v2.3.1

System test adjustments

.jshintignore

@@ -1,3 +1,3 @@
 node_modules
 test
-lib/6to5/templates
+lib/6to5/transformation/templates

.npmignore

@@ -1,7 +1,7 @@
 node_modules
 *.log
 *.cache
-lib/6to5/templates
+lib/6to5/transformation/templates
 test
 benchmark
 Makefile

CHANGELOG.md

@@ -2,6 +2,38 @@
 
 Gaps between patch versions are faulty/broken releases.
 
+## 2.3.1
+
+ * Add `undefinedToVoid` optional transformer.
+ * Use `Object.defineProperty` for computed properties.
+
+## 2.3.0
+
+ * Upgrade `acorn-6to5`.
+ * Support circular references and hoist variable declarations in `system` module formatter.
+ * Add optional transformers, including a new `coreAliasing` transformer that aliases native ES6 static properties to their `core-js` equivalent.
+
+## 2.2.0
+
+ * Make `system` module formatter modules anonymous by default.
+ * Fix duplicate comments being output, breaking code.
+
+## 2.1.0
+
+ * Add `cache` option to register hook.
+ * Update `core-js`.
+ * Fix starting newline not being added on case statements.
+ * Fix destructuring `VariableDeclaration`s not inside `BlockStatement`s and `Program`.
+
+## 2.0.4
+
+ * Avoid being greedy when destructuring array iterables.
+
+## 2.0.3
+
+ * Hoist function declarations in system module formatter for circular references.
+ * Hoist default function declarations in umd and amd module formatters for circular references.
+
 ## 2.0.2
 
  * Inherit comments in `for-of` transformer.

Makefile

@@ -21,8 +21,7 @@ lint:
 test-clean:
 	rm -rf test/tmp
 
-test:
-	make lint
+test: lint
 	$(MOCHA_CMD)
 	make test-clean
 
@@ -33,8 +32,7 @@ test-cov:
 test-spec:
 	node $(ISTANBUL_CMD) $(MOCHA_CMD) -- --reporter spec
 
-test-travis:
-	make test-spec
+test-travis: test-spec
 	if test -n "$$CODECLIMATE_REPO_TOKEN"; then codeclimate < coverage/lcov.info; fi
 
 test-browser:

bin/6to5-runtime

@@ -1,4 +1,4 @@
 #!/usr/bin/env node
 
-var runtime = require("../lib/6to5/runtime");
+var runtime = require("../lib/6to5/runtime-generator");
 console.log(runtime(process.argv[2]));

bin/6to5/index.js

@@ -17,18 +17,28 @@ commander.option("-p, --playground", "Enable playground support");
 commander.option("-m, --modules [modules]", "Module formatter type to use [common]", "common");
 commander.option("-w, --whitelist [whitelist]", "Whitelist of transformers to ONLY use", util.list);
 commander.option("-b, --blacklist [blacklist]", "Blacklist of transformers to NOT use", util.list);
+commander.option("-i, --optional [list]", "List of optional transformers to enable", util.list);
 commander.option("-o, --out-file [out]", "Compile all input files into a single file");
 commander.option("-d, --out-dir [out]", "Compile an input directory of modules into an output directory");
 commander.option("-c, --remove-comments", "Remove comments from the compiled code", false);
-commander.option("-a, --amd-module-ids", "Insert module id in AMD modules", false);
+commander.option("-a, --amd-module-ids", "Insert module id in AMD modules", false); // todo: remove in 3.0.0
+commander.option("-m, --module-ids", "Insert module id in modules", false);
 
 commander.on("--help", function(){
   var outKeys = function (title, obj) {
     console.log("  " + title + ":");
     console.log();
 
+    var hasOptional = true;
+
     _.each(_.keys(obj).sort(), function (key) {
       if (key[0] === "_") return;
+
+      if (obj[key].optional) {
+        hasOptional = true;
+        key = "[" + key + "]";
+      }
+
       console.log("    - " + key);
     });
 
@@ -89,12 +99,13 @@ if (errors.length) {
 
 exports.opts = {
   sourceMapName: commander.outFile,
-  amdModuleIds:  commander.amdModuleIds,
   experimental:  commander.experimental,
   playground:    commander.playground,
+  moduleIds:     commander.amdModuleIds || commander.moduleIds,
   blacklist:     commander.blacklist,
   whitelist:     commander.whitelist,
   sourceMap:     commander.sourceMaps || commander.sourceMapsInline,
+  optional:      commander.optional,
   comments:      !commander.removeComments,
   runtime:       commander.runtime,
   modules:       commander.modules

doc/usage.md

@@ -152,10 +152,10 @@ result.ast;
   // Default: `sourceRoot` option.
   moduleRoot: "my-app",
 
-  // If truthy, insert an explicit id for each defined AMD module.
-  // By default, AMD modules are anonymous.
+  // If truthy, insert an explicit id for each defined AMD/System module.
+  // By default, AMD/System modules are anonymous.
   // Default: false
-  amdModuleIds: true,
+  moduleIds: true,
 
   // Optionally replace all 6to5 helper declarations with a referenece to this
   // variable. If set to `true` then the default namespace is used "to5Runtime".
@@ -250,6 +250,10 @@ require("6to5/register")({
 
