Update prettier to v2 (#11579)

Co-authored-by: Nicolò Ribaudo <nicolo.ribaudo@gmail.com>

Gulpfile.js

@@ -33,7 +33,7 @@ function getIndexFromPackage(name) {
 }
 
 function compilationLogger() {
-  return through.obj(function(file, enc, callback) {
+  return through.obj(function (file, enc, callback) {
     fancyLog(`Compiling '${chalk.cyan(file.relative)}'...`);
     callback(null, file);
   });
@@ -48,7 +48,7 @@ function errorsLogger() {
 }
 
 function rename(fn) {
-  return through.obj(function(file, enc, callback) {
+  return through.obj(function (file, enc, callback) {
     file.path = fn(file);
     callback(null, file);
   });

babel.config.js

@@ -1,6 +1,6 @@
 "use strict";
 
-module.exports = function(api) {
+module.exports = function (api) {
   const env = api.env();
 
   const includeCoverage = process.env.BABEL_COVERAGE === "true";

codemods/babel-plugin-codemod-object-assign-to-object-spread/src/index.js

@@ -1,6 +1,6 @@
 import syntaxObjectRestSpread from "@babel/plugin-syntax-object-rest-spread";
 
-export default function({ types: t }) {
+export default function ({ types: t }) {
   return {
     inherits: syntaxObjectRestSpread,
 

codemods/babel-plugin-codemod-optional-catch-binding/src/index.js

@@ -1,6 +1,6 @@
 import syntaxOptionalCatchBinding from "@babel/plugin-syntax-optional-catch-binding";
 
-export default function({ types: t }) {
+export default function ({ types: t }) {
   return {
     inherits: syntaxOptionalCatchBinding,
 

eslint/babel-eslint-parser/src/analyze-scope.js

@@ -237,7 +237,7 @@ class Referencer extends OriginalReferencer {
         this._checkIdentifierOrVisit(name);
       }
     }
-    scope.__define = function() {
+    scope.__define = function () {
       return parentScope.__define.apply(parentScope, arguments);
     };
 

eslint/babel-eslint-parser/src/convert/index.js

@@ -2,7 +2,7 @@ import convertTokens from "./convertTokens";
 import convertComments from "./convertComments";
 import convertAST from "./convertAST";
 
-export default function(ast, code) {
+export default function (ast, code) {
   ast.tokens = convertTokens(ast.tokens, code);
   convertComments(ast.comments);
   convertAST(ast, code);

eslint/babel-eslint-parser/test/index.js

@@ -84,7 +84,7 @@ describe("Babel and Espree", () => {
   });
 
   describe("compatibility", () => {
-    it("should allow ast.analyze to be called without options", function() {
+    it("should allow ast.analyze to be called without options", function () {
       const ast = parseForESLint("`test`", {
         eslintScopeManager: true,
         eslintVisitorKeys: true,

eslint/babel-eslint-plugin/src/rules/semi.js

@@ -57,13 +57,13 @@ function report(context, node, missing) {
   if (!missing) {
     message = "Missing semicolon.";
     loc = loc.end;
-    fix = function(fixer) {
+    fix = function (fixer) {
       return fixer.insertTextAfter(lastToken, ";");
     };
   } else {
     message = "Extra semicolon.";
     loc = loc.start;
-    fix = function(fixer) {
+    fix = function (fixer) {
       return fixer.remove(lastToken);
     };
   }

eslint/babel-eslint-plugin/test/rules/no-invalid-this.js

@@ -50,8 +50,8 @@ function MODULES(pattern) {
  */
 function extractPatterns(patterns, type) {
   // Clone and apply the pattern environment.
-  const patternsList = patterns.map(function(pattern) {
+  const patternsList = patterns.map(function (pattern) {
-    return pattern[type].map(function(applyCondition) {
+    return pattern[type].map(function (applyCondition) {
       const thisPattern = cloneDeep(pattern);
 
       applyCondition(thisPattern);

package.json

@@ -57,7 +57,7 @@
     "lodash": "^4.17.13",
     "mergeiterator": "^1.2.5",
     "output-file-sync": "^2.0.0",
-    "prettier": "^1.19.1",
+    "prettier": "^2.0.5",
     "pump": "^3.0.0",
     "rimraf": "^2.6.3",
     "rollup": "1.27.9",

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

@@ -22,7 +22,7 @@ function outputFileSync(filePath: string, data: string | Buffer): void {
   fs.writeFileSync(filePath, data);
 }
 
