v7.0.0-beta.36

* preset-env: Move all defaults to the separate module.

* preset-env: Add test cases for defaults.

.babelignore

@@ -2,3 +2,4 @@
 packages/*/test/fixtures
 packages/*/lib
 packages/babel-standalone/babel.js
+packages/babel-preset-env-standalone/babel-preset-env.js

.babelrc.js

@@ -32,7 +32,6 @@ function istanbulHacks() {
 
 let envOpts = {
   loose: true,
-  exclude: ["transform-typeof-symbol"],
 };
 
 const config = {
@@ -43,9 +42,9 @@ const config = {
   ],
   plugins: [
     ["@babel/proposal-class-properties", { loose: true }],
-    "@babel/proposal-export-namespace",
+    "@babel/proposal-export-namespace-from",
     "@babel/proposal-numeric-separator",
-    ["@babel/proposal-object-rest-spread", { useBuiltIns: true}],
+    ["@babel/proposal-object-rest-spread", { useBuiltIns: true }],
   ]
 };
 

.editorconfig

@@ -9,3 +9,6 @@ end_of_line = lf
 [*.{js,json}]
 indent_style = space
 indent_size = 2
+
+[*.{md,markdown}]
+trim_trailing_whitespace = false

.eslintignore

@@ -12,12 +12,10 @@ codemods/*/lib
 codemods/*/dist
 codemods/*/test/fixtures
 codemods/*/test/tmp
-experimental/*/lib
-experimental/*/node_modules
-experimental/*/test/fixtures
-experimental/*/test/tmp
-experimental/babel-preset-env/data
-experimental/babel-preset-env/test/debug-fixtures
+packages/babel-preset-env/data
+packages/babel-preset-env/test/debug-fixtures
+packages/babel-preset-env-standalone/babel-preset-env.js
+packages/babel-preset-env-standalone/babel-preset-env.min.js
 packages/babel-standalone/babel.js
 packages/babel-standalone/babel.min.js
 packages/babylon/build

.eslintrc

@@ -15,7 +15,6 @@
     {
       "files": [
         "packages/*/src/**/*.js",
-        "experimental/*/src/**/*.js",
         "codemods/*/src/**/*.js"
       ],
       "rules": {
@@ -23,7 +22,11 @@
       }
     },
     {
-      "files": [ "packages/*/test/**/*.js", "test/**/*.js" ],
+      "files": [
+        "packages/*/test/**/*.js",
+        "codemods/*/test/**/*.js",
+        "test/**/*.js"
+      ],
       "env": {
         "mocha": true
       }

.flowconfig

@@ -4,14 +4,11 @@
 .*/packages/.*/test
 .*/codemods/.*/lib
 .*/codemods/.*/test
-.*/experimental/.*/lib
-.*/experimental/.*/test
 .*/node_modules/conventional-changelog-core/
 
 [include]
 packages/*/src
 codemods/*/src
-experimental/*/src
 
 [libs]
 lib/file.js
@@ -20,6 +17,7 @@ lib/types.js
 lib/third-party-libs.js.flow
 
 [options]
+include_warnings=true
 suppress_comment= \\(.\\|\n\\)*\\$FlowFixMe
 suppress_comment= \\(.\\|\n\\)*\\$FlowIssue
 suppress_comment= \\(.\\|\n\\)*\\$FlowIgnore

.gitignore

@@ -34,6 +34,9 @@ package-lock.json
 /babel.sublime-workspace
 packages/babel-standalone/babel.js
 packages/babel-standalone/babel.min.js
+packages/babel-preset-env-standalone/babel-preset-env.js
+packages/babel-preset-env-standalone/babel-preset-env.min.js
 /codemods/*/lib
 /codemods/*/node_modules
 /packages/babylon/build
+.idea/

.prettierrc

@@ -2,8 +2,6 @@
   "trailingComma": "es5",
   "overrides": [{
     "files": [
-      "**/experimental/*/src/**/*.js",
-      "**/experimental/*/test/**/*.js",
       "**/codemods/*/src/**/*.js",
       "**/codemods/*/test/**/*.js",
       "**/packages/*/src/**/*.js",

CONTRIBUTING.md

@@ -24,7 +24,7 @@ contributing, please read the
 ## Not sure where to start?
 
 - If you aren't just making a documentation change, you'll probably want to learn a bit about a few topics.
- - [ASTs](https://en.wikipedia.org/wiki/Abstract_syntax_tree) (Abstract Syntax Tree): The Babel AST [spec](https://github.com/babel/babel/tree/master/packages/babylon/blob/master/ast/spec.md) is a bit different from [ESTree](https://github.com/estree/estree). The differences are listed [here](https://github.com/babel/babel/tree/master/packages/babylon#output).
+ - [ASTs](https://en.wikipedia.org/wiki/Abstract_syntax_tree) (Abstract Syntax Tree): The Babel AST [spec](https://github.com/babel/babel/blob/master/packages/babylon/ast/spec.md) is a bit different from [ESTree](https://github.com/estree/estree). The differences are listed [here](https://github.com/babel/babel/tree/master/packages/babylon#output).
  - Check out [`/doc`](https://github.com/babel/babel/tree/master/doc) for information about Babel's internals
  - Check out [the Babel Plugin Handbook](https://github.com/thejameskyle/babel-handbook/blob/master/translations/en/plugin-handbook.md#babel-plugin-handbook) - core plugins are written the same way as any other plugin!
  - Check out [AST Explorer](http://astexplorer.net/#/scUfOmVOG5) to learn more about ASTs or make your own plugin in the browser
@@ -115,7 +115,7 @@ $ TEST_ONLY=babel-cli make test
 `TEST_ONLY` will also match substrings of the package name:
 
 ```sh
-# Run tests for the babel-plugin-transform-classes package.
+# Run tests for the @babel/plugin-transform-classes package.
 $ TEST_ONLY=es2015-class make test
 ```
 
@@ -161,16 +161,16 @@ In case you're locally getting errors which are not on the CI, it may be due to
 
 Most packages in [`/packages`](https://github.com/babel/babel/tree/master/packages) have a `test` folder, however some tests might be in other packages or in [`/packages/babel-core`](https://github.com/babel/babel/tree/master/packages/babel-core/test/fixtures).
 
-#### `babel-plugin-x`
+#### `@babel/plugin-x`
 
 All the Babel plugins (and other packages) that have a `/test/fixtures` are written in a similar way.
 
-For example, in [`babel-plugin-transform-exponentiation-operator/test`](https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-exponentiation-operator/test):
+For example, in [`@babel/plugin-transform-exponentiation-operator/test`](https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-exponentiation-operator/test):
 
 - There is an `index.js` file. It imports our [test helper](https://github.com/babel/babel/tree/master/packages/babel-helper-plugin-test-runner). (You don't have to worry about this).
 - There can be multiple folders under [`/fixtures`](https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures)
    - There is an [`options.json`](https://github.com/babel/babel/blob/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/options.json) file whose function is similar to a `.babelrc` file, allowing you to pass in the plugins and settings you need for your tests.
-   - For this test, we only need the relevant plugin, so it's just `{ "plugins": ["@babel/transform-exponentiation-operator"] }`.
+   - For this test, we only need the relevant plugin, so it's just `{ "plugins": ["@babel/plugin-transform-exponentiation-operator"] }`.
    - If necessary, you can have an `options.json` with different options in each subfolder.
 
 - In each subfolder, you can organize your directory structure by categories of tests. (Example: these folders can be named after the feature you are testing or can reference the issue number they fix)
@@ -205,8 +205,8 @@ If you need to check for an error that is thrown you can add to the `options.jso
 ```js
 // options.json example
 {
-  "plugins": [["@babel/proposal-object-rest-spread", { "useBuiltIns": "invalidOption" }]],
-  "throws": "@babel/proposal-object-rest-spread currently only accepts a boolean option for useBuiltIns (defaults to false)"
+  "plugins": [["@babel/plugin-proposal-object-rest-spread", { "useBuiltIns": "invalidOption" }]],
+  "throws": "@babel/plugin-proposal-object-rest-spread currently only accepts a boolean option for useBuiltIns (defaults to false)"
 }
 ```
 
@@ -231,9 +231,21 @@ descriptive name, and add the following:
 
 * Add an `expected.json` file with the expected parser output. For added convenience, if there is no `expected.json` present, the test runner will generate one for you.
 
+After writing tests for babylon, just build it by running:
+
+```sh
+$ make build-babylon
+```
+
+Then, to run the tests, use:
+
+```sh
+$ TEST_ONLY=babylon make test-only
+```
+
 #### Bootstrapping expected output
 
-For both `babel-plugin-x` and `babylon`, you can easily generate an `expected.js`/`expected.json` automatically by just providing `actual.js` and running the tests as you usually would.
+For both `@babel/plugin-x` and `babylon`, you can easily generate an `expected.js`/`expected.json` automatically by just providing `actual.js` and running the tests as you usually would.
 
 ```
 // Example
@@ -267,7 +279,7 @@ To include the changes, we have to make sure to build Babel:
 $ make build
 ```
 
-Next, we need to execute `Generator.generate()`, which can be achieved by running a test case in the `babel-generator` package.
+Next, we need to execute `Generator.generate()`, which can be achieved by running a test case in the `@babel/generator` package.
 For example, we can run the test case that tests the generation of class declarations:
 
 ```bash
@@ -275,7 +287,6 @@ $ TEST_DEBUG=true TEST_GREP=ClassDeclaration make test-only
 
 ./scripts/test.sh
 Debugger listening on port 9229.
-Warning: This is an experimental feature and could change at any time.
 To start debugging, open the following URL in Chrome:
     chrome-devtools://devtools/remote/serve_file/@60cd6e859b9f557d2312f5bf532f6aec5f284980/inspector.html?experiments=true&v8only=true&ws=127.0.0.1:9229/3cdaebd2-be88-4e7b-a94b-432950ab72d0
 ```
@@ -298,8 +309,8 @@ Note that the code shown in Chrome DevTools is compiled code and therefore diffe
 - Start working about the Babel transform itself!
 
 ## Internals
-- AST spec ([babylon/ast/spec.md](https://github.com/babel/babel/tree/master/packages/babylon/blob/master/ast/spec.md))
-- Versioning ([doc/design/versioning.md](https://github.com/babel/babel/blob/master/doc/design/versioning.md)
+- AST spec ([babylon/ast/spec.md](https://github.com/babel/babel/blob/master/packages/babylon/ast/spec.md))
+- Versioning ([doc/design/versioning.md](https://github.com/babel/babel/blob/master/doc/design/versioning.md))
 - Monorepo ([doc/design/monorepo.md](https://github.com/babel/babel/blob/master/doc/design/monorepo.md))
 - Compiler environment support ([doc/design/compiler-environment-support.md](https://github.com/babel/babel/blob/master/doc/design/compiler-environment-support.md))
 - Compiler assumptions ([doc/design/compiler-assumptions.md](https://github.com/babel/babel/blob/master/doc/design/compiler-assumptions.md))

Gulpfile.js

@@ -3,9 +3,6 @@
 const plumber = require("gulp-plumber");
 const through = require("through2");
 const chalk = require("chalk");
-const pump = require("pump");
-const uglify = require("gulp-uglify");
-const rename = require("gulp-rename");
 const newer = require("gulp-newer");
 const babel = require("gulp-babel");
 const watch = require("gulp-watch");
@@ -13,13 +10,12 @@ const gutil = require("gulp-util");
 const filter = require("gulp-filter");
 const gulp = require("gulp");
 const path = require("path");
-const merge = require("merge-stream");
-const RootMostResolvePlugin = require("webpack-dependency-suite")
-  .RootMostResolvePlugin;
 const webpack = require("webpack");
-const webpackStream = require("webpack-stream");
+const merge = require("merge-stream");
+const registerStandalonePackageTask = require("./scripts/gulp-tasks")
+  .registerStandalonePackageTask;
 
-const sources = ["codemods", "packages", "experimental"];
+const sources = ["codemods", "packages"];
 
 function swapSrcWithLib(srcPath) {
   const parts = srcPath.split(path.sep);
@@ -81,114 +77,40 @@ gulp.task("watch", ["build"], function() {
   });
 });
 
-gulp.task("build-babel-standalone", cb => {
-  pump(
-    [
-      gulp.src(__dirname + "/packages/babel-standalone/src/index.js"),
-      webpackBuild(),
-      gulp.dest(__dirname + "/packages/babel-standalone"),
-      uglify(),
-      rename({ extname: ".min.js" }),
-      gulp.dest(__dirname + "/packages/babel-standalone"),
-    ],
-    cb
-  );
-});
+registerStandalonePackageTask(
+  gulp,
+  "babel",
+  "Babel",
+  path.join(__dirname, "packages"),
+  require("./packages/babel-core/package.json").version
+);
 
-function webpackBuild() {
-  let version = require("./packages/babel-core/package.json").version;
+const presetEnvWebpackPlugins = [
+  new webpack.NormalModuleReplacementPlugin(
+    /\.\/available-plugins/,
+    require.resolve(
+      path.join(
+        __dirname,
+        "./packages/babel-preset-env-standalone/src/available-plugins"
+      )
+    )
+  ),
+  new webpack.NormalModuleReplacementPlugin(
+    /caniuse-lite\/data\/regions\/.+/,
+    require.resolve(
+      path.join(
+        __dirname,
+        "./packages/babel-preset-env-standalone/src/caniuse-lite-regions"
+      )
+    )
+  ),
+];
 
-  // If this build is part of a pull request, include the pull request number in
-  // the version number.
-  if (process.env.CIRCLE_PR_NUMBER) {
-    version += "+pr." + process.env.CIRCLE_PR_NUMBER;
-  }
-
-  const config = {
-    module: {
-      rules: [
-        {
-          test: /\.js$/,
-          include: /node_modules/,
-          loader: "babel-loader",
-          options: {
-            // Some of the node_modules may have their own "babel" section in
-            // their project.json (or a ".babelrc" file). We need to ignore
-            // those as we're using our own Babel options.
-            babelrc: false,
-            presets: [
-              [
-                "@babel/env",
-                {
-                  loose: true,
-                  exclude: ["transform-typeof-symbol"],
-                },
-              ],
-            ],
-          },
-        },
-        {
-          test: /\.js$/,
-          exclude: /node_modules/,
-          loader: "babel-loader",
-          options: {
-            // Some of the node_modules may have their own "babel" section in
-            // their project.json (or a ".babelrc" file). We need to ignore
-            // those as we're using our own Babel options.
-            babelrc: false,
-            presets: [
-              [
-                "@babel/env",
-                {
-                  loose: true,
-                  exclude: ["transform-typeof-symbol"],
-                },
-              ],
-              ["@babel/stage-0", { loose: true }],
-            ],
-          },
-        },
-      ],
-      // babylon is already bundled and does not require parsing
-      noParse: [/babylon\/lib/],
-    },
-    node: {
-      // Mock Node.js modules that Babel require()s but that we don't
-      // particularly care about.
-      fs: "empty",
-      module: "empty",
-      net: "empty",
-    },
-    output: {
-      filename: "babel.js",
-      library: "Babel",
-      libraryTarget: "umd",
-    },
-    plugins: [
-      new webpack.DefinePlugin({
-        "process.env.NODE_ENV": '"production"',
-        BABEL_VERSION: JSON.stringify(version),
-        VERSION: JSON.stringify(version),
-      }),
-      /*new webpack.NormalModuleReplacementPlugin(
-        /..\/..\/package/,
-        "../../../../src/babel-package-shim"
-      ),*/
-      new webpack.optimize.ModuleConcatenationPlugin(),
-    ],
-    resolve: {
-      plugins: [
-        // Dedupe packages that are used across multiple plugins.
-        // This replaces DedupePlugin from Webpack 1.x
-        new RootMostResolvePlugin(__dirname, true),
-      ],
-    },
-  };
-
-  return webpackStream(config, webpack);
-  // To write JSON for debugging:
-  /*return webpackStream(config, webpack, (err, stats) => {
-    require('gulp-util').log(stats.toString({colors: true}));
-    require('fs').writeFileSync('webpack-debug.json', JSON.stringify(stats.toJson()));
-  });*/
-}
+registerStandalonePackageTask(
+  gulp,
+  "babel-preset-env",
+  "babelPresetEnv",
+  path.join(__dirname, "packages"),
+  require("./packages/babel-preset-env/package.json").version,
+  presetEnvWebpackPlugins
+);

Makefile

@@ -1,5 +1,5 @@
 MAKEFLAGS = -j1
-FLOW_COMMIT = 4cc2b9f7fadf2e9e445ee9b7b980c65d69d3fbc0
+FLOW_COMMIT = 622bbc4f07acb77eb1109830c70815f827401d90
 TEST262_COMMIT = 1282e842febf418ca27df13fa4b32f7e5021b470
 
 export NODE_ENV = test
@@ -7,7 +7,7 @@ export NODE_ENV = test
 # Fix color output until TravisCI fixes https://github.com/travis-ci/travis-ci/issues/7967
 export FORCE_COLOR = true
 
-SOURCES = packages codemods experimental
+SOURCES = packages codemods
 
 .PHONY: build build-dist watch lint fix clean test-clean test-only test test-ci publish bootstrap
 
@@ -16,8 +16,12 @@ build: clean
   # Build babylon before building all other projects
 	make build-babylon
 	./node_modules/.bin/gulp build
+	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
 ifneq ("$(BABEL_ENV)", "cov")
 	make build-standalone
+	make build-preset-env-standalone
 endif
 
 build-babylon:
@@ -27,6 +31,9 @@ build-babylon:
 build-standalone:
 	./node_modules/.bin/gulp build-babel-standalone
 
+build-preset-env-standalone:
+	./node_modules/.bin/gulp build-babel-preset-env-standalone
+
 build-dist: build
 	cd packages/babel-polyfill; \
 	scripts/build-dist.sh
@@ -38,6 +45,10 @@ watch: clean
 	make clean-lib
 	BABEL_ENV=development ./node_modules/.bin/gulp watch
 
+watch-babylon:
+	cd packages/babylon; \
+	./node_modules/.bin/rollup -c -w
+
 flow:
 	./node_modules/.bin/flow check --strip-root
 
@@ -50,8 +61,6 @@ fix:
 clean: test-clean
 	rm -rf packages/babel-polyfill/browser*
 	rm -rf packages/babel-polyfill/dist
-	# rm -rf packages/babel-runtime/helpers
-	# rm -rf packages/babel-runtime/core-js
 	rm -rf coverage
 	rm -rf packages/*/npm-debug*
 
@@ -110,6 +119,8 @@ test-test262-update-whitelist:
 publish:
 	git pull --rebase
 	make clean-lib
+	rm -rf packages/babel-runtime/helpers
+	rm -rf packages/babel-runtime/core-js
 	BABEL_ENV=production make build-dist
 	make test
 	# not using lerna independent mode atm, so only update packages that have changed since we use ^

README.md

@@ -24,9 +24,9 @@
   <a href="https://medium.com/friendship-dot-js/i-peeked-into-my-node-modules-directory-and-you-wont-believe-what-happened-next-b89f63d21558"><img alt="Business Strategy Status" src="https://img.shields.io/badge/business%20model-flavortown-green.svg"></a>
 </p>
 
-Babel is community-driven and thus mostly maintained by a group of [volunteers](https://babeljs.io/team). It has a lot of [companies and projects](http://babeljs.io/users) using it but almost no sponsors/people funded to work on it. If you'd like to help maintain the future of the project, please consider:
+Babel is community-driven and thus mostly maintained by a group of [volunteers](https://babeljs.io/team). It has a lot of [companies and projects](https://babeljs.io/users) using it but almost no sponsors/people funded to work on it. If you'd like to help maintain the future of the project, please consider:
 
-- Giving developer time on the project. (Message us on [Twitter](https://twitter.com/babeljs) or [Slack](slack.babeljs.io))
+- Giving developer time on the project. (Message us on [Twitter](https://twitter.com/babeljs) or [Slack](https://slack.babeljs.io/))
 - [Giving funds by becoming a backer/sponsor on OpenCollective](https://opencollective.com/babel)
 
 ## Intro
@@ -63,19 +63,23 @@ Mostly a handful of volunteers! Please check out our [team page](https://babeljs
 
 ### Looking for support?
 
-For questions and support please visit join our [Slack Community](https://slack.babeljs.io/), ask a question on [Stack Overflow](http://stackoverflow.com/questions/tagged/babeljs), or ping us on [Twitter](https://twitter.com/babeljs/).
+For questions and support please visit join our [Slack Community](https://slack.babeljs.io/), ask a question on [Stack Overflow](https://stackoverflow.com/questions/tagged/babeljs), or ping us on [Twitter](https://twitter.com/babeljs).
+
+### Is there a Babel song?
+
+I'm so glad you asked: [Hallelujah —— In Praise of Babel](SONG.md) by [@angus-c](https://github.com/angus-c). Tweet us your recordings!
 
 ### Where are the docs?
 
-Check out our website: [babeljs.io](http://babeljs.io/), and report issues/features at [babel/website](https://github.com/babel/website/issues).
+Check out our website: [babeljs.io](https://babeljs.io/), and report issues/features at [babel/website](https://github.com/babel/website/issues).
 
 ### Want to report a bug or request a feature?
 
-Please read through our [CONTRIBUTING.md](https://github.com/babel/babel/blob/master/CONTRIBUTING.md) and fill out the issue template at [babel/issues](https://github.com/babel/babel/issues)!
+Please read through our [CONTRIBUTING.md](CONTRIBUTING.md) and fill out the issue template at [babel/issues](https://github.com/babel/babel/issues)!
 
 ### Want to contribute to Babel?
 
-Check out our [CONTRIBUTING.md](https://github.com/babel/babel/blob/master/CONTRIBUTING.md) to get started with setting up the repo.
+Check out our [CONTRIBUTING.md](CONTRIBUTING.md) to get started with setting up the repo.
 
 - If you have already joined Slack, join our [#development](https://babeljs.slack.com/messages/development) channel and say hi!
 - Check out the issues with the [good first issue](https://github.com/babel/babel/labels/good%20first%20issue) and [help wanted](https://github.com/babel/babel/labels/help%20wanted) label. We suggest also looking at the closed ones to get a sense of the kinds of issues you can tackle.
@@ -84,7 +88,7 @@ Check out our [CONTRIBUTING.md](https://github.com/babel/babel/blob/master/CONTR
 
 ### How is the repo structured?
 
-The Babel repo is managed as a [monorepo](https://github.com/babel/babel/blob/master/doc/design/monorepo.md) that is composed of many [npm packages](/packages#readme).
+The Babel repo is managed as a [monorepo](doc/design/monorepo.md) that is composed of many [npm packages](packages/README.md).
 
 ## Backers
 
@@ -95,30 +99,30 @@ Support us with a monthly donation and help us continue our activities. [[Become
 <a href="https://opencollective.com/babel/backer/2/website" target="_blank"><img src="https://opencollective.com/babel/backer/2/avatar.svg"></a>
 <a href="https://opencollective.com/babel/backer/3/website" target="_blank"><img src="https://opencollective.com/babel/backer/3/avatar.svg"></a>
 <a href="https://opencollective.com/babel/backer/4/website" target="_blank"><img src="https://opencollective.com/babel/backer/4/avatar.svg"></a>
-<a href="https://opencollective.com/babel/backer/5/website" target="_blank"><img src="https://opencollective.com/babel/backer/5/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/6/website" target="_blank"><img src="https://opencollective.com/babel/backer/6/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/7/website" target="_blank"><img src="https://opencollective.com/babel/backer/7/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/8/website" target="_blank"><img src="https://opencollective.com/babel/backer/8/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/9/website" target="_blank"><img src="https://opencollective.com/babel/backer/9/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/10/website" target="_blank"><img src="https://opencollective.com/babel/backer/10/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/11/website" target="_blank"><img src="https://opencollective.com/babel/backer/11/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/12/website" target="_blank"><img src="https://opencollective.com/babel/backer/12/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/13/website" target="_blank"><img src="https://opencollective.com/babel/backer/13/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/14/website" target="_blank"><img src="https://opencollective.com/babel/backer/14/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/15/website" target="_blank"><img src="https://opencollective.com/babel/backer/15/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/16/website" target="_blank"><img src="https://opencollective.com/babel/backer/16/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/17/website" target="_blank"><img src="https://opencollective.com/babel/backer/17/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/18/website" target="_blank"><img src="https://opencollective.com/babel/backer/18/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/19/website" target="_blank"><img src="https://opencollective.com/babel/backer/19/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/20/website" target="_blank"><img src="https://opencollective.com/babel/backer/20/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/21/website" target="_blank"><img src="https://opencollective.com/babel/backer/21/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/22/website" target="_blank"><img src="https://opencollective.com/babel/backer/22/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/23/website" target="_blank"><img src="https://opencollective.com/babel/backer/23/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/24/website" target="_blank"><img src="https://opencollective.com/babel/backer/24/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/25/website" target="_blank"><img src="https://opencollective.com/babel/backer/25/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/26/website" target="_blank"><img src="https://opencollective.com/babel/backer/26/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/27/website" target="_blank"><img src="https://opencollective.com/babel/backer/27/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/backer/28/website" target="_blank"><img src="https://opencollective.com/babel/backer/28/avatar.svg"></a>		
+<a href="https://opencollective.com/babel/backer/5/website" target="_blank"><img src="https://opencollective.com/babel/backer/5/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/6/website" target="_blank"><img src="https://opencollective.com/babel/backer/6/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/7/website" target="_blank"><img src="https://opencollective.com/babel/backer/7/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/8/website" target="_blank"><img src="https://opencollective.com/babel/backer/8/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/9/website" target="_blank"><img src="https://opencollective.com/babel/backer/9/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/10/website" target="_blank"><img src="https://opencollective.com/babel/backer/10/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/11/website" target="_blank"><img src="https://opencollective.com/babel/backer/11/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/12/website" target="_blank"><img src="https://opencollective.com/babel/backer/12/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/13/website" target="_blank"><img src="https://opencollective.com/babel/backer/13/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/14/website" target="_blank"><img src="https://opencollective.com/babel/backer/14/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/15/website" target="_blank"><img src="https://opencollective.com/babel/backer/15/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/16/website" target="_blank"><img src="https://opencollective.com/babel/backer/16/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/17/website" target="_blank"><img src="https://opencollective.com/babel/backer/17/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/18/website" target="_blank"><img src="https://opencollective.com/babel/backer/18/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/19/website" target="_blank"><img src="https://opencollective.com/babel/backer/19/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/20/website" target="_blank"><img src="https://opencollective.com/babel/backer/20/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/21/website" target="_blank"><img src="https://opencollective.com/babel/backer/21/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/22/website" target="_blank"><img src="https://opencollective.com/babel/backer/22/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/23/website" target="_blank"><img src="https://opencollective.com/babel/backer/23/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/24/website" target="_blank"><img src="https://opencollective.com/babel/backer/24/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/25/website" target="_blank"><img src="https://opencollective.com/babel/backer/25/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/26/website" target="_blank"><img src="https://opencollective.com/babel/backer/26/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/27/website" target="_blank"><img src="https://opencollective.com/babel/backer/27/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/backer/28/website" target="_blank"><img src="https://opencollective.com/babel/backer/28/avatar.svg"></a>
   <a href="https://opencollective.com/babel/backer/29/website" target="_blank"><img src="https://opencollective.com/babel/backer/29/avatar.svg"></a>
 
