5.0",
@@ -48,18 +48,18 @@
     "mkdirp": "0.5.0",
     "private": "0.1.6",
     "regexpu": "0.3.0",
-    "roadrunner": "^1.0.4",
     "source-map": "0.1.40",
     "source-map-support": "0.2.8"
   },
   "devDependencies": {
+    "browserify": "6.3.2",
+    "chai": "^1.9.2",
     "istanbul": "0.3.2",
+    "jshint": "2.5.10",
+    "jshint-stylish": "^1.0.0",
     "matcha": "0.6.0",
     "mocha": "1.21.4",
-    "uglify-js": "2.4.15",
-    "browserify": "6.3.2",
     "rimraf": "2.2.8",
-    "jshint": "2.5.10",
-    "chai": "^1.9.2"
+    "uglify-js": "2.4.15"
   }
 }

test/fixtures/bin/6to5/stdin --filename/stderr.txt

@@ -1 +1 @@
-SyntaxError: test.js: Unexpected character '@'
+SyntaxError: test.js: Unexpected character '#'

test/fixtures/bin/6to5/stdin --filename/stdin.txt

@@ -1,3 +1,3 @@
 arr.map(x => {
-  $@!
+  $#!
 });

test/fixtures/transformation/errors/syntax/actual.js

@@ -1,3 +1,3 @@
 arr.map(function () {
-  return $@!@#;
+  return $#!;
 });

test/fixtures/transformation/errors/syntax/options.json

@@ -1,3 +1,3 @@
 {
-  "throws": "Unexpected character '@'"
+  "throws": "Unexpected character '#'"
 }

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

@@ -1,11 +1,6 @@
 "use strict";
 
 var _slice = Array.prototype.slice;
-var _classProps = function (child, staticProps, instanceProps) {
-  if (staticProps) Object.defineProperties(child, staticProps);
-  if (instanceProps) Object.defineProperties(child.prototype, instanceProps);
-};
-
 var _extends = function (child, parent) {
   child.prototype = Object.create(parent.prototype, {
     constructor: {
@@ -34,25 +29,17 @@ var Test = (function (Foo) {
 
   _extends(Test, Foo);
 
-  _classProps(Test, {
-    foo: {
-      writable: true,
-      value: 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: {
-      writable: true,
-      value: 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)));
+  };
 
   return Test;
 })(Foo);

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

@@ -1,10 +1,5 @@
 "use strict";
 
-var _classProps = function (child, staticProps, instanceProps) {
-  if (staticProps) Object.defineProperties(child, staticProps);
-  if (instanceProps) Object.defineProperties(child.prototype, instanceProps);
-};
-
 var _extends = function (child, parent) {
   child.prototype = Object.create(parent.prototype, {
     constructor: {
@@ -25,14 +20,9 @@ var Test = (function (Foo) {
 
   _extends(Test, Foo);
 
-  _classProps(Test, {
-    test: {
-      writable: true,
-      value: function () {
-        return Foo.wow.call(this);
-      }
-    }
-  });
+  Test.test = function () {
+    return Foo.wow.call(this);
+  };
 
   return Test;
 })(Foo);

test/fixtures/transformation/es6-classes/instance-method/expected.js

@@ -1,21 +1,11 @@
 "use strict";
 
-var _classProps = function (child, staticProps, instanceProps) {
-  if (staticProps) Object.defineProperties(child, staticProps);
-  if (instanceProps) Object.defineProperties(child.prototype, instanceProps);
-};
-
 var Test = (function () {
   var Test = function Test() {};
 
-  _classProps(Test, null, {
-    test: {
-      writable: true,
-      value: function () {
-        return 5 + 5;
-      }
-    }
-  });
+  Test.prototype.test = function () {
+    return 5 + 5;
+  };
 
   return Test;
 })();

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

@@ -1,10 +1,5 @@
 "use strict";
 
-var _classProps = function (child, staticProps, instanceProps) {
-  if (staticProps) Object.defineProperties(child, staticProps);
-  if (instanceProps) Object.defineProperties(child.prototype, instanceProps);
-};
-
 var BaseView = function BaseView() {
   this.autoRender = true;
 };
@@ -16,14 +11,9 @@ var BaseView = function () {
 var BaseView = (function () {
   var _class2 = function () {};
 
