v7.6.4

This reverts commit cc080417b9.

.flowconfig

@@ -24,4 +24,6 @@ suppress_comment= \\(.\\|\n\\)*\\$FlowIgnore
 suppress_type=$FlowFixMe
 suppress_type=$FlowSubtype
 esproposal.export_star_as=enable
+esproposal.optional_chaining=enable
+esproposal.nullish_coalescing=enable
 module.name_mapper='^@babel\/\([a-zA-Z0-9_\-]+\)$' -> '<PROJECT_ROOT>/packages/babel-\1/src/index'

.github/CHANGELOG-6to5.md

@@ -122,7 +122,7 @@
   * Restructure transformers so they're only ran if the AST contains nodes that they need to worry about. Improves transpilation speed significantly.
  * **Bug Fix**
   * Fix source maps not tracking end of node locations.
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Use static super references as the home object is actually done at definition time.
  * **Polish**
   * Force the `es6.destructuring` transformer to be whitelisted when the `es7.objectSpread` transformer is.
@@ -479,7 +479,7 @@
 
 ## 2.12.3
 
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Optional `typeof` transformer checks for `undefined` before passing it to the helper.
   * Class methods are now named.
 
@@ -551,7 +551,7 @@
   * Add `classesFastSuper` optional transformer that doesn't support parent getters and prototype changing.
   * Add `forOfFast` transformer that speeds up `for...of` on arrays but produces more code.
   * Add `--react-compat` to `bin/6to5`.
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Disallow setters without a single parameter.
   * Add `configurable` and `writable` to defined properties.
   * Use define instead of assignment for class methods.
@@ -619,7 +619,7 @@
 
 ## 2.7.0
 
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Disallow reassignments of imports.
  * **New Feature**
   * `reactCompat` option to enable pre-v0.12 react components.
@@ -662,7 +662,7 @@
  * **Polish**
   * Move `"use strict";` to inside module bodies instead of at the top of the file.
   * Better handling of dynamic imports.
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Class inheritance now has a `function` or `null` type check.
   * Add `interopRequireWildcard` around wildcard imports and exports to handle non-object exports.
 

.github/CHANGELOG-v4.md

@@ -110,7 +110,7 @@
   * Throw an error on different `babel` and `babel-runtime` versions.
   * Replicate module environment for `babel-node` eval.
   * Clean up classes output.
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Make it illegal to use a rest parameter on a setter.
 
 ## 4.6.6
@@ -150,8 +150,8 @@
 
  * **New Feature**
   * Desugar sticky regexes to a new constructor expression so it can be handled by a polyfill.
- * **Spec Compliancy**
-  * `for...of` now outputs in a lengthy `try...catch` this is to ensure spec compliancy in regards to iterator returns and abrupt completions. See [google/traceur-compiler#1773](https://github.com/google/traceur-compiler/issues/1773) and [babel/babel/#838](https://github.com/babel/babel/issues/838) for more information.
+ * **Spec Compliance**
+  * `for...of` now outputs in a lengthy `try...catch` this is to ensure spec compliance in regards to iterator returns and abrupt completions. See [google/traceur-compiler#1773](https://github.com/google/traceur-compiler/issues/1773) and [babel/babel/#838](https://github.com/babel/babel/issues/838) for more information.
  * **Polish**
   * Rest parameters that are only referred to via number properties on member expressions are desugared into a direct `arguments` reference. Thanks [@neVERberleRfellerER](https://github.com/neVERberleRfellerER)!
   * `$ babel` no longer exits on syntax errors.

.github/CHANGELOG-v5.md

@@ -12,7 +12,7 @@
 
 ## 5.8.24
 
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Updated `optimisation.react.inlineElements` transformer to React 0.14 output. Thanks [@spicyj](https://github.com/spicyj)!
  * **Polish**
   * Add support for evaluating more static nodes. Thanks [@hzoo](https://github.com/hzoo)!
@@ -451,7 +451,7 @@ Issues with publish process.
 
 ![gifs lol](https://31.media.tumblr.com/568205a0e37ae15eca510fa639589a59/tumblr_n8kw8kpcSb1sg6cg8o1_500.gif)
 
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Allow trailing param commas for methods when using the `es7.trailingCommas` transformer.
  * **Bug Fix**
   * Fix `es6.blockScoping` transformer not properly ignoring `break` in `SwitchCase`.
@@ -481,7 +481,7 @@ Issues with publish process.
   * 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**
+ * **Spec Compliance**
   * Fix order that method decorators are ran in.
 
 ## 5.2.15
@@ -616,7 +616,7 @@ Issues with publish process.
   * Fix `externalHelpers` option being incorrectly listed as type `string`.
  * **Internal**
   * Upgrade `core-js` to `0.9.0`.
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Fix object decorators not using the `initializer` pattern.
   * Remove property initializer descriptor reflection.
 

.github/CHANGELOG-v6.md

@@ -22,7 +22,7 @@
 > Backports for some folks (also other's when we accidentally merged PRs from both 6.x/master)
 > Lesson learned: just use `master` and backport on another branch.
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-core`, `babel-generator`, `babel-plugin-transform-flow-comments`, `babel-plugin-transform-flow-strip-types`, `babel-traverse`, `babel-types`
   * [#6081](https://github.com/babel/babel/pull/6081) Flow opaque type 6.x backport. ([@jbrown215](https://github.com/jbrown215))
 
@@ -1468,7 +1468,7 @@ It's a one-time use tool (helpful after the initial release when upgrading from
 
 ## v6.17.0 (2016-10-01)
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-preset-stage-2`, `babel-preset-stage-3`
   * [#4617](https://github.com/babel/babel/pull/4617) Move async-generators to stage-3. ([@hzoo](https://github.com/hzoo))
 
@@ -1476,7 +1476,7 @@ It's a one-time use tool (helpful after the initial release when upgrading from
 