 ## Sponsors
@@ -130,32 +134,32 @@ Become a sponsor and get your logo on our README on Github with a link to your s
 <a href="https://opencollective.com/babel/sponsor/2/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/2/avatar.svg"></a>
 <a href="https://opencollective.com/babel/sponsor/3/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/3/avatar.svg"></a>
 <a href="https://opencollective.com/babel/sponsor/4/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/4/avatar.svg"></a>
- <a href="https://opencollective.com/babel/sponsor/5/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/5/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/6/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/6/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/7/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/7/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/8/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/8/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/9/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/9/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/10/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/10/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/11/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/11/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/12/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/12/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/13/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/13/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/14/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/14/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/15/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/15/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/16/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/16/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/17/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/17/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/18/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/18/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/19/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/19/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/20/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/20/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/21/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/21/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/22/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/22/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/23/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/23/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/24/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/24/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/25/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/25/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/26/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/26/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/27/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/27/avatar.svg"></a>		
-  <a href="https://opencollective.com/babel/sponsor/28/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/28/avatar.svg"></a>		
+ <a href="https://opencollective.com/babel/sponsor/5/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/5/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/6/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/6/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/7/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/7/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/8/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/8/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/9/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/9/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/10/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/10/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/11/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/11/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/12/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/12/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/13/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/13/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/14/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/14/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/15/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/15/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/16/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/16/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/17/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/17/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/18/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/18/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/19/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/19/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/20/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/20/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/21/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/21/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/22/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/22/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/23/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/23/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/24/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/24/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/25/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/25/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/26/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/26/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/27/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/27/avatar.svg"></a>
+  <a href="https://opencollective.com/babel/sponsor/28/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/28/avatar.svg"></a>
   <a href="https://opencollective.com/babel/sponsor/29/website" target="_blank"><img src="https://opencollective.com/babel/sponsor/29/avatar.svg"></a>
 
 ## License
 
-[MIT](https://github.com/babel/babel/blob/master/LICENSE)
+[MIT](LICENSE)

SONG.md

@@ -0,0 +1,67 @@
+## Hallelujah—In Praise of Babel
+
+I heard there was a clever trick  
+That rewrote all your JavaScript  
+But you don’t really care for magic, do you  
+Well it goes like this: the source, the dist  
+The ES five, the ES six  
+The sacred script transforming Hallelujah  
+
+Hallelujah, Hallelujah  
+Hallelujah, Hallelujah
+
+So I added all the shiny things  
+Classes, spreads and template strings  
+Through syntax sugared code I tried to woo you  
+Generators, const and let  
+I used them all without regret  
+And it’s a terse and a destructured Hallelujah  
+
+Hallelujah etc.
+
+Well my faith was strong but I needed proof  
+The standard was my source of truth  
+But TC39 meant nothing to you  
+So even though you weren’t impressed  
+I checked the build against the spec  
+And it’s a more-or-less compliant Hallelujah  
+
+Hallelujah etc.
+
+Now you say the build step’s too complex  
+And you claim no need for ES Next  
+Well I used to think that way before I knew you  
+But your code grows older with each line  
+It’s a joyless dirge on a withered vine  
+It’s a threnody for a bygone Hallelujah  
+
+Hallelujah etc.
+
+Yes I learned about the danger signs  
+How they’d polyfilled a thousand lines  
+The cost of using Maps and Symbols threw you  
+Still I disregarded common sense  
+Now my source is small but the build’s immense  
+And it’s a slow and unresponsive Hallelujah  
+
+Hallelujah etc.
+
+There was a time when they let me know  
+What’s really going on below  
+But now there’s only source maps there to school you  
+And debugging’s not a progress march  
+It’s a frenzied fumble in the dark  
+It’s a labyrinthine search for Hallelujah  
+
+Hallelujah etc.
+
+Well, maybe there’s a god up there  
+But all I ever got from prayers  
+Was broken builds and errors that would spook you  
+And that anguished cry you hear at night  
+Is the plugin I forgot to write  
+It’s a cold and it’s a broken Hallelujah  
+
+Hallelujah etc.
+
+[Angus Croll](https://github.com/angus-c)  

circle.yml

@@ -2,6 +2,8 @@ general:
   artifacts:
     - "packages/babel-standalone/babel.js"
     - "packages/babel-standalone/babel.min.js"
+    - "packages/babel-preset-env-standalone/babel-preset-env.js"
+    - "packages/babel-preset-env-standalone/babel-preset-env.min.js"
 
 machine:
   node:
@@ -25,3 +27,4 @@ test:
     # data for a JS file that's several megabytes large is bound to fail. Here,
     # we just run the babel-standalone test separately.
     - ./node_modules/mocha/bin/_mocha packages/babel-standalone/test/ --opts test/mocha.opts
+    - ./node_modules/mocha/bin/_mocha packages/babel-preset-env-standalone/test/ --opts test/mocha.opts

codemods/.eslintrc

@@ -1,6 +0,0 @@
-{
-  "rules": {
-    "prettier/prettier": ["error", { "trailingComma": "all" }],
-    "no-undefined-identifier": 2
-  }
-}

codemods/babel-plugin-codemod-optional-catch-binding/README.md

@@ -36,21 +36,21 @@ npm install --save-dev @babel/plugin-codemod-optional-catch-binding
 
 ```json
 {
-  "plugins": ["@babel/codemod-optional-catch-binding"]
+  "plugins": ["@babel/plugin-codemod-optional-catch-binding"]
 }
 ```
 
 ### Via CLI
 
 ```sh
-babel --plugins @babel/codemod-optional-catch-binding script.js
+babel --plugins @babel/plugin-codemod-optional-catch-binding script.js
 ```
 
 ### Via Node API
 
 ```javascript
 require("@babel/core").transform("code", {
-  plugins: ["@babel/codemod-optional-catch-binding"]
+  plugins: ["@babel/plugin-codemod-optional-catch-binding"]
 });
 ```
 

codemods/babel-plugin-codemod-optional-catch-binding/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/plugin-codemod-optional-catch-binding",
-  "version": "7.0.0-beta.32",
+  "version": "7.0.0-beta.36",
   "description": "Remove unused catch bindings",
   "repository": "https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-remove-unused-catch-binding",
   "license": "MIT",
@@ -9,13 +9,13 @@
     "@babel/plugin"
   ],
   "dependencies": {
-    "@babel/plugin-syntax-optional-catch-binding": "7.0.0-beta.32"
+    "@babel/plugin-syntax-optional-catch-binding": "7.0.0-beta.36"
   },
   "peerDependencies": {
-    "@babel/core": "7.0.0-beta.32"
+    "@babel/core": "7.0.0-beta.36"
   },
   "devDependencies": {
-    "@babel/core": "7.0.0-beta.32",
-    "@babel/helper-plugin-test-runner": "7.0.0-beta.32"
+    "@babel/core": "7.0.0-beta.36",
+    "@babel/helper-plugin-test-runner": "7.0.0-beta.36"
   }
 }

experimental/.eslintrc

@@ -1,6 +0,0 @@
-{
-  "rules": {
-    "prettier/prettier": ["error", { "trailingComma": "all" }],
-    "no-undefined-identifier": 2
-  }
-}

experimental/babel-preset-env/.eslintignore

@@ -1,6 +0,0 @@
-/lib
-debug-fixtures
-fixtures
-/data
-/flow-typed
-test/tmp

experimental/babel-preset-env/package.json

@@ -1,63 +0,0 @@
-{
-  "name": "@babel/preset-env",
-  "version": "7.0.0-beta.32",
-  "description": "A Babel preset for each environment.",
-  "author": "Henry Zhu <hi@henryzoo.com>",
-  "homepage": "https://babeljs.io/",
-  "license": "MIT",
-  "repository": "https://github.com/babel/babel/tree/master/experimental/babel-preset-env",
-  "main": "lib/index.js",
-  "scripts": {
-    "build-data": "node ./scripts/build-data.js"
-  },
-  "dependencies": {
-    "@babel/plugin-check-constants": "7.0.0-beta.32",
-    "@babel/plugin-proposal-async-generator-functions": "7.0.0-beta.32",
-    "@babel/plugin-proposal-object-rest-spread": "7.0.0-beta.32",
-    "@babel/plugin-proposal-optional-catch-binding": "7.0.0-beta.32",
-    "@babel/plugin-proposal-unicode-property-regex": "7.0.0-beta.32",
-    "@babel/plugin-syntax-async-generators": "7.0.0-beta.32",
-    "@babel/plugin-syntax-object-rest-spread": "7.0.0-beta.32",
-    "@babel/plugin-syntax-optional-catch-binding": "7.0.0-beta.32",
-    "@babel/plugin-transform-arrow-functions": "7.0.0-beta.32",
-    "@babel/plugin-transform-async-to-generator": "7.0.0-beta.32",
-    "@babel/plugin-transform-block-scoped-functions": "7.0.0-beta.32",
-    "@babel/plugin-transform-block-scoping": "7.0.0-beta.32",
-    "@babel/plugin-transform-classes": "7.0.0-beta.32",
-    "@babel/plugin-transform-computed-properties": "7.0.0-beta.32",
-    "@babel/plugin-transform-destructuring": "7.0.0-beta.32",
-    "@babel/plugin-transform-duplicate-keys": "7.0.0-beta.32",
-    "@babel/plugin-transform-exponentiation-operator": "7.0.0-beta.32",
-    "@babel/plugin-transform-for-of": "7.0.0-beta.32",
-    "@babel/plugin-transform-function-name": "7.0.0-beta.32",
-    "@babel/plugin-transform-literals": "7.0.0-beta.32",
-    "@babel/plugin-transform-modules-amd": "7.0.0-beta.32",
-    "@babel/plugin-transform-modules-commonjs": "7.0.0-beta.32",
-    "@babel/plugin-transform-modules-systemjs": "7.0.0-beta.32",
-    "@babel/plugin-transform-modules-umd": "7.0.0-beta.32",
-    "@babel/plugin-transform-new-target": "7.0.0-beta.32",
-    "@babel/plugin-transform-object-super": "7.0.0-beta.32",
-    "@babel/plugin-transform-parameters": "7.0.0-beta.32",
-    "@babel/plugin-transform-regenerator": "7.0.0-beta.32",
-    "@babel/plugin-transform-shorthand-properties": "7.0.0-beta.32",
-    "@babel/plugin-transform-spread": "7.0.0-beta.32",
-    "@babel/plugin-transform-sticky-regex": "7.0.0-beta.32",
-    "@babel/plugin-transform-template-literals": "7.0.0-beta.32",
-    "@babel/plugin-transform-typeof-symbol": "7.0.0-beta.32",
-    "@babel/plugin-transform-unicode-regex": "7.0.0-beta.32",
-    "browserslist": "^2.4.0",
-    "invariant": "^2.2.2",
-    "semver": "^5.3.0"
-  },
-  "peerDependencies": {
-    "@babel/core": "7.0.0-beta.32"
-  },
-  "devDependencies": {
-    "@babel/cli": "7.0.0-beta.32",
-    "@babel/core": "7.0.0-beta.32",
-    "@babel/helper-fixtures": "7.0.0-beta.32",
-    "@babel/helper-plugin-test-runner": "7.0.0-beta.32",
-    "compat-table": "kangax/compat-table#957f1ff15972e8fb2892a172f985e9af27bf1c75",
-    "electron-to-chromium": "^1.3.27"
-  }
-}

experimental/babel-preset-env/scripts/.eslintrc

@@ -1,5 +0,0 @@
-{
-    "rules": {
-      "prettier/prettier": ["error", { "trailingComma": "es5" }]
-    }
-  }

experimental/babel-preset-env/test/.eslintrc

@@ -1,8 +0,0 @@
-{
-  "env": {
-    "mocha": true
-  },
-  "rules": {
-    "max-len": 0
-  }
-}

experimental/babel-preset-env/test/fixtures/preset-options/include/expected.js

@@ -1,5 +0,0 @@
-"use strict";
-
-var _a = _interopRequireDefault(require("a"));
-
-function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

experimental/babel-preset-env/test/fixtures/preset-options/modules-false/actual.js

@@ -1 +0,0 @@
-import a from "a";

lerna.json

@@ -1,16 +1,16 @@
 {
   "lerna": "2.0.0-rc.4",
-  "version": "7.0.0-beta.32",
+  "version": "7.0.0-beta.36",
   "changelog": {
     "repo": "babel/babel",
     "labels": {
-      "Tag: Spec Compliancy": ":eyeglasses: Spec Compliancy",
-      "Tag: Breaking Change": ":boom: Breaking Change",
-      "Tag: New Feature": ":rocket: New Feature",
-      "Tag: Bug Fix": ":bug: Bug Fix",
-      "Tag: Polish": ":nail_care: Polish",
-      "Tag: Docs": ":memo: Documentation",
-      "Tag: Internal": ":house: Internal"
+      "PR: Spec Compliancy": ":eyeglasses: Spec Compliancy",
+      "PR: Breaking Change": ":boom: Breaking Change",
+      "PR: New Feature": ":rocket: New Feature",
+      "PR: Bug Fix": ":bug: Bug Fix",
+      "PR: Polish": ":nail_care: Polish",
+      "PR: Docs": ":memo: Documentation",
+      "PR: Internal": ":house: Internal"
     }
   },
   "cacheDir": ".changelog",
@@ -19,15 +19,13 @@
       "ignore": [
         "*.md",
         "test/**",
-        "codemods/**",
-        "experimental/**"
+        "codemods/**"
       ]
     }
   },
   "packages": [
     "packages/*",
-    "codemods/*",
-    "experimental/*"
+    "codemods/*"
   ],
   "npmClient": "yarn",
   "npmClientArgs": [

lib/types.js

@@ -82,7 +82,7 @@ declare class BabelNodeCallExpression extends BabelNode {
   callee: BabelNodeExpression;
   arguments: any;
   optional?: true | false;
-  typeParameters?: ?BabelNodeTypeParameterInstantiation;
+  typeParameters?: ?BabelNodeTypeParameterInstantiation | BabelNodeTSTypeParameterInstantiation;
 }
 
 declare class BabelNodeCatchClause extends BabelNode {
@@ -153,7 +153,7 @@ declare class BabelNodeFunctionDeclaration extends BabelNode {
   async?: boolean;
   declare?: boolean;
   returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop;
+  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop;
 }
 
 declare class BabelNodeFunctionExpression extends BabelNode {
@@ -164,7 +164,7 @@ declare class BabelNodeFunctionExpression extends BabelNode {
   generator?: boolean;
   async?: boolean;
   returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop;
+  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop;
 }
 
 declare class BabelNodeIdentifier extends BabelNode {
@@ -233,7 +233,7 @@ declare class BabelNodeNewExpression extends BabelNode {
   callee: BabelNodeExpression;
   arguments: any;
   optional?: true | false;
-  typeParameters?: ?BabelNodeTypeParameterInstantiation;
+  typeParameters?: ?BabelNodeTypeParameterInstantiation | BabelNodeTSTypeParameterInstantiation;
 }
 
 declare class BabelNodeProgram extends BabelNode {
@@ -260,7 +260,7 @@ declare class BabelNodeObjectMethod extends BabelNode {
   decorators?: any;
   generator?: boolean;
   returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop;
+  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop;
 }
 
 declare class BabelNodeObjectProperty extends BabelNode {
@@ -352,7 +352,7 @@ declare class BabelNodeWhileStatement extends BabelNode {
 
 declare class BabelNodeWithStatement extends BabelNode {
   type: "WithStatement";
-  object: any;
+  object: BabelNodeExpression;
   body: BabelNodeBlockStatement | BabelNodeStatement;
 }
 
@@ -379,7 +379,7 @@ declare class BabelNodeArrowFunctionExpression extends BabelNode {
   expression?: boolean;
   generator?: boolean;
   returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop;
+  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop;
 }
 
 declare class BabelNodeClassBody extends BabelNode {
@@ -396,8 +396,8 @@ declare class BabelNodeClassDeclaration extends BabelNode {
   abstract?: boolean;
   declare?: boolean;
   mixins?: any;
-  superTypeParameters?: ?BabelNodeTypeParameterInstantiation;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop;
+  superTypeParameters?: ?BabelNodeTypeParameterInstantiation | BabelNodeTSTypeParameterInstantiation;
+  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop;
 }
 
 declare class BabelNodeClassExpression extends BabelNode {
@@ -407,8 +407,8 @@ declare class BabelNodeClassExpression extends BabelNode {
   body: BabelNodeClassBody;
   decorators?: any;
   mixins?: any;
-  superTypeParameters?: ?BabelNodeTypeParameterInstantiation;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop;
+  superTypeParameters?: ?BabelNodeTypeParameterInstantiation | BabelNodeTSTypeParameterInstantiation;
+  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop;
 }
 
 declare class BabelNodeExportAllDeclaration extends BabelNode {
@@ -485,7 +485,7 @@ declare class BabelNodeClassMethod extends BabelNode {
   generator?: boolean;
   optional?: boolean;
   returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop;
+  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop;
 }
 
 declare class BabelNodeObjectPattern extends BabelNode {
@@ -800,7 +800,7 @@ declare class BabelNodeVoidTypeAnnotation extends BabelNode {
 declare class BabelNodeJSXAttribute extends BabelNode {
   type: "JSXAttribute";
   name: BabelNodeJSXIdentifier | BabelNodeJSXNamespacedName;
-  value?: ?BabelNodeJSXElement | BabelNodeStringLiteral | BabelNodeJSXExpressionContainer;
+  value?: ?BabelNodeJSXElement | BabelNodeJSXFragment | BabelNodeStringLiteral | BabelNodeJSXExpressionContainer;
 }
 
 declare class BabelNodeJSXClosingElement extends BabelNode {
@@ -864,6 +864,21 @@ declare class BabelNodeJSXText extends BabelNode {
   value: string;
 }
 
+declare class BabelNodeJSXFragment extends BabelNode {
+  type: "JSXFragment";
+  openingFragment: BabelNodeJSXOpeningFragment;
+  closingFragment: BabelNodeJSXClosingFragment;
+  children: any;
+}
+
+declare class BabelNodeJSXOpeningFragment extends BabelNode {
+  type: "JSXOpeningFragment";
+}
+
+declare class BabelNodeJSXClosingFragment extends BabelNode {
+  type: "JSXClosingFragment";
+}
+
 declare class BabelNodeNoop extends BabelNode {
   type: "Noop";
 }
@@ -931,9 +946,9 @@ declare class BabelNodeTSParameterProperty extends BabelNode {
 declare class BabelNodeTSDeclareFunction extends BabelNode {
   type: "TSDeclareFunction";
   id?: ?BabelNodeIdentifier;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop;
+  typeParameters?: ?BabelNodeTSTypeParameterDeclaration | BabelNodeNoop;
   params: any;
-  returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop;
+  returnType?: ?BabelNodeTSTypeAnnotation | BabelNodeNoop;
   async?: boolean;
   declare?: boolean;
   generator?: boolean;
@@ -943,9 +958,9 @@ declare class BabelNodeTSDeclareMethod extends BabelNode {
   type: "TSDeclareMethod";
   decorators?: any;
   key: any;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop;
+  typeParameters?: ?BabelNodeTSTypeParameterDeclaration | BabelNodeNoop;
   params: any;
-  returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop;
+  returnType?: ?BabelNodeTSTypeAnnotation | BabelNodeNoop;
   abstract?: boolean;
   access?: any;
   accessibility?: any;
@@ -964,14 +979,14 @@ declare class BabelNodeTSQualifiedName extends BabelNode {
 
 declare class BabelNodeTSCallSignatureDeclaration extends BabelNode {
   type: "TSCallSignatureDeclaration";
-  typeParameters?: ?BabelNodeTypeParameterDeclaration;
+  typeParameters?: ?BabelNodeTSTypeParameterDeclaration;
   parameters?: any;
   typeAnnotation?: ?BabelNodeTSTypeAnnotation;
 }
 
 declare class BabelNodeTSConstructSignatureDeclaration extends BabelNode {
   type: "TSConstructSignatureDeclaration";
-  typeParameters?: ?BabelNodeTypeParameterDeclaration;
+  typeParameters?: ?BabelNodeTSTypeParameterDeclaration;
   parameters?: any;
   typeAnnotation?: ?BabelNodeTSTypeAnnotation;
 }
@@ -989,7 +1004,7 @@ declare class BabelNodeTSPropertySignature extends BabelNode {
 declare class BabelNodeTSMethodSignature extends BabelNode {
   type: "TSMethodSignature";
   key: BabelNodeExpression;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration;
+  typeParameters?: ?BabelNodeTSTypeParameterDeclaration;
   parameters?: any;
   typeAnnotation?: ?BabelNodeTSTypeAnnotation;
   computed?: boolean;
@@ -1049,14 +1064,14 @@ declare class BabelNodeTSThisType extends BabelNode {
 
 declare class BabelNodeTSFunctionType extends BabelNode {
   type: "TSFunctionType";
-  typeParameters?: ?BabelNodeTypeParameterDeclaration;
+  typeParameters?: ?BabelNodeTSTypeParameterDeclaration;
   typeAnnotation?: ?BabelNodeTSTypeAnnotation;
   parameters?: any;
 }
 
 declare class BabelNodeTSConstructorType extends BabelNode {
   type: "TSConstructorType";
-  typeParameters?: ?BabelNodeTypeParameterDeclaration;
+  typeParameters?: ?BabelNodeTSTypeParameterDeclaration;
   typeAnnotation?: ?BabelNodeTSTypeAnnotation;
   parameters?: any;
 }
@@ -1064,7 +1079,7 @@ declare class BabelNodeTSConstructorType extends BabelNode {
 declare class BabelNodeTSTypeReference extends BabelNode {
   type: "TSTypeReference";
   typeName: BabelNodeTSEntityName;
-  typeParameters?: ?BabelNodeTypeParameterInstantiation;
+  typeParameters?: ?BabelNodeTSTypeParameterInstantiation;
 }
 
 declare class BabelNodeTSTypePredicate extends BabelNode {
@@ -1122,7 +1137,7 @@ declare class BabelNodeTSIndexedAccessType extends BabelNode {
 
 declare class BabelNodeTSMappedType extends BabelNode {
   type: "TSMappedType";
-  typeParameter: BabelNodeTypeParameter;
+  typeParameter: BabelNodeTSTypeParameter;
   typeAnnotation?: ?BabelNodeTSType;
   optional?: boolean;
   readonly?: boolean;
@@ -1136,13 +1151,13 @@ declare class BabelNodeTSLiteralType extends BabelNode {
 declare class BabelNodeTSExpressionWithTypeArguments extends BabelNode {
   type: "TSExpressionWithTypeArguments";
   expression: BabelNodeTSEntityName;
-  typeParameters?: ?BabelNodeTypeParameterInstantiation;
+  typeParameters?: ?BabelNodeTSTypeParameterInstantiation;
 }
 
 declare class BabelNodeTSInterfaceDeclaration extends BabelNode {
   type: "TSInterfaceDeclaration";
   id: BabelNodeIdentifier;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration;
+  typeParameters?: ?BabelNodeTSTypeParameterDeclaration;
   body: BabelNodeTSInterfaceBody;
   declare?: boolean;
 }
@@ -1155,7 +1170,7 @@ declare class BabelNodeTSInterfaceBody extends BabelNode {
 declare class BabelNodeTSTypeAliasDeclaration extends BabelNode {
   type: "TSTypeAliasDeclaration";
   id: BabelNodeIdentifier;
-  typeParameters?: ?BabelNodeTypeParameterDeclaration;
+  typeParameters?: ?BabelNodeTSTypeParameterDeclaration;
   typeAnnotation: BabelNodeTSType;
   declare?: boolean;
 }
@@ -1247,7 +1262,7 @@ declare class BabelNodeTSTypeParameter extends BabelNode {
   name?: string;
 }
 
