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Changelog

Tags:

  • πŸ’₯ [Breaking Change]
  • πŸ‘“ [Spec Compliancy]
  • πŸš€ [New Feature]
  • πŸ› [Bug Fix]
  • πŸ“ [Documentation]
  • 🏠 [Internal]
  • πŸ’… [Polish]

Note: Gaps between patch versions are faulty, broken or test releases.

See CHANGELOG - 6to5 for the pre-4.0.0 version changelog.

6.21.1 (2016-12-17)

πŸ› Bug Fix

  • babel-helper-builder-react-jsx, babel-plugin-transform-react-jsx
    • #5015 Revert the introduction of a new error message that ended up introducing its own error (@loganfsmyth)

6.21.0 (2016-12-16)

πŸš€ New Feature

Exposes raw mappings when source map generation is enabled. To avoid the cost of source map generation for consumers of the raw mappings only, .map is changed to a getter that generates the source map lazily on first access.

Raw mappings can be useful for post-processing source maps more efficiently by avoiding one decoding/encoding cycle of the b64 vlq mappings. This will be used in the React Native packager.

let generator = require("babel-generator");
let generated = generator(ast, { sourceMaps: true }, sources);

// generated.rawMappings
[
  {
    name: undefined,
    generated: { line: 1, column: 0 },
    source: "inline",
    original: { line: 1, column: 0 }
  },
  ...
]

πŸ› Bug Fix

  • babel-generator, babel-plugin-transform-flow-comments, babel-plugin-transform-flow-strip-types
    • #4872 Print Flow optional & type annotations in function params with defaults. (@danharper)

Works with generator, transform-flow-comments, flow-strip-types.

function foo(numVal: number = 2) {}
  • babel-generator, babel-plugin-transform-es2015-modules-amd, babel-plugin-transform-es2015-modules-umd
let blockStatement = t.blockStatement(
  [],
  [t.directive(t.directiveLiteral("use strict"))]
);
  • babel-generator, babel-helper-builder-react-jsx, babel-plugin-transform-react-jsx, babel-types

Will still error with Spread children are not supported.

<div>{...this.props.children}</div>;
  • babel-plugin-transform-es2015-block-scoping, babel-plugin-transform-react-constant-elements, babel-traverse

When multiple declarators are present in a declaration, we want to insert the constant element inside the declaration rather than placing it before because it may rely on a declarator inside that same declaration.

function render() {
  const bar = "bar", renderFoo = () => <foo bar={bar} baz={baz} />, baz = "baz";

  return renderFoo();
}

When block scoped variables caused the block to be wrapped in a closure, the variable bindings remained in parent function scope, which caused the JSX element to be hoisted out of the closure.

function render(flag) {
  if (flag) {
    let bar = "bar";

    [].map(() => bar);

    return <foo bar={bar} />;
  }

  return null;
}
  • babel-plugin-transform-es2015-parameters

Was erroring if the rest parameter shared the same name as a default identifier for a param, needed to be deopt'd.

const a = 1;
function rest(b = a, ...a) {
  assert.equal(b, 1);
}
rest(undefined, 2)
  • babel-plugin-transform-es2015-for-of, babel-traverse
myLabel: //woops
for (let a of b) {
  continue myLabel;
}

πŸ“ Documentation

  • Other
  • babel-plugin-transform-runtime
    • #4991 make installing runtime/transform-runtime clearer [skip ci]. (@hzoo)
  • babel-plugin-transform-es2015-unicode-regex

🏠 Internal

  • babel-helper-transform-fixture-test-runner, babel-plugin-syntax-trailing-function-commas
    • #4999 babel-helper-transform-fixture-test-runner: pass require as a global. (@hzoo)

Allows running require() in exec.js tests like for babel/babel-preset-env#95

  • Other
    • #5005 internal: don't run watch with the test env (skip building with code …. (@hzoo)

Committers: 9

v6.20.3 (2016-12-08)

😒 Regression

  • babel-plugin-transform-async-to-generator

v6.20.2 (2016-12-08)

😒 Regression

Issue: https://github.com/babel/babel/issues/4972 again. Fixed by reverting part of the original PR in babel/babel#4883.

v6.20.1 (2016-12-08)

😒 Regression

Issue: https://github.com/babel/babel/issues/4972

The way that babel/babel#4883 changed visiting SpreadProperty (which didn't need to modified) caused an infinite loop. Added path.stop which ended up not fixing it correctly.

v6.20.0 (2016-12-08)

If you missed it, please check out our latest blog post: The State of Babel. Talks about where we can possibly move forward as a project and how you can help!


You've probably seen this more than a few times and had no idea what it meant...

[BABEL] Note: The code generator has deoptimised the styling of "app.js" as it exceeds the max of "100KB".

Generating code used to get really slow as file size increased. We've mostly fixed that, but we still automatically fall back to compact output on large files. We're going to bump the limit to 500KB and if there aren't issues just remove it.


Ben Newman, @benjamn: wrote Regenerator while at Facebook. It used a bunch of other libraries such as ast-types but has now been rewritten as a standalone Babel plugin (also thanks to Sebastian's previous work in facebook/regenerator#222). We're also moving the implementation of Regenerator back into the original repository since Ben is the creator/maintainer.

πŸš€ New Feature

  • babel-traverse
    • #4876 Add getBindingIdentifierPaths/getOuterBindingIdentifierPaths. (@boopathi)

Returns Array<Path> rather than Array<Node>.

  • path.getBindingIdentifierPaths()
  • path.getOuterBindingIdentifierPaths()
traverse(parse(`
  var a = 1, {b} = c, [d] = e, function f() {};
`), {
  VariableDeclaration(path) {
    let nodes = path.getBindingIdentifiers(); // a, d, b
    let paths = path.getBindingIdentifierPaths();
  },
  FunctionDeclaration(path) {
    let outerNodes = path.getOuterBindingIdentifiers(); // f
    let outerPaths = path.getOuterBindingIdentifierPaths();
  }
});
  • babel-code-frame
    • #4913 Add forceColor option to babel-code-frame. (@Timer)

Forcibly syntax highlight the code as JavaScript (for non-terminals); overrides highlightCode. For facebookincubator/create-react-app#1101

Usage

const result = codeFrame(rawLines, lineNumber, colNumber, {
  forceColor: true
});

πŸ› Bug Fix

  • babel-plugin-transform-es2015-block-scoping
    • #4880 Add (and fix) failing test of function parameter bindings in a catch block. (@benjamn)

In

try {
  foo();
} catch (x) {
  function harmless(x) {
    return x;
  }
}

Correct Out

try {
  foo();
} catch (x) {
  var harmless = function (x) {
    return x;
  };
}
  • babel-helper-remap-async-to-generator, babel-plugin-transform-async-generator-functions, babel-plugin-transform-async-to-generator
// both length's should be 0
const foo = (...args) => { }
console.log(foo.length)  // 0
const asyncFoo = async (...args) => { }
console.log(asyncFoo.length)  // 0
  • babel-generator, babel-types

Relevant for webpack 2 support of Import. Just allows Babel to print it correctly.

import("module.js");
  • babel-plugin-transform-object-rest-spread
function a5({a3, b2: { ba1, ...ba2 }, ...c3}) {}
  • babel-traverse
    • #4875 Fix path.evaluate for references before declarations. (@boopathi)
// should deopt if ids are referenced before the bindings
var a = b + 2; var b = 2 + 2;
  • babel-core, babel-generator, babel-helper-transform-fixture-test-runner, babel-plugin-transform-object-rest-spread
    • #4858 Fix bug + Generate test fixtures if no expected.js. (@hzoo)
  • babel-types

πŸ’… Polish

πŸ“ Documentation

🏠 Internal

  • babel-plugin-transform-regenerator
    • #4881 Use regenerator-transform to implement babel-plugin-transform-regenerator. (@benjamn)
  • babel-traverse
  • babel-polyfill
  • babel-runtime
    • #4877 Upgrade regenerator-runtime to version 0.10.0. (@benjamn)
  • babel-plugin-syntax-trailing-function-commas
  • babel-helper-fixtures
  • babel-core, babel-traverse
  • babel-generator

Committers: 17

v6.19.0 (2016-11-16)

πŸš€ New Feature

  • babel-plugin-transform-object-rest-spread
    • #4755 Make the plugin work standalone with parameters/destructuring plugins. (@hzoo)

This rewrite fixes a long standing issue where the object-rest-spread plugin was depending on 2 other plugins to compile RestProperty. This is important given the assumption that plugins should be independent and is vital for the use of babel-preset-env since new environments support destructuring natively.

RestProperty

  • Parameters
function a({ b, ...c }) {}
  • VariableDeclaration
const { a, ...b } = c;
  • ExportNamedDeclaration
export var { a, ...b } = c;
  • CatchClause
try {} catch ({a, ...b}) {}
  • AssignmentExpression
({a, ...b} = c);
  • ForXStatement
for ({a, ...b} of []) {}

SpreadProperty

  • ObjectExpression
var a = { ...b, ...c }
  • babel-plugin-transform-class-properties
    • #4544 Greater spec compliance for class properties with the new spec option. (@motiz88)

Usage

{
  "plugins": [
    ["transform-class-properties", {
      "spec": true
    }]
  ]
}
  • Class properties are compiled to use Object.defineProperty
  • Static fields are now defined even if they are not initialized

In

class Foo {
  static bar;
}

Out

var Foo = function Foo() {
  babelHelpers.classCallCheck(this, Foo);
};

Object.defineProperty(Foo, "bar", {
  enumerable: true,
  writable: true,
  value: undefined
});
  • babel-traverse

We've added 2 similar "ancestry" path methods to path.findParent:

path.isAncestor/path.isDescenant

Usage:

let programPath, numberPath;
traverse(ast, {
  Program(path) { programPath = path; },
  NumberPath(path) { numberPath = path; },
});

programPath.isAncestor(numberPath); // true
numberPath.isDescendant(programPath); // true
  • #4835 Add clearCache and clearPath as separate APIs under traverse. (@boopathi)

Usage:

traverse.clearCache(); // clears both path's and scope cache
traverse.clearCache.clearPath();
traverse.clearCache.clearScope();
  • babel-generator
    • #4827 Add jsonCompatibleStrings option to generator. (@kangax)

Usage:

{
  "generatorOpts": {
    "jsonCompatibleStrings": true // defaults to false
  }
}

Set to true for the generator to use jsesc with "json": true. This will make it print "\u00A9" vs. "Β©";

Usage:

{
  "generatorOpts": {
    "flowCommaSeparator": true // defaults to false
  }
}

Currently there are 2 supported syntaxes (, and ;) in Flow Object Types. The use of commas is in line with the more popular style and matches how objects are defined in Javascript, making it a bit more natural to write.

var a: { param1: number; param2: string }
var a: { param1: number, param2: string }
  • babel-types
    • #3553 Start babel-types tests, add isNodesEquivalent. (@hzoo)

t.isNodesEquivalent

Usage:

assert(t.isNodesEquivalent(parse("1 + 1"), parse("1+1")) === true);
  • babel-plugin-transform-es2015-modules-systemjs
    • #4789 Support import() as contextual import in system module format. (@guybedford)

Support stage-2 import() in systemjs.

It does not compile by default; you'll want to add the stage-2 preset or explicitly include babel-plugin-syntax-dynamic-import.

export function lazyLoadOperation () {
  return import('./x')
  .then(function (x) {
    x.y();
  });
}

πŸ› Bug Fix

  • babel-generator

Will print the shorter of the NumericLiterals if using the minified option.

Input

5e1;
5e4;

Output

50;
5e4;
  • babel-plugin-transform-es2015-modules-systemjs
    • #4832 Fix system transformer to ensure consistent modules iteration. (@guybedford)

Fixes inconsistent modules iteration for numeric imports

import "2"; // should be imported first
import "1"; // second
  • babel-plugin-transform-es2015-destructuring, babel-plugin-transform-react-constant-elements
    • #4813 Fix binding kind of destructured variables.. (@STRML)

Fixes an issue with destructuring parameters being hoisted incorrectly.

Input

function render({ text }) {
  return () => (<Component text={text} />);
}

Output

function render(_ref) {
  let text = _ref.text;
  var _ref2 = <Component text={text} />;
  return () => _ref2;
}

πŸ“ Documentation

🏠 Internal

  • babel-plugin-transform-async-to-generator
  • Other
    • #4807 Chore: FLOW command in makefile and logic in .travis.yml(issue#4710).. (@sstern6)

Committers: 10

v6.18.2 (2016-11-01)

Weird publishing issue with v6.18.1, same release.

πŸ› Bug Fix

  • babel-core

The error message was actually invalid!

Invalid:
  { "presets": [{ "option": "value" }] }
Valid:
  {
    "presets": [
      ["presetName", { "option": "value" }] // the preset should be wrapped in `[ ]`
    ]
  }

🏠 Internal

  • babel-helper-fixtures, babel-helper-transform-fixture-test-runner
    • #4797 Allow relative paths in babelrc options in options.json. (@hzoo)
  • Other
  • babel-plugin-transform-async-to-generator
    • #4793 Fix async-to-generator/object-method-with-arrows line endings. (@jridgewell)

Commiters: 4

v6.18.1 (2016-11-01)

Weird publishing issue with v6.18.1, re-released as v6.18.2.

v6.18.0 (2016-10-24)

πŸš€ New Feature

  • babel-generator, babel-plugin-transform-flow-strip-types
    • #4697 Add variance node type and generate property variance annotations. (@samwgoldman)

Check out the blog post and flow docs for more info:

type T = { +p: T };
interface T { -p: T };
declare class T { +[k:K]: V };
class T { -[k:K]: V };
class C2 { +p: T = e };
  • babel-core, babel-traverse
    • #4746 Support ObjectExpression in static path evaluation. (@motiz88)
// in
{['a' + 'b']: 10 * 20, 'z': [1, 2, 3]}
// out
{ab: 200, z: [1, 2, 3]}
  • babel-plugin-syntax-dynamic-import, babel-preset-stage-2
    • #4699 [import()] Initial support for dynamic-import. (@kesne)

Parser support was added in https://github.com/babel/babylon/releases/tag/v6.12.0.

Just the plugin to enable it in babel.

// install
$ npm install babel-plugin-syntax-dynamic-import --save-dev

or use the new parserOpts

// .babelrc
{
  "parserOpts": {
    "plugins": ['dynamicImport']
  }
}
  • babel-helper-builder-react-jsx, babel-plugin-transform-react-jsx

Previously we added a useBuiltIns for object-rest-spread so that it use the native/built in version if you use a polyfill or have it supported natively.

This change just uses the same option from the plugin to be applied with spread inside of jsx.

// in
var div = <Component {...props} foo="bar" />
// out
var div = React.createElement(Component, Object.assign({}, props, { foo: "bar" }));
  • babel-generator, babel-traverse, babel-types

EmptyTypeAnnotation

Added in flow here and in babylon here.

function f<T>(x: empty): T {
  return x;
}
f(); // nothing to pass...
  • babel-traverse
    • #4758 Make getBinding ignore labels; add Scope#getLabel, Scope#hasLabel, Scope#registerLabel. (@kangax)

Track LabeledStatement separately (not part of bindings).