   // This will remove the currently hooked extensions of .es6 and .js so you'll
   // have to add them back if you want them to be used again.
-  extensions: [".js", ".es6"]
+  extensions: [".js", ".es6"],
+
+  // Enables `roadrunner` cache that will save to a `.roadrunner.json` file in your cwd
+  // Do not check this into git as it's user-specific
+  cache: true
 });
 ```

lib/6to5/file.js

@@ -10,9 +10,10 @@ var t         = require("./types");
 var _         = require("lodash");
 
 function File(opts) {
-  this.opts = File.normaliseOptions(opts);
-  this.uids = {};
-  this.ast  = {};
+  this.opts         = File.normaliseOptions(opts);
+  this.transformers = this.getTransformers();
+  this.uids         = {};
+  this.ast          = {};
 }
 
 File.declarations = [
@@ -22,9 +23,11 @@ File.declarations = [
   "tagged-template-literal",
   "interop-require",
   "to-array",
+  "sliced-to-array",
   "object-without-properties",
   "has-own",
-  "slice"
+  "slice",
+  "define-property"
 ];
 
 File.normaliseOptions = function (opts) {
@@ -34,9 +37,11 @@ File.normaliseOptions = function (opts) {
     experimental: false,
     playground:   false,
     whitespace:   true,
+    moduleIds:    opts.amdModuleIds || false,
     blacklist:    [],
     whitelist:    [],
     sourceMap:    false,
+    optional:     [],
     comments:     true,
     filename:     "unknown",
     modules:      "common",
@@ -78,17 +83,37 @@ File.normaliseOptions = function (opts) {
 
   transform._ensureTransformerNames("blacklist", opts.blacklist);
   transform._ensureTransformerNames("whitelist", opts.whitelist);
+  transform._ensureTransformerNames("optional", opts.optional);
 
   return opts;
 };
 
-File.prototype.toArray = function (node) {
+File.prototype.getTransformers = function () {
+  var file = this;
+  var transformers = [];
+
+  _.each(transform.transformers, function (transformer) {
+    if (transformer.canRun(file)) {
+      transformers.push(transformer);
+    }
+  });
+
+  return transformers;
+};
+
+File.prototype.toArray = function (node, i) {
   if (t.isArrayExpression(node)) {
     return node;
   } else if (t.isIdentifier(node) && node.name === "arguments") {
     return t.callExpression(t.memberExpression(this.addDeclaration("slice"), t.identifier("call")), [node]);
   } else {
-    return t.callExpression(this.addDeclaration("to-array"), [node]);
+    var declarationName = "to-array";
+    var args = [node];
+    if (i) {
+      args.push(t.literal(i));
+      declarationName = "sliced-to-array";
+    }
+    return t.callExpression(this.addDeclaration(declarationName), args);
   }
 };
 
@@ -174,15 +199,25 @@ File.prototype.parse = function (code) {
 };
 
 File.prototype.transform = function (ast) {
+  var self = this;
+
   this.ast = ast;
   this.scope = new Scope(ast.program);
   this.moduleFormatter = this.getModuleFormatter(this.opts.modules);
 
-  var self = this;
+  var astRun = function (key) {
+    _.each(self.transformers, function (transformer) {
+      transformer.astRun(self, key);
+    });
+  };
 
-  _.each(transform.transformers, function (transformer) {
+  astRun("enter");
+
+  _.each(this.transformers, function (transformer) {
     transformer.transform(self);
   });
+
+  astRun("exit");
 };
 
 File.prototype.generate = function () {

lib/6to5/generation/generator.js

@@ -115,6 +115,7 @@ CodeGenerator.prototype.print = function (node, parent, opts) {
   if (!node) return "";
 
   var self = this;
+
   opts = opts || {};
 
   var newline = function (leading) {
@@ -170,7 +171,7 @@ CodeGenerator.prototype.print = function (node, parent, opts) {
 
     this.printTrailingComments(node, parent);
   } else {
-    throw new ReferenceError("unknown node " + node.type);
+    throw new ReferenceError("unknown node of type " + JSON.stringify(node.type) + " with constructor " + JSON.stringify(node && node.constructor.name));
   }
 };
 

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

@@ -146,7 +146,7 @@ exports.SwitchCase = function (node, print) {
     this.push("default:");
   }
 
-  this.space();
+  this.newline();
   print.sequence(node.consequent, { indent: true });
 };
 

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/index.js

@@ -3,11 +3,9 @@ var util      = require("./util");
 var fs        = require("fs");
 var _         = require("lodash");
 
-exports.Transformer = require("./transformation/transformer");
-
 exports.types = require("./types");
 
-exports.runtime = require("./runtime");
+exports.runtime = require("./runtime-generator");
 
 exports.register = function (opts) {
   var register = require("./register");

lib/6to5/register.js

@@ -1,6 +1,7 @@
 require("./polyfill");
 
 var sourceMapSupport = require("source-map-support");
+var roadrunner       = require("roadrunner");
 var util             = require("./util");
 var to5              = require("./index");
 var fs               = require("fs");
@@ -38,15 +39,22 @@ var blacklistTest = function (transformer, code) {
 };
 
 blacklistTest("arrayComprehension", "var foo = [for (foo of bar) foo * foo];");
-//blacklistTest("generatorComprehension", "");
+blacklistTest("generatorComprehension", "var foo = (for (foo of bar) foo * foo)");
 blacklistTest("arrowFunctions", "var foo = x => x * x;");
 blacklistTest("classes", "class Foo {}");
 blacklistTest("computedPropertyNames", "var foo = { [foo]: bar };");
-//blacklistTest("constants", "const foo = 0;");