-type BabelNodeExpression = BabelNodeArrayExpression | BabelNodeAssignmentExpression | BabelNodeBinaryExpression | BabelNodeCallExpression | BabelNodeConditionalExpression | BabelNodeFunctionExpression | BabelNodeIdentifier | BabelNodeStringLiteral | BabelNodeNumericLiteral | BabelNodeNullLiteral | BabelNodeBooleanLiteral | BabelNodeRegExpLiteral | BabelNodeLogicalExpression | BabelNodeMemberExpression | BabelNodeNewExpression | BabelNodeObjectExpression | BabelNodeSequenceExpression | BabelNodeThisExpression | BabelNodeUnaryExpression | BabelNodeUpdateExpression | BabelNodeArrowFunctionExpression | BabelNodeClassExpression | BabelNodeMetaProperty | BabelNodeSuper | BabelNodeTaggedTemplateExpression | BabelNodeTemplateLiteral | BabelNodeYieldExpression | BabelNodeTypeCastExpression | BabelNodeJSXElement | BabelNodeJSXEmptyExpression | BabelNodeJSXIdentifier | BabelNodeJSXMemberExpression | BabelNodeParenthesizedExpression | BabelNodeAwaitExpression | BabelNodeBindExpression | BabelNodeImport | BabelNodeDoExpression | BabelNodeTSAsExpression | BabelNodeTSTypeAssertion | BabelNodeTSNonNullExpression;
+type BabelNodeExpression = BabelNodeArrayExpression | BabelNodeAssignmentExpression | BabelNodeBinaryExpression | BabelNodeCallExpression | BabelNodeConditionalExpression | BabelNodeFunctionExpression | BabelNodeIdentifier | BabelNodeStringLiteral | BabelNodeNumericLiteral | BabelNodeNullLiteral | BabelNodeBooleanLiteral | BabelNodeRegExpLiteral | BabelNodeLogicalExpression | BabelNodeMemberExpression | BabelNodeNewExpression | BabelNodeObjectExpression | BabelNodeSequenceExpression | BabelNodeThisExpression | BabelNodeUnaryExpression | BabelNodeUpdateExpression | BabelNodeArrowFunctionExpression | BabelNodeClassExpression | BabelNodeMetaProperty | BabelNodeSuper | BabelNodeTaggedTemplateExpression | BabelNodeTemplateLiteral | BabelNodeYieldExpression | BabelNodeTypeCastExpression | BabelNodeJSXElement | BabelNodeJSXFragment | BabelNodeParenthesizedExpression | BabelNodeAwaitExpression | BabelNodeBindExpression | BabelNodeImport | BabelNodeDoExpression | BabelNodeTSAsExpression | BabelNodeTSTypeAssertion | BabelNodeTSNonNullExpression;
 type BabelNodeBinary = BabelNodeBinaryExpression | BabelNodeLogicalExpression;
 type BabelNodeScopable = BabelNodeBlockStatement | BabelNodeCatchClause | BabelNodeDoWhileStatement | BabelNodeForInStatement | BabelNodeForStatement | BabelNodeFunctionDeclaration | BabelNodeFunctionExpression | BabelNodeProgram | BabelNodeObjectMethod | BabelNodeSwitchStatement | BabelNodeWhileStatement | BabelNodeArrowFunctionExpression | BabelNodeClassDeclaration | BabelNodeClassExpression | BabelNodeForOfStatement | BabelNodeClassMethod;
 type BabelNodeBlockParent = BabelNodeBlockStatement | BabelNodeCatchClause | BabelNodeDoWhileStatement | BabelNodeForInStatement | BabelNodeForStatement | BabelNodeFunctionDeclaration | BabelNodeFunctionExpression | BabelNodeProgram | BabelNodeObjectMethod | BabelNodeSwitchStatement | BabelNodeWhileStatement | BabelNodeArrowFunctionExpression | BabelNodeForOfStatement | BabelNodeClassMethod;
@@ -1269,7 +1284,7 @@ type BabelNodePatternLike = BabelNodeIdentifier | BabelNodeRestElement | BabelNo
 type BabelNodeLVal = BabelNodeIdentifier | BabelNodeMemberExpression | BabelNodeRestElement | BabelNodeAssignmentPattern | BabelNodeArrayPattern | BabelNodeObjectPattern | BabelNodeTSParameterProperty;
 type BabelNodeTSEntityName = BabelNodeIdentifier | BabelNodeTSQualifiedName;
 type BabelNodeLiteral = BabelNodeStringLiteral | BabelNodeNumericLiteral | BabelNodeNullLiteral | BabelNodeBooleanLiteral | BabelNodeRegExpLiteral | BabelNodeTemplateLiteral;
-type BabelNodeImmutable = BabelNodeStringLiteral | BabelNodeNumericLiteral | BabelNodeNullLiteral | BabelNodeBooleanLiteral | BabelNodeJSXAttribute | BabelNodeJSXClosingElement | BabelNodeJSXElement | BabelNodeJSXExpressionContainer | BabelNodeJSXSpreadChild | BabelNodeJSXOpeningElement | BabelNodeJSXText;
+type BabelNodeImmutable = BabelNodeStringLiteral | BabelNodeNumericLiteral | BabelNodeNullLiteral | BabelNodeBooleanLiteral | BabelNodeJSXAttribute | BabelNodeJSXClosingElement | BabelNodeJSXElement | BabelNodeJSXExpressionContainer | BabelNodeJSXSpreadChild | BabelNodeJSXOpeningElement | BabelNodeJSXText | BabelNodeJSXFragment | BabelNodeJSXOpeningFragment | BabelNodeJSXClosingFragment;
 type BabelNodeUserWhitespacable = BabelNodeObjectMethod | BabelNodeObjectProperty | BabelNodeObjectTypeCallProperty | BabelNodeObjectTypeIndexer | BabelNodeObjectTypeProperty | BabelNodeObjectTypeSpreadProperty;
 type BabelNodeMethod = BabelNodeObjectMethod | BabelNodeClassMethod;
 type BabelNodeObjectMember = BabelNodeObjectMethod | BabelNodeObjectProperty;
@@ -1284,7 +1299,7 @@ type BabelNodeFlow = BabelNodeAnyTypeAnnotation | BabelNodeArrayTypeAnnotation |
 type BabelNodeFlowBaseAnnotation = BabelNodeAnyTypeAnnotation | BabelNodeBooleanTypeAnnotation | BabelNodeNullLiteralTypeAnnotation | BabelNodeMixedTypeAnnotation | BabelNodeEmptyTypeAnnotation | BabelNodeNumberTypeAnnotation | BabelNodeStringTypeAnnotation | BabelNodeThisTypeAnnotation | BabelNodeVoidTypeAnnotation;
 type BabelNodeFlowDeclaration = BabelNodeDeclareClass | BabelNodeDeclareFunction | BabelNodeDeclareInterface | BabelNodeDeclareModule | BabelNodeDeclareModuleExports | BabelNodeDeclareTypeAlias | BabelNodeDeclareOpaqueType | BabelNodeDeclareVariable | BabelNodeDeclareExportDeclaration | BabelNodeDeclareExportAllDeclaration | BabelNodeInterfaceDeclaration | BabelNodeOpaqueType | BabelNodeTypeAlias;
 type BabelNodeFlowPredicate = BabelNodeDeclaredPredicate | BabelNodeInferredPredicate;
-type BabelNodeJSX = BabelNodeJSXAttribute | BabelNodeJSXClosingElement | BabelNodeJSXElement | BabelNodeJSXEmptyExpression | BabelNodeJSXExpressionContainer | BabelNodeJSXSpreadChild | BabelNodeJSXIdentifier | BabelNodeJSXMemberExpression | BabelNodeJSXNamespacedName | BabelNodeJSXOpeningElement | BabelNodeJSXSpreadAttribute | BabelNodeJSXText;
+type BabelNodeJSX = BabelNodeJSXAttribute | BabelNodeJSXClosingElement | BabelNodeJSXElement | BabelNodeJSXEmptyExpression | BabelNodeJSXExpressionContainer | BabelNodeJSXSpreadChild | BabelNodeJSXIdentifier | BabelNodeJSXMemberExpression | BabelNodeJSXNamespacedName | BabelNodeJSXOpeningElement | BabelNodeJSXSpreadAttribute | BabelNodeJSXText | BabelNodeJSXFragment | BabelNodeJSXOpeningFragment | BabelNodeJSXClosingFragment;
 type BabelNodeTSTypeElement = BabelNodeTSCallSignatureDeclaration | BabelNodeTSConstructSignatureDeclaration | BabelNodeTSPropertySignature | BabelNodeTSMethodSignature | BabelNodeTSIndexSignature;
 type BabelNodeTSType = BabelNodeTSAnyKeyword | BabelNodeTSNumberKeyword | BabelNodeTSObjectKeyword | BabelNodeTSBooleanKeyword | BabelNodeTSStringKeyword | BabelNodeTSSymbolKeyword | BabelNodeTSVoidKeyword | BabelNodeTSUndefinedKeyword | BabelNodeTSNullKeyword | BabelNodeTSNeverKeyword | BabelNodeTSThisType | BabelNodeTSFunctionType | BabelNodeTSConstructorType | BabelNodeTSTypeReference | BabelNodeTSTypePredicate | BabelNodeTSTypeQuery | BabelNodeTSTypeLiteral | BabelNodeTSArrayType | BabelNodeTSTupleType | BabelNodeTSUnionType | BabelNodeTSIntersectionType | BabelNodeTSParenthesizedType | BabelNodeTSTypeOperator | BabelNodeTSIndexedAccessType | BabelNodeTSMappedType | BabelNodeTSLiteralType | BabelNodeTSExpressionWithTypeArguments;
 
@@ -1296,7 +1311,7 @@ declare module "@babel/types" {
   declare function directiveLiteral(value: string): BabelNodeDirectiveLiteral;
   declare function blockStatement(body: any, directives?: any): BabelNodeBlockStatement;
   declare function breakStatement(label?: ?BabelNodeIdentifier): BabelNodeBreakStatement;
-  declare function callExpression(callee: BabelNodeExpression, _arguments: any, optional?: true | false, typeParameters?: ?BabelNodeTypeParameterInstantiation): BabelNodeCallExpression;
+  declare function callExpression(callee: BabelNodeExpression, _arguments: any, optional?: true | false, typeParameters?: ?BabelNodeTypeParameterInstantiation | BabelNodeTSTypeParameterInstantiation): BabelNodeCallExpression;
   declare function catchClause(param?: ?BabelNodeIdentifier, body: BabelNodeBlockStatement): BabelNodeCatchClause;
   declare function conditionalExpression(test: BabelNodeExpression, consequent: BabelNodeExpression, alternate: BabelNodeExpression): BabelNodeConditionalExpression;
   declare function continueStatement(label?: ?BabelNodeIdentifier): BabelNodeContinueStatement;
@@ -1307,8 +1322,8 @@ declare module "@babel/types" {
   declare function file(program: BabelNodeProgram, comments: any, tokens: any): BabelNodeFile;
   declare function forInStatement(left: BabelNodeVariableDeclaration | BabelNodeLVal, right: BabelNodeExpression, body: BabelNodeStatement): BabelNodeForInStatement;
   declare function forStatement(init?: ?BabelNodeVariableDeclaration | BabelNodeExpression, test?: ?BabelNodeExpression, update?: ?BabelNodeExpression, body: BabelNodeStatement): BabelNodeForStatement;
-  declare function functionDeclaration(id?: ?BabelNodeIdentifier, params: any, body: BabelNodeBlockStatement, generator?: boolean, async?: boolean, declare?: boolean, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop): BabelNodeFunctionDeclaration;
-  declare function functionExpression(id?: ?BabelNodeIdentifier, params: any, body: BabelNodeBlockStatement, generator?: boolean, async?: boolean, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop): BabelNodeFunctionExpression;
+  declare function functionDeclaration(id?: ?BabelNodeIdentifier, params: any, body: BabelNodeBlockStatement, generator?: boolean, async?: boolean, declare?: boolean, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop): BabelNodeFunctionDeclaration;
+  declare function functionExpression(id?: ?BabelNodeIdentifier, params: any, body: BabelNodeBlockStatement, generator?: boolean, async?: boolean, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop): BabelNodeFunctionExpression;
   declare function identifier(name: any, decorators?: any, optional?: boolean, typeAnnotation?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop): BabelNodeIdentifier;
   declare function ifStatement(test: BabelNodeExpression, consequent: BabelNodeStatement, alternate?: ?BabelNodeStatement): BabelNodeIfStatement;
   declare function labeledStatement(label: BabelNodeIdentifier, body: BabelNodeStatement): BabelNodeLabeledStatement;
@@ -1319,10 +1334,10 @@ declare module "@babel/types" {
   declare function regExpLiteral(pattern: string, flags?: string): BabelNodeRegExpLiteral;
   declare function logicalExpression(operator: "||" | "&&" | "??", left: BabelNodeExpression, right: BabelNodeExpression): BabelNodeLogicalExpression;
   declare function memberExpression(object: BabelNodeExpression, property: any, computed?: boolean, optional?: true | false): BabelNodeMemberExpression;
-  declare function newExpression(callee: BabelNodeExpression, _arguments: any, optional?: true | false, typeParameters?: ?BabelNodeTypeParameterInstantiation): BabelNodeNewExpression;
+  declare function newExpression(callee: BabelNodeExpression, _arguments: any, optional?: true | false, typeParameters?: ?BabelNodeTypeParameterInstantiation | BabelNodeTSTypeParameterInstantiation): BabelNodeNewExpression;
   declare function program(body: any, directives?: any, sourceType?: "script" | "module", sourceFile?: string): BabelNodeProgram;
   declare function objectExpression(properties: any): BabelNodeObjectExpression;
-  declare function objectMethod(kind?: any, key: any, params: any, body: BabelNodeBlockStatement, computed?: boolean, async?: boolean, decorators?: any, generator?: boolean, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop): BabelNodeObjectMethod;
+  declare function objectMethod(kind?: any, key: any, params: any, body: BabelNodeBlockStatement, computed?: boolean, async?: boolean, decorators?: any, generator?: boolean, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop): BabelNodeObjectMethod;
   declare function objectProperty(key: any, value: BabelNodeExpression | BabelNodePatternLike, computed?: boolean, shorthand?: boolean, decorators?: any): BabelNodeObjectProperty;
   declare function restElement(argument: BabelNodeLVal, decorators?: any, typeAnnotation?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop): BabelNodeRestElement;
   declare function returnStatement(argument?: ?BabelNodeExpression): BabelNodeReturnStatement;
@@ -1337,13 +1352,13 @@ declare module "@babel/types" {
   declare function variableDeclaration(kind: any, declarations: any, declare?: boolean): BabelNodeVariableDeclaration;
   declare function variableDeclarator(id: BabelNodeLVal, init?: ?BabelNodeExpression): BabelNodeVariableDeclarator;
   declare function whileStatement(test: BabelNodeExpression, body: BabelNodeBlockStatement | BabelNodeStatement): BabelNodeWhileStatement;
-  declare function withStatement(object: any, body: BabelNodeBlockStatement | BabelNodeStatement): BabelNodeWithStatement;
+  declare function withStatement(object: BabelNodeExpression, body: BabelNodeBlockStatement | BabelNodeStatement): BabelNodeWithStatement;
   declare function assignmentPattern(left: BabelNodeIdentifier | BabelNodeObjectPattern | BabelNodeArrayPattern, right: BabelNodeExpression, decorators?: any, typeAnnotation?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop): BabelNodeAssignmentPattern;
   declare function arrayPattern(elements: any, decorators?: any, typeAnnotation?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop): BabelNodeArrayPattern;
-  declare function arrowFunctionExpression(params: any, body: BabelNodeBlockStatement | BabelNodeExpression, async?: boolean, expression?: boolean, generator?: boolean, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop): BabelNodeArrowFunctionExpression;
+  declare function arrowFunctionExpression(params: any, body: BabelNodeBlockStatement | BabelNodeExpression, async?: boolean, expression?: boolean, generator?: boolean, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop): BabelNodeArrowFunctionExpression;
   declare function classBody(body: any): BabelNodeClassBody;
-  declare function classDeclaration(id?: ?BabelNodeIdentifier, superClass?: ?BabelNodeExpression, body: BabelNodeClassBody, decorators?: any, abstract?: boolean, declare?: boolean, _implements?: any, mixins?: any, superTypeParameters?: ?BabelNodeTypeParameterInstantiation, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop): BabelNodeClassDeclaration;
-  declare function classExpression(id?: ?BabelNodeIdentifier, superClass?: ?BabelNodeExpression, body: BabelNodeClassBody, decorators?: any, _implements?: any, mixins?: any, superTypeParameters?: ?BabelNodeTypeParameterInstantiation, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop): BabelNodeClassExpression;
+  declare function classDeclaration(id?: ?BabelNodeIdentifier, superClass?: ?BabelNodeExpression, body: BabelNodeClassBody, decorators?: any, abstract?: boolean, declare?: boolean, _implements?: any, mixins?: any, superTypeParameters?: ?BabelNodeTypeParameterInstantiation | BabelNodeTSTypeParameterInstantiation, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop): BabelNodeClassDeclaration;
+  declare function classExpression(id?: ?BabelNodeIdentifier, superClass?: ?BabelNodeExpression, body: BabelNodeClassBody, decorators?: any, _implements?: any, mixins?: any, superTypeParameters?: ?BabelNodeTypeParameterInstantiation | BabelNodeTSTypeParameterInstantiation, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop): BabelNodeClassExpression;
   declare function exportAllDeclaration(source: BabelNodeStringLiteral): BabelNodeExportAllDeclaration;
   declare function exportDefaultDeclaration(declaration: BabelNodeFunctionDeclaration | BabelNodeTSDeclareFunction | BabelNodeClassDeclaration | BabelNodeExpression): BabelNodeExportDefaultDeclaration;
   declare function exportNamedDeclaration(declaration?: ?BabelNodeDeclaration, specifiers: any, source?: ?BabelNodeStringLiteral): BabelNodeExportNamedDeclaration;
@@ -1354,7 +1369,7 @@ declare module "@babel/types" {
   declare function importNamespaceSpecifier(local: BabelNodeIdentifier): BabelNodeImportNamespaceSpecifier;
   declare function importSpecifier(local: BabelNodeIdentifier, imported: BabelNodeIdentifier, importKind?: null | "type" | "typeof"): BabelNodeImportSpecifier;
   declare function metaProperty(meta: BabelNodeIdentifier, property: BabelNodeIdentifier): BabelNodeMetaProperty;
-  declare function classMethod(kind?: any, key: any, params: any, body: BabelNodeBlockStatement, computed?: boolean, _static?: boolean, abstract?: boolean, access?: any, accessibility?: any, async?: boolean, decorators?: any, generator?: boolean, optional?: boolean, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop): BabelNodeClassMethod;
+  declare function classMethod(kind?: any, key: any, params: any, body: BabelNodeBlockStatement, computed?: boolean, _static?: boolean, abstract?: boolean, access?: any, accessibility?: any, async?: boolean, decorators?: any, generator?: boolean, optional?: boolean, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeTSTypeParameterDeclaration | BabelNodeNoop): BabelNodeClassMethod;
   declare function objectPattern(properties: any, decorators?: any, typeAnnotation?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop): BabelNodeObjectPattern;
   declare function spreadElement(argument: BabelNodeExpression): BabelNodeSpreadElement;
   declare function taggedTemplateExpression(tag: BabelNodeExpression, quasi: BabelNodeTemplateLiteral): BabelNodeTaggedTemplateExpression;
@@ -1411,7 +1426,7 @@ declare module "@babel/types" {
   declare function typeParameterInstantiation(params: any): BabelNodeTypeParameterInstantiation;
   declare function unionTypeAnnotation(types: any): BabelNodeUnionTypeAnnotation;
   declare function voidTypeAnnotation(): BabelNodeVoidTypeAnnotation;
-  declare function jSXAttribute(name: BabelNodeJSXIdentifier | BabelNodeJSXNamespacedName, value?: ?BabelNodeJSXElement | BabelNodeStringLiteral | BabelNodeJSXExpressionContainer): BabelNodeJSXAttribute;
+  declare function jSXAttribute(name: BabelNodeJSXIdentifier | BabelNodeJSXNamespacedName, value?: ?BabelNodeJSXElement | BabelNodeJSXFragment | BabelNodeStringLiteral | BabelNodeJSXExpressionContainer): BabelNodeJSXAttribute;
   declare function jSXClosingElement(name: BabelNodeJSXIdentifier | BabelNodeJSXMemberExpression): BabelNodeJSXClosingElement;
   declare function jSXElement(openingElement: BabelNodeJSXOpeningElement, closingElement?: ?BabelNodeJSXClosingElement, children: any, selfClosing: any): BabelNodeJSXElement;
   declare function jSXEmptyExpression(): BabelNodeJSXEmptyExpression;
@@ -1423,6 +1438,9 @@ declare module "@babel/types" {
   declare function jSXOpeningElement(name: BabelNodeJSXIdentifier | BabelNodeJSXMemberExpression, attributes: any, selfClosing?: boolean): BabelNodeJSXOpeningElement;
   declare function jSXSpreadAttribute(argument: BabelNodeExpression): BabelNodeJSXSpreadAttribute;
   declare function jSXText(value: string): BabelNodeJSXText;
+  declare function jSXFragment(openingFragment: BabelNodeJSXOpeningFragment, closingFragment: BabelNodeJSXClosingFragment, children: any): BabelNodeJSXFragment;
+  declare function jSXOpeningFragment(): BabelNodeJSXOpeningFragment;
+  declare function jSXClosingFragment(): BabelNodeJSXClosingFragment;
   declare function noop(): BabelNodeNoop;
   declare function parenthesizedExpression(expression: BabelNodeExpression): BabelNodeParenthesizedExpression;
   declare function awaitExpression(argument: BabelNodeExpression): BabelNodeAwaitExpression;
@@ -1433,13 +1451,13 @@ declare module "@babel/types" {
   declare function exportDefaultSpecifier(exported: BabelNodeIdentifier): BabelNodeExportDefaultSpecifier;
   declare function exportNamespaceSpecifier(exported: BabelNodeIdentifier): BabelNodeExportNamespaceSpecifier;
   declare function tSParameterProperty(parameter: BabelNodeIdentifier | BabelNodeAssignmentPattern, accessibility?: "public" | "private" | "protected", readonly?: boolean): BabelNodeTSParameterProperty;
-  declare function tSDeclareFunction(id?: ?BabelNodeIdentifier, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop, params: any, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, async?: boolean, declare?: boolean, generator?: boolean): BabelNodeTSDeclareFunction;
-  declare function tSDeclareMethod(decorators?: any, key: any, typeParameters?: ?BabelNodeTypeParameterDeclaration | BabelNodeNoop, params: any, returnType?: ?BabelNodeTypeAnnotation | BabelNodeTSTypeAnnotation | BabelNodeNoop, abstract?: boolean, access?: any, accessibility?: any, async?: boolean, computed?: boolean, generator?: boolean, kind?: any, optional?: boolean, _static?: boolean): BabelNodeTSDeclareMethod;
+  declare function tSDeclareFunction(id?: ?BabelNodeIdentifier, typeParameters?: ?BabelNodeTSTypeParameterDeclaration | BabelNodeNoop, params: any, returnType?: ?BabelNodeTSTypeAnnotation | BabelNodeNoop, async?: boolean, declare?: boolean, generator?: boolean): BabelNodeTSDeclareFunction;
+  declare function tSDeclareMethod(decorators?: any, key: any, typeParameters?: ?BabelNodeTSTypeParameterDeclaration | BabelNodeNoop, params: any, returnType?: ?BabelNodeTSTypeAnnotation | BabelNodeNoop, abstract?: boolean, access?: any, accessibility?: any, async?: boolean, computed?: boolean, generator?: boolean, kind?: any, optional?: boolean, _static?: boolean): BabelNodeTSDeclareMethod;
   declare function tSQualifiedName(left: BabelNodeTSEntityName, right: BabelNodeIdentifier): BabelNodeTSQualifiedName;
-  declare function tSCallSignatureDeclaration(typeParameters?: ?BabelNodeTypeParameterDeclaration, parameters?: any, typeAnnotation?: ?BabelNodeTSTypeAnnotation): BabelNodeTSCallSignatureDeclaration;
-  declare function tSConstructSignatureDeclaration(typeParameters?: ?BabelNodeTypeParameterDeclaration, parameters?: any, typeAnnotation?: ?BabelNodeTSTypeAnnotation): BabelNodeTSConstructSignatureDeclaration;
+  declare function tSCallSignatureDeclaration(typeParameters?: ?BabelNodeTSTypeParameterDeclaration, parameters?: any, typeAnnotation?: ?BabelNodeTSTypeAnnotation): BabelNodeTSCallSignatureDeclaration;
+  declare function tSConstructSignatureDeclaration(typeParameters?: ?BabelNodeTSTypeParameterDeclaration, parameters?: any, typeAnnotation?: ?BabelNodeTSTypeAnnotation): BabelNodeTSConstructSignatureDeclaration;
   declare function tSPropertySignature(key: BabelNodeExpression, typeAnnotation?: ?BabelNodeTSTypeAnnotation, initializer?: ?BabelNodeExpression, computed?: boolean, optional?: boolean, readonly?: boolean): BabelNodeTSPropertySignature;
-  declare function tSMethodSignature(key: BabelNodeExpression, typeParameters?: ?BabelNodeTypeParameterDeclaration, parameters?: any, typeAnnotation?: ?BabelNodeTSTypeAnnotation, computed?: boolean, optional?: boolean): BabelNodeTSMethodSignature;
+  declare function tSMethodSignature(key: BabelNodeExpression, typeParameters?: ?BabelNodeTSTypeParameterDeclaration, parameters?: any, typeAnnotation?: ?BabelNodeTSTypeAnnotation, computed?: boolean, optional?: boolean): BabelNodeTSMethodSignature;
   declare function tSIndexSignature(parameters: any, typeAnnotation?: ?BabelNodeTSTypeAnnotation, readonly?: boolean): BabelNodeTSIndexSignature;
   declare function tSAnyKeyword(): BabelNodeTSAnyKeyword;
   declare function tSNumberKeyword(): BabelNodeTSNumberKeyword;
@@ -1452,9 +1470,9 @@ declare module "@babel/types" {
   declare function tSNullKeyword(): BabelNodeTSNullKeyword;
   declare function tSNeverKeyword(): BabelNodeTSNeverKeyword;
   declare function tSThisType(): BabelNodeTSThisType;
-  declare function tSFunctionType(typeParameters?: ?BabelNodeTypeParameterDeclaration, typeAnnotation?: ?BabelNodeTSTypeAnnotation, parameters?: any): BabelNodeTSFunctionType;
-  declare function tSConstructorType(typeParameters?: ?BabelNodeTypeParameterDeclaration, typeAnnotation?: ?BabelNodeTSTypeAnnotation, parameters?: any): BabelNodeTSConstructorType;
-  declare function tSTypeReference(typeName: BabelNodeTSEntityName, typeParameters?: ?BabelNodeTypeParameterInstantiation): BabelNodeTSTypeReference;
+  declare function tSFunctionType(typeParameters?: ?BabelNodeTSTypeParameterDeclaration, typeAnnotation?: ?BabelNodeTSTypeAnnotation, parameters?: any): BabelNodeTSFunctionType;
+  declare function tSConstructorType(typeParameters?: ?BabelNodeTSTypeParameterDeclaration, typeAnnotation?: ?BabelNodeTSTypeAnnotation, parameters?: any): BabelNodeTSConstructorType;
+  declare function tSTypeReference(typeName: BabelNodeTSEntityName, typeParameters?: ?BabelNodeTSTypeParameterInstantiation): BabelNodeTSTypeReference;
   declare function tSTypePredicate(parameterName: BabelNodeIdentifier | BabelNodeTSThisType, typeAnnotation: BabelNodeTSTypeAnnotation): BabelNodeTSTypePredicate;
   declare function tSTypeQuery(exprName: BabelNodeTSEntityName): BabelNodeTSTypeQuery;
   declare function tSTypeLiteral(members: any): BabelNodeTSTypeLiteral;
@@ -1465,12 +1483,12 @@ declare module "@babel/types" {
   declare function tSParenthesizedType(typeAnnotation: BabelNodeTSType): BabelNodeTSParenthesizedType;
   declare function tSTypeOperator(typeAnnotation: BabelNodeTSType, operator?: string): BabelNodeTSTypeOperator;
   declare function tSIndexedAccessType(objectType: BabelNodeTSType, indexType: BabelNodeTSType): BabelNodeTSIndexedAccessType;
-  declare function tSMappedType(typeParameter: BabelNodeTypeParameter, typeAnnotation?: ?BabelNodeTSType, optional?: boolean, readonly?: boolean): BabelNodeTSMappedType;
+  declare function tSMappedType(typeParameter: BabelNodeTSTypeParameter, typeAnnotation?: ?BabelNodeTSType, optional?: boolean, readonly?: boolean): BabelNodeTSMappedType;
   declare function tSLiteralType(literal: BabelNodeNumericLiteral | BabelNodeStringLiteral | BabelNodeBooleanLiteral): BabelNodeTSLiteralType;
-  declare function tSExpressionWithTypeArguments(expression: BabelNodeTSEntityName, typeParameters?: ?BabelNodeTypeParameterInstantiation): BabelNodeTSExpressionWithTypeArguments;
-  declare function tSInterfaceDeclaration(id: BabelNodeIdentifier, typeParameters?: ?BabelNodeTypeParameterDeclaration, _extends?: any, body: BabelNodeTSInterfaceBody, declare?: boolean): BabelNodeTSInterfaceDeclaration;
+  declare function tSExpressionWithTypeArguments(expression: BabelNodeTSEntityName, typeParameters?: ?BabelNodeTSTypeParameterInstantiation): BabelNodeTSExpressionWithTypeArguments;
+  declare function tSInterfaceDeclaration(id: BabelNodeIdentifier, typeParameters?: ?BabelNodeTSTypeParameterDeclaration, _extends?: any, body: BabelNodeTSInterfaceBody, declare?: boolean): BabelNodeTSInterfaceDeclaration;
   declare function tSInterfaceBody(body: any): BabelNodeTSInterfaceBody;
-  declare function tSTypeAliasDeclaration(id: BabelNodeIdentifier, typeParameters?: ?BabelNodeTypeParameterDeclaration, typeAnnotation: BabelNodeTSType, declare?: boolean): BabelNodeTSTypeAliasDeclaration;
+  declare function tSTypeAliasDeclaration(id: BabelNodeIdentifier, typeParameters?: ?BabelNodeTSTypeParameterDeclaration, typeAnnotation: BabelNodeTSType, declare?: boolean): BabelNodeTSTypeAliasDeclaration;
   declare function tSAsExpression(expression: BabelNodeExpression, typeAnnotation: BabelNodeTSType): BabelNodeTSAsExpression;
   declare function tSTypeAssertion(typeAnnotation: BabelNodeTSType, expression: BabelNodeExpression): BabelNodeTSTypeAssertion;
   declare function tSEnumDeclaration(id: BabelNodeIdentifier, members: any, _const?: boolean, declare?: boolean, initializer?: ?BabelNodeExpression): BabelNodeTSEnumDeclaration;
@@ -1621,6 +1639,9 @@ declare module "@babel/types" {
   declare function isJSXOpeningElement(node: Object, opts?: ?Object): boolean %checks (node instanceof BabelNodeJSXOpeningElement)
   declare function isJSXSpreadAttribute(node: Object, opts?: ?Object): boolean %checks (node instanceof BabelNodeJSXSpreadAttribute)
   declare function isJSXText(node: Object, opts?: ?Object): boolean %checks (node instanceof BabelNodeJSXText)
+  declare function isJSXFragment(node: Object, opts?: ?Object): boolean %checks (node instanceof BabelNodeJSXFragment)
+  declare function isJSXOpeningFragment(node: Object, opts?: ?Object): boolean %checks (node instanceof BabelNodeJSXOpeningFragment)
+  declare function isJSXClosingFragment(node: Object, opts?: ?Object): boolean %checks (node instanceof BabelNodeJSXClosingFragment)
   declare function isNoop(node: Object, opts?: ?Object): boolean %checks (node instanceof BabelNodeNoop)
   declare function isParenthesizedExpression(node: Object, opts?: ?Object): boolean %checks (node instanceof BabelNodeParenthesizedExpression)
   declare function isAwaitExpression(node: Object, opts?: ?Object): boolean %checks (node instanceof BabelNodeAwaitExpression)
@@ -1727,6 +1748,8 @@ declare module "@babel/types" {
   declare function isTSType(node: Object, opts?: ?Object): boolean
   declare function isNumberLiteral(node: Object, opts?: ?Object): boolean
   declare function isRegexLiteral(node: Object, opts?: ?Object): boolean
+  declare function isRestProperty(node: Object, opts?: ?Object): boolean
+  declare function isSpreadProperty(node: Object, opts?: ?Object): boolean
   declare function validate(n: BabelNode, key: string, value: mixed): void;
   declare function clone<T>(n: T): T;
   declare function cloneDeep<T>(n: T): T;

