v7.0.0-alpha.19

* gulp-babel 7.0

.babelrc.js

@@ -6,12 +6,28 @@ let envOpts = {
 
 module.exports = {
   comments: false,
+  plugins: [
+    // temp until next release
+    function() {
+      return {
+        visitor: {
+          "Function": function(path) {
+            const node = path.node;
+            for (let i = 0; i < node.params.length; i++) {
+              const param = node.params[i];
+              if (param.type === "AssignmentPattern") {
+                param.left.optional = false;
+              }
+            }
+          }
+        }
+      };
+    }
+  ],
   presets: [
-    [
-      "env", envOpts
-    ],
+    ["env", envOpts],
     "stage-0",
-    "flow",
+    "flow"
   ],
   env: {
     cov: {
@@ -21,9 +37,9 @@ module.exports = {
   }
 };
 
-if (process.env.BABEL_ENV === 'development') {
+if (process.env.BABEL_ENV === "development") {
   envOpts.targets = {
     node: "current"
   };
   envOpts.debug = true;
-};
+}

.eslintrc

@@ -1,11 +1,11 @@
 {
   "extends": "babel",
+  "plugins": [
+    "prettier"
+  ],
   "rules": {
-    "comma-dangle": ["error", "always-multiline"],
     "curly": ["error", "multi-line"],
-    "func-call-spacing": "error",
-    "key-spacing": "error",
-    "no-multi-spaces": "error"
+    "prettier/prettier": ["error", { "trailingComma": "es5" }]
   },
   "env": {
     "node": true,

.flowconfig

@@ -13,6 +13,5 @@ lib/types.js
 lib/third-party-libs.js.flow
 
 [options]
-strip_root=true
 suppress_comment= \\(.\\|\n\\)*\\$FlowFixMe
 suppress_comment= \\(.\\|\n\\)*\\$FlowIssue

.gitignore

@@ -10,6 +10,7 @@
 /coverage
 dist
 /.package.json
+package-lock.json
 /packages/babel-runtime/core-js/**/*.js
 !/packages/babel-runtime/core-js/map.js
 /packages/babel-runtime/helpers/*.js
@@ -21,6 +22,8 @@ dist
 /packages/babel-runtime/helpers/es6/*.js
 !/packages/babel-runtime/helpers/es6/toArray.js
 /packages/babel-register/test/.babel
+/packages/babel-cli/test/tmp
+/packages/babel-node/test/tmp
 /packages/*/lib
 .nyc_output
 /babel.sublime-workspace

.travis.yml

@@ -7,12 +7,17 @@ cache:
   directories:
   - node_modules
 node_js:
-  - '7'
+  - '8'
   - '6'
   - '4'
 
 env:
-  - JOB=test
+  global:
+    - PATH=$HOME/.yarn/bin:$PATH
+    - JOB=test
+
+before_install:
+  - curl -o- -L https://yarnpkg.com/install.sh | bash -s -- --version 0.28.1
 
 script:
   - 'if [ "$JOB" = "test" ]; then make test-ci; fi'

.yarnrc

@@ -0,0 +1 @@
+workspaces-experimental true

CONTRIBUTING.md

@@ -40,7 +40,7 @@ Feel free to check out the `#discussion`/`#development` channels on our [Slack](
 
 **Note:** Versions `< 5.1.10` can't be built.
 
-Babel is built for Node.js 4 and up but we develop using Node.js 6. Make sure you are on npm 3.
+Babel is built for Node.js 4 and up but we develop using Node.js 6/8 and yarn.
 
 You can check this with `node -v` and `npm -v`.
 
@@ -120,6 +120,12 @@ Use the `TEST_GREP` variable to run a subset of tests by name:
 $ TEST_GREP=transformation make test
 ```
 
+Substitute spaces for hyphens and forward slashes when targeting specific test names:
+
+```sh
+$ TEST_GREP="arrow functions destructuring parameters" make test
+```
+
 To enable the Node.js debugger added in v6.3.0, set the `TEST_DEBUG` environment variable:
 
 ```sh

Gulpfile.js

@@ -21,32 +21,41 @@ function swapSrcWithLib(srcPath) {
 
 gulp.task("default", ["build"]);
 
-gulp.task("build", function () {
-  return gulp.src(scripts, { base: base })
-    .pipe(plumber({
-      errorHandler: function (err) {
-        gutil.log(err.stack);
-      },
-    }))
-    .pipe(newer({
-      dest: base,
-      map: swapSrcWithLib,
-    }))
-    .pipe(through.obj(function (file, enc, callback) {
-      gutil.log("Compiling", "'" + chalk.cyan(file.relative) + "'...");
-      callback(null, file);
-    }))
+gulp.task("build", function() {
+  return gulp
+    .src(scripts, { base: base })
+    .pipe(
+      plumber({
+        errorHandler: function(err) {
+          gutil.log(err.stack);
+        },
+      })
+    )
+    .pipe(
+      newer({
+        dest: base,
+        map: swapSrcWithLib,
+      })
+    )
+    .pipe(
+      through.obj(function(file, enc, callback) {
+        gutil.log("Compiling", "'" + chalk.cyan(file.relative) + "'...");
+        callback(null, file);
+      })
+    )
     .pipe(babel())
-    .pipe(through.obj(function (file, enc, callback) {
-      // Passing 'file.relative' because newer() above uses a relative path and this keeps it consistent.
-      file.path = path.resolve(file.base, swapSrcWithLib(file.relative));
-      callback(null, file);
-    }))
+    .pipe(
+      through.obj(function(file, enc, callback) {
+        // Passing 'file.relative' because newer() above uses a relative path and this keeps it consistent.
+        file.path = path.resolve(file.base, swapSrcWithLib(file.relative));
+        callback(null, file);
+      })
+    )
     .pipe(gulp.dest(base));
 });
 
-gulp.task("watch", ["build"], function () {
-  watch(scripts, { debounceDelay: 200 }, function () {
+gulp.task("watch", ["build"], function() {
+  watch(scripts, { debounceDelay: 200 }, function() {
     gulp.start("build");
   });
 });

Makefile

@@ -2,9 +2,13 @@ MAKEFLAGS = -j1
 
 export NODE_ENV = test
 
+# Fix color output until TravisCI fixes https://github.com/travis-ci/travis-ci/issues/7967
+export FORCE_COLOR = true
+
 .PHONY: build build-dist watch lint fix clean test-clean test-only test test-ci publish bootstrap
 
 build: clean
+	rm -rf packages/*/lib
 	./node_modules/.bin/gulp build
 
 build-dist: build
@@ -22,7 +26,7 @@ lint:
 	./node_modules/.bin/eslint scripts packages *.js --format=codeframe
 
 flow:
-	./node_modules/.bin/flow check
+	./node_modules/.bin/flow check --strip-root
 
 fix:
 	./node_modules/.bin/eslint scripts packages *.js --format=codeframe --fix
@@ -43,6 +47,8 @@ clean-all:
 	rm -rf packages/*/lib
 	rm -rf node_modules
 	rm -rf packages/*/node_modules
+	rm -rf package-lock.json
+	rm -rf packages/*/package-lock.json
 	make clean
 
 test-only:
@@ -55,10 +61,11 @@ test-ci:
 	make bootstrap
 	make test-only
 
+test-ci-coverage: SHELL:=/bin/bash
 test-ci-coverage:
 	BABEL_ENV=cov make bootstrap
 	./scripts/test-cov.sh
-	./node_modules/.bin/codecov -f coverage/coverage-final.json
+	bash <(curl -s https://codecov.io/bash) -f coverage/coverage-final.json
 
 publish:
 	git pull --rebase

README.md

@@ -86,6 +86,7 @@ Check out our [CONTRIBUTING.md](https://github.com/babel/babel/blob/master/CONTR
 You can also start by checking out the issues with the [help-wanted](https://github.com/babel/babel/issues?q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22) label.
 
 Our discussions/notes/roadmap: [babel/notes](https://github.com/babel/notes)
+Our progress on TC39 proposals: [babel/proposals](https://github.com/babel/proposals)
 
 ## Packages
 

circle.yml

@@ -1,7 +1,7 @@
 machine:
   node:
     version:
-      6
+      8
 
 dependencies:
   pre:

doc/design/monorepo.md

@@ -21,7 +21,6 @@ This is quite taboo but let's look at the pros and cons:
 
  * Codebase looks more intimidating.
  * Repo is bigger in size.
- * Lower ranking in [npms](https://npms.io/) results. At least until [npms-io/npms-analyzer#83](https://github.com/npms-io/npms-analyzer/issues/83) is fixed.
  * ???
 
 ## This is dumb! Nobody in open source does this!

lerna.json

@@ -1,8 +1,7 @@
 {
   "lerna": "2.0.0-rc.4",
-  "version": "7.0.0-alpha.12",
+  "version": "7.0.0-alpha.19",
   "changelog": {
-    "repo": "babel/babel",
     "labels": {
       "tag: spec compliancy": ":eyeglasses: Spec Compliancy",
       "tag: breaking change": ":boom: Breaking Change",
@@ -21,5 +20,10 @@
         "test/**"
       ]
     }
-  }
+  },
+  "packages": [
+    "packages/*"
+  ],
+  "npmClient": "yarn",
+  "useWorkspaces": true
 }

package.json

@@ -3,51 +3,55 @@
   "private": true,
   "license": "MIT",
   "scripts": {
-    "test": "make test",
     "build": "make build",
+    "fix": "make fix",
     "lint": "make lint",
-    "fix": "make fix"
+    "precommit": "lint-staged",
+    "test": "make test"
   },
   "devDependencies": {
     "async": "^1.5.0",
-    "babel-cli": "7.0.0-alpha.9",
-    "babel-core": "7.0.0-alpha.9",
-    "babel-eslint": "^7.0.0",
-    "babel-plugin-istanbul": "^2.0.1",
-    "babel-preset-env": "2.0.0-alpha.7",
-    "babel-preset-flow": "7.0.0-alpha.9",
-    "babel-preset-stage-0": "7.0.0-alpha.9",
-    "babel-register": "7.0.0-alpha.9",
+    "babel-cli": "7.0.0-alpha.15",
+    "babel-core": "7.0.0-alpha.15",
+    "babel-eslint": "8.0.0-alpha.15",
+    "babel-plugin-istanbul": "^4.1.4",
+    "babel-preset-env": "2.0.0-alpha.15",
+    "babel-preset-flow": "7.0.0-alpha.15",
+    "babel-preset-stage-0": "7.0.0-alpha.15",
+    "babel-register": "7.0.0-alpha.15",
     "browserify": "^13.1.1",
     "bundle-collapser": "^1.2.1",
-    "chai": "^3.5.0",
-    "chalk": "1.1.1",
-    "codecov": "^1.0.1",
+    "chai": "^4.1.0",
+    "chalk": "^2.0.0",
     "derequire": "^2.0.2",
-    "eslint": "^3.9.0",
-    "eslint-config-babel": "^6.0.0",
+    "eslint": "^3.14.1",
+    "eslint-config-babel": "^7.0.1",
     "eslint-plugin-flowtype": "^2.20.0",
-    "flow-bin": "^0.41.0",
+    "eslint-plugin-prettier": "^2.1.2",
+    "flow-bin": "^0.52.0",
     "gulp": "^3.9.0",
-    "gulp-babel": "babel/gulp-babel#b7-alpha",
+    "gulp-babel": "^7.0.0",
     "gulp-newer": "^1.0.0",
     "gulp-plumber": "^1.0.1",
     "gulp-util": "^3.0.7",
     "gulp-watch": "^4.3.5",
-    "lerna": "2.0.0-rc.4",
-    "lerna-changelog": "^0.2.0",
+    "husky": "^0.13.2",
+    "lerna": "2.0.0",
+    "lerna-changelog": "^0.6.0",
+    "lint-staged": "^3.6.1",
     "lodash": "^4.2.0",
     "mocha": "^3.0.0",
-    "nyc": "^10.0.0",
-    "output-file-sync": "^1.1.1",
+    "nyc": "^11.0.3",
+    "output-file-sync": "^2.0.0",
+    "prettier": "^1.5.0",
     "rimraf": "^2.4.3",
     "semver": "^5.0.0",
     "through2": "^2.0.0",
     "uglify-js": "^2.4.16"
   },
-  "devEngines": {
-    "node": ">= 4.x <= 7.x",
-    "npm": "2.x || 3.x || 4.x"
+  "engines": {
+    "node": ">= 4.x <= 8.x",
+    "npm": ">= 2.x <= 5.x"
   },
   "nyc": {
     "all": true,
@@ -57,5 +61,14 @@
     ],
     "sourceMap": false,
     "instrument": false
-  }
+  },
+  "lint-staged": {
+    "*.js": [
+      "eslint --format=codeframe --fix",
+      "git add"
+    ]
+  },
+  "workspaces": [
+    "packages/*"
+  ]
 }

packages/.eslintrc

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

packages/babel-cli/package.json

@@ -1,6 +1,6 @@
 {
   "name": "babel-cli",
-  "version": "7.0.0-alpha.12",
+  "version": "7.0.0-alpha.19",
   "description": "Babel command line.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -16,24 +16,24 @@
     "compiler"
   ],
   "dependencies": {
-    "babel-core": "7.0.0-alpha.12",
-    "babel-polyfill": "7.0.0-alpha.12",
-    "babel-register": "7.0.0-alpha.12",
+    "babel-core": "7.0.0-alpha.19",
+    "babel-polyfill": "7.0.0-alpha.19",
+    "babel-register": "7.0.0-alpha.19",
     "commander": "^2.8.1",
     "convert-source-map": "^1.1.0",
     "fs-readdir-recursive": "^1.0.0",
     "glob": "^7.0.0",
     "lodash": "^4.2.0",
-    "output-file-sync": "^1.1.0",
+    "output-file-sync": "^2.0.0",
     "slash": "^1.0.0",
     "source-map": "^0.5.0",
-    "v8flags": "^2.0.10"
+    "v8flags": "^3.0.0"
   },
   "optionalDependencies": {
     "chokidar": "^1.6.1"
   },
   "devDependencies": {
-    "babel-helper-fixtures": "7.0.0-alpha.12"
+    "babel-helper-fixtures": "7.0.0-alpha.19"
   },
   "bin": {
     "babel-doctor": "./bin/babel-doctor.js",

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

@@ -24,9 +24,21 @@ function collect(value, previousValue): Array<string> {
 /* eslint-disable max-len */
 program.option("-e, --eval [script]", "Evaluate script");
 program.option("-p, --print [code]", "Evaluate script and print result");
-program.option("-o, --only [globs]", "A comma-separated list of glob patterns to compile", collect);
-program.option("-i, --ignore [globs]", "A comma-separated list of glob patterns to skip compiling", collect);
-program.option("-x, --extensions [extensions]", "List of extensions to hook into [.es6,.js,.es,.jsx,.mjs]", collect);
+program.option(
+  "-o, --only [globs]",
+  "A comma-separated list of glob patterns to compile",
+  collect,
+);
+program.option(
+  "-i, --ignore [globs]",
+  "A comma-separated list of glob patterns to skip compiling",
+  collect,
+);
+program.option(
+  "-x, --extensions [extensions]",
+  "List of extensions to hook into [.es6,.js,.es,.jsx,.mjs]",
+  collect,
+);
 program.option("-w, --plugins [string]", "", collect);
 program.option("-b, --presets [string]", "", collect);
 /* eslint-enable max-len */
@@ -55,23 +67,28 @@ const replPlugin = ({ types: t }) => ({
 
     VariableDeclaration(path) {
       if (path.node.kind !== "var") {
-        throw path.buildCodeFrameError("Only `var` variables are supported in the REPL");
+        throw path.buildCodeFrameError(
+          "Only `var` variables are supported in the REPL",
+        );
       }
     },
 
     Program(path) {
-      if (path.get("body").some((child) => child.isExpressionStatement())) return;
+      if (path.get("body").some(child => child.isExpressionStatement())) return;
 
       // If the executed code doesn't evaluate to a value,
       // prevent implicit strict mode from printing 'use strict'.
-      path.pushContainer("body", t.expressionStatement(t.identifier("undefined")));
+      path.pushContainer(
+        "body",
+        t.expressionStatement(t.identifier("undefined")),
+      );
     },
   },
 });
 
 //
 
-const _eval = function (code, filename) {
+const _eval = function(code, filename) {
   code = code.trim();
   if (!code) return undefined;
 
@@ -113,7 +130,7 @@ if (program.eval || program.print) {
 
     let i = 0;
     let ignoreNext = false;
-    args.some(function (arg, i2) {
+    args.some(function(arg, i2) {
       if (ignoreNext) {
         ignoreNext = false;
         return;
@@ -133,7 +150,9 @@ if (program.eval || program.print) {
 
     // make the filename absolute
     const filename = args[0];
-    if (!path.isAbsolute(filename)) args[0] = path.join(process.cwd(), filename);
+    if (!path.isAbsolute(filename)) {
+      args[0] = path.join(process.cwd(), filename);
+    }
 
     // add back on node and concat the sliced args
     process.argv = ["node"].concat(args);

packages/babel-cli/src/babel-external-helpers.js

@@ -10,8 +10,16 @@ function collect(value, previousValue): Array<string> {
   return previousValue ? previousValue.concat(values) : values;
 }
 
-commander.option("-l, --whitelist [whitelist]", "Whitelist of helpers to ONLY include", collect);
-commander.option("-t, --output-type [type]", "Type of output (global|umd|var)", "global");
+commander.option(
+  "-l, --whitelist [whitelist]",
+  "Whitelist of helpers to ONLY include",
+  collect,
+);
+commander.option(
+  "-t, --output-type [type]",
+  "Type of output (global|umd|var)",
+  "global",
+);
 
 commander.usage("[options]");
 commander.parse(process.argv);

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

@@ -33,7 +33,7 @@ function getNormalizedV8Flag(arg) {
   return arg;
 }
 
-getV8Flags(function (err, v8Flags) {
+getV8Flags(function(err, v8Flags) {
   babelArgs.forEach(function(arg) {
     const flag = arg.split("=")[0];
 
@@ -59,7 +59,10 @@ getV8Flags(function (err, v8Flags) {
         break;
 
       default:
-        if (v8Flags.indexOf(getNormalizedV8Flag(flag)) >= 0 || arg.indexOf("--trace") === 0) {
+        if (
+          v8Flags.indexOf(getNormalizedV8Flag(flag)) >= 0 ||
+          arg.indexOf("--trace") === 0
+        ) {
           args.unshift(arg);
         } else {
           args.push(arg);
@@ -80,9 +83,11 @@ getV8Flags(function (err, v8Flags) {
     if (err.code !== "MODULE_NOT_FOUND") throw err;
 
     const child_process = require("child_process");
-    const proc = child_process.spawn(process.argv[0], args, { stdio: "inherit" });
-    proc.on("exit", function (code, signal) {
-      process.on("exit", function () {
+    const proc = child_process.spawn(process.argv[0], args, {
+      stdio: "inherit",
+    });
+    proc.on("exit", function(code, signal) {
+      process.on("exit", function() {
         if (signal) {
           process.kill(process.pid, signal);
         } else {
@@ -90,5 +95,10 @@ getV8Flags(function (err, v8Flags) {
         }
       });
     });
+
+    process.on("SIGINT", () => {
+      proc.kill("SIGINT");
+      process.exit(1);
+    });
   }
 });

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

@@ -6,19 +6,27 @@ import fs from "fs";
 
 import * as util from "./util";
 
-export default function (commander, filenames, opts) {
+export default function(commander, filenames, opts) {
   function write(src, relative) {
-    if (!util.isCompilableExtension(relative, commander.extensions)) return false;
+    if (!util.isCompilableExtension(relative, commander.extensions)) {
+      return false;
+    }
 
     // remove extension and then append back on .js
     relative = relative.replace(/\.(\w*?)$/, "") + ".js";
 
     const dest = path.join(commander.outDir, relative);
 
-    const data = util.compile(src, defaults({
-      sourceFileName: slash(path.relative(dest + "/..", src)),
-      sourceMapTarget: path.basename(relative),
-    }, opts));
+    const data = util.compile(
+      src,
+      defaults(
+        {
+          sourceFileName: slash(path.relative(dest + "/..", src)),
+          sourceMapTarget: path.basename(relative),
+        },
+        opts,
+      ),
+    );
 
     if (!data) return false;
 
@@ -55,7 +63,7 @@ export default function (commander, filenames, opts) {
     if (stat.isDirectory(filename)) {
       const dirname = filename;
 
-      util.readdir(dirname).forEach(function (filename) {
+      util.readdir(dirname).forEach(function(filename) {
         const src = path.join(dirname, filename);
         handleFile(src, filename);
       });
@@ -71,7 +79,7 @@ export default function (commander, filenames, opts) {
   if (commander.watch) {
     const chokidar = util.requireChokidar();
 
-    filenames.forEach(function (dirname) {
+    filenames.forEach(function(dirname) {
       const watcher = chokidar.watch(dirname, {
         persistent: true,
         ignoreInitial: true,
@@ -81,8 +89,8 @@ export default function (commander, filenames, opts) {
         },
       });
 
-      ["add", "change"].forEach(function (type) {
-        watcher.on(type, function (filename) {
+      ["add", "change"].forEach(function(type) {
+        watcher.on(type, function(filename) {
           const relative = path.relative(dirname, filename) || filename;
           try {
             handleFile(filename, relative);

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

@@ -7,14 +7,14 @@ import fs from "fs";
 
 import * as util from "./util";
 
-export default function (commander, filenames, opts) {
+export default function(commander, filenames, opts) {
   if (commander.sourceMaps === "inline") {
     opts.sourceMaps = true;
   }
 
   let results = [];
 
-  const buildResult = function () {
+  const buildResult = function() {
     const map = new sourceMap.SourceMapGenerator({
       file: path.basename(commander.outFile || "") || "stdout",
       sourceRoot: opts.sourceRoot,
@@ -23,14 +23,14 @@ export default function (commander, filenames, opts) {
     let code = "";
     let offset = 0;
 
-    results.forEach(function (result) {
+    results.forEach(function(result) {
       code += result.code + "\n";
 
       if (result.map) {
         const consumer = new sourceMap.SourceMapConsumer(result.map);
         const sources = new Set();
 
-        consumer.eachMapping(function (mapping) {
+        consumer.eachMapping(function(mapping) {
           if (mapping.source != null) sources.add(mapping.source);
 
           map.addMapping({
@@ -39,14 +39,17 @@ export default function (commander, filenames, opts) {
               column: mapping.generatedColumn,
             },
             source: mapping.source,
-            original: mapping.source == null ? null : {
-              line: mapping.originalLine,
-              column: mapping.originalColumn,
-            },
+            original:
+              mapping.source == null
+                ? null
+                : {
+                    line: mapping.originalLine,
+                    column: mapping.originalColumn,
+                  },
           });
         });
 
-        sources.forEach((source) => {
+        sources.forEach(source => {
           const content = consumer.sourceContentFor(source, true);
           if (content !== null) {
             map.setSourceContent(source, content);
@@ -59,7 +62,10 @@ export default function (commander, filenames, opts) {
 
     // add the inline sourcemap comment if we've either explicitly asked for inline source
     // maps, or we've requested them without any output file
-    if (commander.sourceMaps === "inline" || (!commander.outFile && commander.sourceMaps)) {
+    if (
+      commander.sourceMaps === "inline" ||
+      (!commander.outFile && commander.sourceMaps)
+    ) {
       code += "\n" + convertSourceMap.fromObject(map).toComment();
     }
 
@@ -69,7 +75,7 @@ export default function (commander, filenames, opts) {
     };
   };
 
-  const output = function () {
+  const output = function() {
     const result = buildResult();
 
     if (commander.outFile) {
@@ -86,36 +92,45 @@ export default function (commander, filenames, opts) {
     }
   };
 
-  const stdin = function () {
+  const stdin = function() {
     let code = "";
 
     process.stdin.setEncoding("utf8");
 
-    process.stdin.on("readable", function () {
+    process.stdin.on("readable", function() {
       const chunk = process.stdin.read();
       if (chunk !== null) code += chunk;
     });
 
-    process.stdin.on("end", function () {
-      results.push(util.transform(commander.filename, code, defaults({
-        sourceFileName: "stdin",
-      }, opts)));
+    process.stdin.on("end", function() {
+      results.push(
+        util.transform(
+          commander.filename,
+          code,
+          defaults(
+            {
+              sourceFileName: "stdin",
+            },
+            opts,
+          ),
+        ),
+      );
       output();
     });
   };
 
-  const walk = function () {
+  const walk = function() {
     const _filenames = [];
     results = [];
 
-    filenames.forEach(function (filename) {
+    filenames.forEach(function(filename) {
       if (!fs.existsSync(filename)) return;
 
       const stat = fs.statSync(filename);
       if (stat.isDirectory()) {
         const dirname = filename;
 
-        util.readdirFilter(filename).forEach(function (filename) {
+        util.readdirFilter(filename).forEach(function(filename) {
           _filenames.push(path.join(dirname, filename));
         });
       } else {
@@ -123,16 +138,25 @@ export default function (commander, filenames, opts) {
       }
     });
 
-    _filenames.forEach(function (filename) {
+    _filenames.forEach(function(filename) {
       let sourceFilename = filename;
       if (commander.outFile) {
-        sourceFilename = path.relative(path.dirname(commander.outFile), sourceFilename);
+        sourceFilename = path.relative(
+          path.dirname(commander.outFile),
+          sourceFilename,
+        );
       }
       sourceFilename = slash(sourceFilename);
 
-      const data = util.compile(filename, defaults({
-        sourceFileName: sourceFilename,
-      }, opts));
+      const data = util.compile(
+        filename,
+        defaults(
+          {
+            sourceFileName: sourceFilename,
+          },
+          opts,
+        ),
+      );
 
       if (!data) return;
 
@@ -142,33 +166,36 @@ export default function (commander, filenames, opts) {
     output();
   };
 
-  const files = function () {
-
+  const files = function() {
     if (!commander.skipInitialBuild) {
       walk();
     }
 
     if (commander.watch) {
       const chokidar = util.requireChokidar();
-      chokidar.watch(filenames, {
-        persistent: true,
-        ignoreInitial: true,
-        awaitWriteFinish: {
-          stabilityThreshold: 50,
-          pollInterval: 10,
-        },
-      }).on("all", function (type, filename) {
-        if (!util.isCompilableExtension(filename, commander.extensions)) return;
-
-        if (type === "add" || type === "change") {
-          util.log(type + " " + filename);
-          try {
-            walk();
-          } catch (err) {
-            console.error(err.stack);
+      chokidar
+        .watch(filenames, {
+          persistent: true,
+          ignoreInitial: true,
+          awaitWriteFinish: {
+            stabilityThreshold: 50,
+            pollInterval: 10,
+          },
+        })
+        .on("all", function(type, filename) {
+          if (!util.isCompilableExtension(filename, commander.extensions)) {
+            return;
           }
-        }
-      });
+
+          if (type === "add" || type === "change") {
+            util.log(type + " " + filename);
+            try {
+              walk();
+            } catch (err) {
+              console.error(err.stack);
+            }
+          }
+        });
     }
   };
 

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

@@ -34,45 +34,117 @@ function collect(value, previousValue): Array<string> {
 
 /* eslint-disable max-len */
 // Standard Babel input configs.
-commander.option("-f, --filename [filename]", "filename to use when reading from stdin - this will be used in source-maps, errors etc");
-commander.option("--presets [list]", "comma-separated list of preset names", collect);
-commander.option("--plugins [list]", "comma-separated list of plugin names", collect);
+commander.option(
+  "-f, --filename [filename]",
+  "filename to use when reading from stdin - this will be used in source-maps, errors etc",
+);
+commander.option(
+  "--presets [list]",
+  "comma-separated list of preset names",
+  collect,
+);
+commander.option(
+  "--plugins [list]",
+  "comma-separated list of plugin names",
+  collect,
+);
 
 // Basic file input configuration.
 commander.option("--source-type [script|module]", "");
-commander.option("--no-babelrc", "Whether or not to look up .babelrc and .babelignore files");
-commander.option("--ignore [list]", "list of glob paths to **not** compile", collect);
-commander.option("--only [list]", "list of glob paths to **only** compile", collect);
+commander.option(
+  "--no-babelrc",
+  "Whether or not to look up .babelrc and .babelignore files",
+);
+commander.option(
+  "--ignore [list]",
+  "list of glob paths to **not** compile",
+  collect,
+);
+commander.option(
+  "--only [list]",
+  "list of glob paths to **only** compile",
+  collect,
+);
 
 // Misc babel config.
-commander.option("--no-highlight-code", "enable/disable ANSI syntax highlighting of code frames (on by default)");
+commander.option(
+  "--no-highlight-code",
+  "enable/disable ANSI syntax highlighting of code frames (on by default)",
+);
 
 // General output formatting.
-commander.option("--no-comments", "write comments to generated output (true by default)");
-commander.option("--retain-lines", "retain line numbers - will result in really ugly code");
-commander.option("--compact [true|false|auto]", "do not include superfluous whitespace characters and line terminators", booleanify);
+commander.option(
+  "--no-comments",
+  "write comments to generated output (true by default)",
+);
+commander.option(
+  "--retain-lines",
+  "retain line numbers - will result in really ugly code",
+);
+commander.option(
+  "--compact [true|false|auto]",
+  "do not include superfluous whitespace characters and line terminators",
+  booleanify,
+);
 commander.option("--minified", "save as much bytes when printing [true|false]");
-commander.option("--auxiliary-comment-before [string]", "print a comment before any injected non-user code");
-commander.option("--auxiliary-comment-after [string]", "print a comment after any injected non-user code");
+commander.option(
+  "--auxiliary-comment-before [string]",
+  "print a comment before any injected non-user code",
+);
+commander.option(
+  "--auxiliary-comment-after [string]",
+  "print a comment after any injected non-user code",
+);
 
 // General soucemap formatting.
 commander.option("-s, --source-maps [true|false|inline|both]", "", booleanify);
-commander.option("--source-map-target [string]", "set `file` on returned source map");
-commander.option("--source-file-name [string]", "set `sources[0]` on returned source map");
-commander.option("--source-root [filename]", "the root from which all sources are relative");
+commander.option(
+  "--source-map-target [string]",
+  "set `file` on returned source map",
+);
+commander.option(
+  "--source-file-name [string]",
+  "set `sources[0]` on returned source map",
+);
+commander.option(
+  "--source-root [filename]",
+  "the root from which all sources are relative",
+);
 
 // Config params for certain module output formats.
-commander.option("--module-root [filename]", "optional prefix for the AMD module formatter that will be prepend to the filename on module definitions");
+commander.option(
+  "--module-root [filename]",
+  "optional prefix for the AMD module formatter that will be prepend to the filename on module definitions",
+);
 commander.option("-M, --module-ids", "insert an explicit id for modules");
-commander.option("--module-id [string]", "specify a custom name for module ids");
+commander.option(
+  "--module-id [string]",
+  "specify a custom name for module ids",
+);
 
 // "babel" command specific arguments that are not passed to babel-core.
-commander.option("-x, --extensions [extensions]", "List of extensions to compile when a directory has been input [.es6,.js,.es,.jsx,.mjs]", collect);
+commander.option(
+  "-x, --extensions [extensions]",
+  "List of extensions to compile when a directory has been input [.es6,.js,.es,.jsx,.mjs]",
+  collect,
+);
 commander.option("-w, --watch", "Recompile files on changes");
-commander.option("--skip-initial-build", "Do not compile files before watching");
-commander.option("-o, --out-file [out]", "Compile all input files into a single file");
-commander.option("-d, --out-dir [out]", "Compile an input directory of modules into an output directory");
-commander.option("-D, --copy-files", "When compiling a directory copy over non-compilable files");
+commander.option(
+  "--skip-initial-build",
+  "Do not compile files before watching",
+);
+commander.option(
+  "-o, --out-file [out]",
+  "Compile all input files into a single file",
+);
+commander.option(
+  "-d, --out-dir [out]",
+  "Compile an input directory of modules into an output directory",
+);
+commander.option(
+  "-D, --copy-files",
+  "When compiling a directory copy over non-compilable files",
+);
 commander.option("-q, --quiet", "Don't log anything");
 /* eslint-enable max-len */
 
@@ -84,7 +156,7 @@ commander.parse(process.argv);
 
 const errors = [];
 
-let filenames = commander.args.reduce(function (globbed, input) {
+let filenames = commander.args.reduce(function(globbed, input) {
   let files = glob.sync(input);
   if (!files.length) files = [input];
   return globbed.concat(files);
@@ -92,7 +164,7 @@ let filenames = commander.args.reduce(function (globbed, input) {
 
 filenames = uniq(filenames);
 
-filenames.forEach(function (filename) {
+filenames.forEach(function(filename) {
   if (!fs.existsSync(filename)) {
     errors.push(filename + " doesn't exist");
   }

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

@@ -10,8 +10,8 @@ export function chmod(src, dest) {
 }
 
 export function readdirFilter(filename) {
-  return readdir(filename).filter(function (filename) {
-    return babel.util.isCompilableExtension(filename);
+  return readdir(filename).filter(function(filename) {
+    return isCompilableExtension(filename);
   });
 }
 