+blacklistTest("constants", function () {
+  try {
+    new Function("const foo = 'foo';\nfoo = 'wow';");
+  } catch (err) {
+    return; // constants are supported
+  }
+  throw new SyntaxError;
+});
 blacklistTest("defaultParamaters", "var foo = function (bar = 0) {};");
 blacklistTest("destructuring", "var { x, y } = { x: 0, y: 0 };");
 blacklistTest("forOf", "for (var foo of bar) {}");
-blacklistTest("generators", "function* foo() {}");
+blacklistTest("generators", "function* foo() {}\nasync function bar() {}"); // generators/async functions delegated to same transformer
 blacklistTest("letScoping", "let foo = 0;");
 blacklistTest("modules", 'import foo from "from";');
 blacklistTest("propertyMethodAssignment", "{ get foo() {} }");
@@ -130,6 +138,11 @@ module.exports = function (opts) {
 
   if (opts.cache) cache = opts.cache;
   if (opts.cache === false) cache = null;
+  if (opts.cache === true) {
+    roadrunner.load();
+    roadrunner.setup();
+    cache = roadrunner.get("6to5");
+  }
 
   _.extend(transformOpts, opts);
 };

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

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

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

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

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

@@ -124,9 +124,9 @@ DefaultFormatter.prototype._pushStatement = function (ref, nodes) {
   return ref;
 };
 
-DefaultFormatter.prototype._hoistExport = function (declar, assign) {
+DefaultFormatter.prototype._hoistExport = function (declar, assign, priority) {
   if (t.isFunctionDeclaration(declar)) {
-    assign._blockHoist = true;
+    assign._blockHoist = priority || 2;
   }
 
   return assign;
@@ -139,17 +139,18 @@ DefaultFormatter.prototype._exportSpecifier = function (getRef, specifier, node,
   if (node.source) {
     if (t.isExportBatchSpecifier(specifier)) {
       // export * from "foo";
-      nodes.push(this._exportsWildcard(getRef()));
+      nodes.push(this._exportsWildcard(getRef(), node));
     } else {
       // export { foo } from "test";
       nodes.push(this._exportsAssign(
         t.getSpecifierName(specifier),
-        t.memberExpression(getRef(), specifier.id)
+        t.memberExpression(getRef(), specifier.id),
+        node
       ));
     }
   } else {
     // export { foo };
-    nodes.push(this._exportsAssign(t.getSpecifierName(specifier), specifier.id));
+    nodes.push(this._exportsAssign(t.getSpecifierName(specifier), specifier.id, node));
   }
 };
 
@@ -169,30 +170,36 @@ DefaultFormatter.prototype._exportsAssign = function (id, init) {
 DefaultFormatter.prototype.exportDeclaration = function (node, nodes) {
   var declar = node.declaration;
 
+  var id = declar.id;
+
   if (node.default) {
-    nodes.push(
-      this._exportsAssign(t.identifier("default"), this._pushStatement(declar, nodes))
-    );
-  } else {
-    var assign;
+    id = t.identifier("default");
+  }
 
-    if (t.isVariableDeclaration(declar)) {
-      for (var i in declar.declarations) {
-        var decl = declar.declarations[i];
+  var assign;
 
-        decl.init = this._exportsAssign(decl.id, decl.init).expression;
+  if (t.isVariableDeclaration(declar)) {
+    for (var i in declar.declarations) {
+      var decl = declar.declarations[i];
 
-        var newDeclar = t.variableDeclaration(declar.kind, [decl]);
-        if (i === "0") t.inherits(newDeclar, declar);
-        nodes.push(newDeclar);
-      }
-    } else {
-      assign = this._exportsAssign(declar.id, declar.id);
+      decl.init = this._exportsAssign(decl.id, decl.init, node).expression;
 
-      nodes.push(t.toStatement(declar));
-      nodes.push(assign);
-
-      this._hoistExport(declar, assign);
+      var newDeclar = t.variableDeclaration(declar.kind, [decl]);
+      if (i === "0") t.inherits(newDeclar, declar);
+      nodes.push(newDeclar);
     }
+  } else {
+    var ref = declar;
+
+    if (t.isFunctionDeclaration(declar) || t.isClassDeclaration(declar)) {
+      ref = declar.id;
+      nodes.push(declar);
+    }
+
+    assign = this._exportsAssign(id, ref, node);
+
+    nodes.push(assign);
+
+    this._hoistExport(declar, assign);
   }
 };

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

@@ -55,7 +55,7 @@ AMDFormatter.prototype.transform = function (ast) {
  */
 
 AMDFormatter.prototype.getModuleName = function () {
-  if (this.file.opts.amdModuleIds) {
+  if (this.file.opts.moduleIds) {
     return DefaultFormatter.prototype.getModuleName.apply(this, arguments);
   } else {
     return null;

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));
-  } 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/modules/system.js

@@ -1,26 +1,27 @@
 module.exports = SystemFormatter;
 
-var DefaultFormatter = require("./_default");
-var AMDFormatter     = require("./amd");
-var util             = require("../../util");
-var t                = require("../../types");
-var _                = require("lodash");
+var AMDFormatter = require("./amd");
+var traverse     = require("../../traverse");
+var util         = require("../../util");
+var t            = require("../../types");
+var _            = require("lodash");
 
 function SystemFormatter(file) {
   this.exportIdentifier  = file.generateUidIdentifier("export");
   this.noInteropRequire = true;
 
   AMDFormatter.apply(this, arguments);
-
-  this.moduleNameLiteral = t.literal(this.getModuleName());