package.json

@@ -10,17 +10,18 @@
     "test": "make test"
   },
   "devDependencies": {
-    "@babel/cli": "7.0.0-beta.5",
-    "@babel/core": "7.0.0-beta.5",
-    "@babel/preset-env": "7.0.0-beta.5",
-    "@babel/preset-flow": "7.0.0-beta.5",
-    "@babel/preset-stage-0": "7.0.0-beta.5",
-    "@babel/register": "7.0.0-beta.5",
+    "@babel/cli": "7.0.0-beta.33",
+    "@babel/core": "7.0.0-beta.33",
+    "@babel/plugin-proposal-export-namespace-from": "7.0.0-beta.33",
+    "@babel/preset-env": "7.0.0-beta.33",
+    "@babel/preset-flow": "7.0.0-beta.33",
+    "@babel/preset-stage-0": "7.0.0-beta.33",
+    "@babel/register": "7.0.0-beta.33",
     "async": "^1.5.0",
     "babel-eslint": "^8.0.1",
     "babel-loader": "8.0.0-beta.0",
     "babel-plugin-istanbul": "^4.1.4",
-    "babylon": "7.0.0-beta.30",
+    "babylon": "7.0.0-beta.33",
     "browserify": "^13.1.1",
     "bundle-collapser": "^1.2.1",
     "chai": "^4.1.0",
@@ -30,7 +31,7 @@
     "eslint-config-babel": "^7.0.2",
     "eslint-plugin-flowtype": "^2.20.0",
     "eslint-plugin-prettier": "^2.2.0",
-    "flow-bin": "^0.57.3",
+    "flow-bin": "^0.59.0",
     "graceful-fs": "^4.1.11",
     "gulp": "^3.9.0",
     "gulp-babel": "^8.0.0-beta.0",
@@ -50,7 +51,7 @@
     "mocha": "^3.0.0",
     "nyc": "^11.0.3",
     "output-file-sync": "^2.0.0",
-    "prettier": "1.7.3",
+    "prettier": "1.9.1",
     "pump": "^1.0.2",
     "rimraf": "^2.4.3",
     "semver": "^5.0.0",
@@ -72,8 +73,7 @@
       "scripts/*.js",
       "packages/*/test/**",
       "packages/babel-standalone/**",
-      "codemods/*/test/**",
-      "experimental/*/test/**"
+      "codemods/*/test/**"
     ],
     "sourceMap": false,
     "instrument": false

packages/README.md

@@ -45,7 +45,7 @@ Check out the [`babel-handbook`](https://github.com/thejameskyle/babel-handbook/
 | [`@babel/helpers`](/packages/babel-helpers) | [![npm](https://img.shields.io/npm/v/babel-helpers.svg?maxAge=2592000)](https://www.npmjs.com/package/babel-helpers) | [![Dependency Status](https://david-dm.org/babel/babel.svg?path=packages/babel-helpers)](https://david-dm.org/babel/babel?path=packages/babel-helpers) |
 | [`@babel/code-frame`](/packages/babel-code-frame) | [![npm](https://img.shields.io/npm/v/babel-code-frame.svg?maxAge=2592000)](https://www.npmjs.com/package/babel-code-frame) | [![Dependency Status](https://david-dm.org/babel/babel.svg?path=packages/babel-code-frame)](https://david-dm.org/babel/babel?path=packages/babel-code-frame) |
 
-- [`@babel/cli`](/packages/babel-cli) is the CLI tool that runs `@babel/core` and helps with outputting to a directory, a file, stdout and more (also includes `babel-node`). Check out the [docs](https://babeljs.io/docs/usage/cli/).
+- [`@babel/cli`](/packages/babel-cli) is the CLI tool that runs `@babel/core` and helps with outputting to a directory, a file, stdout and more (also includes `@babel/node` cli). Check out the [docs](https://babeljs.io/docs/usage/cli/).
 - [`@babel/types`](/packages/babel-types) is used to validate, build and change AST nodes.
 - [`@babel/polyfill`](/packages/babel-polyfill) is [literally a wrapper](https://github.com/babel/babel/blob/master/packages/babel-polyfill/src/index.js) around [`core-js`](https://github.com/zloirock/core-js) and [regenerator-runtime](https://github.com/facebook/regenerator/tree/master/packages/regenerator-runtime). Check out the [docs](https://babeljs.io/docs/usage/polyfill/).
 - [`@babel/runtime`](/packages/babel-runtime) is similar to the polyfill except that it doesn't modify the global scope and is to be used with [`@babel/plugin-transform-runtime`](/packages/babel-plugin-transform-runtime) (usually in library/plugin code). Check out the [docs](https://babeljs.io/docs/plugins/transform-runtime/).

packages/babel-cli/README.md

@@ -4,7 +4,7 @@
 
 In addition, various entry point scripts live in the top-level package at `@babel/cli/bin`.
 
-There are some shell-executable utility scripts, `babel-external-helpers.js` and `babel-node.js`, and the main Babel cli script, `babel.js`.
+There is a shell-executable utility script, `babel-external-helpers.js`, and the main Babel cli script, `babel.js`.
 
 ## Install
 

packages/babel-cli/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/cli",
-  "version": "7.0.0-beta.32",
+  "version": "7.0.0-beta.36",
   "description": "Babel command line.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -29,11 +29,11 @@
     "chokidar": "^1.6.1"
   },
   "peerDependencies": {
-    "@babel/core": "7.0.0-beta.32"
+    "@babel/core": "7.0.0-beta.36"
   },
   "devDependencies": {
-    "@babel/core": "7.0.0-beta.32",
-    "@babel/helper-fixtures": "7.0.0-beta.32"
+    "@babel/core": "7.0.0-beta.36",
+    "@babel/helper-fixtures": "7.0.0-beta.36"
   },
   "bin": {
     "babel": "./bin/babel.js",

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

@@ -49,6 +49,11 @@ commander.option(
   collect,
 );
 commander.option("--config-file [path]", "Path a to .babelrc file to use");
+commander.option(
+  "--env-name [name]",
+  "The name of the 'env' to use when loading configs and plugins. " +
+    "Defaults to the value of BABEL_ENV, or else NODE_ENV, or else 'development'.",
+);
 
 // Basic file input configuration.
 commander.option("--source-type [script|module]", "");

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

@@ -1 +1 @@
-SyntaxError: test.js: Unexpected token, expected ; (2:10)
+SyntaxError: test.js: Unexpected token, expected ";" (2:10)

packages/babel-code-frame/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/code-frame",
-  "version": "7.0.0-beta.32",
+  "version": "7.0.0-beta.36",
   "description": "Generate errors that contain a code frame that point to source locations.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",

packages/babel-core/README.md

@@ -144,10 +144,11 @@ Following is a table of the options you can use:
 | `auxiliaryCommentAfter`  | `null`               | Attach a comment after all non-user injected code |
 | `auxiliaryCommentBefore` | `null`               | Attach a comment before all non-user injected code |
 | `babelrc`                | `true`               | Specify whether or not to use .babelrc and .babelignore files. Not available when using the CLI, [use `--no-babelrc` instead](https://babeljs.io/docs/usage/cli/#babel-ignoring-babelrc) |
+| `envName`                | env vars             | Defaults to environment variable `BABEL_ENV` if set, or else `NODE_ENV` if set, or else it defaults to `"development"` |
 | `code`                   | `true`               | Enable code generation |
 | `comments`               | `true`               | Output comments in generated output |
 | `compact`                | `"auto"`             | Do not include superfluous whitespace characters and line terminators. When set to `"auto"` compact is set to `true` on input sizes of >500KB |
-| `env`                    | `{}`                 | This is an object of keys that represent different environments. For example, you may have: `{ env: { production: { /* specific options */ } } }` which will use those options when the environment variable `BABEL_ENV` is set to `"production"`. If `BABEL_ENV` isn't set then `NODE_ENV` will be used, if it's not set then it defaults to `"development"` |
+| `env`                    | `{}`                 | This is an object of keys that represent different environments. For example, you may have: `{ env: { production: { /* specific options */ } } }` which will use those options when the `envName` is `production` |
 | `extends`                | `null`               | A path to a `.babelrc` file to extend |
 | `filename`               | `"unknown"`          | Filename for use in errors etc |
 | `filenameRelative`       | `(filename)`         | Filename relative to `sourceRoot` |

packages/babel-core/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@babel/core",
-  "version": "7.0.0-beta.32",
+  "version": "7.0.0-beta.36",
   "description": "Babel compiler core.",
   "main": "./lib/index.js",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
@@ -23,18 +23,18 @@
     "compiler"
   ],
   "browser": {
-    "./lib/config/loading/files/index.js": "./lib/config/loading/files/index-browser.js",
+    "./lib/config/files/index.js": "./lib/config/files/index-browser.js",
     "./lib/transform-file.js": "./lib/transform-file-browser.js",
     "./lib/transform-file-sync.js": "./lib/transform-file-sync-browser.js"
   },
   "dependencies": {
-    "@babel/code-frame": "7.0.0-beta.32",
-    "@babel/generator": "7.0.0-beta.32",
-    "@babel/helpers": "7.0.0-beta.32",
-    "@babel/template": "7.0.0-beta.32",
-    "@babel/traverse": "7.0.0-beta.32",
-    "@babel/types": "7.0.0-beta.32",
-    "babylon": "7.0.0-beta.32",
+    "@babel/code-frame": "7.0.0-beta.36",
+    "@babel/generator": "7.0.0-beta.36",
+    "@babel/helpers": "7.0.0-beta.36",
+    "@babel/template": "7.0.0-beta.36",
+    "@babel/traverse": "7.0.0-beta.36",
+    "@babel/types": "7.0.0-beta.36",
+    "babylon": "7.0.0-beta.36",
     "convert-source-map": "^1.1.0",
     "debug": "^3.0.1",
     "json5": "^0.5.0",
@@ -44,7 +44,7 @@
     "source-map": "^0.5.0"
   },
   "devDependencies": {
-    "@babel/helper-transform-fixture-test-runner": "7.0.0-beta.32",
-    "@babel/register": "7.0.0-beta.32"
+    "@babel/helper-transform-fixture-test-runner": "7.0.0-beta.36",
+    "@babel/register": "7.0.0-beta.36"
   }
 }

packages/babel-core/src/config/build-config-chain.js

@@ -1,419 +0,0 @@
-// @flow
-
-import { getEnv } from "./helpers/environment";
-import path from "path";
-import micromatch from "micromatch";
-import buildDebug from "debug";
-import {
-  validate,
-  type ValidatedOptions,
-  type PluginList,
-  type IgnoreList,
-} from "./options";
-
-const debug = buildDebug("babel:config:config-chain");
-
-import { findConfigs, loadConfig, type ConfigFile } from "./loading/files";
-
-import { makeWeakCache, makeStrongCache } from "./caching";
-
-export type ConfigItem = {
-  type: "arguments" | "env" | "file",
-  options: ValidatedOptions,
-  alias: string,
-  dirname: string,
-};
-
-type ConfigPart =
-  | {
-      part: "config",
-      config: ConfigItem,
-      ignore: ?IgnoreList,
-      only: ?IgnoreList,
-      activeEnv: string | null,
-    }
-  | {
-      part: "extends",
-      path: string,
-      dirname: string,
-      activeEnv: string | null,
-    };
-
-export default function buildConfigChain(
-  opts: ValidatedOptions,
-): Array<ConfigItem> | null {
-  const filename = opts.filename ? path.resolve(opts.filename) : null;
-  const builder = new ConfigChainBuilder(
-    filename ? new LoadedFile(filename) : null,
-  );
-
-  const envKey = getEnv();
-  try {
-    builder.mergeConfigArguments(opts, process.cwd(), envKey);
-
-    // resolve all .babelrc files
-    if (opts.babelrc !== false && filename) {
-      findConfigs(path.dirname(filename)).forEach(configFile =>
-        builder.mergeConfigFile(configFile, envKey),
-      );
-    }
-  } catch (e) {
-    if (e.code !== "BABEL_IGNORED_FILE") throw e;
-
-    return null;
-  }
-
-  return builder.configs.reverse();
-}
-
-class ConfigChainBuilder {
-  file: LoadedFile | null;
-  configs: Array<ConfigItem> = [];
-  seenFiles: Set<ConfigFile> = new Set();
-
-  constructor(file: LoadedFile | null) {
-    this.file = file;
-  }
-
-  mergeConfigArguments(
-    opts: ValidatedOptions,
-    dirname: string,
-    envKey: string,
-  ) {
-    flattenArgumentsOptionsParts(opts, dirname, envKey).forEach(part =>
-      this._processConfigPart(part, envKey),
-    );
-  }
-
-  mergeConfigFile(file: ConfigFile, envKey: string) {
-    if (this.seenFiles.has(file)) {
-      throw new Error(
-        `Cycle detected in Babel configuration file through "${file.filepath}".`,
-      );
-    }
-
-    const parts = flattenFileOptionsParts(file)(envKey);
-
-    this.seenFiles.add(file);
-    parts.forEach(part => this._processConfigPart(part, envKey));
-    this.seenFiles.delete(file);
-  }
-
-  _processConfigPart(part: ConfigPart, envKey: string) {
-    if (part.part === "config") {
-      const { ignore, only } = part;
-
-      // Bail out ASAP if this file is ignored so that we run as little logic as possible on ignored files.
-      if (
-        this.file &&
-        this.file.shouldIgnore(ignore, only, part.config.dirname)
-      ) {
-        // TODO(logan): This is a really gross way to bail out. Avoid this in rewrite.
-        throw Object.assign((new Error("This file has been ignored."): any), {
-          code: "BABEL_IGNORED_FILE",
-        });
-      }
-
-      this.configs.push(part.config);
-    } else {
-      this.mergeConfigFile(loadConfig(part.path, part.dirname), envKey);
-    }
-  }
-}
-
-/**
- * Given the root config object passed to Babel, split it into the separate
- * config parts. The resulting config objects in the 'ConfigPart' have their
- * object identity preserved between calls so that they can be used for caching.
- */
-function flattenArgumentsOptionsParts(
-  opts: ValidatedOptions,
-  dirname: string,
-  envKey: string,
-): Array<ConfigPart> {
-  const {
-    env,
-    plugins,
-    presets,
-    passPerPreset,
-    extends: extendsPath,
-    ...options
-  } = opts;
-
-  const raw = [];
-  if (env) {
-    raw.push(...flattenArgumentsEnvOptionsParts(env)(dirname)(envKey));
-  }
-
-  if (Object.keys(options).length > 0) {
-    raw.push(...flattenOptionsParts(buildArgumentsItem(options, dirname)));
-  }
-
-  if (plugins) {
-    raw.push(...flattenArgumentsPluginsOptionsParts(plugins)(dirname));
-  }
-  if (presets) {
-    raw.push(
-      ...flattenArgumentsPresetsOptionsParts(presets)(!!passPerPreset)(dirname),
-    );
-  }
-
-  if (extendsPath != null) {
-    raw.push(
-      ...flattenOptionsParts(
-        buildArgumentsItem({ extends: extendsPath }, dirname),
-      ),
-    );
-  }
-
-  return raw;
-}
-
-/**
- * For the top-level 'options' object, we cache the env list based on
- * the object identity of the 'env' object.
- */
-const flattenArgumentsEnvOptionsParts = makeWeakCache((env: {}) => {
-  const options: ValidatedOptions = { env };
-
-  return makeStrongCache((dirname: string) =>
-    flattenOptionsPartsLookup(buildArgumentsItem(options, dirname)),
-  );
-});
-
-/**
- * For the top-level 'options' object, we cache the plugin list based on
- * the object identity of the 'plugins' object.
- */
-const flattenArgumentsPluginsOptionsParts = makeWeakCache(
-  (plugins: PluginList) => {
-    const options: ValidatedOptions = { plugins };
-
-    return makeStrongCache((dirname: string) =>
-      flattenOptionsParts(buildArgumentsItem(options, dirname)),
-    );
-  },
-);
-
-/**
- * For the top-level 'options' object, we cache the preset list based on
- * the object identity of the 'presets' object.
- */
-const flattenArgumentsPresetsOptionsParts = makeWeakCache(
-  (presets: PluginList) =>
-    makeStrongCache((passPerPreset: boolean) => {
-      // The concept of passPerPreset is integrally tied to the preset list
-      // so unfortunately we need to copy both values here, adding an extra
-      // layer of caching functions.
-      const options = { presets, passPerPreset };
-
-      return makeStrongCache((dirname: string) =>
-        flattenOptionsParts(buildArgumentsItem(options, dirname)),
-      );
-    }),
-);
-
-function buildArgumentsItem(
-  options: ValidatedOptions,
-  dirname: string,
-): ConfigItem {
-  return {
-    type: "arguments",
-    options,
-    alias: "base",
-    dirname,
-  };
-}
-
-/**
- * Given a config from a specific file, return a list of ConfigPart objects
- * with object identity preserved for all 'config' part objects for use
- * with caching later in config processing.
- */
-const flattenFileOptionsParts = makeWeakCache((file: ConfigFile) => {
-  return flattenOptionsPartsLookup({
-    type: "file",
-    options: validate("file", file.options),
-    alias: file.filepath,
-    dirname: file.dirname,
-  });
-});
-
-/**
- * Given a config, create a function that will return the config parts for
- * the environment passed as the first argument.
- */
-function flattenOptionsPartsLookup(
-  config: ConfigItem,
-): (string | null) => Array<ConfigPart> {
-  const parts = flattenOptionsParts(config);
-
-  const def = parts.filter(part => part.activeEnv === null);
-  const lookup = new Map();
-
-  parts.forEach(part => {
-    if (part.activeEnv !== null) lookup.set(part.activeEnv, []);
-  });
-
-  for (const [activeEnv, values] of lookup) {
-    parts.forEach(part => {
-      if (part.activeEnv === null || part.activeEnv === activeEnv) {
-        values.push(part);
-      }
-    });
-  }
-
-  return envKey => lookup.get(envKey) || def;
-}
-
-/**
- * Given a generic config object, flatten it into its various parts so that
- * then can be cached and processed later.
- */
-function flattenOptionsParts(
-  config: ConfigItem,
-  activeEnv: string | null = null,
-): Array<ConfigPart> {
-  const { options: rawOpts, alias, dirname } = config;
-
-  const parts = [];
-
-  if (rawOpts.env) {
-    for (const envKey of Object.keys(rawOpts.env)) {
-      if (rawOpts.env[envKey]) {
-        parts.push(
-          ...flattenOptionsParts(
-            {
-              type: "env",
-              options: rawOpts.env[envKey],
-              alias: alias + `.env.${envKey}`,
-              dirname,
-            },
-            envKey,
-          ),
-        );
-      }
-    }
-  }
-
-  parts.push({
-    part: "config",
-    config,
-    ignore: rawOpts.ignore,
-    only: rawOpts.only,
-    activeEnv,
-  });
-
-  if (rawOpts.extends != null) {
-    parts.push({
-      part: "extends",
-      path: rawOpts.extends,
-      dirname,
-      activeEnv,
-    });
-  }
-
-  return parts;
-}
-
-/**
- * Track a given file and expose function to check if it should be ignored.
- */
-class LoadedFile {
-  filename: string;
-  possibleDirs: null | Array<string> = null;
-
-  constructor(filename) {
-    this.filename = filename;
-  }
-
-  /**
-   * Tests if a filename should be ignored based on "ignore" and "only" options.
-   */
-  shouldIgnore(
-    ignore: ?IgnoreList,
-    only: ?IgnoreList,
-    dirname: string,
-  ): boolean {
-    if (ignore) {
-      if (this._matchesPatterns(ignore, dirname)) {
-        debug(
-          "Ignored %o because it matched one of %O from %o",
-          this.filename,
-          ignore,
-          dirname,
-        );
-        return true;
-      }
-    }
-
-    if (only) {
-      if (!this._matchesPatterns(only, dirname)) {
-        debug(
-          "Ignored %o because it failed to match one of %O from %o",
-          this.filename,
-          only,
-          dirname,
-        );
-        return true;
-      }
-    }
-
-    return false;
-  }
-
-  /**
-   * Returns result of calling function with filename if pattern is a function.
-   * Otherwise returns result of matching pattern Regex with filename.
-   */
-  _matchesPatterns(patterns: IgnoreList, dirname: string): boolean {
-    const res = [];
-    const strings = [];
-    const fns = [];
-
-    patterns.forEach(pattern => {
-      if (typeof pattern === "string") strings.push(pattern);
-      else if (typeof pattern === "function") fns.push(pattern);
-      else res.push(pattern);
-    });
-
-    const filename = this.filename;
-    if (res.some(re => re.test(filename))) return true;
-    if (fns.some(fn => fn(filename))) return true;
-
-    if (strings.length > 0) {
-      let possibleDirs = this.possibleDirs;
-      // Lazy-init so we don't initialize this for files that have no glob patterns.
-      if (!possibleDirs) {
-        possibleDirs = this.possibleDirs = [];
-
-        possibleDirs.push(filename);
-
-        let current = filename;
-        while (true) {
-          const previous = current;
-          current = path.dirname(current);
-          if (previous === current) break;
-
-          possibleDirs.push(current);
-        }
-      }
-
-      const absolutePatterns = strings.map(pattern => {
-        // Preserve the "!" prefix so that micromatch can use it for negation.
-        const negate = pattern[0] === "!";
-        if (negate) pattern = pattern.slice(1);
-
-        return (negate ? "!" : "") + path.resolve(dirname, pattern);
-      });
-
-      if (
-        micromatch(possibleDirs, absolutePatterns, { nocase: true }).length > 0
-      ) {
-        return true;
-      }
-    }
-
-    return false;
-  }
-}

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

@@ -1,29 +1,34 @@
 // @flow
 
-type CacheConfigurator = CacheConfiguratorFn & CacheConfiguratorObj;
+type SimpleCacheConfigurator = SimpleCacheConfiguratorFn &
+  SimpleCacheConfiguratorObj;
 
-type CacheConfiguratorFn = {
+type SimpleCacheConfiguratorFn = {
   (boolean): void,
   <T>(handler: () => T): T,
 };
-type CacheConfiguratorObj = {
+type SimpleCacheConfiguratorObj = {
   forever: () => void,
   never: () => void,
   using: <T>(handler: () => T) => T,
   invalidate: <T>(handler: () => T) => T,
 };
 
-type CacheEntry<ResultT> = Array<[ResultT, () => boolean]>;
+type CacheEntry<ResultT, SideChannel> = Array<{
+  value: ResultT,
+  valid: SideChannel => boolean,
+}>;
+
+export type { CacheConfigurator };
 
