v5.1.0

ES7 trailing function commas

.gitignore

@@ -11,6 +11,7 @@ test/core/tmp
 coverage
 dist
 .package.json
+packages/babel-runtime/core-js
 packages/babel-runtime/helpers/*.js
 packages/babel-runtime/regenerator/*.js
 lib

CHANGELOG.md

@@ -13,6 +13,87 @@ _Note: Gaps between patch versions are faulty/broken releases._
 
 See [CHANGELOG - 6to5](CHANGELOG-6to5.md) for the pre-4.0.0 version changelog.
 
+## 5.1.0
+
+ * **Bug Fix**
+  * Fix super reference when using decorators.
+  * Don't do array unpack optimisation when member expressions are present.
+  * Add missing descriptors for undecorated class properties.
+  * Don't consider `arguments` and `eval` valid function names when doing function name inferrence.
+  * Fix scope tracking of constants in loop heads.
+  * Parse `AwaitExpression` as a unary instead of an assignment.
+  * Fix regex evaluation when attempting static evaluation.
+  * Don't emit tokens when doing a lookahead.
+ * **Internal**
+  * Upgrade `regenerator` to the latest and use my branch with the hope of eventually switching to vanilla regenerator.
+  * Add support for the replacement of for loop `init`s with statements.
+  * Upgrade dependencies.
+ * **Polish**
+  * When adding the scope IIFE when using default parameters, don't shadow the function expression, just `apply` `this` and `arguments` if necessary.
+  * Use path basename as non-default import fallback.
+ * **New Feature**
+  * Add [trailing function comma proposal](https://github.com/jeffmo/es-trailing-function-commas). Thanks [@AluisioASG](https://github.com/AluisioASG)!
+  * Add support for object literal decorators.
+
+## 5.0.12
+
+ * **Bug Fix**
+  * Fix incorrect remapping of module references inside of a function id redirection container.
+
+## 5.0.11
+
+ * **Bug Fix**
+  * Fix new `for...of` loops not properly inheriting their original loop.
+ * **Internal**
+  * Disable scope instance cache.
+ * **Polish**
+  * Allow comments in `.babelrc` JSON.
+
+## 5.0.9
+
+ * **Polish**
+  * Use `moduleId` for UMD global name if available.
+ * **Bug Fix**
+  * Fix UMD global `module` variable shadowing the `amd`/`common` `module` variable.
+  * Fix Flow param type annotation regression.
+  * Fix function name collision `toString` wrapper. Thanks [@alawatthe](https://github.com/alawatthe)!
+
+## 5.0.8
+
+ * **Bug Fix**
+  * Fix falsy static class properties not being writable.
+  * Fix block scoping collisions not properly detecting modules and function clashes.
+  * Skip `this` before `super` for derived constructors on functions.
+
+## 5.0.7
+
+ * **New Feature**
+  * Add `--ignore` and `--only` support to the CLI.
+ * **Bug Fix**
+  * Remove `HOMEPATH` environment variable from home resolution in `babel/register` cache.
+ * **Internal**
+  * Disable WIP path resolution introducing infinite recursion in some code examples.
+ * **Polish**
+  * Add live binding to CommonJS default imports.
+
+## 5.0.6
+
+ * **Bug Fix**
+  * Fix mangling of import references that collide with properties on `Object.prototype`.
+  * Fix duplicate declarations incorrectly being reported for `var`.
+
+## 5.0.5
+
+ * **Internal**
+  * Upgrade `core-js`.
+ * **Bug Fix**
+  * Fix arrays not being supported in `util.list`.
+
+## 5.0.4
+
+ * **Polish**
+  * Check for top level `breakConfig` in `resolveRc`.
+
 ## 5.0.3
 
  * **Bug Fix**

CONTRIBUTING.md

@@ -35,13 +35,13 @@ This is mostly overkill and you can limit the tests to a select few by directly
 running them with `mocha`:
 
 ```sh
-$ mocha test/transformation.js
+$ mocha test/core/transformation.js
 ```
 
 Use mocha's `--grep` option to run a subset of tests by name:
 
 ```sh
-$ mocha test/transformation.js --grep es7
+$ mocha test/core/transformation.js --grep es7
 ```
 
 #### Workflow

Makefile

@@ -109,9 +109,10 @@ publish-cli:
 	npm publish
 
 bootstrap:
+	npm list --global --depth 1 babel >/dev/null 2>&1 && npm uninstall -g babel || true
 	npm install
 	npm link
-	cd packages/babel-cli && npm install && npm link
+	cd packages/babel-cli && npm install && npm link && npm link babel-core
 	git submodule update --init
 	cd vendor/regenerator && npm install
 	cd vendor/compat-table && npm install object-assign

README.md

@@ -9,7 +9,7 @@
 </p>
 
 <p align="center">
-  For questions and support please visit the <a href="https://gitter.im/babel/babel">gitter room</a> or <a href="stackoverflow.com">StackOverflow</a>. The Babel issue tracker is <strong>exclusively</strong> for bug reports and future requests.
+  For questions and support please visit the <a href="https://gitter.im/babel/babel">gitter room</a> or <a href="http://stackoverflow.com/questions/tagged/babeljs">StackOverflow</a>. The Babel issue tracker is <strong>exclusively</strong> for bug reports and feature requests.
 </p>
 
 <p align="center">

package.json

@@ -1,7 +1,7 @@
 {
   "name": "babel-core",
   "description": "Turn ES6 code into readable vanilla ES5 with source maps",
-  "version": "5.0.3",
+  "version": "5.1.0",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
   "repository": "babel/babel",
@@ -29,44 +29,46 @@
   "dependencies": {
     "ast-types": "~0.7.0",
     "chalk": "^1.0.0",
-    "convert-source-map": "^0.5.0",
-    "core-js": "^0.8.0",
+    "convert-source-map": "^1.0.0",
+    "core-js": "^0.8.1",
     "debug": "^2.1.1",
     "detect-indent": "^3.0.0",
-    "estraverse": "^1.9.1",
-    "esutils": "^1.1.6",
+    "estraverse": "^3.0.0",
+    "esutils": "^2.0.0",
     "fs-readdir-recursive": "^0.1.0",
-    "globals": "^6.2.0",
+    "globals": "^6.4.0",
     "is-integer": "^1.0.4",
     "js-tokens": "1.0.0",
     "leven": "^1.0.1",
     "line-numbers": "0.2.0",
-    "lodash": "^3.2.0",
+    "lodash": "^3.6.0",
     "minimatch": "^2.0.3",
     "output-file-sync": "^1.1.0",
     "path-is-absolute": "^1.0.0",
     "private": "^0.1.6",
-    "regenerator-babel": "0.8.13-2",
+    "regenerator": "https://github.com/sebmck/regenerator/archive/block-hoist.tar.gz",
     "regexpu": "^1.1.2",
     "repeating": "^1.1.2",
     "shebang-regex": "^1.0.0",
     "slash": "^1.0.0",
     "source-map": "^0.4.0",
-    "source-map-support": "^0.2.9",
+    "source-map-support": "^0.2.10",
+    "strip-json-comments": "^1.0.2",
     "to-fast-properties": "^1.0.0",
-    "trim-right": "^1.0.0"
+    "trim-right": "^1.0.0",
+    "user-home": "^1.1.1"
   },
   "devDependencies": {
     "babel": "4.7.13",
-    "browserify": "^9.0.3",
-    "chai": "^2.0.0",
-    "eslint": "^0.15.1",
-    "babel-eslint": "^1.0.1",
+    "browserify": "^9.0.8",
+    "chai": "^2.2.0",
+    "eslint": "^0.18.0",
+    "babel-eslint": "^2.0.0",
     "esvalid": "^1.1.0",
     "istanbul": "^0.3.5",
     "matcha": "^0.6.0",
-    "mocha": "^2.1.0",
-    "rimraf": "^2.2.8",
+    "mocha": "2.2.0",
+    "rimraf": "^2.3.2",
     "uglify-js": "^2.4.16"
   }
 }

packages/babel-cli/README.md

@@ -0,0 +1,5 @@
+# babel-cli
+
+Babel CLI
+
+For more information please look at [babel](https://github.com/babel/babel).

packages/babel-cli/bin/_babel-node

@@ -4,6 +4,7 @@ var pathIsAbsolute = require("path-is-absolute");
 var commander      = require("commander");
 var Module         = require("module");
 var babel          = require("babel-core");
+var inspect        = require("util").inspect;
 var path           = require("path");
 var repl           = require("repl");
 var util           = require("babel-core").util;
@@ -71,7 +72,10 @@ if (program.eval || program.print) {
   global.require = module.require.bind(module);
 
   var result = _eval(code, global.__filename);
-  if (program.print) console.log(result);
+  if (program.print) {
+    var output = _.isString(result) ? result : inspect(result);
+    process.stdout.write(output + "\n");
+  }
 } else {
   if (program.args.length) {
     // slice all arguments up to the first filename since they're babel args that we handle

packages/babel-cli/bin/babel/dir.js

@@ -28,6 +28,8 @@ module.exports = function (commander, filenames, opts) {
   };
 
   var handleFile = function (src, filename) {
+    if (util.shouldIgnore(src)) return;
+
     if (util.canCompile(filename)) {
       write(src, filename);
     } else if (commander.copyFiles) {

packages/babel-cli/bin/babel/file.js

@@ -107,6 +107,8 @@ module.exports = function (commander, filenames, opts) {
     });
 
     _.each(_filenames, function (filename) {
+      if (util.shouldIgnore(filename)) return;
+
       results.push(util.compile(filename));
     });
 

packages/babel-cli/bin/babel/index.js

@@ -102,12 +102,15 @@ if (errors.length) {
 
 //
 
-exports.opts = {};
+var opts = exports.opts = {};
 
 each(options, function (opt, key) {
-  exports.opts[key] = commander[key];
+  opts[key] = commander[key];
 });
 
+opts.ignore = util.arrayify(opts.ignore, util.regexify);
+opts.only   = util.arrayify(opts.only, util.regexify);
+
 var fn;
 
 if (commander.outDir) {

packages/babel-cli/bin/babel/util.js

@@ -16,6 +16,10 @@ exports.readdir = readdir;
 
 exports.canCompile = util.canCompile;
 
+exports.shouldIgnore = function (loc) {
+  return util.shouldIgnore(loc, index.opts.ignore, index.opts.only);
+};
+
 exports.addSourceMappingUrl = function (code, loc) {
   return code + "\n//# sourceMappingURL=" + path.basename(loc);
 };
@@ -23,6 +27,8 @@ exports.addSourceMappingUrl = function (code, loc) {
 exports.transform = function (filename, code, opts) {
   opts = _.defaults(opts || {}, index.opts);
   opts.filename = filename;
+  opts.ignore = null;
+  opts.only = null;
 
   var result = babel.transform(code, opts);
   result.filename = filename;

packages/babel-cli/package.json

@@ -1,14 +1,14 @@
 {
   "name": "babel",
   "description": "Turn ES6 code into readable vanilla ES5 with source maps",
-  "version": "5.0.2",
+  "version": "5.0.13",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
   "repository": "babel/babel",
   "preferGlobal": true,
   "dependencies": {
-    "chokidar": "^0.12.6",
-    "babel-core": "^5.0.2",
+    "babel-core": "^5.0.13",
+    "chokidar": "^1.0.0",
     "commander": "^2.6.0",
     "fs-readdir-recursive": "^0.1.0",
     "output-file-sync": "^1.1.0",

packages/babel-runtime/package.json

@@ -1,7 +1,7 @@
 {
   "name": "babel-runtime",
   "description": "babel selfContained runtime",
-  "version": "5.0.2",
+  "version": "5.0.13",
   "repository": "babel/babel",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "dependencies": {

packages/build-runtime.js

@@ -13,16 +13,20 @@ function relative(filename) {
   return __dirname + "/babel-runtime/" + filename;
 }
 
-function readFile(filename, defaultify) {
+function readFile(filename, shouldDefaultify) {
   var file = fs.readFileSync(require.resolve(filename), "utf8");
 