 Specification repo: https://github.com/tc39/proposal-async-iteration
 
-Asynchronous Iteration was already added in [6.16.0](http://babeljs.io/blog/2016/09/28/6.16.0#spec-compliancy) under stage-2 but it was moved to stage-3 at the [latest TC-39 meeting](https://github.com/tc39/agendas/blob/master/2016/09.md#agenda-for-the-54th-meeting-of-ecma-tc39).
+Asynchronous Iteration was already added in [6.16.0](http://babeljs.io/blog/2016/09/28/6.16.0#spec-compliance) under stage-2 but it was moved to stage-3 at the [latest TC-39 meeting](https://github.com/tc39/agendas/blob/master/2016/09.md#agenda-for-the-54th-meeting-of-ecma-tc39).
 
 ```js
 // async generator syntax
@@ -1569,7 +1569,7 @@ First PR!
 
 Babel 6.16: Happy 2nd Birthday 🎂!
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 
 * `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](https://github.com/babel/babel/pull/3473) via [#4576](https://github.com/babel/babel/pull/4576) Implement support for async generator functions and for-await statements. ([@zenparsing](https://github.com/zenparsing))
@@ -2036,7 +2036,7 @@ It's also a lot folk's first PR (or first code PR)!
 * `babel-generator`, `babel-types`
   * [#3570](https://github.com/babel/babel/pull/3570) Add support for the new declare module.exports of flow. ([@danez](https://github.com/danez))
 
-#### Spec Compliancy
+#### Spec Compliance
 * `babel-plugin-transform-es2015-modules-amd`, `babel-plugin-transform-es2015-modules-commonjs`, `babel-plugin-transform-es2015-modules-umd`
   * [#3518](https://github.com/babel/babel/pull/3518) Throw error for multiple exports default. ([@kaicataldo](https://github.com/kaicataldo))
 
@@ -2332,7 +2332,7 @@ Length: The number of characters in the output code
 * `babel-plugin-transform-react-jsx-self`, `babel-preset-react`
   * [#3540](https://github.com/babel/babel/pull/3540) Added jsx-self babel transform plugin. ([@jimfb](https://github.com/jimfb))
 
-#### Spec Compliancy
+#### Spec Compliance
 * `babel-plugin-transform-es2015-unicode-regex`
   * [#3338](https://github.com/babel/babel/pull/3338) Update to `regexpu-core@2.0.0` for ES2016 compliance. ([@mathiasbynens](https://github.com/mathiasbynens))
 
@@ -3206,7 +3206,7 @@ Changes to note:
 - Reverting the class properties semicolon parser error.
 - Fix regression with plugin ordering with `babel-register`.
 
-#### Spec Compliancy
+#### Spec Compliance
 * `babel-plugin-transform-class-properties`, `babylon`
   * [#3332](https://github.com/babel/babel/pull/3332) Revert to standard ASI behavior for class properties. ([@loganfsmyth](https://github.com/loganfsmyth))
 
@@ -3628,7 +3628,7 @@ Thanks to @samwgoldman for all the new flow support!
  * `babel-plugin-transform-es2015-parameters`: [#3191](https://github.com/babel/babel/pull/3191) Fix the order of arguments initialization (fixes [T6809](http://phabricator.babeljs.io/T6809))
  * `babel-traverse`: [#3198](https://github.com/babel/babel/pull/3198) In `evaluate()`, it should not mistake lack of confidence for falsy
 
-* **Spec Compliancy**
+* **Spec Compliance**
  * `babylon`, `babel-generator`, `babel-plugin-transform-regenerator`: [#3190](https://github.com/babel/babel/pull/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](http://phabricator.babeljs.io/T6688)).
 
 * **Internal**
@@ -3863,7 +3863,7 @@ Thanks to @samwgoldman for all the new flow support!
   * 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**
+ * **Spec Compliance**
   * 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.
@@ -3904,7 +3904,7 @@ Thanks to @samwgoldman for all the new flow support!
  * **Polish**
   * Add npm 3 check to `babel-doctor`.
   * Autoclear the `babel/register` cache when it gets too big to be serialised.
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Add support for flow existential type parameters.
 
 ## 6.1.1
@@ -3969,7 +3969,7 @@ Thanks to @samwgoldman for all the new flow support!
 
 ## 6.0.14
 
- * **Spec Compliancy**
+ * **Spec Compliance**
   * Update exponentiation operator precedence.
   * Fix parser bug where arrow functions have a higher precedence than they should.
  * **Bug Fix**

.github/PULL_REQUEST_TEMPLATE.md

@@ -11,7 +11,7 @@ If you are making a change that should have a docs update: submit another PR to
 
 | Q                        | A <!--(Can use an emoji 👍) -->
 | ------------------------ | ---
-| Fixed Issues?            | `Fixes #1, Fixes #2` <!-- remove the (`) quotes to link the issues -->
+| Fixed Issues?            | `Fixes #1, Fixes #2` <!-- remove the (`) quotes and write "Fixes" before the number to link the issues -->
 | Patch: Bug Fix?          |
 | Major: Breaking Change?  |
 | Minor: New Feature?      |

.github/lock.yml

@@ -4,7 +4,7 @@
 daysUntilLock: 91
 # Comment to post before locking. Set to `false` to disable
 lockComment: false
-only: issues
+# The label to be applied when an issue is locked
 lockLabel: 'outdated'
 
 # Issues or pull requests with these labels will not be locked

.github/main.workflow

@@ -1,76 +0,0 @@
-workflow "Release" {
-  on = "push"
-  resolves = ["Trigger GitHub release"]
-}
-
-action "Is version tag" {
-  uses = "actions/bin/filter@0dbb077f64d0ec1068a644d25c71b1db66148a24"
-  args = "tag v*"
-}
-
-action "Is tag from master" {
-  uses = "babel/actions/commit-matches-branch@master"
-  needs = [
-    "Is version tag",
-  ]
-  args = "master"
-}
-
-action "Trigger GitHub release" {
-  uses = "babel/actions/trigger-github-release@master"
-  secrets = ["GITHUB_TOKEN"]
-  env = {
-    COMMIT_AUTHOR_NAME = "Babel Bot"
-    COMMIT_AUTHOR_EMAIL = "babel-bot@users.noreply.github.com"
-  }
-  needs = [
-    "Is version tag",
-    "Is tag from master",
-  ]
-}
-
-workflow "Welcome" {
-  resolves = [
-    "Create Welcome Comment"
-  ]
-  on = "issues"
-}
-
-action "Is action 'opened'" {
-  uses = "actions/bin/filter@master"
-  args = "action opened"
-}
-
-action "Create Welcome Comment" {
-  uses = "babel/actions/create-welcome-comment@master"
-  secrets = ["GITHUB_TOKEN", "BOT_TOKEN"]
-  needs = ["Is action 'opened'"]
-}
-
-workflow "Needs Info" {
-  resolves = [
-    "Create Needs Info Comment"
-  ]
-  on = "issues"
-}
-
-action "Is action 'labeled'" {
-  uses = "actions/bin/filter@master"
-  args = "action labeled"
-}
-
-action "Has label 'Needs Info'" {
-  uses = "actions/bin/filter@master"
-  needs = [
-    "Is action 'labeled'"
-  ]
-  args = "label 'Needs Info'"
-}
-
-action "Create Needs Info Comment" {
-  uses = "babel/actions/create-needs-info-comment@master"
-  needs = [
-    "Has label 'Needs Info'",
-  ]
-  secrets = ["BOT_TOKEN", "GITHUB_TOKEN"]
-}

.github/workflows/issue-triage.yml

@@ -0,0 +1,81 @@
+name: Issue Triage
+
+on:
+  issues:
+    types: [opened, labeled]
+
+jobs:
+  welcome:
+    name: Welcome comment
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check if Babel member
+        id: is_babel_member
+        if: github.event.action == 'opened'
+        uses: babel/actions/is-org-member@v2
+        with:
+          org: babel
+          username: ${{ github.event.issue.user.login }}
+          token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Create Welcome Comment
+        uses: babel/actions/create-comment@v2
+        if: |
+          github.event.action == 'opened' &&
+          steps.is_babel_member.outputs.result == 0
+        with:
+          token: ${{ secrets.BOT_TOKEN }}
+          issue: ${{ github.event.issue.number }}
+          comment: >
+            Hey @${{ github.event.issue.user.login }}!
+            We really appreciate you taking the time to report an issue. The 
+            collaborators on this project attempt to help as many people as 
+            possible, but we're a limited number of volunteers, so it's 
+            possible this won't be addressed swiftly.
+
+
+            If you need any help, or just have general Babel or JavaScript questions, we have a 
+            vibrant [Slack community](https://babeljs.slack.com) that typically always has someone 
+            willing to help. You can sign-up [here](https://slack.babeljs.io/) for an invite."
+
+  needs_info:
+    name: Needs Info
+    runs-on: ubuntu-latest
+    steps:
+      - name: Create Needs Info Comment
+        uses: babel/actions/create-comment@v2
+        if: |
+          github.event.action == 'labeled' &&
+          github.event.label.name == 'Needs Info'
+        with:
+          token: ${{ secrets.BOT_TOKEN }}
+          issue: ${{ github.event.issue.number }}
+          comment: >
+            Hi @${{ github.event.issue.user.login }}!
+            This issue is missing some important information we'll need
+            to be able to reproduce this issue.
+
+
+            Please understand that we receive a high volume of issues,
+            and there are only a limited number of volunteers that help
+            maintain this project. The easier it is for us to decipher an
+            issue with the info provided, the more likely it is that we'll
+            be able to help.
+
+
+            Please make sure you have the following information documented in
+            this ticket:
+            
+            1. Your Babel configuration (typically from `.babelrc` or `babel.config.js`)
+
+            2. The current (incorrect) behavior you're seeing
+
+            3. The behavior you expect
+
+            4. A [short, self-contained example](http://sscce.org/)
+
+
+            Please provide either a link to the problem via the
+            [`repl`](https://babeljs.io/repl/), or if the `repl` is
+            insufficient, a new and minimal repository with instructions on
+            how to build/replicate the issue.
+        

.github/workflows/release.yml

@@ -0,0 +1,53 @@
+name: Release
+
+on:
+  push:
+    tags: ["v*"]
+
+jobs:
+  github_release:
+    name: Trigger GitHub release
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout the new tag
+        uses: actions/checkout@v1.0.0
+
+      - name: Get tag info
+        id: tags
+        uses: babel/actions/get-release-tags@v2
+
+      - name: Generate the changelog
+        id: changelog
+        uses: babel/actions/generate-lerna-changelog@v2
+        with:
+          from: ${{ steps.tags.outputs.old }}
+          to: ${{ steps.tags.outputs.new }}
+        env:
+          GITHUB_AUTH: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Create a draft GitHub release
+        uses: babel/actions/publish-github-release@v2
+        with:
+          tag: ${{ steps.tags.outputs.new }}
+          changelog: ${{ steps.changelog.outputs.changelog }}
+          token: ${{ secrets.BOT_TOKEN }}
+
+      - name: Check if releasing from master
+        id: is_master
+        uses: babel/actions/ref-matches-branch@v2
+        with:
+          name: master
+
+      - name: Update CHANGELOG.md
+        if: steps.is_master.outputs.result == 1
+        uses: babel/actions/update-changelog@v2
+        with:
+          changelog: ${{ steps.changelog.outputs.changelog }}
+
+      - name: Commit CHANGELOG.md
+        if: steps.is_master.outputs.result == 1
+        run: |
+          git add CHANGELOG.md
+          git -c user.name="Babel Bot" -c user.email="babel-bot@users.noreply.github.com" \
+            commit -m "Add ${{ steps.tags.outputs.new }} to CHANGELOG.md [skip ci]" --no-verify --quiet
+          git push "https://babel-bot:${{ secrets.BOT_TOKEN }}@github.com/${GITHUB_REPOSITORY}.git" master

.travis.yml

@@ -3,41 +3,43 @@ git:
 language: node_js
 cache:
   yarn: true
-node_js:
-  # We test the latest version on circleci
-  - '11'
-  - '10'
-  - '8'
-  - '6'
+
+os: linux
 
 env:
   global:
     - PATH=$HOME/.yarn/bin:$PATH
     - JOB=test
 
-before_install:
-  - curl -o- -L https://yarnpkg.com/install.sh | bash
-
-install:
-  # the `make test-ci` script runs this command already
-  - if [ "$JOB" != "test" ] && [ "$JOB" != "lint" ]; then yarn install; fi
-  - if [ "$JOB" = "lint" ]; then make bootstrap; fi
-
+install: skip
 before_script:
-  - if [ "$JOB" = "babel-parser-flow-tests" ]; then make bootstrap-flow; fi
-  - if [ "$JOB" = "babel-parser-test262-tests" ]; then make bootstrap-test262; fi
+  - curl -o- -L https://yarnpkg.com/install.sh | bash
+  - if [ "$TRAVIS_OS_NAME" = "windows" ]; then choco install make; fi
 
 script:
-  - if [ "$JOB" = "test" ]; then make test-ci; fi
-  - if [ "$JOB" = "lint" ]; then make lint && make flow; fi
-  - if [ "$JOB" = "babel-parser-flow-tests" ]; then make test-flow-ci; fi
-  - if [ "$JOB" = "babel-parser-test262-tests" ]; then make test-test262-ci; fi
+  - if [ "$JOB" = "test" ]; then make -j test-ci; fi
+  - if [ "$JOB" = "lint" ]; then make -j code-quality-ci; fi
+  - if [ "$JOB" = "babel-parser-flow-tests" ]; then make -j test-flow-ci; fi
+  - if [ "$JOB" = "babel-parser-test262-tests" ]; then make -j test-test262-ci; fi
 
 matrix:
   fast_finish: true
   include:
     - node_js: "node"
       env: JOB=lint
+  # We test the latest version on circleci
+    - node_js: "11"
+  # Move `windows` build to be the third since it is slow
+    - os: windows
+      node_js: "node"
+      env:
+      - JOB=test
+      # https://travis-ci.community/t/build-doesnt-finish-after-completing-tests/288/9
+      - YARN_GPG=no
+  # Continue node_js matrix
+    - node_js: "6"
+    - node_js: "10"
+    - node_js: "8"
     - node_js: "node"
       env: JOB=babel-parser-flow-tests
     - node_js: "node"

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 > **Tags:**
 > - :boom:       [Breaking Change]
-> - :eyeglasses: [Spec Compliancy]
+> - :eyeglasses: [Spec Compliance]
 > - :rocket:     [New Feature]
 > - :bug:        [Bug Fix]
 > - :memo:       [Documentation]
@@ -17,6 +17,182 @@ See [Babylon's CHANGELOG](packages/babylon/CHANGELOG.md) for the Babylon pre-7.0
 
 <!-- DO NOT CHANGE THESE COMMENTS - See .github/actions/trigger-github-release/update-changelog.js -->
 <!-- insert-new-changelog-here -->
+## v7.6.3 (2019-10-08)
+
+#### :eyeglasses: Spec Compliance
+* `babel-parser`
+  * [#10469](https://github.com/babel/babel/pull/10469) Disallow await inside async arrow params ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+  * [#10493](https://github.com/babel/babel/pull/10493) [parser] Disallow numeric separators in legacy octal like integers ([@gonzarodriguezt](https://github.com/gonzarodriguezt))
+
+#### :rocket: New Feature
+* `babel-types`
+  * [#10504](https://github.com/babel/babel/pull/10504) Add declarations for more of @babel/types exports ([@Jessidhia](https://github.com/Jessidhia))
+
+#### :bug: Bug Fix
+* `babel-plugin-transform-block-scoping`
+  * [#10343](https://github.com/babel/babel/pull/10343) Do not remove let bindings even they are wrapped in closure ([@JLHwung](https://github.com/JLHwung))
+* `babel-parser`
+  * [#10119](https://github.com/babel/babel/pull/10119) add scope to TSModuleDeclaration ([@tanhauhau](https://github.com/tanhauhau))
+  * [#10332](https://github.com/babel/babel/pull/10332) Do not allow member expressions to start async arrows ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+  * [#10490](https://github.com/babel/babel/pull/10490) [parser] Don't crash on comment after trailing comma after elision ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+* `babel-plugin-transform-react-constant-elements`, `babel-traverse`
+  * [#10529](https://github.com/babel/babel/pull/10529) Do not hoist jsx referencing a mutable binding ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+* `babel-generator`, `babel-parser`, `babel-plugin-transform-block-scoping`, `babel-plugin-transform-flow-comments`, `babel-plugin-transform-flow-strip-types`, `babel-plugin-transform-typescript`
+  * [#10220](https://github.com/babel/babel/pull/10220) Flow: interface identifier should be declared in the scope ([@JLHwung](https://github.com/JLHwung))
+
+#### :nail_care: Polish
+* `babel-core`
+  * [#10419](https://github.com/babel/babel/pull/10419) assertNoDuplicates throw with more context ([@hjdivad](https://github.com/hjdivad))
+  * [#10511](https://github.com/babel/babel/pull/10511) Add filename to transform error ([@JLHwung](https://github.com/JLHwung))
+
+#### :house: Internal
+* Other
+  * [#10506](https://github.com/babel/babel/pull/10506) Use `make -j` for parallel build ([@JLHwung](https://github.com/JLHwung))
+  * [#10443](https://github.com/babel/babel/pull/10443) perf: only apply lazy cjs module transform on cli and core ([@JLHwung](https://github.com/JLHwung))
+  * [#10494](https://github.com/babel/babel/pull/10494) Enable optional chaining and nullish coalescing plugins ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+* `babel-cli`, `babel-core`, `babel-generator`, `babel-helper-fixtures`, `babel-helper-transform-fixture-test-runner`, `babel-node`, `babel-plugin-transform-react-jsx-source`, `babel-plugin-transform-runtime`, `babel-preset-env`, `babel-preset-react`
+  * [#10249](https://github.com/babel/babel/pull/10249) Add windows to travis ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+
+#### :running_woman: Performance
+* `babel-parser`
+  * [#10371](https://github.com/babel/babel/pull/10371) perf: replace lookahead by lookaheadCharCode ([@JLHwung](https://github.com/JLHwung))
+* Other
+  * [#10443](https://github.com/babel/babel/pull/10443) perf: only apply lazy cjs module transform on cli and core ([@JLHwung](https://github.com/JLHwung))
+## v7.6.2 (2019-09-23)
+
+#### :eyeglasses: Spec Compliance
+* `babel-parser`
+  * [#10472](https://github.com/babel/babel/pull/10472) added check to disallow super.private variable access and test case added. ([@vivek12345](https://github.com/vivek12345))
+  * [#10468](https://github.com/babel/babel/pull/10468) [parser] Disallow numeric separator in unicode scape sequences. ([@ivandevp](https://github.com/ivandevp))
+  * [#10467](https://github.com/babel/babel/pull/10467) [parser] Invalid NonOctal Decimal. ([@gonzarodriguezt](https://github.com/gonzarodriguezt))
+  * [#10461](https://github.com/babel/babel/pull/10461) [parser] Disallow static fields named `constructor`. ([@guywaldman](https://github.com/guywaldman))
+  * [#10455](https://github.com/babel/babel/pull/10455) [parser] Report escapes in kws only if they won't be used as identifiers. ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+
+#### :bug: Bug Fix
+* `babel-parser`
+  * [#10445](https://github.com/babel/babel/pull/10445) Leave trailing comments after handling a possible trailing comma. ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+* `babel-cli`
+  * [#10400](https://github.com/babel/babel/pull/10400) fix: allow the process to exit naturally. ([@JLHwung](https://github.com/JLHwung))
+* `babel-core`
+  * [#10402](https://github.com/babel/babel/pull/10402) fix: pass optionLoc when validating plugin object. ([@JLHwung](https://github.com/JLHwung))
+* `babel-plugin-transform-block-scoping`, `babel-plugin-transform-spread`, `babel-traverse`
+  * [#10417](https://github.com/babel/babel/pull/10417) Do not guess relative execution status for exported fns. ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+* `babel-plugin-proposal-object-rest-spread`, `babel-preset-env`
+  * [#10275](https://github.com/babel/babel/pull/10275) fix object rest in array pattern. ([@tanhauhau](https://github.com/tanhauhau))
+
+#### :house: Internal
+* `babel-plugin-transform-named-capturing-groups-regex`
+  * [#10430](https://github.com/babel/babel/pull/10430) refactor: replace regexp-tree by regexpu. ([@JLHwung](https://github.com/JLHwung))
+* Other
+  * [#10441](https://github.com/babel/babel/pull/10441) Update GitHub actions to v2. ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+  * [#10427](https://github.com/babel/babel/pull/10427) chore: add lint-ts rule. ([@JLHwung](https://github.com/JLHwung))
+* `babel-helper-fixtures`
+  * [#10428](https://github.com/babel/babel/pull/10428) chore: remove tryResolve dependency. ([@JLHwung](https://github.com/JLHwung))
+* `babel-node`
+  * [#10429](https://github.com/babel/babel/pull/10429) Remove babel polyfill dependency of babel-node. ([@bdwain](https://github.com/bdwain))
+* `babel-generator`, `babel-helper-fixtures`
+  * [#10420](https://github.com/babel/babel/pull/10420) chore: remove trim-right dependency. ([@JLHwung](https://github.com/JLHwung))
+* `babel-core`, `babel-plugin-transform-runtime`, `babel-register`
+  * [#10405](https://github.com/babel/babel/pull/10405) Remove circular dependency. ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+
+#### :running_woman: Performance
+* `babel-parser`
+  * [#10421](https://github.com/babel/babel/pull/10421) Miscellaneous perf tweak. ([@JLHwung](https://github.com/JLHwung))
+
+## v7.6.1 (2019-09-06)
+
+#### :bug: Bug Fix
+* `babel-types`
+  * [#10404](https://github.com/babel/babel/pull/10404) fix(types): correct typescript function headers ([@forstermatth](https://github.com/forstermatth))
+* `babel-node`
+  * [#9758](https://github.com/babel/babel/pull/9758) Remove process.exit(1) from babel-node ([@dword-design](https://github.com/dword-design))
+
+## v7.6.0 (2019-09-06)
+
+#### :eyeglasses: Spec Compliance
+* `babel-generator`, `babel-parser`
+  * [#10269](https://github.com/babel/babel/pull/10269) Fix parenthesis for nullish coalescing ([@vivek12345](https://github.com/vivek12345))
+* `babel-helpers`, `babel-plugin-transform-block-scoping`, `babel-traverse`
+  * [#9498](https://github.com/babel/babel/pull/9498) Fix tdz checks in transform-block-scoping plugin ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+
+#### :rocket: New Feature
+* `babel-core`
+  * [#10181](https://github.com/babel/babel/pull/10181) feat(errors): validate preset when filename is absent ([@JLHwung](https://github.com/JLHwung))
+* `babel-helper-create-class-features-plugin`, `babel-helpers`, `babel-plugin-proposal-private-methods`
+  * [#10217](https://github.com/babel/babel/pull/10217) Class Private Static Accessors ([@tim-mc](https://github.com/tim-mc))
+* `babel-generator`, `babel-parser`, `babel-types`
+  * [#10148](https://github.com/babel/babel/pull/10148) V8intrinsic syntax plugin ([@JLHwung](https://github.com/JLHwung))
+* `babel-preset-typescript`
+  * [#10382](https://github.com/babel/babel/pull/10382) Allow setting 'allowNamespaces' in typescript preset ([@dsgkirkby](https://github.com/dsgkirkby))
+* `babel-parser`
+  * [#10352](https://github.com/babel/babel/pull/10352) Do not register ambient classes to the TS scope ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+* `babel-types`
+  * [#10248](https://github.com/babel/babel/pull/10248) Add static to class property builder ([@yuri-karadzhov](https://github.com/yuri-karadzhov))
+
+#### :bug: Bug Fix
+* `babel-helpers`, `babel-plugin-transform-destructuring`, `babel-plugin-transform-modules-commonjs`, `babel-preset-env`
+  * [#10396](https://github.com/babel/babel/pull/10396) fix: early return when instance is not iterable ([@JLHwung](https://github.com/JLHwung))
+* `babel-plugin-transform-runtime`
+  * [#10398](https://github.com/babel/babel/pull/10398) Add supports for polyfill computed methods ([@rhyzx](https://github.com/rhyzx))
+* `babel-preset-env`
+  * [#10397](https://github.com/babel/babel/pull/10397) Don't polyfill when evaluation is not confident ([@rhyzx](https://github.com/rhyzx))
+  * [#10218](https://github.com/babel/babel/pull/10218) [preset-env] Include / exclude module plugins properly ([@AdamRamberg](https://github.com/AdamRamberg))
+  * [#10284](https://github.com/babel/babel/pull/10284) Replace es.string.reverse with es.array.reverse ([@epicfaace](https://github.com/epicfaace))
+* `babel-plugin-transform-named-capturing-groups-regex`
+  * [#10395](https://github.com/babel/babel/pull/10395) fix: transform name capturing regex once ([@JLHwung](https://github.com/JLHwung))
+* `babel-types`
+  * [#10098](https://github.com/babel/babel/pull/10098) fix typescript for babel-types ([@tanhauhau](https://github.com/tanhauhau))
+  * [#10319](https://github.com/babel/babel/pull/10319) Add a builder definition including name for tsTypeParameter ([@deificx](https://github.com/deificx))
+* `babel-parser`
+  * [#10380](https://github.com/babel/babel/pull/10380) Refactor trailing comment adjustment ([@banga](https://github.com/banga))
+  * [#10369](https://github.com/babel/babel/pull/10369) Retain trailing comments in array expressions ([@banga](https://github.com/banga))
+  * [#10292](https://github.com/babel/babel/pull/10292) fix: assign trailing comment to ObjectProperty only when inside an ObjectExpression ([@JLHwung](https://github.com/JLHwung))
+* `babel-parser`, `babel-types`
+  * [#10366](https://github.com/babel/babel/pull/10366) Don't allow JSXNamespacedName to chain ([@jridgewell](https://github.com/jridgewell))
+* `babel-generator`, `babel-plugin-transform-typescript`, `babel-types`
+  * [#10341](https://github.com/babel/babel/pull/10341) Add TSBigIntKeyword to @babel/types ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+* `babel-core`, `babel-types`
+  * [#9960](https://github.com/babel/babel/pull/9960) Do not delete "fake" source map comments from strings ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+* `babel-plugin-transform-flow-comments`
+  * [#10329](https://github.com/babel/babel/pull/10329) Fix flow comments plugin issues ([@zaygraveyard](https://github.com/zaygraveyard))
+* `babel-helpers`, `babel-plugin-transform-react-constant-elements`
+  * [#10307](https://github.com/babel/babel/pull/10307) [fix] jsx helper calls order ([@Sinewyk](https://github.com/Sinewyk))
+* `babel-plugin-proposal-decorators`
+  * [#10302](https://github.com/babel/babel/pull/10302) fix: register inserted class declaration ([@thiagoarrais](https://github.com/thiagoarrais))
+* `babel-plugin-proposal-do-expressions`, `babel-traverse`
+  * [#10070](https://github.com/babel/babel/pull/10070) Do expressions transform for switch statements ([@tanhauhau](https://github.com/tanhauhau))
+  * [#10277](https://github.com/babel/babel/pull/10277) remove finally from completion record in try statement ([@tanhauhau](https://github.com/tanhauhau))
+* `babel-helpers`, `babel-plugin-transform-named-capturing-groups-regex`
+  * [#10136](https://github.com/babel/babel/pull/10136) fix capturing group for matchAll ([@tanhauhau](https://github.com/tanhauhau))
+
+#### :nail_care: Polish
+* `babel-plugin-transform-runtime`, `babel-preset-env`
+  * [#10372](https://github.com/babel/babel/pull/10372) Don't allow instance properties transformation on namespace ([@rhyzx](https://github.com/rhyzx))
+
+#### :memo: Documentation
+* [#10313](https://github.com/babel/babel/pull/10313) Adds note about two approval policy to PR template ([@thiagoarrais](https://github.com/thiagoarrais))
+
+#### :house: Internal
+* `babel-register`
+  * [#9847](https://github.com/babel/babel/pull/9847) Remove core-js dependency from @babel/register ([@coreyfarrell](https://github.com/coreyfarrell))
+* `babel-helper-fixtures`, `babel-helper-transform-fixture-test-runner`, `babel-preset-env`
+  * [#10401](https://github.com/babel/babel/pull/10401) Use "validateLogs" for preset-env's debug fixtures ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+* `babel-parser`
+  * [#10380](https://github.com/babel/babel/pull/10380) Refactor trailing comment adjustment ([@banga](https://github.com/banga))
+* `babel-helper-fixtures`, `babel-helper-transform-fixture-test-runner`, `babel-plugin-proposal-dynamic-import`, `babel-preset-env`
+  * [#10326](https://github.com/babel/babel/pull/10326) Allow testing logs with `@babel/helper-transform-fixture-test-runner` ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
+* `babel-runtime-corejs2`, `babel-runtime`, `babel-types`
+  * [#10331](https://github.com/babel/babel/pull/10331) Commit generated code ([@JLHwung](https://github.com/JLHwung))
+* `babel-cli`, `babel-core`, `babel-generator`, `babel-helper-create-class-features-plugin`, `babel-helper-fixtures`, `babel-node`, `babel-parser`, `babel-plugin-proposal-do-expressions`, `babel-plugin-proposal-pipeline-operator`, `babel-plugin-transform-modules-commonjs`, `babel-plugin-transform-runtime`, `babel-preset-env`, `babel-standalone`, `babel-template`, `babel-traverse`, `babel-types`