πŸ› Bug Fix

Will give examples of code that was fixed below

  • babel-plugin-transform-react-inline-elements, babel-traverse
    • #4765 Don't treat JSXIdentifier in JSXMemberExpression as HTML tag. Closes #4027. (@DrewML)
// issue with imported components that were JSXMemberExpression
import { form } from "./export";

function ParentComponent() {
  return <form.TestComponent />;
}
  • babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-react-inline-elements
    • #4763 Handle remapping of JSXIdentifier to MemberExpression in CommonJS transform. Closes #3728. (@DrewML)
import { Modal } from "react-bootstrap";
export default CustomModal = () => <Modal.Header>foobar</Modal.Header>;
  • babel-plugin-transform-es2015-for-of
if ( true ) {
  loop: for (let ch of []) {}
}
  • babel-core
    • #4502 Make special case for class property initializers in shadow-functions. (@motiz88)
class A {
  prop1 = () => this;
  static prop2 = () => this;
  prop3 = () => arguments;
}
  • #4631 fix(shouldIgnore): filename normalization should be platform sensitive. (@rozele)
    • babel-helper-remap-async-to-generator, babel-plugin-transform-async-generator-functions
  • #4719 Fixed incorrect compilation of async iterator methods. (@Jamesernator)
// in
class C {
  async *g() { await 1; }
}
// out
class C {
  g() { // was incorrectly outputting the method with a generator still `*g(){`
    return _asyncGenerator.wrap(function* () {
      yield _asyncGenerator.await(1);
    })();
  }
}
  • babel-plugin-check-es2015-constants, babel-plugin-transform-es2015-destructuring, babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-es2015-parameters
    • #4690 Consolidate contiguous var declarations in destructuring transform. (@motiz88)
// was wrapping variables in an IIFE incorrectly
for ( let i = 0, { length } = list; i < length; i++ ) {
    console.log( i + ': ' + list[i] )
}
  • babel-plugin-transform-es2015-parameters
    • #4666 Fix error when constructor default arg refers to self or own static property. (@danharper)
// was producing invalid code
class Ref {
  static nextId = 0
  constructor(id = ++Ref.nextId, n = id) {
    this.id = n
  }
}

assert.equal(1, new Ref().id)
assert.equal(2, new Ref().id)
  • #4674 Handle side effects correctly in rest params index expressions (#4348). (@motiz88)
function first(...values) {
    let index = 0;
    return values[index++]; // ++ was happening twice
}

console.log(first(1, 2));
  • babel-plugin-transform-es2015-block-scoping
    • #4669 Fix block scoping transform for declarations in labeled statements. (@motiz88)
let x = 10;
if (1)
{
    ca: let x = 20;
}
  • babel-helper-explode-assignable-expression, babel-plugin-transform-exponentiation-operator
    • #4672 Avoid repeating impure (template) literals when desugaring **= (#4403). (@motiz88)
a[`${b++}`] **= 1;
  • #4642 Exclude super from being assign to ref variable. (@danez)
    • babel-plugin-transform-es2015-shorthand-properties, babel-plugin-transform-flow-comments, babel-plugin-transform-flow-strip-types
foo = {
  bar() {
    return super.baz **= 12;
  }
}
  • #4670 Retain return types on ObjectMethods in transform-es2015-shorthand-properties. (@danharper)
// @flow
var obj = {
  method(a: string): number {
    return 5 + 5;
  }
};
  • babel-helper-define-map, babel-plugin-transform-es2015-classes, babel-plugin-transform-flow-comments, babel-plugin-transform-flow-strip-types
// @flow
class C {
  m(x: number): string {
    return 'a';
  }
}

πŸ’… Polish

  • babel-plugin-check-es2015-constants, babel-plugin-transform-es2015-destructuring, babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-es2015-parameters
    • #4690 Consolidate contiguous var declarations in destructuring transform. (@motiz88)
// in
const [a, b] = [1, 2];
// out
var a = 1,
    b = 2;
  • babel-plugin-transform-es2015-parameters
// was outputting an extra `index++ + 0`
function first(...values) {
  var index = 0;
  return values[index++];
}
  • babel-generator
    • #4646 Change babel-generator to output boolean instead of bool for the BooleanTypeAnnotation AST node. (@existentialism)
var a: Promise<boolean>[];
// instead of
var a: Promise<bool>[];
  • babel-core
    • #4685 Better error messaging when preset options are given without a corresponding preset. (@kaicataldo)

We've had a few reports of users not wrapping a preset in [] when passing in options so we added an extra error message for this.

ReferenceError: [BABEL] /test.js: Unknown option: base.loose2. Check out http://babeljs.io/docs/usage/options/ for more information about options.

A common cause of this error is the presence of a configuration options object without the corresponding preset name. Example:

Invalid:
  `{ presets: [{option: value}] }`
Valid:
  `{ presets: ["pluginName", {option: value}] }`

For more detailed information on preset configuration, please see http://babeljs.io/docs/plugins/#pluginpresets-options.

Documentation

So that our MIT License shows up.

🏠 Internal

It's a one-time use tool (helpful after the initial release when upgrading from v5 to v6) that doesn't need to be a part of babel-cli. We'll publish it as a standalone package it someone asks for it.

  • Other
  • babel-traverse, babel-types
  • babel-cli, babel-core, babel-helper-fixtures, babel-register
  • babel-helper-transform-fixture-test-runner
    • #4735 Automatically generate missing expected.js fixtures. (@motiz88)
    • #4664 πŸš€ Update chai to version 3.0.0. (@danez)
  • babel-cli, babel-code-frame, babel-core, babel-generator, babel-helper-transform-fixture-test-runner, babel-preset-es2015, babel-template, babel-traverse
    • #4734 Change usage of "suite"/"test" in unit-tests to "describe"/"it". (@DrewML)
  • babel-cli, babel-code-frame, babel-core, babel-generator, babel-plugin-transform-es2015-modules-commonjs, babel-preset-es2015, babel-template, babel-traverse
    • #4732 Run ESLint on test files, and fix lint errors in test files.. (@DrewML)
  • babel-cli, babel-core
  • babel-cli, babel-core, babel-plugin-transform-es2015-modules-systemjs, babel-preset-es2015
    • #4721 update eslint-config, fixes, add commands. (@hzoo)
  • babel-register
    • #4660 πŸš€ Update home-or-tmp to version 2.0.0. (@danez)
  • babel-cli
  • babel-core
  • babel-generator
    • #4652 πŸš€ Update detect-indent to version 4.0.0. (@danez)
  • babel-traverse
    • #4651 πŸš€ Update globals to version 9.0.0. (@danez)

Commiters: 17

v6.17.0 (2016-10-01)

πŸ‘“ Spec Compliancy

  • babel-preset-stage-2, babel-preset-stage-3

https://github.com/tc39/proposals/commit/96f8d79dac33575e24f6ac3ec2082efe75d519ba

Specification repo: https://github.com/tc39/proposal-async-iteration

Asynchronous Iteration was already added in 6.16.0 under stage-2 but it was moved to stage-3 at the latest TC-39 meeting.

// async generator syntax
async function* agf() {}
// for-await statement
async function f() {
  for await (let x of y) {
    g(x);
  }
}

To use it as a standalone plugin:

{
  "plugins": ["transform-async-generator-functions"]
}

With the stage-3 preset (or below):

{
  "presets": ["stage-3"]
}
  • #4611 Move object-rest-spread to stage-3. (@hzoo)

Similarly, object-rest-spread is now also at stage-3.

https://twitter.com/sebmarkbage/status/781564713750573056 https://github.com/tc39/proposals/commit/142ac3ce7f3f56989800260f029b76afe4a02e57

// Rest properties
let { x, y, ...z } = { x: 1, y: 2, a: 3, b: 4 };
console.log(x); // 1
console.log(y); // 2
console.log(z); // { a: 3, b: 4 }

// Spread properties
let n = { x, y, ...z };
console.log(n); // { x: 1, y: 2, a: 3, b: 4 }

To use it as a standalone plugin:

{
  "plugins": ["transform-object-rest-spread"]
}

With the stage-3 preset (or below):

{
  "presets": ["stage-3"]
}

πŸš€ New Feature

  • babel-generator

References:

Adds a retainFunctionParens to babel-generator. This option will retain the parentheses around an IIFE.

// parens are stripped without the option
__d('x', (function () {}));

πŸ› Bug Fix

  • babel-core
    • #4635 Forward bound shadowed function when hoisting identifiers. (@danez)
    • #4620 Resolve presets with named exports correctly. (@danez)
  • babel-generator
    • #4633 Fixed babel/babel#4632 - missing parentheses around yield expression …. (@bjouhier)
  • babel-plugin-transform-es2015-parameters
    • #4636 Fix rest parameters with flow type casting. (@danez)
  • babel-plugin-transform-flow-comments
    • #4623 Fix regression in transform-flow-comments for class properties. (@danharper)

First PR!

v6.16.0 (2016-09-28)

Babel 6.16: Happy 2nd Birthday πŸŽ‚!

πŸ‘“ Spec Compliancy

  • babel-core, babel-generator, babel-helper-remap-async-to-generator, babel-helpers, babel-plugin-transform-async-generator-functions, babel-types, babel-preset-stage-2, ...
    • #3473 via #4576 Implement support for async generator functions and for-await statements. (@zenparsing)

This change implements the async iteration proposal, currently at stage 2 (and pushing to stage 3 at the current TC-39 meeting). It includes the following features:

  • Transforms async generator functions (async function* g() { }) to wrapped generator functions, similar to the current async-to-generator transform.
async function* agf() {
  this;
  await 1;
  yield 2;
  return 3;
}
  • Transforms for-await statements into for loops containing yield expressions.
async function f() {
  for await (let x of y) {
    g(x);
  }
}

Example Usage

async function* genAnswers() {
  var stream = [ Promise.resolve(4), Promise.resolve(9), Promise.resolve(12) ];
  var total = 0;
  for await (let val of stream) {
    total += await val;
    yield total;
  }
}

function forEach(ai, fn) {
  return ai.next().then(function (r) {
    if (!r.done) {
      fn(r);
      return forEach(ai, fn);
    }
  });
}

var output = 0;
return forEach(genAnswers(), function(val) { output += val.value })
.then(function () {
  assert.equal(output, 42);
});
  • babel-core, babel-generator, babel-plugin-transform-class-properties, babel-template, babel-traverse, babel-types

Parser support was added in babylon@6.11.0 with babel/babylon#121

// Example
class Foo {
  [x]
  ['y']
}

class Bar {
  [p]
  [m] () {}
}
  • babel-generator
    • #3702 flow plugin: generate exact object type annotations. (@bhosmer)

Parser support was added in babylon@6.10.0 with babel/babylon#104

// Example
var a : {| x: number, y: string |} = { x: 0, y: 'foo' };

πŸš€ New Feature

  • babel-core, babel-generator
    • #3561 babel-core: add options for different parser/generator. (@hzoo)

Babel will now also take the options: parserOpts and generatorOps (as objects).

parserOpts will pass all properties down to the default babylon parser. You can also pass a parser option to substitute for a different parser.

This will allow passing down any of babylon's options:

{
  "parserOpts": {
    "allowImportExportEverywhere": true,
    "allowReturnOutsideFunction": true,
    "sourceType": "module",
    "plugins": ["flow"]
  }
}

Another use case (the main reason for doing this), is to be able to use recast with Babel.

{
  "parserOpts": {
    "parser": "recast"
  },
  "generatorOpts": {
    "generator": "recast"
  }
}
  • babel-core
    • #4542 Add support for preset organization shortcuts. (@nkt)
{
  presets: ["@org/babel-preset-name"], // actual package
  presets: ["@org/name"] // shorthand name
}
  • babel-plugin-transform-object-rest-spread
    • #4491 object rest spread useBuiltIns option. (@hzoo)

useBuiltIns - Do not use Babel's helper's and just transform to use the built-in method (Disabled by default).

{
  "plugins": [
    ["transform-object-rest-spread", { "useBuiltIns": true }]
  ]
}

// source
z = { x, ...y };
// compiled
z = Object.assign({ x }, y);
  • babel-code-frame
    • #4561 babel-code-frame: add options for linesBefore, linesAfter. (@hzoo)

babel-code-frame is a standalone package that we use in Babel when reporting errors.

Now there is an option to specify the number of lines above and below the error

  1 | class Foo {
> 2 |   constructor()
    |                ^
  3 | }
  • babel-core, babel-preset-es2015, babel-preset-es2016, babel-preset-es2017, babel-preset-latest, babel-preset-react, babel-preset-stage-0, babel-preset-stage-1, babel-preset-stage-2, babel-preset-stage-3

We previously made presets with commonjs exports

module.exports = {
  plugins: [
    require("babel-plugin-syntax-trailing-function-commas")
  ]
};

Now you can use export default as well

import transformExponentiationOperator from "babel-plugin-transform-exponentiation-operator";
export default {
  plugins: [
    transformExponentiationOperator
  ]
};

πŸ› Bug Fix

  • babel-helpers, babel-plugin-transform-es2015-typeof-symbol
// `typeof Symbol.prototype` should be 'object'
typeof Symbol.prototype === 'object'
  • babel-cli

Fix an issue with defaults not being overidden. This was causing options like comments: false not to work correctly.

  • #4508 Support custom ports for V8 --inspect. (@andykant)
  • #4562 Fixes #2299: Prevent REPL from printing implicit 'use strict'. (@hzoo)
    • babel-plugin-transform-es2015-function-name, babel-traverse
  • #4524 Fix default export with arrows and function naming. (@danharper)
// wasn't exporting correctly before
export default ({ onClick }) => {
  return <div onClick={() => onClick()}></div>;
}
  • babel-plugin-transform-es2015-modules-commonjs
    • #4511 Fix UpdateExpression handling in es2015-modules-commonjs, resolve #4462. (@motiz88)
    • #4518 fix default exported classes without a name. (@danez)
export default class {};
// wasn't correctly transforming to
exports["default"] = class {}
// with the es3-tranforms
  • babel-plugin-transform-flow-strip-types, babel-types
    • #4521 Fix striping of typeParameters from arrow functions. (@danez)
// <X> wasn't stripped out
const find = <X> (f: (x:X) => X, xs: Array<X>): ?X => (
  xs.reduce(((b, x) => b ? b : f(x) ? x : null), null)
)
  • babel-generator, babel-plugin-transform-flow-comments
  • babel-register
    • #3685 Allow overwritting of sourceRoot. (@danez)
    • #4577 babel-register: update source-map-support to latest. (@MoOx)
  • babel-core
  • babel-traverse
  • babel-plugin-transform-es2015-destructuring
    • #4552 Fix destructuring evaluation with call expressions. (@danez)

We noticed that we can not make this optimizations if there are function calls or member expressions on the right hand side of the assignment since the function call or the member expression (which might be a getter with side-effect) could potentially change the variables we are assigning to.

[x, y] = [a(), obj.x];
// was tranforming to
x = a();
y = obj.x;
// now transforms to 
var _ref = [a(), obj.x];
x = _ref[0];
y = _ref[1];
  • babel-types
    • #4587 Prevent flow-strip-types/flow-comments from removing entire ClassProperty. (@danharper)

πŸ’… Polish

  • babel-code-frame
    • #4579 babel-code-frame: Highlight strings with green (not red). (@lydell)
    • #4572 Improve syntax highlighting colors. (@lydell)

Before

screen shot 2016-09-27 at 11 12 47 am

After

screen shot 2016-09-27 at 3 50 02 pm

  • babel-core
    • #4517 If loading a preset fails, show its name/path (#4506). (@motiz88)
  • babel-helper-replace-supers
  • babel-generator
  • babel-core, babel-plugin-transform-es2015-arrow-functions, babel-plugin-transform-es2015-destructuring, babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-es2015-parameters
  • babel-core, babel-helpers
    • #3653 Removed unnecessary 'return' statements. (@ksjun)

🏠 Internal

Cleanup tests, remove various unused dependencies, do not run CI with only readme changes.

  • babel-plugin-transform-es2015-modules-amd, babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-es2015-modules-umd
  • babel-generator, babel-plugin-transform-es2015-modules-amd, babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-es2015-modules-systemjs, babel-plugin-transform-es2015-modules-umd, babel-plugin-transform-flow-strip-types
  • babel-plugin-transform-es2015-function-name
  • babel-plugin-transform-es2015-parameters, babel-traverse
    • #4519 Replace phabricator tickets with github ones in code comments. (@danez)
  • babel-polyfill
    • #3694 Use plain js to do the pre/postpublish for the polyfill. (@danez)
  • babel-preset-es2015
  • babel-plugin-transform-regenerator
  • babel-code-frame
    • #3699 babel-code-frame: babel-runtime not necessary. (@hzoo)
    • #3696 Satisfy the "space-infix-ops" eslint rule. (@gigabo)
  • babel-helper-transform-fixture-test-runner
    • #4560 Remove unused dependency babel-register. (@danez)
    • #3669 Do not include babel-register in test helper. (@danez)
  • Other

Commiters: 20

First PRs!

v6.15.0 (2016-08-31)

#3612 The main change is an option to transform-runtime for a custom path which will be used in create-react-app. Also some bug fixes.