-  _classProps(_class2, null, {
-    foo: {
-      writable: true,
-      value: function () {
-        this.autoRender = true;
-      }
-    }
-  });
+  _class2.prototype.foo = function () {
+    this.autoRender = true;
+  };
 
   return _class2;
 })();

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

@@ -8,11 +8,9 @@ var _classProps = function (child, staticProps, instanceProps) {
 var A = (function () {
   var A = function A() {};
 
+  A.a = function () {};
+
   _classProps(A, {
-    a: {
-      writable: true,
-      value: function () {}
-    },
     b: {
       get: function () {},
       set: function (b) {}

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

@@ -1,5 +1,5 @@
 var obj = {
   [foobar]() {
-  return "foobar";
+    return "foobar";
   }
 };

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

@@ -4,5 +4,6 @@ var obj = (function (_obj) {
   _obj[foobar] = function () {
     return "foobar";
   };
+
   return _obj;
 })({});

test/fixtures/transformation/es6-let-scoping/loop-initializer-default/actual.js

@@ -0,0 +1,11 @@
+while (value) {
+  let foo;
+
+  if (bar) {
+    foo = [];
+  }
+
+  if (foo) {
+    doIt();
+  }
+}

test/fixtures/transformation/es6-let-scoping/loop-initializer-default/expected.js

@@ -0,0 +1,13 @@
+"use strict";
+
+while (value) {
+  var foo = undefined;
+
+  if (bar) {
+    foo = [];
+  }
+
+  if (foo) {
+    doIt();
+  }
+}

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

@@ -6,7 +6,9 @@ define(["exports"], function (exports) {
   exports["default"] = [];
   exports["default"] = foo;
   exports["default"] = function () {};
+
   exports["default"] = function () {};
+
   function foo() {}
   exports["default"] = foo;
   var Foo = function Foo() {};

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

@@ -6,7 +6,9 @@ module.exports = {};
 module.exports = [];
 module.exports = foo;
 module.exports = function () {};
+
 module.exports = function () {};
+
 function foo() {}
 var Foo = function Foo() {};
 

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

@@ -5,7 +5,9 @@ exports["default"] = {};
 exports["default"] = [];
 exports["default"] = foo;
 exports["default"] = function () {};
+
 exports["default"] = function () {};
+
 function foo() {}
 exports["default"] = foo;
 var Foo = function Foo() {};

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

@@ -12,7 +12,9 @@
   exports["default"] = [];
   exports["default"] = foo;
   exports["default"] = function () {};
+
   exports["default"] = function () {};
+
   function foo() {}
   exports["default"] = foo;
   var Foo = function Foo() {};

test/fixtures/transformation/playground/object-getter-memoization/actual.js

@@ -0,0 +1,19 @@
+class Foo {
+  memo bar() {
+    return complex();
+  }
+
+  memo [bar]() {
+    return complex();
+  }
+}
+
+var foo = {
+  memo bar() {
+    return complex();
+  },
+
+  memo [bar]() {
+    return complex();
+  }
+};

test/fixtures/transformation/playground/object-getter-memoization/expected.js

@@ -0,0 +1,53 @@
+"use strict";
+
+var _classProps = function (child, staticProps, instanceProps) {
+  if (staticProps) Object.defineProperties(child, staticProps);
+  if (instanceProps) Object.defineProperties(child.prototype, instanceProps);
+};
+
+var Foo = (function () {
+  var Foo = function Foo() {};
+
+  _classProps(Foo, null, (function (_ref) {
+    _ref[bar] = {
+      get: function () {
+        if (this._memoDone) return this._memo;
+        this._memoDone = true;
+        return this._memo = complex();
+      }
+    };
+    return _ref;
+  })({
+    bar: {
+      get: function () {
+        if (this._barDone) return this._bar;
+        this._barDone = true;
+        return this._bar = complex();
+      }
+    }
+  }));
+
+  return Foo;
+})();
+
+var foo = (function (_foo) {
+  _foo[bar] = function () {
+    if (this._memo2Done) return this._memo2;
+    this._memo2Done = true;
+    return this._memo2 = complex();
+  };
+
+  return _foo;
+})((function (_ref2) {
+  Object.defineProperties(_ref2, {
+    bar: {
+      get: function () {
+        if (this._barDone) return this._bar;
+        this._barDone = true;
+        return this._bar = complex();
+      }
+    }
+  });
+
+  return _ref2;
+})({}));