+  * [#10228](https://github.com/babel/babel/pull/10228) Update dev dependencies and fix linting errors ([@danez](https://github.com/danez))
+* `babel-cli`
+  * [#10244](https://github.com/babel/babel/pull/10244) added flow to babel cli ([@Letladi](https://github.com/Letladi))
+
+#### :running_woman: Performance
+* `babel-helpers`, `babel-plugin-transform-modules-commonjs`, `babel-preset-env`
+  * [#10161](https://github.com/babel/babel/pull/10161) Improves the logic to import objects in helpers ([@ifsnow](https://github.com/ifsnow))
+* `babel-traverse`
+  * [#10243](https://github.com/babel/babel/pull/10243) perf: always return `void 0` as undefined node ([@JLHwung](https://github.com/JLHwung))
 
 ## v7.5.5 (2019-07-17)
 
@@ -389,7 +565,7 @@ See [Babylon's CHANGELOG](packages/babylon/CHANGELOG.md) for the Babylon pre-7.0
 
 ## v7.3.3 (2019-02-15)
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-generator`
   * [#9501](https://github.com/babel/babel/pull/9501) Correctly output escapes in directives ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
 
@@ -411,11 +587,11 @@ See [Babylon's CHANGELOG](packages/babylon/CHANGELOG.md) for the Babylon pre-7.0
   * [#9491](https://github.com/babel/babel/pull/9491) Better error output in parser tests ([@danez](https://github.com/danez))
 ## v7.3.2 (2019-02-04)
 
-Various spec compliancy fixes and better support for smart pipelines and private methods.
+Various spec compliance fixes and better support for smart pipelines and private methods.
 
 Thanks @gverni, @naffiq, @spondbob and @dstaley for their first PRs!
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-parser`
   * [#9403](https://github.com/babel/babel/pull/9403) Fix line continuation with Unicode line terminators. ([@danez](https://github.com/danez))
   * [#9400](https://github.com/babel/babel/pull/9400) Make yield a contextual keyword. ([@danez](https://github.com/danez))
@@ -463,7 +639,7 @@ This release fixes some regressions introduced in v7.3.0
 
 Thanks to @jamesgeorge007 and @armano2 for their first PR!
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-parser`
   * [#9314](https://github.com/babel/babel/pull/9314) Disallow async functions as loop body. ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
   * [#9315](https://github.com/babel/babel/pull/9315) Parse class heritage as strict mode code. ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
@@ -684,7 +860,7 @@ You can read more about this release at https://babeljs.io/blog/2018/12/03/7.2.0
 
 ## v7.1.5 (2018-11-06)
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-parser`, `babylon`
   * [#7727](https://github.com/babel/babel/pull/7727) Fix await in function name and parameters. ([@nicolo-ribaudo](https://github.com/nicolo-ribaudo))
 
@@ -1147,7 +1323,7 @@ Fixed a peerDep issue
 
 Mostly bug fixes and some decorator updates
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-plugin-proposal-unicode-property-regex`
   * [#8127](https://github.com/babel/babel/pull/8127) Update plugin-proposal-unicode-property-regex for Unicode v11. ([@mathiasbynens](https://github.com/mathiasbynens))
 * `babel-parser`
@@ -1247,7 +1423,7 @@ Mostly bugfix release for a regression in decorators, and a quick fix for some n
 - Fix IE10 class regression
 - Various fixes, many TS fixes
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-parser`, `babel-plugin-proposal-json-strings`, `babel-plugin-syntax-json-strings`, `babel-preset-stage-3`
   * [#7985](https://github.com/babel/babel/pull/7985) Subsume json. ([@jridgewell](https://github.com/jridgewell))
 
@@ -1437,7 +1613,7 @@ Mostly bugfix release for a regression in decorators, and a quick fix for some n
 * `babel-generator`, `babel-helper-define-map`, `babel-plugin-syntax-class-properties`, `babel-plugin-transform-parameters`, `babel-plugin-transform-react-constant-elements`, `babel-traverse`, `babel-types`
   * [#7666](https://github.com/babel/babel/pull/7666) Private Properties phase 1. ([@jridgewell](https://github.com/jridgewell))
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-helper-simple-access`, `babel-plugin-transform-modules-commonjs`, `babel-plugin-transform-modules-systemjs`
   * [#7766](https://github.com/babel/babel/pull/7766) Correct update expression Number coercion. ([@jridgewell](https://github.com/jridgewell))
 * `babel-core`, `babel-generator`, `babel-plugin-proposal-decorators`, `babel-types`, `babylon`
@@ -1525,7 +1701,7 @@ Mostly bugfix release for a regression in decorators, and a quick fix for some n
 
 Various fixes, also lazy-load `@babel/core` dependencies (should make config lookup and other API methods fast for other projects to use).
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-plugin-proposal-logical-assignment-operators`
   * [#7604](https://github.com/babel/babel/pull/7604) Logical Assignment: ensure computed key isn't recomputed. ([@jridgewell](https://github.com/jridgewell))
 
@@ -1624,7 +1800,7 @@ We'll need to update tooling for this ^. Also published `gulp-babel@8.0.0-beta.2
 * `babel-register`
   * [#7416](https://github.com/babel/babel/pull/7416) Replace instead of merging babel-register options, and resolve cwd up front. ([@loganfsmyth](https://github.com/loganfsmyth))
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babylon`
   * [#7503](https://github.com/babel/babel/pull/7503) Update test262 test script and a few keyword escape fixes. ([@existentialism](https://github.com/existentialism))
   * [#7498](https://github.com/babel/babel/pull/7498) Disallow setters to have RestElement. ([@danez](https://github.com/danez))
@@ -1772,7 +1948,7 @@ We'll need to update tooling for this ^. Also published `gulp-babel@8.0.0-beta.2
 
 ## v7.0.0-beta.39 (2018-01-30)
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-plugin-proposal-optional-chaining`
   * [#6345](https://github.com/babel/babel/pull/6345) Remove old optional chain features. ([@jridgewell](https://github.com/jridgewell))
 
@@ -1985,7 +2161,7 @@ Fixes + [overrides](https://github.com/babel/babel/pull/7091) config feature
 
 Various bug fixes, first version of Babel to use the MIT version of `regenerator`
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babylon`
   * [#6986](https://github.com/babel/babel/pull/6986) Fix destructuring assignment spec violation. ([@ksashikumar](https://github.com/ksashikumar))
 * `babel-helper-replace-supers`, `babel-helpers`, `babel-plugin-proposal-class-properties`, `babel-plugin-transform-classes`, `babel-plugin-transform-parameters`
@@ -2038,7 +2214,7 @@ Various bug fixes, first version of Babel to use the MIT version of `regenerator
 * `babel-preset-stage-1`, `babel-preset-stage-2`
   * [#6949](https://github.com/babel/babel/pull/6949) Fix stage refs to exportNamespaceFrom and exportDefaultFrom. ([@existentialism](https://github.com/existentialism))
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-preset-stage-0`, `babel-preset-stage-1`
   * [#6943](https://github.com/babel/babel/pull/6943) Moving Do expression to stage 1. ([@rajzshkr](https://github.com/rajzshkr))
 
@@ -2052,7 +2228,7 @@ Various bug fixes, first version of Babel to use the MIT version of `regenerator
 
 ## v7.0.0-beta.33 (2017-12-01)
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-generator`, `babel-plugin-proposal-export-default-from`, `babel-plugin-proposal-export-default`, `babel-plugin-proposal-export-namespace-from`, `babel-plugin-proposal-export-namespace`, `babel-plugin-syntax-export-default-from`, `babel-plugin-syntax-export-extensions`, `babel-plugin-syntax-export-namespace-from`, `babel-standalone`, `babylon`
   * [#6920](https://github.com/babel/babel/pull/6920) Split exportExtensions into exportDefault and exportNamespace plugins…. ([@existentialism](https://github.com/existentialism))
 * `babylon`
@@ -2237,7 +2413,7 @@ Various bug fixes, first version of Babel to use the MIT version of `regenerator
 
 > Note: don't use ^ in your dependencies when using a beta. It can still break between (we should try not to do it but it can), so pin all the packages like `"@babel/cli" : "7.0.0-beta.4"`
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-plugin-transform-optional-chaining`
   * [#6525](https://github.com/babel/babel/pull/6525) Optional Chaining: Account for document.all. ([@azz](https://github.com/azz))
 * `babel-preset-env`, `babel-helper-remap-async-to-generator`, `babel-helpers`, `babel-plugin-transform-async-generator-functions`, `babel-plugin-transform-async-to-generator`, `babel-plugin-transform-function-sent`
@@ -2517,7 +2693,7 @@ let {...{}} = {}; let {...[]} = {};
 - Add `--config-file` CLI flag to explicitly pass a config location
 - Move `babel-standalone` into the repo (another form of this used to be `babel-browser`)
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-plugin-transform-async-to-generator`, `babel-*`
   * [#6094](https://github.com/babel/babel/pull/6094) Spec compatibility for iteratorClose condition.. ([@yavorsky](https://github.com/yavorsky))
 * `babel-helpers`, `babel-plugin-transform-es2015-computed-properties`
@@ -2653,7 +2829,7 @@ Initial release of typescript equivalent of how Babel handles flow with a new `b
 
 ## v7.0.0-alpha.18 (2017-08-03)
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-generator`, `babel-plugin-transform-flow-comments`, `babel-plugin-transform-flow-strip-types`, `babel-types`
   * [#5990](https://github.com/babel/babel/pull/5990) Flow opaque type aliases. ([@jbrown215](https://github.com/jbrown215))
 * `babel-preset-stage-3`
@@ -2702,9 +2878,9 @@ Initial release of typescript equivalent of how Babel handles flow with a new `b
 - Optional catch binding `try {} catch {}`: `babel-plugin-transform-optional-catch-binding`
 - es2015-parameters `loose` mode that doesn't use `arguments`
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-plugin-check-es2015-constants`
-  * [#5930](https://github.com/babel/babel/pull/5930) Spec compliancy of check-es2015-constants plugin. ([@maurobringolf](https://github.com/maurobringolf))
+  * [#5930](https://github.com/babel/babel/pull/5930) Spec compliance of check-es2015-constants plugin. ([@maurobringolf](https://github.com/maurobringolf))
 
 > Instead of throwing a compile time error when const is violated, Babel should insert a throw statement before the violation.
 
@@ -3009,7 +3185,7 @@ var A = function A() {
 
 ## v7.0.0-alpha.12 (2017-05-31)
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-core`, `babel-generator`, `babel-plugin-syntax-numeric-separator`, `babel-plugin-transform-numeric-separator`, `babel-preset-stage-1`, `babel-template`, `babel-traverse`, `babel-types`
   * [#5793](https://github.com/babel/babel/pull/5793) Support for NumericLiteralSeparator, Stage 1 feature. ([@rwaldron](https://github.com/rwaldron))
 
@@ -3050,7 +3226,7 @@ var A = function A() {
 
 Update Babylon: https://github.com/babel/babylon/releases/tag/v7.0.0-beta.9, https://github.com/babel/babylon/releases/tag/v7.0.0-beta.10
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-generator`, `babel-plugin-transform-flow-strip-types`, `babel-types`
   * [#5525](https://github.com/babel/babel/pull/5525) Add support for object type spread. ([@conartist6](https://github.com/conartist6))
 
@@ -3124,7 +3300,7 @@ Update Babylon: https://github.com/babel/babylon/releases/tag/v7.0.0-beta.9, htt
 
 ## v7.0.0-alpha.8 (2017-04-17)
 
-#### :eyeglasses: Spec Compliancy
+#### :eyeglasses: Spec Compliance
 * `babel-preset-stage-2`, `babel-preset-stage-3`
   * [#5610](https://github.com/babel/babel/pull/5610) Move syntax-dynamic-import to stage-3. ([@dkaoster](https://github.com/dkaoster))
 

Gulpfile.js

@@ -11,25 +11,20 @@ const filter = require("gulp-filter");
 const gulp = require("gulp");
 const path = require("path");
 const webpack = require("webpack");
-const merge = require("merge-stream");
 const rollup = require("rollup");
 const rollupBabel = require("rollup-plugin-babel");
 const rollupNodeResolve = require("rollup-plugin-node-resolve");
 const rollupReplace = require("rollup-plugin-replace");
 const { registerStandalonePackageTask } = require("./scripts/gulp-tasks");
 
-const sources = ["codemods", "packages"];
+const defaultSourcesGlob = "./@(codemods|packages)/*/src/**/*.js";
 
 function swapSrcWithLib(srcPath) {
   const parts = srcPath.split(path.sep);
-  parts[1] = "lib";
+  parts[2] = "lib";
   return parts.join(path.sep);
 }
 
-function getGlobFromSource(source) {
-  return `./${source}/*/src/**/*.js`;
-}
-
 function getIndexFromPackage(name) {
   return `${name}/src/index.js`;
 }
@@ -56,32 +51,28 @@ function rename(fn) {
   });
 }
 
-function buildBabel(exclude) {
-  return merge(
-    sources.map(source => {
-      const base = path.join(__dirname, source);
+function buildBabel(exclude, sourcesGlob = defaultSourcesGlob) {
+  const base = __dirname;
 
-      let stream = gulp.src(getGlobFromSource(source), { base: base });
+  let stream = gulp.src(sourcesGlob, { base: __dirname });
 
-      if (exclude) {
-        const filters = exclude.map(p => `!**/${p}/**`);
-        filters.unshift("**");
-        stream = stream.pipe(filter(filters));
-      }
+  if (exclude) {
+    const filters = exclude.map(p => `!**/${p}/**`);
+    filters.unshift("**");
+    stream = stream.pipe(filter(filters));
+  }
 
-      return stream
-        .pipe(errorsLogger())
-        .pipe(newer({ dest: base, map: swapSrcWithLib }))
-        .pipe(compilationLogger())
-        .pipe(babel())
-        .pipe(
-          // Passing 'file.relative' because newer() above uses a relative
-          // path and this keeps it consistent.
-          rename(file => path.resolve(file.base, swapSrcWithLib(file.relative)))
-        )
-        .pipe(gulp.dest(base));
-    })
-  );
+  return stream
+    .pipe(errorsLogger())
+    .pipe(newer({ dest: base, map: swapSrcWithLib }))
+    .pipe(compilationLogger())
+    .pipe(babel())
+    .pipe(
+      // Passing 'file.relative' because newer() above uses a relative
+      // path and this keeps it consistent.
+      rename(file => path.resolve(file.base, swapSrcWithLib(file.relative)))
+    )
+    .pipe(gulp.dest(base));
 }
 
 function buildRollup(packages) {
@@ -118,6 +109,9 @@ const bundles = ["packages/babel-parser"];
 
 gulp.task("build-rollup", () => buildRollup(bundles));
 gulp.task("build-babel", () => buildBabel(/* exclude */ bundles));
+gulp.task("build-babel-types", () =>
+  buildBabel(/* exclude */ bundles, "packages/babel-types/src/**/*.js")
+);
 gulp.task("build", gulp.parallel("build-rollup", "build-babel"));
 
 gulp.task("default", gulp.series("build"));
@@ -128,7 +122,7 @@ gulp.task(
   "watch",
   gulp.series("build-no-bundle", function watch() {
     gulpWatch(
-      sources.map(getGlobFromSource),
+      defaultSourcesGlob,
       { debounceDelay: 200 },
       gulp.task("build-no-bundle")
     );

Makefile

@@ -1,6 +1,5 @@
-MAKEFLAGS = -j1
 FLOW_COMMIT = 09669846b7a7ca5a6c23c12d56bb3bebdafd67e9
-TEST262_COMMIT = de567d3aa5de4eaa11e00131d26b9fe77997dfb0
+TEST262_COMMIT = 8688c4ab79059c3097098605e69f1ee5eda6c409
 
 # Fix color output until TravisCI fixes https://github.com/travis-ci/travis-ci/issues/7967
 export FORCE_COLOR = true
@@ -9,59 +8,110 @@ SOURCES = packages codemods
 
 .PHONY: build build-dist watch lint fix clean test-clean test-only test test-ci publish bootstrap
 
-build: clean clean-lib
-	./node_modules/.bin/gulp build
-	node ./packages/babel-standalone/scripts/generate.js
-	node ./packages/babel-types/scripts/generateTypeHelpers.js
-	# call build again as the generated files might need to be compiled again.
-	./node_modules/.bin/gulp build
-	# generate flow and typescript typings
-	node packages/babel-types/scripts/generators/flow.js > ./packages/babel-types/lib/index.js.flow
-	node packages/babel-types/scripts/generators/typescript.js > ./packages/babel-types/lib/index.d.ts
+build: build-bundle
 ifneq ("$(BABEL_COVERAGE)", "true")
-	make build-standalone
-	make build-preset-env-standalone
+	$(MAKE) build-standalone
 endif
 
-build-standalone:
-	./node_modules/.bin/gulp build-babel-standalone
+build-bundle: clean clean-lib
+	yarn gulp build
+	$(MAKE) generate-standalone generate-type-helpers
+	# call build again as the generated files might need to be compiled again.
+	yarn gulp build
+	$(MAKE) build-typings
+	$(MAKE) build-dist
+
+build-bundle-ci: bootstrap-only
+	$(MAKE) build-bundle
+
+generate-standalone:
+	node packages/babel-standalone/scripts/generate.js
+
+generate-type-helpers:
+	node packages/babel-types/scripts/generateTypeHelpers.js
+
+build-typings: build-flow-typings build-typescript-typings
+
+build-flow-typings:
+	node packages/babel-types/scripts/generators/flow.js > packages/babel-types/lib/index.js.flow
+
+build-typescript-typings:
+	node packages/babel-types/scripts/generators/typescript.js > packages/babel-types/lib/index.d.ts
+
+build-standalone: build-babel-standalone build-preset-env-standalone
+
+build-standalone-ci: build-bundle-ci
+	$(MAKE) build-standalone
+
+build-babel-standalone:
+	yarn gulp build-babel-standalone
 
 build-preset-env-standalone:
-	./node_modules/.bin/gulp build-babel-preset-env-standalone
+	yarn gulp build-babel-preset-env-standalone
 
 prepublish-build-standalone:
-	BABEL_ENV=production IS_PUBLISH=true ./node_modules/.bin/gulp build-babel-standalone
+	BABEL_ENV=production IS_PUBLISH=true yarn gulp build-babel-standalone
 
 prepublish-build-preset-env-standalone:
-	BABEL_ENV=production IS_PUBLISH=true ./node_modules/.bin/gulp build-babel-preset-env-standalone
+	BABEL_ENV=production IS_PUBLISH=true yarn gulp build-babel-preset-env-standalone
 
-build-dist: build
+build-dist: build-polyfill-dist build-plugin-transform-runtime-dist
+
+build-polyfill-dist:
 	cd packages/babel-polyfill; \
 	scripts/build-dist.sh
+
+build-plugin-transform-runtime-dist:
 	cd packages/babel-plugin-transform-runtime; \
 	node scripts/build-dist.js
 
-watch: clean clean-lib
-
+build-no-bundle: clean clean-lib
+	BABEL_ENV=development yarn gulp build-no-bundle
 	# Ensure that build artifacts for types are created during local
 	# development too.
-	BABEL_ENV=development ./node_modules/.bin/gulp build-no-bundle
-	node ./packages/babel-types/scripts/generateTypeHelpers.js
-	node packages/babel-types/scripts/generators/flow.js > ./packages/babel-types/lib/index.js.flow
-	node packages/babel-types/scripts/generators/typescript.js > ./packages/babel-types/lib/index.d.ts
-	BABEL_ENV=development ./node_modules/.bin/gulp watch
+	$(MAKE) generate-type-helpers
+	$(MAKE) build-typings
+
+watch: build-no-bundle
+	BABEL_ENV=development yarn gulp watch
+
+code-quality-ci: flowcheck-ci lint-ci
+
+flowcheck-ci: bootstrap-flowcheck
+	$(MAKE) flow
+
+code-quality: flow lint
 
 flow:
-	./node_modules/.bin/flow check --strip-root
+	yarn flow check --strip-root
 
-lint:
-	./node_modules/.bin/eslint scripts $(SOURCES) '*.js' --format=codeframe
+bootstrap-flowcheck: bootstrap-only
+	yarn gulp build-babel-types
+	$(MAKE) build-typings
 
-fix: fix-json
-	./node_modules/.bin/eslint scripts $(SOURCES) '*.js' --format=codeframe --fix
+lint-ci: lint-js-ci lint-ts-ci
+
+lint-js-ci: bootstrap-only
+	$(MAKE) lint-js
+
+lint-ts-ci: bootstrap-flowcheck
+	$(MAKE) lint-ts
+
+lint: lint-js lint-ts
+
+lint-js:
+	yarn eslint scripts $(SOURCES) '*.js' --format=codeframe
+
+lint-ts:
+	scripts/tests/typescript/lint.sh
+
+fix: fix-json fix-js
+
+fix-js:
+	yarn eslint scripts $(SOURCES) '*.js' --format=codeframe --fix
 
 fix-json:
-	./node_modules/.bin/prettier "{packages,codemod}/*/test/fixtures/**/options.json" --write --loglevel warn
+	yarn prettier "{packages,codemod}/*/test/fixtures/**/options.json" --write --loglevel warn
 
 clean: test-clean
 	rm -f .npmrc
@@ -74,72 +124,77 @@ test-clean:
 	$(foreach source, $(SOURCES), \
 		$(call clean-source-test, $(source)))
 
+# Does not work on Windows; use "yarn jest" instead
 test-only:
 	BABEL_ENV=test ./scripts/test.sh
-	make test-clean
+	$(MAKE) test-clean
 
 test: lint test-only
 
-test-ci: bootstrap test-only
+test-ci: jest-ci
 
+jest-ci: build-standalone-ci
+	BABEL_ENV=test yarn jest --maxWorkers=4 --ci
+	$(MAKE) test-clean
+
+# Does not work on Windows
 test-ci-coverage: SHELL:=/bin/bash
 test-ci-coverage:
-	BABEL_COVERAGE=true BABEL_ENV=test make bootstrap
+	BABEL_COVERAGE=true BABEL_ENV=test $(MAKE) bootstrap
 	BABEL_ENV=test TEST_TYPE=cov ./scripts/test-cov.sh
 	bash <(curl -s https://codecov.io/bash) -f coverage/coverage-final.json
 
 bootstrap-flow:
-	rm -rf ./build/flow
-	mkdir -p ./build
-	git clone --branch=master --single-branch --shallow-since=2018-11-01 https://github.com/facebook/flow.git ./build/flow
+	rm -rf build/flow
+	mkdir -p build
+	git clone --branch=master --single-branch --shallow-since=2018-11-01 https://github.com/facebook/flow.git build/flow
 	cd build/flow && git checkout $(FLOW_COMMIT)
 
 test-flow:
 	node scripts/tests/flow/run_babel_parser_flow_tests.js
 
-test-flow-ci: bootstrap test-flow
+test-flow-ci: build-bundle-ci bootstrap-flow
+	$(MAKE) test-flow
 
 test-flow-update-whitelist:
 	node scripts/tests/flow/run_babel_parser_flow_tests.js --update-whitelist
 
 bootstrap-test262:
-	rm -rf ./build/test262
-	mkdir -p ./build
-	git clone --branch=master --single-branch --shallow-since=2019-01-01 https://github.com/tc39/test262.git ./build/test262
+	rm -rf build/test262
+	mkdir -p build
+	git clone --branch=master --single-branch --shallow-since=2019-09-01 https://github.com/tc39/test262.git build/test262
 	cd build/test262 && git checkout $(TEST262_COMMIT)
 
 test-test262:
 	node scripts/tests/test262/run_babel_parser_test262.js
 
-test-test262-ci: bootstrap test-test262
+test-test262-ci: build-bundle-ci bootstrap-test262
+	$(MAKE) test-test262
 
 test-test262-update-whitelist:
 	node scripts/tests/test262/run_babel_parser_test262.js --update-whitelist
 
+# Does not work on Windows
 clone-license:
 	./scripts/clone-license.sh
 
-prepublish-build:
-	make clean-lib
-	rm -rf packages/babel-runtime/helpers
-	rm -rf packages/babel-runtime-corejs2/helpers
-	rm -rf packages/babel-runtime-corejs2/core-js
-	NODE_ENV=production BABEL_ENV=production make build-dist
-	make clone-license
+prepublish-build: clean-lib clean-runtime-helpers
+	NODE_ENV=production BABEL_ENV=production $(MAKE) build
+	$(MAKE) clone-license
 
 prepublish:
-	make bootstrap-only
-	make prepublish-build
-	make test
+	$(MAKE) bootstrap-only
+	$(MAKE) prepublish-build
+	$(MAKE) test
 
 new-version:
 	git pull --rebase
-	./node_modules/.bin/lerna version --force-publish="@babel/runtime,@babel/runtime-corejs2,@babel/runtime-corejs3,@babel/standalone,@babel/preset-env-standalone"
+	yarn lerna version --force-publish="@babel/runtime,@babel/runtime-corejs2,@babel/runtime-corejs3,@babel/standalone,@babel/preset-env-standalone"
 
 # NOTE: Run make new-version first
 publish: prepublish
-	./node_modules/.bin/lerna publish from-git --require-scripts
-	make clean
+	yarn lerna publish from-git --require-scripts
+	$(MAKE) clean
 
 publish-ci: prepublish
 ifneq ("$(NPM_TOKEN)", "")
@@ -148,23 +203,30 @@ else
 	echo "Missing NPM_TOKEN env var"
 	exit 1
 endif
-	./node_modules/.bin/lerna publish from-git --require-scripts --yes
+	yarn lerna publish from-git --require-scripts --yes
 	rm -f .npmrc
-	make clean
+	$(MAKE) clean
 
-bootstrap-only: clean-all
+bootstrap-only: lerna-bootstrap
+
+yarn-install: clean-all
 	yarn --ignore-engines
-	./node_modules/.bin/lerna bootstrap -- --ignore-engines
+
+lerna-bootstrap: yarn-install
+	yarn lerna bootstrap -- --ignore-engines
 
 bootstrap: bootstrap-only
-	make build
-	cd packages/babel-plugin-transform-runtime; \
-	node scripts/build-dist.js
+	$(MAKE) build
 
 clean-lib:
 	$(foreach source, $(SOURCES), \
 		$(call clean-source-lib, $(source)))
 
+clean-runtime-helpers:
+	rm -rf packages/babel-runtime/helpers
+	rm -rf packages/babel-runtime-corejs2/helpers
+	rm -rf packages/babel-runtime-corejs2/core-js
+
 clean-all:
 	rm -rf node_modules
 	rm -rf package-lock.json
@@ -173,7 +235,7 @@ clean-all:
 	$(foreach source, $(SOURCES), \
 		$(call clean-source-all, $(source)))
 
-	make clean
+	$(MAKE) clean
 
 define clean-source-lib
 	rm -rf $(1)/*/lib

babel.config.js

@@ -77,9 +77,10 @@ module.exports = function(api) {
         "@babel/proposal-object-rest-spread",
         { useBuiltIns: true, loose: true },
       ],
+      "@babel/plugin-proposal-optional-chaining",
+      "@babel/plugin-proposal-nullish-coalescing-operator",
 
-      // Explicitly use the lazy version of CommonJS modules.
-      convertESM ? ["@babel/transform-modules-commonjs", { lazy: true }] : null,
+      convertESM ? "@babel/transform-modules-commonjs" : null,
     ].filter(Boolean),
     overrides: [
       {
@@ -90,18 +91,17 @@ module.exports = function(api) {
         ],
       },
       {
-        test: "./packages/babel-register",
+        test: ["./packages/babel-cli", "./packages/babel-core"],
         plugins: [
-          // Override the root options to disable lazy imports for babel-register
-          // because otherwise the require hook will try to lazy-import things
-          // leading to dependency cycles.
-          convertESM ? "@babel/transform-modules-commonjs" : null,
+          // Explicitly use the lazy version of CommonJS modules.
+          convertESM
+            ? ["@babel/transform-modules-commonjs", { lazy: true }]
+            : null,
         ].filter(Boolean),
       },
       {
         test: "./packages/babel-polyfill",
         presets: [["@babel/env", envOptsNoTargets]],
-        plugins: [["@babel/transform-modules-commonjs", { lazy: false }]],
       },
       {
         // The vast majority of our src files are modules, but we use

doc/design/monorepo.md

@@ -15,7 +15,7 @@ This is quite taboo but let's look at the pros and cons:
  * Easy to coordinate changes across modules.
  * Single place to report issues.
  * Easier to setup a development environment.
- * Tests across modules are run together which finds bugs that touch multiple modules easier.
+ * Tests across modules are run together which finds bugs that touch multiple modules more easily.
 
 **Cons:**
 

lerna.json

@@ -1,5 +1,5 @@
 {
-  "version": "7.6.0",
+  "version": "7.6.4",
   "changelog": {
     "repo": "babel/babel",
     "cacheDir": ".changelog",

package.json

@@ -9,20 +9,22 @@
     "test": "make test"
   },
   "devDependencies": {
-    "@babel/cli": "^7.4.4",
-    "@babel/core": "^7.4.5",
+    "@babel/cli": "^7.6.0",
+    "@babel/core": "^7.6.0",
     "@babel/eslint-plugin-development": "^1.0.1",
-    "@babel/plugin-proposal-class-properties": "^7.4.4",
-    "@babel/plugin-proposal-export-namespace-from": "^7.2.0",
+    "@babel/plugin-proposal-class-properties": "^7.5.5",
+    "@babel/plugin-proposal-export-namespace-from": "^7.5.2",
+    "@babel/plugin-proposal-nullish-coalescing-operator": "^7.4.4",
     "@babel/plugin-proposal-numeric-separator": "^7.2.0",
-    "@babel/plugin-transform-modules-commonjs": "^7.4.4",
-    "@babel/plugin-transform-runtime": "^7.4.4",
-    "@babel/preset-env": "^7.4.5",
+    "@babel/plugin-proposal-optional-chaining": "^7.6.0",
+    "@babel/plugin-transform-modules-commonjs": "^7.6.0",
+    "@babel/plugin-transform-runtime": "^7.6.0",
+    "@babel/preset-env": "^7.6.0",
     "@babel/preset-flow": "^7.0.0",
-    "@babel/register": "^7.4.4",
-    "@babel/runtime": "^7.4.5",
+    "@babel/register": "^7.6.0",
+    "@babel/runtime": "^7.6.0",
     "babel-eslint": "^11.0.0-beta.0",
-    "babel-jest": "^24.8.0",
+    "babel-jest": "^24.9.0",
     "babel-loader": "^8.0.6",
     "babel-plugin-transform-charcodes": "^0.2.0",
     "browserify": "^16.2.3",
@@ -38,7 +40,7 @@
     "eslint-plugin-import": "^2.17.2",
     "eslint-plugin-prettier": "^3.1.0",
     "fancy-log": "^1.3.3",
-    "flow-bin": "^0.102.0",
+    "flow-bin": "^0.108.0",
     "graceful-fs": "^4.1.15",
     "gulp": "^4.0.2",
     "gulp-babel": "^8.0.0",
@@ -49,12 +51,11 @@
     "gulp-uglify": "^3.0.2",
     "gulp-watch": "^5.0.1",
     "husky": "^3.0.0",
-    "jest": "^24.8.0",
+    "jest": "^24.9.0",
     "lerna": "^3.16.0",
     "lerna-changelog": "^0.5.0",
     "lint-staged": "^9.2.0",
     "lodash": "^4.17.13",
-    "merge-stream": "^1.0.1",
     "output-file-sync": "^2.0.0",
     "prettier": "^1.17.1",
     "pump": "^3.0.0",
@@ -63,8 +64,9 @@