{
  "plugins": ["transform-runtime", {
    "moduleName": "my-custom-babel-runtime"
  }]
}

#3689 Adds a preserveComments option to babel-template.

It's @ben-eb, @d4rkr00t, and @ryb73 first PRs!

New Feature

  • babel-plugin-transform-runtime
  • babel-template, babel-traverse, babel-types
    • #3689 Add support for preserving comments in babel-template. (@ben-eb)

Bug Fix

  • babel-plugin-transform-es2015-block-scoping
  • babel-types
    • #3687 Fix t.toExpression converting arrow functions to function expressions without block body. (@boopathi)
  • babel-traverse
    • #3629 Fix bug - undefined reference for export declaration. (@boopathi)
  • babel-helper-builder-binary-assignment-operator-visitor, babel-plugin-transform-es2015-classes
    • #3647 T7537: can not call super in constructor with conditional branch. (@d4rkr00t)

Documentation

  • Other

Internal

  • babel-traverse, babel-types

v6.14.0 (2016-08-23) TAKE ME TO FLAVOR TOWN

Lots of stuff in this release!

npm install babel-preset-es2017 --save-dev
// .babelrc
{ "presets": ["es2017"] }
  • #3625, #3673 A new preset called latest that transforms ES2015+ (currently ES2015, ES2016, ES2017). You can also pass options down to the es2015 preset.

We also will be working on getting a target/env (autoprefixer) preset soon.

npm install babel-preset-latest --save-dev
// .babelrc
{ "presets": ["latest"] }
// with options
{ "presets": [
  ["latest", {
    "es2015": {
      "modules": false 
    }
  }]
] }

spec for arrow functions uses .bind(this), instead of renaming, to make this available inside the transformed function. It also adds a runtime check to make sure they are not instantiated (since they transform into bound regular functions). spec for template literals wraps all expressions in String rather than simple string concatenation.

// .babelrc
{
  "presets": [
    ["es2015", { "spec": true }]
  ]
}
  • #3659 @kittens added an optional wrapPluginVisitorMethod callback to transform to allow for performance tracking/introspection of plugins. More docs will be added on the website soon.

  • #3658 sourcemaps will also now have a names field for identifiers to allow debuggers to do re-aliasing of mangled identifiers.

  • #3518 For spec compilancy, we now will throw on a file with multiple export default.

Notable Bug Fixes

  • #3527 Fix class inheritance in IE <=10 without loose mode.
  • #3644 Support the ignore config option in .babelrc.
  • #3655 Flow-only class props were not be stripped without transform-class-properties.

Guy Fieri

Commiters: 17

It's also a lot folk's first PR (or first code PR)!

New Feature

  • babel-preset-es2015
  • babel-preset-latest
  • babel-preset-es2017
  • babel-core, babel-traverse
    • #3659 Add wrapPluginVisitorMethod option to allow introspection and metrics tracking of plugins. (@kittens)
  • babel-cli, babel-core, babel-generator, babel-plugin-transform-regenerator, babel-template, babel-traverse
    • #3658 Generate names field for identifiers to get correct names mappings. (@kittens)
  • babel-generator, babel-types
    • #3570 Add support for the new declare module.exports of flow. (@danez)

Spec Compliancy

  • babel-plugin-transform-es2015-modules-amd, babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-es2015-modules-umd

Bug Fix

  • babel-core, babel-helper-replace-supers, babel-plugin-transform-class-properties, babel-plugin-transform-es2015-classes, babel-plugin-transform-es2015-function-name, babel-plugin-transform-es2015-object-super, babel-plugin-transform-es2015-parameters
    • #3527 Fix class inheritance in IE <=10 (T3041). (@danez)
  • babel-cli
  • babel-plugin-transform-es2015-modules-systemjs
  • babel-generator
    • #3663 Use arrow syntax for ObjectTypeProperty FunctionTypeAnnotations. (@zpao)
  • babel-register
    • #3608 Set sourceRoot in babel-register transform to fix paths in stacks. (@danez)
  • babel-plugin-transform-es2015-block-scoping
    • #3618 incorrect handling of returns nested in switch cases. (@ahl)
  • babel-traverse
  • babel-plugin-transform-flow-strip-types
    • #3655 Strip flow-only class props without needing transform-class-properties.. (@loganfsmyth)

Documentation

Internal

  • babel-preset-es2015, babel-preset-latest
  • babel-preset-es2015
  • Other
    • #3668 Ensure correct version of babel installed for preset options. (@danez)
    • #3645 Add es2015 loose mode back. (@hzoo)
    • #3639 Use es2015 loose mode after publish. (@hzoo)

v6.13.2 (2016-08-05)

Hi again, just fixing up logic from the backwards-compatibility fix which broke options in presets. Also added more tests and will update Babel to use the new preset options after this release.

Bug Fix

  • babel-core, babel-preset-es2015
    • #3638 [Bug Fix] option manager: val = val.buildPreset should be before the check if the preset supports options (@christophehurpeau)

v6.13.1 (2016-08-04)

We had a regression in our new babel-preset-es2015@6.13.0 that made it unexpectedly backward-incompatible. This release introduces a new alternative plugin-options approach that is uglier but supports backward-compatiblity. Ideally new plugins would use the new module.exports = function(babel, options){ } approach and simple skip supporting babel-core@<6.13.x.

Bug Fix

  • babel-core, babel-preset-es2015

v6.13.0 (2016-08-04)

Since the last release we've created https://github.com/babel/notes to track discussions on our slack and high level features/changes that could be added - definetely check it out if you're interested in Babel's development!

Some small but very important additions in this release:

Preset options (babel/notes)

Initially, presets were supposed to be one-off sets of plugins that didn't have any configuration. If you wanted to do something different you would make your own presets. There are > 600 presets on npm now. We want to give users more flexibility in certain cases: like when you want to pass the same option to multiple presets or to remove a default plugin.

loose and modules options for babel-preset-es2015 (#3331, #3627)

This has been rather annoying. Having to install babel-preset-es2015-loose-native-modules seems rather crazy when it could be an option.

With #3627, you can pass 2 options in:

  • loose - Enable "loose" transformations for any plugins in this preset that allow them (Disabled by default).
  • modules - Enable transformation of ES6 module syntax to another module type (Enabled by default to "commonjs"). Can be false to not transform modules, or one of ["amd", "umd", "systemjs", "commonjs"]
// for loose and native modules
{
  presets: [
    ["es2015", { "loose": true, "modules": false }]
  ]
}

Updates to babel-preset-stage-2

Coming Up

  • babel-preset-es2017, babel-preset-latest (still deciding the name), supporting codemods, and more!

New Feature

  • babel-core, babel-preset-es2015
    • #3627 es2015: transpile the preset, modify modules option to support "amd,umd,systemjs" as well, tests. (@hzoo)
    • #3331 Support passing options to presets.. (@loganfsmyth)
  • babel-preset-stage-1, babel-preset-stage-2

Bug Fix

  • babel-traverse

Polish

  • babel-plugin-transform-decorators
    • #3626 Show a more informative error message when using the decorator transf…. (@hzoo)

Internal

  • babel-types
    • #3628 Missing FlowType definition opts.deprecatedAlias. (@kpman)
  • babel-plugin-syntax-async-functions, babel-plugin-syntax-async-generators, babel-plugin-syntax-class-constructor-call, babel-plugin-syntax-class-properties, babel-plugin-syntax-decorators, babel-plugin-syntax-do-expressions, babel-plugin-syntax-exponentiation-operator, babel-plugin-syntax-export-extensions, babel-plugin-syntax-flow, babel-plugin-syntax-function-bind, babel-plugin-syntax-function-sent, babel-plugin-syntax-jsx, babel-plugin-syntax-object-rest-spread, babel-plugin-syntax-trailing-function-commas
    • #3604 Misc: remove deps from syntax plugins. (@hzoo)
  • babel-plugin-transform-inline-environment-variables, babel-plugin-transform-member-expression-literals, babel-plugin-transform-merge-sibling-variables, babel-plugin-transform-minify-booleans, babel-plugin-transform-node-env-inline, babel-plugin-transform-property-literals, babel-plugin-transform-remove-console, babel-plugin-transform-remove-debugger, babel-plugin-transform-simplify-comparison-operators, babel-plugin-transform-undefined-to-void
    • #3621 transfer minify plugins (will be in another repo). (@hzoo)
  • Other

Commiters: 7

v6.12.0 (2016-07-27)

  • Add a helpers: false option to transform-runtime to not bundle in babel helpers.
  • Add a exactGlobals option to modules-umd
  • Fix a regression with modules-systemjs
  • Fix a hoisting issue with react-constant-elements (@kittens is back!)

Bug Fix

  • babel-plugin-transform-react-constant-elements, babel-traverse
    • #3596 Fix React constant elements transform from hoisting elements to positions where their referenced bindings haven't been evaluated yet. (@kittens)
  • babel-plugin-transform-es2015-modules-systemjs

New Feature

  • babel-plugin-transform-runtime
    • #3603 Add helpers: false option to babel-plugin-transform-runtime. (@kittens)
  • babel-plugin-transform-es2015-modules-umd
    • #3534 Add exactGlobals option to transform-es2015-modules-umd plugin to enable more flexibility in specifying global names. (@rmacklin)

Commiters: 3

v6.11.6 (2016-07-26)

  • Reverts #3523 since it caused some issues with code coverage tools.
  • Update readme to explain Babel packages

Bug Fix

  • babel-register
    • #3599 Revert "Correct source map paths for babel-register.". (@hzoo)
  • babel-plugin-transform-es2015-modules-systemjs

Documentation

Commiters: 3

v6.11.5 (2016-07-23)

Thanks to Rob Eisenberg (EisenbergEffect), Keyan Zhang (keyanzhang), Rolf Timmermans (rolftimmermans), Thomas Grainger (graingert),

we have few fixes: fix babel-register file paths on error, infer class name for classes with class properties, fix export * to account for previously compiled modules.

Bug Fix

  • babel-plugin-transform-es2015-modules-amd, babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-es2015-modules-systemjs, babel-plugin-transform-es2015-modules-umd
  • babel-register
  • babel-plugin-transform-class-properties
    • #3589 Infer class name for classes that have static property initializer(s). (@keyanzhang)

v6.11.4 (2016-07-20)

In this release among other things are some more optimizations for babel-generator (#3584, #3580) as well as refactors.

@jamestalmage did some awesome clean for OptionsManager and some tests which may help future improvements to babel-register performance.

Bug Fix

  • babel-plugin-transform-remove-console, babel-plugin-transform-remove-debugger, babel-traverse
    • #3583 Add block if parent is non-block statement for remove-console/debugger. (@jhen0409)
  • babel-plugin-transform-regenerator
  • babel-cli
    • #3578 Support all variations of v8Flags in babel-node. (@danez)

Polish

  • babel-core
  • babel-generator, babel-plugin-transform-es2015-modules-commonjs
  • babel-plugin-transform-es2015-parameters
  • babel-generator

Commiters: 6

v6.11.3 (2016-07-13)

The main fix is @loganfsmyth's changes of some parts in babel-generator in #3565 to fix issues with exponential code generation times in certain cases.

Items: the size of the array being generated Time: The time in ms to generate the code Length: The number of characters in the output code

Items Old Time New Time Length
2 9 7 239
4 2 5 465
8 6 5 917
16 6 6 1840
32 15 11 3696
64 25 3 7408
128 93 13 14917
256 380 18 30149
512 1399 45 60613
1024 5301 63 121614
2048 20676 117 246542
  • Fix rest param optimization bug
  • Allow disabling "use strict" when using the cjs module transform.
  • Fix typo with es2016 preset

Bug Fix

  • babel-plugin-transform-es2015-parameters
  • babel-generator
  • babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-strict-mode
  • babel-preset-es2016

Polish

Commiters: 3

v6.11.2 (2016-06-28)

Bug Fix

v6.11.1 (2016-06-27)

Bug Fix

  • #3552 Remove jsx-self plugin from the react preset for now. (@hzoo)

Documentation

  • babel-types Update docs + scripts @ForbesLindesay

v6.11.0 (2016-06-26)

  • In this release, there's now an es2016 preset which includes the exponentiation operator (thanks for (@ysmood) for giving us the npm package).
  • The trailing-function-commas plugin has been moved from stage-2 preset to stage-3 preset.
  • babel-plugin-transform-react-jsx-self has been added to the react preset in development mode. There is a new dev warning being added in react and this plugin adds the __self={this} JSX attribute to all JSX elements.
  • babel-plugin-es2015-unicode-regex has it's regexpu-core dependency updated to 2.x.
  • Babel now uses lerna 2.x!

New Feature

  • babel-preset-es2016
  • babel-preset-stage-2, babel-preset-stage-3
  • babel-plugin-transform-react-jsx-self, babel-preset-react
    • #3540 Added jsx-self babel transform plugin. (@jimfb)

Spec Compliancy

  • babel-plugin-transform-es2015-unicode-regex

Bug Fix

  • babel-plugin-transform-react-jsx-self
  • babel-generator

Internal

  • Other
  • babel-code-frame

Commiters: 9

6.10.4 (2016-06-21)

Bug Fix

  • babel-traverse
    • Fix NodePath#evaluate to avoid a possible max-recursion-depth from an evaluation cycle (@kittens)

Internal

  • babel-core
    • Bump the from 2.x to 3.x for minimatch to avoid a deprecation warning (@theJian)

6.10.3 (2016-06-18)

Bug Fix

  • babel-plugin-transform-es2015-modules-commonjs

6.10.2 (2016-06-17)

@loganfsmyth made some awesome optimizations and better whitespace handling for babel-generator again (~10-15% performance improvement)!

Also a small fix for babel/babel-eslint#321

Bug Fix

  • babel-types
    • #3529 "name" should not be visited for TypeParameter. (@danez)

Internal

  • Other
    • #3528 cleanup transpiled files in make clean - Fixes #7434 [skip ci]. (@hzoo)
  • babel-generator
    • #3492 Refactor space insertion and remove some unneeded function options. (@loganfsmyth)

6.10.1 (2016-06-11)

Bug Fixes

  • #3525: Remove the nonfunctional -s shorthand for --skip-initial-build (@lxe)
  • #3526: Fix an issue with the switch handing from PR #3490 (@loganfsmyth)

6.10.0 (2016-06-11)

New Feature

  • babel-cli: Add a new option --skip-initial-build (#3489) (@lxe)

  • Do not compile files before watching

$ babel src -d dest --watch --skip-initial-build

Bug Fix

  • babel-plugin-transform-es2015-block-scoping: Create a new lexical environment inside switch statement blocks for identifier bindings (#3490, T7324) (@jayphelps)
let foo = false;

switch (true) {
  default:
    let foo = true;
}

alert(foo); // should be false
  • babel-types, babel-generator: Support changes in flow parsing in babylon

Add support for a TypeParameter node.

type A<T = string> = T;
class A<S = number, T: ?string = string> {};

Documentation

6.9.2 (2016-05-29)

Fixup missing dependency.

Bug Fix

  • babel-runtime: Fix an issue with getting Cannot find module 'regenerator-runtime' because it was set as a devDependency instead of a dependency.

6.9.1 (2016-05-29)

Just 2 fixes this release!

  • A class property fix (set this correctly when using async arrow function class properties without a super class).
  • A fix for react-constant-elements plugin to help optimize react more (the plugin wasn't applying to JSX with text).

Also, thanks to @mucsi96 for catching the extraneous code coverage comments we were leaving when publishing!

We are removing/deprecating babel-regenerator-runtime in favor of depending on the original regenerator-runtime since the differences are resolved. Thanks to (@benjamn) for the suggestion to maintain it (and for originally creating it!).

Bug Fix

  • babel-core
    • #3508 Assign _this to this when there is no Superclass in a Class when using class properties. Fixes T7364. (@ehjay)

The fix correctly set this: var _this; -> var _this = this;

// input
class MyClass {
  myAsyncMethod = async () => {
    console.log(this);
  }
}

// output
class MyClass {
  constructor() {
    var _this = this; // _this wasn't being set to `this`
    this.myAsyncMethod = babelHelpers.asyncToGenerator(function* () {
      console.log(_this);
    });
  }
}
  • babel-plugin-transform-react-constant-elements, babel-types

JSX with text in it was not being hoisted as other constant elements.