-  if (defaultify) {
-    file += '\nmodule.exports = { "default": module.exports, __esModule: true };\n';
+  if (shouldDefaultify) {
+    file += "\n" + defaultify("module.exports") + "\n";
   }
 
   return file;
 }
 
+function defaultify(name) {
+  return 'module.exports = { "default": ' + name + ', __esModule: true };';
+}
+
 function updatePackage() {
   var pkgLoc = relative("package.json");
   var pkg    = require(pkgLoc);
@@ -69,4 +73,26 @@ each(File.helpers, function (helperName) {
 writeFile("regenerator/index.js", readFile("regenerator-babel/runtime-module", true));
 writeFile("regenerator/runtime.js", selfContainify(readFile("regenerator-babel/runtime")));
 
+//
+
+var coreDefinitions = require("../lib/babel/transformation/transformers/other/runtime/definitions");
+
+var paths = [];
+
+each(coreDefinitions.builtins, function (path) {
+  paths.push(path);
+});
+
+each(coreDefinitions.methods, function (props) {
+  each(props, function (path) {
+    paths.push(path);
+  });
+});
+
+each(paths, function (path) {
+  writeFile("core-js/" + path + ".js", defaultify('require("core-js/library/fn/' + path + '")'));
+});
+
+//
+
 updatePackage();

src/acorn/src/expression.js

@@ -93,13 +93,15 @@ pp.parseMaybeAssign = function(noIn, refShorthandDefaultPos, afterLeftParse) {
     failOnShorthandAssign = false
   }
   let start = this.markPosition()
+  if (this.type == tt.parenL || this.type == tt.name)
+    this.potentialArrowAt = this.start
   let left = this.parseMaybeConditional(noIn, refShorthandDefaultPos)
   if (afterLeftParse) left = afterLeftParse.call(this, left, start)
   if (this.type.isAssign) {
     let node = this.startNodeAt(start)
     node.operator = this.value
     node.left = this.type === tt.eq ? this.toAssignable(left) : left
-    refShorthandDefaultPos.start = 0; // reset because shorthand default was used correctly
+    refShorthandDefaultPos.start = 0 // reset because shorthand default was used correctly
     this.checkLVal(left)
     if (left.parenthesizedExpression) {
       if (left.type === "ObjectPattern") {
@@ -224,7 +226,7 @@ pp.parseSubscripts = function(base, start, noCalls) {
   } else if (!noCalls && this.eat(tt.parenL)) {
     let node = this.startNodeAt(start)
     node.callee = base
-    node.arguments = this.parseExprList(tt.parenR, false)
+    node.arguments = this.parseExprList(tt.parenR, this.options.features["es7.trailingFunctionCommas"])
     return this.parseSubscripts(this.finishNode(node, "CallExpression"), start, noCalls)
   } else if (this.type === tt.backQuote) {
     let node = this.startNodeAt(start)
@@ -240,7 +242,7 @@ pp.parseSubscripts = function(base, start, noCalls) {
 // or `{}`.
 
 pp.parseExprAtom = function(refShorthandDefaultPos) {
-  let node
+  let node, canBeArrow = this.potentialArrowAt == this.start
   switch (this.type) {
   case tt._this:
   case tt._super:
@@ -250,7 +252,7 @@ pp.parseExprAtom = function(refShorthandDefaultPos) {
     return this.finishNode(node, type)
 
   case tt._yield:
-    if (this.inGenerator) unexpected()
+    if (this.inGenerator) this.unexpected()
 
   case tt._do:
     if (this.options.features["es7.doExpressions"]) {
@@ -271,7 +273,7 @@ pp.parseExprAtom = function(refShorthandDefaultPos) {
       if (id.name === "async") {
         // arrow functions
         if (this.type === tt.parenL) {
-          let expr = this.parseParenAndDistinguishExpression(start, true)
+          let expr = this.parseParenAndDistinguishExpression(start, true, true)
           if (expr && expr.type === "ArrowFunctionExpression") {
             return expr
           } else {
@@ -302,9 +304,8 @@ pp.parseExprAtom = function(refShorthandDefaultPos) {
     }
     //
 
-    if (!this.canInsertSemicolon() && this.eat(tt.arrow)) {
+    if (canBeArrow && !this.canInsertSemicolon() && this.eat(tt.arrow))
       return this.parseArrowExpression(this.startNodeAt(start), [id])
-    }
     return id
 
   case tt.regexp:
@@ -324,7 +325,7 @@ pp.parseExprAtom = function(refShorthandDefaultPos) {
     return this.finishNode(node, "Literal")
 
   case tt.parenL:
-    return this.parseParenAndDistinguishExpression()
+    return this.parseParenAndDistinguishExpression(null, null, canBeArrow)
 
   case tt.bracketL:
     node = this.startNode()
@@ -378,7 +379,7 @@ pp.parseParenExpression = function() {
   return val
 }
 
-pp.parseParenAndDistinguishExpression = function(start, isAsync) {
+pp.parseParenAndDistinguishExpression = function(start, isAsync, canBeArrow) {
   start = start || this.markPosition()
   let val
   if (this.options.ecmaVersion >= 6) {
@@ -407,7 +408,7 @@ pp.parseParenAndDistinguishExpression = function(start, isAsync) {
     let innerEnd = this.markPosition()
     this.expect(tt.parenR)
 
-    if (!this.canInsertSemicolon() && this.eat(tt.arrow)) {
+    if (canBeArrow && !this.canInsertSemicolon() && this.eat(tt.arrow)) {
       if (innerParenStart) this.unexpected(innerParenStart)
       return this.parseParenArrowList(start, exprList, isAsync)
     }
@@ -515,10 +516,15 @@ pp.parseObj = function(isPattern, refShorthandDefaultPos) {
       if (this.afterTrailingComma(tt.braceR)) break
     } else first = false
 
+    while (this.type === tt.at) {
+      this.decorators.push(this.parseDecorator())
+    }
+
     let prop = this.startNode(), isGenerator = false, isAsync = false, start
     if (this.options.features["es7.objectRestSpread"] && this.type === tt.ellipsis) {
       prop = this.parseSpread()
       prop.type = "SpreadProperty"
+      this.takeDecorators(prop)
       node.properties.push(prop)
       continue
     }
@@ -544,8 +550,12 @@ pp.parseObj = function(isPattern, refShorthandDefaultPos) {
     }
     this.parseObjPropValue(prop, start, isGenerator, isAsync, isPattern, refShorthandDefaultPos);
     this.checkPropClash(prop, propHash)
+    this.takeDecorators(prop)
     node.properties.push(this.finishNode(prop, "Property"))
   }
+  if (this.decorators.length) {
+    this.raise(this.start, "You have trailing decorators with no property");
+  }
   return this.finishNode(node, isPattern ? "ObjectPattern" : "ObjectExpression")
 }
 
@@ -726,7 +736,7 @@ pp.parseAwait = function (node) {
     this.unexpected()
   }
   node.all = this.eat(tt.star)
-  node.argument = this.parseMaybeAssign(true)
+  node.argument = this.parseMaybeUnary()
   return this.finishNode(node, "AwaitExpression")
 };
 

src/acorn/src/lookahead.js

@@ -18,17 +18,19 @@ var STATE_KEYS = [
 ];
 
 pp.getState = function () {
-  var state = {};
+  var state = {}
   for (var i = 0; i < STATE_KEYS.length; i++) {
-    var key = STATE_KEYS[i];
-    state[key] = this[key];
+    var key = STATE_KEYS[i]
+    state[key] = this[key]
   }
-  return state;
+  return state
 };
 
 pp.lookahead = function() {
   var old = this.getState();
-  this.next();
+  this.isLookahead = true
+  this.next()
+  this.isLookahead = false
   var curr = this.getState();
   for (var key in old) this[key] = old[key];
   return curr;

src/acorn/src/lval.js

@@ -125,7 +125,9 @@ pp.parseBindingList = function(close, allowEmpty, allowTrailingComma) {
       this.expect(close)
       break
     } else {
-      elts.push(this.parseAssignableListItemTypes(this.parseMaybeDefault()))
+      var left = this.parseMaybeDefault()
+      this.parseAssignableListItemTypes(left)
+      elts.push(this.parseMaybeDefault(null, left))
     }
   }
   return elts

src/acorn/src/state.js

@@ -46,6 +46,9 @@ export function Parser(options, input, startPos) {
   this.inModule = this.options.sourceType === "module"
   this.strict = this.options.strictMode === false ? false : this.inModule
 
+  // Used to signify the start of a potential arrow function
+  this.potentialArrowAt = -1
+
   // Flags to track whether we are in a function, a generator.
   this.inFunction = this.inGenerator = false
   // Labels in scope.

src/acorn/src/statement.js

@@ -458,7 +458,7 @@ pp.parseFunction = function(node, isStatement, allowExpressionBody, isAsync) {
 
 pp.parseFunctionParams = function(node) {
   this.expect(tt.parenL)
-  node.params = this.parseBindingList(tt.parenR, false, false)
+  node.params = this.parseBindingList(tt.parenR, false, this.options.features["es7.trailingFunctionCommas"])
 }
 
 // Parse a class declaration or literal (depending on the
@@ -475,7 +475,7 @@ pp.parseClass = function(node, isStatement) {
     if (this.eat(tt.semi)) continue
     if (this.type === tt.at) {
       this.decorators.push(this.parseDecorator())
-      continue;
+      continue
     }
     var method = this.startNode()
     this.takeDecorators(method)

src/acorn/src/tokenize.js

@@ -28,7 +28,7 @@ const pp = Parser.prototype
 // Move to the next token
 
 pp.next = function() {
-  if (this.options.onToken)
+  if (this.options.onToken && !this.isLookahead)
     this.options.onToken(new Token(this))
 
   this.lastTokEnd = this.end

src/babel/api/register/cache.js

@@ -1,12 +1,9 @@
 import path from "path";
 import os from "os";
 import fs from "fs";
+import userHome from "user-home";
 
-function getUserHome() {
-  return process.env.HOME || process.env.HOMEPATH || process.env.USERPROFILE;
-}
-
-const FILENAME = process.env.BABEL_CACHE_PATH || path.join(getUserHome() || os.tmpdir(), ".babel.json");
+const FILENAME = process.env.BABEL_CACHE_PATH || path.join(userHome || os.tmpdir(), ".babel.json");
 var data = {};
 
 export function save() {

src/babel/generation/generators/expressions.js

@@ -169,4 +169,8 @@ export function MemberExpression(node, print) {
   }
 }
 
-export { MemberExpression as MetaProperty };
+export function MetaProperty(node, print) {
+  print(node.meta);
+  this.push(".");
+  print(node.property);
+}

src/babel/generation/generators/methods.js

@@ -75,5 +75,16 @@ export function ArrowFunctionExpression(node, print) {
   }
 
   this.push(" => ");
+
+  const bodyNeedsParens = t.isObjectExpression(node.body);
+
+  if (bodyNeedsParens) {
+    this.push("(");
+  }
+
   print(node.body);
+
+  if (bodyNeedsParens) {
+    this.push(")");
+  }
 }

src/babel/patch.js

@@ -7,15 +7,15 @@ import * as t from "./types";
 
 extend(estraverse.VisitorKeys, t.VISITOR_KEYS);
 
-// regenerator-babel/ast-types
+// regenerator/ast-types
 
 var def = types.Type.def;
 var or  = types.Type.or;
 