     "rollup-plugin-babel": "^4.0.0",
     "rollup-plugin-node-resolve": "^5.0.0",
     "rollup-plugin-replace": "^2.2.0",
-    "test262-stream": "^1.2.0",
+    "test262-stream": "^1.3.0",
     "through2": "^2.0.0",
+    "typescript": "^3.6.3",
     "warnings-to-errors-webpack-plugin": "^2.0.0",
     "webpack": "^3.4.1",
     "webpack-dependency-suite": "^2.4.4",

packages/babel-cli/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/cli",
-  "version": "7.6.0",
+  "version": "7.6.4",
   "description": "Babel command line.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -36,8 +36,8 @@
     "@babel/core": "^7.0.0-0"
   },
   "devDependencies": {
-    "@babel/core": "^7.6.0",
-    "@babel/helper-fixtures": "^7.6.0"
+    "@babel/core": "^7.6.4",
+    "@babel/helper-fixtures": "^7.6.3"
   },
   "bin": {
     "babel": "./bin/babel.js",

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

@@ -6,8 +6,12 @@ import fileCommand from "./file";
 
 const opts = parseArgv(process.argv);
 
-const fn = opts.cliOptions.outDir ? dirCommand : fileCommand;
-fn(opts).catch(err => {
-  console.error(err);
-  process.exit(1);
-});
+if (opts) {
+  const fn = opts.cliOptions.outDir ? dirCommand : fileCommand;
+  fn(opts).catch(err => {
+    console.error(err);
+    process.exitCode = 1;
+  });
+} else {
+  process.exitCode = 2;
+}

packages/babel-cli/src/babel/options.js

@@ -158,7 +158,7 @@ export type CmdOptions = {
   cliOptions: Object,
 };
 
-export default function parseArgv(args: Array<string>): CmdOptions {
+export default function parseArgv(args: Array<string>): CmdOptions | null {
   //
   commander.parse(args);
 
@@ -223,7 +223,7 @@ export default function parseArgv(args: Array<string>): CmdOptions {
     errors.forEach(function(e) {
       console.error("  " + e);
     });
-    process.exit(2);
+    return null;
   }
 
   const opts = commander.opts();

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

@@ -112,7 +112,7 @@ export function deleteDir(path: string): void {
 
 process.on("uncaughtException", function(err) {
   console.error(err);
-  process.exit(1);
+  process.exitCode = 1;
 });
 
 export function requireChokidar(): Object {

packages/babel-cli/test/fixtures/babel/stdin --filename windows/options.json

@@ -0,0 +1,5 @@
+{
+  "args": ["--filename", "test.js"],
+  "stderrContains": true,
+  "os": ["win32"]
+}

packages/babel-cli/test/fixtures/babel/stdin --filename windows/stderr.txt

@@ -0,0 +1 @@
+SyntaxError: <CWD>\test.js: Unexpected token, expected ";" (2:10)

packages/babel-cli/test/fixtures/babel/stdin --filename windows/stdin.txt

@@ -0,0 +1,3 @@
+arr.map(function () {
+  return $]!;
+});

packages/babel-cli/test/fixtures/babel/stdin --filename/options.json

@@ -1,4 +1,5 @@
 {
   "args": ["--filename", "test.js"],
-  "stderrContains": true
+  "stderrContains": true,
+  "os": ["linux", "darwin"]
 }

packages/babel-cli/test/index.js

@@ -185,7 +185,29 @@ fs.readdirSync(fixtureLoc).forEach(function(binName) {
       };
 
       const optionsLoc = path.join(testLoc, "options.json");
-      if (fs.existsSync(optionsLoc)) merge(opts, require(optionsLoc));
+      if (fs.existsSync(optionsLoc)) {
+        const taskOpts = require(optionsLoc);
+        if (taskOpts.os) {
+          let os = taskOpts.os;
+
+          if (!Array.isArray(os) && typeof os !== "string") {
+            throw new Error(
+              `'os' should be either string or string array: ${taskOpts.os}`,
+            );
+          }
+
+          if (typeof os === "string") {
+            os = [os];
+          }
+
+          if (!os.includes(process.platform)) {
+            return;
+          }
+
+          delete taskOpts.os;
+        }
+        merge(opts, taskOpts);
+      }
 
       ["stdout", "stdin", "stderr"].forEach(function(key) {
         const loc = path.join(testLoc, key + ".txt");
@@ -205,7 +227,7 @@ fs.readdirSync(fixtureLoc).forEach(function(binName) {
         opts.inFiles[".babelrc"] = helper.readFile(babelrcLoc);
       }
 
-      it(testName, buildTest(binName, testName, opts));
+      it(testName, buildTest(binName, testName, opts), 20000);
     });
   });
 });

packages/babel-core/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/core",
-  "version": "7.6.0",
+  "version": "7.6.4",
   "description": "Babel compiler core.",
   "main": "lib/index.js",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
@@ -34,12 +34,12 @@
   },
   "dependencies": {
     "@babel/code-frame": "^7.5.5",
-    "@babel/generator": "^7.6.0",
-    "@babel/helpers": "^7.6.0",
-    "@babel/parser": "^7.6.0",
+    "@babel/generator": "^7.6.4",
+    "@babel/helpers": "^7.6.2",
+    "@babel/parser": "^7.6.4",
     "@babel/template": "^7.6.0",
-    "@babel/traverse": "^7.6.0",
-    "@babel/types": "^7.6.0",
+    "@babel/traverse": "^7.6.3",
+    "@babel/types": "^7.6.3",
     "convert-source-map": "^1.1.0",
     "debug": "^4.1.0",
     "json5": "^2.1.0",
@@ -49,7 +49,6 @@
     "source-map": "^0.5.0"
   },
   "devDependencies": {
-    "@babel/helper-transform-fixture-test-runner": "^7.6.0",
-    "@babel/register": "^7.6.0"
+    "@babel/helper-transform-fixture-test-runner": "^7.6.4"
   }
 }

packages/babel-core/src/config/config-descriptors.js

@@ -345,6 +345,7 @@ function assertNoDuplicates(items: Array<UnloadedDescriptor>): void {
     }
 
     if (nameMap.has(item.name)) {
+      const conflicts = items.filter(i => i.value === item.value);
       throw new Error(
         [
           `Duplicate plugin/preset detected.`,
@@ -355,6 +356,9 @@ function assertNoDuplicates(items: Array<UnloadedDescriptor>): void {
           `    ['some-plugin', {}],`,
           `    ['some-plugin', {}, 'some unique name'],`,
           `  ]`,
+          ``,
+          `Duplicates detected are:`,
+          `${JSON.stringify(conflicts, null, 2)}`,
         ].join("\n"),
       );
     }

packages/babel-core/src/config/validation/options.js

@@ -272,7 +272,8 @@ export type OptionsSource =
   | "configfile"
   | "babelrcfile"
   | "extendsfile"
-  | "preset";
+  | "preset"
+  | "plugin";
 
 type RootPath = $ReadOnly<{
   type: "root",

packages/babel-core/src/config/validation/plugins.js

@@ -84,10 +84,19 @@ export type PluginObject = {
 };
 
 export function validatePluginObject(obj: {}): PluginObject {
+  const rootPath: RootPath = {
+    type: "root",
+    source: "plugin",
+  };
   Object.keys(obj).forEach(key => {
     const validator = VALIDATORS[key];
+    const optLoc = {
+      type: "option",
+      name: key,
+      parent: rootPath,
+    };
 
-    if (validator) validator(key, obj[key]);
+    if (validator) validator(optLoc, obj[key]);
     else throw new Error(`.${key} is not a valid Plugin property`);
   });
 

packages/babel-core/src/transformation/file/file.js

@@ -259,7 +259,7 @@ export default class File {
   ): Error {
     let loc = node && (node.loc || node._loc);
 
-    msg = `${this.opts.filename}: ${msg}`;
+    msg = `${this.opts.filename ?? "unknown"}: ${msg}`;
 
     if (!loc && node) {
       const state = {

packages/babel-core/src/transformation/file/generate.js

@@ -41,7 +41,7 @@ export default function generateCode(
 
     if (typeof result.then === "function") {
       throw new Error(
-        `You appear to be using an async parser plugin, ` +
+        `You appear to be using an async codegen plugin, ` +
           `which your current version of Babel does not support. ` +
           `If you're using a published plugin, ` +
           `you may need to upgrade your @babel/core version.`,

packages/babel-core/src/transformation/index.js

@@ -55,11 +55,29 @@ export function runSync(
     ast,
   );
 
-  transformFile(file, config.passes);
-
   const opts = file.opts;
-  const { outputCode, outputMap } =
-    opts.code !== false ? generateCode(config.passes, file) : {};
+  try {
+    transformFile(file, config.passes);
+  } catch (e) {
+    e.message = `${opts.filename ?? "unknown"}: ${e.message}`;
+    if (!e.code) {
+      e.code = "BABEL_TRANSFORM_ERROR";
+    }
+    throw e;
+  }
+
+  let outputCode, outputMap;
+  try {
+    if (opts.code !== false) {
+      ({ outputCode, outputMap } = generateCode(config.passes, file));
+    }
+  } catch (e) {
+    e.message = `${opts.filename ?? "unknown"}: ${e.message}`;
+    if (!e.code) {
+      e.code = "BABEL_GENERATE_ERROR";
+    }
+    throw e;
+  }
 
   return {
     metadata: file.metadata,

packages/babel-core/src/transformation/normalize-file.js

@@ -107,7 +107,7 @@ function parser(
     } else if (results.length === 1) {
       if (typeof results[0].then === "function") {
         throw new Error(
-          `You appear to be using an async codegen plugin, ` +
+          `You appear to be using an async parser plugin, ` +
             `which your current version of Babel does not support. ` +
             `If you're using a published plugin, you may need to upgrade ` +
             `your @babel/core version.`,
@@ -121,6 +121,7 @@ function parser(
       err.message +=
         "\nConsider renaming the file to '.mjs', or setting sourceType:module " +
         "or sourceType:unambiguous in your Babel config for this file.";
+      // err.code will be changed to BABEL_PARSE_ERROR later.
     }
 
     const { loc, missingPlugin } = err;

packages/babel-core/test/config-chain.js

@@ -1,5 +1,6 @@
 import fs from "fs";
 import path from "path";
+import escapeRegExp from "lodash/escapeRegExp";
 import { loadOptions as loadOptionsOrig } from "../lib";
 
 function fixture(...args) {
@@ -33,7 +34,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          test: new RegExp(fixture("nonexistant-fake")),
+          test: new RegExp(escapeRegExp(fixture("nonexistant-fake"))),
           comments: true,
         });
 
@@ -69,7 +70,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          test: new RegExp(fixture("nonexistant-unknown")),
+          test: new RegExp(escapeRegExp(fixture("nonexistant-unknown"))),
           comments: true,
         });
 
@@ -107,7 +108,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          test: [new RegExp(fixture("nonexistant-fake"))],
+          test: [new RegExp(escapeRegExp(fixture("nonexistant-fake")))],
           comments: true,
         });
 
@@ -143,7 +144,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          test: [new RegExp(fixture("nonexistant-unknown"))],
+          test: [new RegExp(escapeRegExp(fixture("nonexistant-unknown")))],
           comments: true,
         });
 
@@ -183,7 +184,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          include: new RegExp(fixture("nonexistant-fake")),
+          include: new RegExp(escapeRegExp(fixture("nonexistant-fake"))),
           comments: true,
         });
 
@@ -219,7 +220,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          include: new RegExp(fixture("nonexistant-unknown")),
+          include: new RegExp(escapeRegExp(fixture("nonexistant-unknown"))),
           comments: true,
         });
 
@@ -257,7 +258,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          include: [new RegExp(fixture("nonexistant-fake"))],
+          include: [new RegExp(escapeRegExp(fixture("nonexistant-fake")))],
           comments: true,
         });
 
@@ -293,7 +294,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          include: [new RegExp(fixture("nonexistant-unknown"))],
+          include: [new RegExp(escapeRegExp(fixture("nonexistant-unknown")))],
           comments: true,
         });
 
@@ -333,7 +334,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          exclude: new RegExp(fixture("nonexistant-fake")),
+          exclude: new RegExp(escapeRegExp(fixture("nonexistant-fake"))),
           comments: true,
         });
 
@@ -369,7 +370,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          exclude: new RegExp(fixture("nonexistant-unknown")),
+          exclude: new RegExp(escapeRegExp(fixture("nonexistant-unknown"))),
           comments: true,
         });
 
@@ -407,7 +408,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          exclude: [new RegExp(fixture("nonexistant-fake"))],
+          exclude: [new RegExp(escapeRegExp(fixture("nonexistant-fake")))],
           comments: true,
         });
 
@@ -443,7 +444,7 @@ describe("buildConfigChain", function() {
           cwd: fixture("nonexistant-fake"),
           filename: fixture("nonexistant-fake", "src.js"),
           babelrc: false,
-          exclude: [new RegExp(fixture("nonexistant-unknown"))],
+          exclude: [new RegExp(escapeRegExp(fixture("nonexistant-unknown")))],
           comments: true,
         });
 

packages/babel-core/test/config-loading.js

@@ -322,6 +322,21 @@ describe("@babel/core config loading", () => {
         }
       }
     });
+
+    it("should thrown when plugin is not valid", () => {
+      const fooPlugin = {
+        inherits: "inhertis-should-not-be-string",
+      };
+      const opts = {
+        cwd: path.dirname(FILEPATH),
+        filename: FILEPATH,
+        plugins: [fooPlugin],
+      };
+
+      expect(() => loadConfig(opts)).toThrow(
+        /\.inherits must be a function, or undefined/,
+      );
+    });
   });
 
   describe("caller metadata", () => {

packages/babel-core/test/fixtures/plugins/build-code-frame-error/options.json

@@ -1,3 +1,3 @@
 {
-  "throws": "undefined: someMsg\n> 1 | function f() {}"
+  "throws": "unknown: someMsg\n> 1 | function f() {}"
 }

packages/babel-core/test/fixtures/plugins/transform-error/exec.js

@@ -0,0 +1,15 @@
+var code = "function f() {}";
+transform(code, {
+  plugins: [
+    function() {
+      return {
+        visitor: {
+          FunctionDeclaration: function(path) {
+            throw new Error("someMsg");
+          },
+        },
+      };
+    },
+  ],
+  filename: "/fake/path/example.js"
+});

packages/babel-core/test/fixtures/plugins/transform-error/options.json

@@ -0,0 +1,4 @@
+{
+  "throws": "/fake/path/example.js: someMsg",
+  "os": ["linux", "darwin"]
+}

packages/babel-core/test/option-manager.js

@@ -27,14 +27,19 @@ describe("option-manager", () => {
       return { plugin, calls };
     }
 
-    it("should throw if a plugin is repeated", () => {
-      const { calls, plugin } = makePlugin();
+    it("should throw if a plugin is repeated, with information about the repeated plugin", () => {
+      const { calls, plugin } = makePlugin("my-plugin");
 
       expect(() => {
         loadOptions({
-          plugins: [plugin, plugin],
+          plugins: [
+            [plugin, undefined, "my-plugin"],
+            [plugin, undefined, "my-plugin"],
+          ],
         });
-      }).toThrow(/Duplicate plugin\/preset detected/);
+      }).toThrow(
+        /Duplicate plugin\/preset detected.*Duplicates detected are.*my-plugin.*my-plugin/ms,
+      );
       expect(calls).toEqual([]);
     });
 

packages/babel-generator/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/generator",
-  "version": "7.6.0",
+  "version": "7.6.4",
   "description": "Turns an AST into code.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -14,14 +14,13 @@
     "lib"
   ],
   "dependencies": {
-    "@babel/types": "^7.6.0",
+    "@babel/types": "^7.6.3",
     "jsesc": "^2.5.1",
     "lodash": "^4.17.13",
-    "source-map": "^0.5.0",
-    "trim-right": "^1.0.1"
+    "source-map": "^0.5.0"
   },
   "devDependencies": {
-    "@babel/helper-fixtures": "^7.6.0",
-    "@babel/parser": "^7.6.0"
+    "@babel/helper-fixtures": "^7.6.3",
+    "@babel/parser": "^7.6.4"
   }
 }

packages/babel-generator/src/buffer.js

@@ -1,5 +1,4 @@
 import type SourceMap from "./source-map";
-import trimRight from "trim-right";
 
 const SPACES_RE = /^[ \t]+$/;
 
@@ -43,7 +42,7 @@ export default class Buffer {
     const result = {
       // Whatever trim is used here should not execute a regex against the
       // source string since it may be arbitrarily large after all transformations
-      code: trimRight(this._buf.join("")),
+      code: this._buf.join("").trimRight(),
       map: null,
       rawMappings: map && map.getRawMappings(),
     };

packages/babel-generator/src/source-map.js

@@ -24,14 +24,20 @@ export default class SourceMap {
 
       const code = this._code;
       if (typeof code === "string") {
-        map.setSourceContent(this._opts.sourceFileName, code);
+        map.setSourceContent(
+          this._opts.sourceFileName.replace(/\\/g, "/"),
+          code,
+        );
       } else if (typeof code === "object") {
         Object.keys(code).forEach(sourceFileName => {
-          map.setSourceContent(sourceFileName, code[sourceFileName]);
+          map.setSourceContent(
+            sourceFileName.replace(/\\/g, "/"),
+            code[sourceFileName],
+          );
         });
       }
 
-      this._rawMappings.forEach(map.addMapping, map);
+      this._rawMappings.forEach(mapping => map.addMapping(mapping), map);
     }
 
     return this._cachedMap.toJSON();
@@ -83,7 +89,10 @@ export default class SourceMap {
         line: generatedLine,
         column: generatedColumn,
       },
-      source: line == null ? undefined : filename || this._opts.sourceFileName,
+      source:
+        line == null
+          ? undefined
+          : (filename || this._opts.sourceFileName).replace(/\\/g, "/"),
       original:
         line == null
           ? undefined

packages/babel-generator/test/fixtures/flow/declare-statements/input.js

@@ -11,13 +11,13 @@ declare class A { static [ indexer: number]: string }
 declare class A { static () : number }
 declare class B { (): number }
 declare class A mixins B<T>, C {}
-declare type A = string
+declare type A1 = string
 declare type T<U> = { [k:string]: U }
-declare type B = {
+declare type B1 = {
   fn?: (foo: string) => void,
 }
-declare interface I { foo: string }
-declare interface I<T> { foo: T }
+declare interface I1 { foo: string }
+declare interface I2<T> { foo: T }
 declare module.exports: { foo: string }
 declare opaque type Foo<T>: Bar<T>;
 declare opaque type ID;

packages/babel-generator/test/fixtures/flow/declare-statements/output.js

@@ -22,17 +22,17 @@ declare class B {
   (): number
 }
 declare class A mixins B<T>, C {}
-declare type A = string;
+declare type A1 = string;
 declare type T<U> = {
   [k: string]: U
 };
-declare type B = {
+declare type B1 = {
   fn?: (foo: string) => void
 };
-declare interface I {
+declare interface I1 {
   foo: string
 }
-declare interface I<T> {
+declare interface I2<T> {
   foo: T
 }
 declare module.exports: {

packages/babel-generator/test/fixtures/flow/def-site-variance/input.js

@@ -5,10 +5,10 @@ type T2 = { +p: T };
 type T3 = { -p: T };
 type T4 = { +[k:K]: V };
 type T5 = { -[k:K]: V };
-interface I { +p: T }
-interface I { -p: T }
-interface I { +[k:K]: V }
-interface I { -[k:K]: V }
+interface I1 { +p: T }
+interface I2 { -p: T }
+interface I3 { +[k:K]: V }
+interface I4 { -[k:K]: V }
 declare class I { +p: T }
 declare class I { -p: T }
 declare class I { +[k:K]: V }

packages/babel-generator/test/fixtures/flow/def-site-variance/output.js

@@ -15,16 +15,16 @@ type T4 = {
 type T5 = {
   -[k: K]: V
 };
-interface I {
+interface I1 {
   +p: T
 }
-interface I {
+interface I2 {
   -p: T
 }
-interface I {
+interface I3 {
   +[k: K]: V
 }
-interface I {
+interface I4 {
   -[k: K]: V
 }
 declare class I {

packages/babel-generator/test/fixtures/flow/internal-slot/input.js

@@ -1,7 +1,7 @@
 declare class C { static [[foo]]: T }
 declare class C { [[foo]]: T }
-interface I { [[foo]]: X }
-interface I { [[foo]](): X }
+interface I1 { [[foo]]: X }
+interface I2 { [[foo]](): X }
 type T1 = { [[foo]]: X }
 type T2 = { [[foo]](): X }
 type T3 = { [[foo]]?: X }

packages/babel-generator/test/fixtures/flow/internal-slot/output.js

@@ -4,10 +4,10 @@ declare class C {
 declare class C {
   [[foo]]: T
 }
-interface I {
+interface I1 {
   [[foo]]: X
 }
-interface I {
+interface I2 {
   [[foo]]() => X
 }
 type T1 = {

packages/babel-generator/test/fixtures/flow/iterator-inside-interface/input.js

@@ -1,7 +1,7 @@
-interface A {
+interface A1 {
   @@iterator(): Iterator<File>;
 }
 
-interface A {
+interface A2 {
   @@asyncIterator(): Iterator<File>;
 }

packages/babel-generator/test/fixtures/flow/iterator-inside-interface/output.js

@@ -1,6 +1,6 @@
-interface A {
+interface A1 {
   @@iterator(): Iterator<File>
 }
-interface A {
+interface A2 {
   @@asyncIterator(): Iterator<File>
 }

packages/babel-helper-fixtures/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/helper-fixtures",
-  "version": "7.6.0",
+  "version": "7.6.3",
   "description": "Helper function to support fixtures",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "license": "MIT",
@@ -11,7 +11,6 @@
   "main": "lib/index.js",
   "dependencies": {
     "lodash": "^4.17.13",
-    "semver": "^5.3.0",
-    "try-resolve": "^1.0.0"
+    "semver": "^5.3.0"
   }
 }

packages/babel-helper-fixtures/src/index.js

@@ -1,6 +1,4 @@
 import cloneDeep from "lodash/cloneDeep";
-import trimEnd from "lodash/trimEnd";
-import resolve from "try-resolve";
 import clone from "lodash/clone";
 import extend from "lodash/extend";
 import semver from "semver";
@@ -36,6 +34,13 @@ type Suite = {
   filename: string,
 };
 
+function tryResolve(module) {
+  try {
+    return require.resolve(module);
+  } catch (e) {
+    return null;
+  }
+}
 function assertDirectory(loc) {
   if (!fs.statSync(loc).isDirectory()) {
     throw new Error(`Expected ${loc} to be a directory.`);
@@ -77,7 +82,7 @@ export default function get(entryLoc): Array<Suite> {
   const suites = [];
 
   let rootOpts = {};
-  const rootOptsLoc = resolve(entryLoc + "/options");
+  const rootOptsLoc = tryResolve(entryLoc + "/options");
   if (rootOptsLoc) rootOpts = require(rootOptsLoc);
 
   for (const suiteName of fs.readdirSync(entryLoc)) {
@@ -93,7 +98,7 @@ export default function get(entryLoc): Array<Suite> {
     assertDirectory(suite.filename);
     suites.push(suite);
 
-    const suiteOptsLoc = resolve(suite.filename + "/options");
+    const suiteOptsLoc = tryResolve(suite.filename + "/options");
     if (suiteOptsLoc) suite.options = require(suiteOptsLoc);
 
     for (const taskName of fs.readdirSync(suite.filename)) {
@@ -140,7 +145,7 @@ export default function get(entryLoc): Array<Suite> {
 
       const taskOpts = cloneDeep(suite.options);
 
-      const taskOptsLoc = resolve(taskDir + "/options");
+      const taskOptsLoc = tryResolve(taskDir + "/options");
       if (taskOptsLoc) extend(taskOpts, require(taskOptsLoc));
 
       const test = {
@@ -187,6 +192,26 @@ export default function get(entryLoc): Array<Suite> {
         delete taskOpts.minNodeVersion;
       }
 
+      if (taskOpts.os) {
+        let os = taskOpts.os;
+
+        if (!Array.isArray(os) && typeof os !== "string") {
+          throw new Error(
+            `'os' should be either string or string array: ${taskOpts.os}`,
+          );
+        }
+
+        if (typeof os === "string") {
+          os = [os];
+        }
+
+        if (!os.includes(process.platform)) {
+          return;
+        }
+
+        delete taskOpts.os;
+      }
+
       // traceur checks
 
       if (test.exec.code.indexOf("// Async.") >= 0) {
@@ -275,7 +300,7 @@ export function multiple(entryLoc, ignore?: Array<string>) {
 
 export function readFile(filename) {
   if (fs.existsSync(filename)) {
-    let file = trimEnd(fs.readFileSync(filename, "utf8"));
+    let file = fs.readFileSync(filename, "utf8").trimRight();
     file = file.replace(/\r\n/g, "\n");
     return file;
   } else {

packages/babel-helper-transform-fixture-test-runner/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/helper-transform-fixture-test-runner",
-  "version": "7.6.0",
+  "version": "7.6.4",
   "description": "Transform test runner for @babel/helper-fixtures module",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -12,8 +12,8 @@
   "main": "lib/index.js",
   "dependencies": {
     "@babel/code-frame": "^7.5.5",
-    "@babel/core": "^7.6.0",
-    "@babel/helper-fixtures": "^7.6.0",
+    "@babel/core": "^7.6.4",
+    "@babel/helper-fixtures": "^7.6.3",
     "@babel/polyfill": "^7.6.0",
     "babel-check-duplicated-nodes": "^1.0.0",
     "jest": "^24.8.0",

packages/babel-helper-transform-fixture-test-runner/src/index.js

@@ -295,12 +295,22 @@ function validateFile(actualCode, expectedLoc, expectedCode) {
 }
 
 function normalizeOutput(code) {
-  return code
+  let result = code
     .trim()
     .replace(
       new RegExp(escapeRegExp(path.resolve(__dirname, "../../../")), "g"),
       "<CWD>",
     );
+  if (process.platform === "win32") {
+    result = result.replace(
+      new RegExp(
+        escapeRegExp(path.resolve(__dirname, "../../../").replace(/\\/g, "/")),
+        "g",
+      ),
+      "<CWD>",
+    );
+  }
+  return result;
 }
 
 const toEqualFile = () => ({

packages/babel-helpers/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/helpers",
-  "version": "7.6.0",
+  "version": "7.6.2",
   "description": "Collection of helper functions used by Babel transforms.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -12,7 +12,7 @@
   "main": "lib/index.js",
   "dependencies": {
     "@babel/template": "^7.6.0",
-    "@babel/traverse": "^7.6.0",
+    "@babel/traverse": "^7.6.2",
     "@babel/types": "^7.6.0"
   },
   "devDependencies": {

packages/babel-helpers/src/helpers.js

@@ -936,7 +936,7 @@ helpers.iterableToArrayLimit = helper("7.0.0-beta.0")`
   export default function _iterableToArrayLimit(arr, i) {
     // this is an expanded form of \`for...of\` that properly supports abrupt completions of
     // iterators etc. variable names have been minimised to reduce the size of this massive
-    // helper. sometimes spec compliancy is annoying :(
+    // helper. sometimes spec compliance is annoying :(
     //
     // _n = _iteratorNormalCompletion
     // _d = _didIteratorError

packages/babel-node/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/node",
-  "version": "7.6.0",
+  "version": "7.6.3",
   "description": "Babel command line",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -19,19 +19,20 @@
     "compiler"
   ],
   "dependencies": {
-    "@babel/polyfill": "^7.6.0",
-    "@babel/register": "^7.6.0",
+    "@babel/register": "^7.6.2",
     "commander": "^2.8.1",
+    "core-js": "^3.2.1",
     "lodash": "^4.17.13",
     "node-environment-flags": "^1.0.5",
+    "regenerator-runtime": "^0.13.3",
     "v8flags": "^3.1.1"
   },
   "peerDependencies": {
     "@babel/core": "^7.0.0-0"
   },
   "devDependencies": {
-    "@babel/core": "^7.6.0",
-    "@babel/helper-fixtures": "^7.6.0",
+    "@babel/core": "^7.6.3",
+    "@babel/helper-fixtures": "^7.6.3",
     "fs-readdir-recursive": "^1.0.0",
     "output-file-sync": "^2.0.0"
   },

packages/babel-node/src/_babel-node.js

@@ -5,7 +5,8 @@ import path from "path";
 import repl from "repl";
 import * as babel from "@babel/core";
 import vm from "vm";
-import "@babel/polyfill";
+import "core-js/stable";
+import "regenerator-runtime/runtime";
 import register from "@babel/register";
 
 import pkg from "../package.json";

packages/babel-node/src/babel-node.js

@@ -93,9 +93,6 @@ getV8Flags(function(err, v8Flags) {
         }
       });
     });
-    process.on("SIGINT", () => {
-      proc.kill("SIGINT");
-      process.exit(1);
-    });
+    process.on("SIGINT", () => proc.kill("SIGINT"));
   }
 });

packages/babel-node/test/index.js

@@ -198,7 +198,7 @@ fs.readdirSync(fixtureLoc).forEach(function(binName) {
         opts.inFiles[".babelrc"] = helper.readFile(babelrcLoc);
       }
 
-      it(testName, buildTest(binName, testName, opts));
+      it(testName, buildTest(binName, testName, opts), 20000);
     });
   });
 });

packages/babel-parser/CHANGELOG.md

@@ -2,7 +2,7 @@
 
 > **Tags:**
 > - :boom:       [Breaking Change]
-> - :eyeglasses: [Spec Compliancy]
+> - :eyeglasses: [Spec Compliance]
 > - :rocket:     [New Feature]
 > - :bug:        [Bug Fix]
 > - :memo:       [Documentation]
@@ -56,7 +56,7 @@ See the [Babel Changelog](https://github.com/babel/babel/blob/master/CHANGELOG.m
 
 ## 7.0.0-beta.7 (2017-03-22)
 
-### Spec Compliancy
+### Spec Compliance
 * Remove babylon plugin for template revision since it's stage-4 (#426) (Henry Zhu)
 
 ### Bug Fix
@@ -200,7 +200,7 @@ declare module "C" {
 }
 ```
 