// input
var Foo = React.createClass({
  render() {
    return <div>Text</div>; // text wasn't considered constant
  }
});

// output
var _ref = <div>Text</div>;

var Foo = React.createClass({
  render() {
    return _ref;
  }
});

Internal

  • #3513 Make sure the env is production when publishing. (@hzoo)

  • babel-regenerator-runtime

  • babel-core
    • #3446 Use more ideal mocha hooks in babel-core/test/api. (@jmm)
  • babel-polyfill, babel-regenerator-runtime, babel-runtime
    • #3494 Use regenerator-runtime from npm; removed babel-regenerator-runtime fork since there aren't differences anymore. (@benjamn)

6.9.0 (2016-05-17)

  • Update core-js from 2.1.0 to 2.4.0. Check the releases for more info.
  • Add a systemGlobal option in the systemjs transform.
["transform-es2015-modules-systemjs", {
  // outputs scoped_system.register(...)
  "systemGlobal": "scoped_system" // defaults to System.register
}]
  • Bug fixes for class-properties and react-jsx-source plugins.

New Feature

  • babel-types
    • #3470 Add validation of type fields for parameter decorators. (@shuhei)
  • babel-plugin-transform-runtime, babel-polyfill, babel-register, babel-runtime
  • babel-plugin-transform-es2015-modules-systemjs
    • #3482 Add systemGlobal option to allow changing the System in System.register to be systemGlobal. Also move use strict wrapping. (@guybedford)

Bug Fix

  • babel-plugin-transform-react-jsx-source
  • babel-plugin-transform-class-properties
    • #3486 Add path.ensureBlock for ArrowFunctionExpression in a ClassExpression when there is a ClassProperty. (@jhen0409)
  • babel-traverse
  • babel-plugin-transform-es2015-parameters

Documentation

Internal

Upgrade to lodash 4.

  • babel-traverse
    • #3501 Remove repeating dependency from babel-traverse. (@dlwalsh)
  • babel-helper-fixtures
    • #3502 Replace trim-right with _.trimEnd in babel-helper-fixtures. (@dlwalsh)
  • babel-generator
    • #3500 Remove micro dependencies in favour of lodash functions for babel-generator. (@dlwalsh)
  • babel-cli, babel-core, babel-generator, babel-helper-builder-react-jsx, babel-helper-define-map, babel-helper-fixtures, babel-helper-regex, babel-helper-transform-fixture-test-runner, babel-plugin-transform-es2015-block-scoping, babel-plugin-transform-es2015-function-name, babel-plugin-transform-proto-to-assign, babel-preset-es2015, babel-register, babel-runtime, babel-template, babel-traverse, babel-types

Thanks to amasad, dlwalsh, forivall, frantic, graingert, guybedford, jayphelps, jhen0409, loganfsmyth, shuhei, zloirock!

6.8.0 (2016-05-02)

Babel is now compiled with Babel 6!

Why this is relevant

TLDR: This fixes the npm deduping issues regarding babel-runtime 5 and 6.

  • Because all Babel packages were compiled with Babel 5 and using babel-runtime@5, npm can't dedupe any of them if a consumer of Babel also added a dependency on babel-runtime@6.

Example:

└─┬ babel-plugin-transform-exponentiation-operator@6.5.0
  β”œβ”€β”¬ babel-helper-builder-binary-assignment-operator-visitor@6.6.5
  β”‚ β”œβ”€β”¬ babel-helper-explode-assignable-expression@6.6.5
  β”‚ β”‚ └── babel-runtime@5.8.38
  β”‚ └── babel-runtime@5.8.38
  β”œβ”€β”¬ babel-plugin-syntax-exponentiation-operator@6.5.0
  β”‚ └── babel-runtime@5.8.38
  └── babel-runtime@5.8.38

Now it should be more like:

└─┬ babel-runtime@6.8.0
└─┬ babel-plugin-transform-exponentiation-operator@6.8.0
  β”œβ”€β”¬ babel-helper-builder-binary-assignment-operator-visitor@6.8.0
  β”‚ β”œβ”€β”¬ babel-helper-explode-assignable-expression@6.8.0
  β”œβ”€β”¬ babel-plugin-syntax-exponentiation-operator@6.8.0

Related issues: T7252, T7275, T6689, sindresorhus/ava#660, vuejs/vue-loader#96, etc.

Internal

Misc

6.7.7 (2016-04-20)

Bug Fix

  • babel-code-frame

    • #3464 - Handle tab-indented code when marking errors (@lydell)
  • babel-core

  • babel-generator

Misc

  • babel-plugin-transform-es2015-modules-commonjs

  • babel-generator, babel-types

6.7.6 (2016-04-08)

6.7.5 (2016-04-07)

Bug Fix

  • babel-traverse

  • babel-core/babel-cli

    • #3448: Make sure input to path.{dir,base}name is a string. (@addaleax)
    • #3451: Handle input sourcemaps with mappings to nothing to better support sourcemaps from other tools in a pipeline. (@loganfsmyth)
  • babel-helper-builder-react-jsx

    • #3444: Preserve whitespace in JSXExpressionContainer StringLiteral children. (@drd)
  • babel-generator

    • #3421: Wrap parens around default exports starting with function/class. (@loganfsmyth)

Misc

  • babel-plugin-transform-runtime

  • babel-traverse

6.7.4 (2016-03-22)

Bug Fix

  • babel-traverse

  • babel-runtime

  • babel-plugin-transform-react-jsx

    • #3430: Stop the JSX transform from using an AST node in two places. (@amasad)

Misc

Internal

  • #3400: Fix an issue that could cause a local clone of Babel to error out if the github repo was in a location with a parent .babelrc file. (@callumlocke)
  • #3431: Fix an issue that was causing the local-development watcher to occasionally rebuild with the incorrect file content. (@loganfsmyth)
  • #3436: Update our linting utility version. (@hzoo)
  • #3437: Remove an unused dependency. (@hzoo)
  • babel-core

6.7.3 (2016-03-22)

  • babel-code-frame
    • Dropped problematic line-numbers dependency which was broken due to the unexpected unpublishing of its dependency left-pad@0.0.3.

6.7.3 (2016-03-10)

Bug Fix

  • babel-traverse
    • Fix a bug which caused the new Flow binding warning to show more often than expected (@amasad).

6.7.2 (2016-03-10)

Flow fix, mention babylon move

Bug Fix

  • babel-traverse
    • #3414: Warn on Flow-based bindings and don't count as a const violation. (@amasad)

We are treating static type information as part of the runtime scope information. So a Flow type declaration was being considered a binding on the scope. This was specifically problematic when we thinking that we're overwriting a binding:

The following code:

declare class foo {}
const foo = 1;

Will result in the error: "foo" is read-only

Since removing support for flow-based bindings would be a breaking change, in this release I'm adding a warning whenever someone tries to use Flow types as bindings.

Internal

  • babel-code-frame, babel-generator, babel-messages, babel-plugin-undeclared-variables-check, babel-polyfill, babel-register, babel-traverse, babel-types
  • babylon

6.7.1 (2016-03-09)

Bug Fix

  • babel-plugin-transform-es2015-block-scoping
    • #3411 Fixes T7197: Move bindings without losing any information.

The following code:

let foo = () => {
  foo = () => { };
};

foo();

Was generating:

var foo = function foo() {
  foo = function foo() {};
};

foo();

Notice how the function name foo was is shadowing the upper scope variable. This was fixed and the generated code now is:

var _foo = function foo() {
  _foo = function foo() {};
};

_foo();

6.7.0 (2016-03-08)

Notable changes:

  • Various async function fixes (const read-only error, wrong this, etc)
  • Proper sourcemaps for import/export statements
  • Moved internal Babel cache out of the AST

New Feature

  • babel-traverse

Move cache into a clearable WeakMap, adds traverse.clearCache and traverse.copyCache. This doubles as a bug fix because previously reusable AST Nodes would carry their cache with them even if they're used across multiple files and transform passes.

  • babel-generator, babel-plugin-transform-flow-comments, babel-plugin-transform-flow-strip-types, babylon
// examples
class C<+T,-U> {}
function f<+T,-U>() {}
type T<+T,-U> = {}

This syntax allows you to specify whether a type variable can appear in a covariant or contravariant position, and is super useful for, say, Promise. @samwgoldman can tell you more πŸ˜„.

  • babel-generator, babylon
    • #3323 Source-map support for multiple input source files. (@divmain)

More docs on this in the babel-generator README

Bug Fix

  • babel-traverse

Make sure all existing let/const bindings are removed and replaced with vars after the block-scoping plugin is run.

This fixes: SyntaxError: src/foo.js: "baz" is read-only (This is an error on an internal node. Probably an internal error. Location has been estimated.)

async function foo() {
  async function bar() {
    const baz = {}; // was creating a read-only error
  }
}
  • babel-core, babel-traverse, babel-helper-remap-async-to-generator, babel-helper-replace-supers, babel-plugin-transform-async-to-generator, babel-plugin-transform-async-to-module-method

Should fix the majority of issues dealing with async functions and use of parameters, this, and arguments.

// fixes
class Test {
  static async method2() {
    setTimeout(async (arg) => {
      console.log(this); // was showing undefined with arg
    });
  }

  async method2() {
    setTimeout(async (arg) => {
      console.log(this); // was showing undefined with arg
    });
  }
}
  • babel-helper-remap-async-to-generator, babel-plugin-transform-async-to-generator, babel-plugin-transform-async-to-module-method

The problem is that the name bar of FunctionExpression is only visible inside that function, not in foo or ref.

// input
var foo = async function bar() {
  console.log(bar);
};


// before
var foo = function () {
  var ref = babelHelpers.asyncToGenerator(function* () {
    console.log(bar);
  });

  return function bar() {
    return ref.apply(this, arguments);
  };
}();

// now
var foo = function () {
  var ref = babelHelpers.asyncToGenerator(function* () {
    console.log(bar);
  });

  function bar() {
    return ref.apply(this, arguments);
  }

  return bar
}();
  • babel-plugin-transform-es2015-parameters

Many fixes to rest params: function asdf(...rest) { ... }

  • babel-template

  • babel-plugin-transform-es2015-modules-commonjs

    • #3409 Fix source map generation for import and export statement.

Internal

  • babel-plugin-transform-es2015-modules-commonjs
    • #3383 Test for regression with exporting an arrow function with a default param. (@hzoo)

Commiters: 6

amasad, divmain, hzoo, jmm, keijokapp, loganfsmyth, samwgoldman

6.6.5 (2016-03-04)

And.. some more bug fixes!

Bug Fix

  • babel-plugin-transform-es2015-computed-properties
// lead to `ReferenceError: b is not defined` at runtime
var obj = {
  ["a"]: 5,
  set b(x) { console.log('set b', x); }
};

obj.b = 55;
  • babel-plugin-transform-object-rest-spread, babel-types
import props from 'props';
console.log(props);

(function(){
  const { ...props } = this.props;

  console.log(props); // props was referencing the imported props rather than in object spread
})();
  • babel-plugin-transform-es2015-block-scoping
    • #3389 Update scope binding info after transforming block-scoped bindings. (@amasad)

Scope binding info wasn't updated after converting const/let/block bindings to var which could lead to errors with other transforms.

Internal

  • #3398 Revert "Remove flow". (@amasad)
  • #3397 Make sure lib is clean before publishing. (@hzoo)
  • babel-core, babel-plugin-transform-es2015-block-scoping, babel-plugin-transform-es2015-classes
    • #3399 use flow instead of flow-comments. (@hzoo)
  • babel-plugin-transform-es2015-modules-amd, babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-es2015-modules-umd

Commiters: 5

AgentME, amasad, benjamn, hzoo, loganfsmyth

6.6.4 (2016-03-02)

Some more fixes!

Bug Fix

  • babel-plugin-transform-es2015-duplicate-keys
    • #3388 Partial T7173 Fix: Prevent accessors being seen as duplicates of each other. (@AgentME)
// sample code that was erroring
const obj = {
  set a (a) {
    values.a = a;
  },
  get a () {
    return values.a;
  }
};
  • babel-core
    • #3350 Make Babel actually resolve plugins relative to where they were specified (via .babelrc).. (@skevy)
// .babelrc
{
  "plugins": ["./myPluginDir/somePlugin.js"]
}

Babel will now resolve the plugin above relative to the directory that contains the .babelrc file rather than the process.cwd().

Internal

Since users were getting error reports since Babel's codebase wasn't typechecking correctly. (Ref T7114) - Will be adding it back into the codebase itself soon.

6.6.3 (2016-03-01)

Bug Fix

  • babel-plugin-transform-es2015-modules-commonjs, babel-traverse
    • #3387 Fix regression with T7165 - let is not being transpiled when using export all (block-scoping transform wasn't run) (@loganfsmyth)
// example code
`export * from './a'`

6.6.2 (2016-03-01)

Bug Fix

  • babel-plugin-transform-es2015-modules-commonjs, babel-traverse
// example code
export var bar = (gen, ctx = null) => {}

6.6.1 (2016-02-29)

Bug Fix

  • babel-runtime, babel-polyfill: Fix publishing issue (wasn't updated from before).

6.6.0 (2016-02-29) "core-js 2, better error feedback"

Whoo a 🐸 leap day release!

exports.default fix

We finally fixed both T2817, T6863 where using both transform-es3-member-expression-literals and transform-es2015-modules-commonjs!

exports.default = {};
// was not to transformed to
exports["default"] = {};

You should be able to remove es3ify (a useful workaround for this issue). Thanks everyone for your patience, and much thanks to @loganfsmyth for the fix!

More helpful error messages

  • If you are using a .babelrc with babel 5 options that were removed (there is a specific message for each one)
# before
ReferenceError: [BABEL] unknown: Unknown option: base.stage
# now
ReferenceError: [BABEL] unknown: Using removed Babel 5 option: base.stage
- Check out the corresponding stage-x presets http://babeljs.io/docs/plugins/#presets
# another example
ReferenceError: [BABEL] unknown: Using removed Babel 5 option: base.externalHelpers
- Use the `external-helpers` plugin instead. Check out http://babeljs.io/docs/plugins/external-helpers/
  • If you are trying to use a babel 5 plugin
# before
babel Plugin is not a function
# now
The object-assign Babel 5 plugin is being run with Babel 6.

core-js

  • core-js was updated to ^2.1.0.

New Feature

New plugin babel-plugin-transform-es2015-duplicate-keys
  • babel-plugin-transform-es2015-duplicate-keys, babel-preset-es2015

babel-plugin-transform-es2015-duplicate-keys is a new plugin that is included in the es2015 preset. It was added since ES5 doesn't allow duplicate properties (it is valid in ES2015 strict mode however).

It will compile objects with duplicate keys to computed properties, which can be compiled with the transform-es2015-computed-properties plugin.

Example:

// .babelrc
{ "plugins": ["transform-es2015-duplicate-keys"] }
// Input
var x = { a: 5, "a": 6 };
// Output
var x = { a: 5, ["a"]: 6 };
New globals option for transform-es2015-modules-umd
// Adds a new plugin option to let you override the names of globals
// .babelrc
{
  "plugins": [
    ["transform-es2015-modules-umd", {
      "globals": {
        "es6-promise": "Promise"
      }
    }]
  ]
}

Bug Fix

  • babel-plugin-transform-es2015-modules-commonjs, babel-traverse
    • #3368 Fix the module plugin to properly requeue so the ES3 transforms can work. (@loganfsmyth)
  • babylon
  • babel-generator
    • #3358 Fix generator with empty token list and force a newline for line comments in concise mode. (@gzzhanghao)
  • babel-plugin-transform-es2015-parameters
    • #3249 Assignment to rest param element triggers error T6932. (@jmm)
// .babelrc
{ plugins: ["transform-es2015-parameters"] }

// Fixes an internal error with the code:
function x (...items) {
  items[0] = 0;
}
  • babel-helper-remap-async-to-generator, babel-plugin-transform-es2015-parameters
// .babelrc
{
  "plugins": ["external-helpers", "transform-es2015-parameters", "transform-async-to-generator"]
}

// Fixes an issue with using incorrect `arguments`
var x = async (...rest) => {
  if (noNeedToWork) return 0;
  return rest;
};
  • babel-plugin-transform-regenerator, babel-traverse
    • #3359 Queue regeneratorRuntime so it is transformed before Program#exit. (@loganfsmyth)

Fixes the _regeneratorRuntime is not defined error when using transform-runtime/transform-regenerator (this happened when using polyfillable code in core-js.