-export default async function({
+export default async function ({
   cliOptions,
   babelOptions,
 }: CmdOptions): Promise<void> {
@@ -143,7 +143,7 @@ export default async function({
   let startTime = null;
 
   const logSuccess = debounce(
-    function() {
+    function () {
       if (startTime === null) {
         // This should never happen, but just in case it's better
         // to ignore the log message rather than making @babel/cli crash.
@@ -189,7 +189,7 @@ export default async function({
   if (cliOptions.watch) {
     const chokidar = util.requireChokidar();
 
-    filenames.forEach(function(filenameOrDir: string): void {
+    filenames.forEach(function (filenameOrDir: string): void {
       const watcher = chokidar.watch(filenameOrDir, {
         persistent: true,
         ignoreInitial: true,
@@ -203,8 +203,8 @@ export default async function({
       // when we are sure that all the files have been compiled.
       let processing = 0;
 
-      ["add", "change"].forEach(function(type: string): void {
+      ["add", "change"].forEach(function (type: string): void {
-        watcher.on(type, async function(filename: string) {
+        watcher.on(type, async function (filename: string) {
           processing++;
           if (startTime === null) startTime = process.hrtime();
 

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

@@ -16,7 +16,7 @@ type CompilationOutput = {
   map: Object,
 };
 
-export default async function({
+export default async function ({
   cliOptions,
   babelOptions,
 }: CmdOptions): Promise<void> {
@@ -41,7 +41,7 @@ export default async function({
         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({
@@ -111,13 +111,13 @@ export default async function({
 
       process.stdin.setEncoding("utf8");
 
-      process.stdin.on("readable", function() {
+      process.stdin.on("readable", function () {
         const chunk = process.stdin.read();
         // $FlowIgnore
         if (chunk !== null) code += chunk;
       });
 
-      process.stdin.on("end", function() {
+      process.stdin.on("end", function () {
         resolve(code);
       });
       process.stdin.on("error", reject);
@@ -144,7 +144,7 @@ export default async function({
   async function walk(filenames: Array<string>): Promise<void> {
     const _filenames = [];
 
-    filenames.forEach(function(filename) {
+    filenames.forEach(function (filename) {
       if (!fs.existsSync(filename)) return;
 
       const stat = fs.statSync(filename);
@@ -157,7 +157,7 @@ export default async function({
             cliOptions.includeDotfiles,
             cliOptions.extensions,
           )
-          .forEach(function(filename) {
+          .forEach(function (filename) {
             _filenames.push(path.join(dirname, filename));
           });
       } else {
@@ -166,7 +166,7 @@ export default async function({
     });
 
     const results = await Promise.all(
-      _filenames.map(async function(filename: string): Promise<Object> {
+      _filenames.map(async function (filename: string): Promise<Object> {
         let sourceFilename = filename;
         if (cliOptions.outFile) {
           sourceFilename = path.relative(
@@ -224,7 +224,7 @@ export default async function({
             pollInterval: 10,
           },
         })
-        .on("all", function(type: string, filename: string): void {
+        .on("all", function (type: string, filename: string): void {
           if (
             !util.isCompilableExtension(filename, cliOptions.extensions) &&
             !filenames.includes(filename)

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

@@ -189,7 +189,7 @@ export default function parseArgv(args: Array<string>): CmdOptions | null {
 
   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);
@@ -197,7 +197,7 @@ export default function parseArgv(args: Array<string>): CmdOptions | null {
 
   filenames = uniq(filenames);
 
-  filenames.forEach(function(filename) {
+  filenames.forEach(function (filename) {
     if (!fs.existsSync(filename)) {
       errors.push(filename + " does not exist");
     }
@@ -255,7 +255,7 @@ export default function parseArgv(args: Array<string>): CmdOptions | null {
 
   if (errors.length) {
     console.error("babel:");
-    errors.forEach(function(e) {
+    errors.forEach(function (e) {
       console.error("  " + e);
     });
     return null;

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

@@ -33,7 +33,7 @@ export function readdirForCompilable(
   includeDotfiles: boolean,
   altExts?: Array<string>,
 ): Array<string> {
-  return readdir(dirname, includeDotfiles, function(filename) {
+  return readdir(dirname, includeDotfiles, function (filename) {
     return isCompilableExtension(filename, altExts);
   });
 }
@@ -96,7 +96,7 @@ export function compile(
 
 export function deleteDir(path: string): void {
   if (fs.existsSync(path)) {
-    fs.readdirSync(path).forEach(function(file) {
+    fs.readdirSync(path).forEach(function (file) {
       const curPath = path + "/" + file;
       if (fs.lstatSync(curPath).isDirectory()) {
         // recurse
@@ -110,7 +110,7 @@ export function deleteDir(path: string): void {
   }
 }
 