-def("File")
-  .bases("Node")
-  .build("program")
-  .field("program", def("Program"));
+//def("File")
+//  .bases("Node")
+//  .build("program")
+//  .field("program", def("Program"));
 
 def("AssignmentPattern")
   .bases("Pattern")

src/babel/polyfill.js

@@ -4,4 +4,4 @@ if (global._babelPolyfill) {
 global._babelPolyfill = true;
 
 import "core-js/shim";
-import "regenerator-babel/runtime";
+import "regenerator/runtime";

src/babel/tools/resolve-rc.js

@@ -1,3 +1,4 @@
+import stripJsonComments from "strip-json-comments";
 import merge from "lodash/object/merge";
 import path from "path";
 import fs from "fs";
@@ -24,7 +25,7 @@ export default function (loc, opts = {}) {
       var json;
 
       try {
-        json = jsons[content] ||= JSON.parse(content);
+        json = jsons[content] ||= JSON.parse(stripJsonComments(content));
       } catch (err) {
         err.message = `${file}: ${err.message}`;
         throw err;
@@ -43,8 +44,11 @@ export default function (loc, opts = {}) {
       find(up, rel);
     }
   }
-
-  find(loc, rel);
+  
+  if (opts.breakConfig !== true) {
+    find(loc, rel);
+  }
+  
 
   return opts;
 };

src/babel/transformation/file/index.js

@@ -36,10 +36,9 @@ function checkNode(stack, node, scope) {
 
 export default class File {
   constructor(opts = {}) {
-    this.dynamicImportedNoDefault = [];
-    this.dynamicImportIds         = {};
-    this.dynamicImported          = [];
-    this.dynamicImports           = [];
+    this.dynamicImportAbsoluteDefaults = [];
+    this.dynamicImportIds              = {};
+    this.dynamicImports                = [];
 
     this.usedHelpers = {};
     this.dynamicData = {};
@@ -59,6 +58,7 @@ export default class File {
     "defaults",
     "create-class",
     "create-decorated-class",
+    "create-decorated-object",
     "tagged-template-literal",
     "tagged-template-literal-loose",
     "interop-require",
@@ -85,6 +85,8 @@ export default class File {
     "default-props"
   ];
 
+  static soloHelpers = [];
+
   static options = require("./options");
 
   normalizeOptions(opts: Object) {
@@ -267,7 +269,7 @@ export default class File {
 
     // validate Transformer instance
     if (!plugin.buildPass || plugin.constructor.name !== "Transformer") {
-      throw new TypeError(`Plugin ${JSON.stringify(name)} didn't export default a Transformer instance`);
+      throw new TypeError(`Plugin ${JSON.stringify(name)} didn't export a default Transformer instance`);
     }
 
     // build!
@@ -332,7 +334,7 @@ export default class File {
     return source;
   }
 
-  addImport(source: string, name?: string, noDefault?: boolean): Object {
+  addImport(source: string, name?: string, absoluteDefault?: boolean): Object {
     name ||= source;
     var id = this.dynamicImportIds[name];
 
@@ -343,9 +345,7 @@ export default class File {
       var specifiers = [t.importDefaultSpecifier(id)];
       var declar = t.importDeclaration(specifiers, t.literal(source));
       declar._blockHoist = 3;
-
-      this.dynamicImported.push(declar);
-      if (noDefault) this.dynamicImportedNoDefault.push(declar);
+      if (absoluteDefault) this.dynamicImportAbsoluteDefaults.push(declar);
 
       if (this.transformers["es6.modules"].canTransform()) {
         this.moduleFormatter.importSpecifier(specifiers[0], declar, this.dynamicImports);
@@ -375,7 +375,9 @@ export default class File {
   }
 
   addHelper(name: string): Object {
-    if (!includes(File.helpers, name)) {
+    var isSolo = includes(File.soloHelpers, name);
+
+    if (!isSolo && !includes(File.helpers, name)) {
       throw new ReferenceError(`Unknown helper ${name}`);
     }
 
@@ -386,24 +388,26 @@ export default class File {
 
     this.usedHelpers[name] = true;
 
-    var generator = this.get("helperGenerator");
-    var runtime   = this.get("helpersNamespace");
-    if (generator) {
-      return generator(name);
-    } else if (runtime) {
-      var id = t.identifier(t.toIdentifier(name));
-      return t.memberExpression(runtime, id);
-    } else {
-      var ref = util.template("helper-" + name);
-      ref._compact = true;
-      var uid = this.scope.generateUidIdentifier(name);
-      this.scope.push({
-        key: name,
-        id: uid,
-        init: ref
-      });
-      return uid;
+    if (!isSolo) {
+      var generator = this.get("helperGenerator");
+      var runtime   = this.get("helpersNamespace");
+      if (generator) {
+        return generator(name);
+      } else if (runtime) {
+        var id = t.identifier(t.toIdentifier(name));
+        return t.memberExpression(runtime, id);
+      }
     }
+
+    var ref = util.template("helper-" + name);
+    ref._compact = true;
+    var uid = this.scope.generateUidIdentifier(name);
+    this.scope.push({
+      key: name,
+      id: uid,
+      init: ref
+    });
+    return uid;
   }
 
   errorWithNode(node, msg, Error = SyntaxError) {
@@ -422,23 +426,7 @@ export default class File {
 
   shouldIgnore() {
     var opts = this.opts;
-
-    var filename = opts.filename;
-    var ignore   = opts.ignore;
-    var only     = opts.only;
-
-    if (only.length) {
-      for (var i = 0; i < only.length; i++) {
-        if (only[i].test(filename)) return false;
-      }
-      return true;
-    } else if (ignore.length) {
-      for (var i = 0; i < ignore.length; i++) {
-        if (ignore[i].test(filename)) return true;
-      }
-    }
-
-    return false;
+    return util.shouldIgnore(opts.filename, opts.ignore, opts.only);
   }
 
   parse(code: string) {

src/babel/transformation/helpers/build-react-transformer.js

@@ -19,7 +19,7 @@ export default function (exports, opts) {
   exports.JSXIdentifier = function (node, parent) {
     if (node.name === "this" && t.isReferenced(node, parent)) {
       return t.thisExpression();
-    } else if (esutils.keyword.isIdentifierName(node.name)) {
+    } else if (esutils.keyword.isIdentifierNameES6(node.name)) {
       node.type = "Identifier";
     } else {
       return t.literal(node.name);

src/babel/transformation/helpers/call-delegate.js

@@ -1,10 +1,33 @@
+import traverse from "../../traversal";
 import * as t from "../../types";
 
-export default function (node) {
-  var container = t.functionExpression(null, [], node.body, node.generator, node.async);
-  container.shadow = true;
+var visitor = {
+  enter(node, parent, scope, state) {
+    if (this.isThisExpression() || this.isReferencedIdentifier({ name: "arguments" })) {
+      state.found = true;
+      this.stop();
+    }
 
-  var call = t.callExpression(container, []);
+    if (this.isFunction()) {
+      this.skip();
+    }
+  }
+};
+
+export default function (node, scope) {
+  var container = t.functionExpression(null, [], node.body, node.generator, node.async);
+
+  var callee = container;
+  var args   = [];
+
+  var state = { found: false };
+  scope.traverse(node, visitor, state);
+  if (state.found) {
+    callee = t.memberExpression(container, t.identifier("apply"));
+    args = [t.thisExpression(), t.identifier("arguments")];
+  }
+
+  var call = t.callExpression(callee, args);
   if (node.generator) call = t.yieldExpression(call, true);
 
   return t.returnStatement(call);

src/babel/transformation/helpers/define-map.js

@@ -4,17 +4,45 @@ import each from "lodash/collection/each";
 import has from "lodash/object/has";
 import * as t from "../../types";
 
-export function push(mutatorMap, key, kind, computed, value) {
-  var alias = t.toKeyAlias({ computed }, key);
+export function push(mutatorMap, node, kind, file) {
+  var alias = t.toKeyAlias(node);
+
+  //
 
   var map = {};
   if (has(mutatorMap, alias)) map = mutatorMap[alias];
   mutatorMap[alias] = map;
 
-  map._key = key;
-  if (computed) map._computed = true;
+  //
 
-  map[kind] = value;
+  map._inherits ||= [];
+  map._inherits.push(node);
+
+  map._key = node.key;
+
+  if (node.computed) {
+    map._computed = true;
+  }
+
+  if (node.decorators) {
+    var decorators = map.decorators ||= t.arrayExpression([]);
+    decorators.elements = decorators.elements.concat(node.decorators.map(dec => dec.expression));
+  }
+
+  if (map.value || map.initializer) {
+    throw file.errorWithNode(node, "Key conflict with sibling node");
+  }
+
+  if (node.value) {
+    if (node.kind === "init") kind = "value";
+    if (node.kind === "get") kind = "get";
+    if (node.kind === "set") kind = "set";
+
+    t.inheritsComments(node.value, node);
+    map[kind] = node.value;
+  }
+
+  return map;
 }
 
 export function hasComputed(mutatorMap) {

src/babel/transformation/helpers/name-method.js

@@ -27,6 +27,7 @@ var wrap = function (state, method, id, scope) {
       FUNCTION_ID: id,
       FUNCTION_KEY: scope.generateUidIdentifier(id.name)
     });
+    template.callee._skipModulesRemap = true;
 
     // shim in dummy params to retain function arity, if you try to read the
     // source then you'll get the original since it's proxied so it's all good
@@ -98,6 +99,7 @@ export function property(node, file, scope) {
   if (!t.isLiteral(key)) return node; // we can't set a function id with this
 
   var name = t.toIdentifier(key.value);
+  if (name === "eval" || name === "arguments") name = "_" + name;
   var id = t.identifier(name);
 
   var method = node.value;

src/babel/transformation/modules/_default.js

@@ -46,7 +46,11 @@ var remapVisitor = {
       }
     }
 
-    if (t.isAssignmentExpression(node)) {
+    if (node._skipModulesRemap) {
+      return this.skip();
+    }
+
+    if (t.isAssignmentExpression(node) && !node._ignoreModulesRemap) {
       var exported = formatter.getExport(node.left, scope);
       if (exported) {
         this.skip();
@@ -61,7 +65,6 @@ var importsVisitor = {
     enter(node, parent, scope, formatter) {
       formatter.hasLocalImports = true;
       extend(formatter.localImports, this.getBindingIdentifiers());
-      formatter.bumpImportOccurences(node);
     }
   }
 };
@@ -69,7 +72,7 @@ var importsVisitor = {
 var exportsVisitor = traverse.explode({
   ExportDeclaration: {
     enter(node, parent, scope, formatter) {
-      formatter.hasLocalImports = true;
+      formatter.hasLocalExports = true;
 
       var declar = this.get("declaration");
       if (declar.isStatement()) {
@@ -96,29 +99,23 @@ var exportsVisitor = traverse.explode({
           formatter.hasNonDefaultExports = true;
         }
       }
-
-      if (node.source) {
-        formatter.bumpImportOccurences(node);
-      }
     }
   }
 });
 
 export default class DefaultFormatter {
   constructor(file) {
-    this.internalRemap = {};
-
-    this.defaultIds = object();
-    this.scope      = file.scope;
-    this.file       = file;
-    this.ids        = object();
+    this.internalRemap = object();
+    this.defaultIds    = object();
+    this.scope         = file.scope;
+    this.file          = file;
+    this.ids           = object();
 
     this.hasNonDefaultExports = false;
 
     this.hasLocalExports = false;
     this.hasLocalImports = false;
 
-    this.localImportOccurences = object();
     this.localExports = object();
     this.localImports = object();
 
@@ -134,15 +131,6 @@ export default class DefaultFormatter {
     return (t.isExportDefaultDeclaration(node) || t.isSpecifierDefault(node)) && !this.noInteropRequireExport && !this.hasNonDefaultExports;
   }
 
-  bumpImportOccurences(node) {
-    var source = node.source.value;
-    var occurs = this.localImportOccurences;
-    occurs[source] ||= 0;
-    if (node.specifiers) {
-      occurs[source] += node.specifiers.length;
-    }
-  }
-
   getLocalExports() {
     this.file.path.traverse(exportsVisitor, this);
   }
@@ -152,7 +140,7 @@ export default class DefaultFormatter {
   }
 
   remapAssignments() {
-    if (this.hasLocalImports) {
+    if (this.hasLocalExports || this.hasLocalImports) {
       this.file.path.traverse(remapVisitor, this);
     }
   }

src/babel/transformation/modules/amd.js

@@ -6,7 +6,9 @@ import * as util from  "../../util";
 import * as t from "../../types";
 
 export default class AMDFormatter extends DefaultFormatter {
-  init = CommonFormatter.prototype.init;
+  init() {
+    CommonFormatter.prototype._init.call(this, this.hasNonDefaultExports);
+  }
 
   buildDependencyLiterals() {
     var names = [];
@@ -78,9 +80,10 @@ export default class AMDFormatter extends DefaultFormatter {
       this.defaultIds[key] = specifier.local;
     }
 