  • babylon
  • babel-plugin-transform-es2015-block-scoping
    • #3346 Rename scope bindings during block scope transform. (@schmod)
  • babel-generator
    • #3380 Fix: Add parens for unary arrow function. (@hzoo)
// input
void (() => {});
// correct output
void (() => {});
// wrong
void () => {};
  • babel-generator
    • #3379 Fix: invalid codegen for non decimal numeric literals in MemberExpression. (@hzoo)
// input
(0xFFFF).toString()
// correct output
0xFFFF.toString()
// wrong
0xFFFF..toString()

Documentation

  • babel-plugin-transform-regenerator
    • #3370 Adds repository field to babel-plugin-transform-regenerator. (@siroky)
  • babel-plugin-transform-object-set-prototype-of-to-assign
  • babel-cli

Internal

  • #3378 Remove Flow annotations and pragmas. (@samwgoldman)
  • #3361 Switch to kcheck*, fix some lint rules. (@kittens)
  • babel-plugin-transform-runtime, babel-polyfill, babel-register, babel-runtime

Polish

  • babel-core, babel-traverse
  • babel-core
    • #3362 Show a better error when trying to use a babel 5 plugin. (@hzoo)
  • babel-core
    • #3377 Give specific error messages for babel 5 options that were removed in babel 6. (@hzoo)

We have 15 committers this release!

Thanks to: AgentME, clayreimann, erikdesjardins, forivall, gzzhanghao, hzoo, jmm, jridgewell, kittens, loganfsmyth, samwgoldman, schmod, siroky, tiemevanveen, zloirock

6.5.2 (2016-02-12) "Who needs semicolons anyway” Β―\(ツ)/Β―

Changes to note:

  • Reverting the class properties semicolon parser error.
  • Fix regression with plugin ordering with babel-register.

Spec Compliancy

  • babel-plugin-transform-class-properties, babylon

Bug Fix

  • babel-core, babel-register
  • babel-plugin-transform-es2015-spread

    // input
    super.method(...args);
    // wrong output
    super.method.apply(super, babelHelpers.toConsumableArray(args));
    // new fixed output
    super.method.apply(this, babelHelpers.toConsumableArray(args));
  • babel-plugin-transform-function-bind, babel-types

Documentation

  • babel-register
  • babel-plugin-transform-async-to-module-method, babel-plugin-transform-es2015-arrow-functions, babel-plugin-transform-es2015-classes, babel-plugin-transform-es2015-computed-properties, babel-plugin-transform-es2015-for-of, babel-plugin-transform-es2015-modules-commonjs, babel-plugin-transform-es2015-spread, babel-plugin-transform-es2015-template-literals, babel-plugin-transform-react-jsx, babel-plugin-transform-regenerator, babel-plugin-transform-runtime, babel-plugin-transform-strict-mode
    • #3345 Update all plugin readmes with options. (@hzoo)
  • #3352 Fix a typo. (@pra85)

Internal

  • babel
  • babylon
    • #3351 Add class properties test with a generator method that results in a p…. (@hzoo)
  • #3344 Travis: Remove 0.10, since it's covered by Circle. (@hzoo)
  • #3343 Travis CI: Switch from deprecated stable NodeJS to latest 4.x.x & 5.x.x. (@ntwb)
  • #3341 bin-version-check is unnecessary now. (@chicoxyzzy)
  • #3339 Know how to write good shell scripts. (@hzoo)

6.5.1 (2016-02-08) Daddy does a release.

  • Bug Fix
    • bc2f84f3712a4bcf5619161955c5597298db5c5b Fix options being ignored in babel-register.
    • #3329 Fix ExportSpecifier node validator validating imported instead of exported.
  • Polish
    • #3333 Improve the error messaging for using the wrong CLI script.

6.5.0 (2016-02-07)

Happy Superbowl Sunday! There's many contributors (17 + core) this release!

A traversal per preset (Experimental)

This is an experimental feature that will most likely change. Depending on usage/feedback, we will switch the way this is used to instead define a explicit preset-level config flag (rather than the global one below). This will give more control over how you want to use this option.

@DmitrySoshnikov added a new option you can put in your .babelrc!

{
  passPerPreset: true,
  presets: [
    {
      plugins: ['plugin-1']
    },
    'preset-2',
    {
      plugins: ['plugin-2']
    }
  ]
}
// this will create 3 traversals

passPerPreset: true will modify how babel traverses through plugins. Instead of a single traversal in which all plugins/presets are merged together, each preset will get their own traversal.

This allows users to have a specific order to how presets/plugins are applied and can help avoid potential collisions between plugins (and probably some known issues).


More Speeeeeeed

@gzzhanghao made some awesome changes to improve our code generator's performance (babel-generator). The original issue is here.

Based on his test (on parsing jquery.js), performance improved ~3x.

===== origin/master (ms) =====
babylon 265
babel generator 2238 <-- old
acorn 107
escodegen 355
esprima 95
escodegen 322
===== Optimized (ms) =====
babylon 296
babel generator 662 <-- new
acorn 113
escodegen 355
esprima 106
escodegen 317

A big change had to do with keeping this.last as an instance variable in the buffer instead of this.buf[this.buf.length -1].

You can read more about his changes here. Hoping to see more PR's like this!

We will try to setup some perf tests soon to track these stats for the future (or you can help!).

New Feature

  • babel-core
  • babel-core
    • #3281 passPerPreset option in .babelrc: if true, babel will create a new traversal for each preset. (@DmitrySoshnikov)
  • babel-helper-transform-fixture-test-runner, babel-plugin-transform-react-jsx-source
    • #3285 Hoist the current file name (an absolute path) for transform-react-jsx-source . (@frantic)

This plugin (useful for tooling) will turn

// this/file.js
<sometag />

into

var _jsxFileName = "this/file.js"; // the output will be an absolute path
var x = <sometag __source={{
  fileName: _jsxFileName,
  lineNumber: 1
}} />;
  • babel-template
  • babel-core
    • #3313 Add babel.analyze - an api sugar for getting back metadata from babel. (@kittens)
// analyse not analyze :D
// usage
babel.analyse("foobar;", {}, {
  Program: function (path) {
    path.mark("category", "foobar");
  }
}).marked[0].message // outputs "foobar"
  • babylon
    • #3319 Add support for leading pipes in Flow type alias RHS syntax (@jeffmo)
// allows for either `|` or `&`
type union =
 | {type: "A"}
 | {type: "B"}
;

This was added in flow in 7fb56ee9d8.

Bug Fix

Code samples below each bullet

  • babel-helper-define-map, babel-helper-function-name, babel-plugin-transform-es2015-classes
    • #3298 Set NOT_LOCAL_BINDING symbol on all inferred function names. (issue T7010, regression of #3274) (@amasad)
// When the same name as a method in a class is used

class Foo {
  constructor(val) {
    this._val = val;
  }
  foo2() {
    return foo2(this._val); // was erroring since foo2 is used
  }
}
  • babel-helper-remap-async-to-generator, babel-plugin-transform-async-to-generator
// nested arrow functions
class A {
  async method() {
    () => {
      () => this; // `this` in nested arrow function was incorrect
    }
  }
}
  • babel-template

    • #3314 Only strip node info if no node.loc. Fixes an issue with sourcemap generation for SystemJS with babel-template. (Issue T6903) (@guybedford)
  • babel-traverse

    • #3300 Fix an issue with transpiling generator functions with default arguments. (Issue T2776) (@gzzhanghao)
// a generator with a default argument
export class Test {
    *memberGenerator(arg = 0) {
        console.log(arg);
    }
    start() {
        this.memberGenerator(1).next();
    }
}
  • babel-generator
    • #3311 Consider arrow functions when parenthesizing object expressions. (Issue T7047) (@amasad)
var fn = () => ({}).key;
  • babel-helper-remap-async-to-generator, babel-plugin-transform-es2015-modules-commonjs
foo();

async function foo() {} // this should be hoisted above foo();
  • babel-generator
    • #3324 Parenthesize the in in a for-loop init, even in the case when it is nested. (@zjmiller)
// nested for loop
for (function(){for(;;);} && (a in b);;);
const X = (
  props: SomeType,
): ReturnType => (
  3
);

Documentation

  • #3321 Docs: add information on writing tests in babylon. (@hzoo)
  • #3308 Update compiler-environment-support.md. (@sappharx)
  • #3293 ast/spec: update Decorator property. (@hzoo)
  • #3295 ast/spec: add BindExpression. (@hzoo)
  • #3287 Correct use of possessive case. (@nettofarah)
  • #3301 ast/spec: add Literal and Pattern interfaces, update Identifier interface. (@jmm)

Internal

  • #3317 make publish: add make build in case it wasn't run. (@hzoo)
  • babel-generator
  • babel-core, babel-generator, babel-traverse, babel-types,babylon
    • #3186 Add more flow types, update flow, eslint, babel-eslint, only run flow on node 5. (@hzoo)
  • babel-core
  • babel-plugin-transform-async-to-generator
  • babel-generator
    • #3299 Add a test to ensure that we do not break mutli-byte handling. (@robcolburn)
  • babel-cli
    • #3307 Make the chokidar dependency optional. (@josh)
  • babel-types
    • #3294 WithStatements can have statements as bodies. (@amasad)
  • babel-types

Polish

6.4.6 (2016-01-20)

  • Bug Fix
    • babel-helper-remap-async-to-generator: #3288 Async arrow functions should compile to regular functions because they reference arguments.

6.4.5 (2016-01-19)

  • Bug Fix

    • babel-plugin-transform-es2015-modules-commonjs: #3118 Fix bad import hoisting interaction (copy _blockHoist values) regarding import statements. (T6738). Thanks @benjamn for your patience for this one!

      • This fixes:
      var _templateObject = (0, _taggedTemplateLiteral3.default)(["foo"], ["foo"]); // this should come after _taggedTemplateLiteral 2 and 3
      var _taggedTemplateLiteral2 = require("babel-runtime/helpers/taggedTemplateLiteral");
      var _taggedTemplateLiteral3 = _interopRequireDefault(_taggedTemplateLiteral2);
      
      tag(_templateObject);
    • babel-types, babel-plugin-transform-es2015-modules-commonjs, babel-generator: #3183 Fix various source map issues. (T6851). Thanks for your work @kpdecker! Committed as de51bf5
    • babel-helper-remap-async-to-generator: #3257 Fix issue with using this inside an arrow function (T2765). Thanks @horpto!
      • This fixes:
      class A {
        async method() {
          () => this; // this `this` wasn't being transpiled correctly
        }
      }
    • babylon: #3272 Dedupe parser opts from passsed in multiple times. (T3084). Thanks @AgentME!
      • This fixes a specific issue with the react preset since it includes syntax-flow and transform-flow-strip-types which caused an issue with the flow types not to be stripped and the general case of other people are including the flow syntax option in their own plugins.
    • babel-helper-define-map, babel-traverse, babel-plugin-transform-es2015-classes: #3274 Prevent method names in classes from being locally bound to the transformed function body. (T6712). Thanks @willheslam for helping to debug and coming up with alternative solutions for this issue!
      • This fixes:
        SyntaxError: index.js: "foo" is read-only (This is an error on an internal node. Probably an internal error. Location has been estimated.)
        1 | class Component {
        2 |   foo() {
        3 |     const foo = obj;
        4 |   }
        5 | }
        6 |
    • babel-helpers: #3276 Add missing return statements to asyncToGenerator helper.
    • babel-plugin-transform-es2015-modules-commonjs: #3282 Fixes an issue with using default as a specifier in an export.
      • This fixes an issue with:
      export {default as foo} from "foo";
  • Documentation

    • babel-traverse: #3269 Document visitors.explode. Thanks @forivall!
  • Internal

    • babel-plugin-transform-es2015-parameters: #3263 Test coverage.
    • babel-core: #3268 Add a test for (T2892).
    • #3275 Temporarily change flow types to fix lint.
    • #3277 Fixup Makefile .bin references. Thanks @charliesome!
    • #3278 Use local bin references instead of implied global in Makefile.
    • babylon: #3284 Add some more flow types. Thanks @bmeck!
  • Polish

    • babel-plugin-transform-es2015-parameters: #3264 Simplify code, add comments.

6.4.4 (2016-01-13)

  • babel-plugin-transform-regenerator: Publishing issue (T2892).

6.4.3 (2016-01-13)

  • Bug Fix

    • babel-plugin-transform-es2015-typeof-symbol: #3250 The typeof transform should always use the global Symbol.
    • babel-plugin-transform-es2015-modules-amd: #3252 Stop leaking directives
    • babel-pluginn-transform-es2015-unicode-regex: #3259 Use only regexpu-core instead of all of regexpu
    • babel-generator: Fix minified labeledStatement printing
    • babel-plugin-transform-regenerator: #3162 Make sure babel helper picks up regeneratorRuntime
  • Polish

    • babel-types: #3261 Add ArrayExpression.elements.default
    • babel-register: #3232 Make sure the cache file's directory exists
  • Documentation

    • babel-generator-options: #3251 Document babel-generator options

6.4.2 (2016-01-06)

  • Bug Fix
    • babylon: #3244 fix error location for class properties with a missing semicolon (Ref #3225).
    • babel-plugin-transform-es2015-parameters: #3246 Support expressions in rest arg access for arguments.length optimization.
    • babel-generator: #3247 Parenthesize await/yield expression in BinaryExpression (Ref #3229).

6.4.1 (2016-01-06)

  • Bug Fix
    • babel-types: #3245 Temporarily revert adding the Binary alias #3217 and tests.

6.4.0 (2016-01-06)

Thanks to @samwgoldman for all the new flow support!

  • New Feature

    • babylon, babel-types, babel-generator: #3202 Add support for this flow type.
    • babylon, babel-types, babel-generator: #3236 Add support for export interface flow syntax.
    • babylon, babel-types, babel-generator, babel-plugin-transform-flow-strip-types, babel-plugin-transform-flow-comments: #3230 Add support for declare type and declare interface flow syntax.
    • babylon, babel-types, babel-generator, babel-plugin-transform-flow-strip-types, babel-plugin-transform-flow-comments: #3203 Add support for flow mixins.
    • babel-cli: #3221: Handle --nolazy flag.
    • babel-plugin-transform-es2015-modules-systemjs: #3166 Add __moduleName support to System.register. Thanks @guybedford!
  • Bug Fix

    • babel-plugin-transform-es2015-parameters: #3214 Bugfix for arguments.length optimization having the wrong length. Thanks @fabiomcosta!
    • babylon: #3220 Don't parse parenthesized string as a Directive.
    • babel-helpers: #3218 Defer to the built-in typeof if support for Symbols exists. Thanks @jdalton!
    • babel-generator: #3213 Fix various parentheses bugs.
    • babel-plugin-transform-react-display-name: #3216 More relaxed displayName inference.
    • babel-helper-function-name: #3215 Set function names from AssignmentExpression. Thanks @spicyj!
    • babel-generator: #3210 Use a print stack to determine in parenthesis needs to be added.
    • babel-plugin-transform-runtime: #3235 Ensure opts.polyfill = false behaves correctly for all visitors. Thanks @guybedford!
    • babel-plugin-transform-runtime: Ensure regenerator option doesn't cancel out core-js polyfill.
    • babel-generator: #3229 Check for parentheses for AwaitExpressions and fix over-parentheses in YieldExpressions.
  • Breaking Change (Accidental)

    • babylon: #3225 throw parse error if class properties do not have a semicolon.
    • babel-types: #3195 Allow JSXText node in JSXElement children property and remove StringLiteral.
  • Documentation

    • babel-generator: #3240 Fix small in babel-generator README sample code. Thanks @athaeryn!
  • Internal

    • babel-plugin-external-helpers: #3205 Renamed from babel-plugin-external-helpers-2 due to someone taking the npm name beforehand.
    • #3233 Update LICENSE end date to 2016. Thanks @maclover7!
    • babylon: #3204 Prevent users from patching by building it.
    • babel-types: #3217 Add Binary alias to AssignmentExpression.