-process.on("uncaughtException", function(err) {
+process.on("uncaughtException", function (err) {
   console.error(err);
   process.exitCode = 1;
 });

packages/babel-cli/test/index.js

@@ -10,11 +10,11 @@ const fs = require("fs");
 const fixtureLoc = path.join(__dirname, "fixtures");
 const tmpLoc = path.join(__dirname, "tmp");
 
-const fileFilter = function(x) {
+const fileFilter = function (x) {
   return x !== ".DS_Store";
 };
 
-const outputFileSync = function(filePath, data) {
+const outputFileSync = function (filePath, data) {
   makeDirSync(path.dirname(filePath));
   fs.writeFileSync(filePath, data);
 };
@@ -27,29 +27,29 @@ const pluginLocs = [
   path.join(__dirname, "/../../babel-plugin-transform-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.
   if (!fs.existsSync(".babelrc")) {
     outputFileSync(".babelrc", "{}");
   }
 
-  Object.keys(files).forEach(function(filename) {
+  Object.keys(files).forEach(function (filename) {
     const content = files[filename];
     outputFileSync(filename, content);
   });
 };
 
-const normalizeOutput = function(str, cwd) {
+const normalizeOutput = function (str, cwd) {
   let prev;
   do {
     prev = str;
@@ -59,7 +59,7 @@ const normalizeOutput = function(str, cwd) {
   return str.replace(/\(\d+ms\)/g, "(123ms)");
 };
 
-const assertTest = function(stdout, stderr, opts, cwd) {
+const assertTest = function (stdout, stderr, opts, cwd) {
   stdout = normalizeOutput(stdout, cwd);
   stderr = normalizeOutput(stderr, cwd);
 
@@ -94,7 +94,7 @@ const assertTest = function(stdout, stderr, opts, cwd) {
   if (opts.outFiles) {
     const actualFiles = readDir(tmpLoc, fileFilter);
 
-    Object.keys(actualFiles).forEach(function(filename) {
+    Object.keys(actualFiles).forEach(function (filename) {
       try {
         if (
           // saveInFiles always creates an empty .babelrc, so lets exclude for now
@@ -113,16 +113,16 @@ const assertTest = function(stdout, stderr, opts, cwd) {
       }
     });
 
-    Object.keys(opts.outFiles).forEach(function(filename) {
+    Object.keys(opts.outFiles).forEach(function (filename) {
       expect(actualFiles).toHaveProperty([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) {
     saveInFiles(opts.inFiles);
 
     let args = [binLoc];
@@ -138,15 +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 {
@@ -170,11 +170,11 @@ const buildTest = function(binName, testName, opts) {
   };
 };
 
-fs.readdirSync(fixtureLoc).forEach(function(binName) {
+fs.readdirSync(fixtureLoc).forEach(function (binName) {
   if (binName.startsWith(".")) return;
 
   const suiteLoc = path.join(fixtureLoc, binName);
-  describe("bin/" + binName, function() {
+  describe("bin/" + binName, function () {
     let cwd;
 
     beforeEach(() => {
@@ -195,7 +195,7 @@ fs.readdirSync(fixtureLoc).forEach(function(binName) {
       process.chdir(cwd);
     });
 
-    fs.readdirSync(suiteLoc).forEach(function(testName) {
+    fs.readdirSync(suiteLoc).forEach(function (testName) {
       if (testName.startsWith(".")) return;
 
       const testLoc = path.join(suiteLoc, testName);
@@ -229,7 +229,7 @@ fs.readdirSync(fixtureLoc).forEach(function(binName) {
         merge(opts, taskOpts);
       }
 
-      ["stdout", "stdin", "stderr"].forEach(function(key) {
+      ["stdout", "stdin", "stderr"].forEach(function (key) {
         const loc = path.join(testLoc, key + ".txt");
         opts[key + "Path"] = loc;
         if (fs.existsSync(loc)) {

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

@@ -175,7 +175,7 @@ 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,

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

@@ -2,8 +2,8 @@ import chalk from "chalk";
 import stripAnsi from "strip-ansi";
 import codeFrame, { codeFrameColumns } from "..";
 
