v7.6.3

* fix: should not remove let binding even it is wrapped in closure

Fixes #10339

* fix: remove bindings defined in blockScope when wrapped in closure

* Move test assertions to the top level to ensure that they run

.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/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 lockLabel: 'outdated'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

.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

@@ -17,6 +17,46 @@ 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 -->
+## v7.6.2 (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)
 

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 = ef7fd2bc27e7c10b4a71d2edc632a2934742a13e
+TEST262_COMMIT = 8688c4ab79059c3097098605e69f1ee5eda6c409
 
 # Fix color output until TravisCI fixes https://github.com/travis-ci/travis-ci/issues/7967
 export FORCE_COLOR = true
@@ -9,64 +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
+
+bootstrap-flowcheck: bootstrap-only
+	yarn gulp build-babel-types
+	$(MAKE) build-typings
+
+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:
-	./node_modules/.bin/eslint scripts $(SOURCES) '*.js' --format=codeframe
+	yarn eslint scripts $(SOURCES) '*.js' --format=codeframe
 
 lint-ts:
-	./scripts/tests/typescript/lint.sh
+	scripts/tests/typescript/lint.sh
 
-fix: fix-json
-	./node_modules/.bin/eslint scripts $(SOURCES) '*.js' --format=codeframe --fix
+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
@@ -79,72 +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-dist
+	$(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)", "")
@@ -153,23 +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
@@ -178,7 +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": "7.6.2",
+  "version": "7.6.3",
   "changelog": {
     "repo": "babel/babel",
     "cacheDir": ".changelog",

package.json

@@ -14,7 +14,9 @@
     "@babel/eslint-plugin-development": "^1.0.1",
     "@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-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",
@@ -22,7 +24,7 @@
     "@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",

packages/babel-cli/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/cli",
-  "version": "7.6.2",
+  "version": "7.6.3",
   "description": "Babel command line.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -27,7 +27,7 @@
     "mkdirp": "^0.5.1",
     "output-file-sync": "^2.0.0",
     "slash": "^2.0.0",
-    "source-map": "^0.5.0"
+    "source-map": "^0.6.1"
   },
   "optionalDependencies": {
     "chokidar": "^2.1.8"
@@ -36,8 +36,8 @@
     "@babel/core": "^7.0.0-0"
   },
   "devDependencies": {
-    "@babel/core": "^7.6.2",
-    "@babel/helper-fixtures": "^7.6.2"
+    "@babel/core": "^7.6.3",
+    "@babel/helper-fixtures": "^7.6.3"
   },
   "bin": {
     "babel": "./bin/babel.js",

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": "7.6.2",
+  "version": "7.6.3",
   "description": "Babel compiler core.",
   "main": "lib/index.js",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
@@ -34,21 +34,21 @@
   },
   "dependencies": {
     "@babel/code-frame": "^7.5.5",
-    "@babel/generator": "^7.6.2",
+    "@babel/generator": "^7.6.3",
     "@babel/helpers": "^7.6.2",
-    "@babel/parser": "^7.6.2",
+    "@babel/parser": "^7.6.3",
     "@babel/template": "^7.6.0",
-    "@babel/traverse": "^7.6.2",
-    "@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",
     "lodash": "^4.17.13",
     "resolve": "^1.3.2",
     "semver": "^5.4.1",
-    "source-map": "^0.5.0"
+    "source-map": "^0.6.1"
   },
   "devDependencies": {
-    "@babel/helper-transform-fixture-test-runner": "^7.6.0"
+    "@babel/helper-transform-fixture-test-runner": "^7.6.3"
   }
 }

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/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/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": "7.6.2",
+  "version": "7.6.3",
   "description": "Turns an AST into code.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -14,13 +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"
+    "source-map": "^0.6.1"
   },
   "devDependencies": {
-    "@babel/helper-fixtures": "^7.6.2",
-    "@babel/parser": "^7.6.2"
+    "@babel/helper-fixtures": "^7.6.3",
+    "@babel/parser": "^7.6.3"
   }
 }

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": "7.6.2",
+  "version": "7.6.3",
   "description": "Helper function to support fixtures",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "license": "MIT",