-    if (includes(this.file.dynamicImportedNoDefault, node)) {
-      // Prevent unnecessary renaming of dynamic imports.
+    if (includes(this.file.dynamicImportAbsoluteDefaults, node)) {
+      // prevent unnecessary renaming of dynamic imports
       this.ids[node.source.value] = ref;
+      ref = t.memberExpression(ref, t.identifier("default"));
     } else if (t.isImportNamespaceSpecifier(specifier)) {
       // import * as bar from "foo";
     } else if (!includes(this.file.dynamicImported, node) && t.isSpecifierDefault(specifier) && !this.noInteropRequireImport) {
@@ -100,15 +103,34 @@ export default class AMDFormatter extends DefaultFormatter {
     this.internalRemap[specifier.local.name] = ref;
   }
 
-  exportSpecifier() {
-    CommonFormatter.prototype.exportSpecifier.apply(this, arguments);
+  exportSpecifier(specifier, node, nodes) {
+    if (this.doDefaultExportInterop(specifier)) {
+      nodes.push(util.template("exports-default-assign", {
+        VALUE: specifier.local
+      }, true));
+    } else {
+      CommonFormatter.prototype.exportSpecifier.apply(this, arguments);
+    }
   }
 
-  exportDeclaration(node) {
+  exportDeclaration(node, nodes) {
     if (this.doDefaultExportInterop(node)) {
       this.passModuleArg = true;
+
+      var declar = node.declaration;
+      var assign = util.template("exports-default-assign", {
+        VALUE: this._pushStatement(declar, nodes)
+      }, true);
+
+      if (t.isFunctionDeclaration(declar)) {
+        // we can hoist this assignment to the top of the file
+        assign._blockHoist = 3;
+      }
+
+      nodes.push(assign);
+      return;
     }
 
-    CommonFormatter.prototype.exportDeclaration.apply(this, arguments);
+    DefaultFormatter.prototype.exportDeclaration.apply(this, arguments);
   }
 }

src/babel/transformation/modules/common.js

@@ -5,13 +5,17 @@ import * as t from "../../types";
 
 export default class CommonJSFormatter extends DefaultFormatter {
   init() {
+    this._init(this.hasLocalExports);
+  }
+
+  _init(conditional) {
     var file  = this.file;
     var scope = file.scope;
 
     scope.rename("module");
     scope.rename("exports");
 
-    if (!this.noInteropRequireImport && this.hasNonDefaultExports) {
+    if (!this.noInteropRequireImport && conditional) {
       var templateName = "exports-module-declaration";
       if (this.file.isLoose("es6.modules")) templateName += "-loose";
       var declar = util.template(templateName, true);
@@ -20,6 +24,20 @@ export default class CommonJSFormatter extends DefaultFormatter {
     }
   }
 
+  transform(program) {
+    DefaultFormatter.prototype.transform.apply(this, arguments);
+
+    if (this.hasDefaultOnlyExport) {
+      program.body.push(
+        t.expressionStatement(t.assignmentExpression(
+          "=",
+          t.memberExpression(t.identifier("module"), t.identifier("exports")),
+          t.memberExpression(t.identifier("exports"), t.identifier("default"))
+        ))
+      );
+    }
+  }
+
   importSpecifier(specifier, node, nodes) {
     var variableName = specifier.local;
 
@@ -27,16 +45,18 @@ export default class CommonJSFormatter extends DefaultFormatter {
 
     // import foo from "foo";
     if (t.isSpecifierDefault(specifier)) {
-      if (includes(this.file.dynamicImportedNoDefault, node)) {
+      if (includes(this.file.dynamicImportAbsoluteDefaults, node)) {
         this.internalRemap[variableName.name] = ref;
+      } else if (this.noInteropRequireImport) {
+        this.internalRemap[variableName.name] = t.memberExpression(ref, t.identifier("default"));
       } else {
-        if (this.noInteropRequireImport) {
-          this.internalRemap[variableName.name] = t.memberExpression(ref, t.identifier("default"))
-        } else if (!includes(this.file.dynamicImported, node)) {
-          nodes.push(t.variableDeclaration("var", [
-            t.variableDeclarator(variableName, t.callExpression(this.file.addHelper("interop-require"), [ref]))
-          ]));
-        }
+        var uid = this.scope.generateUidBasedOnNode(node, "import");
+
+        nodes.push(t.variableDeclaration("var", [
+          t.variableDeclarator(uid, t.callExpression(this.file.addHelper("interop-require-wildcard"), [ref]))
+        ]));
+
+        this.internalRemap[variableName.name] = t.memberExpression(uid, t.identifier("default"));
       }
     } else {
       if (t.isImportNamespaceSpecifier(specifier)) {
@@ -64,29 +84,15 @@ export default class CommonJSFormatter extends DefaultFormatter {
 
   exportSpecifier(specifier, node, nodes) {
     if (this.doDefaultExportInterop(specifier)) {
-      nodes.push(util.template("exports-default-assign", {
-        VALUE: specifier.local
-      }, true));
-      return;
-    } else {
-      DefaultFormatter.prototype.exportSpecifier.apply(this, arguments);
+      this.hasDefaultOnlyExport = true;
     }
+
+    DefaultFormatter.prototype.exportSpecifier.apply(this, arguments);
   }
 
   exportDeclaration(node, nodes) {
     if (this.doDefaultExportInterop(node)) {
-      var declar = node.declaration;
-      var assign = util.template("exports-default-assign", {
-        VALUE: this._pushStatement(declar, nodes)
-      }, true);
-
-      if (t.isFunctionDeclaration(declar)) {
-        // we can hoist this assignment to the top of the file
-        assign._blockHoist = 3;
-      }
-
-      nodes.push(assign);
-      return;
+      this.hasDefaultOnlyExport = true;
     }
 
     DefaultFormatter.prototype.exportDeclaration.apply(this, arguments);
@@ -98,7 +104,7 @@ export default class CommonJSFormatter extends DefaultFormatter {
     var call = t.callExpression(t.identifier("require"), [node.source]);
     var uid;
 
-    if (includes(this.file.dynamicImported, node) && !includes(this.file.dynamicImportedNoDefault, node)) {
+    if (includes(this.file.dynamicImportAbsoluteDefaults, node)) {
       call = t.memberExpression(call, t.identifier("default"));
       uid = node.specifiers[0].local;
     } else {

src/babel/transformation/modules/system.js

@@ -6,12 +6,8 @@ import each from "lodash/collection/each";
 import map from "lodash/collection/map";
 import * as t from "../../types";
 
-var canHoist = function (node, file) {
-  return node._blockHoist && !file.transformers.runtime.canTransform();
-}
-
 var hoistVariablesVisitor = {
-  enter(node, parent, scope, hoistDeclarators) {
+  enter(node, parent, scope, state) {
     if (t.isFunction(node)) {
       // nothing inside is accessible
       return this.skip();
@@ -24,13 +20,13 @@ var hoistVariablesVisitor = {
       }
 
       // ignore block hoisted nodes as these can be left in
-      if (canHoist(node, scope.file)) return;
+      if (state.formatter.canHoist(node)) return;
 
       var nodes = [];
 
       for (var i = 0; i < node.declarations.length; i++) {
         var declar = node.declarations[i];
-        hoistDeclarators.push(t.variableDeclarator(declar.id));
+        state.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));
@@ -40,14 +36,8 @@ var hoistVariablesVisitor = {
 
       // 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 nodes;
-        }
+      if (t.isFor(parent) && parent.left === node) {
+        return node.declarations[0].id;
       }
 
       return nodes;
@@ -56,11 +46,11 @@ var hoistVariablesVisitor = {
 };
 
 var hoistFunctionsVisitor = {
-  enter(node, parent, scope, handlerBody) {
+  enter(node, parent, scope, state) {
     if (t.isFunction(node)) this.skip();
 
-    if (t.isFunctionDeclaration(node) || canHoist(node, scope.file)) {
-      handlerBody.push(node);
+    if (t.isFunctionDeclaration(node) || state.formatter.canHoist(node)) {
+      state.handlerBody.push(node);
       this.remove();
     }
   }
@@ -174,6 +164,10 @@ export default class SystemFormatter extends AMDFormatter {
     }));
   }
 
+  canHoist(node) {
+    return node._blockHoist && !this.file.dynamicImports.length;
+  }
+
   transform(program) {
     DefaultFormatter.prototype.transform.apply(this, arguments);
 
@@ -197,7 +191,10 @@ export default class SystemFormatter extends AMDFormatter {
     var returnStatement = handlerBody.pop();
 
     // hoist up all variable declarations
-    this.file.scope.traverse(block, hoistVariablesVisitor, hoistDeclarators);
+    this.file.scope.traverse(block, hoistVariablesVisitor, {
+      formatter: this,
+      hoistDeclarators: hoistDeclarators
+    });
 
     if (hoistDeclarators.length) {
       var hoistDeclar = t.variableDeclaration("var", hoistDeclarators);
@@ -206,7 +203,10 @@ export default class SystemFormatter extends AMDFormatter {
     }
 
     // hoist up function declarations for circular references
-    this.file.scope.traverse(block, hoistFunctionsVisitor, handlerBody);
+    this.file.scope.traverse(block, hoistFunctionsVisitor, {
+      formatter: this,
+      handlerBody: handlerBody
+    });
 
     handlerBody.push(returnStatement);
 

src/babel/transformation/modules/umd.js

@@ -1,6 +1,7 @@
 import DefaultFormatter from "./_default";
 import AMDFormatter from "./amd";
 import values from "lodash/object/values";
+import path from "path";
 import * as util from  "../../util";
 import * as t from "../../types";
 
@@ -47,11 +48,11 @@ export default class UMDFormatter extends AMDFormatter {
 
     // globals
 
-    var browserArgs = [t.memberExpression(t.identifier("module"), t.identifier("exports"))];
-    if (this.passModuleArg) browserArgs.push(t.identifier("module"));
+    var browserArgs = [];
+    if (this.passModuleArg) browserArgs.push(t.identifier("mod"));
 
     for (let name in this.ids) {
-      var id = this.defaultIds[name] || t.identifier(t.toIdentifier(name));
+      var id = this.defaultIds[name] || t.identifier(t.toIdentifier(path.basename(name, path.extname(name))));
       browserArgs.push(t.memberExpression(t.identifier("global"), id));
     }
 
@@ -60,12 +61,17 @@ export default class UMDFormatter extends AMDFormatter {
     var moduleName = this.getModuleName();
     if (moduleName) defineArgs.unshift(t.literal(moduleName));
 
+    //
+    var globalArg = this.file.opts.basename;
+    if (moduleName) globalArg = moduleName;
+    globalArg = t.identifier(t.toIdentifier(globalArg));
+
     var runner = util.template("umd-runner-body", {
       AMD_ARGUMENTS: defineArgs,
       COMMON_TEST: commonTests,
       COMMON_ARGUMENTS: commonArgs,
       BROWSER_ARGUMENTS: browserArgs,
-      GLOBAL_ARG: t.identifier(t.toIdentifier(this.file.opts.basename))
+      GLOBAL_ARG: globalArg
     });
 