 /**
  * Given a function with a single argument, cache its results based on its argument and how it
  * configures its caching behavior. Cached values are stored strongly.
  */
-export function makeStrongCache<ArgT, ResultT>(
-  handler: (ArgT, CacheConfigurator) => ResultT,
-  autoPermacache?: boolean,
-): ArgT => ResultT {
-  return makeCachedFunction(new Map(), handler, autoPermacache);
+export function makeStrongCache<ArgT, ResultT, SideChannel>(
+  handler: (ArgT, CacheConfigurator<SideChannel>) => ResultT,
+): (ArgT, SideChannel) => ResultT {
+  return makeCachedFunction(new Map(), handler);
 }
 
 /**
@@ -31,190 +36,182 @@ export function makeStrongCache<ArgT, ResultT>(
  * configures its caching behavior. Cached values are stored weakly and the function argument must be
  * an object type.
  */
-export function makeWeakCache<ArgT: {} | Array<*> | $ReadOnlyArray<*>, ResultT>(
-  handler: (ArgT, CacheConfigurator) => ResultT,
-  autoPermacache?: boolean,
-): ArgT => ResultT {
-  return makeCachedFunction(new WeakMap(), handler, autoPermacache);
+export function makeWeakCache<
+  ArgT: {} | Array<*> | $ReadOnlyArray<*>,
+  ResultT,
+  SideChannel,
+>(
+  handler: (ArgT, CacheConfigurator<SideChannel>) => ResultT,
+): (ArgT, SideChannel) => ResultT {
+  return makeCachedFunction(new WeakMap(), handler);
 }
 
-type CacheMap<ArgT, ResultT> =
-  | Map<ArgT, CacheEntry<ResultT>>
-  | WeakMap<ArgT, CacheEntry<ResultT>>;
+type CacheMap<ArgT, ResultT, SideChannel> =
+  | Map<ArgT, CacheEntry<ResultT, SideChannel>>
+  | WeakMap<ArgT, CacheEntry<ResultT, SideChannel>>;
 
-function makeCachedFunction<ArgT, ResultT, Cache: CacheMap<ArgT, ResultT>>(
+function makeCachedFunction<
+  ArgT,
+  ResultT,
+  SideChannel,
+  Cache: CacheMap<ArgT, ResultT, SideChannel>,
+>(
   callCache: Cache,
-  handler: (ArgT, CacheConfigurator) => ResultT,
-  autoPermacache: boolean = true,
-): ArgT => ResultT {
-  return function cachedFunction(arg) {
-    let cachedValue: CacheEntry<ResultT> | void = callCache.get(arg);
+  handler: (ArgT, CacheConfigurator<SideChannel>) => ResultT,
+): (ArgT, SideChannel) => ResultT {
+  return function cachedFunction(arg, data) {
+    let cachedValue: CacheEntry<ResultT, SideChannel> | void = callCache.get(
+      arg,
+    );
 
     if (cachedValue) {
-      for (const [value, valid] of cachedValue) {
-        if (valid()) return value;
+      for (const { value, valid } of cachedValue) {
+        if (valid(data)) return value;
       }
     }
 
-    const { cache, result, deactivate } = makeCacheConfig();
+    const cache = new CacheConfigurator(data);
 
     const value = handler(arg, cache);
 
-    if (autoPermacache && !result.configured) cache.forever();
+    if (!cache.configured()) cache.forever();
 
-    deactivate();
+    cache.deactivate();
 
-    if (!result.configured) {
-      // eslint-disable-next-line max-len
-      throw new Error(
-        [
-          "Caching was left unconfigured. Babel's plugins, presets, and .babelrc.js files can be configured",
-          "for various types of caching, using the first param of their handler functions:",
-          "",
-          "module.exports = function(api) {",
-          "  // The API exposes the following:",
-          "",
-          "  // Cache the returned value forever and don't call this function again.",
-          "  api.cache(true);",
-          "",
-          "  // Don't cache at all. Not recommended because it will be very slow.",
-          "  api.cache(false);",
-          "",
-          "  // Cached based on the value of some function. If this function returns a value different from",
-          "  // a previously-encountered value, the plugins will re-evaluate.",
-          "  var env = api.cache(() => process.env.NODE_ENV);",
-          "",
-          "  // If testing for a specific env, we recommend specifics to avoid instantiating a plugin for",
-          "  // any possible NODE_ENV value that might come up during plugin execution.",
-          '  var isProd = api.cache(() => process.env.NODE_ENV === "production");',
-          "",
-          "  // .cache(fn) will perform a linear search though instances to find the matching plugin based",
-          "  // based on previous instantiated plugins. If you want to recreate the plugin and discard the",
-          "  // previous instance whenever something changes, you may use:",
-          '  var isProd = api.cache.invalidate(() => process.env.NODE_ENV === "production");',
-          "",
-          "  // Note, we also expose the following more-verbose versions of the above examples:",
-          "  api.cache.forever(); // api.cache(true)",
-          "  api.cache.never();   // api.cache(false)",
-          "  api.cache.using(fn); // api.cache(fn)",
-          "",
-          "  // Return the value that will be cached.",
-          "  return { };",
-          "};",
-        ].join("\n"),
-      );
-    }
-
-    if (!result.never) {
-      if (result.forever) {
-        cachedValue = [[value, () => true]];
-      } else if (result.invalidate) {
-        cachedValue = [[value, result.valid]];
-      } else {
-        cachedValue = cachedValue || [];
-        cachedValue.push([value, result.valid]);
-      }
-      callCache.set(arg, cachedValue);
+    switch (cache.mode()) {
+      case "forever":
+        cachedValue = [{ value, valid: () => true }];
+        callCache.set(arg, cachedValue);
+        break;
+      case "invalidate":
+        cachedValue = [{ value, valid: cache.validator() }];
+        callCache.set(arg, cachedValue);
+        break;
+      case "valid":
+        if (cachedValue) {
+          cachedValue.push({ value, valid: cache.validator() });
+        } else {
+          cachedValue = [{ value, valid: cache.validator() }];
+          callCache.set(arg, cachedValue);
+        }
     }
 
     return value;
   };
 }
 
-function makeCacheConfig(): {
-  cache: CacheConfigurator,
-  result: *,
-  deactivate: () => void,
-} {
-  const pairs = [];
+class CacheConfigurator<SideChannel = void> {
+  _active: boolean = true;
+  _never: boolean = false;
+  _forever: boolean = false;
+  _invalidate: boolean = false;
 
-  const result = {
-    configured: false,
-    never: false,
-    forever: false,
-    invalidate: false,
-    valid: () => pairs.every(([key, fn]) => key === fn()),
-  };
+  _configured: boolean = false;
 
-  let active = true;
-  const deactivate = () => {
-    active = false;
-  };
+  _pairs: Array<[mixed, (SideChannel) => mixed]> = [];
 
-  const cache: CacheConfigurator = Object.assign(
-    (function cacheFn(val) {
-      if (typeof val === "boolean") {
-        if (val) cache.forever();
-        else cache.never();
-        return;
-      }
+  _data: SideChannel;
 
-      return cache.using(val);
-    }: any),
-    ({
-      forever() {
-        if (!active) {
-          throw new Error(
-            "Cannot change caching after evaluation has completed.",
-          );
-        }
-        if (result.never) {
-          throw new Error("Caching has already been configured with .never()");
-        }
-        result.forever = true;
-        result.configured = true;
-      },
-      never() {
-        if (!active) {
-          throw new Error(
-            "Cannot change caching after evaluation has completed.",
-          );
-        }
-        if (result.forever) {
-          throw new Error(
-            "Caching has already been configured with .forever()",
-          );
-        }
-        result.never = true;
-        result.configured = true;
-      },
-      using<T>(handler: () => T): T {
-        if (!active) {
-          throw new Error(
-            "Cannot change caching after evaluation has completed.",
-          );
-        }
-        if (result.never || result.forever) {
-          throw new Error(
-            "Caching has already been configured with .never or .forever()",
-          );
-        }
-        result.configured = true;
+  constructor(data: SideChannel) {
+    this._data = data;
+  }
 
-        const key = handler();
-        pairs.push([key, handler]);
-        return key;
-      },
-      invalidate<T>(handler: () => T): T {
-        if (!active) {
-          throw new Error(
-            "Cannot change caching after evaluation has completed.",
-          );
-        }
-        if (result.never || result.forever) {
-          throw new Error(
-            "Caching has already been configured with .never or .forever()",
-          );
-        }
-        result.invalidate = true;
-        result.configured = true;
+  simple() {
+    return makeSimpleConfigurator(this);
+  }
 
-        const key = handler();
-        pairs.push([key, handler]);
-        return key;
-      },
-    }: CacheConfiguratorObj),
-  );
+  mode() {
+    if (this._never) return "never";
+    if (this._forever) return "forever";
+    if (this._invalidate) return "invalidate";
+    return "valid";
+  }
 
-  return { cache, result, deactivate };
+  forever() {
+    if (!this._active) {
+      throw new Error("Cannot change caching after evaluation has completed.");
+    }
+    if (this._never) {
+      throw new Error("Caching has already been configured with .never()");
+    }
+    this._forever = true;
+    this._configured = true;
+  }
+
+  never() {
+    if (!this._active) {
+      throw new Error("Cannot change caching after evaluation has completed.");
+    }
+    if (this._forever) {
+      throw new Error("Caching has already been configured with .forever()");
+    }
+    this._never = true;
+    this._configured = true;
+  }
+
+  using<T>(handler: SideChannel => T): T {
+    if (!this._active) {
+      throw new Error("Cannot change caching after evaluation has completed.");
+    }
+    if (this._never || this._forever) {
+      throw new Error(
+        "Caching has already been configured with .never or .forever()",
+      );
+    }
+    this._configured = true;
+
+    const key = handler(this._data);
+    this._pairs.push([key, handler]);
+    return key;
+  }
+
+  invalidate<T>(handler: SideChannel => T): T {
+    if (!this._active) {
+      throw new Error("Cannot change caching after evaluation has completed.");
+    }
+    if (this._never || this._forever) {
+      throw new Error(
+        "Caching has already been configured with .never or .forever()",
+      );
+    }
+    this._invalidate = true;
+    this._configured = true;
+
+    const key = handler(this._data);
+    this._pairs.push([key, handler]);
+    return key;
+  }
+
+  validator(): SideChannel => boolean {
+    const pairs = this._pairs;
+    return (data: SideChannel) => pairs.every(([key, fn]) => key === fn(data));
+  }
+
+  deactivate() {
+    this._active = false;
+  }
+
+  configured() {
+    return this._configured;
+  }
+}
+
+function makeSimpleConfigurator(
+  cache: CacheConfigurator<any>,
+): SimpleCacheConfigurator {
+  function cacheFn(val) {
+    if (typeof val === "boolean") {
+      if (val) cache.forever();
+      else cache.never();
+      return;
+    }
+
+    return cache.using(val);
+  }
+  cacheFn.forever = () => cache.forever();
+  cacheFn.never = () => cache.never();
+  cacheFn.using = cb => cache.using(() => cb());
+  cacheFn.invalidate = cb => cache.invalidate(() => cb());
+
+  return (cacheFn: any);
 }

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

@@ -0,0 +1,452 @@
+// @flow
+
+import path from "path";
+import micromatch from "micromatch";
+import buildDebug from "debug";
+import {
+  validate,
+  type ValidatedOptions,
+  type IgnoreList,
+} from "./validation/options";
+
+const debug = buildDebug("babel:config:config-chain");
+
+import {
+  findBabelrc,
+  findBabelignore,
+  loadConfig,
+  type ConfigFile,
+} from "./files";
+
+import { makeWeakCache, makeStrongCache } from "./caching";
+
+import {
+  createCachedDescriptors,
+  createUncachedDescriptors,
+  type UnloadedDescriptor,
+  type OptionsAndDescriptors,
+  type ValidatedFile,
+} from "./config-descriptors";
+
+export type ConfigChain = {
+  plugins: Array<UnloadedDescriptor>,
+  presets: Array<UnloadedDescriptor>,
+  options: Array<ValidatedOptions>,
+};
+
+export type PresetInstance = {
+  options: ValidatedOptions,
+  alias: string,
+  dirname: string,
+};
+
+type ConfigContext = {
+  filename: string | null,
+  cwd: string,
+  envName: string,
+};
+
+type ConfigContextNamed = {
+  ...ConfigContext,
+  filename: string,
+};
+
+/**
+ * Build a config chain for a given preset.
+ */
+export const buildPresetChain = makeWeakCache(
+  ({ dirname, options, alias }: PresetInstance): ConfigChain => {
+    const result = createUncachedDescriptors(dirname, options, alias);
+    const { plugins, presets } = result;
+    return {
+      plugins: plugins(),
+      presets: presets(),
+      options: [normalizeOptions(result.options)],
+    };
+  },
+);
+
+/**
+ * Build a config chain for Babel's full root configuration.
+ */
+export function buildRootChain(
+  cwd: string,
+  opts: ValidatedOptions,
+  envName: string,
+): ConfigChain | null {
+  const context = {
+    filename: opts.filename ? path.resolve(cwd, opts.filename) : null,
+    cwd,
+    envName,
+  };
+
+  const programmaticChain = loadProgrammaticChain(
+    {
+      options: opts,
+      dirname: context.cwd,
+    },
+    context,
+  );
+  if (!programmaticChain) return null;
+
+  const fileChain = emptyChain();
+  // resolve all .babelrc files
+  if (opts.babelrc !== false && context.filename !== null) {
+    const filename = context.filename;
+    const babelrcFile = findBabelrc(filename, context.envName);
+    if (babelrcFile) {
+      const result = loadFileChain(babelrcFile, context);
+      if (!result) return null;
+
+      mergeChain(fileChain, result);
+    }
+
+    const babelignoreFile = findBabelignore(filename);
+    if (
+      babelignoreFile &&
+      shouldIgnore(
+        context,
+        babelignoreFile.ignore,
+        null,
+        babelignoreFile.dirname,
+      )
+    ) {
+      return null;
+    }
+  }
+
+  // Insert file chain in front so programmatic options have priority
+  // over configuration file chain items.
+  const chain = mergeChain(
+    mergeChain(emptyChain(), fileChain),
+    programmaticChain,
+  );
+
+  return {
+    plugins: dedupDescriptors(chain.plugins),
+    presets: dedupDescriptors(chain.presets),
+    options: chain.options.map(o => normalizeOptions(o)),
+  };
+}
+
+/**
+ * Build a config chain for just the programmatic options passed into Babel.
+ */
+const loadProgrammaticChain = makeChainWalker({
+  init: arg => arg,
+  root: input => buildRootDescriptors(input, "base", createCachedDescriptors),
+  env: (input, envName) =>
+    buildEnvDescriptors(input, "base", createCachedDescriptors, envName),
+});
+
+/**
+ * Build a config chain for a given file.
+ */
+const loadFileChain = makeChainWalker({
+  init: input => validateFile(input),
+  root: file => loadFileDescriptors(file),
+  env: (file, envName) => loadFileEnvDescriptors(file)(envName),
+});
+const validateFile = makeWeakCache((file: ConfigFile): ValidatedFile => ({
+  filepath: file.filepath,
+  dirname: file.dirname,
+  options: validate("file", file.options),
+}));
+const loadFileDescriptors = makeWeakCache((file: ValidatedFile) =>
+  buildRootDescriptors(file, file.filepath, createUncachedDescriptors),
+);
+const loadFileEnvDescriptors = makeWeakCache((file: ValidatedFile) =>
+  makeStrongCache((envName: string) =>
+    buildEnvDescriptors(
+      file,
+      file.filepath,
+      createUncachedDescriptors,
+      envName,
+    ),
+  ),
+);
+
+function buildRootDescriptors({ dirname, options }, alias, descriptors) {
+  return descriptors(dirname, options, alias);
+}
+
+function buildEnvDescriptors(
+  { dirname, options },
+  alias,
+  descriptors,
+  envName,
+) {
+  const opts = options.env && options.env[envName];
+  return opts ? descriptors(dirname, opts, `${alias}.env["${envName}"]`) : null;
+}
+
+function makeChainWalker<
+  ArgT,
+  InnerT: { options: ValidatedOptions, dirname: string },
+>({
+  init,
+  root,
+  env,
+}: {
+  init: ArgT => InnerT,
+  root: InnerT => OptionsAndDescriptors,
+  env: (InnerT, string) => OptionsAndDescriptors | null,
+}): (ArgT, ConfigContext, Set<ConfigFile> | void) => ConfigChain | null {
+  return (arg, context, files = new Set()) => {
+    const input = init(arg);
+
+    const { dirname } = input;
+
+    const flattenedConfigs = [];
+
+    const rootOpts = root(input);
+    flattenedConfigs.push(rootOpts);
+
+    const envOpts = env(input, context.envName);
+    if (envOpts) {
+      flattenedConfigs.push(envOpts);
+    }
+
+    // Process 'ignore' and 'only' before 'extends' items are processed so
+    // that we don't do extra work loading extended configs if a file is
+    // ignored.
+    if (
+      flattenedConfigs.some(({ options: { ignore, only } }) =>
+        shouldIgnore(context, ignore, only, dirname),
+      )
+    ) {
+      return null;
+    }
+
+    const chain = emptyChain();
+
+    for (const op of flattenedConfigs) {
+      if (!mergeExtendsChain(chain, op.options, dirname, context, files)) {
+        return null;
+      }
+
+      mergeChainOpts(chain, op);
+    }
+    return chain;
+  };
+}
+
+function mergeExtendsChain(
+  chain: ConfigChain,
+  opts: ValidatedOptions,
+  dirname: string,
+  context: ConfigContext,
+  files: Set<ConfigFile>,
+): boolean {
+  if (opts.extends === undefined) return true;
+
+  const file = loadConfig(opts.extends, dirname, context.envName);
+
+  if (files.has(file)) {
+    throw new Error(
+      `Configuration cycle detected loading ${file.filepath}.\n` +
+        `File already loaded following the config chain:\n` +
+        Array.from(files, file => ` - ${file.filepath}`).join("\n"),
+    );
+  }
+
+  files.add(file);
+  const fileChain = loadFileChain(file, context, files);
+  files.delete(file);
+
+  if (!fileChain) return false;
+
+  mergeChain(chain, fileChain);
+
+  return true;
+}
+
+function mergeChain(target: ConfigChain, source: ConfigChain): ConfigChain {
+  target.options.push(...source.options);
+  target.plugins.push(...source.plugins);
+  target.presets.push(...source.presets);
+
+  return target;
+}
+
+function mergeChainOpts(
+  target: ConfigChain,
+  { options, plugins, presets }: OptionsAndDescriptors,
+): ConfigChain {
+  target.options.push(options);
+  target.plugins.push(...plugins());
+  target.presets.push(...presets());
+
+  return target;
+}
+
+function emptyChain(): ConfigChain {
+  return {
+    options: [],
+    presets: [],
+    plugins: [],
+  };
+}
+
+function normalizeOptions(opts: ValidatedOptions): ValidatedOptions {
+  const options = Object.assign({}, opts);
+  delete options.extends;
+  delete options.env;
+  delete options.plugins;
+  delete options.presets;
+  delete options.passPerPreset;
+  delete options.ignore;
+  delete options.only;
+
+  // "sourceMap" is just aliased to sourceMap, so copy it over as
+  // we merge the options together.
+  if (options.sourceMap) {
+    options.sourceMaps = options.sourceMap;
+    delete options.sourceMap;
+  }
+  return options;
+}
+
+function dedupDescriptors(
+  items: Array<UnloadedDescriptor>,
+): Array<UnloadedDescriptor> {
+  const map: Map<
+    Function,
+    Map<string | void, { value: UnloadedDescriptor | null }>,
+  > = new Map();
+
+  const descriptors = [];
+
+  for (const item of items) {
+    if (typeof item.value === "function") {
+      const fnKey = item.value;
+      let nameMap = map.get(fnKey);
+      if (!nameMap) {
+        nameMap = new Map();
+        map.set(fnKey, nameMap);
+      }
+      let desc = nameMap.get(item.name);
+      if (!desc) {
+        desc = { value: null };
+        descriptors.push(desc);
+
+        // Treat passPerPreset presets as unique, skipping them
+        // in the merge processing steps.
+        if (!item.ownPass) nameMap.set(item.name, desc);
+      }
+
+      if (item.options === false) {
+        desc.value = null;
+      } else {
+        desc.value = item;
+      }
+    } else {
+      descriptors.push({ value: item });
+    }
+  }
+
+  return descriptors.reduce((acc, desc) => {
+    if (desc.value) acc.push(desc.value);
+    return acc;
+  }, []);
+}
+
+/**
+ * Tests if a filename should be ignored based on "ignore" and "only" options.
+ */
+function shouldIgnore(
+  context: ConfigContext,
+  ignore: ?IgnoreList,
+  only: ?IgnoreList,
+  dirname: string,
+): boolean {
+  if (context.filename === null) return false;
+  // $FlowIgnore - Flow refinements aren't quite smart enough for this :(
+  const ctx: ConfigContextNamed = context;
+
+  if (ignore) {
+    if (matchesPatterns(ctx, ignore, dirname)) {
+      debug(
+        "Ignored %o because it matched one of %O from %o",
+        context.filename,
+        ignore,
+        dirname,
+      );
+      return true;
+    }
+  }
+
+  if (only) {
+    if (!matchesPatterns(ctx, only, dirname)) {
+      debug(
+        "Ignored %o because it failed to match one of %O from %o",
+        context.filename,
+        only,
+        dirname,
+      );
+      return true;
+    }
+  }
+
+  return false;
+}
+
+/**
+ * Returns result of calling function with filename if pattern is a function.
+ * Otherwise returns result of matching pattern Regex with filename.
+ */
+function matchesPatterns(
+  context: ConfigContextNamed,
+  patterns: IgnoreList,
+  dirname: string,
+): boolean {
+  const res = [];
+  const strings = [];
+  const fns = [];
+
+  patterns.forEach(pattern => {
+    if (typeof pattern === "string") strings.push(pattern);
+    else if (typeof pattern === "function") fns.push(pattern);
+    else res.push(pattern);
+  });
+
+  const filename = context.filename;
+  if (res.some(re => re.test(context.filename))) return true;
+  if (fns.some(fn => fn(filename))) return true;
+
+  if (strings.length > 0) {
+    const possibleDirs = getPossibleDirs(context);
+
+    const absolutePatterns = strings.map(pattern => {
+      // Preserve the "!" prefix so that micromatch can use it for negation.
+      const negate = pattern[0] === "!";
+      if (negate) pattern = pattern.slice(1);
+
+      return (negate ? "!" : "") + path.resolve(dirname, pattern);
+    });
+
+    if (
+      micromatch(possibleDirs, absolutePatterns, { nocase: true }).length > 0
+    ) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+const getPossibleDirs = makeWeakCache((context: ConfigContextNamed) => {
+  let current = context.filename;
+  if (current === null) return [];
+
+  const possibleDirs = [current];
+  while (true) {
+    const previous = current;
+    current = path.dirname(current);
+    if (previous === current) break;
+
+    possibleDirs.push(current);
+  }
+
+  return possibleDirs;
+});