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

@@ -192,6 +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) {

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": "7.6.3",
   "description": "Transform test runner for @babel/helper-fixtures module",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -12,14 +12,14 @@
   "main": "lib/index.js",
   "dependencies": {
     "@babel/code-frame": "^7.5.5",
-    "@babel/core": "^7.6.0",
-    "@babel/helper-fixtures": "^7.6.0",
+    "@babel/core": "^7.6.3",
+    "@babel/helper-fixtures": "^7.6.3",
     "@babel/polyfill": "^7.6.0",
     "babel-check-duplicated-nodes": "^1.0.0",
     "jest": "^24.8.0",
     "jest-diff": "^24.8.0",
     "lodash": "^4.17.13",
     "resolve": "^1.3.2",
-    "source-map": "^0.5.0"
+    "source-map": "^0.6.1"
   }
 }

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-node/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/node",
-  "version": "7.6.2",
+  "version": "7.6.3",
   "description": "Babel command line",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -31,8 +31,8 @@
     "@babel/core": "^7.0.0-0"
   },
   "devDependencies": {
-    "@babel/core": "^7.6.2",
-    "@babel/helper-fixtures": "^7.6.2",
+    "@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/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/package.json

@@ -1,12 +1,12 @@
 {
   "name": "@babel/parser",
-  "version": "7.6.2",
+  "version": "7.6.3",
   "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": "^7.6.2",
+    "@babel/helper-fixtures": "^7.6.3",
     "charcodes": "^0.2.0",
     "unicode-12.0.0": "^0.7.9"
   },

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

@@ -40,7 +40,7 @@ export default class CommentsParser extends BaseParser {
 
   adjustCommentsAfterTrailingComma(
     node: Node,
-    elements: 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
@@ -55,12 +55,15 @@ export default class CommentsParser extends BaseParser {
       return;
     }
 
-    if (elements.length === 0) {
+    let lastElement = null;
+    let i = elements.length;
+    while (lastElement === null && i > 0) {
+      lastElement = elements[--i];
+    }
+    if (lastElement === null) {
       return;
     }
 
-    const lastElement = last(elements);
-
     for (let j = 0; j < this.state.leadingComments.length; j++) {
       if (
         this.state.leadingComments[j].end < this.state.commentPreviousNode.end

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

@@ -490,11 +490,7 @@ 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 +574,16 @@ 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 +598,6 @@ 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 +613,7 @@ 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;
       }
@@ -682,8 +672,8 @@ 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();
 
@@ -695,7 +685,7 @@ export default class ExpressionParser extends LValParser {
 
       node.arguments = this.parseCallExpressionArguments(
         tt.parenR,
-        maybeAsyncArrow,
+        state.maybeAsyncArrow,
         base.type === "Import",
         base.type !== "Super",
       );
@@ -705,7 +695,7 @@ export default class ExpressionParser extends LValParser {
         this.finishOptionalCallExpression(node);
       }
 
-      if (maybeAsyncArrow && this.shouldParseAsyncArrow()) {
+      if (state.maybeAsyncArrow && this.shouldParseAsyncArrow()) {
         state.stop = true;
 
         this.checkCommaAfterRestFromSpread();
@@ -722,8 +712,34 @@ 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;
@@ -1237,8 +1253,8 @@ 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;
@@ -1316,8 +1332,8 @@ 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);
@@ -1810,8 +1826,8 @@ 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;
@@ -1848,8 +1864,8 @@ 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);
     this.parseFunctionBody(node, true);
@@ -1981,7 +1997,7 @@ export default class ExpressionParser extends LValParser {
         node.params[i],
         BIND_VAR,
         allowDuplicates ? null : nameHash,
-        "function paramter list",
+        "function parameter list",
       );
     }
   }
@@ -2123,11 +2139,18 @@ 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") {
@@ -2157,10 +2180,16 @@ 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();
@@ -2189,7 +2218,7 @@ 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/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;
@@ -1743,11 +1746,11 @@ 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"`);
         }
       }
 
@@ -1762,21 +1765,10 @@ 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")
     );
   }
 
@@ -1838,10 +1830,10 @@ 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 {
@@ -2634,7 +2643,6 @@ 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 +2695,6 @@ 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"
@@ -657,7 +659,10 @@ 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 +1168,9 @@ 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 +1186,10 @@ 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 +1211,8 @@ 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 +1341,12 @@ 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 +1579,6 @@ 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 +1641,7 @@ 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 {

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).
 