-describe("@babel/code-frame", function() {
+describe("@babel/code-frame", function () {
-  test("basic usage", function() {
+  test("basic usage", function () {
     const rawLines = ["class Foo {", "  constructor()", "};"].join("\n");
     expect(codeFrame(rawLines, 2, 16)).toEqual(
       [
@@ -15,14 +15,14 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("optional column number", function() {
+  test("optional column number", function () {
     const rawLines = ["class Foo {", "  constructor()", "};"].join("\n");
     expect(codeFrame(rawLines, 2, null)).toEqual(
       ["  1 | class Foo {", "> 2 |   constructor()", "  3 | };"].join("\n"),
     );
   });
 
-  test("maximum context lines and padding", function() {
+  test("maximum context lines and padding", function () {
     const rawLines = [
       "/**",
       " * Sums two numbers.",
@@ -49,7 +49,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("no unnecessary padding due to one-off errors", function() {
+  test("no unnecessary padding due to one-off errors", function () {
     const rawLines = [
       "/**",
       " * Sums two numbers.",
@@ -76,7 +76,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("tabs", function() {
+  test("tabs", function () {
     const rawLines = [
       "\tclass Foo {",
       "\t  \t\t    constructor\t(\t)",
@@ -92,7 +92,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.highlightCode", function() {
+  test("opts.highlightCode", function () {
     const rawLines = "console.log('babel')";
     const result = codeFrame(rawLines, 1, 9, { highlightCode: true });
     const stripped = stripAnsi(result);
@@ -102,7 +102,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.highlightCode with multiple columns and lines", function() {
+  test("opts.highlightCode with multiple columns and lines", function () {
     // prettier-ignore
     const rawLines = [
       "function a(b, c) {", 
@@ -141,7 +141,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.linesAbove", function() {
+  test("opts.linesAbove", function () {
     const rawLines = [
       "/**",
       " * Sums two numbers.",
@@ -167,7 +167,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.linesBelow", function() {
+  test("opts.linesBelow", function () {
     const rawLines = [
       "/**",
       " * Sums two numbers.",
@@ -192,7 +192,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.linesAbove and opts.linesBelow", function() {
+  test("opts.linesAbove and opts.linesBelow", function () {
     const rawLines = [
       "/**",
       " * Sums two numbers.",
@@ -213,7 +213,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.linesAbove no lines above", function() {
+  test("opts.linesAbove no lines above", function () {
     const rawLines = [
       "class Foo {",
       "  constructor() {",
@@ -233,7 +233,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.linesBelow no lines below", function() {
+  test("opts.linesBelow no lines below", function () {
     const rawLines = [
       "class Foo {",
       "  constructor() {",
@@ -246,7 +246,7 @@ describe("@babel/code-frame", function() {
     ).toEqual(["  1 | class Foo {", "> 2 |   constructor() {"].join("\n"));
   });
 
-  test("opts.linesBelow single line", function() {
+  test("opts.linesBelow single line", function () {
     const rawLines = [
       "class Foo {",
       "  constructor() {",
@@ -263,7 +263,7 @@ describe("@babel/code-frame", function() {
     ).toEqual(["> 2 |   constructor() {"].join("\n"));
   });
 
-  test("opts.forceColor", function() {
+  test("opts.forceColor", function () {
     const marker = chalk.red.bold;
     const gutter = chalk.grey;
 
@@ -285,7 +285,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("basic usage, new API", function() {
+  test("basic usage, new API", function () {
     const rawLines = ["class Foo {", "  constructor()", "};"].join("\n");
     expect(
       codeFrameColumns(rawLines, { start: { line: 2, column: 16 } }),
@@ -299,7 +299,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("mark multiple columns", function() {
+  test("mark multiple columns", function () {
     const rawLines = ["class Foo {", "  constructor()", "};"].join("\n");
     expect(
       codeFrameColumns(rawLines, {
@@ -316,7 +316,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("mark multiple columns across lines", function() {
+  test("mark multiple columns across lines", function () {
     const rawLines = ["class Foo {", "  constructor() {", "  }", "};"].join(
       "\n",
     );
@@ -337,7 +337,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("mark multiple columns across multiple lines", function() {
+  test("mark multiple columns across multiple lines", function () {
     const rawLines = [
       "class Foo {",
       "  constructor() {",
@@ -364,7 +364,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("mark across multiple lines without columns", function() {
+  test("mark across multiple lines without columns", function () {
     const rawLines = [
       "class Foo {",
       "  constructor() {",
@@ -385,7 +385,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.message", function() {
+  test("opts.message", function () {
     const rawLines = ["class Foo {", "  constructor()", "};"].join("\n");
     expect(
       codeFrameColumns(
@@ -405,7 +405,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.message without column", function() {
+  test("opts.message without column", function () {
     const rawLines = ["class Foo {", "  constructor()", "};"].join("\n");
     expect(
       codeFrameColumns(
@@ -425,7 +425,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.message with multiple lines", function() {
+  test("opts.message with multiple lines", function () {
     const rawLines = [
       "class Foo {",
       "  constructor() {",
@@ -458,7 +458,7 @@ describe("@babel/code-frame", function() {
     );
   });
 