@@ -20,7 +20,10 @@ export { readdir };
 /**
  * Test if a filename ends with a compilable extension.
  */
-export function isCompilableExtension(filename: string, altExts?: Array<string>): boolean {
+export function isCompilableExtension(
+  filename: string,
+  altExts?: Array<string>,
+): boolean {
   const exts = altExts || babel.DEFAULT_EXTENSIONS;
   const ext = path.extname(filename);
   return includes(exts, ext);
@@ -63,7 +66,7 @@ function toErrorStack(err) {
   }
 }
 
-process.on("uncaughtException", function (err) {
+process.on("uncaughtException", function(err) {
   console.error(toErrorStack(err));
   process.exit(1);
 });
@@ -74,7 +77,7 @@ export function requireChokidar() {
   } catch (err) {
     console.error(
       "The optional dependency chokidar failed to install and is required for " +
-      "--watch. Chokidar is likely not supported on your platform."
+        "--watch. Chokidar is likely not supported on your platform.",
     );
     throw err;
   }

packages/babel-cli/test/fixtures/babel-node/v8Flag-dashed-with-param/options.json

@@ -1,4 +1,4 @@
 {
-  "args": ["--expose-debug-as=customDebug", "--eval", "console.log(customDebug.Debug.DebugEvent.Break)"],
-  "stdout": "1"
+  "args": ["--expose-gc-as=garbageCollector", "--eval", "console.log(typeof global.garbageCollector)"],
+  "stdout": "function"
 }

packages/babel-cli/test/fixtures/babel-node/v8Flag-underscored-with-param/options.json

@@ -1,4 +1,4 @@
 {
-  "args": ["--expose_debug_as=customDebug", "--eval", "console.log(customDebug.Debug.DebugEvent.Break)"],
-  "stdout": "1"
+  "args": ["--expose_gc_as=garbageCollector", "--eval", "console.log(typeof global.garbageCollector)"],
+  "stdout": "function"
 }

packages/babel-cli/test/fixtures/babel/filename default comments/out-files/script2.js

@@ -3,9 +3,6 @@
 /*
  Test comment
  */
-
 arr.map(function (x) {
   return x * MULTIPLIER;
-});
-
-// END OF FILE
+}); // END OF FILE

packages/babel-cli/test/index.js

@@ -27,34 +27,39 @@ const pluginLocs = [
   path.join(__dirname, "/../../babel-plugin-transform-es2015-modules-commonjs"),
 ].join(",");
 
-const readDir = function (loc, filter) {
+const readDir = function(loc, filter) {
   const files = {};
   if (fs.existsSync(loc)) {
-    readdir(loc, filter).forEach(function (filename) {
+    readdir(loc, filter).forEach(function(filename) {
       files[filename] = helper.readFile(path.join(loc, filename));
     });
   }
   return files;
 };
 
-const saveInFiles = function (files) {
+const saveInFiles = function(files) {
   // Place an empty .babelrc in each test so tests won't unexpectedly get to repo-level config.
   outputFileSync(".babelrc", "{}");
 
-  Object.keys(files).forEach(function (filename) {
+  Object.keys(files).forEach(function(filename) {
     const content = files[filename];
     outputFileSync(filename, content);
   });
 };
 
-const assertTest = function (stdout, stderr, opts) {
+const assertTest = function(stdout, stderr, opts) {
   const expectStderr = opts.stderr.trim();
   stderr = stderr.trim();
 
   if (opts.stderr) {
     if (opts.stderrContains) {
-      assert.ok(includes(stderr, expectStderr), "stderr " + JSON.stringify(stderr) +
-        " didn't contain " + JSON.stringify(expectStderr));
+      assert.ok(
+        includes(stderr, expectStderr),
+        "stderr " +
+          JSON.stringify(stderr) +
+          " didn't contain " +
+          JSON.stringify(expectStderr),
+      );
     } else {
       chai.expect(stderr).to.equal(expectStderr, "stderr didn't match");
     }
@@ -68,8 +73,13 @@ const assertTest = function (stdout, stderr, opts) {
 
   if (opts.stdout) {
     if (opts.stdoutContains) {
-      assert.ok(includes(stdout, expectStdout), "stdout " + JSON.stringify(stdout) +
-        " didn't contain " + JSON.stringify(expectStdout));
+      assert.ok(
+        includes(stdout, expectStdout),
+        "stdout " +
+          JSON.stringify(stdout) +
+          " didn't contain " +
+          JSON.stringify(expectStdout),
+      );
     } else {
       chai.expect(stdout).to.equal(expectStdout, "stdout didn't match");
     }
@@ -80,30 +90,34 @@ const assertTest = function (stdout, stderr, opts) {
   if (opts.outFiles) {
     const actualFiles = readDir(path.join(tmpLoc));
 
-    Object.keys(actualFiles).forEach(function (filename) {
+    Object.keys(actualFiles).forEach(function(filename) {
       if (!opts.inFiles.hasOwnProperty(filename)) {
         const expect = opts.outFiles[filename];
         const actual = actualFiles[filename];
 
-        chai.expect(expect, "Output is missing: " + filename).to.not.be.undefined;
+        chai.expect(expect, "Output is missing: " + filename).to.not.be
+          .undefined;
 
         if (expect) {
-          chai.expect(actual).to.equal(expect, "Compiled output does not match: " + filename);
+          chai
+            .expect(actual)
+            .to.equal(expect, "Compiled output does not match: " + filename);
         }
       }
     });
 
     Object.keys(opts.outFiles).forEach(function(filename) {
-      chai.expect(actualFiles, "Extraneous file in output: " + filename)
+      chai
+        .expect(actualFiles, "Extraneous file in output: " + filename)
         .to.contain.key(filename);
     });
   }
 };
 
-const buildTest = function (binName, testName, opts) {
+const buildTest = function(binName, testName, opts) {
   const binLoc = path.join(__dirname, "../lib", binName);
 
-  return function (callback) {
+  return function(callback) {
     clear();
     saveInFiles(opts.inFiles);
 
@@ -124,15 +138,15 @@ const buildTest = function (binName, testName, opts) {
     let stderr = "";
     let stdout = "";
 
-    spawn.stderr.on("data", function (chunk) {
+    spawn.stderr.on("data", function(chunk) {
       stderr += chunk;
     });
 
-    spawn.stdout.on("data", function (chunk) {
+    spawn.stdout.on("data", function(chunk) {
       stdout += chunk;
     });
 
-    spawn.on("close", function () {
+    spawn.on("close", function() {
       let err;
 
       try {
@@ -142,7 +156,8 @@ const buildTest = function (binName, testName, opts) {
       }
 
       if (err) {
-        err.message = args.map((arg) => `"${ arg }"`).join(" ") + ": " + err.message;
+        err.message =
+          args.map(arg => `"${arg}"`).join(" ") + ": " + err.message;
       }
 
       callback(err);
@@ -155,19 +170,19 @@ const buildTest = function (binName, testName, opts) {
   };
 };
 
-const clear = function () {
+const clear = function() {
   process.chdir(__dirname);
   if (fs.existsSync(tmpLoc)) rimraf.sync(tmpLoc);
   fs.mkdirSync(tmpLoc);
   process.chdir(tmpLoc);
 };
 
-fs.readdirSync(fixtureLoc).forEach(function (binName) {
+fs.readdirSync(fixtureLoc).forEach(function(binName) {
   if (binName[0] === ".") return;
 
   const suiteLoc = path.join(fixtureLoc, binName);
-  describe("bin/" + binName, function () {
-    fs.readdirSync(suiteLoc).forEach(function (testName) {
+  describe("bin/" + binName, function() {
+    fs.readdirSync(suiteLoc).forEach(function(testName) {
       if (testName[0] === ".") return;
 
       const testLoc = path.join(suiteLoc, testName);
@@ -179,7 +194,7 @@ fs.readdirSync(fixtureLoc).forEach(function (binName) {
       const optionsLoc = path.join(testLoc, "options.json");
       if (fs.existsSync(optionsLoc)) merge(opts, require(optionsLoc));
 
-      ["stdout", "stdin", "stderr"].forEach(function (key) {
+      ["stdout", "stdin", "stderr"].forEach(function(key) {
         const loc = path.join(testLoc, key + ".txt");
         if (fs.existsSync(loc)) {
           opts[key] = helper.readFile(loc);

packages/babel-code-frame/package.json

@@ -1,6 +1,6 @@
 {
   "name": "babel-code-frame",
-  "version": "7.0.0-alpha.12",
+  "version": "7.0.0-alpha.19",
   "description": "Generate errors that contain a code frame that point to source locations.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -8,8 +8,11 @@
   "repository": "https://github.com/babel/babel/tree/master/packages/babel-code-frame",
   "main": "lib/index.js",
   "dependencies": {
-    "chalk": "^1.1.0",
+    "chalk": "^2.0.0",
     "esutils": "^2.0.2",
     "js-tokens": "^3.0.0"
+  },
+  "devDependencies": {
+    "strip-ansi": "^4.0.0"
   }
 }

packages/babel-code-frame/src/index.js

@@ -90,11 +90,11 @@ function getTokenType(match) {
  */
 
 function highlight(defs: Object, text: string) {
-  return text.replace(jsTokens, function (...args) {
+  return text.replace(jsTokens, function(...args) {
     const type = getTokenType(args);
     const colorize = defs[type];
     if (colorize) {
-      return args[0].split(NEWLINE).map((str) => colorize(str)).join("\n");
+      return args[0].split(NEWLINE).map(str => colorize(str)).join("\n");
     } else {
       return args[0];
     }
@@ -106,9 +106,15 @@ function highlight(defs: Object, text: string) {
  */
 
 function getMarkerLines(
-  loc: NodeLocation, source: Array<string>, opts: Object
+  loc: NodeLocation,
+  source: Array<string>,
+  opts: Object,
 ): { start: number, end: number, markerLines: Object } {
-  const startLoc: Location = Object.assign({}, { column: 0, line: -1 }, loc.start);
+  const startLoc: Location = Object.assign(
+    {},
+    { column: 0, line: -1 },
+    loc.start,
+  );
   const endLoc: Location = Object.assign({}, startLoc, loc.end);
   const linesAbove = opts.linesAbove || 2;
   const linesBelow = opts.linesBelow || 3;
@@ -165,12 +171,13 @@ function getMarkerLines(
   return { start, end, markerLines };
 }
 
-export function codeFrameColumns (
+export function codeFrameColumns(
   rawLines: string,
   loc: NodeLocation,
   opts: Object = {},
 ): string {
-  const highlighted = (opts.highlightCode && Chalk.supportsColor) || opts.forceColor;
+  const highlighted =
+    (opts.highlightCode && Chalk.supportsColor) || opts.forceColor;
   let chalk = Chalk;
   if (opts.forceColor) {
     chalk = new Chalk.constructor({ enabled: true });
@@ -186,34 +193,39 @@ export function codeFrameColumns (
 
   const numberMaxWidth = String(end).length;
 
-  const frame = lines.slice(start, end).map((line, index) => {
-    const number = start + 1 + index;
-    const paddedNumber = ` ${number}`.slice(-numberMaxWidth);
-    const gutter = ` ${paddedNumber} | `;
-    const hasMarker = markerLines[number];
-    if (hasMarker) {
-      let markerLine = "";
-      if (Array.isArray(hasMarker)) {
-        const markerSpacing = line.slice(0, Math.max(hasMarker[0] - 1, 0)).replace(/[^\t]/g, " ");
-        const numberOfMarkers = hasMarker[1] || 1;
+  const frame = lines
+    .slice(start, end)
+    .map((line, index) => {
+      const number = start + 1 + index;
+      const paddedNumber = ` ${number}`.slice(-numberMaxWidth);
+      const gutter = ` ${paddedNumber} | `;
+      const hasMarker = markerLines[number];
+      if (hasMarker) {
+        let markerLine = "";
+        if (Array.isArray(hasMarker)) {
+          const markerSpacing = line
+            .slice(0, Math.max(hasMarker[0] - 1, 0))
+            .replace(/[^\t]/g, " ");
+          const numberOfMarkers = hasMarker[1] || 1;
 
-        markerLine = [
-          "\n ",
-          maybeHighlight(defs.gutter, gutter.replace(/\d/g, " ")),
-          markerSpacing,
-          maybeHighlight(defs.marker, "^").repeat(numberOfMarkers),
+          markerLine = [
+            "\n ",
+            maybeHighlight(defs.gutter, gutter.replace(/\d/g, " ")),
+            markerSpacing,
+            maybeHighlight(defs.marker, "^").repeat(numberOfMarkers),
+          ].join("");
+        }
+        return [
+          maybeHighlight(defs.marker, ">"),
+          maybeHighlight(defs.gutter, gutter),
+          line,
+          markerLine,
         ].join("");
+      } else {
+        return ` ${maybeHighlight(defs.gutter, gutter)}${line}`;
       }
-      return [
-        maybeHighlight(defs.marker, ">"),
-        maybeHighlight(defs.gutter, gutter),
-        line,
-        markerLine,
-      ].join("");
-    } else {
-      return ` ${maybeHighlight(defs.gutter, gutter)}${line}`;
-    }
-  }).join("\n");
+    })
+    .join("\n");
 
   if (highlighted) {
     return chalk.reset(frame);
@@ -226,7 +238,7 @@ export function codeFrameColumns (
  * Create a code frame, adding line numbers, code highlighting, and pointing to a given position.
  */
 
-export default function (
+export default function(
   rawLines: string,
   lineNumber: number,
   colNumber: ?number,
@@ -236,7 +248,7 @@ export default function (
     deprecationWarningShown = true;
 
     const deprecationError = new Error(
-      "Passing lineNumber and colNumber is deprecated to babel-code-frame. Please use `codeFrameColumns`."
+      "Passing lineNumber and colNumber is deprecated to babel-code-frame. Please use `codeFrameColumns`.",
     );
     deprecationError.name = "DeprecationWarning";
 
@@ -249,7 +261,9 @@ export default function (
 
   colNumber = Math.max(colNumber, 0);
 
-  const location: NodeLocation = { start: { column: colNumber, line: lineNumber } };
+  const location: NodeLocation = {
+    start: { column: colNumber, line: lineNumber },
+  };
 
   return codeFrameColumns(rawLines, location, opts);
 }

packages/babel-code-frame/test/index.js

@@ -1,36 +1,31 @@
 import assert from "assert";
 import chalk from "chalk";
+import stripAnsi from "strip-ansi";
 import codeFrame, { codeFrameColumns } from "..";
 
-describe("babel-code-frame", function () {
-  it("basic usage", function () {
-    const rawLines = [
-      "class Foo {",
-      "  constructor()",
-      "};",
-    ].join("\n");
-    assert.equal(codeFrame(rawLines, 2, 16), [
-      "  1 | class Foo {",
-      "> 2 |   constructor()",
-      "    |                ^",
-      "  3 | };",
-    ].join("\n"));
+describe("babel-code-frame", function() {
+  it("basic usage", function() {
+    const rawLines = ["class Foo {", "  constructor()", "};"].join("\n");
+    assert.equal(
+      codeFrame(rawLines, 2, 16),
+      [
+        "  1 | class Foo {",
+        "> 2 |   constructor()",
+        "    |                ^",
+        "  3 | };",
+      ].join("\n"),
+    );
   });
 
-  it("optional column number", function () {
-    const rawLines = [
-      "class Foo {",
-      "  constructor()",
-      "};",
-    ].join("\n");
-    assert.equal(codeFrame(rawLines, 2, null), [
-      "  1 | class Foo {",
-      "> 2 |   constructor()",
-      "  3 | };",
-    ].join("\n"));
+  it("optional column number", function() {
+    const rawLines = ["class Foo {", "  constructor()", "};"].join("\n");
+    assert.equal(
+      codeFrame(rawLines, 2, null),
+      ["  1 | class Foo {", "> 2 |   constructor()", "  3 | };"].join("\n"),
+    );
   });
 
-  it("maximum context lines and padding", function () {
+  it("maximum context lines and padding", function() {
     const rawLines = [
       "/**",
       " * Sums two numbers.",
@@ -44,18 +39,21 @@ describe("babel-code-frame", function () {
       "  return a + b",
       "}",
     ].join("\n");
-    assert.equal(codeFrame(rawLines, 7, 2), [
-      "   5 |  * @param b Number",
-      "   6 |  * @returns Number",
-      ">  7 |  */",
-      "     |  ^",
-      "   8 | ",
-      "   9 | function sum(a, b) {",
-      "  10 |   return a + b",
-    ].join("\n"));
+    assert.equal(
+      codeFrame(rawLines, 7, 2),
+      [
+        "   5 |  * @param b Number",
+        "   6 |  * @returns Number",
+        ">  7 |  */",
+        "     |  ^",
+        "   8 | ",
+        "   9 | function sum(a, b) {",
+        "  10 |   return a + b",
+      ].join("\n"),
+    );
   });
 
-  it("no unnecessary padding due to one-off errors", function () {
+  it("no unnecessary padding due to one-off errors", function() {
     const rawLines = [
       "/**",
       " * Sums two numbers.",
@@ -69,43 +67,49 @@ describe("babel-code-frame", function () {
       "  return a + b",
       "}",
     ].join("\n");
-    assert.equal(codeFrame(rawLines, 6, 2), [
-      "  4 |  * @param a Number",
-      "  5 |  * @param b Number",
-      "> 6 |  * @returns Number",
-      "    |  ^",
-      "  7 |  */",
-      "  8 | ",
-      "  9 | function sum(a, b) {",
-    ].join("\n"));
+    assert.equal(
+      codeFrame(rawLines, 6, 2),
+      [
+        "  4 |  * @param a Number",
+        "  5 |  * @param b Number",
+        "> 6 |  * @returns Number",
+        "    |  ^",
+        "  7 |  */",
+        "  8 | ",
+        "  9 | function sum(a, b) {",
+      ].join("\n"),
+    );
   });
 
-  it("tabs", function () {
+  it("tabs", function() {
     const rawLines = [
       "\tclass Foo {",
       "\t  \t\t    constructor\t(\t)",
       "\t};",
     ].join("\n");
-    assert.equal(codeFrame(rawLines, 2, 25), [
-      "  1 | \tclass Foo {",
-      "> 2 | \t  \t\t    constructor\t(\t)",
-      "    | \t  \t\t               \t \t ^",
-      "  3 | \t};",
-    ].join("\n"));
+    assert.equal(
+      codeFrame(rawLines, 2, 25),
+      [
+        "  1 | \tclass Foo {",
+        "> 2 | \t  \t\t    constructor\t(\t)",
+        "    | \t  \t\t               \t \t ^",
+        "  3 | \t};",
+      ].join("\n"),
+    );
   });
 
-  it("opts.highlightCode", function () {
+  it("opts.highlightCode", function() {
     const rawLines = "console.log('babel')";
     const result = codeFrame(rawLines, 1, 9, { highlightCode: true });
-    const stripped = chalk.stripColor(result);
+    const stripped = stripAnsi(result);
     assert.ok(result.length > stripped.length);
-    assert.equal(stripped, [
-      "> 1 | console.log('babel')",
-      "    |         ^",
-    ].join("\n"));
+    assert.equal(
+      stripped,
+      ["> 1 | console.log('babel')", "    |         ^"].join("\n"),
+    );
   });
 
-  it("opts.linesAbove", function () {
+  it("opts.linesAbove", function() {
     const rawLines = [
       "/**",
       " * Sums two numbers.",
@@ -119,17 +123,20 @@ describe("babel-code-frame", function () {
       "  return a + b",
       "}",
     ].join("\n");
-    assert.equal(codeFrame(rawLines, 7, 2, { linesAbove: 1 }), [
-      "   6 |  * @returns Number",
-      ">  7 |  */",
-      "     |  ^",
-      "   8 | ",
-      "   9 | function sum(a, b) {",
-      "  10 |   return a + b",
-    ].join("\n"));
+    assert.equal(
+      codeFrame(rawLines, 7, 2, { linesAbove: 1 }),
+      [
+        "   6 |  * @returns Number",
+        ">  7 |  */",
+        "     |  ^",
+        "   8 | ",
+        "   9 | function sum(a, b) {",
+        "  10 |   return a + b",
+      ].join("\n"),
+    );
   });
 
-  it("opts.linesBelow", function () {
+  it("opts.linesBelow", function() {
     const rawLines = [
       "/**",
       " * Sums two numbers.",
@@ -143,16 +150,19 @@ describe("babel-code-frame", function () {
       "  return a + b",
       "}",
     ].join("\n");
-    assert.equal(codeFrame(rawLines, 7, 2, { linesBelow: 1 }), [
-      "  5 |  * @param b Number",
-      "  6 |  * @returns Number",
-      "> 7 |  */",
-      "    |  ^",
-      "  8 | ",
-    ].join("\n"));
+    assert.equal(
+      codeFrame(rawLines, 7, 2, { linesBelow: 1 }),
+      [
+        "  5 |  * @param b Number",
+        "  6 |  * @returns Number",
+        "> 7 |  */",
+        "    |  ^",
+        "  8 | ",
+      ].join("\n"),
+    );
   });
 
-  it("opts.linesAbove and opts.linesBelow", function () {
+  it("opts.linesAbove and opts.linesBelow", function() {
     const rawLines = [
       "/**",
       " * Sums two numbers.",
@@ -166,78 +176,82 @@ describe("babel-code-frame", function () {
       "  return a + b",
       "}",
     ].join("\n");
-    assert.equal(codeFrame(rawLines, 7, 2, { linesAbove: 1, linesBelow: 1 }), [
-      "  6 |  * @returns Number",
-      "> 7 |  */",
-      "    |  ^",
-      "  8 | ",
-    ].join("\n"));
+    assert.equal(
+      codeFrame(rawLines, 7, 2, { linesAbove: 1, linesBelow: 1 }),
+      ["  6 |  * @returns Number", "> 7 |  */", "    |  ^", "  8 | "].join(
+        "\n",
+      ),
+    );
   });
 
   it("opts.forceColor", function() {
     const marker = chalk.red.bold;
     const gutter = chalk.grey;
 
-    const rawLines = [
-      "",
-      "",
-      "",
-      "",
-    ].join("\n");
-    assert.equal(codeFrame(rawLines, 3, null, { linesAbove: 1, linesBelow: 1, forceColor: true }),
-      chalk.reset([
-        " " + gutter(" 2 | "),
-        marker(">") + gutter(" 3 | "),
-        " " + gutter(" 4 | "),
-      ].join("\n"))
+    const rawLines = ["", "", "", ""].join("\n");
+    assert.equal(
+      codeFrame(rawLines, 3, null, {
+        linesAbove: 1,
+        linesBelow: 1,
+        forceColor: true,
+      }),
+      chalk.reset(
+        [
+          " " + gutter(" 2 | "),
+          marker(">") + gutter(" 3 | "),
+          " " + gutter(" 4 | "),
+        ].join("\n"),
+      ),
     );
   });
 
-  it("basic usage, new API", function () {
-    const rawLines = [
-      "class Foo {",
-      "  constructor()",
-      "};",
-    ].join("\n");
-    assert.equal(codeFrameColumns(rawLines, { start: { line: 2, column: 16 } }), [
-      "  1 | class Foo {",
-      "> 2 |   constructor()",
-      "    |                ^",
-      "  3 | };",
-    ].join("\n"));
+  it("basic usage, new API", function() {
+    const rawLines = ["class Foo {", "  constructor()", "};"].join("\n");
+    assert.equal(
+      codeFrameColumns(rawLines, { start: { line: 2, column: 16 } }),
+      [
+        "  1 | class Foo {",
+        "> 2 |   constructor()",
+        "    |                ^",
+        "  3 | };",
+      ].join("\n"),
+    );
   });
 
   it("mark multiple columns", function() {
-    const rawLines = [
-      "class Foo {",
-      "  constructor()",
-      "};",
-    ].join("\n");
+    const rawLines = ["class Foo {", "  constructor()", "};"].join("\n");
     assert.equal(
-      codeFrameColumns(rawLines, { start: { line: 2, column: 3 }, end: { line: 2, column: 16 } }), [
+      codeFrameColumns(rawLines, {
+        start: { line: 2, column: 3 },
+        end: { line: 2, column: 16 },
+      }),
+      [
         "  1 | class Foo {",
         "> 2 |   constructor()",
         "    |   ^^^^^^^^^^^^^",
         "  3 | };",
-      ].join("\n"));
+      ].join("\n"),
+    );
   });
 
   it("mark multiple columns across lines", function() {
-    const rawLines = [
-      "class Foo {",
-      "  constructor() {",
-      "  }",
-      "};",
-    ].join("\n");
+    const rawLines = ["class Foo {", "  constructor() {", "  }", "};"].join(
+      "\n",
+    );
     assert.equal(
-      codeFrameColumns(rawLines, { start: { line: 2, column: 17 }, end: { line: 3, column: 3 } }), [
+      codeFrameColumns(rawLines, {
+        start: { line: 2, column: 17 },
+        end: { line: 3, column: 3 },
+      }),
+      [
         "  1 | class Foo {",
         "> 2 |   constructor() {",
         "    |                 ^",
         "> 3 |   }",
         "    | ^^^",
         "  4 | };",
-      ].join("\n"));
+      ].join("\n"),
+    );
   });
 
   it("mark multiple columns across multiple lines", function() {
@@ -249,7 +263,11 @@ describe("babel-code-frame", function () {
       "};",
     ].join("\n");
     assert.equal(
-      codeFrameColumns(rawLines, { start: { line: 2, column: 17 }, end: { line: 4, column: 3 } }), [
+      codeFrameColumns(rawLines, {
+        start: { line: 2, column: 17 },
+        end: { line: 4, column: 3 },
+      }),
+      [
         "  1 | class Foo {",
         "> 2 |   constructor() {",
         "    |                 ^",
@@ -258,7 +276,8 @@ describe("babel-code-frame", function () {
         "> 4 |   }",
         "    | ^^^",
         "  5 | };",
-      ].join("\n"));
+      ].join("\n"),
+    );
   });
 
   it("mark across multiple lines without columns", function() {
@@ -270,12 +289,14 @@ describe("babel-code-frame", function () {
       "};",
     ].join("\n");
     assert.equal(
-      codeFrameColumns(rawLines, { start: { line: 2 }, end: { line: 4 } }), [
+      codeFrameColumns(rawLines, { start: { line: 2 }, end: { line: 4 } }),
+      [
         "  1 | class Foo {",
         "> 2 |   constructor() {",
         "> 3 |     console.log(arguments);",
         "> 4 |   }",
         "  5 | };",
-      ].join("\n"));
+      ].join("\n"),
+    );
   });
 });

packages/babel-core/README.md

@@ -5,11 +5,11 @@
 
 ```javascript
 var babel = require("babel-core");
-import { transform } from 'babel-core';
-import * as babel from 'babel-core';
+import { transform } from "babel-core";
+import * as babel from "babel-core";
 ```
 
-All transformations will use your local configuration files (.babelrc or in package.json). See [options](#options) to disable it.
+All transformations will use your local configuration files (`.babelrc` or in `package.json`). See [options](#options) to disable it.
 
 ## babel.transform(code: string, [options?](#options): Object)
 
@@ -62,7 +62,7 @@ babel.transformFileSync("filename.js", options).code;
 