@@ -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);
       }
     }
@@ -441,13 +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);
     }
 
@@ -1035,8 +1036,8 @@ export default class Tokenizer extends LocationParser {
       next = this.input.charCodeAt(this.state.pos);
     }
 
-    // disallow numeric separators in non octal decimals
-    if (this.hasPlugin("numericSeparator") && isNonOctalDecimalInt) {
+    // 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("_");

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

@@ -97,8 +97,8 @@ 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/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/es2017/async-functions/await-binding-inside-arrow-params-inside-async-arrow-params/input.js

@@ -0,0 +1 @@
+async (a = ({ await }) => {}) => {};

packages/babel-parser/test/fixtures/es2017/async-functions/await-binding-inside-arrow-params-inside-async-arrow-params/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Await cannot be used as name inside an async function (1:20)"
+}

packages/babel-parser/test/fixtures/es2017/async-functions/await-inside-async-call-inside-parameters-of-function-inside-async-function/input.js

@@ -0,0 +1,3 @@
+async function f() {
+  function g(x = async(await)) {}
+}

packages/babel-parser/test/fixtures/es2017/async-functions/await-inside-async-call-inside-parameters-of-function-inside-async-function/output.json

@@ -0,0 +1,224 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 56,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 3,
+      "column": 1
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 56,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 3,
+        "column": 1
+      }
+    },
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "FunctionDeclaration",
+        "start": 0,
+        "end": 56,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 1
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 15,
+          "end": 16,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 15
+            },
+            "end": {
+              "line": 1,
+              "column": 16
+            },
+            "identifierName": "f"
+          },
+          "name": "f"
+        },
+        "generator": false,
+        "async": true,
+        "params": [],
+        "body": {
+          "type": "BlockStatement",
+          "start": 19,
+          "end": 56,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 19
+            },
+            "end": {
+              "line": 3,
+              "column": 1
+            }
+          },
+          "body": [
+            {
+              "type": "FunctionDeclaration",
+              "start": 23,
+              "end": 54,
+              "loc": {
+                "start": {
+                  "line": 2,
+                  "column": 2
+                },
+                "end": {
+                  "line": 2,
+                  "column": 33
+                }
+              },
+              "id": {
+                "type": "Identifier",
+                "start": 32,
+                "end": 33,
+                "loc": {
+                  "start": {
+                    "line": 2,
+                    "column": 11
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 12
+                  },
+                  "identifierName": "g"
+                },
+                "name": "g"
+              },
+              "generator": false,
+              "async": false,
+              "params": [
+                {
+                  "type": "AssignmentPattern",
+                  "start": 34,
+                  "end": 50,
+                  "loc": {
+                    "start": {
+                      "line": 2,
+                      "column": 13
+                    },
+                    "end": {
+                      "line": 2,
+                      "column": 29
+                    }
+                  },
+                  "left": {
+                    "type": "Identifier",
+                    "start": 34,
+                    "end": 35,
+                    "loc": {
+                      "start": {
+                        "line": 2,
+                        "column": 13
+                      },
+                      "end": {
+                        "line": 2,
+                        "column": 14
+                      },
+                      "identifierName": "x"
+                    },
+                    "name": "x"
+                  },
+                  "right": {
+                    "type": "CallExpression",
+                    "start": 38,
+                    "end": 50,
+                    "loc": {
+                      "start": {
+                        "line": 2,
+                        "column": 17
+                      },
+                      "end": {
+                        "line": 2,
+                        "column": 29
+                      }
+                    },
+                    "callee": {
+                      "type": "Identifier",
+                      "start": 38,
+                      "end": 43,
+                      "loc": {
+                        "start": {
+                          "line": 2,
+                          "column": 17
+                        },
+                        "end": {
+                          "line": 2,
+                          "column": 22
+                        },
+                        "identifierName": "async"
+                      },
+                      "name": "async"
+                    },
+                    "arguments": [
+                      {
+                        "type": "Identifier",
+                        "start": 44,
+                        "end": 49,
+                        "loc": {
+                          "start": {
+                            "line": 2,
+                            "column": 23
+                          },
+                          "end": {
+                            "line": 2,
+                            "column": 28
+                          },
+                          "identifierName": "await"
+                        },
+                        "name": "await"
+                      }
+                    ]
+                  }
+                }
+              ],
+              "body": {
+                "type": "BlockStatement",
+                "start": 52,
+                "end": 54,
+                "loc": {
+                  "start": {
+                    "line": 2,
+                    "column": 31
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 33
+                  }
+                },
+                "body": [],
+                "directives": []
+              }
+            }
+          ],
+          "directives": []
+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/es2017/async-functions/await-object-key-inside-arrow-params-inside-async-arrow-params copy/input.js