     //

src/babel/transformation/templates/.babelrc

@@ -1,4 +1,4 @@
 {
-  "blacklist": ["useStrict", "es6.blockScoping", "regenerator"],
+  "blacklist": ["useStrict", "es6.blockScoping", "regenerator", "es6.spread"],
   "loose": ["es6.modules"]
 }

src/babel/transformation/templates/class-super-native-constructor-call.js

@@ -0,0 +1,5 @@
+if (SUPER_NAME != null) {
+  var NATIVE_REF = new SUPER_NAME(...arguments);
+  NATIVE_REF.__proto__ = CLASS_NAME.prototype;
+  return NATIVE_REF;
+}

src/babel/transformation/templates/corejs-is-iterator.js

@@ -1 +0,0 @@
-CORE_ID.isIterable(VALUE);

src/babel/transformation/templates/corejs-iterator.js

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

src/babel/transformation/templates/helper-create-class.js

@@ -4,7 +4,7 @@
       var descriptor = props[i];
       descriptor.enumerable = descriptor.enumerable || false;
       descriptor.configurable = true;
-      if (descriptor.value) descriptor.writable = true;
+      if ("value" in descriptor) descriptor.writable = true;
       Object.defineProperty(target, descriptor.key, descriptor);
     }
   }

src/babel/transformation/templates/helper-create-decorated-object.js

@@ -0,0 +1,33 @@
+(function (descriptors) {
+  var target = {};
+
+  for (var i = 0; i < descriptors.length; i ++) {
+    var descriptor = descriptors[i];
+    var decorators = descriptor.decorators;
+    var key        = descriptor.key;
+
+    // don't want to expose these to userland since i know people will rely on them
+    // and think it's spec behaviour
+    delete descriptor.key;
+    delete descriptor.decorators;
+
+    descriptor.enumerable = true;
+    descriptor.configurable = true;
+    if ("value" in descriptor) descriptor.writable = true;
+
+    if (decorators) {
+      for (var f = 0; f < decorators.length; f++) {
+        var decorator = decorators[f];
+        if (typeof decorator === "function") {
+          descriptor = decorator(target, key, descriptor) || descriptor;
+        } else {
+          throw new TypeError("The decorator for method " + descriptor.key + " is of the invalid type " + typeof decorator);
+        }
+      }
+    }
+
+    Object.defineProperty(target, key, descriptor);
+  }
+
+  return target;
+})

src/babel/transformation/templates/property-method-assignment-wrapper-generator.js

@@ -4,7 +4,7 @@
   }
 
   FUNCTION_ID.toString = function () {
-    return FUNCTION_ID.toString();
+    return FUNCTION_KEY.toString();
   };
 
   return FUNCTION_ID;

src/babel/transformation/templates/property-method-assignment-wrapper.js

@@ -4,7 +4,7 @@
   }
 
   FUNCTION_ID.toString = function () {
-    return FUNCTION_ID.toString();
+    return FUNCTION_KEY.toString();
   }
 
   return FUNCTION_ID;

src/babel/transformation/templates/umd-runner-body.js

@@ -4,8 +4,8 @@
   } else if (COMMON_TEST) {
     factory(COMMON_ARGUMENTS);
   } else {
-    var module = { exports: {} };
-    factory(BROWSER_ARGUMENTS);
-    global.GLOBAL_ARG = module.exports;
+    var mod = { exports: {} };
+    factory(mod.exports, BROWSER_ARGUMENTS);
+    global.GLOBAL_ARG = mod.exports;
   }
 });

src/babel/transformation/transformers/es5/properties.mutators.js

@@ -5,14 +5,14 @@ export function check(node) {
   return t.isProperty(node) && (node.kind === "get" || node.kind === "set");
 }
 
-export function ObjectExpression(node) {
+export function ObjectExpression(node, parent, scope, file) {
   var mutatorMap = {};
   var hasAny = false;
 
   node.properties = node.properties.filter(function (prop) {
     if (prop.kind === "get" || prop.kind === "set") {
       hasAny = true;
-      defineMap.push(mutatorMap, prop.key, prop.kind, prop.computed, prop.value);
+      defineMap.push(mutatorMap, prop, prop.kind, file);
       return false;
     } else {
       return true;

src/babel/transformation/transformers/es6/classes.js

@@ -30,7 +30,7 @@ var collectPropertyReferencesVisitor = {
       }
 
       if (this.isReferenced() && scope.getBinding(node.name) === state.scope.getBinding(node.name)) {
-        state.references[node.name] = true;;
+        state.references[node.name] = true;
       }
     }
   }
@@ -62,11 +62,27 @@ var verifyConstructorVisitor = traverse.explode({
     }
   },
 
+  FunctionDeclaration: {
+    enter() {
+      this.skip();
+    }
+  },
+
+  FunctionExpression: {
+    enter() {
+      this.skip();
+    }
+  },
+
   ThisExpression: {
     enter(node, parent, scope, state) {
       if (state.hasSuper && !state.hasBareSuper) {
         throw this.errorWithNode("'this' is not allowed before super()");
       }
+
+      if (state.isNativeSuper) {
+        return state.nativeSuperRef;
+      }
     }
   }
 });
@@ -121,6 +137,15 @@ class ClassTransformer {
 
     //
 
+    var superClass = this.node.superClass;
+    this.isNativeSuper = superClass && t.isIdentifier(superClass) && t.NATIVE_TYPE_NAMES.indexOf(superClass.name) >= 0;
+
+    if (this.isNativeSuper) {
+      this.nativeSuperRef = this.scope.generateUidIdentifier("this");
+    }
+
+    //
+
     var body = this.body;
 
     //
@@ -143,7 +168,6 @@ class ClassTransformer {
     var closureArgs = [];
 
     //
-
     if (this.hasSuper) {
       closureArgs.push(superName);
 
@@ -155,27 +179,50 @@ class ClassTransformer {
     }
 
     //
+    var decorators = this.node.decorators;
+    if (decorators) {
+      // create a class reference to use later on
+      this.classRef = this.scope.generateUidIdentifier(classRef);
 
+      // this is so super calls and the decorators have access to the raw function
+      body.push(t.variableDeclaration("var", [
+        t.variableDeclarator(this.classRef, classRef)
+      ]));
+    }
+
+    //
     this.buildBody();
 
+    // make sure this class isn't directly called
     constructorBody.body.unshift(t.expressionStatement(t.callExpression(file.addHelper("class-call-check"), [
       t.thisExpression(),
-      classRef
+      this.classRef
     ])));
 
     //
 
-    var decorators = this.node.decorators;
     if (decorators) {
+      // reverse the decorators so we execute them in the right order
+      decorators = decorators.reverse();
+
       for (var i = 0; i < decorators.length; i++) {
         var decorator = decorators[i];
-        body.push(util.template("class-decorator", {
+
+        var decoratorNode = util.template("class-decorator", {
           DECORATOR: decorator.expression,
           CLASS_REF: classRef
-        }, true));
+        }, true);
+        decoratorNode.expression._ignoreModulesRemap = true;
+        body.push(decoratorNode);
       }
     }
 
+    if (this.isNativeSuper) {
+      // we've determined this is inheriting from a native class so return the constructed
+      // instance
+      constructorBody.body.push(t.returnStatement(this.nativeSuperRef));
+    }
+
     if (this.className) {
       // named class with only a constructor
       if (body.length === 1) return t.toExpression(body[0]);
@@ -216,44 +263,15 @@ class ClassTransformer {
       mutatorMap = this.instanceMutatorMap;
     }
 
-    var alias = t.toKeyAlias(node);
-
-    //
-
-    var map = {};
-    if (has(mutatorMap, alias)) map = mutatorMap[alias];
-    mutatorMap[alias] = map;
-
-    //
-
-    map._inherits ||= [];
-    map._inherits.push(node);
-
-    map._key = node.key;
+    var map = defineMap.push(mutatorMap, node, kind, this.file);
 
     if (enumerable) {
       map.enumerable = t.literal(true)
     }
 
-    if (node.computed) {
-      map._computed = true;
-    }
-
-    if (node.decorators) {
+    if (map.decorators) {
       this.hasDecorators = true;
-      var decorators = map.decorators ||= t.arrayExpression([]);
-      decorators.elements = decorators.elements.concat(node.decorators.map(dec => dec.expression));
     }
-
-    if (map.value || map.initializer) {
-      throw this.file.errorWithNode(node, "Key conflict with sibling node");
-    }
-
-    if (node.kind === "get") kind = "get";
-    if (node.kind === "set") kind = "set";
-
-    t.inheritsComments(node.value, node);
-    map[kind] = node.value;
   }
 
   /**
@@ -305,7 +323,9 @@ class ClassTransformer {
     if (!this.hasConstructor && this.hasSuper) {
       var helperName = "class-super-constructor-call";
       if (this.isLoose) helperName += "-loose";
+      if (this.isNativeSuper) helperName = "class-super-native-constructor-call";
       constructorBody.body.push(util.template(helperName, {
+        NATIVE_REF: this.nativeSuperRef,
         CLASS_NAME: className,
         SUPER_NAME: this.superName
       }, true));
@@ -434,19 +454,36 @@ class ClassTransformer {
 
    verifyConstructor(path: TraversalPath) {
     var state = {
-      hasBareSuper: false,
-      bareSuper:    null,
-      hasSuper:     this.hasSuper,
-      file:         this.file
+      nativeSuperRef: this.nativeSuperRef,
+      isNativeSuper:  this.isNativeSuper,
+      hasBareSuper:   false,
+      bareSuper:      null,
+      hasSuper:       this.hasSuper,
+      file:           this.file
     };
 
-    path.traverse(verifyConstructorVisitor, state);
+    path.get("value").traverse(verifyConstructorVisitor, state);
 
     this.bareSuper = state.bareSuper;
 
     if (!state.hasBareSuper && this.hasSuper) {
       throw path.errorWithNode("Derived constructor must call super()");
     }
+
+    if (this.isNativeSuper && this.bareSuper) {
+      this.bareSuper.replaceWithMultiple([
+        t.variableDeclaration("var", [
+          t.variableDeclarator(this.nativeSuperRef, t.newExpression(this.superName, this.bareSuper.node.arguments))
+        ]),
+
+        t.expressionStatement(t.assignmentExpression(
+          "=",
+          t.memberExpression(this.nativeSuperRef, t.identifier("__proto__")),
+          t.memberExpression(this.classRef, t.identifier("prototype"))
+        )),
+        t.expressionStatement(this.nativeSuperRef)
+      ]);
+    }
    }
 
   /**
@@ -483,8 +520,6 @@ class ClassTransformer {
    */
 
   pushProperty(node: { type: "ClassProperty" }) {
-    if (!node.value && !node.decorators) return;
-
     var key;
 
     this.scope.traverse(node, collectPropertyReferencesVisitor, {
@@ -511,16 +546,17 @@ class ClassTransformer {
         }, true));
       }
     } else {
-      if (node.static) {
-        // can just be added to the static map
-        this.pushToMap(node, true);
-      } else {
+      if (!node.static && node.value) {
         // add this to the instancePropBody which will be added after the super call in a derived constructor
         // or at the start of a constructor for a non-derived constructor
         this.instancePropBody.push(t.expressionStatement(
           t.assignmentExpression("=", t.memberExpression(t.thisExpression(), node.key), node.value)
         ));
+        node.value = t.identifier("undefined");
       }
+
+      // can just be added to the static map
+      this.pushToMap(node, true);
     }
   }
 

src/babel/transformation/transformers/es6/destructuring.js

@@ -126,10 +126,11 @@ export function AssignmentExpression(node, parent, scope, file) {
   if (!t.isPattern(node.left)) return;
 
   var ref = scope.generateUidIdentifier("temp");
-  scope.push({ id: ref });
 
   var nodes = [];
-  nodes.push(t.expressionStatement(t.assignmentExpression("=", ref, node.right)));
+  nodes.push(t.variableDeclaration("var", [
+    t.variableDeclarator(ref, node.right)
+  ]));
 
   var destructuring = new DestructuringTransformer({
     operator: node.operator,
@@ -137,6 +138,11 @@ export function AssignmentExpression(node, parent, scope, file) {
     scope: scope,
     nodes: nodes
   });
+
+  if (t.isArrayExpression(node.right)) {
+    destructuring.arrays[ref.name] = true;
+  }
+
   destructuring.init(node.left, ref);
 
   nodes.push(t.expressionStatement(ref));
@@ -332,7 +338,7 @@ class DestructuringTransformer {
       if (t.isSpreadProperty(prop)) continue;
 
       var key = prop.key;
-      if (t.isIdentifier(key)) key = t.literal(prop.key.name);
+      if (t.isIdentifier(key) && !prop.computed) key = t.literal(prop.key.name);
       keys.push(key);
     }
 
@@ -397,9 +403,14 @@ class DestructuringTransformer {
     if (pattern.elements.length > arr.elements.length) return;
     if (pattern.elements.length < arr.elements.length && !hasRest(pattern)) return false;
 
-    // deopt on holes
     for (var i = 0; i < pattern.elements.length; i++) {
-      if (!pattern.elements[i]) return false;
+      var elem = pattern.elements[i];
+
+      // deopt on holes
+      if (!elem) return false;
+
+      // deopt on member expressions
+      if (t.isMemberExpression(elem)) return false;
     }
 