 }
 
 util.inherits(SystemFormatter, AMDFormatter);
 
-SystemFormatter.prototype.getModuleName = DefaultFormatter.prototype.getModuleName;
+SystemFormatter.prototype._addImportSource = function (node, exportNode) {
+  node._importSource = exportNode.source && exportNode.source.value;
+  return node;
+};
 
-SystemFormatter.prototype._exportsWildcard = function (objectIdentifier) {
-  var leftIdentifier = t.identifier("i");
+SystemFormatter.prototype._exportsWildcard = function (objectIdentifier, node) {
+  var leftIdentifier = this.file.generateUidIdentifier("key");
   var valIdentifier  = t.memberExpression(objectIdentifier, leftIdentifier, true);
 
   var left = t.variableDeclaration("var", [
@@ -33,11 +34,12 @@ SystemFormatter.prototype._exportsWildcard = function (objectIdentifier) {
     this.buildExportCall(leftIdentifier, valIdentifier)
   ]);
 
-  return t.forInStatement(left, right, block);
+  return this._addImportSource(t.forInStatement(left, right, block), node);
 };
 
-SystemFormatter.prototype._exportsAssign = function (id, init) {
-  return this.buildExportCall(t.literal(id.name), init, true);
+SystemFormatter.prototype._exportsAssign = function (id, init, node) {
+  var call = this.buildExportCall(t.literal(id.name), init, true);
+  return this._addImportSource(call, node);
 };
 
 SystemFormatter.prototype.remapExportAssignment = function (node) {
@@ -53,33 +55,120 @@ SystemFormatter.prototype.buildExportCall = function (id, init, isStatement) {
   }
 };
 
-SystemFormatter.prototype.buildRunnerSetters = function () {
-  return t.arrayExpression(_.map(this.ids, function (uid) {
-    var moduleIdentifier = t.identifier("m");
+SystemFormatter.prototype.importSpecifier = function (specifier, node, nodes) {
+  AMDFormatter.prototype.importSpecifier.apply(this, arguments);
+  this._addImportSource(_.last(nodes), node);
+};
 
-    return t.functionExpression(null, [moduleIdentifier], t.blockStatement([
-      t.assignmentExpression("=", uid, moduleIdentifier)
-    ]));
+SystemFormatter.prototype.buildRunnerSetters = function (block, hoistDeclarators) {
+  return t.arrayExpression(_.map(this.ids, function (uid, source) {
+    var nodes = [];
+
+    traverse(block, {
+      enter: function (node) {
+        if (node._importSource === source) {
+          if (t.isVariableDeclaration(node)) {
+            _.each(node.declarations, function (declar) {
+              hoistDeclarators.push(t.variableDeclarator(declar.id));
+              nodes.push(t.expressionStatement(
+                t.assignmentExpression("=", declar.id, declar.init)
+              ));
+            });
+          } else {
+            nodes.push(node);
+          }
+
+          this.remove();
+        }
+      }
+    });
+
+    return t.functionExpression(null, [uid], t.blockStatement(nodes));
   }));
 };
 
 SystemFormatter.prototype.transform = function (ast) {
   var program = ast.program;
 
+  var hoistDeclarators = [];
+  var moduleName = this.getModuleName();
+  var moduleNameLiteral = t.literal(moduleName);
+
+  var block = t.blockStatement(program.body);
+
   var runner = util.template("system", {
-    MODULE_NAME: this.moduleNameLiteral,
+    MODULE_NAME: moduleNameLiteral,
     MODULE_DEPENDENCIES: t.arrayExpression(this.buildDependencyLiterals()),
     EXPORT_IDENTIFIER: this.exportIdentifier,
-    SETTERS: this.buildRunnerSetters(),
-    EXECUTE: t.functionExpression(null, [], t.blockStatement(program.body))
+    SETTERS: this.buildRunnerSetters(block, hoistDeclarators),
+    EXECUTE: t.functionExpression(null, [], block)
   }, true);
 
-  if (!_.isEmpty(this.ids)) {
-    var handlerBody = runner.expression.arguments[2].body.body;
-    handlerBody.unshift(t.variableDeclaration("var", _.map(this.ids, function (uid) {
-      return t.variableDeclarator(uid);
-    })));
+  var handlerBody = runner.expression.arguments[2].body.body;
+  if (!moduleName) runner.expression.arguments.shift();
+
+  var returnStatement = handlerBody.pop();
+
+  // hoist up all variable declarations
+  traverse(block, {
+    enter: function (node, parent, scope) {
+      if (t.isFunction(node)) {
+        // nothing inside is accessible
+        return this.stop();
+      }
+
+      if (t.isVariableDeclaration(node)) {
+        if (node.kind !== "var" && !t.isProgram(parent)) { // let, const
+          // can't be accessed
+          return;
+        }
+
+        var nodes = [];
+
+        _.each(node.declarations, function (declar) {
+          hoistDeclarators.push(t.variableDeclarator(declar.id));
+          if (declar.init) {
+            // no initializer so we can just hoist it as-is
+            var assign = t.expressionStatement(t.assignmentExpression("=", declar.id, declar.init));
+            nodes.push(assign);
+          }
+        });
+
+        // for (var i in test)
+        // for (var i = 0;;)
+        if (t.isFor(parent)) {
+          if (parent.left === node) {
+            return node.declarations[0].id;
+          }
+
+          if (parent.init === node) {
+            return t.toSequenceExpression(nodes, scope);
+          }
+        }
+
+        return nodes;
+      }
+    }
+  });
+  if (hoistDeclarators.length) {
+    var hoistDeclar = t.variableDeclaration("var", hoistDeclarators);
+    hoistDeclar._blockHoist = true;
+    handlerBody.unshift(hoistDeclar);
   }
 
+  // hoist up function declarations for circular references