@@ -0,0 +1 @@
+async (a = ({ await: x }) => {}) => {};

packages/babel-parser/test/fixtures/es2017/async-functions/await-object-key-inside-arrow-params-inside-async-arrow-params copy/output.json

@@ -0,0 +1,225 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 39,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 1,
+      "column": 39
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 39,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 1,
+        "column": 39
+      }
+    },
+    "sourceType": "script",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ExpressionStatement",
+        "start": 0,
+        "end": 39,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 39
+          }
+        },
+        "expression": {
+          "type": "ArrowFunctionExpression",
+          "start": 0,
+          "end": 38,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 0
+            },
+            "end": {
+              "line": 1,
+              "column": 38
+            }
+          },
+          "id": null,
+          "generator": false,
+          "async": true,
+          "params": [
+            {
+              "type": "AssignmentPattern",
+              "start": 7,
+              "end": 31,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 7
+                },
+                "end": {
+                  "line": 1,
+                  "column": 31
+                }
+              },
+              "left": {
+                "type": "Identifier",
+                "start": 7,
+                "end": 8,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 7
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 8
+                  },
+                  "identifierName": "a"
+                },
+                "name": "a"
+              },
+              "right": {
+                "type": "ArrowFunctionExpression",
+                "start": 11,
+                "end": 31,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 11
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 31
+                  }
+                },
+                "id": null,
+                "generator": false,
+                "async": false,
+                "params": [
+                  {
+                    "type": "ObjectPattern",
+                    "start": 12,
+                    "end": 24,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 12
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 24
+                      }
+                    },
+                    "properties": [
+                      {
+                        "type": "ObjectProperty",
+                        "start": 14,
+                        "end": 22,
+                        "loc": {
+                          "start": {
+                            "line": 1,
+                            "column": 14
+                          },
+                          "end": {
+                            "line": 1,
+                            "column": 22
+                          }
+                        },
+                        "method": false,
+                        "key": {
+                          "type": "Identifier",
+                          "start": 14,
+                          "end": 19,
+                          "loc": {
+                            "start": {
+                              "line": 1,
+                              "column": 14
+                            },
+                            "end": {
+                              "line": 1,
+                              "column": 19
+                            },
+                            "identifierName": "await"
+                          },
+                          "name": "await"
+                        },
+                        "computed": false,
+                        "shorthand": false,
+                        "value": {
+                          "type": "Identifier",
+                          "start": 21,
+                          "end": 22,
+                          "loc": {
+                            "start": {
+                              "line": 1,
+                              "column": 21
+                            },
+                            "end": {
+                              "line": 1,
+                              "column": 22
+                            },
+                            "identifierName": "x"
+                          },
+                          "name": "x"
+                        }
+                      }
+                    ]
+                  }
+                ],
+                "body": {
+                  "type": "BlockStatement",
+                  "start": 29,
+                  "end": 31,
+                  "loc": {
+                    "start": {
+                      "line": 1,
+                      "column": 29
+                    },
+                    "end": {
+                      "line": 1,
+                      "column": 31
+                    }
+                  },
+                  "body": [],
+                  "directives": []
+                }
+              }
+            }
+          ],
+          "body": {
+            "type": "BlockStatement",
+            "start": 36,
+            "end": 38,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 36
+              },
+              "end": {
+                "line": 1,
+                "column": 38
+              }
+            },
+            "body": [],
+            "directives": []
+          }
+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/experimental/numeric-separator/invalid-legacy-octal-literal/input.js