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

@@ -0,0 +1,272 @@
+// @flow
+
+import { loadPlugin, loadPreset } from "./files";
+
+import {
+  makeWeakCache,
+  makeStrongCache,
+  type CacheConfigurator,
+} from "./caching";
+
+import type {
+  ValidatedOptions,
+  PluginList,
+  PluginItem,
+} from "./validation/options";
+
+// Represents a config object and functions to lazily load the descriptors
+// for the plugins and presets so we don't load the plugins/presets unless
+// the options object actually ends up being applicable.
+export type OptionsAndDescriptors = {
+  options: ValidatedOptions,
+  plugins: () => Array<UnloadedDescriptor>,
+  presets: () => Array<UnloadedDescriptor>,
+};
+
+// Represents a plugin or presets at a given location in a config object.
+// At this point these have been resolved to a specific object or function,
+// but have not yet been executed to call functions with options.
+export type UnloadedDescriptor = {
+  name: string | void,
+  value: {} | Function,
+  options: {} | void | false,
+  dirname: string,
+  alias: string,
+  ownPass?: boolean,
+};
+
+export type ValidatedFile = {
+  filepath: string,
+  dirname: string,
+  options: ValidatedOptions,
+};
+
+/**
+ * Create a set of descriptors from a given options object, preserving
+ * descriptor identity based on the identity of the plugin/preset arrays
+ * themselves.
+ */
+export function createCachedDescriptors(
+  dirname: string,
+  options: ValidatedOptions,
+  alias: string,
+): OptionsAndDescriptors {
+  const { plugins, presets, passPerPreset } = options;
+  return {
+    options,
+    plugins: plugins
+      ? () => createCachedPluginDescriptors(plugins, dirname)(alias)
+      : () => [],
+    presets: presets
+      ? () =>
+          createCachedPresetDescriptors(presets, dirname)(alias)(
+            !!passPerPreset,
+          )
+      : () => [],
+  };
+}
+
+/**
+ * Create a set of descriptors from a given options object, with consistent
+ * identity for the descriptors, but not caching based on any specific identity.
+ */
+export function createUncachedDescriptors(
+  dirname: string,
+  options: ValidatedOptions,
+  alias: string,
+): OptionsAndDescriptors {
+  // The returned result here is cached to represent a config object in
+  // memory, so we build and memoize the descriptors to ensure the same
+  // values are returned consistently.
+  let plugins;
+  let presets;
+
+  return {
+    options,
+    plugins: () => {
+      if (!plugins) {
+        plugins = createPluginDescriptors(
+          options.plugins || [],
+          dirname,
+          alias,
+        );
+      }
+      return plugins;
+    },
+    presets: () => {
+      if (!presets) {
+        presets = createPresetDescriptors(
+          options.presets || [],
+          dirname,
+          alias,
+          !!options.passPerPreset,
+        );
+      }
+      return presets;
+    },
+  };
+}
+
+const createCachedPresetDescriptors = makeWeakCache(
+  (items: PluginList, cache: CacheConfigurator<string>) => {
+    const dirname = cache.using(dir => dir);
+    return makeStrongCache((alias: string) =>
+      makeStrongCache((passPerPreset: boolean) =>
+        createPresetDescriptors(items, dirname, alias, passPerPreset),
+      ),
+    );
+  },
+);
+
+const createCachedPluginDescriptors = makeWeakCache(
+  (items: PluginList, cache: CacheConfigurator<string>) => {
+    const dirname = cache.using(dir => dir);
+    return makeStrongCache((alias: string) =>
+      createPluginDescriptors(items, dirname, alias),
+    );
+  },
+);
+
+function createPresetDescriptors(
+  items: PluginList,
+  dirname: string,
+  alias: string,
+  passPerPreset: boolean,
+): Array<UnloadedDescriptor> {
+  return createDescriptors("preset", items, dirname, alias, passPerPreset);
+}
+
+function createPluginDescriptors(
+  items: PluginList,
+  dirname: string,
+  alias: string,
+): Array<UnloadedDescriptor> {
+  return createDescriptors("plugin", items, dirname, alias);
+}
+
+function createDescriptors(
+  type: "plugin" | "preset",
+  items: PluginList,
+  dirname: string,
+  alias: string,
+  ownPass?: boolean,
+): Array<UnloadedDescriptor> {
+  const descriptors = items.map((item, index) =>
+    createDescriptor(
+      item,
+      type === "plugin" ? loadPlugin : loadPreset,
+      dirname,
+      {
+        index,
+        alias,
+        ownPass: !!ownPass,
+      },
+    ),
+  );
+
+  assertNoDuplicates(descriptors);
+
+  return descriptors;
+}
+
+/**
+ * Given a plugin/preset item, resolve it into a standard format.
+ */
+function createDescriptor(
+  pair: PluginItem,
+  resolver,
+  dirname,
+  {
+    index,
+    alias,
+    ownPass,
+  }: {
+    index: number,
+    alias: string,
+    ownPass?: boolean,
+  },
+): UnloadedDescriptor {
+  let name;
+  let options;
+  let value = pair;
+  if (Array.isArray(value)) {
+    if (value.length === 3) {
+      // $FlowIgnore - Flow doesn't like the multiple tuple types.
+      [value, options, name] = value;
+    } else {
+      [value, options] = value;
+    }
+  }
+
+  let filepath = null;
+  if (typeof value === "string") {
+    ({ filepath, value } = resolver(value, dirname));
+  }
+
+  if (!value) {
+    throw new Error(`Unexpected falsy value: ${String(value)}`);
+  }
+
+  if (typeof value === "object" && value.__esModule) {
+    if (value.default) {
+      value = value.default;
+    } else {
+      throw new Error("Must export a default export when using ES6 modules.");
+    }
+  }
+
+  if (typeof value !== "object" && typeof value !== "function") {
+    throw new Error(
+      `Unsupported format: ${typeof value}. Expected an object or a function.`,
+    );
+  }
+
+  if (filepath !== null && typeof value === "object" && value) {
+    // We allow object values for plugins/presets nested directly within a
+    // config object, because it can be useful to define them in nested
+    // configuration contexts.
+    throw new Error(
+      "Plugin/Preset files are not allowed to export objects, only functions.",
+    );
+  }
+
+  return {
+    name,
+    alias: filepath || `${alias}$${index}`,
+    value,
+    options,
+    dirname,
+    ownPass,
+  };
+}
+
+function assertNoDuplicates(items: Array<UnloadedDescriptor>): void {
+  const map = new Map();
+
+  for (const item of items) {
+    if (typeof item.value !== "function") continue;
+
+    let nameMap = map.get(item.value);
+    if (!nameMap) {
+      nameMap = new Set();
+      map.set(item.value, nameMap);
+    }
+
+    if (nameMap.has(item.name)) {
+      throw new Error(
+        [
+          `Duplicate plugin/preset detected.`,
+          `If you'd like to use two separate instances of a plugin,`,
+          `they neen separate names, e.g.`,
+          ``,
+          `  plugins: [`,
+          `    ['some-plugin', {}],`,
+          `    ['some-plugin', {}, 'some unique name'],`,
+          `  ]`,
+        ].join("\n"),
+      );
+    }
+
+    nameMap.add(item.name);
+  }
+}

packages/babel-core/src/config/files/configuration.js

@@ -0,0 +1,294 @@
+// @flow
+
+import buildDebug from "debug";
+import path from "path";
+import fs from "fs";
+import json5 from "json5";
+import resolve from "resolve";
+import { makeStrongCache, type CacheConfigurator } from "../caching";
+
+const debug = buildDebug("babel:config:loading:files:configuration");
+
+export type ConfigFile = {
+  filepath: string,
+  dirname: string,
+  options: {},
+};
+
+export type IgnoreFile = {
+  filepath: string,
+  dirname: string,
+  ignore: Array<string>,
+};
+
+const BABELRC_FILENAME = ".babelrc";
+const BABELRC_JS_FILENAME = ".babelrc.js";
+const PACKAGE_FILENAME = "package.json";
+const BABELIGNORE_FILENAME = ".babelignore";
+
+export function findBabelrc(
+  filepath: string,
+  envName: string,
+): ConfigFile | null {
+  const dirname = path.dirname(filepath);
+  let loc = dirname;
+  while (true) {
+    const conf = [
+      BABELRC_FILENAME,
+      BABELRC_JS_FILENAME,
+      PACKAGE_FILENAME,
+    ].reduce((previousConfig: ConfigFile | null, name) => {
+      const filepath = path.join(loc, name);
+      const config = readConfig(filepath, envName);
+
+      if (config && previousConfig) {
+        throw new Error(
+          `Multiple configuration files found. Please remove one:\n` +
+            ` - ${path.basename(previousConfig.filepath)}\n` +
+            ` - ${name}\n` +
+            `from ${loc}`,
+        );
+      }
+
+      return config || previousConfig;
+    }, null);
+
+    if (conf) {
+      debug("Found configuration %o from %o.", conf.filepath, dirname);
+      return conf;
+    }
+
+    const nextLoc = path.dirname(loc);
+    if (loc === nextLoc) break;
+    loc = nextLoc;
+  }
+
+  return null;
+}
+
+export function findBabelignore(filepath: string): IgnoreFile | null {
+  const dirname = path.dirname(filepath);
+  let loc = dirname;
+  while (true) {
+    const ignoreLoc = path.join(loc, BABELIGNORE_FILENAME);
+    const ignore = readIgnoreConfig(ignoreLoc);
+
+    if (ignore) {
+      debug("Found ignore %o from %o.", ignore.filepath, dirname);
+      return ignore;
+    }
+
+    const nextLoc = path.dirname(loc);
+    if (loc === nextLoc) break;
+    loc = nextLoc;
+  }
+
+  return null;
+}
+
+export function loadConfig(
+  name: string,
+  dirname: string,
+  envName: string,
+): ConfigFile {
+  const filepath = resolve.sync(name, { basedir: dirname });
+
+  const conf = readConfig(filepath, envName);
+  if (!conf) {
+    throw new Error(`Config file ${filepath} contains no configuration data`);
+  }
+
+  debug("Loaded config %o from $o.", name, dirname);
+  return conf;
+}
+
+/**
+ * Read the given config file, returning the result. Returns null if no config was found, but will
+ * throw if there are parsing errors while loading a config.
+ */
+function readConfig(filepath, envName) {
+  return path.extname(filepath) === ".js"
+    ? readConfigJS(filepath, { envName })
+    : readConfigFile(filepath);
+}
+
+const LOADING_CONFIGS = new Set();
+
+const readConfigJS = makeStrongCache(
+  (filepath, cache: CacheConfigurator<{ envName: string }>) => {
+    if (!fs.existsSync(filepath)) {
+      cache.forever();
+      return null;
+    }
+
+    // The `require()` call below can make this code reentrant if a require hook like @babel/register has been
+    // loaded into the system. That would cause Babel to attempt to compile the `.babelrc.js` file as it loads
+    // below. To cover this case, we auto-ignore re-entrant config processing.
+    if (LOADING_CONFIGS.has(filepath)) {
+      cache.never();
+
+      debug("Auto-ignoring usage of config %o.", filepath);
+      return {
+        filepath,
+        dirname: path.dirname(filepath),
+        options: {},
+      };
+    }
+
+    let options;
+    try {
+      LOADING_CONFIGS.add(filepath);
+
+      // $FlowIssue
+      const configModule = (require(filepath): mixed);
+      options =
+        configModule && configModule.__esModule
+          ? configModule.default || undefined
+          : configModule;
+    } catch (err) {
+      err.message = `${filepath}: Error while loading config - ${err.message}`;
+      throw err;
+    } finally {
+      LOADING_CONFIGS.delete(filepath);
+    }
+
+    if (typeof options === "function") {
+      options = options({
+        cache: cache.simple(),
+        // Expose ".env()" so people can easily get the same env that we expose using the "env" key.
+        env: () => cache.using(data => data.envName),
+        async: () => false,
+      });
+
+      if (!cache.configured()) throwConfigError();
+    }
+
+    if (!options || typeof options !== "object" || Array.isArray(options)) {
+      throw new Error(
+        `${filepath}: Configuration should be an exported JavaScript object.`,
+      );
+    }
+
+    if (typeof options.then === "function") {
+      throw new Error(
+        `You appear to be using an async configuration, ` +
+          `which your current version of Babel does not support. ` +
+          `We may add support for this in the future, ` +
+          `but if you're on the most recent version of @babel/core and still ` +
+          `seeing this error, then you'll need to synchronously return your config.`,
+      );
+    }
+
+    return {
+      filepath,
+      dirname: path.dirname(filepath),
+      options,
+    };
+  },
+);
+
+const readConfigFile = makeStaticFileCache((filepath, content) => {
+  let options;
+  if (path.basename(filepath) === PACKAGE_FILENAME) {
+    try {
+      options = JSON.parse(content).babel;
+    } catch (err) {
+      err.message = `${filepath}: Error while parsing JSON - ${err.message}`;
+      throw err;
+    }
+    if (!options) return null;
+  } else {
+    try {
+      options = json5.parse(content);
+    } catch (err) {
+      err.message = `${filepath}: Error while parsing config - ${err.message}`;
+      throw err;
+    }
+
+    if (!options) throw new Error(`${filepath}: No config detected`);
+  }
+
+  if (typeof options !== "object") {
+    throw new Error(`${filepath}: Config returned typeof ${typeof options}`);
+  }
+  if (Array.isArray(options)) {
+    throw new Error(`${filepath}: Expected config object but found array`);
+  }
+
+  return {
+    filepath,
+    dirname: path.dirname(filepath),
+    options,
+  };
+});
+
+const readIgnoreConfig = makeStaticFileCache((filepath, content) => {
+  const ignore = content
+    .split("\n")
+    .map(line => line.replace(/#(.*?)$/, "").trim())
+    .filter(line => !!line);
+
+  return {
+    filepath,
+    dirname: path.dirname(filepath),
+    ignore,
+  };
+});
+
+function makeStaticFileCache<T>(fn: (string, string) => T): string => T | null {
+  return makeStrongCache((filepath, cache) => {
+    if (cache.invalidate(() => fileMtime(filepath)) === null) {
+      cache.forever();
+      return null;
+    }
+
+    return fn(filepath, fs.readFileSync(filepath, "utf8"));
+  });
+}
+
+function fileMtime(filepath: string): number | null {
+  try {
+    return +fs.statSync(filepath).mtime;
+  } catch (e) {
+    if (e.code !== "ENOENT") throw e;
+  }
+
+  return null;
+}
+
+function throwConfigError() {
+  throw new Error(`\
+Caching was left unconfigured. Babel's plugins, presets, and .babelrc.js files can be configured
+for various types of caching, using the first param of their handler functions:
+
+module.exports = function(api) {
+  // The API exposes the following:
+
+  // Cache the returned value forever and don't call this function again.
+  api.cache(true);
+
+  // Don't cache at all. Not recommended because it will be very slow.
+  api.cache(false);
+
+  // Cached based on the value of some function. If this function returns a value different from
+  // a previously-encountered value, the plugins will re-evaluate.
+  var env = api.cache(() => process.env.NODE_ENV);
+
+  // If testing for a specific env, we recommend specifics to avoid instantiating a plugin for
+  // any possible NODE_ENV value that might come up during plugin execution.
+  var isProd = api.cache(() => process.env.NODE_ENV === "production");
+
+  // .cache(fn) will perform a linear search though instances to find the matching plugin based
+  // based on previous instantiated plugins. If you want to recreate the plugin and discard the
+  // previous instance whenever something changes, you may use:
+  var isProd = api.cache.invalidate(() => process.env.NODE_ENV === "production");
+
+  // Note, we also expose the following more-verbose versions of the above examples:
+  api.cache.forever(); // api.cache(true)
+  api.cache.never();   // api.cache(false)
+  api.cache.using(fn); // api.cache(fn)
+
+  // Return the value that will be cached.
+  return { };
+};`);
+}

packages/babel-core/src/config/files/index-browser.js

@@ -6,9 +6,22 @@ export type ConfigFile = {
   options: {},
 };
 
+export type IgnoreFile = {
+  filepath: string,
+  dirname: string,
+  ignore: Array<string>,
+};
+
+export function findBabelrc(
+  filepath: string,
+  envName: string, // eslint-disable-line no-unused-vars
+): ConfigFile | null {
+  return null;
+}
+
 // eslint-disable-next-line no-unused-vars
-export function findConfigs(dirname: string): Array<ConfigFile> {
-  return [];
+export function findBabelignore(filepath: string): IgnoreFile | null {
+  return null;
 }
 
 export function loadConfig(name: string, dirname: string): ConfigFile {

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

@@ -1,9 +1,31 @@
 // @flow
 
-import type Plugin from "./plugin";
-import manageOptions from "./option-manager";
+import path from "path";
+import * as context from "../index";
+import Plugin from "./plugin";
+import merge from "lodash/merge";
+import {
+  buildRootChain,
+  buildPresetChain,
+  type ConfigChain,
+  type PresetInstance,
+} from "./config-chain";
+import type { UnloadedDescriptor } from "./config-descriptors";
+import traverse from "@babel/traverse";
+import clone from "lodash/clone";
+import { makeWeakCache, type CacheConfigurator } from "./caching";
+import { getEnv } from "./helpers/environment";
+import { validate } from "./validation/options";
+import { validatePluginObject } from "./validation/plugins";
 
-export type { InputOptions } from "./options";
+type LoadedDescriptor = {
+  value: {},
+  options: {},
+  dirname: string,
+  alias: string,
+};
+
+export type { InputOptions } from "./validation/options";
 
 export type ResolvedConfig = {
   options: Object,
@@ -14,13 +36,257 @@ export type { Plugin };
 export type PluginPassList = Array<Plugin>;
 export type PluginPasses = Array<PluginPassList>;
 
-/**
- * Standard API for loading Babel configuration data. Not for public consumption.
- */
-export default function loadConfig(opts: mixed): ResolvedConfig | null {
-  if (opts != null && (typeof opts !== "object" || Array.isArray(opts))) {
+export default function loadConfig(inputOpts: mixed): ResolvedConfig | null {
+  if (
+    inputOpts != null &&
+    (typeof inputOpts !== "object" || Array.isArray(inputOpts))
+  ) {
     throw new Error("Babel options must be an object, null, or undefined");
   }
 
-  return manageOptions(opts || {});
+  const args = inputOpts ? validate("arguments", inputOpts) : {};
+
+  const { envName = getEnv(), cwd = "." } = args;
+  const absoluteCwd = path.resolve(cwd);
+
+  const configChain = buildRootChain(absoluteCwd, args, envName);
+  if (!configChain) return null;
+
+  const optionDefaults = {};
+  const options = {};
+  const passes = [[]];
+  try {
+    (function recurseDescriptors(
+      config: {
+        plugins: Array<UnloadedDescriptor>,
+        presets: Array<UnloadedDescriptor>,
+      },
+      pass: Array<Plugin>,
+      envName: string,
+    ) {
+      const plugins = config.plugins.map(descriptor =>
+        loadPluginDescriptor(descriptor, envName),
+      );
+      const presets = config.presets.map(descriptor => {
+        return {
+          preset: loadPresetDescriptor(descriptor, envName),
+          pass: descriptor.ownPass ? [] : pass,
+        };
+      });
+
+      // resolve presets
+      if (presets.length > 0) {
+        // The passes are created in the same order as the preset list, but are inserted before any
+        // existing additional passes.
+        passes.splice(
+          1,
+          0,
+          ...presets.map(o => o.pass).filter(p => p !== pass),
+        );
+
+        for (const { preset, pass } of presets) {
+          recurseDescriptors(
+            {
+              plugins: preset.plugins,
+              presets: preset.presets,
+            },
+            pass,
+            envName,
+          );
+
+          preset.options.forEach(opts => {
+            merge(optionDefaults, opts);
+          });
+        }
+      }
+
+      // resolve plugins
+      if (plugins.length > 0) {
+        pass.unshift(...plugins);
+      }
+    })(
+      {
+        plugins: configChain.plugins,
+        presets: configChain.presets,
+      },
+      passes[0],
+      envName,
+    );
+
+    configChain.options.forEach(opts => {
+      merge(options, opts);
+    });
+  } catch (e) {
+    // There are a few case where thrown errors will try to annotate themselves multiple times, so
+    // to keep things simple we just bail out if re-wrapping the message.
+    if (!/^\[BABEL\]/.test(e.message)) {
+      e.message = `[BABEL] ${args.filename || "unknown"}: ${e.message}`;
+    }
+
+    throw e;
+  }
+
+  const opts: Object = merge(optionDefaults, options);
+
+  // Tack the passes onto the object itself so that, if this object is passed back to Babel a second time,
+  // it will be in the right structure to not change behavior.
+  opts.babelrc = false;
+  opts.plugins = passes[0];
+  opts.presets = passes
+    .slice(1)
+    .filter(plugins => plugins.length > 0)
+    .map(plugins => ({ plugins }));
+  opts.passPerPreset = opts.presets.length > 0;
+  opts.envName = envName;
+  opts.cwd = absoluteCwd;
+
+  return {
+    options: opts,
+    passes: passes,
+  };
+}
+
+/**
+ * Load a generic plugin/preset from the given descriptor loaded from the config object.
+ */
+const loadDescriptor = makeWeakCache(
+  (
+    { value, options, dirname, alias }: UnloadedDescriptor,
+    cache: CacheConfigurator<{ envName: string }>,
+  ): LoadedDescriptor => {
+    // Disabled presets should already have been filtered out
+    if (options === false) throw new Error("Assertion failure");
+
+    options = options || {};
+
+    let item = value;
+    if (typeof value === "function") {
+      const api = Object.assign(Object.create(context), {
+        cache: cache.simple(),
+        env: () => cache.using(data => data.envName),
+        async: () => false,
+      });
+
+      try {
+        item = value(api, options, dirname);
+      } catch (e) {
+        if (alias) {
+          e.message += ` (While processing: ${JSON.stringify(alias)})`;
+        }
+        throw e;
+      }
+    }
+
+    if (!item || typeof item !== "object") {
+      throw new Error("Plugin/Preset did not return an object.");
+    }
+
+    if (typeof item.then === "function") {
+      throw new Error(
+        `You appear to be using an async plugin, ` +
+          `which your current version of Babel does not support.` +
+          `If you're using a published plugin, ` +
+          `you may need to upgrade your @babel/core version.`,
+      );
+    }
+
+    return { value: item, options, dirname, alias };
+  },
+);
+
+/**
+ * Instantiate a plugin for the given descriptor, returning the plugin/options pair.
+ */
+function loadPluginDescriptor(
+  descriptor: UnloadedDescriptor,
+  envName: string,
+): Plugin {
+  if (descriptor.value instanceof Plugin) {
+    if (descriptor.options) {
+      throw new Error(
+        "Passed options to an existing Plugin instance will not work.",
+      );
+    }
+
+    return descriptor.value;
+  }
+
+  return instantiatePlugin(loadDescriptor(descriptor, { envName }), {
+    envName,
+  });
+}
+
+const instantiatePlugin = makeWeakCache(
+  (
+    { value, options, dirname, alias }: LoadedDescriptor,
+    cache: CacheConfigurator<{ envName: string }>,
+  ): Plugin => {
+    const pluginObj = validatePluginObject(value);
+
+    const plugin = Object.assign({}, pluginObj);
+    if (plugin.visitor) {
+      plugin.visitor = traverse.explode(clone(plugin.visitor));
+    }
+
+    if (plugin.inherits) {
+      const inheritsDescriptor = {
+        name: undefined,
+        alias: `${alias}$inherits`,
+        value: plugin.inherits,
+        options,
+        dirname,
+      };
+
+      // If the inherited plugin changes, reinstantiate this plugin.
+      const inherits = cache.invalidate(data =>
+        loadPluginDescriptor(inheritsDescriptor, data.envName),
+      );
+
+      plugin.pre = chain(inherits.pre, plugin.pre);
+      plugin.post = chain(inherits.post, plugin.post);
+      plugin.manipulateOptions = chain(
+        inherits.manipulateOptions,
+        plugin.manipulateOptions,
+      );
+      plugin.visitor = traverse.visitors.merge([
+        inherits.visitor || {},
+        plugin.visitor || {},
+      ]);
+    }
+
+    return new Plugin(plugin, options, alias);
+  },
+);
+
+/**
+ * Generate a config object that will act as the root of a new nested config.
+ */
+const loadPresetDescriptor = (
+  descriptor: UnloadedDescriptor,
+  envName: string,
+): ConfigChain => {
+  return buildPresetChain(
+    instantiatePreset(loadDescriptor(descriptor, { envName })),
+  );
+};
+
+const instantiatePreset = makeWeakCache(
+  ({ value, dirname, alias }: LoadedDescriptor): PresetInstance => {
+    return {
+      options: validate("preset", value),
+      alias,
+      dirname,
+    };
+  },
+);
+
+function chain(a, b) {
+  const fns = [a, b].filter(Boolean);
+  if (fns.length <= 1) return fns[0];
+
+  return function(...args) {
+    for (const fn of fns) {
+      fn.apply(this, args);
+    }
+  };
 }

packages/babel-core/src/config/loading/files/configuration.js

@@ -1,230 +0,0 @@
-// @flow
-
-import buildDebug from "debug";
-import path from "path";
-import fs from "fs";
-import json5 from "json5";
-import resolve from "resolve";
-import { getEnv } from "../../helpers/environment";
-import { makeStrongCache } from "../../caching";
-
-const debug = buildDebug("babel:config:loading:files:configuration");
-
-export type ConfigFile = {
-  filepath: string,
-  dirname: string,
-  options: {},
-};
-
-const BABELRC_FILENAME = ".babelrc";
-const BABELRC_JS_FILENAME = ".babelrc.js";
-const PACKAGE_FILENAME = "package.json";
-const BABELIGNORE_FILENAME = ".babelignore";
-
-export function findConfigs(dirname: string): Array<ConfigFile> {
-  let foundConfig = false;
-  let foundIgnore = false;
-
-  const confs = [];
-
-  let loc = dirname;
-  while (true) {
-    if (!foundIgnore) {
-      const ignoreLoc = path.join(loc, BABELIGNORE_FILENAME);
-      const ignore = readIgnoreConfig(ignoreLoc);
-
-      if (ignore) {
-        debug("Found ignore %o from %o.", ignore.filepath, dirname);
-        confs.push(ignore);
-        foundIgnore = true;
-      }
-    }
-
-    if (!foundConfig) {
-      const conf = [
-        BABELRC_FILENAME,
-        BABELRC_JS_FILENAME,
-        PACKAGE_FILENAME,
-      ].reduce((previousConfig: ConfigFile | null, name) => {
-        const filepath = path.join(loc, name);
-        const config = readConfig(filepath);
-
-        if (config && previousConfig) {
-          throw new Error(
-            `Multiple configuration files found. Please remove one:\n- ${path.basename(
-              previousConfig.filepath,
-            )}\n- ${name}\nfrom ${loc}`,
-          );
-        }
-
-        return config || previousConfig;
-      }, null);
-
-      if (conf) {
-        debug("Found configuration %o from %o.", conf.filepath, dirname);
-        confs.push(conf);
-        foundConfig = true;
-      }
-    }
-
-    if (foundIgnore && foundConfig) break;
-
-    if (loc === path.dirname(loc)) break;
-
-    loc = path.dirname(loc);
-  }
-
-  return confs;
-}
-
-export function loadConfig(name: string, dirname: string): ConfigFile {
-  const filepath = resolve.sync(name, { basedir: dirname });
-
-  const conf = readConfig(filepath);
-  if (!conf) {
-    throw new Error(`Config file ${filepath} contains no configuration data`);
-  }
-
-  debug("Loaded config %o from $o.", name, dirname);
-  return conf;
-}
-
-/**
- * Read the given config file, returning the result. Returns null if no config was found, but will
- * throw if there are parsing errors while loading a config.
- */
-function readConfig(filepath) {
-  return path.extname(filepath) === ".js"
-    ? readConfigJS(filepath)
-    : readConfigFile(filepath);
-}
-
-const LOADING_CONFIGS = new Set();
-const readConfigJS = makeStrongCache((filepath, cache) => {
-  if (!fs.existsSync(filepath)) {
-    cache.forever();
-    return null;
-  }
-
-  // The `require()` call below can make this code reentrant if a require hook like @babel/register has been
-  // loaded into the system. That would cause Babel to attempt to compile the `.babelrc.js` file as it loads
-  // below. To cover this case, we auto-ignore re-entrant config processing.
-  if (LOADING_CONFIGS.has(filepath)) {
-    cache.never();
-
-    debug("Auto-ignoring usage of config %o.", filepath);
-    return {
-      filepath,
-      dirname: path.dirname(filepath),
-      options: {},
-    };
-  }
-
-  let options;
-  try {
-    LOADING_CONFIGS.add(filepath);
-
-    // $FlowIssue
-    const configModule = (require(filepath): mixed);
-    options =
-      configModule && configModule.__esModule
-        ? configModule.default || undefined
-        : configModule;
-  } catch (err) {
-    err.message = `${filepath}: Error while loading config - ${err.message}`;
-    throw err;
-  } finally {
-    LOADING_CONFIGS.delete(filepath);
-  }
-
-  if (typeof options === "function") {
-    options = options({
-      cache,
-      // Expose ".env()" so people can easily get the same env that we expose using the "env" key.
-      env: () => cache.using(() => getEnv()),
-    });
-  } else {
-    cache.forever();
-  }
-
-  if (!options || typeof options !== "object" || Array.isArray(options)) {
-    throw new Error(
-      `${filepath}: Configuration should be an exported JavaScript object.`,
-    );
-  }
-
-  return {
-    filepath,
-    dirname: path.dirname(filepath),
-    options,
-  };
-}, false /* autoPermacache */);
-
-const readConfigFile = makeStaticFileCache((filepath, content) => {
-  let options;
-  if (path.basename(filepath) === PACKAGE_FILENAME) {
-    try {
-      options = JSON.parse(content).babel;
-    } catch (err) {
-      err.message = `${filepath}: Error while parsing JSON - ${err.message}`;
-      throw err;
-    }
-    if (!options) return null;
-  } else {
-    try {
-      options = json5.parse(content);
-    } catch (err) {
-      err.message = `${filepath}: Error while parsing config - ${err.message}`;
-      throw err;
-    }
-
-    if (!options) throw new Error(`${filepath}: No config detected`);
-  }
-
-  if (typeof options !== "object") {
-    throw new Error(`${filepath}: Config returned typeof ${typeof options}`);
-  }
-  if (Array.isArray(options)) {
-    throw new Error(`${filepath}: Expected config object but found array`);
-  }
-
-  return {
-    filepath,
-    dirname: path.dirname(filepath),
-    options,
-  };
-});
-
-const readIgnoreConfig = makeStaticFileCache((filepath, content) => {
-  const ignore = content
-    .split("\n")
-    .map(line => line.replace(/#(.*?)$/, "").trim())
-    .filter(line => !!line);
-
-  return {
-    filepath,
-    dirname: path.dirname(filepath),
-    options: { ignore },
-  };
-});
-
-function makeStaticFileCache<T>(fn: (string, string) => T): string => T | null {
-  return makeStrongCache((filepath, cache) => {
-    if (cache.invalidate(() => fileMtime(filepath)) === null) {
-      cache.forever();
-      return null;
-    }
-
-    return fn(filepath, fs.readFileSync(filepath, "utf8"));
-  });
-}
-
-function fileMtime(filepath: string): number | null {
-  try {
-    return +fs.statSync(filepath).mtime;
-  } catch (e) {
-    if (e.code !== "ENOENT") throw e;
-  }
-
-  return null;
-}