     // deopt on reference to left side identifiers

src/babel/transformation/transformers/es6/for-of.js

@@ -17,9 +17,6 @@ export function ForOfStatement(node, parent, scope, file) {
   var loop   = build.loop;
   var block  = loop.body;
 
-  // inherit comments from the original loop
-  t.inheritsComments(loop, node);
-
   // ensure that it's a block so we can take all its statements
   t.ensureBlock(node);
 
@@ -32,6 +29,7 @@ export function ForOfStatement(node, parent, scope, file) {
   block.body = block.body.concat(node.body.body);
 
   t.inherits(loop, node);
+  t.inherits(loop.body, node.body);
 
   if (build.replaceParent) {
     this.parentPath.replaceWithMultiple(build.node);

src/babel/transformation/transformers/es6/parameters.default.js

@@ -92,7 +92,7 @@ exports.Function = function (node, parent, scope, file) {
   node.params = node.params.slice(0, lastNonDefaultParam);
 
   if (state.iife) {
-    body.push(callDelegate(node));
+    body.push(callDelegate(node, scope));
     node.body = t.blockStatement(body);
   } else {
     node.body.body = body.concat(node.body.body);

src/babel/transformation/transformers/es6/tail-call.js

@@ -179,7 +179,7 @@ class TailCallTransformer {
     if (this.vars.length > 0) {
       var declarations = flatten(map(this.vars, function (decl) {
         return decl.declarations;
-      }, this));
+      }));
       var assignment = reduceRight(declarations, function (expr, decl) {
         return t.assignmentExpression("=", decl.id, expr);
       }, t.identifier("undefined"));

src/babel/transformation/transformers/es7/decorators.js

@@ -1,4 +1,33 @@
+import * as defineMap from "../../helpers/define-map";
+import * as t from "../../../types";
+
 export var metadata = {
   optional: true,
   stage: 1
 };
+
+export function check(node) {
+  return !!node.decorators;
+}
+
+export function ObjectExpression(node, parent, scope, file) {
+  var hasDecorators = false;
+  for (var i = 0; i < node.properties.length; i++) {
+    var prop = node.properties[i];
+    if (prop.decorators) {
+      hasDecorators = true;
+      break;
+    }
+  }
+  if (!hasDecorators) return;
+
+  var mutatorMap = {};
+
+  for (var i = 0; i < node.properties.length; i++) {
+    defineMap.push(mutatorMap, node.properties[i], null, file);
+  }
+
+  var obj = defineMap.toClassObject(mutatorMap);
+  obj = defineMap.toComputedObjectFromClass(obj);
+  return t.callExpression(file.addHelper("create-decorated-object"), [obj]);
+}

src/babel/transformation/transformers/es7/trailing-function-commas.js

@@ -0,0 +1,7 @@
+export var metadata = {
+  stage: 1
+};
+
+export function check() {
+  return false;
+}

src/babel/transformation/transformers/index.js

@@ -1,5 +1,6 @@
 export default {
   "es7.classProperties":                   require("./es7/class-properties"),
+  "es7.trailingFunctionCommas":            require("./es7/trailing-function-commas"),
   "es7.asyncFunctions":                    require("./es7/async-functions"),
   "es7.decorators":                        require("./es7/decorators"),
 

src/babel/transformation/transformers/other/bluebird-coroutines.js

@@ -15,7 +15,7 @@ exports.Function = function (node, parent, scope, file) {
 
   return remapAsyncToGenerator(
     node,
-    t.memberExpression(file.addImport("bluebird", null, true), t.identifier("coroutine")),
+    t.memberExpression(file.addImport("bluebird"), t.identifier("coroutine")),
     scope
   );
 };

src/babel/transformation/transformers/other/regenerator.js

@@ -1,4 +1,4 @@
-import regenerator from "regenerator-babel";
+import regenerator from "regenerator";
 import * as t from "../../../types";
 
 export function check(node) {

src/babel/transformation/transformers/other/runtime/definitions.json

@@ -0,0 +1,99 @@
+{
+  "builtins": {
+    "Symbol": "symbol",
+    "Promise": "promise",
+    "Map": "map",
+    "WeakMap": "weak-map",
+    "Set": "set",
+    "WeakSet": "weak-set"
+  },
+  "methods": {
+    "Array": {
+      "concat": "array/concat",
+      "copyWithin": "array/copy-within",
+      "entries": "array/entries",
+      "every": "array/every",
+      "fill": "array/fill",
+      "filter": "array/filter",
+      "findIndex": "array/find-index",
+      "find": "array/find",
+      "forEach": "array/for-each",
+      "from": "array/from",
+      "includes": "array/includes",
+      "indexOf": "array/index-of",
+      "join": "array/join",
+      "keys": "array/keys",
+      "lastIndexOf": "array/last-index-of",
+      "map": "array/map",
+      "of": "array/of",
+      "pop": "array/pop",
+      "push": "array/push",
+      "reduceRight": "array/reduce-right",
+      "reduce": "array/reduce",
+      "reverse": "array/reverse",
+      "shift": "array/shift",
+      "slice": "array/slice",
+      "some": "array/some",
+      "sort": "array/sort",
+      "splice": "array/splice",
+      "turn": "array/turn",
+      "unshift": "array/unshift",
+      "values": "array/values"
+    },
+    "Object": {
+      "assign": "object/assign",
+      "classof": "object/classof",
+      "define": "object/define",
+      "entries": "object/entries",
+      "freeze": "object/freeze",
+      "getOwnPropertyDescriptor": "object/get-own-property-descriptor",
+      "getOwnPropertyDescriptors": "object/get-own-property-descriptors",
+      "getOwnPropertyNames": "object/get-own-property-names",
+      "getOwnPropertySymbols": "object/get-own-property-symbols",
+      "getPrototypePf": "object/get-prototype-of",
+      "index": "object/index",
+      "isExtensible": "object/is-extensible",
+      "isFrozen": "object/is-frozen",
+      "isObject": "object/is-object",
+      "isSealed": "object/is-sealed",
+      "is": "object/is",
+      "keys": "object/keys",
+      "make": "object/make",
+      "preventExtensions": "object/prevent-extensions",
+      "seal": "object/seal",
+      "setPrototypeOf": "object/set-prototype-of",
+      "values": "object/values"
+    },
+    "RegExp": {
+      "escape": "regexp/escape"
+    },
+    "Function": {
+      "only": "function/only",
+      "part": "function/part"
+    },
+    "Math": {
+      "acosh": "math/acosh",
+      "asinh": "math/asinh",
+      "atanh": "math/atanh",
+      "cbrt": "math/cbrt",
+      "clz32": "math/clz32",
+      "cosh": "math/cosh",
+      "expm1": "math/expm1",
+      "fround": "math/fround",
+      "pot": "math/pot",
+      "imul": "math/imul",
+      "log10": "math/log10",
+      "log1p": "math/log1p",
+      "log2": "math/log2",
+      "sign": "math/sign",
+      "sinh": "math/sinh",
+      "tanh": "math/tanh",
+      "trunc": "math/trunc"
+    },
+    "Date": {
+      "addLocale": "date/add-locale",
+      "formatUTC": "date/format-utc",
+      "format": "date/format"
+    }
+  }
+}

src/babel/transformation/transformers/other/runtime/index.js

@@ -1,23 +1,12 @@
-import core from "core-js/library";
 import includes from "lodash/collection/includes";
-import * as util from  "../../../util";
+import * as util from  "../../../../util";
 import has from "lodash/object/has";
-import * as t from "../../../types";
+import * as t from "../../../../types";
+import definitions from "./definitions";
 
 var isSymbolIterator = t.buildMatchMemberExpression("Symbol.iterator");
 
-var ALIASABLE_CONSTRUCTORS = [
-"Symbol",
-"Promise",
-"Map",
-"WeakMap",
-"Set",
-"WeakSet"
-];
-
-function coreHas(node) {
-  return node.name !== "_" && has(core, node.name);
-}
+const RUNTIME_MODULE_NAME = "babel-runtime";
 
 var astVisitor = {
   enter(node, parent, scope, file) {
@@ -30,13 +19,17 @@ var astVisitor = {
 
       if (!t.isReferenced(obj, node)) return;
 
-      if (!node.computed && coreHas(obj) && has(core[obj.name], prop.name) && !scope.getBindingIdentifier(obj.name)) {
-        this.skip();
-        return t.prependToMemberExpression(node, file.get("coreIdentifier"));
-      }
-    } else if (this.isReferencedIdentifier() && !t.isMemberExpression(parent) && includes(ALIASABLE_CONSTRUCTORS, node.name) && !scope.getBindingIdentifier(node.name)) {
+      if (node.computed) return;
+      if (!has(definitions.methods, obj.name)) return;
+      if (!has(definitions.methods[obj.name], prop.name)) return;
+      if (scope.getBindingIdentifier(obj.name)) return;
+
+      var modulePath = definitions.methods[obj.name][prop.name];
+      return file.addImport(`${RUNTIME_MODULE_NAME}/core-js/${modulePath}`, `${obj.name}$${prop.name}`, true);
+    } else if (this.isReferencedIdentifier() && !t.isMemberExpression(parent) && has(definitions.builtins, node.name) && !scope.getBindingIdentifier(node.name)) {
       // Symbol() -> _core.Symbol(); new Promise -> new _core.Promise
-      return t.memberExpression(file.get("coreIdentifier"), node);
+      var modulePath = definitions.builtins[node.name];
+      return file.addImport(`${RUNTIME_MODULE_NAME}/core-js/${modulePath}`, node.name, true);
     } else if (this.isCallExpression()) {
       // arr[Symbol.iterator]() -> _core.$for.getIterator(arr)
 
@@ -49,10 +42,7 @@ var astVisitor = {
       prop = callee.property;
       if (!isSymbolIterator(prop)) return false;
 
-      return util.template("corejs-iterator", {
-        CORE_ID: file.get("coreIdentifier"),
-        VALUE:   callee.object
-      });
+      return t.callExpression(file.addImport(`${RUNTIME_MODULE_NAME}/core-js/get-iterator`, "getIterator", true), [callee.object]);
     } else if (this.isBinaryExpression()) {
       // Symbol.iterator in arr -> core.$for.isIterable(arr)
 
@@ -61,10 +51,7 @@ var astVisitor = {
       var left = node.left;
       if (!isSymbolIterator(left)) return;
 
-      return util.template("corejs-is-iterator", {
-        CORE_ID: file.get("coreIdentifier"),
-        VALUE:   node.right
-      });
+      return t.callExpression(file.addImport(`${RUNTIME_MODULE_NAME}/core-js/is-iterator`, "isIterable", true), [node.right]);
     }
   }
 };
@@ -79,15 +66,11 @@ exports.Program = function (node, parent, scope, file) {
 
 exports.pre = function (file) {
   file.set("helperGenerator", function (name) {
-    return file.addImport(`babel-runtime/helpers/${name}`, name);
-  });
-
-  file.setDynamic("coreIdentifier", function () {
-    return file.addImport("babel-runtime/core-js", "core");
+    return file.addImport(`${RUNTIME_MODULE_NAME}/helpers/${name}`, name, true);
   });
 
   file.setDynamic("regeneratorIdentifier", function () {
-    return file.addImport("babel-runtime/regenerator", "regeneratorRuntime");
+    return file.addImport(`${RUNTIME_MODULE_NAME}/regenerator`, "regeneratorRuntime", true);
   });
 };
 

src/babel/transformation/transformers/utility/dead-code-elimination.js

@@ -34,6 +34,7 @@ export var IfStatement = {
   exit(node, parent, scope) {
     var consequent = node.consequent;
     var alternate  = node.alternate;
+    var test = node.test;
 
     var evaluateTest = this.get("test").evaluateTruthy();
 

src/babel/traversal/path/evaluation.js

@@ -57,7 +57,7 @@ export function evaluate(): { confident: boolean; value: any } {
     }
 
     if (path.isLiteral()) {
-      if (node.regex && node.value === null) {
+      if (node.regex) {
         // we have a regex and we can't represent it natively
       } else {
         return node.value;

src/babel/traversal/path/index.js

@@ -91,6 +91,9 @@ export default class TraversalPath {
 
     if (this.parentPath.isExpressionStatement() || this.parentPath.isLabeledStatement()) {
       return this.parentPath.insertBefore(nodes);
+    } else if (this.isPreviousType("Expression") || (this.parentPath.isForStatement() && this.key === "init")) {
+      if (this.node) nodes.push(this.node);
+      this.replaceExpressionWithStatements(nodes);
     } else if (this.isPreviousType("Statement")) {
       this._maybePopFromStatements(nodes);
       if (Array.isArray(this.container)) {
@@ -101,15 +104,11 @@ export default class TraversalPath {
       } else {
         throw new Error("We don't know what to do with this node type. We were previously a Statement but we can't fit in here?");
       }
-    } else if (this.isPreviousType("Expression")) {
-      if (this.node) nodes.push(this.node);
-      this.replaceExpressionWithStatements(nodes);
     } else {
       throw new Error("No clue what to do with this node type.");
     }
   }
 