@@ -0,0 +1 @@
+00_0

packages/babel-parser/test/fixtures/experimental/numeric-separator/invalid-legacy-octal-literal/options.json

@@ -0,0 +1 @@
+{ "throws": "Numeric separator can not be used after leading 0 (1:2)" }

packages/babel-parser/test/fixtures/flow/interfaces-module-and-script/implements-exports/input.js

@@ -0,0 +1,3 @@
+interface Foo {}
+
+export type { Foo }

packages/babel-parser/test/fixtures/flow/interfaces-module-and-script/implements-exports/output.json

@@ -0,0 +1,160 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 37,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 3,
+      "column": 19
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 37,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 3,
+        "column": 19
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "InterfaceDeclaration",
+        "start": 0,
+        "end": 16,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 16
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 10,
+          "end": 13,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 10
+            },
+            "end": {
+              "line": 1,
+              "column": 13
+            },
+            "identifierName": "Foo"
+          },
+          "name": "Foo"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "implements": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 14,
+          "end": 16,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 14
+            },
+            "end": {
+              "line": 1,
+              "column": 16
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      },
+      {
+        "type": "ExportNamedDeclaration",
+        "start": 18,
+        "end": 37,
+        "loc": {
+          "start": {
+            "line": 3,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 19
+          }
+        },
+        "specifiers": [
+          {
+            "type": "ExportSpecifier",
+            "start": 32,
+            "end": 35,
+            "loc": {
+              "start": {
+                "line": 3,
+                "column": 14
+              },
+              "end": {
+                "line": 3,
+                "column": 17
+              }
+            },
+            "local": {
+              "type": "Identifier",
+              "start": 32,
+              "end": 35,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 14
+                },
+                "end": {
+                  "line": 3,
+                  "column": 17
+                },
+                "identifierName": "Foo"
+              },
+              "name": "Foo"
+            },
+            "exported": {
+              "type": "Identifier",
+              "start": 32,
+              "end": 35,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 14
+                },
+                "end": {
+                  "line": 3,
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+  }
+}

packages/babel-parser/test/fixtures/flow/multiple-declarations/class/input.js

@@ -0,0 +1,2 @@
+declare class C1 {}
+class C1 {}

packages/babel-parser/test/fixtures/flow/multiple-declarations/class/options.json

@@ -0,0 +1,8 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "jsx",
+    "flow"
+  ],
+  "throws": "Identifier 'C1' has already been declared (2:6)"
+}

packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-class/input.js

@@ -0,0 +1,6 @@
+declare class C1{}
+declare class C1{}
+
+declare module M1 {
+  declare class C1 {}
+}

packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-class/output.json

@@ -0,0 +1,253 @@
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packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-function/input.js

@@ -0,0 +1,3 @@
+declare function F1(): void
+declare function F1(): void
+function F1() {}

packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-function/output.json

@@ -0,0 +1,249 @@
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packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-var/input.js

@@ -0,0 +1,3 @@
+declare var V1;
+declare var V1;
+var V1;

packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-var/output.json

@@ -0,0 +1,150 @@
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packages/babel-parser/test/fixtures/flow/multiple-declarations/interface/input.js

@@ -0,0 +1,2 @@
+interface I {};
+interface I {};

packages/babel-parser/test/fixtures/flow/multiple-declarations/interface/options.json