-### :eyeglasses: Spec Compliancy
+### :eyeglasses: Spec Compliance
 
 Forbid semicolons after decorators in classes ([#352](https://github.com/babel/babylon/pull/352)) (Kevin Gibbons)
 
@@ -305,7 +305,7 @@ AST spec: fix casing of `RegExpLiteral` ([#318](https://github.com/babel/babylon
 
 ## 6.15.0 (2017-01-10)
 
-### :eyeglasses: Spec Compliancy
+### :eyeglasses: Spec Compliance
 
 Add support for Flow shorthand import type ([#267](https://github.com/babel/babylon/pull/267)) (Jeff Morrison)
 
@@ -411,7 +411,7 @@ Will include all parser plugins instead of specifying each one individually. Use
 
 ## 6.14.0 (2016-11-16)
 
-### :eyeglasses: Spec Compliancy
+### :eyeglasses: Spec Compliance
 
 Throw error for reserved words `enum` and `await` ([#195](https://github.com/babel/babylon/pull/195)) (Kai Cataldo)
 
@@ -491,7 +491,7 @@ With that test case, there was a ~95ms savings by removing the need for node to
 
 ## v6.13.0 (2016-10-21)
 
-### :eyeglasses: Spec Compliancy
+### :eyeglasses: Spec Compliance
 
 Property variance type annotations for Flow plugin ([#161](https://github.com/babel/babylon/pull/161)) (Sam Goldman)
 
@@ -549,7 +549,7 @@ Fixes two tests that are failing after the merge of #172 ([#177](https://github.
 
 ## v6.12.0 (2016-10-14)
 
-### :eyeglasses: Spec Compliancy
+### :eyeglasses: Spec Compliance
 
 Implement import() syntax ([#163](https://github.com/babel/babylon/pull/163)) (Jordan Gensler)
 
@@ -643,7 +643,7 @@ export const { foo: [ ,, qux7 ] } = bar;
 
 ## v6.11.5 (2016-10-12)
 
-### :eyeglasses: Spec Compliancy
+### :eyeglasses: Spec Compliance
 
 Fix: Check for duplicate named exports in exported destructuring assignments ([#144](https://github.com/babel/babylon/pull/144)) (Kai Cataldo)
 
@@ -689,7 +689,7 @@ Temporary rollback for erroring on trailing comma with spread (#154) (Henry Zhu)
 
 ## v6.11.3 (2016-10-01)
 
-### :eyeglasses: Spec Compliancy
+### :eyeglasses: Spec Compliance
 
 Add static errors for object rest (#149) ([@danez](https://github.com/danez))
 
@@ -782,7 +782,7 @@ export toString from './toString';
 
 ## 6.11.0 (2016-09-22)
 
-### Spec Compliancy (will break CI)
+### Spec Compliance (will break CI)
 
 - Disallow duplicate named exports ([#107](https://github.com/babel/babylon/pull/107)) @kaicataldo
 
@@ -862,9 +862,9 @@ for (+i in {});
 
 ## 6.10.0 (2016-09-19)
 
-> We plan to include some spec compliancy bugs in patch versions. An example was the multiple default exports issue.
+> We plan to include some spec compliance bugs in patch versions. An example was the multiple default exports issue.
 
-### Spec Compliancy
+### Spec Compliance
 
 * Implement ES2016 check for simple parameter list in strict mode ([#106](https://github.com/babel/babylon/pull/106)) (Timothy Gu)
 
@@ -1023,7 +1023,7 @@ declare module "foo" {
 - The existential type `*` is not a valid type parameter.
 - The existential type `*` is a primary type
 
-### Spec Compliancy
+### Spec Compliance
 - The param list for type parameter declarations now consists of `TypeParameter` nodes
 - New `TypeParameter` AST Node (replaces using the `Identifier` node before)
 

packages/babel-parser/package.json

@@ -1,12 +1,12 @@
 {
   "name": "@babel/parser",
-  "version": "7.6.0",
+  "version": "7.6.4",
   "description": "A JavaScript parser",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
   "license": "MIT",
   "publishConfig": {
-    "tag": "next"
+    "access": "public"
   },
   "keywords": [
     "babel",
@@ -29,7 +29,7 @@
   },
   "devDependencies": {
     "@babel/code-frame": "^7.5.5",
-    "@babel/helper-fixtures": "^7.6.0",
+    "@babel/helper-fixtures": "^7.6.3",
     "charcodes": "^0.2.0",
     "unicode-12.0.0": "^0.7.9"
   },

packages/babel-parser/src/parser/comments.js

@@ -38,15 +38,31 @@ export default class CommentsParser extends BaseParser {
     this.state.leadingComments.push(comment);
   }
 
-  adjustCommentsAfterTrailingComma(node: Node, elements: Node[]) {
-    if (elements.length === 0) {
-      return;
-    }
+  adjustCommentsAfterTrailingComma(
+    node: Node,
+    elements: (Node | null)[],
+    // When the current node is followed by a token which hasn't a respective AST node, we
+    // need to take all the trailing comments to prevent them from being attached to an
+    // unrelated node. e.g. in
+    //     var { x } /* cmt */ = { y }
+    // we don't want /* cmt */ to be attached to { y }.
+    // On the other hand, in
+    //     fn(x) [new line] /* cmt */ [new line] y
+    // /* cmt */ is both a trailing comment of fn(x) and a leading comment of y
+    takeAllComments?: boolean,
+  ) {
     if (this.state.leadingComments.length === 0) {
       return;
     }
 
-    const lastElement = last(elements);
+    let lastElement = null;
+    let i = elements.length;
+    while (lastElement === null && i > 0) {
+      lastElement = elements[--i];
+    }
+    if (lastElement === null) {
+      return;
+    }
 
     for (let j = 0; j < this.state.leadingComments.length; j++) {
       if (
@@ -58,10 +74,16 @@ export default class CommentsParser extends BaseParser {
     }
 
     const newTrailingComments = [];
-    while (this.state.leadingComments.length) {
-      const leadingComment = this.state.leadingComments.shift();
+    for (let i = 0; i < this.state.leadingComments.length; i++) {
+      const leadingComment = this.state.leadingComments[i];
       if (leadingComment.end < node.end) {
         newTrailingComments.push(leadingComment);
+
+        // Perf: we don't need to splice if we are going to reset the array anyway
+        if (!takeAllComments) {
+          this.state.leadingComments.splice(i, 1);
+          i--;
+        }
       } else {
         if (node.trailingComments === undefined) {
           node.trailingComments = [];
@@ -69,6 +91,7 @@ export default class CommentsParser extends BaseParser {
         node.trailingComments.push(leadingComment);
       }
     }
+    if (takeAllComments) this.state.leadingComments = [];
 
     if (newTrailingComments.length > 0) {
       lastElement.trailingComments = newTrailingComments;
@@ -129,16 +152,20 @@ export default class CommentsParser extends BaseParser {
     if (firstChild) {
       switch (node.type) {
         case "ObjectExpression":
-        case "ObjectPattern":
           this.adjustCommentsAfterTrailingComma(node, node.properties);
           break;
+        case "ObjectPattern":
+          this.adjustCommentsAfterTrailingComma(node, node.properties, true);
+          break;
         case "CallExpression":
           this.adjustCommentsAfterTrailingComma(node, node.arguments);
           break;
         case "ArrayExpression":
-        case "ArrayPattern":
           this.adjustCommentsAfterTrailingComma(node, node.elements);
           break;
+        case "ArrayPattern":
+          this.adjustCommentsAfterTrailingComma(node, node.elements, true);
+          break;
       }
     } else if (
       this.state.commentPreviousNode &&
@@ -147,9 +174,11 @@ export default class CommentsParser extends BaseParser {
         (this.state.commentPreviousNode.type === "ExportSpecifier" &&
           node.type !== "ExportSpecifier"))
     ) {
-      this.adjustCommentsAfterTrailingComma(node, [
-        this.state.commentPreviousNode,
-      ]);
+      this.adjustCommentsAfterTrailingComma(
+        node,
+        [this.state.commentPreviousNode],
+        true,
+      );
     }
 
     if (lastChild) {

packages/babel-parser/src/parser/expression.js

@@ -168,9 +168,6 @@ export default class ExpressionParser extends LValParser {
       }
     }
 
-    const oldCommaAfterSpreadAt = this.state.commaAfterSpreadAt;
-    this.state.commaAfterSpreadAt = -1;
-
     let failOnShorthandAssign;
     if (refShorthandDefaultPos) {
       failOnShorthandAssign = false;
@@ -230,9 +227,6 @@ export default class ExpressionParser extends LValParser {
         );
       }
 