6.3.26

  • Bug Fix

    • babel-plugin-transform-es2015-parameters: #3191 Fix the order of arguments initialization (fixes T6809)
    • babel-traverse: #3198 In evaluate(), it should not mistake lack of confidence for falsy
  • Spec Compliancy

    • babylon, babel-generator, babel-plugin-transform-regenerator: #3190: Remove await * from babylon and raise an error for that syntax since it was removed from the proposal and was causing an issue at runtime but not at compile time (fixes T6688).
  • Internal

    • Fix gulp build path to work on windows (fixes T6855).
    • babel: #3193 Point users to the cli docs
    • babel-core: #3196 Add a test for checking plugins/presets are resolved relative to filename

6.3.25

  • Bug Fix

    • babylon: #3187 Multiple "use strict" in function causes outer scope to be parsed as strict
    • babel-generator: #3188 Correctly set format.quotes to opts.quotes
    • babel-generator: #3189 JSX attributes should use double qoutes
    • babel-traverse: #3192 Fixed static evaluation bug
  • Internal

    • babel-plugin-transform-es2015-parameters: #3165 Optimize arguments access

6.3.24

  • Bug Fix
    • #3184 Fixed overly permissive type inference.

6.3.22-6.3.23

Skipped 6.3.22.

  • Internal
    • Renamed the Flow Comments plugin from babel-plugin-flow-comments to babel-plugin-transform-flow-comments for naming consistency.

6.3.21

  • Bug Fix

    • babel-generator: #3173 Fix unhandled new-precedence edge cases regarding parentheses (fixes T6829).
    • babel-generator: #3180 Handle nested IfStatement with an `alternate.
    • babel-generator: #3182 Parenthesize ArrowFunctionExpression when part of a LogicalExpression or BinaryExpression (fixes T6836).
    • babel-traverse: #3171 Fix infinite recursion bug with introspection method.
    • transform-es2015-function-name: #3176 Stop transforming ObjectMethod (MethodDefinition) to a FunctionExpression since the transform-es2015-shorthand-properties plugin already does it.
    • transform-es2015-parameters: #3143 Optimizations for RestElement such as using arguments.length (fixes T6774).
  • Documentation

    • babel-core: #3177 Clarify description of comments file config.
  • Internal

    • *: #3179 Update flow to 0.20.0 and add @noflow until types are added in.
    • babel-generator: #3178 Fix type annotation for shouldPrintComment.

6.3.20

  • Bug Fix
    • babel-generator: #3170 Fix invalid code generation for numeric MemberExpression (5.toString() -> 5..toString()).
    • babel-types: #3172 Add Expression alias to BindExpression.

6.3.19

  • New Feature

    • babel-plugin-flow-comments: #3157 Move babel-plugin-flow-comments to the babel repo and update for babel 6.
  • Bug Fix

    • babel-runtime: #3142 Add a custom transform for babel-runtime builds to avoid circular dependencies (Fixes the babel-runtime/helpers/typeof issue).
    • babel-traverse: #3161 Only rename the *outer function bindings on name conflict.
    • babel-generator: #3167 Use the left most node from the right to check if we need spaces in BinaryExpressions.

6.3.18

  • Bug Fix

    • babylon: #3107 Fix incorrect directive parsing
    • babel-generator: #3158 Parenthesize object expression when it may end up at the start of an expression
    • babel-plugin-transform-regenerator: #3160 Fix typo
  • Polish

    • babel-types: #2933 Generate documentation for babel-types.
    • babel-plugin-transform-es2015-parameter: #2833 Optimize arguments usage.
    • babel-messages: #3123 clarify traverseNeedsParent message.

6.3.17

  • Bug Fix

    • babel-types: #3153 DoWhileStatement should take node type Statement as body.
  • New Feature

    • babel-generator: #3152 Add a new minified format option to do possibly dangerous byte saving.
  • Internal

    • babel-traverse: #3151 Support ObjectProperty in Scope.isPure
  • Polish

    • babel-cli: #3150 Do not prefer global when installing babel-cli

6.3.16

  • Bug Fix

    • babel-traverse:
      • #3137 Set the correct parent and parentPath for new a NodePath (fixes an issue with export * from './a' and es2015-modules-commonjs).
    • babel-generator:
      • #3145 Always print "" in compact mode for consistency (gzip). Will be changed in a new mode (a supserset of compact) in a later patch.
      • #3146 Don't print comments in compact mode.
      • #3147 Don't print parentheses on throw statements with SequenceExpression.
  • Internal

    • babel-traverse:
      • #3138 Support UnaryExpression in isPure check.

6.3.15

  • Bug Fix
    • babel-generator:
      • #3111 Compact Mode: remove unnecessary () from a NewExpressions when possible (new x() -> new x).
    • babel-helper-function-name:
      • #3138 Skip name inference on certain uses of classes until we can handle them.
    • babel-traverse:
      • #3141 Fix bug with evaluating an expression on its own binding.
    • babel-plugin-transform-es2015-destructuring:
      • #3136 Seperate the destructuring statement from the export statement before converting.
    • babel-plugin-transform-es2015-classes:
      • #3134 Ensure default exports have a name before splitting them.
      • #3135 Pass async and generator properties when converting a ClassMethod.

6.3.14

  • Bug Fix
    • babel-traverse:
      • #3133 Fix regression with scope in switch statement (fixes an issue with transform-es2015-spread). Related to #3127.

6.3.8-6.3.13

Testing lerna - A tool for managing JavaScript projects with multiple packages.

  • Bug Fix
    • babylon, babel-types, babel-generator:
      • #3130 Add support for NullLiteralTypeAnnotation (null literal type) in flow.

6.3.2

  • Bug Fix
    • babel-core:
      • #3108 Omit sourcemaps that cannot be used and fix source path.
    • babel-register:
      • #3116 Disable processing .babelrc a second time.
    • babel-traverse:
      • #3127 Ensure we always push into a BlockStatement (fixes a babel-plugin-transform-class-properties issue).
    • babel-plugin-transform-class-properties:
      • #3113 Fix issue with using static class properties.
    • babel-plugin-transform-es2015-classes:
      • #3112 Fix issue with return super() in class constructor causing a super() hasn't been called error.
    • babel-plugin-transform-inline-environment-variables:
      • Fix typo with replaceWith.
    • babel-plugin-transform-regenerator:
      • #3119 Ensure that generator functions always have an Identifier (fixes an issue with exporting a generator as a default).

6.3.1

  • Bug Fix
    • babel-generator:
      • #3121 Fix spacing in binary expression when right is a binary expression and has a unary on the left in compact mode. Ex: (a+(+b*2)) should be -> a+ +b*2

6.3.0

  • Bug Fix

    • Fix use of old literal to use stringLiteral in babel-types.
    • Fix issue with babel-template crashing in IE due to unpopulated error stack.
    • Check for empty decorators list in transform-class-properties
    • Fix babylon parser not allowing multiple parameters in arrow functions with flow types
    • Fix exported async functions being hoisted and as a result being undefined.
  • Polish

    • Add validation to more JSX node types.
    • Add validation for CallExpression, NewExpression, SequenceExpression, ArrayExpression, and TemplateLiteral.
    • Add ObjectMember abstract type to AST for ObjectProperty and ObjectMethod.
    • Optimize asyncToGenerator helper template.
    • Respect spacing for assignment, binary expressions, and while loop in compact mode.
    • Fix up semicolon omission in compact mode.

6.2.2

  • Bug Fix
    • Fix ES2015 classes being revisited twice causing state issues when inside.

6.2.1

  • Polish
    • Add dirname to unknown plugin resolution error.

6.2.0

  • New Feature
    • Add support for function.sent.
  • Internal
    • Bump invariant depenency version.
  • Polish
    • Infer filename from the base directory when resolving plugins and presets.
    • Allow JSX pragma to be specified in line comments.
  • Bug Fix
    • Print a block when encountering consequents that are if statements.
    • Fix some issues related to printing of auxiliary comments.

6.1.21

  • Bug Fix
    • Add check to avoid revisiting classes.
  • Internal
    • Add internal aliases for plugins for debugging.
  • Bug Fix
    • Avoid duplicate auxiliary starts if inside an aux section.

6.1.20

  • Polish
    • Only infer whitespace when we've been passed tokens in the code generator.
    • Refactor JSX inlining to reduce parsing cost.
  • Bug Fix
    • Fix queueing of nested paths being pushed onto the priority queue.

6.1.19

  • Bug Fix
    • Add config check to package.json babel reading.
    • Fix source maps merging.
    • Ignore callee supers when doing spread compilation
    • Polish
    • Add hard error when we see decorators.

6.1.4

  • Bug Fix
    • Fix class transformation bug for export declarations with no id.
    • Fix regenerator plugin being passed an invalid function id.
    • Add support for async to generator helper on object and class methods.
    • Fix looking up undefined nodes when walking back up the tree in typeof symbol plugin.
    • Fix accidental serialisation of template literals in the code generator when the object of a member expression.
    • Add missing Expression alias to TypeCastExpression.
    • Move children prop pushing to after props to ensure correct order in the react inline elements plugin.
    • Fix buildExternalHelpers script ignoring non-underscored helpers.
    • Fix exported classes with static class properties.
  • Spec Compliancy
    • Add support for computed mutators in babel-plugin-transform-es2015-computed-properties.
  • Polish
    • Make interop for plugins with the __esModule work for all plugins no matter how they're imported/specified.
    • Make it illegal for plugins to specify a catch-all enter/exit visitor method.
    • Ignore babel-runtime version mismatch in babel-doctor.
    • Omit defaultProps helper when there are no props in the react inline elements plugin.
    • Add validators for ES2015 export nodes.
    • Add missing core node validators.
    • Update runtime plugin core-js definitions.
  • Internal
    • Add babel-plugin-transform-react-display-name to the react preset.
    • Clean up scope cache.
    • Move babel/register into a separate babel-register package.
    • Add react-jsx-source plugin and add it to the react preset.

6.1.3

  • Internal
    • Add allowTopLevelThis option to babel-plugin-transform-es2015-modules-commonjs.

6.1.2

  • Bug Fix
    • Fix bug where the parser wouldn't allow typed annotated default parametesr in arrow functions.
    • Add existence check to NodePath#has to ensure safeness when making comparisons.
    • Protect against replacing a class expression with a name inferred version that would result in it never being transformed.
    • When transforming JSX to an inline object, make sure invalid identifier keys are quoted.
    • Fix recursion in async to generator transforms due to referring to the inner generator function.
    • Convert arrow functions to normal functions when remapping to a generator.
    • Fix source map merging.
    • Add line break test to the updateContext of name tokens in the parser to fix parsing of JSX and regexs with ASI.
    • Fix object rest/spread in arrow function parameters not being allowed in the parser.
    • Ensure that unaries are parenthesised the same as function expressions.
  • Internal
    • Move Symbol.hasInstance transform out of babel-plugin-es2015-symbols to babel-plugin-es2015-instanceof as it has nothing to do with symbols.
    • Add babel-browser package with the browser build.
  • Polish
    • Add npm 3 check to babel-doctor.
    • Autoclear the babel/register cache when it gets too big to be serialised.
  • Spec Compliancy
    • Add support for flow existential type parameters.

6.1.1

  • Bug Fix
    • Stop looking for configs in babel-doctor when we get to the root.

6.1.0

  • New Feature
    • Add babel-doctor CLI.

6.0.20

  • Bug Fix
    • In the callable class constructor plugin, don't transform derived classes as the constructor call cannot be inherited.
    • Fix JSX inline elements plugin from attempting to create properties out of JSX containers.
    • Fix infinite recursion error when attempting to resolve the execution status of functions that contain references to themselves.

6.0.19

  • Bug Fix
    • Fix function paths not being accurate.
  • Polish
    • Change t.getOuterBindingIdentifiers to completely ignore function expressions as they cause no outer bindings to be set.
    • Clean up auxiliaryComment option.

6.0.18

  • Polish
    • Add error when calling builder methods with too many arguments than it can take.
    • Rename RegexLiteral node to RegExpLiteral.
    • Rename NumberLiteral node to NumericLiteral.
  • Bug Fix
    • Make all fields of a ForStatement optional.

6.0.17

  • Polish
    • Add Symbol existence check to typeof helper.
  • Bug Fix
    • When merging options, take precedence over the current array.
    • Fix export of parameters when renaming the binding of exported functions.
    • Fix minify booleans plugin.
    • Fix simplify comparison operator plugin.
    • Don't include children if it's empty in react inline elements plugin.

6.0.16

  • Internal
    • Instead of throwing on a foreign node path. Ignore it and create a new one.
  • Bug Fix
    • Ensure there's a newline after prepended original shebang.
    • Ignore non-origin template nodes when replacing placeholders in babel-template.
    • Fix runtime plugin helper generation.
    • Fix bug where async class methods weren't having their awaits converted to yields in the async to generator helper.

6.0.15

  • Bug Fix
    • Fix async function remap helper from outputing incorrect calls causing wrong scoping.

6.0.14

  • Spec Compliancy
    • Update exponentiation operator precedence.
    • Fix parser bug where arrow functions have a higher precedence than they should.
  • Bug Fix
    • Fix SystemJS module formatter exporting function parameters.
    • Ensure that invalid identifier JSX attribute keys are quoted when transforming to calls.
    • Fix ES3 property literal plugin.
    • Fix parameters after defaults in arrow functions refering to the wrong arguments.

6.0.13

  • Bug Fix
    • Don't consider uncomputed object method property identifier to be a reference.

6.0.12

  • Bug Fix
    • Rename misspelt babel-plugin-transform-class-constructor-call package.
    • Add strict mode plugin to module transforms.
    • Only ignore cloning of plugin instances when cloning babelrc configs.
    • Add shebang to bin file in babel complain package.
    • Remove asserts from babel-transform-regenerator as we may have multiple packages interacting.
    • Add babel-plugin-transform-es2015-modules-commonjs to babel-preset-es2015.

6.0.0

  • Internal
    • Split up internals into packages.
  • Breaking Change
    • Remove loose option in favor of plugin options.
    • Remove optional, whitelist and blacklist options since plugins are now explicitly defined.
    • Plugins now just return a plain object rather than construct a Plugin instance.
    • Change the signature of visitor methods to .call(state, path, state) rather than .call(path, node, parent, scope, state).
    • All plugin traversals are now merged for performance.
    • The MethodDefinition node type has been renamed to ClassMethod and it's FunctionExpression value property has been coerced into the main method node.
    • The Property node type has been renamed to ObjectProperty.
    • The Property node type with the boolean flag method has been renamed to ObjectMethod and it's FunctionExpression value property has been coerced into the main method node.
    • The Literal node type has been unoverloaded and split into BooleanLiteral, RegExpLiteral, NumericLiteral, StringLiteral and NullLiteral.
    • The SpreadProperty (from object-rest-spread) node type has been split into RestProperty (for ObjectPattern) and SpreadProperty (for ObjectExpression)
    • Remove module.exports export interop for CommonJS module formatter.
    • externalHelpers option has been moved into the plugin babel-plugin-external-helpers-2.
    • Remove ability to use enter/exit catch-all handlers in plugins.
  • New Feature
    • Add plugin options.
    • Add callable class constructor.

5.8.26

  • Internal
    • Republish to get fix for runtime typeof-react-element helper.

5.8.25

  • Internal
    • Rename define method to avoid webpack assuming those files are AMD.

5.8.24

  • Spec Compliancy
    • Updated optimisation.react.inlineElements transformer to React 0.14 output. Thanks @spicyj!
  • Polish
    • Add support for evaluating more static nodes. Thanks @hzoo!

5.8.23

  • Bug Fix
    • Fix a bug where pushed scope bindings weren't properly being registered.

5.8.22

  • Bug Fix
    • Fix bug causing regexes to cause a syntax error after a block.
  • Internal
    • Expose File.

5.8.21

  • New Feature
    • Add support for Flow export types.
  • Bug Fix
    • Fix flow type annotations on object properties being lost.
    • Fix bug effecting nested arrow functions.
    • Check valid export default function/class token when parsing export default before converting to a declaration to avoid turning expressions into declarations.
  • Polish
    • Add an exception to non-existent bindings when checking if we need to wrap block scoping blocks in a closure.
    • Make comment retainment for multiple replacement nodes more predictable.
  • Internal
    • Remove operator property from AssignmentPattern nodes.
    • Update es7.asyncFunctions and es7.objectRestSpread to stage 2.