@@ -0,0 +1,8 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "jsx",
+    "flow"
+  ],
+  "throws": "Identifier 'I' has already been declared (2:10)"
+}

packages/babel-parser/test/fixtures/flow/multiple-declarations/type/input.js

@@ -0,0 +1,2 @@
+type T1 = string;
+type T1 = number;

packages/babel-parser/test/fixtures/flow/multiple-declarations/type/options.json

@@ -0,0 +1,8 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "jsx",
+    "flow"
+  ],
+  "throws": "Identifier 'T1' has already been declared (2:5)"
+}

packages/babel-parser/test/fixtures/flow/regression/issue-10044/input.js

@@ -0,0 +1,8 @@
+declare class C1 {}
+declare interface I1 {}
+declare type T1 = number;
+
+interface I2 {}
+type T2 = number;
+
+export type { C1, I1, I2, T1, T2 }

packages/babel-parser/test/fixtures/flow/regression/issue-10044/output.json

@@ -0,0 +1,564 @@
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packages/babel-parser/test/fixtures/flow/regression/issue-10314/input.js

@@ -0,0 +1,3 @@
+// @flow
+
+true ? async.waterfall() : null;

packages/babel-parser/test/fixtures/flow/regression/issue-10314/output.json

@@ -0,0 +1,198 @@
+{
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+  "end": 42,
+  "loc": {
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+      "column": 0
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+    "end": {
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+      "column": 32
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+  },
+  "program": {
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+        "column": 32
+      }
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+            "column": 0
+          },
+          "end": {
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+            "column": 32
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+        },
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+            "end": {
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+              "column": 31
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+          },
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+            "end": 14,
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+              },
+              "end": {
+                "line": 3,
+                "column": 4
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+            },
+            "value": true
+          },
+          "consequent": {
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+            "end": 34,
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+                "column": 24
+              }
+            },
+            "callee": {
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+                },
+                "end": {
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+                  "column": 22
+                }
+              },
+              "object": {
+                "type": "Identifier",
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+                "end": 22,
+                "loc": {
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+                    "line": 3,
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+                  },
+                  "end": {
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+                  "identifierName": "async"
+                },
+                "name": "async"
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+            "end": 41,
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+              },
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+              }
+            }
+          }
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+              },
+              "end": {
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+                "column": 8
+              }
+            }
+          }
+        ]
+      }
+    ],
+    "directives": []
+  },
+  "comments": [
+    {
+      "type": "CommentLine",
+      "value": " @flow",
+      "start": 0,
+      "end": 8,
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 0
+        },
+        "end": {
+          "line": 1,
+          "column": 8
+        }
+      }
+    }
+  ]
+}

packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-declare-var/options.json

@@ -1,3 +0,0 @@
-{
-  "throws": "Identifier 'A' has already been declared (2:12)"
-}

packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-func/options.json

@@ -1,3 +0,0 @@
-{
-  "throws": "Identifier 'A' has already been declared (2:9)"
-}

packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-var-let/options.json

@@ -1,3 +0,0 @@
-{
-  "throws": "Identifier 'A' has already been declared (2:4)"
-}

packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-declare-class/options.json

@@ -1,3 +0,0 @@
-{
-  "throws": "Identifier 'A' has already been declared (2:14)"
-}

packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-class-declare-class/output.json

@@ -0,0 +1,147 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 37,
+  "loc": {
+    "start": {
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+      "column": 0
+    },
+    "end": {
+      "line": 2,
+      "column": 18
+    }
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+  "program": {
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+    "end": 37,
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+        "line": 2,
+        "column": 18
+      }
+    },
+    "sourceType": "module",
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+        "end": 18,
+        "loc": {
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+            "column": 0
+          },
+          "end": {
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+            "column": 18
+          }
+        },
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+            },
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+            },
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+        "mixins": [],
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+          "end": 18,
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+            },
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+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      },
+      {
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+        "end": 37,
+        "loc": {
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+          }
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+          "end": 34,
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+            },
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+              "line": 2,
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+            },
+            "identifierName": "A"
+          },
+          "name": "A"
+        },
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+        "implements": [],
+        "mixins": [],
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+          "end": 37,
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+            },
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+              "column": 18
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-declare-var/output.json

@@ -0,0 +1,178 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 50,
+  "loc": {
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+      }
+    },
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+            },
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+            "end": 26,
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