-      if (patternErrorMsg) this.checkCommaAfterRestFromSpread();
-      this.state.commaAfterSpreadAt = oldCommaAfterSpreadAt;
-
       this.next();
       node.right = this.parseMaybeAssign(noIn);
       return this.finishNode(node, "AssignmentExpression");
@@ -240,8 +234,6 @@ export default class ExpressionParser extends LValParser {
       this.unexpected(refShorthandDefaultPos.start);
     }
 
-    this.state.commaAfterSpreadAt = oldCommaAfterSpreadAt;
-
     return left;
   }
 
@@ -490,11 +482,7 @@ export default class ExpressionParser extends LValParser {
   // Parse unary operators, both prefix and postfix.
 
   parseMaybeUnary(refShorthandDefaultPos: ?Pos): N.Expression {
-    if (
-      this.isContextual("await") &&
-      (this.scope.inAsync ||
-        (!this.scope.inFunction && this.options.allowAwaitOutsideFunction))
-    ) {
+    if (this.isContextual("await") && this.isAwaitAllowed()) {
       return this.parseAwait();
     } else if (this.state.type.prefix) {
       const node = this.startNode();
@@ -578,21 +566,16 @@ export default class ExpressionParser extends LValParser {
     startLoc: Position,
     noCalls?: ?boolean,
   ): N.Expression {
-    const maybeAsyncArrow = this.atPossibleAsync(base);
-
     const state = {
       optionalChainMember: false,
+      maybeAsyncArrow: this.atPossibleAsync(base),
       stop: false,
     };
     do {
-      base = this.parseSubscript(
-        base,
-        startPos,
-        startLoc,
-        noCalls,
-        state,
-        maybeAsyncArrow,
-      );
+      base = this.parseSubscript(base, startPos, startLoc, noCalls, state);
+
+      // After parsing a subscript, this isn't "async" for sure.
+      state.maybeAsyncArrow = false;
     } while (!state.stop);
     return base;
   }
@@ -607,7 +590,6 @@ export default class ExpressionParser extends LValParser {
     startLoc: Position,
     noCalls: ?boolean,
     state: N.ParseSubscriptState,
-    maybeAsyncArrow: boolean,
   ): N.Expression {
     if (!noCalls && this.eat(tt.doubleColon)) {
       const node = this.startNodeAt(startPos, startLoc);
@@ -623,7 +605,7 @@ export default class ExpressionParser extends LValParser {
     } else if (this.match(tt.questionDot)) {
       this.expectPlugin("optionalChaining");
       state.optionalChainMember = true;
-      if (noCalls && this.lookahead().type === tt.parenL) {
+      if (noCalls && this.lookaheadCharCode() === charCodes.leftParenthesis) {
         state.stop = true;
         return base;
       }
@@ -655,6 +637,12 @@ export default class ExpressionParser extends LValParser {
       node.object = base;
       node.property = this.parseMaybePrivateName();
       node.computed = false;
+      if (
+        node.property.type === "PrivateName" &&
+        node.object.type === "Super"
+      ) {
+        this.raise(startPos, "Private fields can't be accessed on super");
+      }
       if (state.optionalChainMember) {
         node.optional = false;
         return this.finishNode(node, "OptionalMemberExpression");
@@ -676,22 +664,20 @@ export default class ExpressionParser extends LValParser {
       const oldYieldPos = this.state.yieldPos;
       const oldAwaitPos = this.state.awaitPos;
       this.state.maybeInArrowParameters = true;
-      this.state.yieldPos = 0;
-      this.state.awaitPos = 0;
+      this.state.yieldPos = -1;
+      this.state.awaitPos = -1;
 
       this.next();
 
       let node = this.startNodeAt(startPos, startLoc);
       node.callee = base;
 
-      const oldCommaAfterSpreadAt = this.state.commaAfterSpreadAt;
-      this.state.commaAfterSpreadAt = -1;
-
       node.arguments = this.parseCallExpressionArguments(
         tt.parenR,
-        maybeAsyncArrow,
+        state.maybeAsyncArrow,
         base.type === "Import",
         base.type !== "Super",
+        node,
       );
       if (!state.optionalChainMember) {
         this.finishCallExpression(node);
@@ -699,11 +685,9 @@ export default class ExpressionParser extends LValParser {
         this.finishOptionalCallExpression(node);
       }
 
-      if (maybeAsyncArrow && this.shouldParseAsyncArrow()) {
+      if (state.maybeAsyncArrow && this.shouldParseAsyncArrow()) {
         state.stop = true;
 
-        this.checkCommaAfterRestFromSpread();
-
         node = this.parseAsyncArrowFromCallExpression(
           this.startNodeAt(startPos, startLoc),
           node,
@@ -716,12 +700,37 @@ export default class ExpressionParser extends LValParser {
 
         // We keep the old value if it isn't null, for cases like
         //   (x = async(yield)) => {}
-        this.state.yieldPos = oldYieldPos || this.state.yieldPos;
-        this.state.awaitPos = oldAwaitPos || this.state.awaitPos;
+        //
+        // Hi developer of the future :) If you are implementing generator
+        // arrow functions, please read the note below about "await" and
+        // verify if the same logic is needed for yield.
+        if (oldYieldPos !== -1) this.state.yieldPos = oldYieldPos;
+
+        // Await is trickier than yield. When parsing a possible arrow function
+        // (e.g. something starting with `async(`) we don't know if its possible
+        // parameters will actually be inside an async arrow function or if it is
+        // a normal call expression.
+        // If it ended up being a call expression, if we are in a context where
+        // await expression are disallowed (and thus "await" is an identifier)
+        // we must be careful not to leak this.state.awaitPos to an even outer
+        // context, where "await" could not be an identifier.
+        // For example, this code is valid because "await" isn't directly inside
+        // an async function:
+        //
+        //     async function a() {
+        //       function b(param = async (await)) {
+        //       }
+        //     }
+        //
+        if (
+          (!this.isAwaitAllowed() && !oldMaybeInArrowParameters) ||
+          oldAwaitPos !== -1
+        ) {
+          this.state.awaitPos = oldAwaitPos;
+        }
       }
 
       this.state.maybeInArrowParameters = oldMaybeInArrowParameters;
-      this.state.commaAfterSpreadAt = oldCommaAfterSpreadAt;
 
       return node;
     } else if (this.match(tt.backQuote)) {
@@ -803,6 +812,7 @@ export default class ExpressionParser extends LValParser {
     possibleAsyncArrow: boolean,
     dynamicImport?: boolean,
     allowPlaceholder?: boolean,
+    nodeForExtra?: ?N.Node,
   ): $ReadOnlyArray<?N.Expression> {
     const elts = [];
     let innerParenStart;
@@ -815,13 +825,21 @@ export default class ExpressionParser extends LValParser {
         first = false;
       } else {
         this.expect(tt.comma);
-        if (this.eat(close)) {
+        if (this.match(close)) {
           if (dynamicImport) {
             this.raise(
               this.state.lastTokStart,
               "Trailing comma is disallowed inside import(...) arguments",
             );
           }
+          if (nodeForExtra) {
+            this.addExtra(
+              nodeForExtra,
+              "trailingComma",
+              this.state.lastTokStart,
+            );
+          }
+          this.next();
           break;
         }
       }
@@ -861,7 +879,12 @@ export default class ExpressionParser extends LValParser {
     call: N.CallExpression,
   ): N.ArrowFunctionExpression {
     this.expect(tt.arrow);
-    this.parseArrowExpression(node, call.arguments, true);
+    this.parseArrowExpression(
+      node,
+      call.arguments,
+      true,
+      call.extra?.trailingComma,
+    );
     return node;
   }
 
@@ -1024,6 +1047,7 @@ export default class ExpressionParser extends LValParser {
           tt.bracketR,
           true,
           refShorthandDefaultPos,
+          node,
         );
         if (!this.state.maybeInArrowParameters) {
           // This could be an array pattern:
@@ -1231,8 +1255,8 @@ export default class ExpressionParser extends LValParser {
     const oldAwaitPos = this.state.awaitPos;
     const oldInFSharpPipelineDirectBody = this.state.inFSharpPipelineDirectBody;
     this.state.maybeInArrowParameters = true;
-    this.state.yieldPos = 0;
-    this.state.awaitPos = 0;
+    this.state.yieldPos = -1;
+    this.state.awaitPos = -1;
     this.state.inFSharpPipelineDirectBody = false;
 
     const innerStartPos = this.state.start;
@@ -1267,7 +1291,7 @@ export default class ExpressionParser extends LValParser {
           ),
         );
 
-        this.checkCommaAfterRest();
+        this.checkCommaAfterRest(charCodes.rightParenthesis);
 
         break;
       } else {
@@ -1310,8 +1334,8 @@ export default class ExpressionParser extends LValParser {
 
     // We keep the old value if it isn't null, for cases like
     //   (x = (yield)) => {}
-    this.state.yieldPos = oldYieldPos || this.state.yieldPos;
-    this.state.awaitPos = oldAwaitPos || this.state.awaitPos;
+    if (oldYieldPos !== -1) this.state.yieldPos = oldYieldPos;
+    if (oldAwaitPos !== -1) this.state.awaitPos = oldAwaitPos;
 
     if (!exprList.length) {
       this.unexpected(this.state.lastTokStart);
@@ -1482,7 +1506,11 @@ export default class ExpressionParser extends LValParser {
         first = false;
       } else {
         this.expect(tt.comma);
-        if (this.eat(tt.braceR)) break;
+        if (this.match(tt.braceR)) {
+          this.addExtra(node, "trailingComma", this.state.lastTokStart);
+          this.next();
+          break;
+        }
       }
 
       const prop = this.parseObjectMember(isPattern, refShorthandDefaultPos);
@@ -1550,7 +1578,7 @@ export default class ExpressionParser extends LValParser {
         this.next();
         // Don't use parseRestBinding() as we only allow Identifier here.
         prop.argument = this.parseIdentifier();
-        this.checkCommaAfterRest();
+        this.checkCommaAfterRest(charCodes.rightCurlyBrace);
         return this.finishNode(prop, "RestElement");
       }
 
@@ -1804,8 +1832,8 @@ export default class ExpressionParser extends LValParser {
   ): T {
     const oldYieldPos = this.state.yieldPos;
     const oldAwaitPos = this.state.awaitPos;
-    this.state.yieldPos = 0;
-    this.state.awaitPos = 0;
+    this.state.yieldPos = -1;
+    this.state.awaitPos = -1;
 
     this.initFunction(node, isAsync);
     node.generator = !!isGenerator;
@@ -1834,6 +1862,7 @@ export default class ExpressionParser extends LValParser {
     node: N.ArrowFunctionExpression,
     params: ?(N.Expression[]),
     isAsync: boolean,
+    trailingCommaPos: ?number,
   ): N.ArrowFunctionExpression {
     this.scope.enter(functionFlags(isAsync, false) | SCOPE_ARROW);
     this.initFunction(node, isAsync);
@@ -1842,10 +1871,10 @@ export default class ExpressionParser extends LValParser {
     const oldYieldPos = this.state.yieldPos;
     const oldAwaitPos = this.state.awaitPos;
     this.state.maybeInArrowParameters = false;
-    this.state.yieldPos = 0;
-    this.state.awaitPos = 0;
+    this.state.yieldPos = -1;
+    this.state.awaitPos = -1;
 
-    if (params) this.setArrowFunctionParameters(node, params);
+    if (params) this.setArrowFunctionParameters(node, params, trailingCommaPos);
     this.parseFunctionBody(node, true);
 
     this.scope.exit();
@@ -1859,11 +1888,13 @@ export default class ExpressionParser extends LValParser {
   setArrowFunctionParameters(
     node: N.ArrowFunctionExpression,
     params: N.Expression[],
+    trailingCommaPos: ?number,
   ): void {
     node.params = this.toAssignableList(
       params,
       true,
       "arrow function parameters",
+      trailingCommaPos,
     );
   }
 
@@ -1975,7 +2006,7 @@ export default class ExpressionParser extends LValParser {
         node.params[i],
         BIND_VAR,
         allowDuplicates ? null : nameHash,
-        "function paramter list",
+        "function parameter list",
       );
     }
   }
@@ -1990,6 +2021,7 @@ export default class ExpressionParser extends LValParser {
     close: TokenType,
     allowEmpty?: boolean,
     refShorthandDefaultPos?: ?Pos,
+    nodeForExtra?: ?N.Node,
   ): $ReadOnlyArray<?N.Expression> {
     const elts = [];
     let first = true;
@@ -1999,7 +2031,17 @@ export default class ExpressionParser extends LValParser {
         first = false;
       } else {
         this.expect(tt.comma);
-        if (this.eat(close)) break;
+        if (this.match(close)) {
+          if (nodeForExtra) {
+            this.addExtra(
+              nodeForExtra,
+              "trailingComma",
+              this.state.lastTokStart,
+            );
+          }
+          this.next();
+          break;
+        }
       }
 
       elts.push(this.parseExprListItem(allowEmpty, refShorthandDefaultPos));
@@ -2066,6 +2108,11 @@ export default class ExpressionParser extends LValParser {
 
     if (this.match(tt.name)) {
       name = this.state.value;
+
+      // An escaped identifier whose value is the same as a keyword
+      if (!liberal && this.state.containsEsc && isKeyword(name)) {
+        this.raise(this.state.pos, `Escape sequence in keyword ${name}`);
+      }
     } else if (this.state.type.keyword) {
       name = this.state.type.keyword;
 
@@ -2112,11 +2159,18 @@ export default class ExpressionParser extends LValParser {
       );
     }
 
-    if (this.scope.inAsync && word === "await") {
-      this.raise(
-        startLoc,
-        "Can not use 'await' as identifier inside an async function",
-      );
+    if (word === "await") {
+      if (this.scope.inAsync) {
+        this.raise(
+          startLoc,
+          "Can not use 'await' as identifier inside an async function",
+        );
+      } else if (
+        this.state.awaitPos === -1 &&
+        (this.state.maybeInArrowParameters || this.isAwaitAllowed())
+      ) {
+        this.state.awaitPos = this.state.start;
+      }
     }
 
     if (this.state.inClassProperty && word === "arguments") {
@@ -2146,10 +2200,16 @@ export default class ExpressionParser extends LValParser {
     }
   }
 
+  isAwaitAllowed(): boolean {
+    if (this.scope.inFunction) return this.scope.inAsync;
+    if (this.options.allowAwaitOutsideFunction) return true;
+    return false;
+  }
+
   // Parses await expression inside async function.
 
   parseAwait(): N.AwaitExpression {
-    if (!this.state.awaitPos) {
+    if (this.state.awaitPos === -1) {
       this.state.awaitPos = this.state.start;
     }
     const node = this.startNode();
@@ -2178,7 +2238,7 @@ export default class ExpressionParser extends LValParser {
   // Parses yield expression inside generator.
 
   parseYield(noIn?: ?boolean): N.YieldExpression {
-    if (!this.state.yieldPos) {
+    if (this.state.yieldPos === -1) {
       this.state.yieldPos = this.state.start;
     }
     const node = this.startNode();

packages/babel-parser/src/parser/lval.js

@@ -1,5 +1,6 @@
 // @flow
 
+import * as charCodes from "charcodes";
 import { types as tt, type TokenType } from "../tokenizer/types";
 import type {
   TSParameterProperty,
@@ -60,6 +61,14 @@ export default class LValParser extends NodeUtils {
             const prop = node.properties[i];
             const isLast = i === last;
             this.toAssignableObjectExpressionProp(prop, isBinding, isLast);
+
+            if (
+              isLast &&
+              prop.type === "RestElement" &&
+              node.extra?.trailingComma
+            ) {
+              this.raiseRestNotLast(node.extra.trailingComma);
+            }
           }
           break;
 
@@ -78,7 +87,12 @@ export default class LValParser extends NodeUtils {
 
         case "ArrayExpression":
           node.type = "ArrayPattern";
-          this.toAssignableList(node.elements, isBinding, contextDescription);
+          this.toAssignableList(
+            node.elements,
+            isBinding,
+            contextDescription,
+            node.extra?.trailingComma,
+          );
           break;
 
         case "AssignmentExpression":
@@ -142,6 +156,7 @@ export default class LValParser extends NodeUtils {
     exprList: Expression[],
     isBinding: ?boolean,
     contextDescription: string,
+    trailingCommaPos?: ?number,
   ): $ReadOnlyArray<Pattern> {
     let end = exprList.length;
     if (end) {
@@ -160,6 +175,11 @@ export default class LValParser extends NodeUtils {
         ) {
           this.unexpected(arg.start);
         }
+
+        if (trailingCommaPos) {
+          this.raiseTrailingCommaAfterRest(trailingCommaPos);
+        }
+
         --end;
       }
     }
@@ -213,11 +233,6 @@ export default class LValParser extends NodeUtils {
       undefined,
       refNeedsArrowPos,
     );
-
-    if (this.state.commaAfterSpreadAt === -1 && this.match(tt.comma)) {
-      this.state.commaAfterSpreadAt = this.state.start;
-    }
-
     return this.finishNode(node, "SpreadElement");
   }
 
@@ -234,7 +249,11 @@ export default class LValParser extends NodeUtils {
       case tt.bracketL: {
         const node = this.startNode();
         this.next();
-        node.elements = this.parseBindingList(tt.bracketR, true);
+        node.elements = this.parseBindingList(
+          tt.bracketR,
+          charCodes.rightSquareBracket,
+          true,
+        );
         return this.finishNode(node, "ArrayPattern");
       }
 
@@ -247,6 +266,7 @@ export default class LValParser extends NodeUtils {
 
   parseBindingList(
     close: TokenType,
+    closeCharCode: $Values<typeof charCodes>,
     allowEmpty?: boolean,
     allowModifiers?: boolean,
   ): $ReadOnlyArray<Pattern | TSParameterProperty> {
@@ -265,7 +285,7 @@ export default class LValParser extends NodeUtils {
         break;
       } else if (this.match(tt.ellipsis)) {
         elts.push(this.parseAssignableListItemTypes(this.parseRestBinding()));
-        this.checkCommaAfterRest();
+        this.checkCommaAfterRest(closeCharCode);
         this.expect(close);
         break;
       } else {
@@ -455,19 +475,21 @@ export default class LValParser extends NodeUtils {
     }
   }
 
-  checkCommaAfterRest(): void {
+  checkCommaAfterRest(close: $Values<typeof charCodes>): void {
     if (this.match(tt.comma)) {
-      this.raiseRestNotLast(this.state.start);
-    }
-  }
-
-  checkCommaAfterRestFromSpread(): void {
-    if (this.state.commaAfterSpreadAt > -1) {
-      this.raiseRestNotLast(this.state.commaAfterSpreadAt);
+      if (this.lookaheadCharCode() === close) {
+        this.raiseTrailingCommaAfterRest(this.state.start);
+      } else {
+        this.raiseRestNotLast(this.state.start);
+      }
     }
   }
 
   raiseRestNotLast(pos: number) {
     this.raise(pos, `Rest element must be last element`);
   }
+
+  raiseTrailingCommaAfterRest(pos: number) {
+    this.raise(pos, `Unexpected trailing comma after rest element`);
+  }
 }

packages/babel-parser/src/parser/statement.js

@@ -8,7 +8,7 @@ import {
   isIdentifierStart,
   keywordRelationalOperator,
 } from "../util/identifier";
-import { lineBreak, skipWhiteSpace } from "../util/whitespace";
+import { lineBreak } from "../util/whitespace";
 import * as charCodes from "charcodes";
 import {
   BIND_CLASS,
@@ -105,10 +105,7 @@ export default class StatementParser extends ExpressionParser {
     if (!this.isContextual("let")) {
       return false;
     }
-    skipWhiteSpace.lastIndex = this.state.pos;
-    const skip = skipWhiteSpace.exec(this.input);
-    // $FlowIgnore
-    const next = this.state.pos + skip[0].length;
+    const next = this.nextTokenStart();
     const nextCh = this.input.charCodeAt(next);
     // For ambiguous cases, determine if a LexicalDeclaration (or only a
     // Statement) is allowed here. If context is not empty then only a Statement
@@ -170,7 +167,7 @@ export default class StatementParser extends ExpressionParser {
       case tt._for:
         return this.parseForStatement(node);
       case tt._function:
-        if (this.lookahead().type === tt.dot) break;
+        if (this.lookaheadCharCode() === charCodes.dot) break;
         if (context) {
           if (this.state.strict) {
             this.raise(
@@ -223,8 +220,11 @@ export default class StatementParser extends ExpressionParser {
         return this.parseEmptyStatement(node);
       case tt._export:
       case tt._import: {
-        const nextToken = this.lookahead();
-        if (nextToken.type === tt.parenL || nextToken.type === tt.dot) {
+        const nextTokenCharCode = this.lookaheadCharCode();
+        if (
+          nextTokenCharCode === charCodes.leftParenthesis ||
+          nextTokenCharCode === charCodes.dot
+        ) {
           break;
         }
 
@@ -1050,12 +1050,14 @@ export default class StatementParser extends ExpressionParser {
       node.id = this.parseFunctionId(requireId);
     }
 