 ## babel.transformFromAst(ast: Object, code?: string, [options?](#options): Object)
 
-Given, an [AST](https://astexplorer.net/), transform it.
+Given an [AST](https://astexplorer.net/), transform it.
 
 ```js
 const sourceCode = "if (true) return;";
@@ -87,35 +87,35 @@ Following is a table of the options you can use:
 | Option                   | Default              | Description                     |
 | ------------------------ | -------------------- | ------------------------------- |
 | `ast`                    | `true`               | Include the AST in the returned object |
-| `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). |
+| `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) |
 | `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. |
+| `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"` |
-| `extends`                | `null`               | A path to an `.babelrc` file to extend |
-| `filename`               | `"unknown"`          | Filename for use in errors etc. |
-| `filenameRelative`       | `(filename)`         | Filename relative to `sourceRoot`. |
+| `extends`                | `null`               | A path to a `.babelrc` file to extend |
+| `filename`               | `"unknown"`          | Filename for use in errors etc |
+| `filenameRelative`       | `(filename)`         | Filename relative to `sourceRoot` |
 | `generatorOpts`          | `{}`                 | An object containing the options to be passed down to the babel code generator, babel-generator |
-| `getModuleId`            | `null`               | Specify a custom callback to generate a module id with. Called as `getModuleId(moduleName)`. If falsy value is returned then the generated module id is used. |
+| `getModuleId`            | `null`               | Specify a custom callback to generate a module id with. Called as `getModuleId(moduleName)`. If falsy value is returned then the generated module id is used |
 | `highlightCode`          | `true`               | ANSI highlight syntax error code frames |
-| `ignore`                 | `null`               | Opposite to the `only` option. `ignore` is disregarded if `only` is specified. |
-| `inputSourceMap`         | `null`               | A source map object that the output source map will be based on. |
+| `ignore`                 | `null`               | Opposite to the `only` option. `ignore` is disregarded if `only` is specified |
+| `inputSourceMap`         | `null`               | A source map object that the output source map will be based on |
 | `minified`               | `false`              | Should the output be minified (not printing last semicolons in blocks, printing literal string values instead of escaped ones, stripping `()` from `new` when safe) |
-| `moduleId`               | `null`               | Specify a custom name for module ids. |
+| `moduleId`               | `null`               | Specify a custom name for module ids |
 | `moduleIds`              | `false`              | If truthy, insert an explicit id for modules. By default, all modules are anonymous. (Not available for `common` modules) |
-| `moduleRoot`             | `(sourceRoot)`       | Optional prefix for the AMD module formatter that will be prepend to the filename on module definitions. |
-| `only`                   | `null`               | A [glob](https://github.com/isaacs/minimatch), regex, or mixed array of both, matching paths to **only** compile. Can also be an array of arrays containing paths to explicitly match. When attempting to compile a non-matching file it's returned verbatim. |
+| `moduleRoot`             | `(sourceRoot)`       | Optional prefix for the AMD module formatter that will be prepend to the filename on module definitions |
+| `only`                   | `null`               | A [glob](https://github.com/isaacs/minimatch), regex, or mixed array of both, matching paths to **only** compile. Can also be an array of arrays containing paths to explicitly match. When attempting to compile a non-matching file it's returned verbatim |
 | `parserOpts`             | `{}`                 | An object containing the options to be passed down to the babel parser, babylon |
-| `plugins`                | `[]`                 | List of [plugins](https://babeljs.io/docs/plugins/) to load and use. |
-| `presets`                | `[]`                 | List of [presets](https://babeljs.io/docs/plugins/#presets) (a set of plugins) to load and use. |
+| `plugins`                | `[]`                 | List of [plugins](https://babeljs.io/docs/plugins/) to load and use |
+| `presets`                | `[]`                 | List of [presets](https://babeljs.io/docs/plugins/#presets) (a set of plugins) to load and use |
 | `retainLines`            | `false`              | Retain line numbers. This will lead to wacky code but is handy for scenarios where you can't use source maps. (**NOTE:** This will not retain the columns) |
-| `resolveModuleSource`    | `null`               | Resolve a module source ie. `import "SOURCE";` to a custom value. Called as `resolveModuleSource(source, filename)`. |
-| `shouldPrintComment`     | `null`               | An optional callback that controls whether a comment should be output or not. Called as `shouldPrintComment(commentContents)`. **NOTE:** This overrides the `comment` option when used. |
-| `sourceFileName`         | `(filenameRelative)` | Set `sources[0]` on returned source map. |
-| `sourceMaps`             | `false`              | If truthy, adds a `map` property to returned output. If set to `"inline"`, a comment with a sourceMappingURL directive is added to the bottom of the returned code. If set to `"both"` then a `map` property is returned as well as a source map comment appended. **This does not emit sourcemap files by itself!** To have sourcemaps emitted using the CLI, you must pass it the `--source-maps` option. |
-| `sourceMapTarget`        | `(filenameRelative)` | Set `file` on returned source map. |
-| `sourceRoot`             | `(moduleRoot)`       | The root from which all sources are relative. |
-| `sourceType`             | `"module"`           | Indicate the mode the code should be parsed in. Can be either "script" or "module". |
+| `resolveModuleSource`    | `null`               | Resolve a module source ie. `import "SOURCE";` to a custom value. Called as `resolveModuleSource(source, filename)` |
+| `shouldPrintComment`     | `null`               | An optional callback that controls whether a comment should be output or not. Called as `shouldPrintComment(commentContents)`. **NOTE:** This overrides the `comment` option when used |
+| `sourceFileName`         | `(filenameRelative)` | Set `sources[0]` on returned source map |
+| `sourceMaps`             | `false`              | If truthy, adds a `map` property to returned output. If set to `"inline"`, a comment with a sourceMappingURL directive is added to the bottom of the returned code. If set to `"both"` then a `map` property is returned as well as a source map comment appended. **This does not emit sourcemap files by itself!** To have sourcemaps emitted using the CLI, you must pass it the `--source-maps` option |
+| `sourceMapTarget`        | `(filenameRelative)` | Set `file` on returned source map |
+| `sourceRoot`             | `(moduleRoot)`       | The root from which all sources are relative |
+| `sourceType`             | `"module"`           | Indicate the mode the code should be parsed in. Can be either "script" or "module" |
 | `wrapPluginVisitorMethod`| `null`               | An optional callback that can be used to wrap visitor methods. **NOTE:** This is useful for things like introspection, and not really needed for implementing anything. Called as `wrapPluginVisitorMethod(pluginAlias, visitorType, callback)`.

packages/babel-core/package.json

@@ -1,6 +1,6 @@
 {
   "name": "babel-core",
-  "version": "7.0.0-alpha.12",
+  "version": "7.0.0-alpha.19",
   "description": "Babel compiler core.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -25,28 +25,24 @@
     "./lib/config/loading/files/index.js": "./lib/config/loading/files/index-browser.js"
   },
   "dependencies": {
-    "babel-code-frame": "7.0.0-alpha.12",
-    "babel-generator": "7.0.0-alpha.12",
-    "babel-helpers": "7.0.0-alpha.12",
-    "babel-messages": "7.0.0-alpha.12",
-    "babel-template": "7.0.0-alpha.12",
-    "babel-traverse": "7.0.0-alpha.12",
-    "babel-types": "7.0.0-alpha.12",
-    "babylon": "7.0.0-beta.12",
+    "babel-code-frame": "7.0.0-alpha.19",
+    "babel-generator": "7.0.0-alpha.19",
+    "babel-helpers": "7.0.0-alpha.19",
+    "babel-messages": "7.0.0-alpha.19",
+    "babel-template": "7.0.0-alpha.19",
+    "babel-traverse": "7.0.0-alpha.19",
+    "babel-types": "7.0.0-alpha.19",
+    "babylon": "7.0.0-beta.19",
     "convert-source-map": "^1.1.0",
     "debug": "^2.1.1",
     "json5": "^0.5.0",
     "lodash": "^4.2.0",
     "micromatch": "^2.3.11",
-    "private": "^0.1.6",
     "resolve": "^1.3.2",
-    "slash": "^1.0.0",
     "source-map": "^0.5.0"
   },
   "devDependencies": {
-    "babel-helper-fixtures": "7.0.0-alpha.12",
-    "babel-helper-transform-fixture-test-runner": "7.0.0-alpha.12",
-    "babel-polyfill": "7.0.0-alpha.12",
-    "babel-register": "7.0.0-alpha.12"
+    "babel-helper-transform-fixture-test-runner": "7.0.0-alpha.19",
+    "babel-register": "7.0.0-alpha.19"
   }
 }

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

@@ -7,14 +7,14 @@ import micromatch from "micromatch";
 import { findConfigs, loadConfig } from "./loading/files";
 
 type ConfigItem = {
-  type: "options"|"arguments",
+  type: "options" | "arguments",
   options: {},
   dirname: string,
   alias: string,
   loc: string,
 };
 
-export default function buildConfigChain(opts: {}): Array<ConfigItem>|null {
+export default function buildConfigChain(opts: {}): Array<ConfigItem> | null {
   if (typeof opts.filename !== "string" && opts.filename != null) {
     throw new Error(".filename must be a string, null, or undefined");
   }
@@ -44,9 +44,9 @@ export default function buildConfigChain(opts: {}): Array<ConfigItem>|null {
 }
 
 class ConfigChainBuilder {
-  filename: string|null;
+  filename: string | null;
   configs: Array<ConfigItem>;
-  possibleDirs: null|Array<string>;
+  possibleDirs: null | Array<string>;
 
   constructor(filename) {
     this.configs = [];
@@ -57,16 +57,14 @@ class ConfigChainBuilder {
   /**
    * Tests if a filename should be ignored based on "ignore" and "only" options.
    */
-  shouldIgnore(
-    ignore: mixed,
-    only: mixed,
-    dirname: string,
-  ): boolean {
+  shouldIgnore(ignore: mixed, only: mixed, dirname: string): boolean {
     if (!this.filename) return false;
 
     if (ignore) {
       if (!Array.isArray(ignore)) {
-        throw new Error(`.ignore should be an array, ${JSON.stringify(ignore)} given`);
+        throw new Error(
+          `.ignore should be an array, ${JSON.stringify(ignore)} given`,
+        );
       }
 
       if (this.matchesPatterns(ignore, dirname)) return true;
@@ -74,7 +72,9 @@ class ConfigChainBuilder {
 
     if (only) {
       if (!Array.isArray(only)) {
-        throw new Error(`.only should be an array, ${JSON.stringify(only)} given`);
+        throw new Error(
+          `.only should be an array, ${JSON.stringify(only)} given`,
+        );
       }
 
       if (!this.matchesPatterns(only, dirname)) return true;
@@ -89,21 +89,27 @@ class ConfigChainBuilder {
    */
   matchesPatterns(patterns: Array<mixed>, dirname: string) {
     const filename = this.filename;
-    if (!filename) throw new Error("Assertion failure: .filename should always exist here");
+    if (!filename) {
+      throw new Error("Assertion failure: .filename should always exist here");
+    }
 
     const res = [];
     const strings = [];
     const fns = [];
 
-    patterns.forEach((pattern) => {
+    patterns.forEach(pattern => {
       if (typeof pattern === "string") strings.push(pattern);
       else if (typeof pattern === "function") fns.push(pattern);
       else if (pattern instanceof RegExp) res.push(pattern);
-      else throw new Error("Patterns must be a string, function, or regular expression");
+      else {
+        throw new Error(
+          "Patterns must be a string, function, or regular expression",
+        );
+      }
     });
 
-    if (res.some((re) => re.test(filename))) return true;
-    if (fns.some((fn) => fn(filename))) return true;
+    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;
@@ -123,7 +129,7 @@ class ConfigChainBuilder {
         }
       }
 
-      const absolutePatterns = strings.map((pattern) => {
+      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);
@@ -131,7 +137,9 @@ class ConfigChainBuilder {
         return (negate ? "!" : "") + path.resolve(dirname, pattern);
       });
 
-      if (micromatch(possibleDirs, absolutePatterns, { nocase: true }).length > 0) {
+      if (
+        micromatch(possibleDirs, absolutePatterns, { nocase: true }).length > 0
+      ) {
         return true;
       }
     }
@@ -150,16 +158,16 @@ class ConfigChainBuilder {
     });
   }
 
-  mergeConfig({
-    type,
-    options: rawOpts,
-    alias,
-    dirname,
-  }) {
+  mergeConfig({ type, options: rawOpts, alias, dirname }) {
     // Bail out ASAP if this file is ignored so that we run as little logic as possible on ignored files.
-    if (this.filename && this.shouldIgnore(rawOpts.ignore || null, rawOpts.only || null, dirname)) {
+    if (
+      this.filename &&
+      this.shouldIgnore(rawOpts.ignore || null, rawOpts.only || null, dirname)
+    ) {
       // TODO(logan): This is a really cross way to bail out. Avoid this in rewrite.
-      throw Object.assign((new Error("This file has been ignored."): any), { code: "BABEL_IGNORED_FILE" });
+      throw Object.assign((new Error("This file has been ignored."): any), {
+        code: "BABEL_IGNORED_FILE",
+      });
     }
 
     const options = Object.assign({}, rawOpts);
@@ -168,13 +176,19 @@ class ConfigChainBuilder {
 
     const envKey = getEnv();
 
-    if (rawOpts.env != null && (typeof rawOpts.env !== "object" || Array.isArray(rawOpts.env))) {
+    if (
+      rawOpts.env != null &&
+      (typeof rawOpts.env !== "object" || Array.isArray(rawOpts.env))
+    ) {
       throw new Error(".env block must be an object, null, or undefined");
     }
 
     const envOpts = rawOpts.env && rawOpts.env[envKey];
 
-    if (envOpts != null && (typeof envOpts !== "object" || Array.isArray(envOpts))) {
+    if (
+      envOpts != null &&
+      (typeof envOpts !== "object" || Array.isArray(envOpts))
+    ) {
       throw new Error(".env[...] block must be an object, null, or undefined");
     }
 
@@ -196,11 +210,13 @@ class ConfigChainBuilder {
     });
 
     if (rawOpts.extends) {
-      if (typeof rawOpts.extends !== "string") throw new Error(".extends must be a string");
+      if (typeof rawOpts.extends !== "string") {
+        throw new Error(".extends must be a string");
+      }
 
       const extendsConfig = loadConfig(rawOpts.extends, dirname);
 
-      const existingConfig = this.configs.some((config) => {
+      const existingConfig = this.configs.some(config => {
         return config.alias === extendsConfig.filepath;
       });
       if (!existingConfig) {
@@ -214,4 +230,3 @@ class ConfigChainBuilder {
     }
   }
 }
-

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

@@ -13,7 +13,7 @@ type CacheConfiguratorObj = {
   invalidate: <T>(handler: () => T) => T,
 };
 
-type CacheEntry<ResultT> = Array<[ ResultT, () => boolean ]>;
+type CacheEntry<ResultT> = Array<[ResultT, () => boolean]>;
 
 /**
  * Given a function with a single argument, cache its results based on its argument and how it
@@ -22,7 +22,7 @@ type CacheEntry<ResultT> = Array<[ ResultT, () => boolean ]>;
 export function makeStrongCache<ArgT, ResultT>(
   handler: (ArgT, CacheConfigurator) => ResultT,
   autoPermacache?: boolean,
-): (ArgT) => ResultT {
+): ArgT => ResultT {
   return makeCachedFunction(new Map(), handler, autoPermacache);
 }
 
@@ -34,22 +34,24 @@ export function makeStrongCache<ArgT, ResultT>(
 export function makeWeakCache<ArgT: {}, ResultT>(
   handler: (ArgT, CacheConfigurator) => ResultT,
   autoPermacache?: boolean,
-): (ArgT) => ResultT {
+): ArgT => ResultT {
   return makeCachedFunction(new WeakMap(), handler, autoPermacache);
 }
 
-type CacheMap<ArgT, ResultT> = Map<ArgT, CacheEntry<ResultT>>|WeakMap<ArgT, CacheEntry<ResultT>>;
+type CacheMap<ArgT, ResultT> =
+  | Map<ArgT, CacheEntry<ResultT>>
+  | WeakMap<ArgT, CacheEntry<ResultT>>;
 
 function makeCachedFunction<ArgT, ResultT, Cache: CacheMap<ArgT, ResultT>>(
   callCache: Cache,
   handler: (ArgT, CacheConfigurator) => ResultT,
   autoPermacache: boolean = true,
-): (ArgT) => ResultT {
+): ArgT => ResultT {
   return function cachedFunction(arg) {
-    let cachedValue: CacheEntry<ResultT>|void = callCache.get(arg);
+    let cachedValue: CacheEntry<ResultT> | void = callCache.get(arg);
 
     if (cachedValue) {
-      for (const [ value, valid ] of cachedValue) {
+      for (const [value, valid] of cachedValue) {
         if (valid()) return value;
       }
     }
@@ -64,55 +66,53 @@ function makeCachedFunction<ArgT, ResultT, Cache: CacheMap<ArgT, ResultT>>(
 
     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"));
+      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],
-        ];
+        cachedValue = [[value, () => true]];
       } else if (result.invalidate) {
-        cachedValue = [
-          [value, result.valid],
-        ];
+        cachedValue = [[value, result.valid]];
       } else {
         cachedValue = cachedValue || [];
-        cachedValue.push([ value, result.valid ]);
+        cachedValue.push([value, result.valid]);
       }
       callCache.set(arg, cachedValue);
     }
@@ -121,7 +121,11 @@ function makeCachedFunction<ArgT, ResultT, Cache: CacheMap<ArgT, ResultT>>(
   };
 }
 
-function makeCacheConfig(): { cache: CacheConfigurator, result: *, deactivate: () => void } {
+function makeCacheConfig(): {
+  cache: CacheConfigurator,
+  result: *,
+  deactivate: () => void,
+} {
   const pairs = [];
 
   const result = {
@@ -137,51 +141,80 @@ function makeCacheConfig(): { cache: CacheConfigurator, result: *, deactivate: (
     active = false;
   };
 
-  const cache: CacheConfigurator = Object.assign((function cacheFn(val) {
-    if (typeof val === "boolean") {
-      if (val) cache.forever();
-      else cache.never();
-      return;
-    }
-
-    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()");
+  const cache: CacheConfigurator = Object.assign(
+    (function cacheFn(val) {
+      if (typeof val === "boolean") {
+        if (val) cache.forever();
+        else cache.never();
+        return;
       }
-      result.configured = true;
 
-      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;
+      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;
 
-      const key = handler();
-      pairs.push([ key, handler ]);
-      return key;
-    },
-  }: CacheConfiguratorObj));
+        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;
+
+        const key = handler();
+        pairs.push([key, handler]);
+        return key;
+      },
+    }: CacheConfiguratorObj),
+  );
 
   return { cache, result, deactivate };
 }

packages/babel-core/src/config/helpers/environment.js

@@ -1,7 +1,5 @@
 // @flow
 
 export function getEnv(defaultValue: string = "development"): string {
-  return process.env.BABEL_ENV
-    || process.env.NODE_ENV
-    || defaultValue;
+  return process.env.BABEL_ENV || process.env.NODE_ENV || defaultValue;
 }

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

@@ -5,13 +5,13 @@ import manageOptions from "./option-manager";
 
 export type ResolvedConfig = {
   options: Object,
-  passes: Array<Array<[ Plugin, ?{} ]>>,
+  passes: Array<Array<[Plugin, ?{}]>>,
 };
 
 /**
  * Standard API for loading Babel configuration data. Not for public consumption.
  */
-export default function loadConfig(opts: mixed): ResolvedConfig|null {
+export default function loadConfig(opts: mixed): ResolvedConfig | null {
   if (opts != null && typeof opts !== "object") {
     throw new Error("Babel options must be an object, null, or undefined");
   }

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

@@ -41,13 +41,16 @@ export function findConfigs(dirname: string): Array<ConfigFile> {
         BABELRC_FILENAME,
         BABELRC_JS_FILENAME,
         PACKAGE_FILENAME,
-      ].reduce((previousConfig: ConfigFile|null, name) => {
+      ].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}`);
+          throw new Error(
+            `Multiple configuration files found. Please remove one:\n- ${path.basename(
+              previousConfig.filepath,
+            )}\n- ${name}\nfrom ${loc}`,
+          );
         }
 
         return config || previousConfig;
@@ -73,7 +76,9 @@ 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`);
+  if (!conf) {
+    throw new Error(`Config file ${filepath} contains no configuration data`);
+  }
 
   return conf;
 }
@@ -83,7 +88,9 @@ export function loadConfig(name: string, dirname: string): ConfigFile {
  * throw if there are parsing errors while loading a config.
  */
 function readConfig(filepath) {
-  return (path.extname(filepath) === ".js") ? readConfigJS(filepath) : readConfigFile(filepath);
+  return path.extname(filepath) === ".js"
+    ? readConfigJS(filepath)
+    : readConfigFile(filepath);
 }
 
 const readConfigJS = makeStrongCache((filepath, cache) => {
@@ -96,7 +103,10 @@ const readConfigJS = makeStrongCache((filepath, cache) => {
   try {
     // $FlowIssue
     const configModule = (require(filepath): mixed);
-    options = configModule && configModule.__esModule ? (configModule.default || undefined) : configModule;
+    options =
+      configModule && configModule.__esModule
+        ? configModule.default || undefined
+        : configModule;
   } catch (err) {
     err.message = `${filepath}: Error while loading config - ${err.message}`;
     throw err;
@@ -113,7 +123,9 @@ const readConfigJS = makeStrongCache((filepath, cache) => {
   }
 
   if (!options || typeof options !== "object" || Array.isArray(options)) {
-    throw new Error(`${filepath}: Configuration should be an exported JavaScript object.`);
+    throw new Error(
+      `${filepath}: Configuration should be an exported JavaScript object.`,
+    );
   }
 
   return {
@@ -144,8 +156,12 @@ const readConfigFile = makeStaticFileCache((filepath, content) => {
     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`);
+  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,
@@ -157,8 +173,8 @@ const readConfigFile = makeStaticFileCache((filepath, content) => {
 const readIgnoreConfig = makeStaticFileCache((filepath, content) => {
   const ignore = content
     .split("\n")
-    .map((line) => line.replace(/#(.*?)$/, "").trim())
-    .filter((line) => !!line);
+    .map(line => line.replace(/#(.*?)$/, "").trim())
+    .filter(line => !!line);
 
   return {
     filepath,
@@ -167,7 +183,7 @@ const readIgnoreConfig = makeStaticFileCache((filepath, content) => {
   };
 });
 
-function makeStaticFileCache<T>(fn: (string, string) => T): (string) => T|null {
+function makeStaticFileCache<T>(fn: (string, string) => T): string => T | null {
   return makeStrongCache((filepath, cache) => {
     if (cache.invalidate(() => fileMtime(filepath)) === null) {
       cache.forever();
@@ -178,7 +194,7 @@ function makeStaticFileCache<T>(fn: (string, string) => T): (string) => T|null {
   });
 }
 
-function fileMtime(filepath: string): number|null {
+function fileMtime(filepath: string): number | null {
   try {
     return +fs.statSync(filepath).mtime;
   } catch (e) {

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

@@ -16,27 +16,47 @@ export function loadConfig(name: string, dirname: string): ConfigFile {
 }
 
 // eslint-disable-next-line no-unused-vars
-export function resolvePlugin(name: string, dirname: string): string|null {
+export function resolvePlugin(name: string, dirname: string): string | null {
   return null;
 }
 
 // eslint-disable-next-line no-unused-vars
-export function resolvePreset(name: string, dirname: string): string|null {
+export function resolvePreset(name: string, dirname: string): string | null {
   return null;
 }
 
-export function loadPlugin(name: string, dirname: string): { filepath: string, value: mixed } {
-  throw new Error(`Cannot load plugin ${name} relative to ${dirname} in a browser`);
+export function loadPlugin(
+  name: string,
+  dirname: string,
+): { filepath: string, value: mixed } {
+  throw new Error(
+    `Cannot load plugin ${name} relative to ${dirname} in a browser`,
+  );
 }
 
-export function loadPreset(name: string, dirname: string): { filepath: string, value: mixed } {
-  throw new Error(`Cannot load preset ${name} relative to ${dirname} in a browser`);
+export function loadPreset(
+  name: string,
+  dirname: string,
+): { filepath: string, value: mixed } {
+  throw new Error(
+    `Cannot load preset ${name} relative to ${dirname} in a browser`,
+  );
 }
 
-export function loadParser(name: string, dirname: string): { filepath: string, value: Function } {
-  throw new Error(`Cannot load parser ${name} relative to ${dirname} in a browser`);
+export function loadParser(
+  name: string,
+  dirname: string,
+): { filepath: string, value: Function } {
+  throw new Error(
+    `Cannot load parser ${name} relative to ${dirname} in a browser`,
+  );
 }
 
-export function loadGenerator(name: string, dirname: string): { filepath: string, value: Function } {
-  throw new Error(`Cannot load generator ${name} relative to ${dirname} in a browser`);
+export function loadGenerator(
+  name: string,
+  dirname: string,
+): { filepath: string, value: Function } {
+  throw new Error(
+    `Cannot load generator ${name} relative to ${dirname} in a browser`,
+  );
 }

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

@@ -5,7 +5,7 @@ import typeof * as indexType from "./index";
 
 // Kind of gross, but essentially asserting that the exports of this module are the same as the
 // exports of index-browser, since this file may be replaced at bundle time with index-browser.
-((({}: any) : $Exact<indexBrowserType>): $Exact<indexType>);
+((({}: any): $Exact<indexBrowserType>): $Exact<indexType>);
 
 export * from "./configuration";
 export * from "./plugins";

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

@@ -15,17 +15,22 @@ const BABEL_PRESET_ORG_RE = /^(@babel[/\/])(?!preset-|[^/\/]+[/\/])/;
 const OTHER_PLUGIN_ORG_RE = /^(@(?!babel[/\/])[^/\/]+[/\/])(?!babel-plugin-|[^/\/]+[/\/])/;
 const OTHER_PRESET_ORG_RE = /^(@(?!babel[/\/])[^/\/]+[/\/])(?!babel-preset-|[^/\/]+[/\/])/;
 
-export function resolvePlugin(name: string, dirname: string): string|null {
+export function resolvePlugin(name: string, dirname: string): string | null {
   return resolveStandardizedName("plugin", name, dirname);
 }
 
-export function resolvePreset(name: string, dirname: string): string|null {
+export function resolvePreset(name: string, dirname: string): string | null {
   return resolveStandardizedName("preset", name, dirname);
 }
 
-export function loadPlugin(name: string, dirname: string): { filepath: string, value: mixed } {
+export function loadPlugin(
+  name: string,
+  dirname: string,
+): { filepath: string, value: mixed } {
   const filepath = resolvePlugin(name, dirname);
-  if (!filepath) throw new Error(`Plugin ${name} not found relative to ${dirname}`);
+  if (!filepath) {
+    throw new Error(`Plugin ${name} not found relative to ${dirname}`);
+  }
 
   return {
     filepath,
@@ -33,9 +38,14 @@ export function loadPlugin(name: string, dirname: string): { filepath: string, v
   };
 }
 
-export function loadPreset(name: string, dirname: string): { filepath: string, value: mixed } {
+export function loadPreset(
+  name: string,
+  dirname: string,
+): { filepath: string, value: mixed } {
   const filepath = resolvePreset(name, dirname);
-  if (!filepath) throw new Error(`Preset ${name} not found relative to ${dirname}`);
+  if (!filepath) {
+    throw new Error(`Preset ${name} not found relative to ${dirname}`);
+  }
 
   return {
     filepath,
@@ -43,16 +53,23 @@ export function loadPreset(name: string, dirname: string): { filepath: string, v
   };
 }
 
-export function loadParser(name: string, dirname: string): { filepath: string, value: Function } {
+export function loadParser(
+  name: string,
+  dirname: string,
+): { filepath: string, value: Function } {
   const filepath = resolve.sync(name, { basedir: dirname });
 
   const mod = requireModule(filepath);
 
   if (!mod) {
-    throw new Error(`Parser ${name} relative to ${dirname} does not export an object`);
+    throw new Error(
+      `Parser ${name} relative to ${dirname} does not export an object`,
+    );
   }
   if (typeof mod.parse !== "function") {
-    throw new Error(`Parser ${name} relative to ${dirname} does not export a .parse function`);
+    throw new Error(
+      `Parser ${name} relative to ${dirname} does not export a .parse function`,
+    );
   }
 
   return {
@@ -61,16 +78,23 @@ export function loadParser(name: string, dirname: string): { filepath: string, v
   };
 }
 
-export function loadGenerator(name: string, dirname: string): { filepath: string, value: Function } {
+export function loadGenerator(
+  name: string,
+  dirname: string,
+): { filepath: string, value: Function } {
   const filepath = resolve.sync(name, { basedir: dirname });
 
   const mod = requireModule(filepath);
 
   if (!mod) {
-    throw new Error(`Generator ${name} relative to ${dirname} does not export an object`);
+    throw new Error(
+      `Generator ${name} relative to ${dirname} does not export an object`,
+    );
   }
   if (typeof mod.print !== "function") {
-    throw new Error(`Generator ${name} relative to ${dirname} does not export a .print function`);
+    throw new Error(
+      `Generator ${name} relative to ${dirname} does not export a .print function`,
+    );
   }
 
   return {
@@ -79,24 +103,39 @@ export function loadGenerator(name: string, dirname: string): { filepath: string
   };
 }
 
-function standardizeName(type: "plugin"|"preset", name: string) {
+function standardizeName(type: "plugin" | "preset", name: string) {
   // Let absolute and relative paths through.
   if (path.isAbsolute(name)) return name;
 
   const isPreset = type === "preset";
 
-  return name
-    // foo -> babel-preset-foo
-    .replace(isPreset ? BABEL_PRESET_PREFIX_RE : BABEL_PLUGIN_PREFIX_RE, `babel-${type}-`)
-    // @babel/es2015 -> @babel/preset-es2015
-    .replace(isPreset ? BABEL_PRESET_ORG_RE : BABEL_PLUGIN_ORG_RE, `$1${type}-`)
-    // @foo/mypreset -> @foo/babel-preset-mypreset
-    .replace(isPreset ? OTHER_PRESET_ORG_RE : OTHER_PLUGIN_ORG_RE, `$1babel-${type}-`)
-    // module:mypreset -> mypreset
-    .replace(EXACT_RE, "");
+  return (
+    name
+      // foo -> babel-preset-foo
+      .replace(
+        isPreset ? BABEL_PRESET_PREFIX_RE : BABEL_PLUGIN_PREFIX_RE,
+        `babel-${type}-`,
+      )
+      // @babel/es2015 -> @babel/preset-es2015
+      .replace(
+        isPreset ? BABEL_PRESET_ORG_RE : BABEL_PLUGIN_ORG_RE,
+        `$1${type}-`,
+      )
+      // @foo/mypreset -> @foo/babel-preset-mypreset
+      .replace(
+        isPreset ? OTHER_PRESET_ORG_RE : OTHER_PLUGIN_ORG_RE,
+        `$1babel-${type}-`,
+      )
+      // module:mypreset -> mypreset
+      .replace(EXACT_RE, "")
+  );
 }
 
-function resolveStandardizedName(type: "plugin"|"preset", name: string, dirname: string = process.cwd()) {
+function resolveStandardizedName(
+  type: "plugin" | "preset",
+  name: string,
+  dirname: string = process.cwd(),
+) {
   const standardizedName = standardizeName(type, name);
 
   try {
@@ -109,7 +148,7 @@ function resolveStandardizedName(type: "plugin"|"preset", name: string, dirname:
       try {
         resolve.sync(name, { basedir: dirname });
         resolvedOriginal = true;
-      } catch (e2) { }
+      } catch (e2) {}
 
       if (resolvedOriginal) {
         // eslint-disable-next-line max-len
@@ -119,9 +158,11 @@ function resolveStandardizedName(type: "plugin"|"preset", name: string, dirname:
 
     let resolvedBabel = false;
     try {
-      resolve.sync(standardizeName(type, "@babel/" + name), { basedir: dirname });
+      resolve.sync(standardizeName(type, "@babel/" + name), {
+        basedir: dirname,
+      });
       resolvedBabel = true;
-    } catch (e2) { }
+    } catch (e2) {}
 
     if (resolvedBabel) {
       // eslint-disable-next-line max-len
@@ -133,7 +174,7 @@ function resolveStandardizedName(type: "plugin"|"preset", name: string, dirname:
     try {
       resolve.sync(standardizeName(oppositeType, name), { basedir: dirname });
       resolvedOppositeType = true;
-    } catch (e2) { }
+    } catch (e2) {}
 
     if (resolvedOppositeType) {
       // eslint-disable-next-line max-len

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

@@ -1,5 +1,3 @@
-// @flow
-
 import * as context from "../index";
 import Plugin from "./plugin";
 import * as messages from "babel-messages";
@@ -11,14 +9,19 @@ import path from "path";
 import traverse from "babel-traverse";
 import clone from "lodash/clone";
 
-import { loadPlugin, loadPreset, loadParser, loadGenerator } from "./loading/files";
+import {
+  loadPlugin,
+  loadPreset,
+  loadParser,
+  loadGenerator,
+} from "./loading/files";
 
 type MergeOptions = {
-  +type: "arguments"|"options"|"preset",
+  +type: "arguments" | "options" | "preset",
   options: {},
   alias: string,
   loc: string,
-  dirname: string
+  dirname: string,
 };
 
 const optionNames = new Set([
@@ -74,8 +77,8 @@ const ALLOWED_PLUGIN_KEYS = new Set([
 
 export default function manageOptions(opts: {}): {
   options: Object,
-  passes: Array<Array<[ Plugin, ?{} ]>>,
-}|null {
+  passes: Array<Array<[Plugin, ?{}]>>,
+} | null {
   return new OptionManager().init(opts);
 }
 
@@ -100,9 +103,12 @@ class OptionManager {
   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 plugins = result.plugins.map(descriptor =>
+      loadPluginDescriptor(descriptor),
+    );
+    const presets = result.presets.map(descriptor =>