+  traverse(block, {
+    enter: function (node) {
+      if (t.isFunction(node)) this.stop();
+
+      if (t.isFunctionDeclaration(node) || node._blockHoist) {
+        handlerBody.push(node);
+        this.remove();
+      }
+    }
+  });
+
+  handlerBody.push(returnStatement);
+
   program.body = [runner];
 };

lib/6to5/transformation/templates/common-export-default-assign.js

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

lib/6to5/transformation/templates/corejs-iterator.js

@@ -0,0 +1 @@
+CORE_ID.$for.getIterator(VALUE);

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/sliced-to-array.js

@@ -0,0 +1,12 @@
+(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);
+      if (i && _arr.length === i) break;
+    }
+    return _arr;
+  }
+});

lib/6to5/transformation/transform.js

@@ -80,6 +80,9 @@ _.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"),

lib/6to5/transformation/transformer.js

@@ -5,9 +5,11 @@ var t        = require("../types");
 var _        = require("lodash");
 
 function Transformer(key, transformer, opts) {
-  this.transformer = Transformer.normalise(transformer);
-  this.opts        = opts || {};
-  this.key         = key;
+  this.experimental = !!transformer.experimental;
+  this.transformer  = Transformer.normalise(transformer);
+  this.optional     = !!transformer.optional;
+  this.opts         = opts || {};
+  this.key          = key;
 }
 
 Transformer.normalise = function (transformer) {
@@ -16,8 +18,13 @@ Transformer.normalise = function (transformer) {
   }
 
   _.each(transformer, function (fns, type) {
+    // hidden property
     if (type[0] === "_") return;
+
     if (_.isFunction(fns)) fns = { enter: fns };
+
+    if (!_.isObject(fns)) return;
+
     transformer[type] = fns;
 
     var aliases = t.FLIPPED_ALIAS_KEYS[type];
@@ -41,13 +48,9 @@ Transformer.prototype.astRun = function (file, key) {
 };
 
 Transformer.prototype.transform = function (file) {
-  if (!this.canRun(file)) return;
-
   var transformer = this.transformer;
   var ast         = file.ast;
 
-  this.astRun(file, "enter");
-
   var build = function (exit) {
     return function (node, parent, scope) {
       var fns = transformer[node.type];
@@ -61,25 +64,30 @@ Transformer.prototype.transform = function (file) {
     };
   };
 
+  this.astRun(file, "before");
+
   traverse(ast, {
     enter: build(),
     exit:  build(true)
   });
 
-  this.astRun(file, "exit");
+  this.astRun(file, "after");
 };
 
 Transformer.prototype.canRun = function (file) {
   var opts = file.opts;
   var key  = this.key;
+  if (key[0] === "_") return true;
 
   var blacklist = opts.blacklist;
   if (blacklist.length && _.contains(blacklist, key)) return false;
 
-  if (key[0] !== "_") {
-    var whitelist = opts.whitelist;
-    if (whitelist.length && !_.contains(whitelist, key)) return false;
-  }
+  var whitelist = opts.whitelist;
+  if (whitelist.length && !_.contains(whitelist, key)) return false;
+
+  if (this.optional && !_.contains(opts.optional, key)) return false;
+
+  if (this.experimental && !opts.experimental) return false;
 
   return true;
 };

lib/6to5/transformation/transformers/_alias-functions.js

@@ -20,7 +20,7 @@ var go = function (getBody, node, file, scope) {
       if (!node._aliasFunction) {
         if (t.isFunction(node)) {
           // stop traversal of this node as it'll be hit again by this transformer
-          return false;
+          return this.stop();
         } else {
           return;
         }
@@ -30,10 +30,10 @@ var go = function (getBody, node, file, scope) {
       traverse(node, {
         enter: function (node, parent) {
           if (t.isFunction(node) && !node._aliasFunction) {
-            return false;
+            return this.stop();
           }
 
-          if (node._ignoreAliasFunctions) return false;
+          if (node._ignoreAliasFunctions) return this.stop();
 
           var getId;
 
@@ -49,7 +49,7 @@ var go = function (getBody, node, file, scope) {
         }
       });
 
-      return false;
+      return this.stop();
     }
   });
 

lib/6to5/transformation/transformers/_block-hoist.js

@@ -1,17 +1,29 @@
+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 unshift = [];
+    var hasChange = false;
+    for (var i in node.body) {
+      var bodyNode = node.body[i];
+      if (bodyNode && bodyNode._blockHoist != null) hasChange = true;
+    }
+    if (!hasChange) return;
 
-    node.body = node.body.filter(function (bodyNode) {
-      if (bodyNode._blockHoist) {
-        unshift.push(bodyNode);
-        return false;
-      } else {
-        return true;
-      }
+    var nodePriorities = _.groupBy(node.body, function (bodyNode) {
+      var priority = bodyNode._blockHoist;
+      if (priority == null) priority = 1;
+      if (priority === true) priority = 2;
+      return priority;
     });
 
-    node.body = unshift.concat(node.body);
+    node.body = _.flatten(_.values(nodePriorities).reverse());
   }
 };

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

@@ -20,14 +20,21 @@ exports.ObjectExpression = function (node, parent, file) {
 
   if (!hasAny) return;
 
-  var objId = util.getUid(parent, file);
+  if (node.properties.length) {
+    var objId = util.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

@@ -153,7 +153,7 @@ Class.prototype.buildBody = function () {
     }
   }
 
-  if (!this.hasConstructor && superName) {