+    const oldMaybeInArrowParameters = this.state.maybeInArrowParameters;
     const oldInClassProperty = this.state.inClassProperty;
     const oldYieldPos = this.state.yieldPos;
     const oldAwaitPos = this.state.awaitPos;
+    this.state.maybeInArrowParameters = false;
     this.state.inClassProperty = false;
-    this.state.yieldPos = 0;
-    this.state.awaitPos = 0;
+    this.state.yieldPos = -1;
+    this.state.awaitPos = -1;
     this.scope.enter(functionFlags(node.async, node.generator));
 
     if (!isStatement) {
@@ -1084,6 +1086,7 @@ export default class StatementParser extends ExpressionParser {
       this.checkFunctionStatementId(node);
     }
 
+    this.state.maybeInArrowParameters = oldMaybeInArrowParameters;
     this.state.inClassProperty = oldInClassProperty;
     this.state.yieldPos = oldYieldPos;
     this.state.awaitPos = oldAwaitPos;
@@ -1102,6 +1105,7 @@ export default class StatementParser extends ExpressionParser {
     this.expect(tt.parenL);
     node.params = this.parseBindingList(
       tt.parenR,
+      charCodes.rightParenthesis,
       /* allowEmpty */ false,
       allowModifiers,
     );
@@ -1498,13 +1502,18 @@ export default class StatementParser extends ExpressionParser {
   }
 
   pushClassProperty(classBody: N.ClassBody, prop: N.ClassProperty) {
-    // This only affects properties, not methods.
-    if (this.isNonstaticConstructor(prop)) {
+    if (
+      !prop.computed &&
+      (prop.key.name === "constructor" || prop.key.value === "constructor")
+    ) {
+      // Non-computed field, which is either an identifier named "constructor"
+      // or a string literal named "constructor"
       this.raise(
         prop.key.start,
-        "Classes may not have a non-static field named 'constructor'",
+        "Classes may not have a field named 'constructor'",
       );
     }
+
     classBody.body.push(this.parseClassProperty(prop));
   }
 
@@ -1738,11 +1747,11 @@ export default class StatementParser extends ExpressionParser {
   maybeParseExportDeclaration(node: N.Node): boolean {
     if (this.shouldParseExportDeclaration()) {
       if (this.isContextual("async")) {
-        const next = this.lookahead();
+        const next = this.nextTokenStart();
 
         // export async;
-        if (next.type !== tt._function) {
-          this.unexpected(next.start, `Unexpected token, expected "function"`);
+        if (!this.isUnparsedContextual(next, "function")) {
+          this.unexpected(next, `Unexpected token, expected "function"`);
         }
       }
 
@@ -1757,21 +1766,10 @@ export default class StatementParser extends ExpressionParser {
 
   isAsyncFunction(): boolean {
     if (!this.isContextual("async")) return false;
-
-    const { pos } = this.state;
-
-    skipWhiteSpace.lastIndex = pos;
-    const skip = skipWhiteSpace.exec(this.input);
-
-    if (!skip || !skip.length) return false;
-
-    const next = pos + skip[0].length;
-
+    const next = this.nextTokenStart();
     return (
-      !lineBreak.test(this.input.slice(pos, next)) &&
-      this.input.slice(next, next + 8) === "function" &&
-      (next + 8 === this.length ||
-        !isIdentifierChar(this.input.charCodeAt(next + 8)))
+      !lineBreak.test(this.input.slice(this.state.pos, next)) &&
+      this.isUnparsedContextual(next, "function")
     );
   }
 
@@ -1833,10 +1831,10 @@ export default class StatementParser extends ExpressionParser {
       return false;
     }
 
-    const lookahead = this.lookahead();
+    const next = this.nextTokenStart();
     return (
-      lookahead.type === tt.comma ||
-      (lookahead.type === tt.name && lookahead.value === "from")
+      this.input.charCodeAt(next) === charCodes.comma ||
+      this.isUnparsedContextual(next, "from")
     );
   }
 

packages/babel-parser/src/parser/util.js

@@ -4,6 +4,8 @@ import { types as tt, type TokenType } from "../tokenizer/types";
 import Tokenizer from "../tokenizer";
 import type { Node } from "../types";
 import { lineBreak, skipWhiteSpace } from "../util/whitespace";
+import { isIdentifierChar } from "../util/identifier";
+import * as charCodes from "charcodes";
 
 const literal = /^('|")((?:\\?.)*?)\1/;
 
@@ -26,8 +28,15 @@ export default class UtilParser extends Tokenizer {
   }
 
   isLookaheadRelational(op: "<" | ">"): boolean {
-    const l = this.lookahead();
-    return l.type === tt.relational && l.value === op;
+    const next = this.nextTokenStart();
+    if (this.input.charAt(next) === op) {
+      if (next + 1 === this.input.length) {
+        return true;
+      }
+      const afterNext = this.input.charCodeAt(next + 1);
+      return afterNext !== op.charCodeAt(0) && afterNext !== charCodes.equalsTo;
+    }
+    return false;
   }
 
   // TODO
@@ -60,9 +69,18 @@ export default class UtilParser extends Tokenizer {
     );
   }
 
+  isUnparsedContextual(nameStart: number, name: string): boolean {
+    const nameEnd = nameStart + name.length;
+    return (
+      this.input.slice(nameStart, nameEnd) === name &&
+      (nameEnd === this.input.length ||
+        !isIdentifierChar(this.input.charCodeAt(nameEnd)))
+    );
+  }
+
   isLookaheadContextual(name: string): boolean {
-    const l = this.lookahead();
-    return l.type === tt.name && l.value === name;
+    const next = this.nextTokenStart();
+    return this.isUnparsedContextual(next, name);
   }
 
   // Consumes contextual keyword if possible.
@@ -159,15 +177,15 @@ export default class UtilParser extends Tokenizer {
 
   checkYieldAwaitInDefaultParams() {
     if (
-      this.state.yieldPos &&
-      (!this.state.awaitPos || this.state.yieldPos < this.state.awaitPos)
+      this.state.yieldPos !== -1 &&
+      (this.state.awaitPos === -1 || this.state.yieldPos < this.state.awaitPos)
     ) {
       this.raise(
         this.state.yieldPos,
         "Yield cannot be used as name inside a generator function",
       );
     }
-    if (this.state.awaitPos) {
+    if (this.state.awaitPos !== -1) {
       this.raise(
         this.state.awaitPos,
         "Await cannot be used as name inside an async function",

packages/babel-parser/src/plugins/flow.js

@@ -14,6 +14,8 @@ import {
   type BindingTypes,
   BIND_NONE,
   BIND_LEXICAL,
+  BIND_VAR,
+  BIND_FUNCTION,
   SCOPE_ARROW,
   SCOPE_OTHER,
 } from "../util/scopeflags";
@@ -270,6 +272,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       node.id = this.flowParseTypeAnnotatableIdentifier(
         /*allowPrimitiveOverride*/ true,
       );
+      this.scope.declareName(node.id.name, BIND_VAR, node.id.start);
       this.semicolon();
       return this.finishNode(node, "DeclareVariable");
     }
@@ -462,6 +465,12 @@ export default (superClass: Class<Parser>): Class<Parser> =>
     ): void {
       node.id = this.flowParseRestrictedIdentifier(/*liberal*/ !isClass);
 
+      this.scope.declareName(
+        node.id.name,
+        isClass ? BIND_FUNCTION : BIND_LEXICAL,
+        node.id.start,
+      );
+
       if (this.isRelational("<")) {
         node.typeParameters = this.flowParseTypeParameterDeclaration();
       } else {
@@ -1789,6 +1798,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
               ((node.params: any): N.Expression[]),
               true,
               "arrow function parameters",
+              node.extra?.trailingComma,
             );
             // Enter scope, as checkParams defines bindings
             this.scope.enter(functionFlags(false, false) | SCOPE_ARROW);
@@ -1811,6 +1821,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
             ((node.params: any): N.Expression[]),
             true,
             "arrow function parameters",
+            node.extra?.trailingComma,
           );
         }
         return [arrows, []];
@@ -1822,6 +1833,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
             ((node.params: any): N.Expression[]),
             true,
             "arrow function parameters",
+            node.extra?.trailingComma,
           );
           return true;
         } catch (err) {
@@ -1996,6 +2008,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       exprList: N.Expression[],
       isBinding: ?boolean,
       contextDescription: string,
+      trailingCommaPos?: ?number,
     ): $ReadOnlyArray<N.Pattern> {
       for (let i = 0; i < exprList.length; i++) {
         const expr = exprList[i];
@@ -2003,7 +2016,12 @@ export default (superClass: Class<Parser>): Class<Parser> =>
           exprList[i] = this.typeCastToParameter(expr);
         }
       }
-      return super.toAssignableList(exprList, isBinding, contextDescription);
+      return super.toAssignableList(
+        exprList,
+        isBinding,
+        contextDescription,
+        trailingCommaPos,
+      );
     }
 
     // this is a list of nodes, from something like a call expression, we need to filter the
@@ -2634,7 +2652,6 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       startLoc: Position,
       noCalls: ?boolean,
       subscriptState: N.ParseSubscriptState,
-      maybeAsyncArrow: boolean,
     ): N.Expression {
       if (this.match(tt.questionDot) && this.isLookaheadRelational("<")) {
         this.expectPlugin("optionalChaining");
@@ -2687,7 +2704,6 @@ export default (superClass: Class<Parser>): Class<Parser> =>
         startLoc,
         noCalls,
         subscriptState,
-        maybeAsyncArrow,
       );
     }
 

packages/babel-parser/src/plugins/typescript/index.js

@@ -9,6 +9,7 @@ import type Parser from "../../parser";
 import {
   type BindingTypes,
   BIND_NONE,
+  SCOPE_TS_MODULE,
   SCOPE_OTHER,
   BIND_TS_ENUM,
   BIND_TS_CONST_ENUM,
@@ -19,6 +20,7 @@ import {
   BIND_CLASS,
 } from "../../util/scopeflags";
 import TypeScriptScopeHandler from "./scope";
+import * as charCodes from "charcodes";
 
 type TsModifier =
   | "readonly"
@@ -361,21 +363,23 @@ export default (superClass: Class<Parser>): Class<Parser> =>
     tsParseBindingListForSignature(): $ReadOnlyArray<
       N.Identifier | N.RestElement | N.ObjectPattern | N.ArrayPattern,
     > {
-      return this.parseBindingList(tt.parenR).map(pattern => {
-        if (
-          pattern.type !== "Identifier" &&
-          pattern.type !== "RestElement" &&
-          pattern.type !== "ObjectPattern" &&
-          pattern.type !== "ArrayPattern"
-        ) {
-          throw this.unexpected(
-            pattern.start,
-            "Name in a signature must be an Identifier, ObjectPattern or ArrayPattern," +
-              `instead got ${pattern.type}`,
-          );
-        }
-        return pattern;
-      });
+      return this.parseBindingList(tt.parenR, charCodes.rightParenthesis).map(
+        pattern => {
+          if (
+            pattern.type !== "Identifier" &&
+            pattern.type !== "RestElement" &&
+            pattern.type !== "ObjectPattern" &&
+            pattern.type !== "ArrayPattern"
+          ) {
+            throw this.unexpected(
+              pattern.start,
+              "Name in a signature must be an Identifier, ObjectPattern or ArrayPattern," +
+                `instead got ${pattern.type}`,
+            );
+          }
+          return pattern;
+        },
+      );
     }
 
     tsParseTypeMemberSemicolon(): void {
@@ -584,7 +588,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
         const restNode: N.TsRestType = this.startNode();
         this.next(); // skips ellipsis
         restNode.typeAnnotation = this.tsParseType();
-        this.checkCommaAfterRest();
+        this.checkCommaAfterRest(charCodes.rightSquareBracket);
         return this.finishNode(restNode, "TSRestType");
       }
 
@@ -657,7 +661,10 @@ export default (superClass: Class<Parser>): Class<Parser> =>
             : this.match(tt._null)
             ? "TSNullKeyword"
             : keywordTypeFromName(this.state.value);
-          if (type !== undefined && this.lookahead().type !== tt.dot) {
+          if (
+            type !== undefined &&
+            this.lookaheadCharCode() !== charCodes.dot
+          ) {
             const node: N.TsKeywordType = this.startNode();
             this.next();
             return this.finishNode(node, type);
@@ -1163,7 +1170,9 @@ export default (superClass: Class<Parser>): Class<Parser> =>
         this.tsParseModuleOrNamespaceDeclaration(inner, true);
         node.body = inner;
       } else {
+        this.scope.enter(SCOPE_TS_MODULE);
         node.body = this.tsParseModuleBlock();
+        this.scope.exit();
       }
       return this.finishNode(node, "TSModuleDeclaration");
     }
@@ -1179,9 +1188,10 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       } else {
         this.unexpected();
       }
-
       if (this.match(tt.braceL)) {
+        this.scope.enter(SCOPE_TS_MODULE);
         node.body = this.tsParseModuleBlock();
+        this.scope.exit();
       } else {
         this.semicolon();
       }
@@ -1203,7 +1213,8 @@ export default (superClass: Class<Parser>): Class<Parser> =>
 
     tsIsExternalModuleReference(): boolean {
       return (
-        this.isContextual("require") && this.lookahead().type === tt.parenL
+        this.isContextual("require") &&
+        this.lookaheadCharCode() === charCodes.leftParenthesis
       );
     }
 
@@ -1332,10 +1343,12 @@ export default (superClass: Class<Parser>): Class<Parser> =>
           // `global { }` (with no `declare`) may appear inside an ambient module declaration.
           // Would like to use tsParseAmbientExternalModuleDeclaration here, but already ran past "global".
           if (this.match(tt.braceL)) {
+            this.scope.enter(SCOPE_TS_MODULE);
             const mod: N.TsModuleDeclaration = node;
             mod.global = true;
             mod.id = expr;
             mod.body = this.tsParseModuleBlock();
+            this.scope.exit();
             return this.finishNode(mod, "TSModuleDeclaration");
           }
           break;
@@ -1568,7 +1581,6 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       startLoc: Position,
       noCalls: ?boolean,
       state: N.ParseSubscriptState,
-      maybeAsyncArrow: boolean,
     ): N.Expression {
       if (!this.hasPrecedingLineBreak() && this.match(tt.bang)) {
         this.state.exprAllowed = false;
@@ -1631,14 +1643,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
         if (result) return result;
       }
 
-      return super.parseSubscript(
-        base,
-        startPos,
-        startLoc,
-        noCalls,
-        state,
-        maybeAsyncArrow,
-      );
+      return super.parseSubscript(base, startPos, startLoc, noCalls, state);
     }
 
     parseNewArguments(node: N.NewExpression): void {
@@ -2360,11 +2365,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       }
     }
 
-    toAssignableList(
-      exprList: N.Expression[],
-      isBinding: ?boolean,
-      contextDescription: string,
-    ): $ReadOnlyArray<N.Pattern> {
+    toAssignableList(exprList: N.Expression[]): $ReadOnlyArray<N.Pattern> {
       for (let i = 0; i < exprList.length; i++) {
         const expr = exprList[i];
         if (!expr) continue;
@@ -2381,7 +2382,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
             break;
         }
       }
-      return super.toAssignableList(exprList, isBinding, contextDescription);
+      return super.toAssignableList(...arguments);
     }
 
     typeCastToParameter(node: N.TsTypeCastExpression): N.Node {

packages/babel-parser/src/tokenizer/index.js

@@ -13,6 +13,7 @@ import {
   lineBreakG,
   isNewLine,
   isWhitespace,
+  skipWhiteSpace,
 } from "../util/whitespace";
 import State from "./state";
 
@@ -168,6 +169,18 @@ export default class Tokenizer extends LocationParser {
     return curr;
   }
 
+  nextTokenStart(): number {
+    const thisTokEnd = this.state.pos;
+    skipWhiteSpace.lastIndex = thisTokEnd;
+    const skip = skipWhiteSpace.exec(this.input);
+    // $FlowIgnore: The skipWhiteSpace ensures to match any string
+    return thisTokEnd + skip[0].length;
+  }
+
+  lookaheadCharCode(): number {
+    return this.input.charCodeAt(this.nextTokenStart());
+  }
+
   // Toggle strict mode. Re-reads the next number or string to please
   // pedantic tests (`"use strict"; 010;` should fail).
 
@@ -234,8 +247,8 @@ export default class Tokenizer extends LocationParser {
   skipBlockComment(): void {
     const startLoc = this.state.curPosition();
     const start = this.state.pos;
-    const end = this.input.indexOf("*/", (this.state.pos += 2));
-    if (end === -1) this.raise(this.state.pos - 2, "Unterminated comment");
+    const end = this.input.indexOf("*/", this.state.pos + 2);
+    if (end === -1) this.raise(start, "Unterminated comment");
 
     this.state.pos = end + 2;
     lineBreakG.lastIndex = start;
@@ -267,13 +280,7 @@ export default class Tokenizer extends LocationParser {
     const startLoc = this.state.curPosition();
     let ch = this.input.charCodeAt((this.state.pos += startSkip));
     if (this.state.pos < this.length) {
-      while (
-        ch !== charCodes.lineFeed &&
-        ch !== charCodes.carriageReturn &&
-        ch !== charCodes.lineSeparator &&
-        ch !== charCodes.paragraphSeparator &&
-        ++this.state.pos < this.length
-      ) {
+      while (!isNewLine(ch) && ++this.state.pos < this.length) {
         ch = this.input.charCodeAt(this.state.pos);
       }
     }
@@ -404,8 +411,10 @@ export default class Tokenizer extends LocationParser {
       return;
     }
 
-    const next2 = this.input.charCodeAt(this.state.pos + 2);
-    if (next === charCodes.dot && next2 === charCodes.dot) {
+    if (
+      next === charCodes.dot &&
+      this.input.charCodeAt(this.state.pos + 2) === charCodes.dot
+    ) {
       this.state.pos += 3;
       this.finishToken(tt.ellipsis);
     } else {
@@ -439,13 +448,7 @@ export default class Tokenizer extends LocationParser {
     let ch = this.input.charCodeAt(this.state.pos);
     if (ch !== charCodes.exclamationMark) return false;
 
-    while (
-      ch !== charCodes.lineFeed &&
-      ch !== charCodes.carriageReturn &&
-      ch !== charCodes.lineSeparator &&
-      ch !== charCodes.paragraphSeparator &&
-      ++this.state.pos < this.length
-    ) {
+    while (!isNewLine(ch) && ++this.state.pos < this.length) {
       ch = this.input.charCodeAt(this.state.pos);
     }
 
@@ -878,7 +881,11 @@ export default class Tokenizer extends LocationParser {
   // were read, the integer value otherwise. When `len` is given, this
   // will return `null` unless the integer has exactly `len` digits.
 