+      loadPresetDescriptor(descriptor),
+    );
 
     if (
       config.options.passPerPreset != null &&
@@ -148,7 +154,8 @@ class OptionManager {
       // 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)) {
-        const filename = typeof opts.filename === "string" ? opts.filename : null;
+        const filename =
+          typeof opts.filename === "string" ? opts.filename : null;
         e.message = `[BABEL] ${filename || "unknown"}: ${e.message}`;
       }
 
@@ -160,9 +167,10 @@ class OptionManager {
     // 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.plugins = this.passes[0];
-    opts.presets = this.passes.slice(1)
-      .filter((plugins) => plugins.length > 0)
-      .map((plugins) => ({ plugins }));
+    opts.presets = this.passes
+      .slice(1)
+      .filter(plugins => plugins.length > 0)
+      .map(plugins => ({ plugins }));
 
     if (opts.inputSourceMap) {
       opts.sourceMaps = true;
@@ -199,7 +207,7 @@ class OptionManager {
 }
 
 type BasicDescriptor = {
-  value: {}|Function,
+  value: {} | Function,
   options: ?{},
   dirname: string,
   alias: string,
@@ -209,19 +217,28 @@ type BasicDescriptor = {
 /**
  * Load and validate the given config into a set of options, plugins, and presets.
  */
-function loadConfig(config): {
+function loadConfig(
+  config,
+): {
   options: {},
   plugins: Array<BasicDescriptor>,
   presets: Array<BasicDescriptor>,
 } {
   const options = normalizeOptions(config);
 
-  if (config.options.plugins != null && !Array.isArray(config.options.plugins)) {
+  if (
+    config.options.plugins != null &&
+    !Array.isArray(config.options.plugins)
+  ) {
     throw new Error(".plugins should be an array, null, or undefined");
   }
 
   const plugins = (config.options.plugins || []).map((plugin, index) => {
-    const { filepath, value, options } = normalizePair(plugin, loadPlugin, config.dirname);
+    const { filepath, value, options } = normalizePair(
+      plugin,
+      loadPlugin,
+      config.dirname,
+    );
 
     return {
       alias: filepath || `${config.loc}$${index}`,
@@ -232,12 +249,19 @@ function loadConfig(config): {
     };
   });
 
-  if (config.options.presets != null && !Array.isArray(config.options.presets)) {
+  if (
+    config.options.presets != null &&
+    !Array.isArray(config.options.presets)
+  ) {
     throw new Error(".presets should be an array, null, or undefined");
   }
 
   const presets = (config.options.presets || []).map((preset, index) => {
-    const { filepath, value, options } = normalizePair(preset, loadPreset, config.dirname);
+    const { filepath, value, options } = normalizePair(
+      preset,
+      loadPreset,
+      config.dirname,
+    );
 
     return {
       alias: filepath || `${config.loc}$${index}`,
@@ -255,7 +279,9 @@ function loadConfig(config): {
  * Load a generic plugin/preset from the given descriptor loaded from the config object.
  */
 function loadDescriptor(descriptor, skipOptions) {
-  if (typeof descriptor.value !== "function") return { value: descriptor.value, descriptor };
+  if (typeof descriptor.value !== "function") {
+    return { value: descriptor.value, descriptor };
+  }
 
   const { value, options } = descriptor;
   let item;
@@ -266,7 +292,9 @@ function loadDescriptor(descriptor, skipOptions) {
       item = value(context, options, { dirname: descriptor.dirname });
     }
   } catch (e) {
-    if (descriptor.alias) e.message += ` (While processing: ${JSON.stringify(descriptor.alias)})`;
+    if (descriptor.alias) {
+      e.message += ` (While processing: ${JSON.stringify(descriptor.alias)})`;
+    }
     throw e;
   }
 
@@ -282,26 +310,37 @@ function loadDescriptor(descriptor, skipOptions) {
  */
 const PLUGIN_CACHE = new WeakMap();
 function loadPluginDescriptor(descriptor) {
-  if (descriptor.value instanceof Plugin) return [ descriptor.value, descriptor.options ];
+  if (descriptor.value instanceof Plugin) {
+    return [descriptor.value, descriptor.options];
+  }
 
   let result = PLUGIN_CACHE.get(descriptor.value);
   if (!result) {
-    result = instantiatePlugin(loadDescriptor(descriptor, true /* skipOptions */));
+    result = instantiatePlugin(
+      loadDescriptor(descriptor, true /* skipOptions */),
+    );
     PLUGIN_CACHE.set(descriptor.value, result);
   }
 
-  return [ result, descriptor.options];
+  return [result, descriptor.options];
 }
 
 function instantiatePlugin({ value: pluginObj, descriptor }) {
-  Object.keys(pluginObj).forEach((key) => {
+  Object.keys(pluginObj).forEach(key => {
     if (!ALLOWED_PLUGIN_KEYS.has(key)) {
-      throw new Error(messages.get("pluginInvalidProperty", descriptor.alias, key));
+      throw new Error(
+        messages.get("pluginInvalidProperty", descriptor.alias, key),
+      );
     }
   });
-  if (pluginObj.visitor && (pluginObj.visitor.enter || pluginObj.visitor.exit)) {
-    throw new Error("Plugins aren't allowed to specify catch-all enter/exit handlers. " +
-      "Please target individual nodes.");
+  if (
+    pluginObj.visitor &&
+    (pluginObj.visitor.enter || pluginObj.visitor.exit)
+  ) {
+    throw new Error(
+      "Plugins aren't allowed to specify catch-all enter/exit handlers. " +
+        "Please target individual nodes.",
+    );
   }
 
   const plugin = Object.assign({}, pluginObj, {
@@ -325,8 +364,14 @@ function instantiatePlugin({ value: pluginObj, descriptor }) {
 
     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]);
+    plugin.manipulateOptions = chain(
+      inherits.manipulateOptions,
+      plugin.manipulateOptions,
+    );
+    plugin.visitor = traverse.visitors.merge([
+      inherits.visitor,
+      plugin.visitor,
+    ]);
   }
 
   return new Plugin(plugin, descriptor.alias);
@@ -371,10 +416,18 @@ function normalizeOptions(config) {
   }
 
   if (type === "preset") {
-    if (options.only !== undefined) throw new Error(`${alias}.only is not supported in a preset`);
-    if (options.ignore !== undefined) throw new Error(`${alias}.ignore is not supported in a preset`);
-    if (options.extends !== undefined) throw new Error(`${alias}.extends is not supported in a preset`);
-    if (options.env !== undefined) throw new Error(`${alias}.env is not supported in a preset`);
+    if (options.only !== undefined) {
+      throw new Error(`${alias}.only is not supported in a preset`);
+    }
+    if (options.ignore !== undefined) {
+      throw new Error(`${alias}.ignore is not supported in a preset`);
+    }
+    if (options.extends !== undefined) {
+      throw new Error(`${alias}.extends is not supported in a preset`);
+    }
+    if (options.env !== undefined) {
+      throw new Error(`${alias}.env is not supported in a preset`);
+    }
   }
 
   if (options.sourceMap !== undefined) {
@@ -390,7 +443,10 @@ function normalizeOptions(config) {
     // check for an unknown option
     if (!optionNames.has(key)) {
       if (removed[key]) {
-        throw new ReferenceError(`Using removed Babel 5 option: ${alias}.${key} - ${removed[key].message}`);
+        throw new ReferenceError(
+          `Using removed Babel 5 option: ${alias}.${key} - ${removed[key]
+            .message}`,
+        );
       } else {
         // eslint-disable-next-line max-len
         const unknownOptErr = `Unknown option: ${alias}.${key}. Check out http://babeljs.io/docs/usage/options/ for more information about options.`;
@@ -402,12 +458,21 @@ function normalizeOptions(config) {
 
   if (options.parserOpts && typeof options.parserOpts.parser === "string") {
     options.parserOpts = Object.assign({}, options.parserOpts);
-    options.parserOpts.parser = loadParser(options.parserOpts.parser, config.dirname).value;
+    options.parserOpts.parser = loadParser(
+      options.parserOpts.parser,
+      config.dirname,
+    ).value;
   }
 
-  if (options.generatorOpts && typeof options.generatorOpts.generator === "string") {
+  if (
+    options.generatorOpts &&
+    typeof options.generatorOpts.generator === "string"
+  ) {
     options.generatorOpts = Object.assign({}, options.generatorOpts);
-    options.generatorOpts.generator = loadGenerator(options.generatorOpts.generator, config.dirname).value;
+    options.generatorOpts.generator = loadGenerator(
+      options.generatorOpts.generator,
+      config.dirname,
+    ).value;
   }
 
   delete options.passPerPreset;
@@ -420,16 +485,22 @@ function normalizeOptions(config) {
 /**
  * Given a plugin/preset item, resolve it into a standard format.
  */
-function normalizePair(pair: mixed, resolver, dirname): {
-  filepath: string|null,
-  value: {}|Function,
+function normalizePair(
+  pair: mixed,
+  resolver,
+  dirname,
+): {
+  filepath: string | null,
+  value: {} | Function,
   options: ?{},
 } {
   let options;
   let value = pair;
   if (Array.isArray(pair)) {
     if (pair.length > 2) {
-      throw new Error(`Unexpected extra options ${JSON.stringify(pair.slice(2))}.`);
+      throw new Error(
+        `Unexpected extra options ${JSON.stringify(pair.slice(2))}.`,
+      );
     }
 
     [value, options] = pair;
@@ -437,10 +508,7 @@ function normalizePair(pair: mixed, resolver, dirname): {
 
   let filepath = null;
   if (typeof value === "string") {
-    ({
-      filepath,
-      value,
-    } = resolver(value, dirname));
+    ({ filepath, value } = resolver(value, dirname));
   }
 
   if (!value) {
@@ -456,11 +524,15 @@ function normalizePair(pair: mixed, resolver, dirname): {
   }
 
   if (typeof value !== "object" && typeof value !== "function") {
-    throw new Error(`Unsupported format: ${typeof value}. Expected an object or a function.`);
+    throw new Error(
+      `Unsupported format: ${typeof value}. Expected an object or a function.`,
+    );
   }
 
   if (options != null && typeof options !== "object") {
-    throw new Error("Plugin/Preset options must be an object, null, or undefined");
+    throw new Error(
+      "Plugin/Preset options must be an object, null, or undefined",
+    );
   }
 
   return { filepath, value, options };

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

@@ -5,8 +5,13 @@ export default class Plugin {
     if (plugin.name != null && typeof plugin.name !== "string") {
       throw new Error("Plugin .name must be a string, null, or undefined");
     }
-    if (plugin.manipulateOptions != null && typeof plugin.manipulateOptions !== "function") {
-      throw new Error("Plugin .manipulateOptions must be a function, null, or undefined");
+    if (
+      plugin.manipulateOptions != null &&
+      typeof plugin.manipulateOptions !== "function"
+    ) {
+      throw new Error(
+        "Plugin .manipulateOptions must be a function, null, or undefined",
+      );
     }
     if (plugin.post != null && typeof plugin.post !== "function") {
       throw new Error("Plugin .post must be a function, null, or undefined");

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

@@ -2,52 +2,58 @@
 /* eslint max-len: "off" */
 
 export default {
-  "auxiliaryComment": {
-    "message": "Use `auxiliaryCommentBefore` or `auxiliaryCommentAfter`",
+  auxiliaryComment: {
+    message: "Use `auxiliaryCommentBefore` or `auxiliaryCommentAfter`",
   },
-  "blacklist": {
-    "message": "Put the specific transforms you want in the `plugins` option",
+  blacklist: {
+    message: "Put the specific transforms you want in the `plugins` option",
   },
-  "breakConfig": {
-    "message": "This is not a necessary option in Babel 6",
+  breakConfig: {
+    message: "This is not a necessary option in Babel 6",
   },
-  "experimental": {
-    "message": "Put the specific transforms you want in the `plugins` option",
+  experimental: {
+    message: "Put the specific transforms you want in the `plugins` option",
   },
-  "externalHelpers": {
-    "message": "Use the `external-helpers` plugin instead. Check out http://babeljs.io/docs/plugins/external-helpers/",
+  externalHelpers: {
+    message:
+      "Use the `external-helpers` plugin instead. Check out http://babeljs.io/docs/plugins/external-helpers/",
   },
-  "extra": {
-    "message": "",
+  extra: {
+    message: "",
   },
-  "jsxPragma": {
-    "message": "use the `pragma` option in the `react-jsx` plugin . Check out http://babeljs.io/docs/plugins/transform-react-jsx/",
+  jsxPragma: {
+    message:
+      "use the `pragma` option in the `react-jsx` plugin . Check out http://babeljs.io/docs/plugins/transform-react-jsx/",
   },
   // "keepModuleIdExtensions": {
   //   "message": ""
   // },
-  "loose": {
-    "message": "Specify the `loose` option for the relevant plugin you are using or use a preset that sets the option.",
+  loose: {
+    message:
+      "Specify the `loose` option for the relevant plugin you are using or use a preset that sets the option.",
   },
-  "metadataUsedHelpers": {
-    "message": "Not required anymore as this is enabled by default",
+  metadataUsedHelpers: {
+    message: "Not required anymore as this is enabled by default",
   },
-  "modules": {
-    "message": "Use the corresponding module transform plugin in the `plugins` option. Check out http://babeljs.io/docs/plugins/#modules",
+  modules: {
+    message:
+      "Use the corresponding module transform plugin in the `plugins` option. Check out http://babeljs.io/docs/plugins/#modules",
   },
-  "nonStandard": {
-    "message": "Use the `react-jsx` and `flow-strip-types` plugins to support JSX and Flow. Also check out the react preset http://babeljs.io/docs/plugins/preset-react/",
+  nonStandard: {
+    message:
+      "Use the `react-jsx` and `flow-strip-types` plugins to support JSX and Flow. Also check out the react preset http://babeljs.io/docs/plugins/preset-react/",
   },
-  "optional": {
-    "message": "Put the specific transforms you want in the `plugins` option",
+  optional: {
+    message: "Put the specific transforms you want in the `plugins` option",
   },
-  "sourceMapName": {
-    "message": "Use the `sourceMapTarget` option",
+  sourceMapName: {
+    message: "Use the `sourceMapTarget` option",
   },
-  "stage": {
-    "message": "Check out the corresponding stage-x presets http://babeljs.io/docs/plugins/#presets",
+  stage: {
+    message:
+      "Check out the corresponding stage-x presets http://babeljs.io/docs/plugins/#presets",
   },
-  "whitelist": {
-    "message": "Put the specific transforms you want in the `plugins` option",
+  whitelist: {
+    message: "Put the specific transforms you want in the `plugins` option",
   },
 };

packages/babel-core/src/index.js

@@ -12,7 +12,7 @@ export template from "babel-template";
 
 import loadConfig from "./config";
 
-export function loadOptions(opts): Object|null {
+export function loadOptions(opts): Object | null {
   const config = loadConfig(opts);
 
   return config ? config.options : null;
@@ -41,4 +41,10 @@ export {
  * Recommended set of compilable extensions. Not used in babel-core directly, but meant as
  * as an easy source for tooling making use of babel-core.
  */
-export const DEFAULT_EXTENSIONS = Object.freeze([".js", ".jsx", ".es6", ".es", ".mjs"]);
+export const DEFAULT_EXTENSIONS = Object.freeze([
+  ".js",
+  ".jsx",
+  ".es6",
+  ".es",
+  ".mjs",
+]);

packages/babel-core/src/tools/build-external-helpers.js

@@ -20,17 +20,29 @@ const buildUmdWrapper = template(`
 
 function buildGlobal(namespace, builder) {
   const body = [];
-  const container = t.functionExpression(null, [t.identifier("global")], t.blockStatement(body));
+  const container = t.functionExpression(
+    null,
+    [t.identifier("global")],
+    t.blockStatement(body),
+  );
   const tree = t.program([
-    t.expressionStatement(t.callExpression(container, [helpers.get("selfGlobal")]))]);
-
-  body.push(t.variableDeclaration("var", [
-    t.variableDeclarator(
-      namespace,
-      t.assignmentExpression("=", t.memberExpression(t.identifier("global"), namespace),
-        t.objectExpression([]))
+    t.expressionStatement(
+      t.callExpression(container, [helpers.get("selfGlobal")]),
     ),
-  ]));
+  ]);
+
+  body.push(
+    t.variableDeclaration("var", [
+      t.variableDeclarator(
+        namespace,
+        t.assignmentExpression(
+          "=",
+          t.memberExpression(t.identifier("global"), namespace),
+          t.objectExpression([]),
+        ),
+      ),
+    ]),
+  );
 
   builder(body);
 
@@ -39,9 +51,11 @@ function buildGlobal(namespace, builder) {
 
 function buildUmd(namespace, builder) {
   const body = [];
-  body.push(t.variableDeclaration("var", [
-    t.variableDeclarator(namespace, t.identifier("global")),
-  ]));
+  body.push(
+    t.variableDeclaration("var", [
+      t.variableDeclarator(namespace, t.identifier("global")),
+    ]),
+  );
 
   builder(body);
 
@@ -51,7 +65,7 @@ function buildUmd(namespace, builder) {
       BROWSER_ARGUMENTS: t.assignmentExpression(
         "=",
         t.memberExpression(t.identifier("root"), namespace),
-        t.objectExpression([])
+        t.objectExpression([]),
       ),
       COMMON_ARGUMENTS: t.identifier("exports"),
       AMD_ARGUMENTS: t.arrayExpression([t.stringLiteral("exports")]),
@@ -63,31 +77,39 @@ function buildUmd(namespace, builder) {
 
 function buildVar(namespace, builder) {
   const body = [];
-  body.push(t.variableDeclaration("var", [
-    t.variableDeclarator(namespace, t.objectExpression([])),
-  ]));
+  body.push(
+    t.variableDeclaration("var", [
+      t.variableDeclarator(namespace, t.objectExpression([])),
+    ]),
+  );
   builder(body);
   body.push(t.expressionStatement(namespace));
   return t.program(body);
 }
 
 function buildHelpers(body, namespace, whitelist) {
-  helpers.list.forEach(function (name) {
+  helpers.list.forEach(function(name) {
     if (whitelist && whitelist.indexOf(name) < 0) return;
 
     const key = t.identifier(name);
-    body.push(t.expressionStatement(
-      t.assignmentExpression("=", t.memberExpression(namespace, key), helpers.get(name))
-    ));
+    body.push(
+      t.expressionStatement(
+        t.assignmentExpression(
+          "=",
+          t.memberExpression(namespace, key),
+          helpers.get(name),
+        ),
+      ),
+    );
   });
 }
-export default function (
+export default function(
   whitelist?: Array<string>,
   outputType: "global" | "umd" | "var" = "global",
 ) {
   const namespace = t.identifier("babelHelpers");
 
-  const builder = function (body) {
+  const builder = function(body) {
     return buildHelpers(body, namespace, whitelist);
   };
 

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

@@ -7,7 +7,7 @@ import PluginPass from "../plugin-pass";
 import { NodePath, Hub, Scope } from "babel-traverse";
 import sourceMap from "source-map";
 import generate from "babel-generator";
-import codeFrame from "babel-code-frame";
+import { codeFrameColumns } from "babel-code-frame";
 import traverse from "babel-traverse";
 import Store from "../store";
 import { parse } from "babylon";
@@ -45,7 +45,7 @@ export default class File extends Store {
       // passed babel-core's export object, which loads this file, and this 'loadConfig' loading plugins.
       INTERNAL_PLUGINS = loadConfig({
         babelrc: false,
-        plugins: [ blockHoistPlugin ],
+        plugins: [blockHoistPlugin],
       }).passes[0];
     }
 
@@ -61,7 +61,7 @@ export default class File extends Store {
     };
 
     for (const pluginPairs of passes) {
-      for (const [ plugin ] of pluginPairs) {
+      for (const [plugin] of pluginPairs) {
         if (plugin.manipulateOptions) {
           plugin.manipulateOptions(this.opts, this.parserOpts, this);
         }
@@ -150,7 +150,7 @@ export default class File extends Store {
 
     if (opts.sourceRoot != null) {
       // remove sourceRoot from filename
-      const sourceRootRegEx = new RegExp("^" + opts.sourceRoot + "\/?");
+      const sourceRootRegEx = new RegExp("^" + opts.sourceRoot + "/?");
       filenameRelative = filenameRelative.replace(sourceRootRegEx, "");
     }
 
@@ -172,17 +172,40 @@ export default class File extends Store {
 
   resolveModuleSource(source: string): string {
     const resolveModuleSource = this.opts.resolveModuleSource;
-    if (resolveModuleSource) source = resolveModuleSource(source, this.opts.filename);
+    if (resolveModuleSource) {
+      source = resolveModuleSource(source, this.opts.filename);
+    }
     return source;
   }
 
-  addImport(source: string, imported: string, name?: string = imported): Object {
+  addImport(
+    source: string,
+    imported?: string = "",
+    name?: string = imported,
+  ): Object | null {
+    const prependDeclaration = (
+      specifiers: Array<BabelNodeImportSpecifier>,
+    ): void => {
+      const declar = t.importDeclaration(specifiers, t.stringLiteral(source));
+      declar._blockHoist = 3;
+
+      this.path.unshiftContainer("body", declar);
+    };
+
+    // import "module-name";
+    if (!imported) {
+      prependDeclaration([]);
+      return null;
+    }
+
     const alias = `${source}:${imported}`;
     let id = this.dynamicImportIds[alias];
 
     if (!id) {
       source = this.resolveModuleSource(source);
-      id = this.dynamicImportIds[alias] = this.scope.generateUidIdentifier(name);
+      id = this.dynamicImportIds[alias] = this.scope.generateUidIdentifier(
+        name,
+      );
 
       const specifiers = [];
 
@@ -194,10 +217,7 @@ export default class File extends Store {
         specifiers.push(t.importSpecifier(id, t.identifier(imported)));
       }
 
-      const declar = t.importDeclaration(specifiers, t.stringLiteral(source));
-      declar._blockHoist = 3;
-
-      this.path.unshiftContainer("body", declar);
+      prependDeclaration(specifiers);
     }
 
     return id;
@@ -222,11 +242,12 @@ export default class File extends Store {
     }
 
     const ref = getHelper(name);
-    const uid = this.declarations[name] = this.scope.generateUidIdentifier(name);
+    const uid = (this.declarations[name] = this.scope.generateUidIdentifier(
+      name,
+    ));
 
     if (t.isFunctionExpression(ref) && !ref.id) {
       ref.body._compact = true;
-      ref._generated = true;
       ref.id = uid;
       ref.type = "FunctionDeclaration";
       this.path.unshiftContainer("body", ref);
@@ -257,7 +278,9 @@ export default class File extends Store {
     const declar = this.declarations[name];
     if (declar) return declar;
 
-    const uid = this.declarations[name] = this.scope.generateUidIdentifier("templateObject");
+    const uid = (this.declarations[name] = this.scope.generateUidIdentifier(
+      "templateObject",
+    ));
 
     const helperId = this.addHelper(helperName);
     const init = t.callExpression(helperId, [strings, raw]);
@@ -270,7 +293,11 @@ export default class File extends Store {
     return uid;
   }
 
-  buildCodeFrameError(node: Object, msg: string, Error: typeof Error = SyntaxError): Error {
+  buildCodeFrameError(
+    node: Object,
+    msg: string,
+    Error: typeof Error = SyntaxError,
+  ): Error {
     const loc = node && (node.loc || node._loc);
 
     const err = new Error(msg);
@@ -280,7 +307,8 @@ export default class File extends Store {
     } else {
       traverse(node, errorVisitor, this.scope, err);
 
-      err.message += " (This is an error on an internal node. Probably an internal error";
+      err.message +=
+        " (This is an error on an internal node. Probably an internal error";
 
       if (err.loc) {
         err.message += ". Location has been estimated.";
@@ -308,7 +336,7 @@ export default class File extends Store {
       // single source file to a single output file.
       const source = outputMapConsumer.sources[0];
 
-      inputMapConsumer.eachMapping(function (mapping) {
+      inputMapConsumer.eachMapping(function(mapping) {
         const generatedPosition = outputMapConsumer.generatedPositionFor({
           line: mapping.generatedLine,
           column: mapping.generatedColumn,
@@ -318,10 +346,13 @@ export default class File extends Store {
           mergedGenerator.addMapping({
             source: mapping.source,
 
-            original: mapping.source == null ? null : {
-              line: mapping.originalLine,
-              column: mapping.originalColumn,
-            },
+            original:
+              mapping.source == null
+                ? null
+                : {
+                    line: mapping.originalLine,
+                    column: mapping.originalColumn,
+                  },
 
             generated: generatedPosition,
           });
@@ -385,15 +416,15 @@ export default class File extends Store {
       const passes = [];
       const visitors = [];
 
-      for (const [ plugin, pluginOpts ] of pluginPairs.concat(INTERNAL_PLUGINS)) {
+      for (const [plugin, pluginOpts] of pluginPairs.concat(INTERNAL_PLUGINS)) {
         const pass = new PluginPass(this, plugin.key, pluginOpts);
 
-        passPairs.push([ plugin, pass ]);
+        passPairs.push([plugin, pass]);
         passes.push(pass);
         visitors.push(plugin.visitor);
       }
 
-      for (const [ plugin, pass ] of passPairs) {
+      for (const [plugin, pass] of passPairs) {
         const fn = plugin.pre;
         if (fn) fn.call(pass, this);
       }
@@ -401,16 +432,19 @@ export default class File extends Store {
       debug(this.opts, "Start transform traverse");
 
       // merge all plugin visitors into a single visitor
-      const visitor = traverse.visitors.merge(visitors, passes, this.opts.wrapPluginVisitorMethod);
+      const visitor = traverse.visitors.merge(
+        visitors,
+        passes,
+        this.opts.wrapPluginVisitorMethod,
+      );
       traverse(this.ast, visitor, this.scope);
 
       debug(this.opts, "End transform traverse");
 
-      for (const [ plugin, pass ] of passPairs) {
+      for (const [plugin, pass] of passPairs) {
         const fn = plugin.post;
         if (fn) fn.call(pass, this);
       }
-
     }
 
     return this.generate();
@@ -428,11 +462,17 @@ export default class File extends Store {
         err._babel = true;
       }
 
-      let message = err.message = `${this.opts.filename}: ${err.message}`;
+      let message = (err.message = `${this.opts.filename}: ${err.message}`);
 
       const loc = err.loc;
       if (loc) {
-        err.codeFrame = codeFrame(code, loc.line, loc.column + 1, this.opts);
+        const location = {
+          start: {
+            line: loc.line,
+            column: loc.column + 1,
+          },
+        };
+        err.codeFrame = codeFrameColumns(code, location, this.opts);
         message += "\n" + err.codeFrame;
       }
 
@@ -524,8 +564,11 @@ export default class File extends Store {
 
     debug(this.opts, "Generation start");
 
-    const _result = gen(ast, opts.generatorOpts ? Object.assign(opts, opts.generatorOpts) : opts,
-      this.code);
+    const _result = gen(
+      ast,
+      opts.generatorOpts ? Object.assign(opts, opts.generatorOpts) : opts,
+      this.code,
+    );
     result.code = _result.code;
     result.map = _result.map;
 

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

@@ -5,7 +5,11 @@ import * as t from "babel-types";
 import File from "./file";
 import loadConfig from "../config";
 
-export function analyse(code: string, opts: Object = {}, visitor?: Object): ?BabelFileMetadata {
+export function analyse(
+  code: string,
+  opts: Object = {},
+  visitor?: Object,
+): ?BabelFileMetadata {
   opts.code = false;
   if (visitor) {
     opts.plugins = opts.plugins || [];
@@ -19,14 +23,18 @@ export function transform(code: string, opts?: Object): BabelFileResult {
   if (config === null) return null;
 
   const file = new File(config);
-  return file.wrap(code, function () {
+  return file.wrap(code, function() {
     file.addCode(code);
     file.parseCode(code);
     return file.transform();
   });
 }
 
-export function transformFromAst(ast: Object, code: string, opts: Object): BabelFileResult {
+export function transformFromAst(
+  ast: Object,
+  code: string,
+  opts: Object,
+): BabelFileResult {
   const config = loadConfig(opts);
   if (config === null) return null;
 
@@ -37,14 +45,18 @@ export function transformFromAst(ast: Object, code: string, opts: Object): Babel
   }
 
   const file = new File(config);
-  return file.wrap(code, function () {
+  return file.wrap(code, function() {
     file.addCode(code);
     file.addAst(ast);
     return file.transform();
   });
 }
 
-export function transformFile(filename: string, opts?: Object, callback: Function) {
+export function transformFile(
+  filename: string,
+  opts?: Object,
+  callback: Function,
+) {
   if (typeof opts === "function") {
     callback = opts;
     opts = {};
@@ -54,13 +66,13 @@ export function transformFile(filename: string, opts?: Object, callback: Functio
   const config = loadConfig(opts);
   if (config === null) return callback(null, null);
 
-  fs.readFile(filename, function (err, code) {
+  fs.readFile(filename, function(err, code) {
     let result;
 
     if (!err) {
       try {
         const file = new File(config);
-        result = file.wrap(code, function () {
+        result = file.wrap(code, function() {
           file.addCode(code);
           file.parseCode(code);
           return file.transform();
@@ -78,7 +90,10 @@ export function transformFile(filename: string, opts?: Object, callback: Functio
   });
 }
 
-export function transformFileSync(filename: string, opts?: Object = {}): string {
+export function transformFileSync(
+  filename: string,
+  opts?: Object = {},
+): string {
   opts.filename = filename;
   const config = loadConfig(opts);
   if (config === null) return null;
@@ -86,7 +101,7 @@ export function transformFileSync(filename: string, opts?: Object = {}): string
   const code = fs.readFileSync(filename, "utf8");
   const file = new File(config);
 
-  return file.wrap(code, function () {
+  return file.wrap(code, function() {
     file.addCode(code);
     file.parseCode(code);
     return file.transform();

packages/babel-core/test/api.js

@@ -17,7 +17,7 @@ function assertNotIgnored(result) {
 // shim
 function transformAsync(code, opts) {
   return {
-    then: function (resolve) {
+    then: function(resolve) {
       resolve(babel.transform(code, opts));
     },
   };
@@ -55,11 +55,14 @@ describe("parser and generator options", function() {
   it("experimental syntax", function() {
     const experimental = "var a: number = 1;";
 
-    assert.deepEqual(newTransform(experimental).ast, babel.transform(experimental, {
-      parserOpts: {
-        plugins: ["flow"],
-      },
-    }).ast);
+    assert.deepEqual(
+      newTransform(experimental).ast,
+      babel.transform(experimental, {
+        parserOpts: {
+          plugins: ["flow"],
+        },
+      }).ast,
+    );
     assert.equal(newTransform(experimental).code, experimental);
 
     function newTransformWithPlugins(string) {
@@ -74,126 +77,158 @@ describe("parser and generator options", function() {
       });
     }
 
-    assert.deepEqual(newTransformWithPlugins(experimental).ast, babel.transform(experimental, {
-      parserOpts: {
-        plugins: ["flow"],
-      },
-    }).ast);
+    assert.deepEqual(
+      newTransformWithPlugins(experimental).ast,
+      babel.transform(experimental, {
+        parserOpts: {
+          plugins: ["flow"],
+        },
+      }).ast,
+    );
     assert.equal(newTransformWithPlugins(experimental).code, experimental);
   });
 
   it("other options", function() {
     const experimental = "if (true) {\n  import a from 'a';\n}";
 
-    assert.notEqual(newTransform(experimental).ast, babel.transform(experimental, {
-      parserOpts: {
-        allowImportExportEverywhere: true,
-      },
-    }).ast);
+    assert.notEqual(
+      newTransform(experimental).ast,
+      babel.transform(experimental, {
+        parserOpts: {
+          allowImportExportEverywhere: true,
+        },
+      }).ast,
+    );
     assert.equal(newTransform(experimental).code, experimental);
   });
 });
 
-describe("api", function () {
-  it("analyze", function () {
+describe("api", function() {
+  it("analyze", function() {
     assert.equal(babel.analyse("foobar;").marked.length, 0);
 
-    assert.equal(babel.analyse("foobar;", {
-      plugins: [new Plugin({
-        visitor: {
-          Program: function (path) {
+    assert.equal(
+      babel.analyse("foobar;", {
+        plugins: [
+          new Plugin({
+            visitor: {
+              Program: function(path) {
+                path.mark("category", "foobar");
+              },
+            },
+          }),
+        ],
+      }).marked[0].message,
+      "foobar",
+    );
+
+    assert.equal(
+      babel.analyse(
+        "foobar;",
+        {},
+        {
+          Program: function(path) {
             path.mark("category", "foobar");
           },
         },
-      })],
-    }).marked[0].message, "foobar");
-
-    assert.equal(babel.analyse("foobar;", {}, {
-      Program: function (path) {
-        path.mark("category", "foobar");
-      },
-    }).marked[0].message, "foobar");
-  });
-
-  it("exposes the resolvePlugin method", function() {
-    assert.throws(() => babel.resolvePlugin("nonexistent-plugin"),
-      /Cannot find module 'babel-plugin-nonexistent-plugin'/);
-  });
-
-  it("exposes the resolvePreset method", function() {
-    assert.throws(() => babel.resolvePreset("nonexistent-preset"),
-      /Cannot find module 'babel-preset-nonexistent-preset'/);
-  });
-
-  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();
-    });
-  });
-
-  it("transformFileSync", function () {
-    assert.equal(babel.transformFileSync(__dirname + "/fixtures/api/file.js", {
-      babelrc: false,
-    }).code, "foo();");
-  });
-
-  it("options throw on falsy true", function () {
-    return assert.throws(
-      function () {
-        babel.transform("", {
-          plugins: [__dirname + "/../../babel-plugin-syntax-jsx", false],
-        });
-      },
-      /Error: \[BABEL\] unknown: Unexpected falsy value: false/
+      ).marked[0].message,
+      "foobar",
     );
   });
 
-  it("options merge backwards", function () {
+  it("exposes the resolvePlugin method", function() {
+    assert.throws(
+      () => babel.resolvePlugin("nonexistent-plugin"),
+      /Cannot find module 'babel-plugin-nonexistent-plugin'/,