5.8.13-5.8.20

The CHANGELOG was broken for these releases. Git tags were not pushed in the correct order and are therefore incorrect. It's recommended you NOT use any versions within this range.

  • New Feature
    • Add es6.spec.modules transformer.
  • Bug Fix
    • Don't register export declarations as a module binding.
    • Register import bindings to the specifier instead of the declaration.
    • export * should not export default.
    • Clear `rawValue from JSX attribute values to avoid outputting the raw source verbatim.
    • Add support for boolean flow literals.
    • Fix bug where files that babel can compile weren't being written when ignored with the --copy-files flag.
    • Create new raw identifiers instead of cloning the original user one when exploding export specifiers to fix source map issues resulting in incorrect locations.
    • Break on hitting a terminator paren triggering character to avoid pushing multiple starting parens.
    • Consider comment starting character to be a terminatorless separator to avoid starting comments breaking terminatorless nodes.
  • Internal
    • Use json5 for parsing .babelrc files and JSON for package.json.
    • Update Regenerator dependency to 0.8.35.
    • Remove flow types from being scope tracked.
  • Polish
    • Only register export declarations in scope tracking if they're of a valid type.
    • Only output code frame and message on syntax errors in CLI.
    • Set decorated initialisers that have no initialiser to undefined.
    • Optimise common typeof cases in es6.spec.symbols transformer.

5.8.12

  • Bug Fix
    • Fix bug in lookahead causing decorators to be cleared.

5.8.11

  • Bug Fix
    • Check if module options are nully instead of falsy to allow empty strings as moduleRoot etc.
    • Fix bug where reassigning the rest parameter wouldn't result in a deoptimisation.

5.8.9

  • Bug Fix
    • Fix issue in parser where the flow plugin wasn't using state to refer to whether it as in a type or not causing lookaheads to cause breakages.

5.8.8

  • Bug Fix
    • Fix comments not being attached if they're touching the start of their node.

5.8.7

  • Never published, environment issues, again.

5.8.6

  • Bug Fix
    • Remove rawValue for JSX inner text.

5.8.5

  • Polish
    • Rewrite parentheses insertion for terminatorless nodes such as BreakStatement to be much more stable and cleaner.
    • Use Object.setPrototypeOf and fallback to __proto__ in inherits helper.

5.8.2-5.8.4

Issues with publish process.

5.8.1

  • Bug Fix
    • Fix regression where async arrow functions couldn't have type annotation parameters.
    • Output type annotations of type instantiation parameters.
  • Polish
    • Prepend to highest loop when performing rest parameter allocation optimisation.
    • Add comment attachment to parser.
    • Add support for retaining inner comments of empty blocks.

5.8.0

  • Never released due to publish environment issues.

5.7.4

  • Bug Fix
    • Fix comments containg @flow being completely removed from output rather than just the specific directive.

5.7.3

  • Bug Fix
    • Add shim file for broken file path that old versions of the CLI would attempt to use.

5.7.2

  • Bug Fix
    • Fix performance issue in code generator when comment columns would attempt to match up in compact mode causing large amounts of whitespace.
    • Fix single line comments not outputting a newline in compact mode.
  • Polish
    • Add support for flow return types for arrow functions.

5.7.1

  • Bug Fix
    • Add back mistakenly removed replaceWithSourceString method.

5.7.0

  • Bug Fix
    • Deopt on spread elements when performing array destructuring unpack optimisation.
  • New Feature
    • Add shouldPrintComment option to control comment output.
    • Add .babelignore file to be consistent with other tools.
    • Allow .babelrc configs to be specified via package.json.
  • Polish
    • Don't ignore comments when using compact: true option.
    • Add support for Flow import typeof.
    • Fix incorrect inheritance method position when using loose mode classes and constructor isn't the first item.
  • Internal
    • Completely fork Acorn with babylon.
    • Rewrite build system to accommodate for multiple packages.

5.6.17

  • Bug Fix
    • Fix CodeGenerator.findCommonStringDelimiter causing a stack overflow.

5.6.16

  • Internal
    • Fix recast version to avoid pulling in a newer version.
  • New Feature
    • Add support for functions in util.shouldIgnore.
  • Polish
    • Strip flow directives in flow transformer.
    • Add a check for out of bounds default parameters, drastically improving performance and removes engine deoptimisations.
    • Various performance optimisations by @samccone πŸ’…βœ¨
    • Delay this assignment when referencing this inside an arrow function pre-bare super in derived class constructors.
    • Split up class body pushing if the constructor is in the wrong order.
  • Bug Fix
    • Fix hoisting of ForInStatement init variables in system module formatter.
    • PathHoister: Don't hoist to the same function as their original paths function parent.
    • PathHoister: Push each violation paths ancestry to the breakOnScopePaths collection to avoid constant hoisting to nested paths.fix tail call recursion on functions with less arguments than parameters.
    • Disallow super.* before super() in derived class constructors.
    • Properly regenerate scope for replaced nodes. Thanks @loganfsmyth!
    • Move up template literal simplification logic to avoid breaking on single elements.

5.6.13-5.6.15

  • Setting up automatic Travis releases.

5.6.12

  • Bug Fix
    • Fix finding parent for top-level shadowed functions.

5.6.11

** Internal

5.6.10

  • Bug Fix
    • Fix faulty internal require check.
  • Polish
    • Add support for trailing commas in arrow function parameter lists.

5.6.8

  • Bug Fix
    • Fix binary expressions colliding with unary expression operators in compact mode.
    • Fix node properties being set to null when using computed properties.

5.6.7

  • Bug Fix
    • Fix hoisting of ForXStatement left vars when inserting a block scoping IIFE.
  • Polish
    • Combine all leading computed property initialisers into the root object in loose mode.
  • Internal
    • Deprecate returning of replacement strings from visitor methods.

5.6.6

  • Bug Fix
    • Fix weird parser bug where void type annotations were being parsed as keywords causing the tokeniser to lose track of context.

5.6.5

  • Bug Fix
    • Fix nested functions causing rest parameter optimisation to not properly detect when it should deopt on a reference.
  • Internal
    • Update Regenerator 0.8.31.

5.6.4

  • Internal
    • Add ParenthesizedExpression node type.

5.6.3

  • Bug Fix
    • Fix rest parameter array allocation loop being incorrectly aliased.

5.6.2

  • Bug Fix
    • Fix method key literals not turning into computed member expression in loose mode.
    • Elect rest parameters in spread element position as candidates instead of replacing them in place.

5.6.0

  • Bug Fix
    • Fix istanbul interop for register hook when registering for non-existence extension.
    • Fix super class constructor call differing for no constructor in derived classes.
    • Disable module import receiver when in loose mode.
    • Fix duplicate filenames when using babel CLI when passing multiple matching patterns.
    • Register labels as bindings to fix undeclared variable checks.
  • Polish
    • Remove unnecessary string binary expressions when transforming template literals.
    • Support module live bindings in arbitary positions not in Program statement position.
    • Throw error when attemping to replace a Program root node with another node not of type Program.
    • Optimise rest parameters in spread element position and allocate rest array at the earliest common ancestor of all references.
    • Generate original number representation when value was not changed.
    • Check for invalid binding identifiers when generating inferred method names.
    • Don't terminate CLI when watching files fail compilation on init.
  • New Feature
    • Add new plugin API.
  • Internal
    • Split react displayName addition into a plugin.
    • Add check for JSXMemberExpression to t.isReferenced.
    • Move validation.undeclaredVariableCheck transformer up.
    • Start great core-to-plugin exodus.
    • Add BindingIdentifier virtual type.
    • Hidden class optimisations.
    • Array allocation optimisations.
    • Update regenerator.
    • Update js-tokens.
    • Sync with upstream Acorn.

5.5.8

  • Internal
    • Remove extremely unprofessional and harsh error message for those hotlinking to resolve-rc.

5.5.7

  • Bug Fix
    • Push newline after decorators when doing code gen.
    • Rewriting error handling to normalise options before merging them.
    • Remove duplicate keys in alias-keys.json causing errors in strict mode.
    • Fix $ babel --help not showing optional transformers as such.
  • New Feature
    • Add auxiliaryCommentBefore and auxiliaryCommentAfter options.

5.5.6

  • Bug Fix
    • Fix let binding collision in loop head not properly replacing AssignmentExpressions.

5.5.5

  • Bug Fix
    • Fix file.opts not being set before file.log.deprecate was called causing a ReferenceError as it was checking for a property on it.

5.5.4

  • Bug Fix
    • Add back missing shouldIgnore check.
    • Log message on deprecated options rather than throw an error.
    • Fix name of auxiliaryComment option when attempting Istanbul interop in babel/register.

5.5.3

  • Bug Fix
    • Fix weird state bug when traversing overa node ClassProperty instead of path in the es6.classes transformer.

5.5.2

  • Bug Fix
    • Fix NodePath#isPure on Property nodes.
    • Use cwd instead of entry file directory when working out relative directory for babel/register.
  • Internal
    • Add scary warning for those few who choose to use the WIP experimental transformers.

5.5.1

  • Bug Fix
    • Remove ClassProperty nodes always in the Flow transformer. This is fine now since class properties aren't supported in any engine that supports classes but the es7.classProperties transformer will need to be updated in the future to desugar to ES6 classes instead of relying on the es6.classes transformer from being ran.

5.5.0

  • Bug Fix
    • Allow pushing declarations to SwitchStatements.
    • Fix minification.removeDebugger to remove DebuggerStatements rather than ExpressionStatements with an identifier of debugger.
    • Check LHS in ForInStatement and ForOfStatement for constant violations.
    • Register function id as a reference when naming methods to avoid collisions.
    • Support key literals when checking for the existence of displayName property when attempting to add it for React.createClass.
    • Remove ExportDefaultSpecifier check from t.isDefaultSpecifier.
    • Don't consider JSXIdentifier HTML tag identifiers to be references.
  • Polish
    • Update minification.deadCodeElimination transformer to remove all statements after completion statements.
    • Update minification.deadCodeElimination transformer to not inline single used bindings that exist in different scopes.
    • When performing Istanbul interop in babel/register, add the auxiliary comment "istanbul ignore text" to get more accurate coverage.
    • Add --nolazy argument to babel-node.
    • Add support for cluster forking.
    • Perform scope tracking in a single pass instead of multiple.
    • Smarten up type inferrence and resolution to support the whole array of language constructs.
    • Optimise module metadata retrieval into a single pass.
    • Ignore trailing commas when inferring newlines.
    • Rename minification.inlineExpressions transformer to minification.constantFolding.
    • Check path relative to entry file when checking to see if we're inside node_modules when using babel/register.
    • Upgrade regenerator.

5.4.7

  • Bug Fix
    • Don't consider JSXAttribute names to be valid ReferencedIdentifiers.

5.4.6

  • Bug Fix
    • Fix spec.functionName transformer incorrectly attempting to rename a binding that doesn't exist as it's a global.
  • Internal
    • Deprecate custom module formatters.

5.4.5

  • Bug Fix
    • Add JSXIdentifier as a valid ReferencedIdentifier visitor virtual type.
    • Ignore CallExpression _prettyCall when the retainLines option is enabled.
    • Inherit comments to new declaration node when exploding module declarations.
    • Fix es6.tailCall transformer failing on calls that exceed the max parameters of the function.

5.4.4

  • Bug Fix
    • Fix bug where replacing variable declarations in the head of a for loop would turn them into ExpressionStatements.
    • Fix renaming of assignment expressions that were non-identifiers ie. patterns.
    • Force space before class id to avoid breaking named classes when using compact mode.
    • Add assignment pattern explosion to avoid initial duplicate nodes.
    • Ignore this and arguments when performing TCO on shadowed functions.
  • Polish
    • Rename sourceMapName option to sourceMapTarget. Thanks @getify!
    • Better detection of completion records, ignore those in Functions.
    • Clarified descriptions of the options that are enabled by default.
    • Resolve \babel-plugin-${name}`plugin names **before** just checking thename`. Thanks @jquense!
    • Update AMD module formatter to add import default remapping.

5.4.3

  • Bug Fix
    • Fix module being incorrectly rewritten when used as in an export declaration.
    • When performing single-reference inlining, ensure that the single reference isn't a child of the binding itself.
    • Fix a bug in minification.deadCodeElimination where a new binding instance was being created for local class bindings instead of just inheriting the parent one.
    • Fix bug with paren printing in compact and retainLines mode where a left paren was already printed before catching up.
  • Internal
    • Handle contexts for paths much better. This will ensure that the path node location info is in sync.

5.4.2

  • Polish
    • ignore and only patterns are now very liberal. The pattern can now exist anywhere in the path.

5.4.1

  • Bug Fix
  • Polish
    • Clean up shouldIgnore algorithm to work how you'd expect rather than being a hacky piece of shit. It now crawls the entire path, checking each section of it against the input ignore/only patterns. This means that the pattern foo will ignore the paths foo/bar.js, bar/foo etc.

5.4.0

  • New Feature
  • Bug Fix
    • Fix files not properly being ignored when babel.transform ignores them when using $ babel.
    • Fix scope tracking registering loop head bindings to their VariableDeclaration instead of VariableDeclarator.
  • Polish
    • Normalise path separators for souce map paths when using $ babel.
    • Rework PathHoister to ignore global references and to not deopt on reassignments to referenced bindings, instead it tries to hoist to the highest scope.
    • Added missing exponential operator inlining. Thanks @nkt!
    • Optimise regenerator transformer. Thanks @benjamn!

5.3.3

  • Bug Fix
    • Fix minification.deadCodeElimination transformer incorrectly trying to inline import declarations.
    • Fix minification.inlineExpression transformer getting into an infinite loop.

5.3.2

  • Bug Fix
    • Fix patterns not being considered when hoisting variables in the es6.blockScoping transformer.

5.3.1

  • Bug Fix
    • Fix unique export specifiers not being cloned when exploding class and function exports,
  • Polish
    • Turn import remaps to sequence expressions to remove their context and improve performance.

5.3.0

Speeeeeeed

gifs lol

  • Spec Compliancy
    • Allow trailing param commas for methods when using the es7.trailingCommas transformer.
  • Bug Fix
    • Fix es6.blockScoping transformer not properly ignoring break in SwitchCase.
    • Fix lookahead context saving to avoid weird tokenizer state.
    • Explode duplicate identifiers in export/import specifiers and property shorthand to create unique objects.
    • Skip loose mode for class methods when they have decorators.
    • When removing nodes, share their comments with their siblings.
    • Properly hoist temp param declarations when doing TCO.
  • Internal
    • Add --harmony_generators flag to $ babel-node.
    • Internal AST traversals have been minimised drastically. Transformers have been grouped together which means entire tree traversals are much fewer. Visiting nodes is now also skipped if the traversal context can detect that the handler is a noop. This sames precious cycles as it avoids constructing traversal paths and creating a new traversal context. See issues #1472 and #1486 for related discussion.
  • Polish
    • Move many utility transformers to minification.

5.2.17

  • Bug Fix
    • Fix auxiliary comments not properly being attached to function declaration helpers.
    • Add Super node type to ast-types patch.
    • Ignore parameter bindings when attempting to inline them in the minification.deadCodeElimination transformer.
    • Correct extensions arguments when using the Babel CLI.

5.2.16

  • Bug Fix
    • Fix plugins being disabled when using the whitelist.
    • Fix correct function scope being passed to nameMethod.property when inferring the function name for class methods.
    • Fix incorrect extensions reference causing weird issues when using the Babel CLI.
    • Fix destructuring param reference replacements not inheriting from their original param.
  • Spec Compliancy
    • Fix order that method decorators are ran in.

5.2.15

  • Bug Fix
    • Fix initializer descriptor add attempt if it doesn't exist.

5.2.14

  • Bug Fix
    • Fix bug with initializer decorators where the descriptors weren't being defined if there was no initializer property.
  • Internal
    • Expose retainLines option to CLI.
    • Fix retainLines option not being taken into consideration when doing multiple variable declaration declarators generation.
    • Expose minified and unminified copies of dist scripts.