+  if (!this.hasConstructor && superName && !t.isFalsyExpression(superName)) {
     constructor.body.body.push(util.template("class-super-constructor-call", {
       SUPER_NAME: superName
     }, true));

lib/6to5/transformation/transformers/es6-computed-property-names.js

@@ -3,45 +3,95 @@ 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 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

@@ -61,13 +61,27 @@ var pushObjectPattern = function (opts, nodes, pattern, parentId) {
 };
 
 var pushArrayPattern = function (opts, nodes, pattern, parentId) {
+  if (!pattern.elements) return;
+
+  var i;
+
+  var hasSpreadElement = false;
+  for (i in pattern.elements) {
+    if (t.isSpreadElement(pattern.elements[i])) {
+      hasSpreadElement = true;
+      break;
+    }
+  }
+
+  var toArray = opts.file.toArray(parentId, !hasSpreadElement && pattern.elements.length);
+
   var _parentId = opts.file.generateUidIdentifier("ref", opts.scope);
   nodes.push(t.variableDeclaration("var", [
-    t.variableDeclarator(_parentId, opts.file.toArray(parentId))
+    t.variableDeclarator(_parentId, toArray)
   ]));
   parentId = _parentId;
 
-  for (var i in pattern.elements) {
+  for (i in pattern.elements) {
     var elem = pattern.elements[i];
     if (!elem) continue;
 
@@ -254,6 +268,7 @@ exports.VariableDeclaration = function (node, parent, file, scope) {
   }
 
   if (!t.isProgram(parent) && !t.isBlockStatement(parent)) {
+    declar = null;
 
     for (i in nodes) {
       node = nodes[i];

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

@@ -1 +1,3 @@
-module.exports = require("regenerator").transform;
+exports.ast = {
+  before: require("regenerator").transform
+};

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

@@ -280,7 +280,7 @@ LetScoping.prototype.checkLoop = function () {
       var replace;
 
       if (t.isFunction(node) || t.isLoop(node)) {
-        return false;
+        return this.stop();
       }
 
       if (node && !node.label) {
@@ -329,7 +329,7 @@ LetScoping.prototype.hoistVarDeclarations = function () {
       } else if (isVar(node, parent)) {
         return self.pushDeclar(node).map(t.expressionStatement);
       } else if (t.isFunction(node)) {
-        return false;
+        return this.stop();
       }
     }
   });
@@ -388,9 +388,9 @@ LetScoping.prototype.getLetReferences = function () {
           }
         });
 
-        return false;
+        return this.stop();
       } else if (t.isLoop(node)) {
-        return false;
+        return this.stop();
       }
     }
   });

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

@@ -1,26 +1,16 @@
 var t = require("../../types");
 
-var inheritsComments = function (node, nodes) {
-  if (nodes.length) {
-    t.inheritsComments(nodes[0], node);
-  }
-};
-
 exports.ImportDeclaration = function (node, parent, file) {
   var nodes = [];
 
   if (node.specifiers.length) {
-    if (!file.moduleFormatter.importSpecifier) return;
     for (var i in node.specifiers) {
       file.moduleFormatter.importSpecifier(node.specifiers[i], node, nodes, parent);
     }
   } else {
-    if (!file.moduleFormatter.importDeclaration) return;
     file.moduleFormatter.importDeclaration(node, nodes, parent);
   }
 
-  inheritsComments(node, nodes);
-
   return nodes;
 };
 
@@ -35,16 +25,12 @@ exports.ExportDeclaration = function (node, parent, file) {
       declar.init = declar.init || t.identifier("undefined");
     }
 
-    if (!file.moduleFormatter.exportDeclaration) return;
     file.moduleFormatter.exportDeclaration(node, nodes, parent);
   } else {
-    if (!file.moduleFormatter.exportSpecifier) return;
     for (var i in node.specifiers) {
       file.moduleFormatter.exportSpecifier(node.specifiers[i], node, nodes, parent);
     }
   }
 
-  inheritsComments(node, nodes);
-
   return nodes;
 };

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

@@ -3,6 +3,8 @@
 var util = require("../../util");
 var t    = require("../../types");
 
+exports.experimental = true;
+
 var container = function (parent, call, ret) {
   if (t.isExpressionStatement(parent)) {
     // we don't need to worry about return values

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

@@ -1,6 +1,8 @@
 var util = require("../../util");
 var t    = require("../../types");
 
+exports.experimental = true;
+
 var single = function (node, file) {
   var block = node.blocks[0];
 

lib/6to5/transformation/transformers/es7-exponentiation-operator.js

@@ -1,5 +1,7 @@
 // https://github.com/rwaldron/exponentiation-operator
 
+exports.experimental = true;
+
 var t = require("../../types");
 var pow = t.memberExpression(t.identifier("Math"), t.identifier("pow"));
 

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

@@ -1,6 +1,8 @@
 var arrayComprehension = require("./es7-array-comprehension");
 var t                  = require("../../types");
 
+exports.experimental = true;
+
 exports.ComprehensionExpression = function (node) {
   if (!node.generator) return;
 

lib/6to5/transformation/transformers/es7-object-spread.js

@@ -2,6 +2,8 @@
 
 var t = require("../../types");
 
+exports.experimental = true;
+
 exports.ObjectExpression = function (node) {
   var hasSpread = false;
   var i;

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

@@ -0,0 +1,55 @@
+var traverse = require("../../traverse");
+var util     = require("../../util");
+var core     = require("core-js/library");