+    );
+  });
+
+  it("exposes the resolvePreset method", function() {
+    assert.throws(
+      () => babel.resolvePreset("nonexistent-preset"),
+      /Cannot find module 'babel-preset-nonexistent-preset'/,
+    );
+  });
+
+  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();
+      },
+    );
+  });
+
+  it("transformFileSync", function() {
+    assert.equal(
+      babel.transformFileSync(__dirname + "/fixtures/api/file.js", {
+        babelrc: false,
+      }).code,
+      "foo();",
+    );
+  });
+
+  it("options throw on falsy true", function() {
+    return assert.throws(function() {
+      babel.transform("", {
+        plugins: [__dirname + "/../../babel-plugin-syntax-jsx", false],
+      });
+    }, /Error: \[BABEL\] unknown: Unexpected falsy value: false/);
+  });
+
+  it("options merge backwards", function() {
     return transformAsync("", {
       presets: [__dirname + "/../../babel-preset-es2015"],
       plugins: [__dirname + "/../../babel-plugin-syntax-jsx"],
-    }).then(function (result) {
-      assert.ok(result.options.plugins[0][0].manipulateOptions.toString().indexOf("jsx") >= 0);
+    }).then(function(result) {
+      assert.ok(
+        result.options.plugins[0][0].manipulateOptions
+          .toString()
+          .indexOf("jsx") >= 0,
+      );
     });
   });
 
-  it("option wrapPluginVisitorMethod", function () {
+  it("option wrapPluginVisitorMethod", function() {
     let calledRaw = 0;
     let calledIntercept = 0;
 
     babel.transform("function foo() { bar(foobar); }", {
-      wrapPluginVisitorMethod: function (pluginAlias, visitorType, callback) {
+      wrapPluginVisitorMethod: function(pluginAlias, visitorType, callback) {
         if (pluginAlias !== "foobar") {
           return callback;
         }
 
         assert.equal(visitorType, "enter");
 
-        return function () {
+        return function() {
           calledIntercept++;
           return callback.apply(this, arguments);
         };
       },
 
-      plugins: [new Plugin({
-        name: "foobar",
-        visitor: {
-          "Program|Identifier": function () {
-            calledRaw++;
+      plugins: [
+        new Plugin({
+          name: "foobar",
+          visitor: {
+            "Program|Identifier": function() {
+              calledRaw++;
+            },
           },
-        },
-      })],
+        }),
+      ],
     });
 
     assert.equal(calledRaw, 4);
     assert.equal(calledIntercept, 4);
   });
 
-  it("pass per preset", function () {
+  it("pass per preset", function() {
     let aliasBaseType = null;
 
     function execTest(passPerPreset) {
@@ -201,13 +236,15 @@ describe("api", function () {
         passPerPreset: passPerPreset,
         presets: [
           // First preset with our plugin, "before"
-          function () {
+          function() {
             return {
               plugins: [
                 new Plugin({
                   visitor: {
-                    Function: function (path) {
-                      const alias = path.scope.getProgramParent().path.get("body")[0].node;
+                    Function: function(path) {
+                      const alias = path.scope
+                        .getProgramParent()
+                        .path.get("body")[0].node;
                       if (!babel.types.isTypeAlias(alias)) return;
 
                       // In case of `passPerPreset` being `false`, the
@@ -230,11 +267,12 @@ describe("api", function () {
           require(__dirname + "/../../babel-preset-es2015"),
 
           // Third preset for Flow.
-          function () {
+          function() {
             return {
               plugins: [
                 require(__dirname + "/../../babel-plugin-syntax-flow"),
-                require(__dirname + "/../../babel-plugin-transform-flow-strip-types"),
+                require(__dirname +
+                  "/../../babel-plugin-transform-flow-strip-types"),
               ],
             };
           },
@@ -248,13 +286,16 @@ describe("api", function () {
 
     assert.equal(aliasBaseType, "NumberTypeAnnotation");
 
-    assert.deepEqual([
-      "\"use strict\";",
-      "",
-      "var x = function x(y) {",
-      "  return y;",
-      "};",
-    ].join("\n"), result.code);
+    assert.deepEqual(
+      [
+        '"use strict";',
+        "",
+        "var x = function x(y) {",
+        "  return y;",
+        "};",
+      ].join("\n"),
+      result.code,
+    );
 
     // 2. passPerPreset: false
 
@@ -264,14 +305,16 @@ describe("api", function () {
 
     assert.equal(aliasBaseType, null);
 
-    assert.deepEqual([
-      "\"use strict\";",
-      "",
-      "var x = function x(y) {",
-      "  return y;",
-      "};",
-    ].join("\n"), result.code);
-
+    assert.deepEqual(
+      [
+        '"use strict";',
+        "",
+        "var x = function x(y) {",
+        "  return y;",
+        "};",
+      ].join("\n"),
+      result.code,
+    );
   });
 
   it("complex plugin and preset ordering", function() {
@@ -279,7 +322,10 @@ describe("api", function () {
       return {
         visitor: {
           Program(path) {
-            path.pushContainer("body", babel.types.expressionStatement(babel.types.identifier(str)));
+            path.pushContainer(
+              "body",
+              babel.types.expressionStatement(babel.types.identifier(str)),
+            );
           },
         },
       };
@@ -290,288 +336,345 @@ describe("api", function () {
     }
 
     const result = babel.transform("", {
-      filename: path.join(__dirname, "fixtures", "config", "complex-plugin-config", "file.js"),
-      presets: [
-        pushPreset("argone"),
-        pushPreset("argtwo"),
-      ],
+      filename: path.join(
+        __dirname,
+        "fixtures",
+        "config",
+        "complex-plugin-config",
+        "file.js",
+      ),
+      presets: [pushPreset("argone"), pushPreset("argtwo")],
       env: {
         development: {
           passPerPreset: true,
-          presets: [
-            pushPreset("argthree"),
-            pushPreset("argfour"),
-          ],
+          presets: [pushPreset("argthree"), pushPreset("argfour")],
           env: {
             development: {
               passPerPreset: true,
-              presets: [
-                pushPreset("argfive"),
-                pushPreset("argsix"),
-              ],
+              presets: [pushPreset("argfive"), pushPreset("argsix")],
             },
           },
         },
       },
     });
 
-    assert.equal(result.code, [
-      "argtwo;",
-      "argone;",
-      "eleven;",
-      "twelve;",
-      "one;",
-      "two;",
-      "five;",
-      "six;",
-      "three;",
-      "four;",
-      "seventeen;",
-      "eighteen;",
-      "nineteen;",
-      "twenty;",
-      "thirteen;",
-      "fourteen;",
-      "fifteen;",
-      "sixteen;",
-      "argfive;",
-      "argsix;",
-      "argthree;",
-      "argfour;",
-      "seven;",
-      "eight;",
-      "nine;",
-      "ten;",
-    ].join("\n"));
+    assert.equal(
+      result.code,
+      [
+        "argtwo;",
+        "argone;",
+        "eleven;",
+        "twelve;",
+        "one;",
+        "two;",
+        "five;",
+        "six;",
+        "three;",
+        "four;",
+        "seventeen;",
+        "eighteen;",
+        "nineteen;",
+        "twenty;",
+        "thirteen;",
+        "fourteen;",
+        "fifteen;",
+        "sixteen;",
+        "argfive;",
+        "argsix;",
+        "argthree;",
+        "argfour;",
+        "seven;",
+        "eight;",
+        "nine;",
+        "ten;",
+      ].join("\n"),
+    );
   });
 
-  it("source map merging", function () {
-    const result = babel.transform([
-      /* eslint-disable max-len */
-      "function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError(\"Cannot call a class as a function\"); } }",
-      "",
-      "let Foo = function Foo() {",
-      "  _classCallCheck(this, Foo);",
-      "};",
-      "",
-      "//# sourceMappingURL=data:application/json;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZG91dCJdLCJuYW1lcyI6W10sIm1hcHBpbmdzIjoiOztJQUFNLEdBQUcsWUFBSCxHQUFHO3dCQUFILEdBQUciLCJmaWxlIjoidW5kZWZpbmVkIiwic291cmNlc0NvbnRlbnQiOlsiY2xhc3MgRm9vIHt9XG4iXX0=",
-      /* eslint-enable max-len */
-    ].join("\n"), {
-      sourceMap: true,
-    });
+  it("source map merging", function() {
+    const result = babel.transform(
+      [
+        /* eslint-disable max-len */
+        'function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }',
+        "",
+        "let Foo = function Foo() {",
+        "  _classCallCheck(this, Foo);",
+        "};",
+        "",
+        "//# sourceMappingURL=data:application/json;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZG91dCJdLCJuYW1lcyI6W10sIm1hcHBpbmdzIjoiOztJQUFNLEdBQUcsWUFBSCxHQUFHO3dCQUFILEdBQUciLCJmaWxlIjoidW5kZWZpbmVkIiwic291cmNlc0NvbnRlbnQiOlsiY2xhc3MgRm9vIHt9XG4iXX0=",
+        /* eslint-enable max-len */
+      ].join("\n"),
+      {
+        sourceMap: true,
+      },
+    );
 
-    assert.deepEqual([
-      "function _classCallCheck(instance, Constructor) {",
-      "  if (!(instance instanceof Constructor)) {",
-      "    throw new TypeError(\"Cannot call a class as a function\");",
-      "  }",
-      "}",
-      "",
-      "let Foo = function Foo() {",
-      "  _classCallCheck(this, Foo);",
-      "};",
-    ].join("\n"), result.code);
+    assert.deepEqual(
+      [
+        "function _classCallCheck(instance, Constructor) {",
+        "  if (!(instance instanceof Constructor)) {",
+        '    throw new TypeError("Cannot call a class as a function");',
+        "  }",
+        "}",
+        "",
+        "let Foo = function Foo() {",
+        "  _classCallCheck(this, Foo);",
+        "};",
+      ].join("\n"),
+      result.code,
+    );
 
     const consumer = new sourceMap.SourceMapConsumer(result.map);
 
-    assert.deepEqual(consumer.originalPositionFor({
-      line: 7,
-      column: 4,
-    }), {
-      name: null,
-      source: "stdout",
-      line: 1,
-      column: 6,
-    });
+    assert.deepEqual(
+      consumer.originalPositionFor({
+        line: 7,
+        column: 4,
+      }),
+      {
+        name: null,
+        source: "stdout",
+        line: 1,
+        column: 6,
+      },
+    );
   });
 
-  it("code option false", function () {
-    return transformAsync("foo('bar');", { code: false }).then(function (result) {
+  it("code option false", function() {
+    return transformAsync("foo('bar');", { code: false }).then(function(
+      result,
+    ) {
       assert.ok(!result.code);
     });
   });
 
-  it("ast option false", function () {
-    return transformAsync("foo('bar');", { ast: false }).then(function (result) {
+  it("ast option false", function() {
+    return transformAsync("foo('bar');", { ast: false }).then(function(result) {
       assert.ok(!result.ast);
     });
   });
 
-  it("auxiliaryComment option", function () {
+  it("auxiliaryComment option", function() {
     return transformAsync("class Foo {}", {
       auxiliaryCommentBefore: "before",
       auxiliaryCommentAfter: "after",
-      plugins: [function (babel) {
-        const t = babel.types;
-        return {
-          visitor: {
-            Program: function (path) {
-              path.unshiftContainer("body", t.expressionStatement(t.identifier("start")));
-              path.pushContainer("body", t.expressionStatement(t.identifier("end")));
+      plugins: [
+        function(babel) {
+          const t = babel.types;
+          return {
+            visitor: {
+              Program: function(path) {
+                path.unshiftContainer(
+                  "body",
+                  t.expressionStatement(t.identifier("start")),
+                );
+                path.pushContainer(
+                  "body",
+                  t.expressionStatement(t.identifier("end")),
+                );
+              },
             },
-          },
-        };
-      }],
-    }).then(function (result) {
-      assert.equal(result.code,
-        "/*before*/start;\n/*after*/class Foo {}\n/*before*/end;\n/*after*/");
+          };
+        },
+      ],
+    }).then(function(result) {
+      assert.equal(
+        result.code,
+        "/*before*/\nstart;\n\n/*after*/\nclass Foo {}\n\n/*before*/\nend;\n\n/*after*/",
+      );
     });
   });
 
-  it("modules metadata", function () {
+  it("modules metadata", function() {
     return Promise.all([
       // eslint-disable-next-line max-len
-      transformAsync("import { externalName as localName } from \"external\";").then(function (result) {
+      transformAsync(
+        'import { externalName as localName } from "external";',
+      ).then(function(result) {
         assert.deepEqual(result.metadata.modules.imports[0], {
           source: "external",
           imported: ["externalName"],
-          specifiers: [{
-            kind: "named",
-            imported: "externalName",
-            local: "localName",
-          }],
+          specifiers: [
+            {
+              kind: "named",
+              imported: "externalName",
+              local: "localName",
+            },
+          ],
         });
       }),
 
-      transformAsync("import * as localName2 from \"external\";").then(function (result) {
+      transformAsync('import * as localName2 from "external";').then(function(
+        result,
+      ) {
         assert.deepEqual(result.metadata.modules.imports[0], {
           source: "external",
           imported: ["*"],
-          specifiers: [{
-            kind: "namespace",
-            local: "localName2",
-          }],
+          specifiers: [
+            {
+              kind: "namespace",
+              local: "localName2",
+            },
+          ],
         });
       }),
 
-      transformAsync("import localName3 from \"external\";").then(function (result) {
+      transformAsync('import localName3 from "external";').then(function(
+        result,
+      ) {
         assert.deepEqual(result.metadata.modules.imports[0], {
           source: "external",
           imported: ["default"],
-          specifiers: [{
-            kind: "named",
-            imported: "default",
-            local: "localName3",
-          }],
+          specifiers: [
+            {
+              kind: "named",
+              imported: "default",
+              local: "localName3",
+            },
+          ],
         });
       }),
 
-      transformAsync("import localName from \"./array\";", {
+      transformAsync('import localName from "./array";', {
         resolveModuleSource: function() {
           return "override-source";
         },
-      }).then(function (result) {
+      }).then(function(result) {
         assert.deepEqual(result.metadata.modules.imports, [
           {
             source: "override-source",
             imported: ["default"],
             specifiers: [
               {
-                "kind": "named",
-                "imported": "default",
-                "local": "localName",
+                kind: "named",
+                imported: "default",
+                local: "localName",
               },
             ],
           },
         ]);
       }),
 
-      transformAsync("export * as externalName1 from \"external\";", {
+      transformAsync('export * as externalName1 from "external";', {
         plugins: [require("../../babel-plugin-syntax-export-extensions")],
-      }).then(function (result) {
+      }).then(function(result) {
         assert.deepEqual(result.metadata.modules.exports, {
           exported: ["externalName1"],
-          specifiers: [{
-            kind: "external-namespace",
-            exported: "externalName1",
-            source: "external",
-          }],
+          specifiers: [
+            {
+              kind: "external-namespace",
+              exported: "externalName1",
+              source: "external",
+            },
+          ],
         });
       }),
 
-      transformAsync("export externalName2 from \"external\";", {
+      transformAsync('export externalName2 from "external";', {
         plugins: [require("../../babel-plugin-syntax-export-extensions")],
-      }).then(function (result) {
+      }).then(function(result) {
         assert.deepEqual(result.metadata.modules.exports, {
           exported: ["externalName2"],
-          specifiers: [{
-            kind: "external",
-            local: "externalName2",
-            exported: "externalName2",
-            source: "external",
-          }],
+          specifiers: [
+            {
+              kind: "external",
+              local: "externalName2",
+              exported: "externalName2",
+              source: "external",
+            },
+          ],
         });
       }),
 
-      transformAsync("export function namedFunction() {}").then(function (result) {
+      transformAsync("export function namedFunction() {}").then(function(
+        result,
+      ) {
         assert.deepEqual(result.metadata.modules.exports, {
           exported: ["namedFunction"],
-          specifiers: [{
-            kind: "local",
-            local: "namedFunction",
-            exported: "namedFunction",
-          }],
+          specifiers: [
+            {
+              kind: "local",
+              local: "namedFunction",
+              exported: "namedFunction",
+            },
+          ],
         });
       }),
 
-      transformAsync("export var foo = \"bar\";").then(function (result) {
+      transformAsync('export var foo = "bar";').then(function(result) {
         assert.deepEqual(result.metadata.modules.exports, {
-          "exported": ["foo"],
-          specifiers: [{
-            kind: "local",
-            local: "foo",
-            exported: "foo",
-          }],
+          exported: ["foo"],
+          specifiers: [
+            {
+              kind: "local",
+              local: "foo",
+              exported: "foo",
+            },
+          ],
         });
       }),
 
-      transformAsync("export { localName as externalName3 };").then(function (result) {
+      transformAsync("export { localName as externalName3 };").then(function(
+        result,
+      ) {
         assert.deepEqual(result.metadata.modules.exports, {
           exported: ["externalName3"],
-          specifiers: [{
-            kind: "local",
-            local: "localName",
-            exported: "externalName3",
-          }],
+          specifiers: [
+            {
+              kind: "local",
+              local: "localName",
+              exported: "externalName3",
+            },
+          ],
         });
       }),
 
-      transformAsync("export { externalName4 } from \"external\";").then(function (result) {
+      transformAsync('export { externalName4 } from "external";').then(function(
+        result,
+      ) {
         assert.deepEqual(result.metadata.modules.exports, {
           exported: ["externalName4"],
-          specifiers: [{
-            kind: "external",
-            local: "externalName4",
-            exported: "externalName4",
-            source: "external",
-          }],
+          specifiers: [
+            {
+              kind: "external",
+              local: "externalName4",
+              exported: "externalName4",
+              source: "external",
+            },
+          ],
         });
       }),
 
-      transformAsync("export * from \"external\";").then(function (result) {
+      transformAsync('export * from "external";').then(function(result) {
         assert.deepEqual(result.metadata.modules.exports, {
           exported: [],
-          specifiers: [{
-            kind: "external-all",
-            source: "external",
-          }],
+          specifiers: [
+            {
+              kind: "external-all",
+              source: "external",
+            },
+          ],
         });
       }),
 
-      transformAsync("export default function defaultFunction() {}").then(function (result) {
+      transformAsync(
+        "export default function defaultFunction() {}",
+      ).then(function(result) {
         assert.deepEqual(result.metadata.modules.exports, {
           exported: ["defaultFunction"],
-          specifiers: [{
-            kind: "local",
-            local: "defaultFunction",
-            exported: "default",
-          }],
+          specifiers: [
+            {
+              kind: "local",
+              local: "defaultFunction",
+              exported: "default",
+            },
+          ],
         });
       }),
     ]);
   });
 
-  it("ignore option", function () {
+  it("ignore option", function() {
     return Promise.all([
       transformAsync("", {
         ignore: ["/foo"],
@@ -610,7 +713,7 @@ describe("api", function () {
     ]);
   });
 
-  it("only option", function () {
+  it("only option", function() {
     return Promise.all([
       transformAsync("", {
         only: ["/foo"],
@@ -649,23 +752,23 @@ describe("api", function () {
     ]);
   });
 
-  describe("env option", function () {
+  describe("env option", function() {
     const oldBabelEnv = process.env.BABEL_ENV;
     const oldNodeEnv = process.env.NODE_ENV;
 
-    setup(function () {
+    setup(function() {
       // Tests need to run with the default and specific values for these. They
       // need to be cleared for each test.
       delete process.env.BABEL_ENV;
       delete process.env.NODE_ENV;
     });
 
-    suiteTeardown(function () {
+    suiteTeardown(function() {
       process.env.BABEL_ENV = oldBabelEnv;
       process.env.NODE_ENV = oldNodeEnv;
     });
 
-    it("default", function () {
+    it("default", function() {
       const result = babel.transform("foo;", {
         env: {
           development: { code: false },
@@ -675,7 +778,7 @@ describe("api", function () {
       assert.equal(result.code, undefined);
     });
 
-    it("BABEL_ENV", function () {
+    it("BABEL_ENV", function() {
       process.env.BABEL_ENV = "foo";
       const result = babel.transform("foo;", {
         env: {
@@ -685,7 +788,7 @@ describe("api", function () {
       assert.equal(result.code, undefined);
     });
 
-    it("NODE_ENV", function () {
+    it("NODE_ENV", function() {
       process.env.NODE_ENV = "foo";
       const result = babel.transform("foo;", {
         env: {
@@ -696,41 +799,43 @@ describe("api", function () {
     });
   });
 
-  it("resolveModuleSource option", function () {
+  it("resolveModuleSource option", function() {
     /* eslint-disable max-len */
-    const actual = "import foo from \"foo-import-default\";\nimport \"foo-import-bare\";\nexport { foo } from \"foo-export-named\";";
-    const expected = "import foo from \"resolved/foo-import-default\";\nimport \"resolved/foo-import-bare\";\nexport { foo } from \"resolved/foo-export-named\";";
+    const actual =
+      'import foo from "foo-import-default";\nimport "foo-import-bare";\nexport { foo } from "foo-export-named";';
+    const expected =
+      'import foo from "resolved/foo-import-default";\nimport "resolved/foo-import-bare";\nexport { foo } from "resolved/foo-export-named";';
     /* eslint-enable max-len */
 
     return transformAsync(actual, {
-      resolveModuleSource: function (originalSource) {
+      resolveModuleSource: function(originalSource) {
         return "resolved/" + originalSource;
       },
-    }).then(function (result) {
+    }).then(function(result) {
       assert.equal(result.code.trim(), expected);
     });
   });
 
-  describe("buildExternalHelpers", function () {
-    it("all", function () {
+  describe("buildExternalHelpers", function() {
+    it("all", function() {
       const script = buildExternalHelpers();
       assert.ok(script.indexOf("classCallCheck") >= -1);
       assert.ok(script.indexOf("inherits") >= 0);
     });
 
-    it("whitelist", function () {
+    it("whitelist", function() {
       const script = buildExternalHelpers(["inherits"]);
       assert.ok(script.indexOf("classCallCheck") === -1);
       assert.ok(script.indexOf("inherits") >= 0);
     });
 
-    it("empty whitelist", function () {
+    it("empty whitelist", function() {
       const script = buildExternalHelpers([]);
       assert.ok(script.indexOf("classCallCheck") === -1);
       assert.ok(script.indexOf("inherits") === -1);
     });
 
-    it("underscored", function () {
+    it("underscored", function() {
       const script = buildExternalHelpers(["typeof"]);
       assert.ok(script.indexOf("typeof") >= 0);
     });

packages/babel-core/test/browserify.js

@@ -5,7 +5,9 @@ import vm from "vm";
 
 describe("browserify", function() {
   it("babel/register may be used without breaking browserify", function(done) {
-    const bundler = browserify(path.join(__dirname, "fixtures/browserify/register.js"));
+    const bundler = browserify(
+      path.join(__dirname, "fixtures/browserify/register.js"),
+    );
 
     bundler.bundle(function(err, bundle) {
       if (err) return done(err);

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

@@ -27,7 +27,6 @@ describe("caching API", () => {
       return { arg, count: count++ };
     });
 
-
     assert.deepEqual(fn("one"), { arg: "one", count: 0 });
     assert.equal(fn("one"), fn("one"));
 
@@ -210,48 +209,97 @@ describe("caching API", () => {
       return { arg, val, val2, count: count++ };
     });
 
-    assert.deepEqual(fn("one"), { arg: "one", val: "default", val2: "another", count: 0 });
+    assert.deepEqual(fn("one"), {
+      arg: "one",
+      val: "default",
+      val2: "another",
+      count: 0,
+    });
     assert.equal(fn("one"), fn("one"));
 
-    assert.deepEqual(fn("two"), { arg: "two", val: "default", val2: "another", count: 1 });
+    assert.deepEqual(fn("two"), {
+      arg: "two",
+      val: "default",
+      val2: "another",
+      count: 1,
+    });
     assert.equal(fn("two"), fn("two"));
 
     other = "new";
 
-    assert.deepEqual(fn("one"), { arg: "one", val: "new", val2: "another", count: 2 });
+    assert.deepEqual(fn("one"), {
+      arg: "one",
+      val: "new",
+      val2: "another",
+      count: 2,
+    });
     assert.equal(fn("one"), fn("one"));
 
-    assert.deepEqual(fn("two"), { arg: "two", val: "new", val2: "another", count: 3 });
+    assert.deepEqual(fn("two"), {
+      arg: "two",
+      val: "new",
+      val2: "another",
+      count: 3,
+    });
     assert.equal(fn("two"), fn("two"));
 
     other = "default";
 
-    assert.deepEqual(fn("one"), { arg: "one", val: "default", val2: "another", count: 4 });
+    assert.deepEqual(fn("one"), {
+      arg: "one",
+      val: "default",
+      val2: "another",
+      count: 4,
+    });
     assert.equal(fn("one"), fn("one"));
 
-    assert.deepEqual(fn("two"), { arg: "two", val: "default", val2: "another", count: 5 });
+    assert.deepEqual(fn("two"), {
+      arg: "two",
+      val: "default",
+      val2: "another",
+      count: 5,
+    });
     assert.equal(fn("two"), fn("two"));
 
     other = "new";
 
-    assert.deepEqual(fn("one"), { arg: "one", val: "new", val2: "another", count: 6 });
+    assert.deepEqual(fn("one"), {
+      arg: "one",
+      val: "new",
+      val2: "another",
+      count: 6,
+    });
     assert.equal(fn("one"), fn("one"));
 
-    assert.deepEqual(fn("two"), { arg: "two", val: "new", val2: "another", count: 7 });
+    assert.deepEqual(fn("two"), {
+      arg: "two",
+      val: "new",
+      val2: "another",
+      count: 7,
+    });
     assert.equal(fn("two"), fn("two"));
 
     another = "second";
 
-    assert.deepEqual(fn("one"), { arg: "one", val: "new", val2: "second", count: 8 });
+    assert.deepEqual(fn("one"), {
+      arg: "one",
+      val: "new",
+      val2: "second",
+      count: 8,
+    });
     assert.equal(fn("one"), fn("one"));
 
-    assert.deepEqual(fn("two"), { arg: "two", val: "new", val2: "second", count: 9 });
+    assert.deepEqual(fn("two"), {
+      arg: "two",
+      val: "new",
+      val2: "second",
+      count: 9,
+    });
     assert.equal(fn("two"), fn("two"));
-
   });
 
   it("should throw if caching is never configured and not defaulting", () => {
-    const fn = makeStrongCache(() => { }, false /* autoPermacache */);
+    const fn = makeStrongCache(() => {}, false /* autoPermacache */);
 
     assert.throws(() => fn(), /Error: Caching was left unconfigured./);
   });
@@ -259,7 +307,7 @@ describe("caching API", () => {
   it("should auto-permacache by default", () => {
     let count = 0;
 
-    const fn = makeStrongCache((arg) => ({ arg, count: count++ }));
+    const fn = makeStrongCache(arg => ({ arg, count: count++ }));
 
     assert.deepEqual(fn("one"), { arg: "one", count: 0 });
     assert.equal(fn("one"), fn("one"));
@@ -333,7 +381,10 @@ describe("caching API", () => {
   it("should throw if you configure .forever after exiting", () => {
     const fn = makeStrongCache((arg, cache) => cache);
 
-    assert.throws(() => fn().forever(), /Cannot change caching after evaluation/);
+    assert.throws(
+      () => fn().forever(),
+      /Cannot change caching after evaluation/,
+    );
   });
 
   it("should throw if you configure .never after exiting", () => {
@@ -345,12 +396,18 @@ describe("caching API", () => {
   it("should throw if you configure .using after exiting", () => {
     const fn = makeStrongCache((arg, cache) => cache);
 
-    assert.throws(() => fn().using(() => null), /Cannot change caching after evaluation/);
+    assert.throws(
+      () => fn().using(() => null),
+      /Cannot change caching after evaluation/,
+    );
   });
 
   it("should throw if you configure .invalidate after exiting", () => {
     const fn = makeStrongCache((arg, cache) => cache);
 
-    assert.throws(() => fn().invalidate(() => null), /Cannot change caching after evaluation/);
+    assert.throws(
+      () => fn().invalidate(() => null),
+      /Cannot change caching after evaluation/,
+    );
   });
 });

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

@@ -4,7 +4,7 @@ import buildConfigChain from "../lib/config/build-config-chain";
 
 function fixture() {
   const args = [__dirname, "fixtures", "config"];
-  for (let i = 0; i < arguments.length; i ++) {
+  for (let i = 0; i < arguments.length; i++) {
     args.push(arguments[i]);
   }
   return path.join.apply(path, args);
@@ -14,11 +14,11 @@ function base() {
   return process.cwd();
 }
 
-describe("buildConfigChain", function () {
+describe("buildConfigChain", function() {
   let oldBabelEnv;
   let oldNodeEnv;
 
-  beforeEach(function () {
+  beforeEach(function() {
     oldBabelEnv = process.env.BABEL_ENV;
     oldNodeEnv = process.env.NODE_ENV;
 
@@ -26,7 +26,7 @@ describe("buildConfigChain", function () {
     delete process.env.NODE_ENV;
   });
 
-  afterEach(function () {
+  afterEach(function() {
     process.env.BABEL_ENV = oldBabelEnv;
     process.env.NODE_ENV = oldNodeEnv;
   });
@@ -52,7 +52,7 @@ describe("buildConfigChain", function () {
     });
   });
 
-  it("dir1", function () {
+  it("dir1", function() {
     const chain = buildConfigChain({
       filename: fixture("dir1", "src.js"),
     });
@@ -61,9 +61,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "extended",
-          ],
+          plugins: ["extended"],
         },
         alias: fixture("extended.babelrc.json"),
         loc: fixture("extended.babelrc.json"),
@@ -72,9 +70,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "root",
-          ],
+          plugins: ["root"],
         },
         alias: fixture(".babelrc"),
         loc: fixture(".babelrc"),
@@ -83,9 +79,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -105,7 +99,7 @@ describe("buildConfigChain", function () {
     assert.deepEqual(chain, expected);
   });
 
-  it("dir2", function () {
+  it("dir2", function() {
     const chain = buildConfigChain({
       filename: fixture("dir2", "src.js"),
     });
@@ -114,9 +108,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -125,9 +117,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "dir2",
-          ],
+          plugins: ["dir2"],
         },
         alias: fixture("dir2", ".babelrc"),
         loc: fixture("dir2", ".babelrc"),
@@ -147,7 +137,7 @@ describe("buildConfigChain", function () {
     assert.deepEqual(chain, expected);
   });
 
-  it("dir3", function () {
+  it("dir3", function() {
     const chain = buildConfigChain({
       filename: fixture("dir3", "src.js"),
     });
@@ -156,9 +146,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "extended",
-          ],
+          plugins: ["extended"],
         },
         alias: fixture("extended.babelrc.json"),
         loc: fixture("extended.babelrc.json"),
@@ -167,9 +155,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "root",
-          ],
+          plugins: ["root"],
         },
         alias: fixture(".babelrc"),
         loc: fixture(".babelrc"),
@@ -178,9 +164,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -200,7 +184,7 @@ describe("buildConfigChain", function () {
     assert.deepEqual(chain, expected);
   });
 
-  it("env - base", function () {
+  it("env - base", function() {
     const chain = buildConfigChain({
       filename: fixture("env", "src.js"),
     });
@@ -209,9 +193,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -220,9 +202,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "env-base",
-          ],
+          plugins: ["env-base"],
         },
         alias: fixture("env", ".babelrc"),
         loc: fixture("env", ".babelrc"),
@@ -242,7 +222,7 @@ describe("buildConfigChain", function () {
     assert.deepEqual(chain, expected);
   });
 
-  it("env - foo", function () {
+  it("env - foo", function() {
     process.env.NODE_ENV = "foo";
 
     const chain = buildConfigChain({
@@ -253,9 +233,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -264,9 +242,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "env-base",
-          ],
+          plugins: ["env-base"],
         },
         alias: fixture("env", ".babelrc"),
         loc: fixture("env", ".babelrc"),
@@ -275,9 +251,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "env-foo",
-          ],
+          plugins: ["env-foo"],
         },
         alias: fixture("env", ".babelrc.env.foo"),
         loc: fixture("env", ".babelrc.env.foo"),