-  readInt(radix: number, len?: number): number | null {
+  readInt(
+    radix: number,
+    len?: number,
+    allowNumSeparator: boolean = true,
+  ): number | null {
     const start = this.state.pos;
     const forbiddenSiblings =
       radix === 16
@@ -900,9 +907,9 @@ export default class Tokenizer extends LocationParser {
       let val;
 
       if (this.hasPlugin("numericSeparator")) {
-        const prev = this.input.charCodeAt(this.state.pos - 1);
-        const next = this.input.charCodeAt(this.state.pos + 1);
         if (code === charCodes.underscore) {
+          const prev = this.input.charCodeAt(this.state.pos - 1);
+          const next = this.input.charCodeAt(this.state.pos + 1);
           if (allowedSiblings.indexOf(next) === -1) {
             this.raise(this.state.pos, "Invalid or unexpected token");
           }
@@ -915,6 +922,13 @@ export default class Tokenizer extends LocationParser {
             this.raise(this.state.pos, "Invalid or unexpected token");
           }
 
+          if (!allowNumSeparator) {
+            this.raise(
+              this.state.pos,
+              "Numeric separators are not allowed inside unicode escape sequences or hex escape sequences",
+            );
+          }
+
           // Ignore this _ character
           ++this.state.pos;
           continue;
@@ -980,6 +994,7 @@ export default class Tokenizer extends LocationParser {
     const start = this.state.pos;
     let isFloat = false;
     let isBigInt = false;
+    let isNonOctalDecimalInt = false;
 
     if (!startsWithDot && this.readInt(10) === null) {
       this.raise(start, "Invalid number");
@@ -996,6 +1011,7 @@ export default class Tokenizer extends LocationParser {
       }
       if (/[89]/.test(this.input.slice(start, this.state.pos))) {
         octal = false;
+        isNonOctalDecimalInt = true;
       }
     }
 
@@ -1020,10 +1036,26 @@ export default class Tokenizer extends LocationParser {
       next = this.input.charCodeAt(this.state.pos);
     }
 
+    // disallow numeric separators in non octal decimals and legacy octal likes
+    if (this.hasPlugin("numericSeparator") && (octal || isNonOctalDecimalInt)) {
+      const underscorePos = this.input
+        .slice(start, this.state.pos)
+        .indexOf("_");
+      if (underscorePos > 0) {
+        this.raise(
+          underscorePos + start,
+          "Numeric separator can not be used after leading 0",
+        );
+      }
+    }
+
     if (this.hasPlugin("bigInt")) {
       if (next === charCodes.lowercaseN) {
-        // disallow floats and legacy octal syntax, new style octal ("0o") is handled in this.readRadixNumber
-        if (isFloat || octal) this.raise(start, "Invalid BigIntLiteral");
+        // disallow floats, legacy octal syntax and non octal decimals
+        // new style octal ("0o") is handled in this.readRadixNumber
+        if (isFloat || octal || isNonOctalDecimalInt) {
+          this.raise(start, "Invalid BigIntLiteral");
+        }
         ++this.state.pos;
         isBigInt = true;
       }
@@ -1250,7 +1282,7 @@ export default class Tokenizer extends LocationParser {
 
   readHexChar(len: number, throwOnInvalid: boolean): number | null {
     const codePos = this.state.pos;
-    const n = this.readInt(16, len);
+    const n = this.readInt(16, len, false);
     if (n === null) {
       if (throwOnInvalid) {
         this.raise(codePos, "Bad character escape sequence");
@@ -1324,11 +1356,7 @@ export default class Tokenizer extends LocationParser {
 
   readWord(): void {
     const word = this.readWord1();
-    const type = keywordTypes.get(word) || tt.name;
-
-    if (type.keyword && this.state.containsEsc) {
-      this.raise(this.state.pos, `Escape sequence in keyword ${word}`);
-    }
+    const type = (!this.state.containsEsc && keywordTypes.get(word)) || tt.name;
 
     // Allow @@iterator and @@asyncIterator as a identifier only inside type
     if (

packages/babel-parser/src/tokenizer/state.js

@@ -55,11 +55,6 @@ export default class State {
   //          ^
   noArrowParamsConversionAt: number[] = [];
 
-  // A comma after "...a" is only allowed in spread, but not in rest.
-  // Since we parse destructuring patterns as array/object literals
-  // and then convert them, we need to track it.
-  commaAfterSpreadAt: number = -1;
-
   // Flags to track
   inParameters: boolean = false;
   maybeInArrowParameters: boolean = false;
@@ -97,8 +92,8 @@ export default class State {
   decoratorStack: Array<Array<N.Decorator>> = [[]];
 
   // Positions to delayed-check that yield/await does not exist in default parameters.
-  yieldPos: number = 0;
-  awaitPos: number = 0;
+  yieldPos: number = -1;
+  awaitPos: number = -1;
 
   // Token store.
   tokens: Array<Token | N.Comment> = [];

packages/babel-parser/src/types.js

@@ -1447,5 +1447,6 @@ export type Placeholder<N: PlaceholderTypes> = NodeBase & {
 
 export type ParseSubscriptState = {
   optionalChainMember: boolean,
+  maybeAsyncArrow: boolean,
   stop: boolean,
 };

packages/babel-parser/src/util/scopeflags.js

@@ -2,17 +2,18 @@
 
 // Each scope gets a bitset that may contain these flags
 // prettier-ignore
-export const SCOPE_OTHER        = 0b000000000,
-             SCOPE_PROGRAM      = 0b000000001,
-             SCOPE_FUNCTION     = 0b000000010,
-             SCOPE_ASYNC        = 0b000000100,
-             SCOPE_GENERATOR    = 0b000001000,
-             SCOPE_ARROW        = 0b000010000,
-             SCOPE_SIMPLE_CATCH = 0b000100000,
-             SCOPE_SUPER        = 0b001000000,
-             SCOPE_DIRECT_SUPER = 0b010000000,
-             SCOPE_CLASS        = 0b100000000,
-             SCOPE_VAR = SCOPE_PROGRAM | SCOPE_FUNCTION;
+export const SCOPE_OTHER        = 0b0000000000,
+             SCOPE_PROGRAM      = 0b0000000001,
+             SCOPE_FUNCTION     = 0b0000000010,
+             SCOPE_ASYNC        = 0b0000000100,
+             SCOPE_GENERATOR    = 0b0000001000,
+             SCOPE_ARROW        = 0b0000010000,
+             SCOPE_SIMPLE_CATCH = 0b0000100000,
+             SCOPE_SUPER        = 0b0001000000,
+             SCOPE_DIRECT_SUPER = 0b0010000000,
+             SCOPE_CLASS        = 0b0100000000,
+             SCOPE_TS_MODULE    = 0b1000000000,
+             SCOPE_VAR = SCOPE_PROGRAM | SCOPE_FUNCTION | SCOPE_TS_MODULE;
 
 export type ScopeFlags =
   | typeof SCOPE_OTHER

packages/babel-parser/test/fixtures/comments/basic/array-expression-trailing-comma/output.json

@@ -373,7 +373,10 @@
                     }
                   ]
                 }
-              ]
+              ],
+              "extra": {
+                "trailingComma": 140
+              }
             }
           }
         ],
@@ -494,7 +497,10 @@
                     }
                   ]
                 }
-              ]
+              ],
+              "extra": {
+                "trailingComma": 200
+              }
             }
           }
         ],

packages/babel-parser/test/fixtures/comments/basic/function-trailing-comma-shorthand/output.json

@@ -74,6 +74,9 @@
             },
             "name": "fn"
           },
+          "extra": {
+            "trailingComma": 11
+          },
           "arguments": [
             {
               "type": "Identifier",

packages/babel-parser/test/fixtures/comments/basic/function-trailing-comma/output.json

@@ -74,6 +74,9 @@
             },
             "name": "fn"
           },
+          "extra": {
+            "trailingComma": 7
+          },
           "arguments": [
             {
               "type": "Identifier",

packages/babel-parser/test/fixtures/comments/basic/object-expression-trailing-comma/output.json

@@ -181,6 +181,9 @@
                   }
                 }
               ],
+              "extra": {
+                "trailingComma": 35
+              },
               "trailingComments": [
                 {
                   "type": "CommentBlock",

packages/babel-parser/test/fixtures/comments/basic/object-property-trailing-comma/output.json

@@ -309,7 +309,10 @@
                     }
                   ]
                 }
-              ]
+              ],
+              "extra": {
+                "trailingComma": 66
+              }
             }
           }
         ],

packages/babel-parser/test/fixtures/comments/basic/switch-function-call-no-semicolon/output.json

@@ -250,7 +250,25 @@
                 "label": null
               }
             ],
-            "test": null
+            "test": null,
+            "leadingComments": [
+              {
+                "type": "CommentLine",
+                "value": " comment",
+                "start": 47,
+                "end": 57,
+                "loc": {
+                  "start": {
+                    "line": 4,
+                    "column": 4
+                  },
+                  "end": {
+                    "line": 4,
+                    "column": 14
+                  }
+                }
+              }
+            ]
           }
         ]
       }

packages/babel-parser/test/fixtures/comments/regression/10230/output.json

@@ -163,7 +163,10 @@
                   }
                 ]
               }
-            ]
+            ],
+            "extra": {
+              "trailingComma": 13
+            }
           }
         },
         "trailingComments": [
@@ -215,7 +218,25 @@
             "identifierName": "B"
           },
           "name": "B"
-        }
+        },
+        "leadingComments": [
+          {
+            "type": "CommentLine",
+            "value": " Two",
+            "start": 27,
+            "end": 33,
+            "loc": {
+              "start": {
+                "line": 6,
+                "column": 0
+              },
+              "end": {
+                "line": 6,
+                "column": 6
+              }
+            }
+          }
+        ]
       }
     ],
     "directives": []

packages/babel-parser/test/fixtures/comments/regression/10432/input.js

@@ -0,0 +1,5 @@
+const socket = socketClient(address)
+/* istanbul ignore next */
+socket.on('connect', function () {
+  debug('Connected to ' + address)
+})

packages/babel-parser/test/fixtures/comments/regression/10432/output.json

@@ -0,0 +1,431 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 136,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 5,
+      "column": 2
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 136,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 5,
+        "column": 2
+      }
+    },
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "VariableDeclaration",
+        "start": 0,
+        "end": 36,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 36
+          }
+        },
+        "declarations": [
+          {
+            "type": "VariableDeclarator",
+            "start": 6,
+            "end": 36,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 6
+              },
+              "end": {
+                "line": 1,
+                "column": 36
+              }
+            },
+            "id": {
+              "type": "Identifier",
+              "start": 6,
+              "end": 12,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 6
+                },
+                "end": {
+                  "line": 1,
+                  "column": 12
+                },
+                "identifierName": "socket"
+              },
+              "name": "socket"
+            },
+            "init": {
+              "type": "CallExpression",
+              "start": 15,
+              "end": 36,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 15
+                },
+                "end": {
+                  "line": 1,
+                  "column": 36
+                }
+              },
+              "callee": {
+                "type": "Identifier",
+                "start": 15,
+                "end": 27,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 15
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 27
+                  },
+                  "identifierName": "socketClient"
+                },
+                "name": "socketClient"
+              },
+              "arguments": [
+                {
+                  "type": "Identifier",
+                  "start": 28,
+                  "end": 35,
+                  "loc": {
+                    "start": {
+                      "line": 1,
+                      "column": 28
+                    },
+                    "end": {
+                      "line": 1,
+                      "column": 35
+                    },
+                    "identifierName": "address"
+                  },
+                  "name": "address"
+                }
+              ]
+            }
+          }
+        ],
+        "kind": "const",
+        "trailingComments": [
+          {
+            "type": "CommentBlock",
+            "value": " istanbul ignore next ",
+            "start": 37,
+            "end": 63,
+            "loc": {
+              "start": {
+                "line": 2,
+                "column": 0
+              },
+              "end": {
+                "line": 2,
+                "column": 26
+              }
+            }
+          }
+        ]
+      },
+      {
+        "type": "ExpressionStatement",
+        "start": 64,
+        "end": 136,
+        "loc": {
+          "start": {
+            "line": 3,
+            "column": 0
+          },
+          "end": {
+            "line": 5,
+            "column": 2
+          }
+        },
+        "expression": {
+          "type": "CallExpression",
+          "start": 64,
+          "end": 136,
+          "loc": {
+            "start": {
+              "line": 3,
+              "column": 0
+            },
+            "end": {
+              "line": 5,
+              "column": 2
+            }
+          },
+          "callee": {
+            "type": "MemberExpression",
+            "start": 64,
+            "end": 73,
+            "loc": {
+              "start": {
+                "line": 3,
+                "column": 0
+              },
+              "end": {
+                "line": 3,
+                "column": 9
+              }
+            },
+            "object": {
+              "type": "Identifier",
+              "start": 64,
+              "end": 70,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 0
+                },
+                "end": {
+                  "line": 3,
+                  "column": 6
+                },
+                "identifierName": "socket"
+              },
+              "name": "socket"
+            },
+            "property": {
+              "type": "Identifier",
+              "start": 71,
+              "end": 73,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 7
+                },
+                "end": {
+                  "line": 3,
+                  "column": 9
+                },
+                "identifierName": "on"
+              },
+              "name": "on"
+            },
+            "computed": false
+          },
+          "arguments": [
+            {
+              "type": "StringLiteral",
+              "start": 74,
+              "end": 83,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 10
+                },
+                "end": {
+                  "line": 3,
+                  "column": 19
+                }
+              },
+              "extra": {
+                "rawValue": "connect",
+                "raw": "'connect'"
+              },
+              "value": "connect"
+            },
+            {
+              "type": "FunctionExpression",
+              "start": 85,
+              "end": 135,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 21
+                },
+                "end": {
+                  "line": 5,
+                  "column": 1
+                }
+              },
+              "id": null,
+              "generator": false,
+              "async": false,
+              "params": [],
+              "body": {
+                "type": "BlockStatement",
+                "start": 97,
+                "end": 135,
+                "loc": {
+                  "start": {
+                    "line": 3,
+                    "column": 33
+                  },
+                  "end": {
+                    "line": 5,
+                    "column": 1
+                  }
+                },
+                "body": [
+                  {
+                    "type": "ExpressionStatement",
+                    "start": 101,
+                    "end": 133,
+                    "loc": {
+                      "start": {
+                        "line": 4,
+                        "column": 2
+                      },
+                      "end": {
+                        "line": 4,
+                        "column": 34
+                      }
+                    },
+                    "expression": {
+                      "type": "CallExpression",
+                      "start": 101,
+                      "end": 133,
+                      "loc": {
+                        "start": {
+                          "line": 4,
+                          "column": 2
+                        },
+                        "end": {
+                          "line": 4,
+                          "column": 34
+                        }
+                      },
+                      "callee": {
+                        "type": "Identifier",
+                        "start": 101,
+                        "end": 106,
+                        "loc": {
+                          "start": {
+                            "line": 4,
+                            "column": 2
+                          },
+                          "end": {
+                            "line": 4,
+                            "column": 7
+                          },
+                          "identifierName": "debug"
+                        },
+                        "name": "debug"
+                      },
+                      "arguments": [
+                        {
+                          "type": "BinaryExpression",
+                          "start": 107,
+                          "end": 132,
+                          "loc": {
+                            "start": {
+                              "line": 4,
+                              "column": 8
+                            },
+                            "end": {
+                              "line": 4,
+                              "column": 33
+                            }
+                          },
+                          "left": {
+                            "type": "StringLiteral",
+                            "start": 107,
+                            "end": 122,
+                            "loc": {
+                              "start": {
+                                "line": 4,
+                                "column": 8
+                              },
+                              "end": {
+                                "line": 4,
+                                "column": 23
+                              }
+                            },
+                            "extra": {
+                              "rawValue": "Connected to ",
+                              "raw": "'Connected to '"
+                            },
+                            "value": "Connected to "
+                          },
+                          "operator": "+",
+                          "right": {
+                            "type": "Identifier",
+                            "start": 125,
+                            "end": 132,
+                            "loc": {
+                              "start": {
+                                "line": 4,
+                                "column": 26
+                              },
+                              "end": {
+                                "line": 4,
+                                "column": 33
+                              },
+                              "identifierName": "address"
+                            },
+                            "name": "address"
+                          }
+                        }
+                      ]
+                    }
+                  }
+                ],
+                "directives": []
+              }
+            }
+          ]
+        },
+        "leadingComments": [
+          {
+            "type": "CommentBlock",
+            "value": " istanbul ignore next ",
+            "start": 37,
+            "end": 63,
+            "loc": {
+              "start": {
+                "line": 2,
+                "column": 0
+              },
+              "end": {
+                "line": 2,
+                "column": 26
+              }
+            }
+          }
+        ]
+      }
+    ],
+    "directives": []
+  },
+  "comments": [
+    {
+      "type": "CommentBlock",
+      "value": " istanbul ignore next ",
+      "start": 37,
+      "end": 63,
+      "loc": {
+        "start": {
+          "line": 2,
+          "column": 0
+        },
+        "end": {
+          "line": 2,
+          "column": 26
+        }
+      }
+    }
+  ]
+}

packages/babel-parser/test/fixtures/comments/regression/10448/input.js

@@ -0,0 +1,2 @@
+function foo([foo, /* not used */, /* not used */]) {
+}

packages/babel-parser/test/fixtures/comments/regression/10448/output.json

@@ -0,0 +1,191 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 55,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 2,
+      "column": 1
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 55,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 2,
+        "column": 1
+      }
+    },
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "FunctionDeclaration",
+        "start": 0,
+        "end": 55,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 2,
+            "column": 1
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 9,
+          "end": 12,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 9
+            },
+            "end": {
+              "line": 1,
+              "column": 12
+            },
+            "identifierName": "foo"
+          },
+          "name": "foo"
+        },
+        "generator": false,
+        "async": false,
+        "params": [
+          {
+            "type": "ArrayPattern",
+            "start": 13,
+            "end": 50,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 13
+              },
+              "end": {
+                "line": 1,
+                "column": 50
+              }
+            },
+            "elements": [
+              {
+                "type": "Identifier",
+                "start": 14,
+                "end": 17,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 14
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 17
+                  },
+                  "identifierName": "foo"
+                },
+                "name": "foo",
+                "trailingComments": [
+                  {
+                    "type": "CommentBlock",
+                    "value": " not used ",
+                    "start": 19,
+                    "end": 33,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 19
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 33
+                      }
+                    }
+                  },
+                  {
+                    "type": "CommentBlock",
+                    "value": " not used ",
+                    "start": 35,
+                    "end": 49,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 35
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 49
+                      }
+                    }
+                  }
+                ]
+              },
+              null
+            ]
+          }
+        ],
+        "body": {
+          "type": "BlockStatement",
+          "start": 52,
+          "end": 55,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 52
+            },
+            "end": {
+              "line": 2,
+              "column": 1
+            }
+          },
+          "body": [],
+          "directives": []
+        }
+      }
+    ],
+    "directives": []
+  },
+  "comments": [
+    {
+      "type": "CommentBlock",
+      "value": " not used ",
+      "start": 19,
+      "end": 33,
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 19
+        },
+        "end": {
+          "line": 1,
+          "column": 33
+        }
+      }
+    },
+    {
+      "type": "CommentBlock",
+      "value": " not used ",
+      "start": 35,
+      "end": 49,
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 35
+        },
+        "end": {
+          "line": 1,
+          "column": 49
+        }
+      }
+    }
+  ]
+}

packages/babel-parser/test/fixtures/core/escape-keyword/invalid/input.js

@@ -0,0 +1,3 @@
+var a = {
+  br\u{65}ak
+};

packages/babel-parser/test/fixtures/core/escape-keyword/invalid/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Unexpected keyword 'break' (2:2)"
+}

packages/babel-parser/test/fixtures/core/escape-keyword/used-as-property/input.js

@@ -0,0 +1,3 @@
+var a = {
+  br\u{65}ak: 2
+};

packages/babel-parser/test/fixtures/core/escape-keyword/used-as-property/output.json

@@ -0,0 +1,157 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 28,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 3,
+      "column": 2
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 28,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 3,
+        "column": 2
+      }
+    },
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "VariableDeclaration",
+        "start": 0,
+        "end": 28,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 2
+          }
+        },
+        "declarations": [
+          {
+            "type": "VariableDeclarator",
+            "start": 4,
+            "end": 27,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 4
+              },
+              "end": {
+                "line": 3,
+                "column": 1
+              }
+            },
+            "id": {
+              "type": "Identifier",
+              "start": 4,
+              "end": 5,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 4
+                },
+                "end": {
+                  "line": 1,
+                  "column": 5
+                },
+                "identifierName": "a"
+              },
+              "name": "a"
+            },
+            "init": {
+              "type": "ObjectExpression",
+              "start": 8,
+              "end": 27,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 8
+                },
+                "end": {
+                  "line": 3,
+                  "column": 1
+                }
+              },
+              "properties": [
+                {
+                  "type": "ObjectProperty",
+                  "start": 12,
+                  "end": 25,
+                  "loc": {
+                    "start": {
+                      "line": 2,
+                      "column": 2
+                    },
+                    "end": {
+                      "line": 2,
+                      "column": 15
+                    }
+                  },
+                  "method": false,
+                  "key": {
+                    "type": "Identifier",
+                    "start": 12,
+                    "end": 22,
+                    "loc": {
+                      "start": {
+                        "line": 2,
+                        "column": 2
+                      },
+                      "end": {
+                        "line": 2,
+                        "column": 12
+                      },
+                      "identifierName": "break"
+                    },
+                    "name": "break"
+                  },
+                  "computed": false,
+                  "shorthand": false,
+                  "value": {
+                    "type": "NumericLiteral",
+                    "start": 24,
+                    "end": 25,
+                    "loc": {
+                      "start": {
+                        "line": 2,
+                        "column": 14
+                      },
+                      "end": {
+                        "line": 2,
+                        "column": 15
+                      }
+                    },
+                    "extra": {
+                      "rawValue": 2,
+                      "raw": "2"
+                    },
+                    "value": 2
+                  }
+                }
+              ]
+            }
+          }
+        ],
+        "kind": "var"
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/core/uncategorised/10/output.json

@@ -110,7 +110,10 @@
                 },
                 "value": 42
               }
-            ]
+            ],
+            "extra": {
+              "trailingComma": 8
+            }
           }
         }
       }

packages/babel-parser/test/fixtures/core/uncategorised/12/output.json

@@ -150,7 +150,10 @@
                 },
                 "value": 3
               }
-            ]
+            ],
+            "extra": {
+              "trailingComma": 13
+            }
           }
         }
       }

packages/babel-parser/test/fixtures/core/uncategorised/13/output.json

@@ -151,7 +151,10 @@
                 },
                 "value": 3
               }
-            ]
+            ],
+            "extra": {
+              "trailingComma": 14
+            }
           }
         }
       }

packages/babel-parser/test/fixtures/es2015/array-rest-spread/comma-after-rest/options.json

@@ -1,3 +1,3 @@
 {
-  "throws": "Rest element must be last element (1:5)"
+  "throws": "Unexpected trailing comma after rest element (1:5)"
 }

packages/babel-parser/test/fixtures/es2015/array-rest-spread/comma-after-spread-for-in/input.js

@@ -0,0 +1 @@
+for ([...a,] in []);

packages/babel-parser/test/fixtures/es2015/array-rest-spread/comma-after-spread-for-in/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Unexpected trailing comma after rest element (1:10)"
+}

packages/babel-parser/test/fixtures/es2015/array-rest-spread/comma-after-spread-nested/input.js

@@ -0,0 +1 @@
+[[...a,]] = [];

packages/babel-parser/test/fixtures/es2015/array-rest-spread/comma-after-spread-nested/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Unexpected trailing comma after rest element (1:6)"
+}