+var t        = require("../../types");
+var _        = require("lodash");
+
+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);
+  },
+
+  exit: function (ast, file) {
+    traverse(ast, {
+      enter: function (node, parent) {
+        var prop;
+
+        if (t.isMemberExpression(node) && t.isReferenced(node, parent)) {
+          // Array.from -> _core.Array.from
+          var obj = node.object;
+          prop = node.property;
+
+          if (!t.isReferenced(obj, node)) return;
+
+          var coreHasObject = obj.name !== "_" && _.has(core, obj.name);
+          if (coreHasObject && _.has(core[obj.name], prop.name)) {
+            this.stop();
+            return t.memberExpression(file._coreId, node);
+          }
+        } else if (t.isCallExpression(node)) {
+          // arr[Symbol.iterator]() -> _core.$for.getIterator(arr)
+
+          if (node.arguments.length) return;
+
+          var callee = node.callee;
+          if (!t.isMemberExpression(callee)) return;
+          if (!callee.computed) return;
+
+          prop = callee.property;
+          if (!t.isIdentifier(prop.object, { name: "Symbol" })) return;
+          if (!t.isIdentifier(prop.property, { name: "iterator" })) return;
+
+          return util.template("corejs-iterator", {
+            CORE_ID: file._coreId,
+            VALUE:   callee.object
+          });
+        }
+      }
+    });
+  }
+};

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-object-getter-memoization.js

@@ -2,38 +2,30 @@ var traverse = require("../../traverse");
 var t        = require("../../types");
 
 exports.Property =
-exports.MethodDefinition = function (node, parent, file, scope) {
+exports.MethodDefinition = function (node, parent, file) {
   if (node.kind !== "memo") return;
   node.kind = "get";
 
   var value = node.value;
   t.ensureBlock(value);
 
-  var body  = value.body.body;
-  var key   = node.key;
+  var key = node.key;
 
   if (t.isIdentifier(key) && !node.computed) {
-    key = "_" + key.name;
-  } else {
-    key = file.generateUid("memo", scope);
+    key = t.literal(key.name);
   }
 
-  var memoId = t.memberExpression(t.thisExpression(), t.identifier(key));
-  var doneId = t.memberExpression(t.thisExpression(), t.identifier(key + "Done"));
-
   traverse(value, {
     enter: function (node) {
       if (t.isFunction(node)) return;
 
       if (t.isReturnStatement(node) && node.argument) {
-        node.argument = t.assignmentExpression("=", memoId, node.argument);
+        node.argument = t.memberExpression(t.callExpression(file.addDeclaration("define-property"), [
+          t.thisExpression(),
+          key,
+          node.argument
+        ]), key, true);
       }
     }
   });
-
-  // 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/transformation/transformers/use-strict.js

@@ -1,12 +1,14 @@
 var t = require("../../types");
 
-module.exports = function (ast) {
-  var body = ast.program.body;
-  var first = body[0];
+exports.ast = {
+  exit: function (ast) {
+    var body = ast.program.body;
+    var first = body[0];
 
-  var noStrict = !first || !t.isExpressionStatement(first) || !t.isLiteral(first.expression) || first.expression.value !== "use strict";
+    var noStrict = !first || !t.isExpressionStatement(first) || !t.isLiteral(first.expression) || first.expression.value !== "use strict";
 
-  if (noStrict) {
-    body.unshift(t.expressionStatement(t.literal("use strict")));
+    if (noStrict) {
+      body.unshift(t.expressionStatement(t.literal("use strict")));
+    }
   }
 };

lib/6to5/traverse/index.js

@@ -39,22 +39,37 @@ function traverse(parent, opts, scope) {
       // replace node
       var maybeReplace = function (result) {
         if (result === false) return;
+        if (result == null) return;
 
-        if (result != null) {
-          updated = true;
-          node = obj[key] = result;
+        var isArray = _.isArray(result);
 
-          if (_.isArray(result) && _.contains(t.STATEMENT_OR_BLOCK_KEYS, key) && !t.isBlockStatement(obj)) {
-            t.ensureBlock(obj, key);
-          }
+        // inherit comments from original node to the first replacement node
+        var inheritTo = result;
+        if (isArray) inheritTo = result[0];
+        if (inheritTo) t.inheritsComments(inheritTo, node);
+
+        // replace the node
+        node = obj[key] = result;
+        updated = true;
+
+        // we're replacing a statement or block node with an array of statements so we better
+        // ensure that it's a block
+        if (isArray && _.contains(t.STATEMENT_OR_BLOCK_KEYS, key) && !t.isBlockStatement(obj)) {
+          t.ensureBlock(obj, key);
         }
       };
 
-      var stop = false;
+      var stopped = false;
+      var removed = false;
 
       var context = {
         stop: function () {
-          stop = true;
+          stopped = true;
+        },
+
+        remove: function () {
+          this.stop();
+          removed = true;
         }
       };
 
@@ -67,8 +82,13 @@ function traverse(parent, opts, scope) {
         var result = opts.enter.call(context, node, parent, ourScope);
         maybeReplace(result);
 
+        if (removed) {
+          obj[key] = null;
+          updated = true;
+        }
+
         // stop iteration
-        if (stop || result === false) return;
+        if (stopped) return;
       }
 
       // traverse node