-
   _containerInsert(from, nodes) {
     this.updateSiblingKeys(from, nodes.length);
 
@@ -133,11 +132,24 @@ export default class TraversalPath {
 
   _maybePopFromStatements(nodes) {
     var last = nodes[nodes.length - 1];
-    if (t.isExpressionStatement(last) && t.isIdentifier(last.expression)) {
+    if (t.isExpressionStatement(last) && t.isIdentifier(last.expression) && !this.isCompletionRecord()) {
       nodes.pop();
     }
   }
 
+  isCompletionRecord() {
+    var path = this;
+
+    do {
+      var container = path.container;
+      if (Array.isArray(container) && path.key !== container.length - 1) {
+        return false;
+      }
+    } while (path = path.parentPath && !path.isProgram());
+
+    return true;
+  }
+
   isStatementOrBlock() {
     if (t.isLabeledStatement(this.parent) || t.isBlockStatement(this.container)) {
       return false;
@@ -152,6 +164,13 @@ export default class TraversalPath {
 
     if (this.parentPath.isExpressionStatement() || this.parentPath.isLabeledStatement()) {
       return this.parentPath.insertAfter(nodes);
+    } else if (this.isPreviousType("Expression") || (this.parentPath.isForStatement() && this.key === "init")) {
+      if (this.node) {
+        var temp = this.scope.generateTemp();
+        nodes.unshift(t.expressionStatement(t.assignmentExpression("=", temp, this.node)));
+        nodes.push(t.expressionStatement(temp));
+      }
+      this.replaceExpressionWithStatements(nodes);
     } else if (this.isPreviousType("Statement")) {
       this._maybePopFromStatements(nodes);
       if (Array.isArray(this.container)) {
@@ -159,16 +178,10 @@ export default class TraversalPath {
       } else if (this.isStatementOrBlock()) {
         if (this.node) nodes.unshift(this.node);
         this.container[this.key] = t.blockStatement(nodes);
+        this.replaceExpressionWithStatements(nodes);
       } else {
         throw new Error("We don't know what to do with this node type. We were previously a Statement but we can't fit in here?");
       }
-    } else if (this.isPreviousType("Expression")) {
-      if (this.node) {
-        var temp = this.scope.generateTemp();
-        nodes.unshift(t.expressionStatement(t.assignmentExpression("=", temp, this.node)));
-        nodes.push(t.expressionStatement(temp));
-      }
-      this.replaceExpressionWithStatements(nodes);
     } else {
       throw new Error("No clue what to do with this node type.");
     }
@@ -547,6 +560,9 @@ export default class TraversalPath {
       var binding = this.scope.getBinding(this.node.name);
       if (!binding || !binding.constant) return;
 
+      // todo: take into consideration infinite recursion #1149
+      return;
+
       if (binding.path === this) {
         return this;
       } else {

src/babel/traversal/scope.js

@@ -80,7 +80,7 @@ export default class Scope {
     if (cached && cached.parent === parent) {
       return cached;
     } else {
-      path.setData("scope", this);
+      //path.setData("scope", this);
     }
 
     this.parent = parent;
@@ -237,10 +237,15 @@ export default class Scope {
     var local = this.getOwnBindingInfo(name);
     if (!local) return;
 
+
     if (kind === "param") return;
     if (kind === "hoisted" && local.kind === "let") return;
 
-    if (local.kind === "let" || local.kind === "const" || local.kind === "module" || local.kind === "param") {
+    var duplicate = false;
+    duplicate ||= kind === "let" || kind === "const" || local.kind === "let" || local.kind === "const" || local.kind === "module";
+    duplicate ||= local.kind === "param" && (kind === "let" || kind === "const");
+
+    if (duplicate) {
       throw this.file.errorWithNode(id, messages.get("scopeDuplicateDeclaration", name), TypeError);
     }
   }
@@ -444,7 +449,7 @@ export default class Scope {
     if (path.isLoop()) {
       for (let i = 0; i < t.FOR_INIT_KEYS.length; i++) {
         var node = path.get(t.FOR_INIT_KEYS[i]);
-        if (node.isBlockScoped()) this.registerBinding("let", node);
+        if (node.isBlockScoped()) this.registerBinding(node.node.kind, node);
       }
     }
 
@@ -472,6 +477,15 @@ export default class Scope {
       this.traverse(path.get("body").node, blockVariableVisitor, this);
     }
 
+    // Program, Function - var variables
+
+    if (path.isProgram() || path.isFunction()) {
+      this.traverse(path.node, functionVariableVisitor, {
+        blockId: path.get("id").node,
+        scope:   this
+      });
+    }
+
     // Program, BlockStatement, Function - let variables
 
     if (path.isBlockStatement() || path.isProgram()) {
@@ -490,15 +504,6 @@ export default class Scope {
       this.registerBinding("let", path);
     }
 
-    // Program, Function - var variables
-
-    if (path.isProgram() || path.isFunction()) {
-      this.traverse(path.node, functionVariableVisitor, {
-        blockId: path.get("id").node,
-        scope:   this
-      });
-    }
-
     // Program
 
     if (path.isProgram()) {

src/babel/types/builder-keys.json

@@ -57,7 +57,8 @@
     "id": null,
     "params": null,
     "body": null,
-    "generator": false
+    "generator": false,
+    "async": false
   },
 
   "GenericTypeAnnotation": {

src/babel/types/validators.js

@@ -115,7 +115,8 @@ export function isReferencedIdentifier(node: Object, parent: Object, opts?: Obje
  */
 
 export function isValidIdentifier(name: string): boolean {
-  return isString(name) && esutils.keyword.isIdentifierName(name) && !esutils.keyword.isReservedWordES6(name, true);
+  if (!isString(name) || esutils.keyword.isReservedWordES6(name, true)) return false;
+  return esutils.keyword.isIdentifierNameES6(name);
 }
 
 /**

src/babel/types/visitor-keys.json

@@ -11,8 +11,8 @@
   "CallExpression":            ["callee", "arguments"],
   "CatchClause":               ["param", "body"],
   "ClassBody":                 ["body"],
-  "ClassDeclaration":          ["id", "body", "superClass", "typeParameters", "superTypeParameters", "implements"],
-  "ClassExpression":           ["id", "body", "superClass", "typeParameters", "superTypeParameters", "implements"],
+  "ClassDeclaration":          ["id", "body", "superClass", "typeParameters", "superTypeParameters", "implements", "decorators"],
+  "ClassExpression":           ["id", "body", "superClass", "typeParameters", "superTypeParameters", "implements", "decorators"],
   "ComprehensionBlock":        ["left", "right", "body"],
   "ComprehensionExpression":   ["filter", "blocks", "body"],
   "ConditionalExpression":     ["test", "consequent", "alternate"],
@@ -40,12 +40,12 @@
   "LogicalExpression":         ["left", "right"],
   "MemberExpression":          ["object", "property"],
   "MetaProperty":              ["meta", "property"],
-  "MethodDefinition":          ["key", "value"],
+  "MethodDefinition":          ["key", "value", "decorators"],
   "NewExpression":             ["callee", "arguments"],
   "ObjectExpression":          ["properties"],
   "ObjectPattern":             ["properties", "typeAnnotation"],
   "Program":                   ["body"],
-  "Property":                  ["key", "value"],
+  "Property":                  ["key", "value", "decorators"],
   "RestElement":               ["argument", "typeAnnotation"],
   "ReturnStatement":           ["argument"],
   "SequenceExpression":        ["expressions"],

src/babel/util.js

@@ -55,7 +55,15 @@ export function resolveRelative(loc: string) {
 }
 
 export function list(val: string): Array<string> {
-  return val ? val.split(",") : [];
+  if (!val) {
+    return [];
+  } else if (Array.isArray(val)) {
+    return val;
+  } else if (typeof val === "string") {
+    return val.split(",");
+  } else {
+    return [val];
+  }
 }
 
 export function regexify(val: any): RegExp {
@@ -85,6 +93,21 @@ export function booleanify(val: any): boolean {
   return val;
 }
 
+export function shouldIgnore(filename, ignore, only) {
+  if (only.length) {
+    for (var i = 0; i < only.length; i++) {
+      if (only[i].test(filename)) return false;
+    }
+    return true;
+  } else if (ignore.length) {
+    for (var i = 0; i < ignore.length; i++) {
+      if (ignore[i].test(filename)) return true;
+    }
+  }
+
+  return false;
+}
+
 var templateVisitor = {
   enter(node, parent, scope, nodes) {
     if (t.isExpressionStatement(node)) {

test/acorn/tests-babel.js

@@ -2787,6 +2787,66 @@ test('class Foo { @bar static foo = "bar"; }', {
   features: { "es7.classProperties": true, "es7.decorators": true }
 });
 
+test("var obj = { @foo bar: 'wow' };", {
+  "start": 0,
+  "body": [{
+    "start": 0,
+    "declarations": [{
+      "start": 4,
+      "id": {
+        "start": 4,
+        "name": "obj",
+        "type": "Identifier",
+        "end": 7
+      },
+      "init": {
+        "start": 10,
+        "properties": [{
+          "start": 17,
+          "key": {
+            "start": 17,
+            "name": "bar",
+            "type": "Identifier",
+            "end": 20
+          },
+          "value": {
+            "start": 22,
+            "value": "wow",
+            "raw": "'wow'",
+            "type": "Literal",
+            "end": 27
+          },
+          "kind": "init",
+          "decorators": [{
+            "start": 12,
+            "expression": {
+              "start": 13,
+              "name": "foo",
+              "type": "Identifier",
+              "end": 16
+            },
+            "type": "Decorator",
+            "end": 16
+          }],
+          "type": "Property",
+          "end": 27
+        }],
+        "type": "ObjectExpression",
+        "end": 29
+      },
+      "type": "VariableDeclarator",
+      "end": 29
+    }],
+    "kind": "var",
+    "type": "VariableDeclaration",
+    "end": 30
+  }],
+  "type": "Program",
+  "end": 30
+}, {
+  features: { "es7.decorators": true }
+});
+
 // ES7 export extensions - https://github.com/leebyron/ecmascript-more-export-from
 
 test('export foo, { bar } from "bar";', {
@@ -2940,3 +3000,99 @@ test('export * as foo from "bar";', {
   sourceType: "module",
   features: { "es7.exportExtensions": true }
 });
+
+// ES7: Trailing Function Commas
+
+test("log(n, '=', 2,);", {
+  type: "Program",
+  start: 0,
+  end: 16,
+  body: [{
+    type: "ExpressionStatement",
+    start: 0,
+    end: 16,
+    expression: {
+      type: "CallExpression",
+      callee: {
+        type: "Identifier",
+        name: "log",
+        start: 0,
+        end: 3
+      },
+      arguments: [{
+        type: "Identifier",
+        name: "n",
+        start: 4,
+        end: 5
+      }, {
+        type: "Literal",
+        value: "=",
+        raw: "'='",
+        start: 7,
+        end: 10
+      }, {
+        type: "Literal",
+        raw: "2",
+        value: 2,
+        start: 12,
+        end: 13
+      }]
+    }
+  }]
+}, {
+  ecmaVersion: 7,
+  features: { "es7.trailingFunctionCommas": true }
+});
+
+test("function log(n, op, val,) { }", {
+  type: "Program",
+  start: 0,
+  end: 29,
+  body: [{
+    type: "FunctionDeclaration",
+    id: {
+      type: "Identifier",
+      name: "log",
+      start: 9,
+      end: 12
+    },
+    start: 0,
+    end: 29,
+    expression: false,
+    params: [{
+      type: "Identifier",
+      name: "n",
+      start: 13,
+      end: 14
+    }, {
+      type: "Identifier",
+      name: "op",
+      start: 16,
+      end: 18
+    }, {
+      type: "Identifier",
+      name: "val",
+      start: 20,
+      end: 23
+    }],
+    body: {
+      type: "BlockStatement",
+      start: 26,
+      end: 29,
+      body: []
+    }
+  }]
+}, {
+  ecmaVersion: 7,
+  features: { "es7.trailingFunctionCommas": true }
+});
+
+testFail("log(,);", "Unexpected token (1:4)", {
+  ecmaVersion: 7,
+  features: { "es7.trailingFunctionCommas": true }
+});
+
+testFail("function log(,) { }", "Unexpected token (1:13)", {
+  ecmaVersion: 7,
+  features: { "es7.trailingFunctionCommas": true }
+});

test/acorn/tests-flow.js

@@ -10959,7 +10959,7 @@ var fbTestFixture = {
       }
     },
   },
-    'Bounded Polymorphism': {
+  'Bounded Polymorphism': {
     'class A<T: Foo> {}': {
       type: 'ClassDeclaration',
       id: {

test/acorn/tests-harmony.js

@@ -1714,6 +1714,8 @@ test("([a, , b]) => 42", {
 
 testFail("([a.a]) => 42", "Assigning to rvalue (1:2)", {ecmaVersion: 6});
 