packages/babel-core/src/config/option-manager.js

@@ -1,362 +0,0 @@
-// @flow
-
-import * as context from "../index";
-import Plugin, { validatePluginObject } from "./plugin";
-import merge from "lodash/merge";
-import buildConfigChain, { type ConfigItem } from "./build-config-chain";
-import traverse from "@babel/traverse";
-import clone from "lodash/clone";
-import { makeWeakCache } from "./caching";
-import { getEnv } from "./helpers/environment";
-import { validate, type ValidatedOptions, type PluginItem } from "./options";
-
-import { loadPlugin, loadPreset } from "./loading/files";
-
-type MergeOptions =
-  | ConfigItem
-  | {
-      type: "preset",
-      options: ValidatedOptions,
-      alias: string,
-      dirname: string,
-    };
-
-export default function manageOptions(opts: {}): {
-  options: Object,
-  passes: Array<Array<Plugin>>,
-} | null {
-  return new OptionManager().init(opts);
-}
-
-class OptionManager {
-  constructor() {
-    this.options = {};
-    this.passes = [[]];
-  }
-
-  options: ValidatedOptions;
-  passes: Array<Array<Plugin>>;
-
-  /**
-   * This is called when we want to merge the input `opts` into the
-   * base options.
-   *
-   *  - `alias` is used to output pretty traces back to the original source.
-   *  - `loc` is used to point to the original config.
-   *  - `dirname` is used to resolve plugins relative to it.
-   */
-
-  mergeOptions(config: MergeOptions, pass?: Array<Plugin>) {
-    const result = loadConfig(config);
-
-    const plugins = result.plugins.map(descriptor =>
-      loadPluginDescriptor(descriptor),
-    );
-    const presets = result.presets.map(descriptor =>
-      loadPresetDescriptor(descriptor),
-    );
-
-    const passPerPreset = config.options.passPerPreset;
-    pass = pass || this.passes[0];
-
-    // resolve presets
-    if (presets.length > 0) {
-      let presetPasses = null;
-      if (passPerPreset) {
-        presetPasses = presets.map(() => []);
-        // The passes are created in the same order as the preset list, but are inserted before any
-        // existing additional passes.
-        this.passes.splice(1, 0, ...presetPasses);
-      }
-
-      presets.forEach((presetConfig, i) => {
-        this.mergeOptions(presetConfig, presetPasses ? presetPasses[i] : pass);
-      });
-    }
-
-    // resolve plugins
-    if (plugins.length > 0) {
-      pass.unshift(...plugins);
-    }
-
-    const options = Object.assign({}, result.options);
-    delete options.extends;
-    delete options.env;
-    delete options.plugins;
-    delete options.presets;
-    delete options.passPerPreset;
-
-    // "sourceMap" is just aliased to sourceMap, so copy it over as
-    // we merge the options together.
-    if (options.sourceMap) {
-      options.sourceMaps = options.sourceMap;
-      delete options.sourceMap;
-    }
-
-    merge(this.options, options);
-  }
-
-  init(inputOpts: {}) {
-    const args = validate("arguments", inputOpts);
-
-    const configChain = buildConfigChain(args);
-    if (!configChain) return null;
-
-    try {
-      for (const config of configChain) {
-        this.mergeOptions(config);
-      }
-    } catch (e) {
-      // There are a few case where thrown errors will try to annotate themselves multiple times, so
-      // to keep things simple we just bail out if re-wrapping the message.
-      if (!/^\[BABEL\]/.test(e.message)) {
-        e.message = `[BABEL] ${args.filename || "unknown"}: ${e.message}`;
-      }
-
-      throw e;
-    }
-
-    const opts: Object = this.options;
-
-    // Tack the passes onto the object itself so that, if this object is passed back to Babel a second time,
-    // it will be in the right structure to not change behavior.
-    opts.babelrc = false;
-    opts.plugins = this.passes[0];
-    opts.presets = this.passes
-      .slice(1)
-      .filter(plugins => plugins.length > 0)
-      .map(plugins => ({ plugins }));
-    opts.passPerPreset = opts.presets.length > 0;
-
-    return {
-      options: opts,
-      passes: this.passes,
-    };
-  }
-}
-
-type BasicDescriptor = {
-  value: {} | Function,
-  options: {} | void,
-  dirname: string,
-  alias: string,
-};
-
-type LoadedDescriptor = {
-  value: {},
-  options: {},
-  dirname: string,
-  alias: string,
-};
-
-/**
- * Load and validate the given config into a set of options, plugins, and presets.
- */
-const loadConfig = makeWeakCache((config: MergeOptions): {
-  options: {},
-  plugins: Array<BasicDescriptor>,
-  presets: Array<BasicDescriptor>,
-} => {
-  const options = config.options;
-
-  const plugins = (config.options.plugins || []).map((plugin, index) =>
-    createDescriptor(plugin, loadPlugin, config.dirname, {
-      index,
-      alias: config.alias,
-    }),
-  );
-
-  const presets = (config.options.presets || []).map((preset, index) =>
-    createDescriptor(preset, loadPreset, config.dirname, {
-      index,
-      alias: config.alias,
-    }),
-  );
-
-  return { options, plugins, presets };
-});
-
-/**
- * Load a generic plugin/preset from the given descriptor loaded from the config object.
- */
-const loadDescriptor = makeWeakCache(
-  (
-    { value, options = {}, dirname, alias }: BasicDescriptor,
-    cache,
-  ): LoadedDescriptor => {
-    let item = value;
-    if (typeof value === "function") {
-      const api = Object.assign(Object.create(context), {
-        cache,
-        env: () => cache.using(() => getEnv()),
-      });
-
-      try {
-        item = value(api, options, dirname);
-      } catch (e) {
-        if (alias) {
-          e.message += ` (While processing: ${JSON.stringify(alias)})`;
-        }
-        throw e;
-      }
-    }
-
-    if (!item || typeof item !== "object") {
-      throw new Error("Plugin/Preset did not return an object.");
-    }
-
-    return { value: item, options, dirname, alias };
-  },
-);
-
-/**
- * Instantiate a plugin for the given descriptor, returning the plugin/options pair.
- */
-function loadPluginDescriptor(descriptor: BasicDescriptor): Plugin {
-  if (descriptor.value instanceof Plugin) {
-    if (descriptor.options) {
-      throw new Error(
-        "Passed options to an existing Plugin instance will not work.",
-      );
-    }
-
-    return descriptor.value;
-  }
-
-  return instantiatePlugin(loadDescriptor(descriptor));
-}
-
-const instantiatePlugin = makeWeakCache(
-  ({ value, options, dirname, alias }: LoadedDescriptor, cache): Plugin => {
-    const pluginObj = validatePluginObject(value);
-
-    const plugin = Object.assign({}, pluginObj);
-    if (plugin.visitor) {
-      plugin.visitor = traverse.explode(clone(plugin.visitor));
-    }
-
-    if (plugin.inherits) {
-      const inheritsDescriptor = {
-        alias: `${alias}$inherits`,
-        value: plugin.inherits,
-        options,
-        dirname,
-      };
-
-      // If the inherited plugin changes, reinstantiate this plugin.
-      const inherits = cache.invalidate(() =>
-        loadPluginDescriptor(inheritsDescriptor),
-      );
-
-      plugin.pre = chain(inherits.pre, plugin.pre);
-      plugin.post = chain(inherits.post, plugin.post);
-      plugin.manipulateOptions = chain(
-        inherits.manipulateOptions,
-        plugin.manipulateOptions,
-      );
-      plugin.visitor = traverse.visitors.merge([
-        inherits.visitor || {},
-        plugin.visitor || {},
-      ]);
-    }
-
-    return new Plugin(plugin, options, alias);
-  },
-);
-
-/**
- * Generate a config object that will act as the root of a new nested config.
- */
-const loadPresetDescriptor = (descriptor: BasicDescriptor): MergeOptions => {
-  return instantiatePreset(loadDescriptor(descriptor));
-};
-
-const instantiatePreset = makeWeakCache(
-  ({ value, dirname, alias }: LoadedDescriptor): MergeOptions => {
-    return {
-      type: "preset",
-      options: validate("preset", value),
-      alias,
-      dirname,
-    };
-  },
-);
-
-/**
- * Given a plugin/preset item, resolve it into a standard format.
- */
-function createDescriptor(
-  pair: PluginItem,
-  resolver,
-  dirname,
-  {
-    index,
-    alias,
-  }: {
-    index: number,
-    alias: string,
-  },
-): BasicDescriptor {
-  let options;
-  let value = pair;
-  if (Array.isArray(value)) {
-    [value, options] = value;
-  }
-
-  let filepath = null;
-  if (typeof value === "string") {
-    ({ filepath, value } = resolver(value, dirname));
-  }
-
-  if (!value) {
-    throw new Error(`Unexpected falsy value: ${String(value)}`);
-  }
-
-  if (typeof value === "object" && value.__esModule) {
-    if (value.default) {
-      value = value.default;
-    } else {
-      throw new Error("Must export a default export when using ES6 modules.");
-    }
-  }
-
-  if (typeof value !== "object" && typeof value !== "function") {
-    throw new Error(
-      `Unsupported format: ${typeof value}. Expected an object or a function.`,
-    );
-  }
-
-  if (filepath !== null && typeof value === "object" && value) {
-    // We allow object values for plugins/presets nested directly within a
-    // config object, because it can be useful to define them in nested
-    // configuration contexts.
-    throw new Error(
-      "Plugin/Preset files are not allowed to export objects, only functions.",
-    );
-  }
-
-  if (options != null && typeof options !== "object") {
-    throw new Error(
-      "Plugin/Preset options must be an object, null, or undefined",
-    );
-  }
-  options = options || undefined;
-
-  return {
-    alias: filepath || `${alias}$${index}`,
-    value,
-    options,
-    dirname,
-  };
-}
-
-function chain(a, b) {
-  const fns = [a, b].filter(Boolean);
-  if (fns.length <= 1) return fns[0];
-
-  return function(...args) {
-    for (const fn of fns) {
-      fn.apply(this, args);
-    }
-  };
-}

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

@@ -1,100 +1,6 @@
 // @flow
 
-import {
-  assertString,
-  assertFunction,
-  assertObject,
-  type ValidatorSet,
-  type Validator,
-} from "./option-assertions";
-
-// Note: The casts here are just meant to be static assertions to make sure
-// that the assertion functions actually assert that the value's type matches
-// the declared types.
-const VALIDATORS: ValidatorSet = {
-  name: (assertString: Validator<$PropertyType<PluginObject, "name">>),
-  manipulateOptions: (assertFunction: Validator<
-    $PropertyType<PluginObject, "manipulateOptions">,
-  >),
-  pre: (assertFunction: Validator<$PropertyType<PluginObject, "pre">>),
-  post: (assertFunction: Validator<$PropertyType<PluginObject, "post">>),
-  inherits: (assertFunction: Validator<
-    $PropertyType<PluginObject, "inherits">,
-  >),
-  visitor: (assertVisitorMap: Validator<
-    $PropertyType<PluginObject, "visitor">,
-  >),
-
-  parserOverride: (assertFunction: Validator<
-    $PropertyType<PluginObject, "parserOverride">,
-  >),
-  generatorOverride: (assertFunction: Validator<
-    $PropertyType<PluginObject, "generatorOverride">,
-  >),
-};
-
-function assertVisitorMap(key: string, value: mixed): VisitorMap {
-  const obj = assertObject(key, value);
-  if (obj) {
-    Object.keys(obj).forEach(prop => assertVisitorHandler(prop, obj[prop]));
-
-    if (obj.enter || obj.exit) {
-      throw new Error(
-        `.${key} cannot contain catch-all "enter" or "exit" handlers. Please target individual nodes.`,
-      );
-    }
-  }
-  return (obj: any);
-}
-
-function assertVisitorHandler(
-  key: string,
-  value: mixed,
-): VisitorHandler | void {
-  if (value && typeof value === "object") {
-    Object.keys(value).forEach(handler => {
-      if (handler !== "enter" && handler !== "exit") {
-        throw new Error(
-          `.visitor["${key}"] may only have .enter and/or .exit handlers.`,
-        );
-      }
-    });
-  } else if (typeof value !== "function") {
-    throw new Error(`.visitor["${key}"] must be a function`);
-  }
-
-  return (value: any);
-}
-
-type VisitorHandler = Function | { enter?: Function, exit?: Function };
-export type VisitorMap = {
-  [string]: VisitorHandler,
-};
-
-export type PluginObject = {
-  name?: string,
-  manipulateOptions?: Function,
-
-  pre?: Function,
-  post?: Function,
-
-  inherits?: Function,
-  visitor?: VisitorMap,
-
-  parserOverride?: Function,
-  generatorOverride?: Function,
-};
-
-export function validatePluginObject(obj: {}): PluginObject {
-  Object.keys(obj).forEach(key => {
-    const validator = VALIDATORS[key];
-
-    if (validator) validator(key, obj[key]);
-    else throw new Error(`.${key} is not a valid Plugin property`);
-  });
-
-  return (obj: any);
-}
+import type { PluginObject } from "./validation/plugins";
 
 export default class Plugin {
   key: ?string;

packages/babel-core/src/config/validation/option-assertions.js

@@ -146,16 +146,31 @@ function assertPluginItem(
     if (value.length === 0) {
       throw new Error(`.${key}[${index}] must include an object`);
     }
-    if (value.length > 2) {
-      throw new Error(`.${key}[${index}] may only be a two-tuple`);
+
+    if (value.length > 3) {
+      throw new Error(
+        `.${key}[${index}] may only be a two-tuple or three-tuple`,
+      );
     }
 
     assertPluginTarget(key, index, true, value[0]);
 
-    if (value.length === 2) {
+    if (value.length > 1) {
       const opts = value[1];
-      if (opts != null && (typeof opts !== "object" || Array.isArray(opts))) {
-        throw new Error(`.${key}[${index}][1] must be an object, or undefined`);
+      if (
+        opts !== undefined &&
+        opts !== false &&
+        (typeof opts !== "object" || Array.isArray(opts))
+      ) {
+        throw new Error(
+          `.${key}[${index}][1] must be an object, false, or undefined`,
+        );
+      }
+    }
+    if (value.length === 3) {
+      const name = value[2];
+      if (name !== undefined && typeof name !== "string") {
+        throw new Error(`.${key}[${index}][2] must be a string, or undefined`);
       }
     }
   } else {
@@ -176,9 +191,9 @@ function assertPluginTarget(
     typeof value !== "function"
   ) {
     throw new Error(
-      `.${key}[${index}]${inArray
-        ? `[0]`
-        : ""} must be a string, object, function`,
+      `.${key}[${index}]${
+        inArray ? `[0]` : ""
+      } must be a string, object, function`,
     );
   }
   return value;

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

@@ -17,6 +17,7 @@ import {
 } from "./option-assertions";
 
 const ROOT_VALIDATORS: ValidatorSet = {
+  cwd: (assertString: Validator<$PropertyType<ValidatedOptions, "cwd">>),
   filename: (assertString: Validator<
     $PropertyType<ValidatedOptions, "filename">,
   >),
@@ -28,6 +29,10 @@ const ROOT_VALIDATORS: ValidatorSet = {
   >),
   code: (assertBoolean: Validator<$PropertyType<ValidatedOptions, "code">>),
   ast: (assertBoolean: Validator<$PropertyType<ValidatedOptions, "ast">>),
+
+  envName: (assertString: Validator<
+    $PropertyType<ValidatedOptions, "envName">,
+  >),
 };
 
 const NONPRESET_VALIDATORS: ValidatorSet = {
@@ -124,12 +129,14 @@ const COMMON_VALIDATORS: ValidatorSet = {
 export type InputOptions = ValidatedOptions;
 
 export type ValidatedOptions = {
+  cwd?: string,
   filename?: string,
   filenameRelative?: string,
   babelrc?: boolean,
   code?: boolean,
   ast?: boolean,
   inputSourceMap?: RootInputSourceMapOption,
+  envName?: string,
 
   extends?: string,
   env?: EnvSet<ValidatedOptions>,
@@ -180,8 +187,13 @@ export type EnvSet<T> = {
 export type IgnoreItem = string | Function | RegExp;
 export type IgnoreList = $ReadOnlyArray<IgnoreItem>;
 
+export type PluginOptions = {} | void | false;
 export type PluginTarget = string | {} | Function;
-export type PluginItem = PluginTarget | [PluginTarget, {} | void];
+export type PluginItem =
+  | Plugin
+  | PluginTarget
+  | [PluginTarget, PluginOptions]
+  | [PluginTarget, PluginOptions, string];
 export type PluginList = $ReadOnlyArray<PluginItem>;
 
 export type SourceMapsOption = boolean | "inline" | "both";
@@ -201,6 +213,9 @@ export function validate(type: OptionsType, opts: {}): ValidatedOptions {
     if (type !== "arguments" && ROOT_VALIDATORS[key]) {
       throw new Error(`.${key} is only allowed in root programmatic options`);
     }
+    if (type === "env" && key === "env") {
+      throw new Error(`.${key} is not allowed inside another env block`);
+    }
 
     const validator =
       COMMON_VALIDATORS[key] ||

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

@@ -0,0 +1,95 @@
+import {
+  assertString,
+  assertFunction,
+  assertObject,
+  type ValidatorSet,
+  type Validator,
+} from "./option-assertions";
+
+// Note: The casts here are just meant to be static assertions to make sure
+// that the assertion functions actually assert that the value's type matches
+// the declared types.
+const VALIDATORS: ValidatorSet = {
+  name: (assertString: Validator<$PropertyType<PluginObject, "name">>),
+  manipulateOptions: (assertFunction: Validator<
+    $PropertyType<PluginObject, "manipulateOptions">,
+  >),
+  pre: (assertFunction: Validator<$PropertyType<PluginObject, "pre">>),
+  post: (assertFunction: Validator<$PropertyType<PluginObject, "post">>),
+  inherits: (assertFunction: Validator<
+    $PropertyType<PluginObject, "inherits">,
+  >),
+  visitor: (assertVisitorMap: Validator<
+    $PropertyType<PluginObject, "visitor">,
+  >),
+
+  parserOverride: (assertFunction: Validator<
+    $PropertyType<PluginObject, "parserOverride">,
+  >),
+  generatorOverride: (assertFunction: Validator<
+    $PropertyType<PluginObject, "generatorOverride">,
+  >),
+};
+
+function assertVisitorMap(key: string, value: mixed): VisitorMap {
+  const obj = assertObject(key, value);
+  if (obj) {
+    Object.keys(obj).forEach(prop => assertVisitorHandler(prop, obj[prop]));
+
+    if (obj.enter || obj.exit) {
+      throw new Error(
+        `.${key} cannot contain catch-all "enter" or "exit" handlers. Please target individual nodes.`,
+      );
+    }
+  }
+  return (obj: any);
+}
+
+function assertVisitorHandler(
+  key: string,
+  value: mixed,
+): VisitorHandler | void {
+  if (value && typeof value === "object") {
+    Object.keys(value).forEach(handler => {
+      if (handler !== "enter" && handler !== "exit") {
+        throw new Error(
+          `.visitor["${key}"] may only have .enter and/or .exit handlers.`,
+        );
+      }
+    });
+  } else if (typeof value !== "function") {
+    throw new Error(`.visitor["${key}"] must be a function`);
+  }
+
+  return (value: any);
+}
+
+type VisitorHandler = Function | { enter?: Function, exit?: Function };
+export type VisitorMap = {
+  [string]: VisitorHandler,
+};
+
+export type PluginObject = {
+  name?: string,
+  manipulateOptions?: Function,
+
+  pre?: Function,
+  post?: Function,
+
+  inherits?: Function,
+  visitor?: VisitorMap,
+
+  parserOverride?: Function,
+  generatorOverride?: Function,
+};
+
+export function validatePluginObject(obj: {}): PluginObject {
+  Object.keys(obj).forEach(key => {
+    const validator = VALIDATORS[key];
+
+    if (validator) validator(key, obj[key]);
+    else throw new Error(`.${key} is not a valid Plugin property`);
+  });
+
+  return (obj: any);
+}

packages/babel-core/src/index.js

@@ -4,7 +4,7 @@ export { default as File } from "./transformation/file/file";
 export {
   default as buildExternalHelpers,
 } from "./tools/build-external-helpers";
-export { resolvePlugin, resolvePreset } from "./config/loading/files";
+export { resolvePlugin, resolvePreset } from "./config/files";
 
 export { version } from "../package.json";
 export { getEnv } from "./config/helpers/environment";

packages/babel-core/src/transform-file-sync.js

@@ -8,13 +8,14 @@ export default function transformFileSync(
   filename: string,
   opts: ?InputOptions,
 ): FileResult | null {
+  let options;
   if (opts == null) {
-    opts = { filename };
+    options = { filename };
   } else if (opts && typeof opts === "object") {
-    opts = Object.assign(opts, { filename });
+    options = Object.assign({}, opts, { filename });
   }
 
-  const config = loadConfig(opts);
+  const config = loadConfig(options);
   if (config === null) return null;
 
   return runSync(config, fs.readFileSync(filename, "utf8"));

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

@@ -10,21 +10,22 @@ type TransformFile = {
 };
 
 export default ((function transformFile(filename, opts, callback) {
+  let options;
   if (typeof opts === "function") {
     callback = opts;
     opts = undefined;
   }
 
   if (opts == null) {
-    opts = { filename };
+    options = { filename };
   } else if (opts && typeof opts === "object") {
-    opts = Object.assign(opts, { filename });
+    options = Object.assign({}, opts, { filename });
   }
 
   process.nextTick(() => {
     let cfg;
     try {
-      cfg = loadConfig(opts);
+      cfg = loadConfig(options);
       if (cfg === null) return callback(null, null);
     } catch (err) {
       return callback(err);

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

@@ -38,6 +38,15 @@ export default function generateCode(
     result = generate(ast, opts.generatorOpts, code);
   } else if (results.length === 1) {
     result = results[0];
+
+    if (typeof result.then === "function") {
+      throw new Error(
+        `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.`,
+      );
+    }
   } else {
     throw new Error("More than one plugin attempted to override codegen.");
   }

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

@@ -86,7 +86,18 @@ function transformFile(file: File, pluginPasses: PluginPasses): void {
 
     for (const [plugin, pass] of passPairs) {
       const fn = plugin.pre;
-      if (fn) fn.call(pass, file);
+      if (fn) {
+        const result = fn.call(pass, file);
+
+        if (isThenable(result)) {
+          throw new Error(
+            `You appear to be using an plugin with an async .pre, ` +
+              `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.`,
+          );
+        }
+      }
     }
 
     // merge all plugin visitors into a single visitor
@@ -99,7 +110,26 @@ function transformFile(file: File, pluginPasses: PluginPasses): void {
 
     for (const [plugin, pass] of passPairs) {
       const fn = plugin.post;
-      if (fn) fn.call(pass, file);
+      if (fn) {
+        const result = fn.call(pass, file);
+
+        if (isThenable(result)) {
+          throw new Error(
+            `You appear to be using an plugin with an async .post, ` +
+              `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.`,
+          );
+        }
+      }
     }
   }
 }
+
+function isThenable(val: mixed): boolean {
+  return (
+    !!val &&
+    (typeof val === "object" || typeof val === "function") &&
+    typeof val.then === "function"
+  );
+}

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

@@ -6,6 +6,7 @@ import convertSourceMap, { typeof Converter } from "convert-source-map";
 import { parse } from "babylon";
 import { codeFrameColumns } from "@babel/code-frame";
 import File from "./file/file";
+import generateMissingPluginMessage from "./util/missing-plugin-helper";
 
 const shebangRegex = /^#!.*/;
 
@@ -76,25 +77,39 @@ function parser(pluginPasses, options, code) {
     if (results.length === 0) {
       return parse(code, options.parserOpts);
     } else if (results.length === 1) {
+      if (typeof results[0].then === "function") {
+        throw new Error(
+          `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.`,
+        );
+      }
       return results[0];
     }
     throw new Error("More than one plugin attempted to override parsing.");
   } catch (err) {
-    const loc = err.loc;
+    const { loc, missingPlugin } = err;
     if (loc) {
       err.loc = null;
-      err.message =
-        `${options.filename || "unknown"}: ${err.message}\n` +
-        codeFrameColumns(
-          code,
-          {
-            start: {
-              line: loc.line,
-              column: loc.column + 1,
-            },
+      const codeFrame = codeFrameColumns(
+        code,
+        {
+          start: {
+            line: loc.line,
+            column: loc.column + 1,
           },
-          options,
-        );
+        },
+        options,
+      );
+      if (missingPlugin) {
+        err.message =
+          `${options.filename || "unknown"}: ` +
+          generateMissingPluginMessage(missingPlugin[0], loc, codeFrame);
+      } else {
+        err.message =
+          `${options.filename || "unknown"}: ${err.message}\n\n` + codeFrame;
+      }
     }
     throw err;
   }

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

@@ -41,9 +41,9 @@ export default function normalizeOptions(config: ResolvedConfig): {} {
         auxiliaryCommentAfter: opts.auxiliaryCommentAfter,
         retainLines: opts.retainLines,
         comments,
+        shouldPrintComment: opts.shouldPrintComment,
         compact,
         minified: opts.minified,
-        concise: opts.concise,
 