@@ -85,7 +105,9 @@ function traverse(parent, opts, scope) {
         handle(nodes, i);
       }
 
-      if (updated) parent[key] = _.flatten(parent[key]);
+      if (updated) {
+        parent[key] = _.flatten(parent[key]);
+      }
     } else {
       handle(parent, key);
     }
@@ -134,7 +156,7 @@ traverse.hasType = function (tree, type, blacklistTypes) {
     enter: function (node) {
       if (node.type === type) {
         has = true;
-        return false;
+        this.stop();
       }
     }
   });

lib/6to5/traverse/scope.js

@@ -93,7 +93,7 @@ Scope.prototype.getInfo = function () {
 
         // this block is a function so we'll stop since none of the variables
         // declared within are accessible
-        if (t.isFunction(node)) return false;
+        if (t.isFunction(node)) return this.stop();
 
         // function identifier doesn't belong to this scope
         if (block.id && node === block.id) return;

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

@@ -11,6 +11,8 @@
   "FunctionExpression":      ["id", "params", "body", "generator"],
   "Identifier":              ["name"],
   "IfStatement":             ["test", "consequent", "alternate"],
+  "ImportDeclaration":       ["specifiers", "source"],
+  "ImportSpecifier":         ["id", "name"],
   "Literal":                 ["value"],
   "LogicalExpression":       ["operator", "left", "right"],
   "MemberExpression":        ["object", "property", "computed"],

lib/6to5/types/index.js

@@ -74,6 +74,17 @@ addAssert("Expression", t.isExpression);
 
 //
 
+t.isFalsyExpression = function (node) {
+  if (t.isLiteral(node)) {
+    return !node.value;
+  } else if (t.isIdentifier(node)) {
+    return node.name === "undefined";
+  }
+  return false;
+};
+
+//
+
 t.toSequenceExpression = function (nodes, scope) {
   var exprs = [];
 
@@ -293,8 +304,9 @@ t.removeComments = function (child) {
 };
 
 t.inheritsComments = function (child, parent) {
-  child.leadingComments  = _.compact([].concat(child.leadingComments, parent.leadingComments));
-  child.trailingComments = _.compact([].concat(child.trailingComments, parent.trailingComments));
+  _.each(["leadingComments", "trailingComments"], function (key) {
+    child[key]  = _.uniq(_.compact([].concat(child[key], parent[key])));
+  });
   return child;
 };
 

lib/6to5/util.js

@@ -268,7 +268,7 @@ exports.parseTemplate = function (loc, code) {
 var loadTemplates = function () {
   var templates = {};
 
-  var templatesLoc = __dirname + "/templates";
+  var templatesLoc = __dirname + "/transformation/templates";
   if (!fs.existsSync(templatesLoc)) {
     throw new Error("no templates directory - this is most likely the " +
                     "result of a broken `npm publish`. Please report to " +

package.json

@@ -1,7 +1,7 @@
 {
   "name": "6to5",
   "description": "Turn ES6 code into readable vanilla ES5 with source maps",
-  "version": "2.0.2",
+  "version": "2.3.1",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://github.com/6to5/6to5",
   "repository": {
@@ -35,11 +35,11 @@
     "test": "make test"
   },
   "dependencies": {
-    "acorn-6to5": "0.9.1-16",
+    "acorn-6to5": "0.11.1-1",
     "ast-types": "~0.6.1",
     "chokidar": "0.11.1",
     "commander": "2.5.0",
-    "core-js": "^0.3.2",
+    "core-js": "^0.3.3",
     "estraverse": "1.8.0",
     "esutils": "1.1.6",
     "fs-readdir-recursive": "0.1.0",

test/fixtures/generation/harmony-edgecase/class-declaration/actual.js

@@ -2,8 +2,6 @@ class Test {
 }
 class Derived extends Super {
 }
-class Derived2 extends Super() {
-}
 class StaticMethods {
   static n1() {
   }

test/fixtures/generation/harmony-edgecase/class-declaration/expected.js

@@ -1,6 +1,5 @@
 class Test {}
 class Derived extends Super {}
-class Derived2 extends Super() {}
 class StaticMethods {
   static n1() {}
 

test/fixtures/generation/harmony-edgecase/class-expression/actual.js

@@ -1,6 +1,5 @@
 (class Test { });
 (class Derived extends Super { });
-(class Derived2 extends Super() { });
 (class StaticMethods {
   static n1() {
   }
@@ -54,4 +53,3 @@
   }
 });
 (class { });
-(class extends Super() { });

test/fixtures/generation/harmony-edgecase/class-expression/expected.js

@@ -1,6 +1,5 @@
 (class Test {});
 (class Derived extends Super {});
-(class Derived2 extends Super() {});
 (class StaticMethods {
   static n1() {}
 
@@ -38,4 +37,3 @@
   *[gen1]() {}
 });
 (class {});
-(class extends Super() {});

test/fixtures/generation/types/SwitchStatement-SwitchCase/expected.js

@@ -33,7 +33,10 @@ switch (foo) {
 }
 
 switch (foo) {
-  case "foo": foo();
-  case "bar": bar();
-  default: yay();
+  case "foo":
+    foo();
+  case "bar":
+    bar();
+  default:
+    yay();
 }

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/super-class-id-non-identifiers/actual.js

@@ -1,3 +0,0 @@
-class Q extends function () {} {
-
-}

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

@@ -1,23 +0,0 @@
-"use strict";
-
-var _inherits = function (child, parent) {
-  child.prototype = Object.create(parent && parent.prototype, {
-    constructor: {
-      value: child,
-      enumerable: false,
-      writable: true,
-      configurable: true
-    }
-  });
-  if (parent) child.__proto__ = parent;
-};
-
-var _QSuper = function () {};
-
-var Q = function Q() {
-  if (_QSuper) {
-    _QSuper.apply(this, arguments);
-  }
-};
-
-_inherits(Q, _QSuper);

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;
+})();