@@ -297,7 +271,7 @@ describe("buildConfigChain", function () {
     assert.deepEqual(chain, expected);
   });
 
-  it("env - bar", function () {
+  it("env - bar", function() {
     process.env.NODE_ENV = "foo"; // overridden
     process.env.NODE_ENV = "bar";
 
@@ -309,9 +283,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -320,9 +292,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "env-base",
-          ],
+          plugins: ["env-base"],
         },
         alias: fixture("env", ".babelrc"),
         loc: fixture("env", ".babelrc"),
@@ -331,9 +301,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "env-bar",
-          ],
+          plugins: ["env-bar"],
         },
         alias: fixture("env", ".babelrc.env.bar"),
         loc: fixture("env", ".babelrc.env.bar"),
@@ -353,8 +321,7 @@ describe("buildConfigChain", function () {
     assert.deepEqual(chain, expected);
   });
 
-
-  it("env - foo", function () {
+  it("env - foo", function() {
     process.env.NODE_ENV = "foo";
 
     const chain = buildConfigChain({
@@ -394,7 +361,7 @@ describe("buildConfigChain", function () {
     assert.deepEqual(chain, expected);
   });
 
-  it("js-config", function () {
+  it("js-config", function() {
     const chain = buildConfigChain({
       filename: fixture("js-config", "src.js"),
     });
@@ -403,9 +370,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -414,10 +379,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "foo",
-            "bar",
-          ],
+          plugins: ["foo", "bar"],
         },
         alias: fixture("js-config", ".babelrc.js"),
         loc: fixture("js-config", ".babelrc.js"),
@@ -437,7 +399,7 @@ describe("buildConfigChain", function () {
     assert.deepEqual(chain, expected);
   });
 
-  it("js-config-function", function () {
+  it("js-config-function", function() {
     const chain = buildConfigChain({
       filename: fixture("js-config-function", "src.js"),
     });
@@ -446,9 +408,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -477,7 +437,7 @@ describe("buildConfigChain", function () {
     assert.deepEqual(chain, expected);
   });
 
-  it("js-config-default - should read transpiled export default", function () {
+  it("js-config-default - should read transpiled export default", function() {
     const chain = buildConfigChain({
       filename: fixture("js-config-default", "src.js"),
     });
@@ -486,9 +446,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -497,10 +455,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "foo",
-            "bar",
-          ],
+          plugins: ["foo", "bar"],
         },
         alias: fixture("js-config-default", ".babelrc.js"),
         loc: fixture("js-config-default", ".babelrc.js"),
@@ -519,7 +474,7 @@ describe("buildConfigChain", function () {
 
     assert.deepEqual(chain, expected);
   });
-  it("js-config-extended", function () {
+  it("js-config-extended", function() {
     const chain = buildConfigChain({
       filename: fixture("js-config-extended", "src.js"),
     });
@@ -528,9 +483,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -539,9 +492,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "extended",
-          ],
+          plugins: ["extended"],
         },
         alias: fixture("extended.babelrc.json"),
         loc: fixture("extended.babelrc.json"),
@@ -550,10 +501,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          plugins: [
-            "foo",
-            "bar",
-          ],
+          plugins: ["foo", "bar"],
         },
         alias: fixture("js-config-extended", ".babelrc.js"),
         loc: fixture("js-config-extended", ".babelrc.js"),
@@ -573,50 +521,49 @@ describe("buildConfigChain", function () {
     assert.deepEqual(chain, expected);
   });
 
-  it("json-pkg-config-no-babel - should not throw if" +
-    " package.json doesn't contain a `babel` field", function () {
-    const chain = buildConfigChain({
-      filename: fixture("json-pkg-config-no-babel", "src.js"),
-    });
+  it(
+    "json-pkg-config-no-babel - should not throw if" +
+      " package.json doesn't contain a `babel` field",
+    function() {
+      const chain = buildConfigChain({
+        filename: fixture("json-pkg-config-no-babel", "src.js"),
+      });
 
-    const expected = [
-      {
-        type: "options",
-        options: {
-          ignore: [
-            "root-ignore",
-          ],
+      const expected = [
+        {
+          type: "options",
+          options: {
+            ignore: ["root-ignore"],
+          },
+          alias: fixture(".babelignore"),
+          loc: fixture(".babelignore"),
+          dirname: fixture(),
         },
-        alias: fixture(".babelignore"),
-        loc: fixture(".babelignore"),
-        dirname: fixture(),
-      },
-      {
-        type: "options",
-        options: {
-          plugins: [
-            "json",
-          ],
+        {
+          type: "options",
+          options: {
+            plugins: ["json"],
+          },
+          alias: fixture("json-pkg-config-no-babel", ".babelrc"),
+          loc: fixture("json-pkg-config-no-babel", ".babelrc"),
+          dirname: fixture("json-pkg-config-no-babel"),
         },
-        alias: fixture("json-pkg-config-no-babel", ".babelrc"),
-        loc: fixture("json-pkg-config-no-babel", ".babelrc"),
-        dirname: fixture("json-pkg-config-no-babel"),
-      },
-      {
-        type: "arguments",
-        options: {
-          filename: fixture("json-pkg-config-no-babel", "src.js"),
+        {
+          type: "arguments",
+          options: {
+            filename: fixture("json-pkg-config-no-babel", "src.js"),
+          },
+          alias: "base",
+          loc: "base",
+          dirname: base(),
         },
-        alias: "base",
-        loc: "base",
-        dirname: base(),
-      },
-    ];
+      ];
 
-    assert.deepEqual(chain, expected);
-  });
+      assert.deepEqual(chain, expected);
+    },
+  );
 
-  it("should not ignore file matching negated file pattern", function () {
+  it("should not ignore file matching negated file pattern", function() {
     const chain = buildConfigChain({
       filename: fixture("ignore-negate", "src.js"),
     });
@@ -625,9 +572,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -636,10 +581,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "*",
-            "!src.js",
-          ],
+          ignore: ["*", "!src.js"],
         },
         alias: fixture("ignore-negate", ".babelrc"),
         loc: fixture("ignore-negate", ".babelrc"),
@@ -665,7 +607,7 @@ describe("buildConfigChain", function () {
     assert.equal(chain2, null);
   });
 
-  it("should not ignore file matching negated folder pattern", function () {
+  it("should not ignore file matching negated folder pattern", function() {
     const chain = buildConfigChain({
       filename: fixture("ignore-negate-folder", "folder", "src.js"),
     });
@@ -674,9 +616,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "root-ignore",
-          ],
+          ignore: ["root-ignore"],
         },
         alias: fixture(".babelignore"),
         loc: fixture(".babelignore"),
@@ -685,10 +625,7 @@ describe("buildConfigChain", function () {
       {
         type: "options",
         options: {
-          ignore: [
-            "*",
-            "!folder",
-          ],
+          ignore: ["*", "!folder"],
         },
         alias: fixture("ignore-negate-folder", ".babelrc"),
         loc: fixture("ignore-negate-folder", ".babelrc"),
@@ -714,83 +651,71 @@ describe("buildConfigChain", function () {
     assert.equal(chain2, null);
   });
 
-  it("js-json-config - should throw an error if both a .babelrc" +
-    " and a .babelrc.js are present", function () {
-    assert.throws(
-      function () {
+  it(
+    "js-json-config - should throw an error if both a .babelrc" +
+      " and a .babelrc.js are present",
+    function() {
+      assert.throws(function() {
         buildConfigChain({
           filename: fixture("js-json-config", "src.js"),
         });
-      },
-      /Multiple configuration files found\.(.|\n)*\.babelrc(.|\n)*\.babelrc\.js/
-    );
-  });
+      }, /Multiple configuration files found\.(.|\n)*\.babelrc(.|\n)*\.babelrc\.js/);
+    },
+  );
 
-  it("js-pkg-config - should throw an error if both a .babelrc.js" +
-    " and a package.json with a babel field are present", function () {
-    assert.throws(
-      function () {
+  it(
+    "js-pkg-config - should throw an error if both a .babelrc.js" +
+      " and a package.json with a babel field are present",
+    function() {
+      assert.throws(function() {
         buildConfigChain({
           filename: fixture("js-pkg-config", "src.js"),
         });
-      },
-      /Multiple configuration files found\.(.|\n)*\.babelrc\.js(.|\n)*package\.json/
-    );
-  });
+      }, /Multiple configuration files found\.(.|\n)*\.babelrc\.js(.|\n)*package\.json/);
+    },
+  );
 
-  it("json-pkg-config - should throw an error if both a .babelrc" +
-    " and a package.json with a babel field are present", function () {
-    assert.throws(
-      function () {
+  it(
+    "json-pkg-config - should throw an error if both a .babelrc" +
+      " and a package.json with a babel field are present",
+    function() {
+      assert.throws(function() {
         buildConfigChain({
           filename: fixture("json-pkg-config", "src.js"),
         });
-      },
-      /Multiple configuration files found\.(.|\n)*\.babelrc(.|\n)*package\.json/
-    );
+      }, /Multiple configuration files found\.(.|\n)*\.babelrc(.|\n)*package\.json/);
+    },
+  );
+
+  it("js-config-error", function() {
+    assert.throws(function() {
+      buildConfigChain({
+        filename: fixture("js-config-error", "src.js"),
+      });
+    }, /Error while loading config/);
   });
 
-  it("js-config-error", function () {
-    assert.throws(
-      function () {
-        buildConfigChain({
-          filename: fixture("js-config-error", "src.js"),
-        });
-      },
-      /Error while loading config/
-    );
+  it("js-config-error2", function() {
+    assert.throws(function() {
+      buildConfigChain({
+        filename: fixture("js-config-error2", "src.js"),
+      });
+    }, /Configuration should be an exported JavaScript object/);
   });
 
-  it("js-config-error2", function () {
-    assert.throws(
-      function () {
-        buildConfigChain({
-          filename: fixture("js-config-error2", "src.js"),
-        });
-      },
-      /Configuration should be an exported JavaScript object/
-    );
+  it("js-config-error3", function() {
+    assert.throws(function() {
+      buildConfigChain({
+        filename: fixture("js-config-error3", "src.js"),
+      });
+    }, /Configuration should be an exported JavaScript object/);
   });
 
-  it("js-config-error3", function () {
-    assert.throws(
-      function () {
-        buildConfigChain({
-          filename: fixture("js-config-error3", "src.js"),
-        });
-      },
-      /Configuration should be an exported JavaScript object/
-    );
-  });
-
-  it("json-config-error", function () {
-    assert.throws(
-      function () {
-        buildConfigChain({
-          filename: fixture("json-config-error", "src.js"),
-        });
-      },
-      /Error while parsing config/
-    );
+  it("json-config-error", function() {
+    assert.throws(function() {
+      buildConfigChain({
+        filename: fixture("json-config-error", "src.js"),
+      });
+    }, /Error while parsing config/);
   });
 });

packages/babel-core/test/evaluation.js

@@ -2,20 +2,23 @@ import traverse from "babel-traverse";
 import assert from "assert";
 import { parse } from "babylon";
 
-describe("evaluation", function () {
+describe("evaluation", function() {
   function addTest(code, type, value, notConfident) {
-    it(type + ": " + code, function () {
+    it(type + ": " + code, function() {
       const visitor = {};
 
-      visitor[type] = function (path) {
+      visitor[type] = function(path) {
         const evaluate = path.evaluate();
         assert.equal(evaluate.confident, !notConfident);
         assert.deepEqual(evaluate.value, value);
       };
 
-      traverse(parse(code, {
-        plugins: ["*"],
-      }), visitor);
+      traverse(
+        parse(code, {
+          plugins: ["*"],
+        }),
+        visitor,
+      );
     });
   }
 
@@ -56,14 +59,39 @@ describe("evaluation", function () {
   addTest("'abc' === 'xyz' || 1 === 1", "LogicalExpression", true);
   addTest("'abc' === 'xyz' || 1 === 10", "LogicalExpression", false);
   addTest("'abc' === 'abc' || config.flag === 1", "LogicalExpression", true);
-  addTest("obj.a === 'abc' || config.flag === 1", "LogicalExpression", undefined, true);
+  addTest(
+    "obj.a === 'abc' || config.flag === 1",
+    "LogicalExpression",
+    undefined,
+    true,
+  );
   addTest("'abc' !== 'abc' && config.flag === 1", "LogicalExpression", false);
   addTest("obj.a === 'abc' && 1 === 1", "LogicalExpression", undefined, true);
-  addTest("'abc' === 'abc' && (1 === 1 || config.flag)", "LogicalExpression", true);
-  addTest("'abc' === 'xyz' || (1 === 1 && config.flag)", "LogicalExpression", undefined, true);
-  addTest("'abc' === 'xyz' || (1 === 1 && 'four' === 'four')", "LogicalExpression", true);
-  addTest("'abc' === 'abc' && (1 === 1 && 'four' === 'four')", "LogicalExpression", true);
+  addTest(
+    "'abc' === 'abc' && (1 === 1 || config.flag)",
+    "LogicalExpression",
+    true,
+  );
+  addTest(
+    "'abc' === 'xyz' || (1 === 1 && config.flag)",
+    "LogicalExpression",
+    undefined,
+    true,
+  );
+  addTest(
+    "'abc' === 'xyz' || (1 === 1 && 'four' === 'four')",
+    "LogicalExpression",
+    true,
+  );
+  addTest(
+    "'abc' === 'abc' && (1 === 1 && 'four' === 'four')",
+    "LogicalExpression",
+    true,
+  );
   addTest("({})", "ObjectExpression", {});
   addTest("({a: '1'})", "ObjectExpression", { a: "1" });
-  addTest("({['a' + 'b']: 10 * 20, 'z': [1, 2, 3]})", "ObjectExpression", { ab: 200, z: [1, 2, 3] });
+  addTest("({['a' + 'b']: 10 * 20, 'z': [1, 2, 3]})", "ObjectExpression", {
+    ab: 200,
+    z: [1, 2, 3],
+  });
 });

packages/babel-core/test/fixtures/plugins/file-add-import/exec.js

@@ -0,0 +1,30 @@
+var res = transform("", {
+  plugins: [
+    function (b) {
+      return {
+        visitor: {
+          Program: function(path, state) {
+            var file = state.file;
+            file.addImport("import-star", "*", "lib");
+            file.addImport("import-default", "default", "foo");
+            file.addImport("import-alias", "bar", "baz");
+            file.addImport("import-default-alias", "quux");
+            file.addImport("import-empty", "");
+            file.addImport("import-none");
+          }
+        }
+      };
+    }
+  ]
+});
+
+var expected = multiline([
+  'import "import-none";',
+  'import "import-empty";',
+  'import { quux as _quux } from "import-default-alias";',
+  'import { bar as _baz } from "import-alias";',
+  'import _foo from "import-default";',
+  'import * as _lib from "import-star";',
+]);
+
+assert.equal(res.code, expected);

packages/babel-core/test/fixtures/transformation/misc/enforce-newline-modules-blacklist/expected.js

@@ -1,3 +1,2 @@
 export function foo() {}
-
 export function bar() {}

packages/babel-core/test/fixtures/transformation/misc/regression-1155/expected.js

@@ -3,11 +3,12 @@ var Foo = function (_Bar) {
 
   function Foo(options) {
     babelHelpers.classCallCheck(this, Foo);
-
     var parentOptions = {};
+
     parentOptions.init = function () {
       this;
     };
+
     return babelHelpers.possibleConstructorReturn(this, (Foo.__proto__ || Object.getPrototypeOf(Foo)).call(this, parentOptions));
   }
 

packages/babel-core/test/fixtures/transformation/misc/regression-1168/expected.js

@@ -1,5 +1,4 @@
 function test() {
   var x = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : "hi";
-
   return x;
-}
+}

packages/babel-core/test/fixtures/transformation/misc/regression-1169/expected.js

@@ -2,30 +2,10 @@ function foo() {
   var input = ['a', 'b', 'c'];
   var output = {};
 
-  var _iteratorNormalCompletion = true;
-  var _didIteratorError = false;
-  var _iteratorError = undefined;
-
-  try {
-    for (var _iterator = input[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
-      var c = _step.value;
-
-      var name = c;
-      output[name] = name;
-    }
-  } catch (err) {
-    _didIteratorError = true;
-    _iteratorError = err;
-  } finally {
-    try {
-      if (!_iteratorNormalCompletion && _iterator.return) {
-        _iterator.return();
-      }
-    } finally {
-      if (_didIteratorError) {
-        throw _iteratorError;
-      }
-    }
+  for (var _i = 0; _i < input.length; _i++) {
+    var c = input[_i];
+    var name = c;
+    output[name] = name;
   }
 
   return output;

packages/babel-core/test/fixtures/transformation/misc/regression-2765/actual.js

@@ -2,7 +2,7 @@ function f() {
   let g = async () => {
     this;
   };
-};
+}
 
 class Class {
   async m() {

packages/babel-core/test/fixtures/transformation/misc/regression-2765/expected.js

@@ -10,7 +10,7 @@ function f() {
       return _ref.apply(this, arguments);
     };
   }();
-};
+}
 
 class Class {
   m() {
@@ -28,4 +28,5 @@ class Class {
       }();
     })();
   }
+
 }

packages/babel-core/test/fixtures/transformation/misc/regression-4855/expected.js

@@ -1,7 +1,8 @@
 "use strict";
 
 var _values = values;
-value = _values[fieldName];
-rest = babelHelpers.objectWithoutProperties(_values, [fieldName]);
-
-var error = void 0;
+var _fieldName = fieldName;
+value = _values[_fieldName];
+rest = babelHelpers.objectWithoutProperties(_values, [_fieldName].map(babelHelpers.toPropertyKey));
+_values;
+var error = void 0;

packages/babel-core/test/fixtures/transformation/misc/shebang/expected.js

@@ -1,4 +1,2 @@
 #!/usr/bin/env node
-
-
 foobar();

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

@@ -6,55 +6,51 @@ describe("option-manager", () => {
   it("throws for babel 5 plugin", () => {
     return assert.throws(() => {
       manageOptions({
-        plugins: [
-          ({ Plugin }) => new Plugin("object-assign", {}),
-        ],
+        plugins: [({ Plugin }) => new Plugin("object-assign", {})],
       });
     }, /Babel 5 plugin is being run with Babel 6/);
   });
 
   describe("mergeOptions", () => {
     it("throws for removed babel 5 options", () => {
-      return assert.throws(
-        () => {
-          manageOptions({
-            "randomOption": true,
-          });
-        },
-        /Unknown option: base.randomOption/
-      );
+      return assert.throws(() => {
+        manageOptions({
+          randomOption: true,
+        });
+      }, /Unknown option: base.randomOption/);
     });
 
     it("throws for removed babel 5 options", () => {
       return assert.throws(
         () => {
           manageOptions({
-            "auxiliaryComment": true,
-            "blacklist": true,
+            auxiliaryComment: true,
+            blacklist: true,
           });
         },
         // eslint-disable-next-line max-len
-        /Using removed Babel 5 option: base.auxiliaryComment - Use `auxiliaryCommentBefore` or `auxiliaryCommentAfter`/
+        /Using removed Babel 5 option: base.auxiliaryComment - Use `auxiliaryCommentBefore` or `auxiliaryCommentAfter`/,
       );
     });
 
     it("throws for resolved but erroring preset", () => {
-      return assert.throws(
-        () => {
-          manageOptions({
-            "presets": [path.join(__dirname, "fixtures/option-manager/not-a-preset")],
-          });
-        },
-        /While processing: .*option-manager(?:\/|\\\\)not-a-preset\.js/
-      );
+      return assert.throws(() => {
+        manageOptions({
+          presets: [
+            path.join(__dirname, "fixtures/option-manager/not-a-preset"),
+          ],
+        });
+      }, /While processing: .*option-manager(?:\/|\\\\)not-a-preset\.js/);
     });
   });
 
-  describe("presets", function () {
+  describe("presets", function() {
     function presetTest(name) {
-      it(name, function () {
+      it(name, function() {
         const { options, passes } = manageOptions({
-          "presets": [path.join(__dirname, "fixtures/option-manager/presets", name)],
+          presets: [
+            path.join(__dirname, "fixtures/option-manager/presets", name),
+          ],
         });
 
         assert.equal(true, Array.isArray(options.plugins));
@@ -65,10 +61,16 @@ describe("option-manager", () => {
     }
 
     function presetThrowsTest(name, msg) {
-      it(name, function () {
-        assert.throws(() => manageOptions({
-          "presets": [path.join(__dirname, "fixtures/option-manager/presets", name)],
-        }), msg);
+      it(name, function() {
+        assert.throws(
+          () =>
+            manageOptions({
+              presets: [
+                path.join(__dirname, "fixtures/option-manager/presets", name),
+              ],
+            }),
+          msg,
+        );
       });
     }
 
@@ -77,7 +79,10 @@ describe("option-manager", () => {
     presetTest("es2015_default_function");
     presetTest("es2015_default_object");
 
-    presetThrowsTest("es2015_named", /Must export a default export when using ES6 modules/);
+    presetThrowsTest(
+      "es2015_named",
+      /Must export a default export when using ES6 modules/,
+    );
     presetThrowsTest("es2015_invalid", /Unsupported format: string/);
     presetThrowsTest("es5_invalid", /Unsupported format: string/);
   });

packages/babel-core/test/path.js

@@ -2,152 +2,172 @@ import { transform } from "../lib/index";
 import Plugin from "../lib/config/plugin";
 import chai from "chai";
 
-describe("traversal path", function () {
-  it("replaceWithSourceString", function () {
+describe("traversal path", function() {
+  it("replaceWithSourceString", function() {
     const expectCode = "function foo() {}";
 
     const actualCode = transform(expectCode, {
-      plugins: [new Plugin({
-        visitor: {
-          FunctionDeclaration: function (path) {
-            path.replaceWithSourceString("console.whatever()");
+      plugins: [
+        new Plugin({
+          visitor: {
+            FunctionDeclaration: function(path) {
+              path.replaceWithSourceString("console.whatever()");
+            },
           },
-        },
-      })],
+        }),
+      ],
     }).code;
 
     chai.expect(actualCode).to.be.equal("console.whatever();");
   });
 
-  it("replaceWith (arrow expression body to block statement body)", function () {
+  it("replaceWith (arrow expression body to block statement body)", function() {
     const expectCode = "var fn = () => true;";
 
     const actualCode = transform(expectCode, {
-      plugins: [new Plugin({
-        visitor: {
-          ArrowFunctionExpression: function (path) {
-            path.get("body").replaceWith({
-              type: "BlockStatement",
-              body: [{
-                type: "ReturnStatement",
-                argument: {
-                  type: "BooleanLiteral",
-                  value: true,
-                },
-              }],
-            });
+      plugins: [
+        new Plugin({
+          visitor: {
+            ArrowFunctionExpression: function(path) {
+              path.get("body").replaceWith({
+                type: "BlockStatement",
+                body: [
+                  {
+                    type: "ReturnStatement",
+                    argument: {
+                      type: "BooleanLiteral",
+                      value: true,
+                    },
+                  },
+                ],
+              });
+            },
           },
-        },
-      })],
+        }),
+      ],
     }).code;
 
     chai.expect(actualCode).to.be.equal("var fn = () => {\n  return true;\n};");
   });
 
-  it("replaceWith (arrow block statement body to expression body)", function () {
+  it("replaceWith (arrow block statement body to expression body)", function() {
     const expectCode = "var fn = () => { return true; }";
 
     const actualCode = transform(expectCode, {
-      plugins: [new Plugin({
-        visitor: {
-          ArrowFunctionExpression: function (path) {
-            path.get("body").replaceWith({
-              type: "BooleanLiteral",
-              value: true,
-            });
+      plugins: [
+        new Plugin({
+          visitor: {
+            ArrowFunctionExpression: function(path) {
+              path.get("body").replaceWith({
+                type: "BooleanLiteral",
+                value: true,
+              });
+            },
           },
-        },
-      })],
+        }),
+      ],
     }).code;
 
     chai.expect(actualCode).to.be.equal("var fn = () => true;");
   });
 
-  it("replaceWith (for-in left expression to variable declaration)", function () {
+  it("replaceWith (for-in left expression to variable declaration)", function() {
     const expectCode = "for (KEY in right);";
 
     const actualCode = transform(expectCode, {
-      plugins: [new Plugin({
-        visitor: {
-          ForInStatement: function (path) {
-            path.get("left").replaceWith({
-              type: "VariableDeclaration",
-              kind: "var",
-              declarations: [{
-                type: "VariableDeclarator",
-                id: {
-                  type: "Identifier",
-                  name: "KEY",
-                },
-              }],
-            });
+      plugins: [
+        new Plugin({
+          visitor: {
+            ForInStatement: function(path) {
+              path.get("left").replaceWith({
+                type: "VariableDeclaration",
+                kind: "var",
+                declarations: [
+                  {
+                    type: "VariableDeclarator",
+                    id: {
+                      type: "Identifier",
+                      name: "KEY",
+                    },
+                  },
+                ],
+              });
+            },
           },
-        },
-      })],
+        }),
+      ],
     }).code;
 
     chai.expect(actualCode).to.be.equal("for (var KEY in right);");
   });
 
-  it("replaceWith (for-in left variable declaration to expression)", function () {
+  it("replaceWith (for-in left variable declaration to expression)", function() {
     const expectCode = "for (var KEY in right);";
 
     const actualCode = transform(expectCode, {
-      plugins: [new Plugin({
-        visitor: {
-          ForInStatement: function (path) {
-            path.get("left").replaceWith({
-              type: "Identifier",
-              name: "KEY",
-            });
+      plugins: [
+        new Plugin({
+          visitor: {
+            ForInStatement: function(path) {
+              path.get("left").replaceWith({
+                type: "Identifier",
+                name: "KEY",
+              });
+            },
           },
-        },
-      })],
+        }),
+      ],
     }).code;
 
     chai.expect(actualCode).to.be.equal("for (KEY in right);");
   });
 
-  it("replaceWith (for-loop left expression to variable declaration)", function () {
+  it("replaceWith (for-loop left expression to variable declaration)", function() {
     const expectCode = "for (KEY;;);";
 
     const actualCode = transform(expectCode, {
-      plugins: [new Plugin({
-        visitor: {
-          ForStatement: function (path) {
-            path.get("init").replaceWith({
-              type: "VariableDeclaration",
-              kind: "var",
-              declarations: [{
-                type: "VariableDeclarator",
-                id: {
-                  type: "Identifier",
-                  name: "KEY",
-                },
-              }],
-            });
+      plugins: [
+        new Plugin({
+          visitor: {
+            ForStatement: function(path) {
+              path.get("init").replaceWith({
+                type: "VariableDeclaration",
+                kind: "var",
+                declarations: [
+                  {
+                    type: "VariableDeclarator",
+                    id: {
+                      type: "Identifier",
+                      name: "KEY",
+                    },
+                  },
+                ],
+              });
+            },
           },
-        },
-      })],
+        }),
+      ],
     }).code;
 
     chai.expect(actualCode).to.be.equal("for (var KEY;;);");
   });
 
-  it("replaceWith (for-loop left variable declaration to expression)", function () {
+  it("replaceWith (for-loop left variable declaration to expression)", function() {
     const expectCode = "for (var KEY;;);";
 
     const actualCode = transform(expectCode, {
-      plugins: [new Plugin({
-        visitor: {
-          ForStatement: function (path) {
-            path.get("init").replaceWith({
-              type: "Identifier",
-              name: "KEY",
-            });
+      plugins: [
+        new Plugin({
+          visitor: {
+            ForStatement: function(path) {
+              path.get("init").replaceWith({
+                type: "Identifier",
+                name: "KEY",
+              });
+            },
           },
-        },
-      })],
+        }),
+      ],
     }).code;
 
     chai.expect(actualCode).to.be.equal("for (KEY;;);");

packages/babel-core/test/resolution.js

@@ -2,7 +2,7 @@ import assert from "assert";
 import * as babel from "../lib/index";
 import path from "path";
 
-describe("addon resolution", function () {
+describe("addon resolution", function() {
   const base = path.join(__dirname, "fixtures", "resolution");
 
   beforeEach(function() {
@@ -20,9 +20,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "module:preset",
-      ],
+      presets: ["module:preset"],
     });
   });
 
@@ -32,9 +30,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "module:plugin",
-      ],
+      plugins: ["module:plugin"],
     });
   });
 
@@ -44,9 +40,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "mod",
-      ],
+      presets: ["mod"],
     });
   });
 
@@ -56,9 +50,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "mod",
-      ],
+      plugins: ["mod"],
     });
   });
 
@@ -68,9 +60,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "babel-preset-mod",
-      ],
+      presets: ["babel-preset-mod"],
     });
   });
 
@@ -80,9 +70,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "babel-plugin-mod",
-      ],
+      plugins: ["babel-plugin-mod"],
     });
   });
 
@@ -92,9 +80,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "@babel/foo",
-      ],
+      presets: ["@babel/foo"],
     });
   });
 
@@ -104,9 +90,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "@babel/foo",
-      ],
+      plugins: ["@babel/foo"],
     });
   });
 
@@ -116,9 +100,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "@babel/preset-foo",
-      ],
+      presets: ["@babel/preset-foo"],
     });
   });
 
@@ -128,9 +110,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "@babel/plugin-foo",
-      ],
+      plugins: ["@babel/plugin-foo"],
     });
   });
 
@@ -140,9 +120,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "@foo/mod",
-      ],
+      presets: ["@foo/mod"],
     });
   });
 
@@ -152,9 +130,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "@foo/mod",
-      ],
+      plugins: ["@foo/mod"],
     });
   });
 
@@ -164,9 +140,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "@foo/babel-preset-mod",
-      ],
+      presets: ["@foo/babel-preset-mod"],
     });
   });
 
@@ -176,9 +150,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "@foo/babel-plugin-mod",
-      ],
+      plugins: ["@foo/babel-plugin-mod"],
     });
   });
 
@@ -188,9 +160,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "./dir/preset.js",
-      ],
+      presets: ["./dir/preset.js"],
     });
   });
 
@@ -200,9 +170,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "./dir/plugin.js",
-      ],
+      plugins: ["./dir/plugin.js"],
     });
   });
 
@@ -212,9 +180,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "mod/preset",
-      ],
+      presets: ["mod/preset"],
     });
   });
 
@@ -224,9 +190,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "mod/plugin",
-      ],
+      plugins: ["mod/plugin"],
     });
   });
 
@@ -236,9 +200,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "@foo/mod/preset",
-      ],
+      presets: ["@foo/mod/preset"],
     });
   });
 
@@ -248,9 +210,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "@foo/mod/plugin",
-      ],
+      plugins: ["@foo/mod/plugin"],
     });
   });
 
@@ -260,9 +220,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      presets: [
-        "@babel/mod/preset",
-      ],
+      presets: ["@babel/mod/preset"],
     });
   });
 
@@ -272,9 +230,7 @@ describe("addon resolution", function () {
     babel.transform("", {
       filename: "filename.js",
       babelrc: false,
-      plugins: [
-        "@babel/mod/plugin",
-      ],
+      plugins: ["@babel/mod/plugin"],
     });
   });
 
@@ -285,9 +241,7 @@ describe("addon resolution", function () {
       babel.transform("", {
         filename: "filename.js",
         babelrc: false,
-        presets: [
-          "foo",
-        ],
+        presets: ["foo"],
       });
       // eslint-disable-next-line max-len
     }, /Cannot find module 'babel-preset-foo'.*\n- If you want to resolve "foo", use "module:foo"/);
@@ -300,9 +254,7 @@ describe("addon resolution", function () {
       babel.transform("", {
         filename: "filename.js",
         babelrc: false,
-        plugins: [
-          "foo",
-        ],
+        plugins: ["foo"],
       });
       // eslint-disable-next-line max-len
     }, /Cannot find module 'babel-plugin-foo'.*\n- If you want to resolve "foo", use "module:foo"/);
@@ -315,9 +267,7 @@ describe("addon resolution", function () {
       babel.transform("", {
         filename: "filename.js",
         babelrc: false,
-        presets: [
-          "foo",
-        ],
+        presets: ["foo"],
       });
       // eslint-disable-next-line max-len
     }, /Cannot find module 'babel-preset-foo'.*\n- Did you mean "@babel\/foo"\?/);
@@ -330,9 +280,7 @@ describe("addon resolution", function () {