         // Source-map generation flags.
         sourceMaps,

packages/babel-core/src/transformation/util/missing-plugin-helper.js

@@ -0,0 +1,236 @@
+// @flow
+
+const pluginNameMap = {
+  asyncGenerators: {
+    syntax: {
+      name: "@babel/plugin-syntax-async-generators",
+      url: "https://git.io/vb4SY",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-async-generator-functions",
+      url: "https://git.io/vb4yp",
+    },
+  },
+  classProperties: {
+    syntax: {
+      name: "@babel/plugin-syntax-class-properties",
+      url: "https://git.io/vb4yQ",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-class-properties",
+      url: "https://git.io/vb4SL",
+    },
+  },
+  decorators: {
+    syntax: {
+      name: "@babel/plugin-syntax-decorators",
+      url: "https://git.io/vb4y9",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-decorators",
+      url: "https://git.io/vb4ST",
+    },
+  },
+  doExpressions: {
+    syntax: {
+      name: "@babel/plugin-syntax-do-expressions",
+      url: "https://git.io/vb4yh",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-do-expressions",
+      url: "https://git.io/vb4S3",
+    },
+  },
+  dynamicImport: {
+    syntax: {
+      name: "@babel/plugin-syntax-dynamic-import",
+      url: "https://git.io/vb4Sv",
+    },
+  },
+  exportDefaultFrom: {
+    syntax: {
+      name: "@babel/plugin-syntax-export-default-from",
+      url: "https://git.io/vb4SO",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-export-default-from",
+      url: "https://git.io/vb4yH",
+    },
+  },
+  exportNamespaceFrom: {
+    syntax: {
+      name: "@babel/plugin-syntax-export-namespace-from",
+      url: "https://git.io/vb4Sf",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-export-namespace-from",
+      url: "https://git.io/vb4SG",
+    },
+  },
+  flow: {
+    syntax: {
+      name: "@babel/plugin-syntax-flow",
+      url: "https://git.io/vb4yb",
+    },
+    transform: {
+      name: "@babel/plugin-transform-flow-strip-types",
+      url: "https://git.io/vb49g",
+    },
+  },
+  functionBind: {
+    syntax: {
+      name: "@babel/plugin-syntax-function-bind",
+      url: "https://git.io/vb4y7",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-function-bind",
+      url: "https://git.io/vb4St",
+    },
+  },
+  functionSent: {
+    syntax: {
+      name: "@babel/plugin-syntax-function-sent",
+      url: "https://git.io/vb4yN",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-function-sent",
+      url: "https://git.io/vb4SZ",
+    },
+  },
+  importMeta: {
+    syntax: {
+      name: "@babel/plugin-syntax-import-meta",
+      url: "https://git.io/vbKK6",
+    },
+  },
+  jsx: {
+    syntax: {
+      name: "@babel/plugin-syntax-jsx",
+      url: "https://git.io/vb4yA",
+    },
+    transform: {
+      name: "@babel/plugin-transform-react-jsx",
+      url: "https://git.io/vb4yd",
+    },
+  },
+  nullishCoalescingOperator: {
+    syntax: {
+      name: "@babel/plugin-syntax-nullish-coalescing-operator",
+      url: "https://git.io/vb4yx",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-nullish-coalescing-operator",
+      url: "https://git.io/vb4Se",
+    },
+  },
+  numericSeparator: {
+    syntax: {
+      name: "@babel/plugin-syntax-numeric-separator",
+      url: "https://git.io/vb4Sq",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-numeric-separator",
+      url: "https://git.io/vb4yS",
+    },
+  },
+  objectRestSpread: {
+    syntax: {
+      name: "@babel/plugin-syntax-object-rest-spread",
+      url: "https://git.io/vb4y5",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-object-rest-spread",
+      url: "https://git.io/vb4Ss",
+    },
+  },
+  optionalCatchBinding: {
+    syntax: {
+      name: "@babel/plugin-syntax-optional-catch-binding",
+      url: "https://git.io/vb4Sn",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-optional-catch-binding",
+      url: "https://git.io/vb4SI",
+    },
+  },
+  optionalChaining: {
+    syntax: {
+      name: "@babel/plugin-syntax-optional-chaining",
+      url: "https://git.io/vb4Sc",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-optional-chaining",
+      url: "https://git.io/vb4Sk",
+    },
+  },
+  pipelineOperator: {
+    syntax: {
+      name: "@babel/plugin-syntax-pipeline-operator",
+      url: "https://git.io/vb4yj",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-pipeline-operator",
+      url: "https://git.io/vb4SU",
+    },
+  },
+  throwExpressions: {
+    syntax: {
+      name: "@babel/plugin-syntax-throw-expressions",
+      url: "https://git.io/vb4SJ",
+    },
+    transform: {
+      name: "@babel/plugin-proposal-throw-expressions",
+      url: "https://git.io/vb4yF",
+    },
+  },
+  typescript: {
+    syntax: {
+      name: "@babel/plugin-syntax-typescript",
+      url: "https://git.io/vb4SC",
+    },
+    transform: {
+      name: "@babel/plugin-transform-typescript",
+      url: "https://git.io/vb4Sm",
+    },
+  },
+};
+
+const getNameURLCombination = ({ name, url }) => `${name} (${url})`;
+
+/*
+Returns a string of the format:
+Support for the experimental syntax [babylon plugin name] isn't currently enabled ([loc]):
+
+[code frame]
+
+Add [npm package name] ([url]) to the 'plugins' section of your Babel config
+to enable [parsing|transformation].
+*/
+export default function generateMissingPluginMessage(
+  missingPluginName: string,
+  loc: { line: number, column: number },
+  codeFrame: string,
+): string {
+  let helpMessage =
+    `Support for the experimental syntax '${missingPluginName}' isn't currently enabled ` +
+    `(${loc.line}:${loc.column + 1}):\n\n` +
+    codeFrame;
+  const pluginInfo = pluginNameMap[missingPluginName];
+  if (pluginInfo) {
+    const { syntax: syntaxPlugin, transform: transformPlugin } = pluginInfo;
+    if (syntaxPlugin) {
+      if (transformPlugin) {
+        const transformPluginInfo = getNameURLCombination(transformPlugin);
+        helpMessage +=
+          `\n\nAdd ${transformPluginInfo} to the 'plugins' section of your Babel config ` +
+          `to enable transformation.`;
+      } else {
+        const syntaxPluginInfo = getNameURLCombination(syntaxPlugin);
+        helpMessage +=
+          `\n\nAdd ${syntaxPluginInfo} to the 'plugins' section of your Babel config ` +
+          `to enable parsing.`;
+      }
+    }
+  }
+  return helpMessage;
+}

packages/babel-core/test/api.js

@@ -118,26 +118,33 @@ describe("api", function() {
   });
 
   it("transformFile", function(done) {
-    babel.transformFile(
-      __dirname + "/fixtures/api/file.js",
-      {
-        babelrc: false,
-      },
-      function(err, res) {
-        if (err) return done(err);
-        assert.equal(res.code, "foo();");
-        done();
-      },
-    );
+    const options = {
+      babelrc: false,
+    };
+    Object.freeze(options);
+    babel.transformFile(__dirname + "/fixtures/api/file.js", options, function(
+      err,
+      res,
+    ) {
+      if (err) return done(err);
+      assert.equal(res.code, "foo();");
+      // keep user options untouched
+      assert.deepEqual(options, { babelrc: false });
+      done();
+    });
   });
 
   it("transformFileSync", function() {
+    const options = {
+      babelrc: false,
+    };
+    Object.freeze(options);
     assert.equal(
-      babel.transformFileSync(__dirname + "/fixtures/api/file.js", {
-        babelrc: false,
-      }).code,
+      babel.transformFileSync(__dirname + "/fixtures/api/file.js", options)
+        .code,
       "foo();",
     );
+    assert.deepEqual(options, { babelrc: false });
   });
 
   it("options throw on falsy true", function() {
@@ -296,12 +303,6 @@ describe("api", function() {
         development: {
           passPerPreset: true,
           presets: [pushPreset("argthree"), pushPreset("argfour")],
-          env: {
-            development: {
-              passPerPreset: true,
-              presets: [pushPreset("argfive"), pushPreset("argsix")],
-            },
-          },
         },
       },
     });
@@ -309,32 +310,30 @@ describe("api", function() {
     assert.equal(
       result.code,
       [
-        "argtwo;",
-        "argone;",
-        "eleven;",
-        "twelve;",
+        "thirteen;",
+        "fourteen;",
+        "seventeen;",
+        "eighteen;",
         "one;",
         "two;",
+        "eleven;",
+        "twelve;",
+        "argtwo;",
+        "argone;",
         "five;",
         "six;",
         "three;",
         "four;",
-        "seventeen;",
-        "eighteen;",
         "nineteen;",
         "twenty;",
-        "thirteen;",
-        "fourteen;",
         "fifteen;",
         "sixteen;",
-        "argfive;",
-        "argsix;",
-        "argthree;",
-        "argfour;",
         "seven;",
         "eight;",
         "nine;",
         "ten;",
+        "argthree;",
+        "argfour;",
       ].join("\n"),
     );
   });
@@ -600,4 +599,52 @@ describe("api", function() {
       assert.ok(script.indexOf("typeof") >= 0);
     });
   });
+
+  describe("handle parsing errors", function() {
+    const options = {
+      babelrc: false,
+    };
+
+    it("only syntax plugin available", function(done) {
+      babel.transformFile(
+        __dirname + "/fixtures/api/parsing-errors/only-syntax/file.js",
+        options,
+        function(err) {
+          assert.ok(
+            RegExp(
+              "Support for the experimental syntax 'dynamicImport' isn't currently enabled \\(1:9\\):",
+            ).exec(err.message),
+          );
+          assert.ok(
+            RegExp(
+              "Add @babel/plugin-syntax-dynamic-import \\(https://git.io/vb4Sv\\) to the " +
+                "'plugins' section of your Babel config to enable parsing.",
+            ).exec(err.message),
+          );
+          done();
+        },
+      );
+    });
+
+    it("both syntax and transform plugin available", function(done) {
+      babel.transformFile(
+        __dirname + "/fixtures/api/parsing-errors/syntax-and-transform/file.js",
+        options,
+        function(err) {
+          assert.ok(
+            RegExp(
+              "Support for the experimental syntax 'asyncGenerators' isn't currently enabled \\(1:15\\):",
+            ).exec(err.message),
+          );
+          assert.ok(
+            RegExp(
+              "Add @babel/plugin-proposal-async-generator-functions \\(https://git.io/vb4yp\\) to the " +
+                "'plugins' section of your Babel config to enable transformation.",
+            ).exec(err.message),
+          );
+          done();
+        },
+      );
+    });
+  });
 });

packages/babel-core/test/caching-api.js

@@ -19,23 +19,6 @@ describe("caching API", () => {
     assert.notEqual(fn("one"), fn("two"));
   });
 
-  it("should allow permacaching with cache(true)", () => {
-    let count = 0;
-
-    const fn = makeStrongCache((arg, cache) => {
-      cache(true);
-      return { arg, count: count++ };
-    });
-
-    assert.deepEqual(fn("one"), { arg: "one", count: 0 });
-    assert.equal(fn("one"), fn("one"));
-
-    assert.deepEqual(fn("two"), { arg: "two", count: 1 });
-    assert.equal(fn("two"), fn("two"));
-
-    assert.notEqual(fn("one"), fn("two"));
-  });
-
   it("should allow disabling caching with .never()", () => {
     let count = 0;
 
@@ -55,25 +38,6 @@ describe("caching API", () => {
     assert.notEqual(fn("one"), fn("two"));
   });
 
-  it("should allow disabling caching with cache(false)", () => {
-    let count = 0;
-
-    const fn = makeStrongCache((arg, cache) => {
-      cache(false);
-      return { arg, count: count++ };
-    });
-
-    assert.deepEqual(fn("one"), { arg: "one", count: 0 });
-    assert.deepEqual(fn("one"), { arg: "one", count: 1 });
-    assert.notEqual(fn("one"), fn("one"));
-
-    assert.deepEqual(fn("two"), { arg: "two", count: 4 });
-    assert.deepEqual(fn("two"), { arg: "two", count: 5 });
-    assert.notEqual(fn("two"), fn("two"));
-
-    assert.notEqual(fn("one"), fn("two"));
-  });
-
   it("should allow caching based on a value with .using(fn)", () => {
     let count = 0;
     let other = "default";
@@ -115,47 +79,6 @@ describe("caching API", () => {
     assert.equal(fn("two"), fn("two"));
   });
 
-  it("should allow caching based on a value with cache(fn)", () => {
-    let count = 0;
-    let other = "default";
-
-    const fn = makeStrongCache((arg, cache) => {
-      const val = cache(() => other);
-
-      return { arg, val, count: count++ };
-    });
-
-    assert.deepEqual(fn("one"), { arg: "one", val: "default", count: 0 });
-    assert.equal(fn("one"), fn("one"));
-
-    assert.deepEqual(fn("two"), { arg: "two", val: "default", count: 1 });
-    assert.equal(fn("two"), fn("two"));
-
-    other = "new";
-
-    assert.deepEqual(fn("one"), { arg: "one", val: "new", count: 2 });
-    assert.equal(fn("one"), fn("one"));
-
-    assert.deepEqual(fn("two"), { arg: "two", val: "new", count: 3 });
-    assert.equal(fn("two"), fn("two"));
-
-    other = "default";
-
-    assert.deepEqual(fn("one"), { arg: "one", val: "default", count: 0 });
-    assert.equal(fn("one"), fn("one"));
-
-    assert.deepEqual(fn("two"), { arg: "two", val: "default", count: 1 });
-    assert.equal(fn("two"), fn("two"));
-
-    other = "new";
-
-    assert.deepEqual(fn("one"), { arg: "one", val: "new", count: 2 });
-    assert.equal(fn("one"), fn("one"));
-
-    assert.deepEqual(fn("two"), { arg: "two", val: "new", count: 3 });
-    assert.equal(fn("two"), fn("two"));
-  });
-
   it("should allow invalidation based on a value with .invalidate(fn)", () => {
     let count = 0;
     let other = "default";
@@ -298,12 +221,6 @@ describe("caching API", () => {
     assert.equal(fn("two"), fn("two"));
   });
 
-  it("should throw if caching is never configured and not defaulting", () => {
-    const fn = makeStrongCache(() => {}, false /* autoPermacache */);
-
-    assert.throws(() => fn(), /Error: Caching was left unconfigured./);
-  });
-
   it("should auto-permacache by default", () => {
     let count = 0;
 
@@ -410,4 +327,89 @@ describe("caching API", () => {
       /Cannot change caching after evaluation/,
     );
   });
+
+  describe("simple", () => {
+    it("should allow permacaching with cache(true)", () => {
+      let count = 0;
+
+      const fn = makeStrongCache((arg, cache) => {
+        cache = cache.simple();
+
+        cache(true);
+        return { arg, count: count++ };
+      });
+
+      assert.deepEqual(fn("one"), { arg: "one", count: 0 });
+      assert.equal(fn("one"), fn("one"));
+
+      assert.deepEqual(fn("two"), { arg: "two", count: 1 });
+      assert.equal(fn("two"), fn("two"));
+
+      assert.notEqual(fn("one"), fn("two"));
+    });
+
+    it("should allow disabling caching with cache(false)", () => {
+      let count = 0;
+
+      const fn = makeStrongCache((arg, cache) => {
+        cache = cache.simple();
+
+        cache(false);
+        return { arg, count: count++ };
+      });
+
+      assert.deepEqual(fn("one"), { arg: "one", count: 0 });
+      assert.deepEqual(fn("one"), { arg: "one", count: 1 });
+      assert.notEqual(fn("one"), fn("one"));
+
+      assert.deepEqual(fn("two"), { arg: "two", count: 4 });
+      assert.deepEqual(fn("two"), { arg: "two", count: 5 });
+      assert.notEqual(fn("two"), fn("two"));
+
+      assert.notEqual(fn("one"), fn("two"));
+    });
+
+    it("should allow caching based on a value with cache(fn)", () => {
+      let count = 0;
+      let other = "default";
+
+      const fn = makeStrongCache((arg, cache) => {
+        cache = cache.simple();
+
+        const val = cache(() => other);
+
+        return { arg, val, count: count++ };
+      });
+
+      assert.deepEqual(fn("one"), { arg: "one", val: "default", count: 0 });
+      assert.equal(fn("one"), fn("one"));
+
+      assert.deepEqual(fn("two"), { arg: "two", val: "default", count: 1 });
+      assert.equal(fn("two"), fn("two"));
+
+      other = "new";
+
+      assert.deepEqual(fn("one"), { arg: "one", val: "new", count: 2 });
+      assert.equal(fn("one"), fn("one"));
+
+      assert.deepEqual(fn("two"), { arg: "two", val: "new", count: 3 });
+      assert.equal(fn("two"), fn("two"));
+
+      other = "default";
+
+      assert.deepEqual(fn("one"), { arg: "one", val: "default", count: 0 });
+      assert.equal(fn("one"), fn("one"));
+
+      assert.deepEqual(fn("two"), { arg: "two", val: "default", count: 1 });
+      assert.equal(fn("two"), fn("two"));
+
+      other = "new";
+
+      assert.deepEqual(fn("one"), { arg: "one", val: "new", count: 2 });
+      assert.equal(fn("one"), fn("one"));
+
+      assert.deepEqual(fn("two"), { arg: "two", val: "new", count: 3 });
+      assert.equal(fn("two"), fn("two"));
+    });
+  });
 });

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

@@ -42,10 +42,10 @@ describe("@babel/core config loading", () => {
 
       const options1 = loadConfig(opts).options;
       expect(options1.plugins.map(p => p.key)).to.eql([
-        "plugin6",
-        "plugin5",
         "plugin1",
         "plugin2",
+        "plugin6",
+        "plugin5",
         "plugin4",
         "plugin3",
       ]);
@@ -86,7 +86,7 @@ describe("@babel/core config loading", () => {
       expect(options2.plugins.length).to.equal(options1.plugins.length);
 
       for (let i = 0; i < options1.plugins.length; i++) {
-        if (i === 2) {
+        if (i === 0) {
           expect(options2.plugins[i]).not.to.equal(options1.plugins[i]);
         } else {
           expect(options2.plugins[i]).to.equal(options1.plugins[i]);
@@ -99,7 +99,7 @@ describe("@babel/core config loading", () => {
       expect(options3.plugins.length).to.equal(options1.plugins.length);
 
       for (let i = 0; i < options1.plugins.length; i++) {
-        if (i === 2 || i === 5) {
+        if (i === 0 || i === 5) {
           expect(options3.plugins[i]).not.to.equal(options1.plugins[i]);
         } else {
           expect(options3.plugins[i]).to.equal(options1.plugins[i]);
@@ -150,7 +150,7 @@ describe("@babel/core config loading", () => {
       expect(options2.plugins.length).to.equal(options1.plugins.length);
 
       for (let i = 0; i < options1.plugins.length; i++) {
-        if (i === 2 || i === 3 || i === 4 || i === 5 || i === 6) {
+        if (i === 0 || i === 1 || i === 4 || i === 5 || i === 6) {
           expect(options2.plugins[i]).not.to.equal(options1.plugins[i]);
         } else {
           expect(options2.plugins[i]).to.equal(options1.plugins[i]);
@@ -185,7 +185,7 @@ describe("@babel/core config loading", () => {
       expect(options2.plugins.length).to.equal(options1.plugins.length);
 
       for (let i = 0; i < options2.plugins.length; i++) {
-        if (i === 0) {
+        if (i === 2) {
           expect(options2.plugins[i]).not.to.equal(options1.plugins[i]);
         } else {
           expect(options2.plugins[i]).to.equal(options1.plugins[i]);
@@ -205,7 +205,7 @@ describe("@babel/core config loading", () => {
       expect(options2.plugins.length).to.equal(options1.plugins.length);
 
       for (let i = 0; i < options2.plugins.length; i++) {
-        if (i === 1) {
+        if (i === 3) {
           expect(options2.plugins[i]).not.to.equal(options1.plugins[i]);
         } else {
           expect(options2.plugins[i]).to.equal(options1.plugins[i]);
@@ -224,7 +224,7 @@ describe("@babel/core config loading", () => {
       expect(options2.plugins.length).to.equal(options1.plugins.length);
 
       for (let i = 0; i < options1.plugins.length; i++) {
-        if (i === 0) {
+        if (i === 2) {
           expect(options2.plugins[i]).not.to.equal(options1.plugins[i]);
         } else {
           expect(options2.plugins[i]).to.equal(options1.plugins[i]);
@@ -243,7 +243,7 @@ describe("@babel/core config loading", () => {
       expect(options2.plugins.length).to.equal(options1.plugins.length);
 
       for (let i = 0; i < options1.plugins.length; i++) {
-        if (i === 1) {
+        if (i === 3) {
           expect(options2.plugins[i]).not.to.equal(options1.plugins[i]);
         } else {
           expect(options2.plugins[i]).to.equal(options1.plugins[i]);

packages/babel-core/test/fixtures/api/parsing-errors/only-syntax/file.js

@@ -0,0 +1 @@
+var $ = import("jquery");

packages/babel-core/test/fixtures/api/parsing-errors/syntax-and-transform/file.js

@@ -0,0 +1,4 @@
+async function* agf() {
+  await 1;
+  yield 2;
+}

packages/babel-core/test/fixtures/config/.babelignore

@@ -1 +0,0 @@
-root-ignore

packages/babel-core/test/fixtures/config/.babelrc

@@ -1,4 +0,0 @@
-{
-  "plugins": ["root"],
-  "extends": "./extended.babelrc.json"
-}

packages/babel-core/test/fixtures/config/complex-plugin-config/.babelignore

@@ -18,4 +18,5 @@ seventeen.js
 eighteen.js
 nineteen.js
 twenty.js
-plugin.js
+
+**/plugin.js

packages/babel-core/test/fixtures/config/complex-plugin-config/config-identity/babelrc-js/.babelrc.js

@@ -2,6 +2,8 @@ module.exports = function(api) {
   api.env();
 
   return {
-    comments: false,
+    plugins: [
+      require("./plugin"),
+    ],
   };
 }

packages/babel-core/test/fixtures/config/complex-plugin-config/config-identity/babelrc-js/plugin.js

@@ -0,0 +1,3 @@
+module.exports = function() {
+  return {};
+};

packages/babel-core/test/fixtures/config/complex-plugin-config/config-identity/babelrc/.babelrc

@@ -1,3 +1,3 @@
 {
-  comments: false,
+  plugins: ["./plugin"],
 }

packages/babel-core/test/fixtures/config/complex-plugin-config/config-identity/babelrc/plugin.js

@@ -0,0 +1,3 @@
+module.exports = function() {
+  return {};
+};

packages/babel-core/test/fixtures/config/complex-plugin-config/config-identity/pkg/package.json

@@ -1,5 +1,5 @@
 {
   "babel": {
-    "comments": false
+    "plugins": ["./plugin"]
   }
 }

packages/babel-core/test/fixtures/config/complex-plugin-config/config-identity/pkg/plugin.js

@@ -0,0 +1,3 @@
+module.exports = function() {
+  return {};
+};

packages/babel-core/test/fixtures/config/config-files/.babelignore

@@ -0,0 +1 @@
+# Placeholder so the monorepo ignore isn't accessed

packages/babel-core/test/fixtures/config/config-files/babelignore/.babelignore

@@ -0,0 +1 @@
+src.js

packages/babel-core/test/fixtures/config/config-files/babelrc-error/.babelrc

@@ -0,0 +1 @@
+{45

packages/babel-core/test/fixtures/config/config-files/babelrc-js-error/.babelrc.js

@@ -0,0 +1,3 @@
+module.exports = function() {
+  throw new Error("Babelrc threw an error");
+};

packages/babel-core/test/fixtures/config/config-files/babelrc-js/.babelrc.js

@@ -0,0 +1,3 @@
+module.exports = {
+  comments: true,
+};

packages/babel-core/test/fixtures/config/config-files/babelrc/.babelrc

@@ -0,0 +1,3 @@
+{
+  comments: true,
+}

packages/babel-core/test/fixtures/config/config-files/both-babelrc/.babelrc.js

@@ -0,0 +1 @@
+module.exports = {};

packages/babel-core/test/fixtures/config/config-files/pkg-babelrc-js/.babelrc.js

@@ -0,0 +1 @@
+module.exports = {};

packages/babel-core/test/fixtures/config/config-files/pkg-babelrc/.babelrc

@@ -0,0 +1 @@
+{}

packages/babel-core/test/fixtures/config/config-files/pkg-error/package.json

@@ -0,0 +1,3 @@
+{
+  "babel": {235
+}

packages/babel-core/test/fixtures/config/config-files/pkg-ignored/.babelrc

@@ -0,0 +1,3 @@
+{
+  comments: true,
+}

packages/babel-core/test/fixtures/config/config-files/pkg-ignored/package.json

@@ -0,0 +1 @@
+{}

packages/babel-core/test/fixtures/config/config-files/pkg/package.json

@@ -0,0 +1,5 @@
+{
+  "babel": {
+    "comments": true
+  }
+}

packages/babel-core/test/fixtures/config/dir1/src.js

@@ -1 +0,0 @@
-// empty

packages/babel-core/test/fixtures/config/dir2/.babelrc

@@ -1,5 +0,0 @@
-{
-  "plugins": [
-    "dir2"
-  ]
-}

packages/babel-core/test/fixtures/config/dir2/src.js

@@ -1 +0,0 @@
-// empty

packages/babel-core/test/fixtures/config/dir3/package.json

@@ -1,5 +0,0 @@
-
-{
-  "name": "application-name",
-  "version": "0.0.1"
-}

packages/babel-core/test/fixtures/config/dir3/src.js

@@ -1 +0,0 @@
-// empty

packages/babel-core/test/fixtures/config/env/.babelrc

@@ -1,11 +0,0 @@
-{
-  "plugins": ["env-base"],
-  "env": {
-    "foo": {
-      "plugins": ["env-foo"]
-    },
-    "bar": {
-      "plugins": ["env-bar"]
-    }
-  }
-}

packages/babel-core/test/fixtures/config/env/src.js

@@ -1 +0,0 @@
-// empty

packages/babel-core/test/fixtures/config/extended.babelrc.json

@@ -1,5 +0,0 @@
-{
-  "plugins": [
-    "extended"
-  ]
-}

packages/babel-core/test/fixtures/config/ignore-negate-folder/.babelrc

@@ -1,6 +0,0 @@
-{
-  ignore: [
-    "*",
-    "!folder",
-  ],
-}

packages/babel-core/test/fixtures/config/ignore-negate-folder/folder/.gitignore

@@ -1,2 +0,0 @@
-# Blank .gitignore to ensure this directory exists.
-!.gitignore