+testFail("console.log(typeof () => {});", "Unexpected token (1:20)", {ecmaVersion: 6});
+
 test("(x=1) => x * x", {
   type: "Program",
   body: [{

test/core/bin.js

@@ -70,6 +70,7 @@ var buildTest = function (binName, testName, opts) {
 
   return function (callback) {
     this.timeout(5000);
+    clear();
     saveInFiles(opts.inFiles);
 
     var args  = [binLoc].concat(opts.args);
@@ -109,11 +110,11 @@ var buildTest = function (binName, testName, opts) {
   };
 };
 
-before(function () {
+var clear = function () {
   if (fs.existsSync(tmpLoc)) rimraf.sync(tmpLoc);
   fs.mkdirSync(tmpLoc);
   process.chdir(tmpLoc);
-});
+};
 
 _.each(fs.readdirSync(fixtureLoc), function (binName) {
   if (binName[0] === ".") return;

test/core/browserify.js

@@ -12,10 +12,7 @@ suite("browserify", function() {
       assert.ok(bundle.length, "bundle output code");
 
       // ensure that the code runs without throwing an exception
-      vm.runInNewContext("var global = this;\n" + bundle, {
-        setInterval: function () {},
-        setTimeout: function () {}
-      });
+      vm.runInNewContext("var global = this;\n" + bundle, {});
       done();
     })
   })

test/core/fixtures/bin/babel/--ignore/in-files/src/bar/index.js

@@ -0,0 +1 @@
+bar;

test/core/fixtures/bin/babel/--ignore/options.json

@@ -0,0 +1,3 @@
+{
+  "args": ["src", "--out-dir", "lib", "--ignore", "src/foo/*"]
+}

test/core/fixtures/bin/babel/--ignore/stdout.txt

@@ -0,0 +1 @@
+src/bar/index.js -> lib/bar/index.js

test/core/fixtures/bin/babel/--only/in-files/src/bar/index.js

@@ -0,0 +1 @@
+bar;

test/core/fixtures/bin/babel/--only/options.json

@@ -0,0 +1,3 @@
+{
+  "args": ["src", "--out-dir", "lib", "--only", "src/bar/*"]
+}

test/core/fixtures/bin/babel/--only/stdout.txt

@@ -0,0 +1 @@
+src/bar/index.js -> lib/bar/index.js

test/core/fixtures/generation/parentheses/arrow-function-object-body/actual.js

@@ -0,0 +1,4 @@
+var foo = arr.map(v => ({
+  x: v.bar,
+  y: v.bar*2
+}));

test/core/fixtures/generation/parentheses/arrow-function-object-body/expected.js

@@ -0,0 +1,4 @@
+var foo = arr.map(v => ({
+  x: v.bar,
+  y: v.bar * 2
+}));

test/core/fixtures/transformation/bluebird-coroutines/class/expected.js

@@ -2,6 +2,8 @@
 
 var _bluebird2 = require("bluebird");
 
+var _bluebird3 = babelHelpers.interopRequireWildcard(_bluebird2);
+
 var Foo = (function () {
   function Foo() {
     babelHelpers.classCallCheck(this, Foo);
@@ -9,7 +11,7 @@ var Foo = (function () {
 
   babelHelpers.createClass(Foo, [{
     key: "foo",
-    value: _bluebird2.coroutine(function* () {
+    value: _bluebird3["default"].coroutine(function* () {
       var wat = yield bar();
     })
   }]);

test/core/fixtures/transformation/bluebird-coroutines/expression/expected.js

@@ -2,6 +2,10 @@
 
 var _bluebird2 = require("bluebird");
 
-var foo = _bluebird2.coroutine(function* () {
+var _bluebird3 = _interopRequireWildcard(_bluebird2);
+
+var _interopRequireWildcard = function (obj) { return obj && obj.__esModule ? obj : { "default": obj }; };
+
+var foo = _bluebird3["default"].coroutine(function* () {
   var wat = yield bar();
 });

test/core/fixtures/transformation/bluebird-coroutines/named-expression/expected.js

@@ -2,9 +2,13 @@
 
 var _bluebird2 = require("bluebird");
 
+var _bluebird3 = _interopRequireWildcard(_bluebird2);
+
 var _bar;
 
-var foo = _bar = _bluebird2.coroutine(function* () {
+var _interopRequireWildcard = function (obj) { return obj && obj.__esModule ? obj : { "default": obj }; };
+
+var foo = _bar = _bluebird3["default"].coroutine(function* () {
   console.log(_bar);
 });
 

test/core/fixtures/transformation/bluebird-coroutines/statement/expected.js

@@ -2,6 +2,10 @@
 
 var _bluebird2 = require("bluebird");
 
-var foo = _bluebird2.coroutine(function* () {
+var _bluebird3 = _interopRequireWildcard(_bluebird2);
+
+var _interopRequireWildcard = function (obj) { return obj && obj.__esModule ? obj : { "default": obj }; };
+
+var foo = _bluebird3["default"].coroutine(function* () {
   var wat = yield bar();
 });

test/core/fixtures/transformation/es6.classes/native-constructors/actual.js

@@ -0,0 +1,10 @@
+class Foo extends Array {
+
+}
+
+class Bar extends Array {
+  constructor() {
+    super();
+    this.foo = "bar";
+  }
+}

test/core/fixtures/transformation/es6.classes/native-constructors/exec.js

@@ -0,0 +1,27 @@
+class Foo extends Array {
+
+}
+
+class Bar extends Array {
+  constructor() {
+    super();
+    this.foo = "bar";
+  }
+}
+
+var foo = new Foo;
+assert.ok(Array.isArray(foo));
+foo.push(1);
+foo.push(2);
+assert.equal(foo[0], 1);
+assert.equal(foo[1], 2);
+assert.equal(foo.length, 2);
+
+var bar = new Bar;
+assert.ok(Array.isArray(bar));
+assert.equal(bar.foo, "bar");
+bar.push(1);
+bar.push(2);
+assert.equal(bar[0], 1);
+assert.equal(bar[1], 2);
+assert.equal(bar.length, 2);

test/core/fixtures/transformation/es6.classes/native-constructors/expected.js

@@ -0,0 +1,35 @@
+"use strict";
+
+var Foo = (function (_Array) {
+  function Foo() {
+    babelHelpers.classCallCheck(this, Foo);
+
+    if (_Array != null) {
+      var _this = new (babelHelpers.bind.apply(_Array, [null].concat(babelHelpers.slice.call(arguments))))();
+
+      _this.__proto__ = Foo.prototype;
+      return _this;
+    }
+
+    return _this;
+  }
+
+  babelHelpers.inherits(Foo, _Array);
+  return Foo;
+})(Array);
+
+var Bar = (function (_Array2) {
+  function Bar() {
+    babelHelpers.classCallCheck(this, Bar);
+
+    var _this2 = new _Array2();
+
+    _this2.__proto__ = Bar.prototype;
+
+    _this2.foo = "bar";
+    return _this2;
+  }
+
+  babelHelpers.inherits(Bar, _Array2);
+  return Bar;
+})(Array);

test/core/fixtures/transformation/es6.constants/loop/actual.js

@@ -0,0 +1,3 @@
+for (const i = 0; i < 3; i = i + 1) {
+  console.log(i);
+}

test/core/fixtures/transformation/es6.constants/loop/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "\"i\" is read-only"
+}

test/core/fixtures/transformation/es6.destructuring/array-unpack-optimisation/actual.js

@@ -8,3 +8,4 @@ var [[a, b, ...c]] = [[1, 2, 3, 4]];
 var [a, b] = [1, 2, 3];
 var [[a, b]] = [[1, 2, 3]];
 var [a, b] = [a, b];
+[a[0], a[1]] = [a[1], a[0]];

test/core/fixtures/transformation/es6.destructuring/array-unpack-optimisation/expected.js

@@ -22,3 +22,7 @@ var b = _ref2[1];
 var _ref3 = [a, b];
 var a = _ref3[0];
 var b = _ref3[1];
+var _temp = [a[1], a[0]];
+a[0] = _temp[0];
+a[1] = _temp[1];
+_temp;

test/core/fixtures/transformation/es6.destructuring/assignment-expression-completion-record/actual.js

@@ -0,0 +1,2 @@
+var x, y;
+[x, y] = [1, 2];

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

@@ -0,0 +1,7 @@
+"use strict";
+
+var x, y;
+var _temp = [1, 2];
+x = _temp[0];
+y = _temp[1];
+_temp;

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

@@ -1,5 +1,5 @@
 "use strict";
 
-var _temp, _temp2;
+var _temp;
 
-console.log((_temp = [123], _temp2 = babelHelpers.slicedToArray(_temp, 1), x = _temp2[0], _temp));
+console.log((_temp = [123], x = _temp[0], _temp));

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

@@ -1,4 +1,5 @@
 var z = {};
 var { ...x } = z;
 var { x, ...y } = z;
+var { [x]: x, ...y } = z;
 (function({ x, ...y }) { })

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

@@ -4,6 +4,8 @@ var z = {};
 var x = babelHelpers.objectWithoutProperties(z, []);
 var x = z.x;
 var y = babelHelpers.objectWithoutProperties(z, ["x"]);
+var x = z[x];
+var y = babelHelpers.objectWithoutProperties(z, [x]);
 
 (function (_ref) {
   var x = _ref.x;

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

@@ -1,6 +1,7 @@
 "use strict";
 
-foo.foo = 1;
-foo.bar = 2;
+var _ref = [1, 2];
+foo.foo = _ref[0];
+foo.bar = _ref[1];
 
 ;

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

@@ -2,13 +2,16 @@
 
 var _classCallCheck = function (instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } };
 
-module.exports = foo;
-module.exports = 42;
-module.exports = {};
-module.exports = [];
-module.exports = foo;
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports["default"] = foo;
+exports["default"] = 42;
+exports["default"] = {};
+exports["default"] = [];
+exports["default"] = foo;
 
-module.exports = function () {};
+exports["default"] = function () {};
 
 var _default = (function () {
   var _class = function _default() {
@@ -18,7 +21,7 @@ var _default = (function () {
   return _class;
 })();
 
-module.exports = _default;
+exports["default"] = _default;
 
 function foo() {}
 
@@ -26,5 +29,6 @@ var Foo = function Foo() {
   _classCallCheck(this, Foo);
 };
 
-module.exports = Foo;
-module.exports = foo;
+exports["default"] = Foo;
+exports["default"] = foo;
+module.exports = exports["default"];