5.2.13

  • Bug Fix
    • Fix ExportDeclarations being incorrectly removed when using the utility.deadCodeElimination transformer.
    • Fix position of utility transformers.
  • New Feature
    • Add built-in esquery support.
  • Internal
    • Consolidate notion of "virtual types".

5.2.12

  • Polish
    • Make UID generation based on module declarations much nicer.
  • Internal
    • Remove internal check for traversal path replacement of self. This is a pattern that could come up in the wild and it could lead to pretty nasty code and may lead to internal regressions as the test coverage isn't 100% :( Instead, just put it in the fast path.

5.2.11

  • Internal
    • Rename getModuleName option to getModuleId, doh.

5.2.10

  • Bug Fix
    • Fix numerous issues in replaceWithSourceString. Thanks @pangratz!
  • New Feature

5.2.9

  • Bug Fix
    • Fix _blockHoist transformer incorrectly sorting nodes on shitty environments that aren't spec compliant in their key order.
    • Fix broken parse API method reference to an undeclared import.

5.2.7

  • Bug Fix
    • Move utility.deadCodeElimination transformer up to avoid race conditions.
    • Fix shorthand property scope binding renaming.
  • Polish
    • Turn helper variable declarations into function declarations if possible.
  • Internal
    • Removed native inheritance support from classes.
    • Added replaceWithSourceString path API.
    • Split up es3.propertyLiterals and es3.memberExpressionLiterals transformers to minfication.propertyLiterals and es3.memberExpressionLiterals.

5.2.6

  • Internal
    • Fix transformer aliases being accidently set as deprecated ones.
    • Expose Pipeline as TransformerPipeline instead.

5.2.5

  • Bug Fix
    • Fix parse API not adding all the correct pipeline transformers.

5.2.4

  • Bug Fix
    • Fix race condition with the Node API being loaded awkwardly and not being able to initialise itself when used in the browser.
  • Internal
    • Expose transform.pipeline.

5.2.3

  • Bug Fix
    • Fix plugin containers being called with an undefined import. Thanks @timbur!
    • Allow Flow object separators to be commas. Thanks @monsanto!
    • Add missing Statement and Declaration node aliases to flow types.

5.2.2

  • Internal
    • Allow util.arrayify to take arbitrary types and coerce it into an array.

5.2.1

  • Bug Fix
    • Fix regression in node/register that caused node_modules to not be ignored.

5.2.0

  • Bug Fix
    • Fix plugin strings splitting arbitrarily on : which caused full paths on Windows to fail as they include : after the drive letter.
    • Call class property initializers with their target instead of their descriptor.
    • Fix ignore and only not properly working on Windows path separators. Thanks @stagas!
    • Fix resolveRc running on files twice causing issues. Thanks @lukescott!
    • Fix shorthand properties not correctly being target for isReferenced checks. Thanks @monsanto!
  • Polish
    • Allow passing an array of globs to babel/register only and ignore options. Thanks @Mark-Simulacrum!
    • When inferring function names that collide with upper bindings, instead of doing the wrapper, instead rename them.
    • Consider constant-like variable declaration functions to always refer to themselves so TOC can be performed.
    • Process globs manually when using $ babel as some shells such as Windows don't explode them. Thanks @jden!
    • Add alternative way to execute plugins via a closure that's called with the current Babel instance.
  • Internal
    • Remove multiple internal transformers in favor of directly doing things when we need to. Previously, declarations such as _ref that we needed to create in specific scopes were done at the very end via the _declarations transformer. Now, they're done and added to the scope right when they're needed. This gets rid of the crappy _declarations property on scope nodes and fixes the crappy regenerator bug where it was creating a new BlockStatement so the declarations were being lost.
    • Rework transformer traversal optimisation. Turns out that calling a check function for every single node in the AST is ridiculously expensive. 300,000 nodes timesed by ~30 transformers meant that it took tens of seconds to perform while it's quicker to just do the unnecessary traversal. Seems obvious in hindsight.
  • New Feature
    • Add jscript transformer that turns named function expressions into function declarations to get around JScript's horribly broken function expression semantics. Thanks @kondi!
    • Add @@hasInstance support to objects when using the es6.spec.symbols transformer.
    • Add retainLines option that retains the line (but not the columns!) of the input code.

5.1.13

  • Polish
    • Remove symbol check from defineProperty helper.

5.1.12

  • Bug Fix
    • Fix resolveModuleSource not being ran on ExportAllDeclarations.
    • Fix .babelrc being resolved multiple times when using the require hook.
    • Fix parse error on spread properties in assignment position.
    • Fix externalHelpers option being incorrectly listed as type string.
  • Internal
    • Upgrade core-js to 0.9.0.
  • Spec Compliancy
    • Fix object decorators not using the initializer pattern.
    • Remove property initializer descriptor reflection.

5.1.11

  • Bug Fix
    • Memoise and bind member expression decorators.
    • Move JSX children cleaning to opening element visitor. Fixes elements not being cleaned in certain scenarios.
    • Consider SwitchStatements to be Scopable.
    • Fix bluebirdCoroutines calling interopRequireWildcard before it's defined.
    • Add space to do...while code generation.
    • Validate super use before this on super exit rather than entrance.
  • Polish
    • Add Babel name to logger.

5.1.10

  • Bug Fix
    • Remove makePredicate from acorn in favor of an indexOf.
    • Remove statements to expression explosion when inserting a block statement.
  • Internal
    • Remove runtime compatibility check.

5.1.9

  • Bug Fix
    • Fix class property initializers with undefined values not being correctly writable.
    • Fix self inferring generators incorrectly causing a stack error.
    • Fix default export specifiers not triggering AMD module argument inclusion.
    • Fix assignments not having their module references properly remapped.
  • Internal
    • Upgrade to latest acorn.
  • Polish
    • Make invalid LHS pattern error messages nicer.

5.1.8

  • Bug Fix
    • Only make parenthesized object pattern LHS illegal.

5.1.7

  • Internal
    • Add parse node API.

5.1.6

  • Bug Fix
    • Fix runtime built-in catchall not properly checking for local variables.

5.1.5

  • Internal
    • Bump core-js version.

5.1.4

  • Polish
    • Add missing Reflect methods to runtime transformer.

5.1.3

  • Internal
    • Switch entirely to vanilla regenerator.
    • Clean up and make the parsing of decorators stateless.
  • Bug Fix
    • Don't do TCO on generators and async functions.
    • Add missing core-js runtime definitions.

5.1.2

  • Bug Fix
    • Add getIterator and isIterable to babel-runtime build script.

5.1.1

  • Bug Fix
    • Add missing runtime symbol definitions.

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.
    • Add missing test declaration to utility.deadCodeElimination transformer.
  • 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 inits 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

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!

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
    • Make relative location absolute before calling resolveRc.
  • Internal
    • Switch to global UID registry.
    • Add breakConfig option to prevent Babel from erroring when hitting that option.

5.0.1

  • Bug Fix
    • Fix duplicate declaration regression.
    • Fix not being able to call non-writable methods.

5.0.0

  • New Feature
    • Decorators based on @wycat's stage 1 proposal.
    • Class property initializers based on @jeffmo's stage 0 proposal.
    • Export extensions based on @leebyron's stage 1 proposal.
    • UMD module formatter now supports globals.
    • Add es3.runtime, optimisation.react.inlineElements and optimisation.react.constantElements transformers.
    • Add stage option that replaces the experimental one.
    • Allow ES7 transformer to be enabled via optional instead of only via stage.
    • Infer string quotes to use in the code generator.
    • Consider export { foo as default }; to be the same as export default foo;.
    • Add nonStandard option that can be set to false to remove parser support for JSX and Flow.
    • Add jsxPragma option.
    • Automatically generate CLI options based on internal API options.
    • Add support for .babelrc on absolute paths.
    • Plugin API!
  • Internal
    • Export options in browser API.
    • Rewritten parser.
    • Don't block hoist when runtime transformer is enabled in system module formatter.
    • Rewritten the internal traversal and node replacement API to use "paths" that abstracts out node relationships.
  • Polish
    • JSX output is now more inline with the official JSX transformer.
    • Hoist block scoping IIFE - this improves memory usage and performance.
    • Better IIFE detection - references are now checked to see if they're referencing the binding we're searching for.
    • Check for import reassignments in constants transformer.
    • Make method definitions with expression bodies illegal.
    • Save register cache on tick instead of SIGINT.
    • Enable strict mode on babel-node eval flag.
  • Bug Fixes
    • Add support for live bindings. This change also increases the reliablity of export specifier renaming.
    • Add support for super update and non equals assignment expressions.
    • Rename shadow constructor binding in classes.
    • Seed next iteration bindings with previous fresh bindings when reassinging loop block scoped variables.
    • Fix new expression spread referencing the wrong constructor.
    • Call resolveModuleSource on dynamic imports.
    • Added param to list of duplicate declaration kinds.
  • Breaking Changes
    • The Babel playground has been removed.
    • ES7 Abstract References have been removed.
    • Experimental option has been removed in favor of a stage option.
    • Rename returnUsedHelpers to metadataUsedHelpers.

4.7.16

  • Bug Fix
    • Fix constructor spreading of typed arrays.
    • Fix break/continue/return aliasing of non-loops in block scoping transformer.

4.7.15

  • Bug Fix
    • Fix constructor spreading of collections.

4.7.14

  • Bug Fix
    • Fix constructor spreading of Promise.
  • Internal
    • Deprecate remaining playground transformers and abstract references.

4.7.13

  • Bug Fix
    • Handle comments on use strict directives.
    • Fix assignment patterns with a left side pattern.
  • Polish
    • Special case this when doing expression memoisation.

4.7.12

  • Bug Fix
    • Deprecate playground.methodBinding.

4.7.11

  • Bug Fix
    • Fix unicode regexes stripping their unicode flag before being passed on two regexpu.

4.7.10

  • Internal
    • Deprecate playground.methodBinding and playground.objectGetterMemoization.
  • Bug Fix

4.7.9

  • Polish
    • Allow inputSourceMap to be set to false to skip the source map inference.
    • Infer computed literal property names.
  • Bug Fix
    • Fix nested labeled for-ofs.
    • Fix block scoping break colliding with the parent switch case.
  • Internal
    • Upgrade acorn-babel.

4.7.8

  • Bug Fix
    • Fix computed classes not properly setting symbols.

4.7.7

  • Bug Fix
    • Fix types API exposure.

4.7.6

  • Bug Fix
    • Fix non-Identifier/Literal computed class methods.
  • Polish
    • Add a fallback if stack on an error is unconfigurable.
    • Hoist esModule module declarations to the top of the file to handle circular dependencies better.

4.7.5

  • Bug Fix
    • Don't remapbreaks to call the iterator return.
  • Polish
    • Use a different helper for computed classes for much nicer output. Also fixes a bug in symbols being non-enumerable so they wouldn't be set on the class.

4.7.4

  • Bug Fix
    • Rewrite named function expressions in optional async function transformers.
    • Hoist directives.
    • Remove Number from the list of valid runtime constructors.
  • Internal
    • spec.typeofSymbol transformer has been renamed to es6.symbols.

4.7.2

  • New Feature
  • Bug Fix
    • Fix node duplication sometimes resulting in a recursion error.
    • Ignore breaks within cases inside for...of.
  • Polish
    • Split up variable declarations and export declarations to allow easier transformation.

4.7.0

  • Bug Fix
    • Add alternate to list of STATEMENT_OR_BLOCK keys.
    • Add support for module specifiers to t.isReferenced.
  • New Feature
    • Add inputSourceMap option.
  • Polish
    • Throw an error on different babel and babel-runtime versions.
    • Replicate module environment for babel-node eval.
    • Clean up classes output.
  • Spec Compliancy
    • Make it illegal to use a rest parameter on a setter.

4.6.6

  • Bug Fix
    • Fix incorrect method call in utility.deadCodeElimination transformer.
    • Fix es6.blockScopingTDZ transformer duplicating binding nodes.

4.6.5

  • Internal
    • useStrict transformer has been renamed to strict.

4.6.4

  • Bug Fix
    • Fix ForOfStatement not proplery inheriting labels.
    • When in closure mode in block scoping transformer, properly check for variable shadowing.
  • New Feature
    • New utility.inlineEnvironmentVariables and utility.inlineExpression transformers.

4.6.3

  • Bug Fix
    • Fix arguments being incorrectly aliased in arrow function rest parameter optimisation.
    • Make deoptimisation trigger safer.
  • New Feature
    • Flow types are now retained when blacklisting the flow transformer.

4.6.1

  • Bug Fix
    • Fix generators in template directory being transformed.
    • Fix exposure of util for plugins.

4.6.0

  • New Feature
    • Desugar sticky regexes to a new constructor expression so it can be handled by a polyfill.
  • Spec Compliancy
  • Polish
    • Rest parameters that are only refered to via number properties on member expressions are desugared into a direct arguments reference. Thanks @neVERberleRfellerER!
    • $ babel no longer exits on syntax errors.
  • Internal
    • Upgrade browserify.
    • Upgrade source-map.
    • Publicly expose more internals.

4.5.5

  • Polish
    • Delete old extensions when overriding them in babel/register.

4.5.3

  • Bug Fix
    • Fix whitelisting logic for helper build script.

4.5.2

  • New Feature
    • returnUsedHelpers option and add whitelist to buildHelpers.
  • Bug Fix
    • Fix function arity on self referencing inferred named functions.
  • Internal
    • Bump acorn-babel.
    • Start converting source to ES6...

4.5.1

Babel now compiles itself!

holy shit

4.5.0

  • New Feature
    • Add .babelrc support.
  • Bug Fix
    • Move use strict directives to the module formatter bodies.
  • Internal
    • Make default bin/babel behaviour to ignore non-compilable files and add a --copy-files flag to revert to the old behaviour.

4.4.6

  • Bug Fix
    • Fix extending a class expression with no methods/only constructor. Thanks @neVERberleRfellerER!
    • Allow MemberExpression as a valid left of ForOfStatement.
  • Polish
    • Throw an error when people try and transpile code with the @jsx React.DOM pragma as it conflicts with the custom jsx constructo method detection.
    • Crawl all comments for @jsx pragma.
  • Internal
    • Upgrade chalk.
    • Upgrade core-js.

4.4.5

  • Internal
    • Remove function self reference optimisation.

4.4.4

  • Bug Fix
    • Handle inferred function ids to be reassigned and deopt to a slower but working equivalent.
    • Don't unpack array patterns that have more elements than their right hand array expression.
  • Polish
    • Improve syntax highlighting in the code frame. Thanks @lydell!
  • Internal
    • Upgrade acorn-babel.

4.4.3

  • Bug Fix
    • Fix for...of iterator break returns being duplicated.
    • Only call return on the iterator if it exists.
  • Internal
    • Rename selfContained transformer to runtime.

4.4.2

  • New Feature
    • Add moduleId option for specifying a custom module id.

4.4.0

  • New Feature
    • /*** @jsx NAMESPACE **/ comments are now honored by the react transformer.
    • getModuleName option.
    • Infer function expression names. Thanks @RReverser!
  • Bug Fix
    • Add proper control flow for tail recursion optimisation.
  • Internal
    • Remove useless format options and move the format.compact option to format.
  • Polish
    • Newline handling of the code generator has been heavily improved.
    • Code generator now deopts whitespace if the input size is >100KB.

4.3.0

  • Breaking Change
    • Remove commonStandard module formatter and make it the default behaviour of all the strict module formatters.

4.2.1

  • Polish
    • Add auxiliary comment to let scoping closure flow control.

4.2.0

  • Polish
    • Use an assignment instead of a define for __esModule in loose mode.
  • Internal
    • Add error for eval(); usage and enable strict mode for parsing.

4.1.0

  • New Feature
    • Add BABEL_CACHE_PATH and BABEL_DISABLE_CACHE environment variables.
  • Internal
    • Replace many internal util functions with modules. Thanks @sindresorhus!

4.0.2

  • Bug Fix
    • Fix generators not properly propagating their internal declarations.
  • Polish
    • Update setter param length error message.
    • Use ranges on dependencies.

4.0.0

  • 6to5 is now known as Babel.
  • Global helpers/runtime has now been given the more descriptive name of "external helpers".