       babel.transform("", {
         filename: "filename.js",
         babelrc: false,
-        plugins: [
-          "foo",
-        ],
+        plugins: ["foo"],
       });
       // eslint-disable-next-line max-len
     }, /Cannot find module 'babel-plugin-foo'.*\n- Did you mean "@babel\/foo"\?/);
@@ -345,9 +293,7 @@ describe("addon resolution", function () {
       babel.transform("", {
         filename: "filename.js",
         babelrc: false,
-        presets: [
-          "testplugin",
-        ],
+        presets: ["testplugin"],
       });
       // eslint-disable-next-line max-len
     }, /Cannot find module 'babel-preset-testplugin'.*\n- Did you accidentally pass a preset as a plugin\?/);
@@ -360,9 +306,7 @@ describe("addon resolution", function () {
       babel.transform("", {
         filename: "filename.js",
         babelrc: false,
-        plugins: [
-          "testpreset",
-        ],
+        plugins: ["testpreset"],
       });
       // eslint-disable-next-line max-len
     }, /Cannot find module 'babel-plugin-testpreset'.*\n- Did you accidentally pass a plugin as a preset\?/);
@@ -375,9 +319,7 @@ describe("addon resolution", function () {
       babel.transform("", {
         filename: "filename.js",
         babelrc: false,
-        presets: [
-          "foo",
-        ],
+        presets: ["foo"],
       });
     }, /Cannot find module 'babel-preset-foo'/);
   });
@@ -389,9 +331,7 @@ describe("addon resolution", function () {
       babel.transform("", {
         filename: "filename.js",
         babelrc: false,
-        plugins: [
-          "foo",
-        ],
+        plugins: ["foo"],
       });
     }, /Cannot find module 'babel-plugin-foo'/);
   });

packages/babel-generator/package.json

@@ -1,6 +1,6 @@
 {
   "name": "babel-generator",
-  "version": "7.0.0-alpha.12",
+  "version": "7.0.0-alpha.19",
   "description": "Turns an AST into code.",
   "author": "Sebastian McKenzie <sebmck@gmail.com>",
   "homepage": "https://babeljs.io/",
@@ -11,16 +11,15 @@
     "lib"
   ],
   "dependencies": {
-    "babel-messages": "7.0.0-alpha.12",
-    "babel-types": "7.0.0-alpha.12",
-    "detect-indent": "^4.0.0",
-    "jsesc": "^1.3.0",
+    "babel-messages": "7.0.0-alpha.19",
+    "babel-types": "7.0.0-alpha.19",
+    "jsesc": "^2.5.1",
     "lodash": "^4.2.0",
     "source-map": "^0.5.0",
     "trim-right": "^1.0.1"
   },
   "devDependencies": {
-    "babel-helper-fixtures": "7.0.0-alpha.12",
-    "babylon": "^7.0.0-beta.12"
+    "babel-helper-fixtures": "7.0.0-alpha.19",
+    "babylon": "^7.0.0-beta.19"
   }
 }

packages/babel-generator/src/buffer.js

@@ -54,7 +54,7 @@ export default class Buffer {
         configurable: true,
         enumerable: true,
         get() {
-          return this.map = map.get();
+          return (this.map = map.get());
         },
         set(value) {
           Object.defineProperty(this, "map", { value, writable: true });
@@ -81,7 +81,11 @@ export default class Buffer {
 
   queue(str: string): void {
     // Drop trailing spaces when a newline is inserted.
-    if (str === "\n") while (this._queue.length > 0 && SPACES_RE.test(this._queue[0][0])) this._queue.shift();
+    if (str === "\n") {
+      while (this._queue.length > 0 && SPACES_RE.test(this._queue[0][0])) {
+        this._queue.shift();
+      }
+    }
 
     const { line, column, filename, identifierName } = this._sourcePosition;
     this._queue.unshift([str, line, column, identifierName, filename]);
@@ -89,13 +93,26 @@ export default class Buffer {
 
   _flush(): void {
     let item;
-    while (item = this._queue.pop()) this._append(...item);
+    while ((item = this._queue.pop())) this._append(...item);
   }
 
-  _append(str: string, line: number, column: number, identifierName: ?string, filename: ?string): void {
+  _append(
+    str: string,
+    line: number,
+    column: number,
+    identifierName: ?string,
+    filename: ?string,
+  ): void {
     // If there the line is ending, adding a new mapping marker is redundant
     if (this._map && str[0] !== "\n") {
-      this._map.mark(this._position.line, this._position.column, line, column, identifierName, filename);
+      this._map.mark(
+        this._position.line,
+        this._position.column,
+        line,
+        column,
+        identifierName,
+        filename,
+      );
     }
 
     this._buf.push(str);
@@ -112,11 +129,15 @@ export default class Buffer {
   }
 
   removeTrailingNewline(): void {
-    if (this._queue.length > 0 && this._queue[0][0] === "\n") this._queue.shift();
+    if (this._queue.length > 0 && this._queue[0][0] === "\n") {
+      this._queue.shift();
+    }
   }
 
   removeLastSemicolon(): void {
-    if (this._queue.length > 0 && this._queue[0][0] === ";") this._queue.shift();
+    if (this._queue.length > 0 && this._queue[0][0] === ";") {
+      this._queue.shift();
+    }
   }
 
   endsWith(suffix: string): boolean {
@@ -133,7 +154,8 @@ export default class Buffer {
       return last === suffix;
     }
 
-    const end = this._last + this._queue.reduce((acc, item) => item[0] + acc, "");
+    const end =
+      this._last + this._queue.reduce((acc, item) => item[0] + acc, "");
     if (suffix.length <= end.length) {
       return end.slice(-suffix.length) === suffix;
     }
@@ -157,10 +179,10 @@ export default class Buffer {
 
     const pos = loc ? loc[prop] : null;
 
-    this._sourcePosition.identifierName = loc && loc.identifierName || null;
+    this._sourcePosition.identifierName = (loc && loc.identifierName) || null;
     this._sourcePosition.line = pos ? pos.line : null;
     this._sourcePosition.column = pos ? pos.column : null;
-    this._sourcePosition.filename = loc && loc.filename || null;
+    this._sourcePosition.filename = (loc && loc.filename) || null;
   }
 
   /**
@@ -190,7 +212,9 @@ export default class Buffer {
     const extra = this._queue.reduce((acc, item) => item[0] + acc, "");
     const lastIndex = extra.lastIndexOf("\n");
 
-    return lastIndex === -1 ? this._position.column + extra.length : (extra.length - 1 - lastIndex);
+    return lastIndex === -1
+      ? this._position.column + extra.length
+      : extra.length - 1 - lastIndex;
   }
 
   getCurrentLine(): number {

packages/babel-generator/src/generators/classes.js

@@ -8,6 +8,18 @@ export function ClassDeclaration(node: Object, parent: Object) {
     this.printJoin(node.decorators, node);
   }
 
+  if (node.declare) {
+    // TS
+    this.word("declare");
+    this.space();
+  }
+
+  if (node.abstract) {
+    // TS
+    this.word("abstract");
+    this.space();
+  }
+
   this.word("class");
 
   if (node.id) {
@@ -59,10 +71,25 @@ export function ClassBody(node: Object) {
 export function ClassProperty(node: Object) {
   this.printJoin(node.decorators, node);
 
+  if (node.accessibility) {
+    // TS
+    this.word(node.accessibility);
+    this.space();
+  }
   if (node.static) {
     this.word("static");
     this.space();
   }
+  if (node.abstract) {
+    // TS
+    this.word("abstract");
+    this.space();
+  }
+  if (node.readonly) {
+    // TS
+    this.word("readonly");
+    this.space();
+  }
   if (node.computed) {
     this.token("[");
     this.print(node.key, node);
@@ -71,6 +98,12 @@ export function ClassProperty(node: Object) {
     this._variance(node);
     this.print(node.key, node);
   }
+
+  if (node.optional) {
+    // TS
+    this.token("?");
+  }
+
   this.print(node.typeAnnotation, node);
   if (node.value) {
     this.space();
@@ -82,12 +115,30 @@ export function ClassProperty(node: Object) {
 }
 
 export function ClassMethod(node: Object) {
+  this._classMethodHead(node);
+  this.space();
+  this.print(node.body, node);
+}
+
+export function _classMethodHead(node) {
   this.printJoin(node.decorators, node);
 
+  if (node.accessibility) {
+    // TS
+    this.word(node.accessibility);
+    this.space();
+  }
+
+  if (node.abstract) {
+    // TS
+    this.word("abstract");
+    this.space();
+  }
+
   if (node.static) {
     this.word("static");
     this.space();
   }
 
-  this._method(node);
+  this._methodHead(node);
 }

packages/babel-generator/src/generators/expressions.js

@@ -1,9 +1,12 @@
 import * as t from "babel-types";
 import * as n from "../node";
 
-
 export function UnaryExpression(node: Object) {
-  if (node.operator === "void" || node.operator === "delete" || node.operator === "typeof") {
+  if (
+    node.operator === "void" ||
+    node.operator === "delete" ||
+    node.operator === "typeof"
+  ) {
     this.word(node.operator);
     this.space();
   } else {
@@ -51,11 +54,22 @@ export function NewExpression(node: Object, parent: Object) {
   this.word("new");
   this.space();
   this.print(node.callee, node);
-  if (node.arguments.length === 0 && this.format.minified &&
-      !t.isCallExpression(parent, { callee: node }) &&
-      !t.isMemberExpression(parent) &&
-      !t.isNewExpression(parent)) return;
+  if (
+    this.format.minified &&
+    node.arguments.length === 0 &&
+    !node.optional &&
+    !t.isCallExpression(parent, { callee: node }) &&
+    !t.isMemberExpression(parent) &&
+    !t.isNewExpression(parent)
+  ) {
+    return;
+  }
 
+  this.print(node.typeParameters, node); // TS
+
+  if (node.optional) {
+    this.token("?.");
+  }
   this.token("(");
   this.printList(node.arguments, node);
   this.token(")");
@@ -79,34 +93,16 @@ export function Decorator(node: Object) {
   this.newline();
 }
 
-function commaSeparatorNewline() {
-  this.token(",");
-  this.newline();
-
-  if (!this.endsWith("\n")) this.space();
-}
-
 export function CallExpression(node: Object) {
   this.print(node.callee, node);
 
+  this.print(node.typeParameters, node); // TS
+
+  if (node.optional) {
+    this.token("?.");
+  }
   this.token("(");
-
-  const isPrettyCall = node._prettyCall;
-
-  let separator;
-  if (isPrettyCall) {
-    separator = commaSeparatorNewline;
-    this.newline();
-    this.indent();
-  }
-
-  this.printList(node.arguments, node, { separator });
-
-  if (isPrettyCall) {
-    this.newline();
-    this.dedent();
-  }
-
+  this.printList(node.arguments, node);
   this.token(")");
 }
 
@@ -115,7 +111,7 @@ export function Import() {
 }
 
 function buildYieldAwait(keyword: string) {
-  return function (node: Object) {
+  return function(node: Object) {
     this.word(keyword);
 
     if (node.delegate) {
@@ -156,8 +152,10 @@ export function AssignmentPattern(node: Object) {
 export function AssignmentExpression(node: Object, parent: Object) {
   // Somewhere inside a for statement `init` node but doesn't usually
   // needs a paren except for `in` expressions: `for (a in b ? a : b;;)`
-  const parens = this.inForStatementInitCounter && node.operator === "in" &&
-               !n.needsParens(node, parent);
+  const parens =
+    this.inForStatementInitCounter &&
+    node.operator === "in" &&
+    !n.needsParens(node, parent);
 
   if (parens) {
     this.token("(");
@@ -203,12 +201,17 @@ export function MemberExpression(node: Object) {
     computed = true;
   }
 
+  if (node.optional) {
+    this.token("?.");
+  }
   if (computed) {
     this.token("[");
     this.print(node.property, node);
     this.token("]");
   } else {
-    this.token(".");
+    if (!node.optional) {
+      this.token(".");
+    }
     this.print(node.property, node);
   }
 }

packages/babel-generator/src/generators/flow.js

@@ -1,3 +1,6 @@
+import * as t from "babel-types";
+import { ExportAllDeclaration } from "./modules";
+
 export function AnyTypeAnnotation() {
   this.word("any");
 }
@@ -20,24 +23,47 @@ export function NullLiteralTypeAnnotation() {
   this.word("null");
 }
 
-export function DeclareClass(node: Object) {
-  this.word("declare");
-  this.space();
+export function DeclareClass(node: Object, parent: Object) {
+  if (!t.isDeclareExportDeclaration(parent)) {
+    this.word("declare");
+    this.space();
+  }
   this.word("class");
   this.space();
   this._interfaceish(node);
 }
 
-export function DeclareFunction(node: Object) {
-  this.word("declare");
-  this.space();
+export function DeclareFunction(node: Object, parent: Object) {
+  if (!t.isDeclareExportDeclaration(parent)) {
+    this.word("declare");
+    this.space();
+  }
   this.word("function");
   this.space();
   this.print(node.id, node);
   this.print(node.id.typeAnnotation.typeAnnotation, node);
+
+  if (node.predicate) {
+    this.space();
+    this.print(node.predicate, node);
+  }
+
   this.semicolon();
 }
 
+export function InferredPredicate(/*node: Object*/) {
+  this.token("%");
+  this.word("checks");
+}
+
+export function DeclaredPredicate(node: Object) {
+  this.token("%");
+  this.word("checks");
+  this.token("(");
+  this.print(node.value, node);
+  this.token(")");
+}
+
 export function DeclareInterface(node: Object) {
   this.word("declare");
   this.space();
@@ -69,9 +95,19 @@ export function DeclareTypeAlias(node: Object) {
   this.TypeAlias(node);
 }
 
-export function DeclareVariable(node: Object) {
-  this.word("declare");
-  this.space();
+export function DeclareOpaqueType(node: Object, parent: Object) {
+  if (!t.isDeclareExportDeclaration(parent)) {
+    this.word("declare");
+    this.space();
+  }
+  this.OpaqueType(node);
+}
+
+export function DeclareVariable(node: Object, parent: Object) {
+  if (!t.isDeclareExportDeclaration(parent)) {
+    this.word("declare");
+    this.space();
+  }
   this.word("var");
   this.space();
   this.print(node.id, node);
@@ -79,6 +115,50 @@ export function DeclareVariable(node: Object) {
   this.semicolon();
 }
 
+export function DeclareExportDeclaration(node: Object) {
+  this.word("declare");
+  this.space();
+  this.word("export");
+  this.space();
+  if (node.default) {
+    this.word("default");
+    this.space();
+  }
+
+  FlowExportDeclaration.apply(this, arguments);
+}
+
+export function DeclareExportAllDeclaration(/*node: Object*/) {
+  this.word("declare");
+  this.space();
+  ExportAllDeclaration.apply(this, arguments);
+}
+
+function FlowExportDeclaration(node: Object) {
+  if (node.declaration) {
+    const declar = node.declaration;
+    this.print(declar, node);
+    if (!t.isStatement(declar)) this.semicolon();
+  } else {
+    this.token("{");
+    if (node.specifiers.length) {
+      this.space();
+      this.printList(node.specifiers, node);
+      this.space();
+    }
+    this.token("}");
+
+    if (node.source) {
+      this.space();
+      this.word("from");
+      this.space();
+      this.print(node.source, node);
+    }
+
+    this.semicolon();
+  }
+}
+
 export function ExistsTypeAnnotation() {
   this.token("*");
 }
@@ -100,7 +180,10 @@ export function FunctionTypeAnnotation(node: Object, parent: Object) {
   this.token(")");
 
   // this node type is overloaded, not sure why but it makes it EXTREMELY annoying
-  if (parent.type === "ObjectTypeCallProperty" || parent.type === "DeclareFunction") {
+  if (
+    parent.type === "ObjectTypeCallProperty" ||
+    parent.type === "DeclareFunction"
+  ) {
     this.token(":");
   } else {
     this.space();
@@ -124,7 +207,10 @@ export function InterfaceExtends(node: Object) {
   this.print(node.typeParameters, node);
 }
 
-export { InterfaceExtends as ClassImplements, InterfaceExtends as GenericTypeAnnotation };
+export {
+  InterfaceExtends as ClassImplements,
+  InterfaceExtends as GenericTypeAnnotation,
+};
 
 export function _interfaceish(node: Object) {
   this.print(node.id, node);
@@ -225,38 +311,27 @@ export function TypeAlias(node: Object) {
   this.semicolon();
 }
 
-export function TypeAnnotation(node: Object) {
-  this.token(":");
+export function OpaqueType(node: Object) {
+  this.word("opaque");
   this.space();
-  if (node.optional) this.token("?");
-  this.print(node.typeAnnotation, node);
-}
-
-export function TypeParameter(node: Object) {
-  this._variance(node);
-
-  this.word(node.name);
-
-  if (node.bound) {
-    this.print(node.bound, node);
+  this.word("type");
+  this.space();
+  this.print(node.id, node);
+  this.print(node.typeParameters, node);
+  if (node.supertype) {
+    this.token(":");
+    this.space();
+    this.print(node.supertype, node);
   }
-
-  if (node.default) {
+  if (node.impltype) {
     this.space();
     this.token("=");
     this.space();
-    this.print(node.default, node);
+    this.print(node.impltype, node);
   }
+  this.semicolon();
 }
 
-export function TypeParameterInstantiation(node: Object) {
-  this.token("<");
-  this.printList(node.params, node, {});
-  this.token(">");
-}
-
-export { TypeParameterInstantiation as TypeParameterDeclaration };
-
 export function ObjectTypeAnnotation(node: Object) {
   if (node.exact) {
     this.token("{|");
@@ -264,7 +339,11 @@ export function ObjectTypeAnnotation(node: Object) {
     this.token("{");
   }
 
-  const props = node.properties.concat(node.callProperties, node.indexers);
+  // TODO: remove the array fallbacks and instead enforce the types to require an array
+  const props = node.properties.concat(
+    node.callProperties || [],
+    node.indexers || [],
+  );
 
   if (props.length) {
     this.space();

packages/babel-generator/src/generators/index.js

@@ -8,3 +8,5 @@ export * from "./types";
 export * from "./flow";
 export * from "./base";
 export * from "./jsx";
+export * from "./tsFlowCommon";
+export * from "./typescript";

packages/babel-generator/src/generators/methods.js

@@ -3,20 +3,31 @@ import * as t from "babel-types";
 export function _params(node: Object) {
   this.print(node.typeParameters, node);
   this.token("(");
-  this.printList(node.params, node, {
-    iterator: (node) => {
-      if (node.optional) this.token("?");
-      this.print(node.typeAnnotation, node);
-    },
-  });
+  this._parameters(node.params, node);
   this.token(")");
 
-  if (node.returnType) {
-    this.print(node.returnType, node);
+  this.print(node.returnType, node);
+}
+
+export function _parameters(parameters, parent) {
+  for (let i = 0; i < parameters.length; i++) {
+    this._param(parameters[i], parent);
+
+    if (i < parameters.length - 1) {
+      this.token(",");
+      this.space();
+    }
   }
 }
 
-export function _method(node: Object) {
+export function _param(parameter, parent) {
+  this.printJoin(parameter.decorators, parameter);
+  this.print(parameter, parent);
+  if (parameter.optional) this.token("?"); // TS / flow
+  this.print(parameter.typeAnnotation, parameter); // TS / flow
+}
+
+export function _methodHead(node: Object) {
   const kind = node.kind;
   const key = node.key;
 
@@ -44,12 +55,25 @@ export function _method(node: Object) {
     this.print(key, node);
   }
 
+  if (node.optional) {
+    // TS
+    this.token("?");
+  }
+
   this._params(node);
-  this.space();
-  this.print(node.body, node);
 }
 
-export function FunctionExpression(node: Object) {
+export function _predicate(node: Object) {
+  if (node.predicate) {
+    if (!node.returnType) {
+      this.token(":");
+    }
+    this.space();
+    this.print(node.predicate, node);
+  }
+}
+
+export function _functionHead(node: Object) {
   if (node.async) {
     this.word("async");
     this.space();
@@ -57,14 +81,17 @@ export function FunctionExpression(node: Object) {
   this.word("function");
   if (node.generator) this.token("*");
 
+  this.space();
   if (node.id) {
-    this.space();
     this.print(node.id, node);
-  } else {
-    this.space();
   }
 
   this._params(node);
+  this._predicate(node);
+}
+
+export function FunctionExpression(node: Object) {
+  this._functionHead(node);
   this.space();
   this.print(node.body, node);
 }
@@ -79,12 +106,18 @@ export function ArrowFunctionExpression(node: Object) {
 
   const firstParam = node.params[0];
 
-  if (node.params.length === 1 && t.isIdentifier(firstParam) && !hasTypes(node, firstParam)) {
+  if (
+    node.params.length === 1 &&
+    t.isIdentifier(firstParam) &&
+    !hasTypes(node, firstParam)
+  ) {
     this.print(firstParam, node);
   } else {
     this._params(node);
   }
 
+  this._predicate(node);
+
   this.space();
   this.token("=>");
   this.space();
@@ -93,6 +126,11 @@ export function ArrowFunctionExpression(node: Object) {
 }
 
 function hasTypes(node, param) {
-  return node.typeParameters || node.returnType || param.typeAnnotation || param.optional ||
-    param.trailingComments;
+  return (
+    node.typeParameters ||
+    node.returnType ||
+    param.typeAnnotation ||
+    param.optional ||
+    param.trailingComments
+  );
 }

packages/babel-generator/src/generators/modules.js

@@ -44,6 +44,10 @@ export function ExportNamespaceSpecifier(node: Object) {
 export function ExportAllDeclaration(node: Object) {
   this.word("export");
   this.space();
+  if (node.exportKind === "type") {
+    this.word("type");
+    this.space();
+  }
   this.token("*");
   this.space();
   this.word("from");
@@ -91,7 +95,10 @@ function ExportDeclaration(node: Object) {
     let hasSpecial = false;
     while (true) {
       const first = specifiers[0];
-      if (t.isExportDefaultSpecifier(first) || t.isExportNamespaceSpecifier(first)) {
+      if (
+        t.isExportDefaultSpecifier(first) ||
+        t.isExportNamespaceSpecifier(first)
+      ) {
         hasSpecial = true;
         this.print(specifiers.shift(), node);
         if (specifiers.length) {
@@ -138,7 +145,10 @@ export function ImportDeclaration(node: Object) {
     // print "special" specifiers first
     while (true) {
       const first = specifiers[0];
-      if (t.isImportDefaultSpecifier(first) || t.isImportNamespaceSpecifier(first)) {
+      if (
+        t.isImportDefaultSpecifier(first) ||
+        t.isImportNamespaceSpecifier(first)
+      ) {
         this.print(specifiers.shift(), node);
         if (specifiers.length) {
           this.token(",");

packages/babel-generator/src/generators/statements.js

@@ -17,7 +17,8 @@ export function IfStatement(node: Object) {
   this.token(")");
   this.space();
 
-  const needsBlock = node.alternate && t.isIfStatement(getLastStatement(node.consequent));
+  const needsBlock =
+    node.alternate && t.isIfStatement(getLastStatement(node.consequent));
   if (needsBlock) {
     this.token("{");
     this.newline();
@@ -80,8 +81,8 @@ export function WhileStatement(node: Object) {
   this.printBlock(node);
 }
 
-const buildForXStatement = function (op) {
-  return function (node: Object) {
+const buildForXStatement = function(op) {
+  return function(node: Object) {
     this.word("for");
     this.space();
     if (op === "of" && node.await) {
@@ -116,14 +117,14 @@ export function DoWhileStatement(node: Object) {
 }
 
 function buildLabelStatement(prefix, key = "label") {
-  return function (node: Object) {
+  return function(node: Object) {
     this.word(prefix);
 
     const label = node[key];
     if (label) {
       this.space();
-
-      const terminatorState = this.startTerminatorless();
+      const isLabel = key == "label";
+      const terminatorState = this.startTerminatorless(isLabel);
       this.print(label, node);
       this.endTerminatorless(terminatorState);
     }
@@ -170,10 +171,12 @@ export function TryStatement(node: Object) {
 export function CatchClause(node: Object) {
   this.word("catch");
   this.space();
-  this.token("(");
-  this.print(node.param, node);
-  this.token(")");
-  this.space();
+  if (node.param) {
+    this.token("(");
+    this.print(node.param, node);
+    this.token(")");
+    this.space();
+  }
   this.print(node.body, node);
 }
 
@@ -233,6 +236,12 @@ function constDeclarationIndent() {
 }
 
 export function VariableDeclaration(node: Object, parent: Object) {
+  if (node.declare) {
+    // TS
+    this.word("declare");
+    this.space();
+  }
+
   this.word(node.kind);
   this.space();
 
@@ -261,7 +270,10 @@ export function VariableDeclaration(node: Object, parent: Object) {
 
   let separator;
   if (hasInits) {
-    separator = node.kind === "const" ? constDeclarationIndent : variableDeclarationIndent;
+    separator =
+      node.kind === "const"
+        ? constDeclarationIndent
+        : variableDeclarationIndent;
   }
 
   //

packages/babel-generator/src/generators/tsFlowCommon.js

@@ -0,0 +1,38 @@
+export function TypeAnnotation(node) {
+  this.token(":");
+  this.space();
+  if (node.optional) this.token("?");
+  this.print(node.typeAnnotation, node);
+}
+
+export function TypeParameterInstantiation(node): void {
+  this.token("<");
+  this.printList(node.params, node, {});
+  this.token(">");
+}
+
+export { TypeParameterInstantiation as TypeParameterDeclaration };
+
+export function TypeParameter(node) {
+  this._variance(node);
+
+  this.word(node.name);
+
+  if (node.bound) {
+    this.print(node.bound, node);
+  }
+
+  if (node.constraint) {
+    this.space();
+    this.word("extends");
+    this.space();
+    this.print(node.constraint, node);
+  }
+
+  if (node.default) {
+    this.space();
+    this.token("=");
+    this.space();
+    this.print(node.default, node);
+  }
+}

packages/babel-generator/src/generators/types.js

@@ -10,9 +10,7 @@ export function RestElement(node: Object) {
   this.print(node.argument, node);
 }
 
-export {
-  RestElement as SpreadElement,
-};
+export { RestElement as SpreadElement };
 
 export function ObjectExpression(node: Object) {
   const props = node.properties;
@@ -33,7 +31,9 @@ export { ObjectExpression as ObjectPattern };
 
 export function ObjectMethod(node: Object) {
   this.printJoin(node.decorators, node);
-  this._method(node);
+  this._methodHead(node);
+  this.space();
+  this.print(node.body, node);
 }
 
 export function ObjectProperty(node: Object) {
@@ -45,8 +45,11 @@ export function ObjectProperty(node: Object) {
     this.token("]");
   } else {
     // print `({ foo: foo = 5 } = {})` as `({ foo = 5 } = {});`
-    if (t.isAssignmentPattern(node.value) && t.isIdentifier(node.key) &&
-      node.key.name === node.value.left.name) {
+    if (
+      t.isAssignmentPattern(node.value) &&
+      t.isIdentifier(node.key) &&
+      node.key.name === node.value.left.name
+    ) {
       this.print(node.value, node);
       return;
     }
@@ -54,10 +57,12 @@ export function ObjectProperty(node: Object) {
     this.print(node.key, node);
 
     // shorthand!
-    if (node.shorthand &&
+    if (
+      node.shorthand &&
       (t.isIdentifier(node.key) &&
-       t.isIdentifier(node.value) &&
-       node.key.name === node.value.name)) {
+        t.isIdentifier(node.value) &&
+        node.key.name === node.value.name)
+    ) {
       return;
     }
   }
@@ -111,7 +116,7 @@ export function NumericLiteral(node: Object) {
   const raw = this.getPossibleRaw(node);
   const value = node.value + "";
   if (raw == null) {
-    this.number(value);  // normalize
+    this.number(value); // normalize
   } else if (this.format.minified) {
     this.number(raw.length < value.length ? raw : value);
   } else {

packages/babel-generator/src/generators/typescript.js

@@ -0,0 +1,456 @@
+export function TSParameterProperty(node) {
+  if (node.accessibility) {
+    this.word(node.accessibility);
+    this.space();
+  }
+
+  if (node.readonly) {
+    this.word("readonly");
+    this.space();
+  }
+
+  this._param(node.parameter);
+}
+
+export function TSDeclareFunction(node) {
+  if (node.declare) {
+    this.word("declare");
+    this.space();
+  }
+  this._functionHead(node);
+  this.token(";");
+}
+
+export function TSDeclareMethod(node) {
+  this._classMethodHead(node);
+  this.token(";");
+}
+
+export function TSQualifiedName(node) {
+  this.print(node.left, node);
+  this.token(".");
+  this.print(node.right, node);
+}
+
+export function TSCallSignatureDeclaration(node) {
+  this.tsPrintSignatureDeclarationBase(node);
+}
+
+export function TSConstructSignatureDeclaration(node) {
+  this.word("new");
+  this.space();
+  this.tsPrintSignatureDeclarationBase(node);
+}
+
+export function TSPropertySignature(node) {
+  const { readonly, initializer } = node;
+  if (readonly) {
+    this.word("readonly");
+    this.space();
+  }
+  this.tsPrintPropertyOrMethodName(node);
+  this.print(node.typeAnnotation, node);
+  if (initializer) {
+    this.space();
+    this.token("=");
+    this.space();
+    this.print(initializer, node);
+  }
+  this.token(";");
+}
+
+export function tsPrintPropertyOrMethodName(node) {
+  if (node.computed) {
+    this.token("[");
+  }
+  this.print(node.key, node);
+  if (node.computed) {
+    this.token("]");
+  }
+  if (node.optional) {
+    this.token("?");
+  }
+}
+
+export function TSMethodSignature(node) {
+  this.tsPrintPropertyOrMethodName(node);
+  this.tsPrintSignatureDeclarationBase(node);
+  this.token(";");
+}
+
+export function TSIndexSignature(node) {
+  const { readonly } = node;
+  if (readonly) {
+    this.word("readonly");
+    this.space();
+  }
+  this.token("[");
+  this._parameters(node.parameters, node);
+  this.token("]");
+  this.print(node.typeAnnotation, node);
+  this.token(";");
+}
+
+export function TSAnyKeyword() {
+  this.word("any");
+}
+export function TSNumberKeyword() {
+  this.word("number");
+}
+export function TSObjectKeyword() {
+  this.word("object");
+}
+export function TSBooleanKeyword() {
+  this.word("boolean");
+}
+export function TSStringKeyword() {
+  this.word("string");
+}
+export function TSSymbolKeyword() {
+  this.word("symbol");
+}
+export function TSVoidKeyword() {
+  this.word("void");
+}
+export function TSUndefinedKeyword() {
+  this.word("undefined");
+}
+export function TSNullKeyword() {
+  this.word("null");
+}
+export function TSNeverKeyword() {
+  this.word("never");
+}
+
+export function TSThisType() {
+  this.word("this");
+}
+
+export function TSFunctionType(node) {
+  this.tsPrintFunctionOrConstructorType(node);
+}
+
+export function TSConstructorType(node) {
+  this.word("new");
+  this.space();
+  this.tsPrintFunctionOrConstructorType(node);
+}
+
+export function tsPrintFunctionOrConstructorType(
+  node: FunctionOrConstructorType,
+) {
+  const { typeParameters, parameters } = node;
+  this.print(typeParameters, node);
+  this.token("(");
+  this._parameters(parameters, node);
+  this.token(")");
+  this.space();
+  this.token("=>");
+  this.space();
+  this.print(node.typeAnnotation.typeAnnotation, node);
+}
+
+export function TSTypeReference(node) {
+  this.print(node.typeName, node);
+  this.print(node.typeParameters, node);
+}
+
+export function TSTypePredicate(node) {
+  this.print(node.parameterName);
+  this.space();
+  this.word("is");
+  this.space();
+  this.print(node.typeAnnotation.typeAnnotation);
+}
+
+export function TSTypeQuery(node) {
+  this.word("typeof");
+  this.space();
+  this.print(node.exprName);
+}
+
+export function TSTypeLiteral(node) {
+  this.tsPrintTypeLiteralOrInterfaceBody(node.members, node);
+}
+
+export function tsPrintTypeLiteralOrInterfaceBody(members, node) {
+  this.tsPrintBraced(members, node);
+}
+
+export function tsPrintBraced(members, node) {
+  this.token("{");
+  if (members.length) {
+    this.indent();
+    this.newline();
+    for (const member of members) {
+      this.print(member, node);
+      //this.token(sep);
+      this.newline();
+    }
+    this.dedent();
+    this.rightBrace();
+  } else {
+    this.token("}");
+  }
+}
+
+export function TSArrayType(node) {
+  this.print(node.elementType);
+  this.token("[]");
+}
+
+export function TSTupleType(node) {
+  this.token("[");
+  this.printList(node.elementTypes, node);
+  this.token("]");
+}
+
+export function TSUnionType(node) {
+  this.tsPrintUnionOrIntersectionType(node, "|");
+}
+
+export function TSIntersectionType(node) {
+  this.tsPrintUnionOrIntersectionType(node, "&");
+}
+
+export function tsPrintUnionOrIntersectionType(node, sep) {
+  this.printJoin(node.types, node, {
+    separator() {
+      this.space();
+      this.token(sep);
+      this.space();
+    },
+  });
+}
+
+export function TSParenthesizedType(node) {
+  this.token("(");
+  this.print(node.typeAnnotation, node);
+  this.token(")");
+}
+
+export function TSTypeOperator(node) {
+  this.token(node.operator);
+  this.space();
+  this.print(node.typeAnnotation, node);
+}
+
+export function TSIndexedAccessType(node) {
+  this.print(node.objectType, node);
+  this.token("[");
+  this.print(node.indexType, node);
+  this.token("]");
+}
+
+export function TSMappedType(node) {
+  const { readonly, typeParameter, optional } = node;
+  this.token("{");
+  this.space();
+  if (readonly) {
+    this.word("readonly");
+    this.space();
+  }
+
+  this.token("[");
+  this.word(typeParameter.name);
+  this.space();
+  this.word("in");
+  this.space();
+  this.print(typeParameter.constraint, typeParameter);
+  this.token("]");
+
+  if (optional) {
+    this.token("?");
+  }
+  this.token(":");
+  this.space();
+  this.print(node.typeAnnotation, node);
+  this.space();
+  this.token("}");
+}
+
+export function TSLiteralType(node) {
+  this.print(node.literal, node);
+}
+
+export function TSExpressionWithTypeArguments(node) {
+  this.print(node.expression, node);
+  this.print(node.typeParameters, node);
+}
+
+export function TSInterfaceDeclaration(node) {
+  const { declare, id, typeParameters, extends: extendz, body } = node;
+  if (declare) {
+    this.word("declare");
+    this.space();
+  }
+  this.word("interface");
+  this.space();
+  this.print(id, node);
+  this.print(typeParameters, node);
+  if (extendz) {
+    this.space();
+    this.word("extends");
+    this.space();
+    this.printList(extendz, node);
+  }
+  this.space();
+  this.print(body, node);
+}
+
+export function TSInterfaceBody(node) {
+  this.tsPrintTypeLiteralOrInterfaceBody(node.body, node);
+}
+
+export function TSTypeAliasDeclaration(node) {
+  const { declare, id, typeParameters, typeAnnotation } = node;
+  if (declare) {
+    this.word("declare");
+    this.space();
+  }
+  this.word("type");
+  this.space();
+  this.print(id, node);
+  this.print(typeParameters, node);
+  this.space();
+  this.token("=");
+  this.space();
+  this.print(typeAnnotation, node);
+  this.token(";");
+}
+
+export function TSAsExpression(node) {
+  const { expression, typeAnnotation } = node;
+  this.print(expression, node);
+  this.space();
+  this.word("as");
+  this.space();
+  this.print(typeAnnotation, node);
+}
+
+export function TSTypeAssertion(node) {
+  const { typeAnnotation, expression } = node;
+  this.token("<");
+  this.print(typeAnnotation, node);
+  this.token(">");
+  this.space();
+  this.print(expression, node);
+}
+
+export function TSEnumDeclaration(node) {
+  const { declare, const: isConst, id, members } = node;
+  if (declare) {
+    this.word("declare");
+    this.space();
+  }
+  if (isConst) {
+    this.word("const");
+    this.space();
+  }
+  this.word("enum");
+  this.space();
+  this.print(id, node);
+  this.space();
+  this.tsPrintBraced(members, node);
+}
+
+export function TSEnumMember(node) {
+  const { id, initializer } = node;
+  this.print(id, node);
+  if (initializer) {
+    this.space();
+    this.token("=");
+    this.space();
+    this.print(initializer, node);
+  }
+  this.token(",");
+}
+
+export function TSModuleDeclaration(node) {
+  const { declare, id } = node;
+
+  if (declare) {
+    this.word("declare");
+    this.space();
+  }
+
+  if (!node.global) {
+    this.word(id.type === "Identifier" ? "namespace" : "module");
+    this.space();
+  }
+  this.print(id, node);
+
+  if (!node.body) {
+    this.token(";");
+    return;
+  }
+
+  let body = node.body;
+  while (body.type === "TSModuleDeclaration") {
+    this.token(".");
+    this.print(body.id, body);
+    body = body.body;
+  }
+
+  this.space();
+  this.print(body, node);
+}
+
+export function TSModuleBlock(node) {
+  this.tsPrintBraced(node.body, node);
+}
+
+export function TSImportEqualsDeclaration(node) {
+  const { isExport, id, moduleReference } = node;
+  if (isExport) {
+    this.word("export");
+    this.space();
+  }
+  this.word("import");
+  this.space();
+  this.print(id, node);
+  this.space();
+  this.token("=");
+  this.space();
+  this.print(moduleReference, node);
+  this.token(";");
+}
+
+export function TSExternalModuleReference(node) {
+  this.token("require(");
+  this.print(node.expression, node);
+  this.token(")");
+}
+
+export function TSNonNullExpression(node) {
+  this.print(node.expression, node);
+  this.token("!");
+}
+
+export function TSExportAssignment(node) {
+  this.word("export");
+  this.space();
+  this.token("=");
+  this.space();
+  this.print(node.expression, node);
+  this.token(";");
+}
+
+export function TSNamespaceExportDeclaration(node) {
+  this.word("export");
+  this.space();
+  this.word("as");
+  this.space();
+  this.word("namespace");
+  this.space();
+  this.print(node.id, node);
+}
+
+export function tsPrintSignatureDeclarationBase(node) {
+  const { typeParameters, parameters } = node;
+  this.print(typeParameters, node);
+  this.token("(");
+  this._parameters(parameters, node);
+  this.token(")");
+  this.print(node.typeAnnotation, node);
+}

packages/babel-generator/src/index.js

@@ -1,8 +1,6 @@
-import detectIndent from "detect-indent";
 import SourceMap from "./source-map";
 import * as messages from "babel-messages";
-import Printer from "./printer";
-import type { Format } from "./printer";
+import Printer, { type Format } from "./printer";
 
 /**
  * Babel's code generator, turns an ast into code, maintaining sourcemaps,
@@ -11,10 +9,9 @@ import type { Format } from "./printer";
 
 class Generator extends Printer {
   constructor(ast, opts = {}, code) {
-    const tokens = ast.tokens || [];
-    const format = normalizeOptions(code, opts, tokens);
+    const format = normalizeOptions(code, opts);
     const map = opts.sourceMaps ? new SourceMap(opts, code) : null;
-    super(format, map, tokens);
+    super(format, map);
 
     this.ast = ast;
   }
@@ -39,13 +36,7 @@ class Generator extends Printer {
  * - If `opts.compact = "auto"` and the code is over 500KB, `compact` will be set to `true`.
  */
 
-function normalizeOptions(code, opts, tokens): Format {
-  let style = "  ";
-  if (code && typeof code === "string") {
-    const indent = detectIndent(code).indent;
-    if (indent && indent !== " ") style = indent;
-  }
-
+function normalizeOptions(code, opts): Format {
   const format = {
     auxiliaryCommentBefore: opts.auxiliaryCommentBefore,
     auxiliaryCommentAfter: opts.auxiliaryCommentAfter,
@@ -56,11 +47,11 @@ function normalizeOptions(code, opts, tokens): Format {
     compact: opts.compact,
     minified: opts.minified,
     concise: opts.concise,
-    quotes: findCommonStringDelimiter(code, tokens),
+    quotes: "double",
     jsonCompatibleStrings: opts.jsonCompatibleStrings,
     indent: {
       adjustMultilineComment: true,
-      style: style,
+      style: "  ",
       base: 0,
     },
   };
@@ -68,17 +59,23 @@ function normalizeOptions(code, opts, tokens): Format {
   if (format.minified) {
     format.compact = true;
 
-    format.shouldPrintComment = format.shouldPrintComment || (() => format.comments);
+    format.shouldPrintComment =
+      format.shouldPrintComment || (() => format.comments);
   } else {
-    format.shouldPrintComment = format.shouldPrintComment || ((value) => format.comments ||
-      (value.indexOf("@license") >= 0 || value.indexOf("@preserve") >= 0));
+    format.shouldPrintComment =
+      format.shouldPrintComment ||
+      (value =>
+        format.comments ||
+        (value.indexOf("@license") >= 0 || value.indexOf("@preserve") >= 0));
   }
 
   if (format.compact === "auto") {
-    format.compact = code.length > 500000; // 500KB
+    format.compact = code.length > 500_000; // 500KB
 
     if (format.compact) {
-      console.error("[BABEL] " + messages.get("codeGeneratorDeopt", opts.filename, "500KB"));
+      console.error(
+        "[BABEL] " + messages.get("codeGeneratorDeopt", opts.filename, "500KB"),
+      );
     }
   }
 
@@ -89,43 +86,6 @@ function normalizeOptions(code, opts, tokens): Format {
   return format;
 }
 
-/**
- * Determine if input code uses more single or double quotes.
- */
-function findCommonStringDelimiter(code, tokens) {
-  const DEFAULT_STRING_DELIMITER = "double";
-  if (!code) {
-    return DEFAULT_STRING_DELIMITER;
-  }
-
-  const occurences = {
-    single: 0,
-    double: 0,
-  };
-
-  let checked = 0;
-
-  for (let i = 0; i < tokens.length; i++) {
-    const token = tokens[i];
-    if (token.type.label !== "string") continue;
-
-    const raw = code.slice(token.start, token.end);
-    if (raw[0] === "'") {
-      occurences.single++;
-    } else {
-      occurences.double++;
-    }
-
-    checked++;
-    if (checked >= 3) break;
-  }
-  if (occurences.single > occurences.double) {
-    return "single";
-  } else {
-    return "double";
-  }
-}
-
 /**
  * We originally exported the Generator class above, but to make it extra clear that it is a private API,
  * we have moved that to an internal class instance and simplified the interface to the two public methods
@@ -141,7 +101,7 @@ export class CodeGenerator {
   }
 }
 
-export default function (ast: Object, opts: Object, code: string): Object {
+export default function(ast: Object, opts: Object, code: string): Object {
   const gen = new Generator(ast, opts, code);
   return gen.generate();
 }

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

@@ -7,15 +7,16 @@ function expandAliases(obj) {
 
   function add(type, func) {
     const fn = newObj[type];
-    newObj[type] = fn ? function(node, parent, stack) {
-      const result = fn(node, parent, stack);
+    newObj[type] = fn
+      ? function(node, parent, stack) {
+          const result = fn(node, parent, stack);
 
-      return result == null ? func(node, parent, stack) : result;
-    } : func;
+          return result == null ? func(node, parent, stack) : result;
+        }
+      : func;
   }
 
   for (const type of Object.keys(obj)) {
-
     const aliases = t.FLIPPED_ALIAS_KEYS[type];
     if (aliases) {
       for (const alias of aliases) {
@@ -46,8 +47,10 @@ function isOrHasCallExpression(node) {
   }
 
   if (t.isMemberExpression(node)) {
-    return isOrHasCallExpression(node.object) ||
-      (!node.computed && isOrHasCallExpression(node.property));
+    return (
+      isOrHasCallExpression(node.object) ||
+      (!node.computed && isOrHasCallExpression(node.property))
+    );
   } else {
     return false;
   }

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

@@ -38,17 +38,33 @@ export function UpdateExpression(node: Object, parent: Object): boolean {
   return t.isMemberExpression(parent) && parent.object === node;
 }
 
-export function ObjectExpression(node: Object, parent: Object, printStack: Array<Object>): boolean {
+export function ObjectExpression(
+  node: Object,
+  parent: Object,
+  printStack: Array<Object>,
+): boolean {
   return isFirstInStatement(printStack, { considerArrow: true });
 }
 
-export function DoExpression(node: Object, parent: Object, printStack: Array<Object>): boolean {
+export function DoExpression(
+  node: Object,
+  parent: Object,
+  printStack: Array<Object>,
+): boolean {
   return isFirstInStatement(printStack);
 }
 
 export function Binary(node: Object, parent: Object): boolean {
   if (
-    ((t.isCallExpression(parent) || t.isNewExpression(parent)) && parent.callee === node) ||
+    node.operator === "**" &&
+    t.isBinaryExpression(parent, { operator: "**" })
+  ) {
+    return parent.left === node;
+  }
+
+  if (
+    ((t.isCallExpression(parent) || t.isNewExpression(parent)) &&
+      parent.callee === node) ||
     t.isUnaryLike(parent) ||
     (t.isMemberExpression(parent) && parent.object === node) ||
     t.isAwaitExpression(parent)
@@ -65,7 +81,9 @@ export function Binary(node: Object, parent: Object): boolean {
 
     if (
       // Logical expressions with the same precedence don't need parens.
-      (parentPos === nodePos && parent.right === node && !t.isLogicalExpression(parent)) ||
+      (parentPos === nodePos &&
+        parent.right === node &&
+        !t.isLogicalExpression(parent)) ||
       parentPos > nodePos
     ) {
       return true;
@@ -75,14 +93,24 @@ export function Binary(node: Object, parent: Object): boolean {
   return false;
 }
 
+export function TSAsExpression() {
+  return true;
+}
+
+export function TSTypeAssertion() {
+  return true;
+}
+
 export function BinaryExpression(node: Object, parent: Object): boolean {
   // let i = (1 in []);
   // for ((1 in []);;);
-  return node.operator === "in" && (t.isVariableDeclarator(parent) || t.isFor(parent));
+  return (
+    node.operator === "in" &&
+    (t.isVariableDeclarator(parent) || t.isFor(parent))
+  );
 }
 
 export function SequenceExpression(node: Object, parent: Object): boolean {
-
   if (
     // Although parentheses wouldn"t hurt around sequence
     // expressions in the head of for loops, traditional style
@@ -106,44 +134,45 @@ export function SequenceExpression(node: Object, parent: Object): boolean {
 }
 
 export function YieldExpression(node: Object, parent: Object): boolean {
-  return t.isBinary(parent) ||
-         t.isUnaryLike(parent) ||
-         t.isCallExpression(parent) ||
-         t.isMemberExpression(parent) ||
-         t.isNewExpression(parent) ||
-         (t.isConditionalExpression(parent) && node === parent.test);
-
+  return (
+    t.isBinary(parent) ||
+    t.isUnaryLike(parent) ||
+    t.isCallExpression(parent) ||
+    t.isMemberExpression(parent) ||
+    t.isNewExpression(parent) ||
+    (t.isConditionalExpression(parent) && node === parent.test)
+  );
 }
 
 export { YieldExpression as AwaitExpression };
 
-export function ClassExpression(node: Object, parent: Object, printStack: Array<Object>): boolean {
+export function ClassExpression(
+  node: Object,
+  parent: Object,
+  printStack: Array<Object>,
+): boolean {
   return isFirstInStatement(printStack, { considerDefaultExports: true });
 }
 
 export function UnaryLike(node: Object, parent: Object): boolean {
-  return t.isMemberExpression(parent, { object: node }) ||
-         t.isCallExpression(parent, { callee: node }) ||
-         t.isNewExpression(parent, { callee: node });
+  return (
+    t.isMemberExpression(parent, { object: node }) ||
+    t.isCallExpression(parent, { callee: node }) ||
+    t.isNewExpression(parent, { callee: node }) ||
+    t.isBinaryExpression(parent, { operator: "**", left: node })
+  );
 }
 
-export function FunctionExpression(node: Object, parent: Object, printStack: Array<Object>): boolean {
+export function FunctionExpression(
+  node: Object,
+  parent: Object,
+  printStack: Array<Object>,
+): boolean {
   return isFirstInStatement(printStack, { considerDefaultExports: true });
 }
 
 export function ArrowFunctionExpression(node: Object, parent: Object): boolean {
-  if (
-    // export default (function () {});
-    t.isExportDeclaration(parent) ||
-    t.isBinaryExpression(parent) ||
-    t.isLogicalExpression(parent) ||
-    t.isUnaryExpression(parent) ||
-    t.isTaggedTemplateExpression(parent)
-  ) {
-    return true;
-  }
-
-  return UnaryLike(node, parent);
+  return t.isExportDeclaration(parent) || ConditionalExpression(node, parent);
 }
 
 export function ConditionalExpression(node: Object, parent: Object): boolean {
@@ -151,7 +180,10 @@ export function ConditionalExpression(node: Object, parent: Object): boolean {
     t.isUnaryLike(parent) ||
     t.isBinary(parent) ||
     t.isConditionalExpression(parent, { test: node }) ||
-    t.isAwaitExpression(parent)
+    t.isAwaitExpression(parent) ||
+    t.isTaggedTemplateExpression(parent) ||
+    t.isTSTypeAssertion(parent) ||
+    t.isTSAsExpression(parent)
   ) {
     return true;
   }
@@ -169,10 +201,10 @@ export function AssignmentExpression(node: Object): boolean {
 
 // Walk up the print stack to deterimine if our node can come first
 // in statement.
-function isFirstInStatement(printStack: Array<Object>, {
-    considerArrow = false,
-    considerDefaultExports = false,
-  } = {}): boolean {
+function isFirstInStatement(
+  printStack: Array<Object>,
+  { considerArrow = false, considerDefaultExports = false } = {},
+): boolean {
   let i = printStack.length - 1;
   let node = printStack[i];
   i--;
@@ -181,8 +213,9 @@ function isFirstInStatement(printStack: Array<Object>, {
     if (
       t.isExpressionStatement(parent, { expression: node }) ||
       t.isTaggedTemplateExpression(parent) ||
-      considerDefaultExports && t.isExportDefaultDeclaration(parent, { declaration: node }) ||
-      considerArrow && t.isArrowFunctionExpression(parent, { body: node })
+      (considerDefaultExports &&
+        t.isExportDefaultDeclaration(parent, { declaration: node })) ||
+      (considerArrow && t.isArrowFunctionExpression(parent, { body: node }))
     ) {
       return true;
     }

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

@@ -3,7 +3,7 @@ import * as t from "babel-types";
 
 type WhitespaceObject = {
   before?: boolean,
-  after?: boolean
+  after?: boolean,
 };
 
 /**
@@ -45,15 +45,22 @@ function isHelper(node) {
   } else if (t.isCallExpression(node)) {
     return isHelper(node.callee);
   } else if (t.isBinary(node) || t.isAssignmentExpression(node)) {
-    return (t.isIdentifier(node.left) && isHelper(node.left)) || isHelper(node.right);
+    return (
+      (t.isIdentifier(node.left) && isHelper(node.left)) || isHelper(node.right)
+    );
   } else {
     return false;
   }
 }
 
 function isType(node) {
-  return t.isLiteral(node) || t.isObjectExpression(node) || t.isArrayExpression(node) ||
-         t.isIdentifier(node) || t.isMemberExpression(node);
+  return (
+    t.isLiteral(node) ||
+    t.isObjectExpression(node) ||
+    t.isArrayExpression(node) ||
+    t.isIdentifier(node) ||
+    t.isMemberExpression(node)
+  );
 }
 
 /**
@@ -61,7 +68,6 @@ function isType(node) {
  */
 
 export const nodes = {
-
   /**
    * Test if AssignmentExpression needs whitespace.
    */
@@ -80,9 +86,12 @@ export const nodes = {
    * Test if SwitchCase needs whitespace.
    */
 
-  SwitchCase(node: Object, parent: Object): ?WhitespaceObject {
+  SwitchCase(node: Object, parent: Object): WhitespaceObject {
     return {
       before: node.consequent.length || parent.cases[0] === node,
+      after:
+        !node.consequent.length &&
+        parent.cases[parent.cases.length - 1] === node,
     };
   },
 
@@ -164,9 +173,10 @@ export const nodes = {
  * Test if Property needs whitespace.
  */
 
-nodes.ObjectProperty =
-nodes.ObjectTypeProperty =
-nodes.ObjectMethod = function (node: Object, parent): ?WhitespaceObject {
+nodes.ObjectProperty = nodes.ObjectTypeProperty = nodes.ObjectMethod = function(
+  node: Object,
+  parent,
+): ?WhitespaceObject {
   if (parent.properties[0] === node) {
     return {
       before: true,
@@ -174,12 +184,37 @@ nodes.ObjectMethod = function (node: Object, parent): ?WhitespaceObject {
   }
 };
 
+nodes.ObjectTypeCallProperty = function(
+  node: Object,
+  parent,
+): ?WhitespaceObject {
+  if (
+    parent.callProperties[0] === node &&
+    (!parent.properties || !parent.properties.length)
+  ) {
+    return {
+      before: true,
+    };
+  }
+};
+
+nodes.ObjectTypeIndexer = function(node: Object, parent): ?WhitespaceObject {
+  if (
+    parent.indexers[0] === node &&
+    (!parent.properties || !parent.properties.length) &&
+    (!parent.callProperties || !parent.callProperties.length)
+  ) {
+    return {
+      before: true,
+    };
+  }
+};
+
 /**
  * Returns lists from node types that need whitespace.
  */
 
 export const list = {
-
   /**
    * Return VariableDeclaration declarations init properties.
    */
@@ -216,12 +251,12 @@ export const list = {
   ["LabeledStatement", true],
   ["SwitchStatement", true],
   ["TryStatement", true],
-].forEach(function ([type, amounts]) {
+].forEach(function([type, amounts]) {
   if (typeof amounts === "boolean") {
     amounts = { after: amounts, before: amounts };
   }
-  [type].concat(t.FLIPPED_ALIAS_KEYS[type] || []).forEach(function (type) {
-    nodes[type] = function () {
+  [type].concat(t.FLIPPED_ALIAS_KEYS[type] || []).forEach(function(type) {
+    nodes[type] = function() {
       return amounts;
     };
   });

packages/babel-generator/src/printer.js

@@ -1,10 +1,7 @@
-import find from "lodash/find";
-import findLast from "lodash/findLast";
 import isInteger from "lodash/isInteger";
 import repeat from "lodash/repeat";
 import Buffer from "./buffer";
 import * as n from "./node";
-import Whitespace from "./whitespace";
 import * as t from "babel-types";
 
 import * as generatorFunctions from "./generators";
@@ -14,40 +11,39 @@ const ZERO_DECIMAL_INTEGER = /\.0+$/;
 const NON_DECIMAL_LITERAL = /^0[box]/;
 
 export type Format = {
-  shouldPrintComment: (comment: string) => boolean;
-  retainLines: boolean;
-  retainFunctionParens: boolean;
-  comments: boolean;
-  auxiliaryCommentBefore: string;
-  auxiliaryCommentAfter: string;
-  compact: boolean | "auto";
-  minified: boolean;
-  quotes: "single" | "double";
-  concise: boolean;
+  shouldPrintComment: (comment: string) => boolean,
+  retainLines: boolean,
+  retainFunctionParens: boolean,
+  comments: boolean,
+  auxiliaryCommentBefore: string,
+  auxiliaryCommentAfter: string,
+  compact: boolean | "auto",
+  minified: boolean,
+  quotes: "single" | "double",
+  concise: boolean,
   indent: {
-    adjustMultilineComment: boolean;
-    style: string;
-    base: number;
-  }
+    adjustMultilineComment: boolean,
+    style: string,
+    base: number,
+  },
 };
 
 export default class Printer {
-  constructor(format, map, tokens) {
+  constructor(format, map) {
     this.format = format || {};
     this._buf = new Buffer(map);
-    this._whitespace = tokens.length > 0 ? new Whitespace(tokens) : null;
   }
 
   format: Format;
   inForStatementInitCounter: number = 0;
 
   _buf: Buffer;
-  _whitespace: Whitespace;
   _printStack: Array<Node> = [];
   _indent: number = 0;
   _insideAux: boolean = false;
   _printedCommentStarts: Object = {};
   _parenPushNewlineState: ?Object = null;
+  _noLineTerminator: boolean = false;
   _printAuxAfterOnNextUserNode: boolean = false;
   _printedComments: WeakSet = new WeakSet();
   _endsWithInteger = false;
@@ -107,7 +103,10 @@ export default class Printer {
   space(force: boolean = false): void {
     if (this.format.compact) return;
 
-    if ((this._buf.hasContent() && !this.endsWith(" ") && !this.endsWith("\n")) || force) {
+    if (
+      (this._buf.hasContent() && !this.endsWith(" ") && !this.endsWith("\n")) ||
+      force
+    ) {
       this._space();
     }
   }
@@ -149,14 +148,14 @@ export default class Printer {
   token(str: string): void {
     // space is mandatory to avoid outputting <!--
     // http://javascript.spec.whatwg.org/#comment-syntax
-    if ((str === "--" && this.endsWith("!")) ||
-
+    if (
+      (str === "--" && this.endsWith("!")) ||
       // Need spaces for operators of the same kind to avoid: `a+++b`
       (str[0] === "+" && this.endsWith("+")) ||
       (str[0] === "-" && this.endsWith("-")) ||
-
       // Needs spaces to avoid changing '34' to '34.', which would still be a valid number.
-      (str[0] === "." && this._endsWithInteger)) {
+      (str[0] === "." && this._endsWithInteger)
+    ) {
       this._space();
     }
 
@@ -283,7 +282,7 @@ export default class Printer {
    *
    * This is to prevent breaking semantics for terminatorless separator nodes. eg:
    *
-   *    return foo;
+   *   return foo;
    *
    * returns `foo`. But if we do:
    *
@@ -293,10 +292,15 @@ export default class Printer {
    *  `undefined` will be returned and not `foo` due to the terminator.
    */
 
-  startTerminatorless(): Object {
-    return this._parenPushNewlineState = {
-      printed: false,
-    };
+  startTerminatorless(isLabel: boolean = false): Object {
+    if (isLabel) {
+      this._noLineTerminator = true;
+      return null;
+    } else {
+      return (this._parenPushNewlineState = {
+        printed: false,
+      });
+    }
   }
 
   /**
@@ -304,7 +308,8 @@ export default class Printer {
    */
 
   endTerminatorless(state: Object) {
-    if (state.printed) {
+    this._noLineTerminator = false;
+    if (state && state.printed) {
       this.dedent();
       this.newline();
       this.token(")");
@@ -321,8 +326,11 @@ export default class Printer {
 
     const printMethod = this[node.type];
     if (!printMethod) {
-      // eslint-disable-next-line max-len
-      throw new ReferenceError(`unknown node of type ${JSON.stringify(node.type)} with constructor ${JSON.stringify(node && node.constructor.name)}`);
+      throw new ReferenceError(
+        `unknown node of type ${JSON.stringify(
+          node.type,
+        )} with constructor ${JSON.stringify(node && node.constructor.name)}`,
+      );
     }
 
     this._printStack.push(node);
@@ -335,7 +343,8 @@ export default class Printer {
     if (
       this.format.retainFunctionParens &&
       node.type === "FunctionExpression" &&
-      node.extra && node.extra.parenthesized
+      node.extra &&
+      node.extra.parenthesized
     ) {
       needsParens = true;
     }
@@ -343,7 +352,7 @@ export default class Printer {
 
     this._printLeadingComments(node, parent);
 
-    const loc = (t.isProgram(node) || t.isFile(node)) ? null : node.loc;
+    const loc = t.isProgram(node) || t.isFile(node) ? null : node.loc;
     this.withSource("start", loc, () => {
       this[node.type](node, parent);
     });
@@ -392,7 +401,12 @@ export default class Printer {
 
   getPossibleRaw(node) {
     const extra = node.extra;
-    if (extra && extra.raw != null && extra.rawValue != null && node.value === extra.rawValue) {
+    if (
+      extra &&
+      extra.raw != null &&
+      extra.rawValue != null &&
+      node.value === extra.rawValue
+    ) {
       return extra.raw;
     }
   }
@@ -485,33 +499,13 @@ export default class Printer {
     }
 
     let lines = 0;
-
-    if (node.start != null && !node._ignoreUserWhitespace && this._whitespace) {
-      // user node
-      if (leading) {
-        const comments = node.leadingComments;
-        const comment = comments && find(comments, (comment) =>
-          !!comment.loc && this.format.shouldPrintComment(comment.value));
-
-        lines = this._whitespace.getNewlinesBefore(comment || node);
-      } else {
-        const comments = node.trailingComments;
-        const comment = comments && findLast(comments, (comment) =>
-          !!comment.loc && this.format.shouldPrintComment(comment.value));
-
-        lines = this._whitespace.getNewlinesAfter(comment || node);
-      }
-    } else {
-      // generated node
+    // don't add newlines at the beginning of the file
+    if (this._buf.hasContent()) {
       if (!leading) lines++; // always include at least a single line after
       if (opts.addNewlines) lines += opts.addNewlines(leading, node) || 0;
 
-      let needs = n.needsWhitespaceAfter;
-      if (leading) needs = n.needsWhitespaceBefore;
+      const needs = leading ? n.needsWhitespaceBefore : n.needsWhitespaceAfter;
       if (needs(node, parent)) lines++;
-
-      // generated nodes can't add starting file whitespace
-      if (!this._buf.hasContent()) lines = 0;
     }
 
     this.newline(lines);
@@ -520,7 +514,9 @@ export default class Printer {
   _getComments(leading, node) {
     // Note, we use a boolean flag here instead of passing in the attribute name as it is faster
     // because this is called extremely frequently.
-    return (node && (leading ? node.leadingComments : node.trailingComments)) || [];
+    return (
+      (node && (leading ? node.leadingComments : node.trailingComments)) || []
+    );
   }
 
   _printComment(comment) {
@@ -538,22 +534,33 @@ export default class Printer {
       this._printedCommentStarts[comment.start] = true;
     }
 
-    // whitespace before
-    this.newline(this._whitespace ? this._whitespace.getNewlinesBefore(comment) : 0);
+    const isBlockComment = comment.type === "CommentBlock";
+
+    // Always add a newline before a block comment
+    this.newline(
+      this._buf.hasContent() && !this._noLineTerminator && isBlockComment
+        ? 1
+        : 0,
+    );
 
     if (!this.endsWith("[") && !this.endsWith("{")) this.space();
 
-    let val = comment.type === "CommentLine" ? `//${comment.value}\n` : `/*${comment.value}*/`;
+    let val =
+      !isBlockComment && !this._noLineTerminator
+        ? `//${comment.value}\n`
+        : `/*${comment.value}*/`;
 
-    //
-    if (comment.type === "CommentBlock" && this.format.indent.adjustMultilineComment) {
+    if (isBlockComment && this.format.indent.adjustMultilineComment) {
       const offset = comment.loc && comment.loc.start.column;
       if (offset) {
         const newlineRegex = new RegExp("\\n\\s{1," + offset + "}", "g");
         val = val.replace(newlineRegex, "\n");
       }
 
-      const indentSize = Math.max(this._getIndent().length, this._buf.getCurrentColumn());
+      const indentSize = Math.max(
+        this._getIndent().length,
+        this._buf.getCurrentColumn(),
+      );
       val = val.replace(/\n(?!$)/g, `\n${repeat(" ", indentSize)}`);
     }
 
@@ -564,10 +571,8 @@ export default class Printer {
       this._append(val);
     });
 
-    // whitespace after
-    this.newline((this._whitespace ? this._whitespace.getNewlinesAfter(comment) : 0) +
-      // Subtract one to account for the line force-added above.
-      (comment.type === "CommentLine" ? -1 : 0));
+    // Always add a newline after a block comment
+    this.newline(isBlockComment && !this._noLineTerminator ? 1 : 0);
   }
 
   _printComments(comments?: Array<Object>) {

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

@@ -18,16 +18,16 @@ export default class SourceMap {
 
   get() {
     if (!this._cachedMap) {
-      const map = this._cachedMap = new sourceMap.SourceMapGenerator({
+      const map = (this._cachedMap = new sourceMap.SourceMapGenerator({
         file: this._opts.sourceMapTarget,
         sourceRoot: this._opts.sourceRoot,
-      });
+      }));
 
       const code = this._code;
       if (typeof code === "string") {
         map.setSourceContent(this._opts.sourceFileName, code);
       } else if (typeof code === "object") {
-        Object.keys(code).forEach((sourceFileName) => {
+        Object.keys(code).forEach(sourceFileName => {
           map.setSourceContent(sourceFileName, code[sourceFileName]);
         });
       }
@@ -60,8 +60,11 @@ export default class SourceMap {
 
     // If this mapping points to the same source location as the last one, we can ignore it since
     // the previous one covers it.
-    if (this._lastGenLine === generatedLine && this._lastSourceLine === line &&
-      this._lastSourceColumn === column) {
+    if (
+      this._lastGenLine === generatedLine &&
+      this._lastSourceLine === line &&
+      this._lastSourceColumn === column
+    ) {
       return;
     }
 
@@ -80,10 +83,13 @@ export default class SourceMap {
         column: generatedColumn,
       },
       source: line == null ? undefined : filename || this._opts.sourceFileName,
-      original: line == null ? undefined : {
-        line: line,
-        column: column,
-      },
+      original:
+        line == null
+          ? undefined
+          : {
+              line: line,
+              column: column,
+            },
     });
   }
 }

packages/babel-generator/src/whitespace.js

@@ -1,92 +0,0 @@
-/**
- * Get whitespace around tokens.
- */
-
-export default class Whitespace {
-  constructor(tokens) {
-    this.tokens = tokens;
-    this.used = {};
-  }
-
-  /**
-   * Count all the newlines before a node.
-   */
-
-  getNewlinesBefore(node) {
-    let startToken;
-    let endToken;
-    const tokens = this.tokens;
-
-    let index = this._findToken((token) => token.start - node.start, 0, tokens.length);
-    if (index >= 0) {
-      while (index && node.start === tokens[index - 1].start) --index;
-      startToken = tokens[index - 1];
-      endToken = tokens[index];
-    }
-
-    return this._getNewlinesBetween(startToken, endToken);
-  }
-
-  /**
-   * Count all the newlines after a node.
-   */
-
-  getNewlinesAfter(node) {
-    let startToken;
-    let endToken;
-    const tokens = this.tokens;
-
-    let index = this._findToken((token) => token.end - node.end, 0, tokens.length);
-    if (index >= 0) {
-      while (index && node.end === tokens[index - 1].end) --index;
-      startToken = tokens[index];
-      endToken = tokens[index + 1];
-      if (endToken.type.label === ",") endToken = tokens[index + 2];
-    }
-
-    if (endToken && endToken.type.label === "eof") {
-      return 1;
-    } else {
-      return this._getNewlinesBetween(startToken, endToken);
-    }
-  }
-
-  /**
-   * Count all the newlines between two tokens.
-   */
-
-  _getNewlinesBetween(startToken, endToken) {
-    if (!endToken || !endToken.loc) return 0;
-
-    const start = startToken ? startToken.loc.end.line : 1;
-    const end = endToken.loc.start.line;
-    let lines = 0;
-
-    for (let line = start; line < end; line++) {
-      if (typeof this.used[line] === "undefined") {
-        this.used[line] = true;
-        lines++;
-      }
-    }
-
-    return lines;
-  }
-
-  /**
-   * Find a token between start and end.
-   */
-
-  _findToken(test: Function, start: number, end: number): number {
-    if (start >= end) return -1;
-    const middle = (start + end) >>> 1;
-    const match: number = test(this.tokens[middle]);
-    if (match < 0) {
-      return this._findToken(test, middle + 1, end);
-    } else if (match > 0) {
-      return this._findToken(test, start, middle);
-    } else if (match === 0) {
-      return middle;
-    }
-    return -1;
-  }
-}

packages/babel-generator/test/fixtures/auto-indentation/hard-tab/expected.js

@@ -1,6 +1,7 @@
 function foo() {
-	bar();
-	if (foo) {
-		bar();
-	}
-}
+  bar();
+
+  if (foo) {
+    bar();
+  }
+}

packages/babel-generator/test/fixtures/auto-indentation/soft-tab-2/expected.js

@@ -1,6 +1,7 @@
 function foo() {
   bar();
+
   if (foo) {
     bar();
   }
-}
+}

packages/babel-generator/test/fixtures/auto-indentation/soft-tab-4/expected.js

@@ -1,6 +1,7 @@
 function foo() {
+  bar();
+
+  if (foo) {
     bar();
-    if (foo) {
-        bar();
-    }
-}
+  }
+}

packages/babel-generator/test/fixtures/auto-string/double/expected.js

@@ -2,4 +2,4 @@ foo("foo");
 foo("foo\nlol");
 foo("foo\n\"lol");
 foo("foo\n\"'lol");
-foo("😂");
+foo("😂");

packages/babel-generator/test/fixtures/auto-string/jsx/expected.js

@@ -1,9 +1,9 @@
 var single = 'quotes';
 var outnumber = 'double';
 var moreSingleQuotesThanDouble = '!';
-
 React.createClass({
   render() {
     return <View multiple="attributes" attribute="If parent is JSX keep double quote" />;
   }
-});
+
+});

packages/babel-generator/test/fixtures/auto-string/jsx/options.json

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

packages/babel-generator/test/fixtures/auto-string/single/expected.js

@@ -2,4 +2,4 @@ foo('foo');
 foo('foo\nlol');
 foo('foo\n"lol');
 foo('foo\n"\'lol');
-foo('😂');
+foo('😂');

packages/babel-generator/test/fixtures/comments/2-space-multi-comment-with-space/expected.js

@@ -1,8 +1,6 @@
 function test() {
-
   /*
    * this is comment
    */
-
   var i = 20;
-}
+}

packages/babel-generator/test/fixtures/comments/2-space-multi-comment/expected.js

@@ -3,4 +3,4 @@ function test() {
    * this is comment
    */
   var i = 20;
-}
+}

packages/babel-generator/test/fixtures/comments/block-line-comment-with-concise-format/expected.js

@@ -1,2 +1,2 @@
 { print("hello"); // comment
-}
+}

packages/babel-generator/test/fixtures/comments/block-line-comment-with-retainlines-option/expected.js

@@ -1,4 +1,4 @@
 {
   print("hello");
   // comment
-}
+}

packages/babel-generator/test/fixtures/comments/block-line-comment/expected.js

@@ -1,4 +1,4 @@
 // Leading to block
 {
   print("hello");
-}
+}

packages/babel-generator/test/fixtures/comments/comment-only-with-space/expected.js

@@ -1,7 +1,6 @@
-
 // from #23
 
 /**/
 
 /*
-*/
+*/

packages/babel-generator/test/fixtures/comments/comment-only/expected.js

@@ -1,4 +1,6 @@
 // from #23
+
 /**/
+
 /*
-*/
+*/

packages/babel-generator/test/fixtures/comments/comment-statement-with-retainlines-option/expected.js

@@ -2,4 +2,4 @@
 print("hello");
 
 // comment2
-print("hello2");
+print("hello2");

packages/babel-generator/test/fixtures/comments/computed-property-comments-2/expected.js

@@ -3,9 +3,10 @@ var test = {
    * Before bracket init
    */
   ["a"]: "1",
-  [/*
-    * Inside bracket init
-    */
+  [
+  /*
+   * Inside bracket init
+   */
   "b"]: "2"
 },
-    ok = 42;
+    ok = 42;