-  test("opts.message with multiple lines without columns", function() {
+  test("opts.message with multiple lines without columns", function () {
     const rawLines = [
       "class Foo {",
       "  constructor() {",

packages/babel-compat-data/scripts/utils-build-data.js

@@ -122,7 +122,7 @@ exports.generateData = (environments, features) => {
   });
 };
 
-exports.writeFile = function(data, dataPath, name) {
+exports.writeFile = function (data, dataPath, name) {
   const stringified = JSON.stringify(data, null, 2) + "\n";
   if (process.env.CHECK_COMPAT_DATA) {
     const currentData = fs.readFileSync(dataPath, "utf8");

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

@@ -330,7 +330,7 @@ class CacheConfigurator<SideChannel = void> {
 
   validator(): SideChannel => Handler<boolean> {
     const pairs = this._pairs;
-    return function*(data: SideChannel) {
+    return function* (data: SideChannel) {
       for (const [key, fn] of pairs) {
         if (key !== (yield* fn(data))) return false;
       }

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

@@ -429,7 +429,7 @@ function makeChainWalker<ArgT: { options: ValidatedOptions, dirname: string }>({
   ConfigContext,
   Set<ConfigFile> | void,
 ) => Handler<ConfigChain | null> {
-  return function*(input, context, files = new Set()) {
+  return function* (input, context, files = new Set()) {
     const { dirname } = input;
 
     const flattenedConfigs = [];

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

@@ -9,7 +9,7 @@ import nodeFs from "fs";
 export function makeStaticFileCache<T>(
   fn: (string, string) => T,
 ): Gensync<[string], T | null> {
-  return (makeStrongCache(function*(
+  return (makeStrongCache(function* (
     filepath: string,
     cache: CacheConfigurator<?void>,
   ): Handler<null | T> {

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

@@ -211,7 +211,7 @@ export default gensync<[any], ResolvedConfig | null>(function* loadFullConfig(
 /**
  * Load a generic plugin/preset from the given descriptor loaded from the config object.
  */
-const loadDescriptor = makeWeakCache(function*(
+const loadDescriptor = makeWeakCache(function* (
   { value, options, dirname, alias }: UnloadedDescriptor,
   cache: CacheConfigurator<SimpleContext>,
 ): Handler<LoadedDescriptor> {
@@ -277,7 +277,7 @@ function* loadPluginDescriptor(
   );
 }
 
-const instantiatePlugin = makeWeakCache(function*(
+const instantiatePlugin = makeWeakCache(function* (
   { value, options, dirname, alias }: LoadedDescriptor,
   cache: CacheConfigurator<SimpleContext>,
 ): Handler<Plugin> {
@@ -383,7 +383,7 @@ function chain(a, b) {
   const fns = [a, b].filter(Boolean);
   if (fns.length <= 1) return fns[0];
 
-  return function(...args) {
+  return function (...args) {
     for (const fn of fns) {
       fn.apply(this, args);
     }

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

@@ -15,7 +15,7 @@ import { loadPartialConfig as loadPartialConfigRunner } from "./partial";
 export { loadFullConfig as default };
 export type { PartialConfig } from "./partial";
 
-const loadOptionsRunner = gensync<[mixed], Object | null>(function*(opts) {
+const loadOptionsRunner = gensync<[mixed], Object | null>(function* (opts) {
   const config = yield* loadFullConfig(opts);
   // NOTE: We want to return "null" explicitly, while ?. alone returns undefined
   return config?.options ?? null;

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

@@ -135,30 +135,32 @@ export default function* loadPrivatePartialConfig(
   };
 }
 
-export const loadPartialConfig = gensync<[any], PartialConfig | null>(function*(
+export const loadPartialConfig = gensync<[any], PartialConfig | null>(
-  inputOpts: mixed,
+  function* (inputOpts: mixed): Handler<PartialConfig | null> {
-): Handler<PartialConfig | null> {
+    const result: ?PrivPartialConfig = yield* loadPrivatePartialConfig(
-  const result: ?PrivPartialConfig = yield* loadPrivatePartialConfig(inputOpts);
+      inputOpts,
-  if (!result) return null;
+    );
+    if (!result) return null;
 
-  const { options, babelrc, ignore, config } = result;
+    const { options, babelrc, ignore, config } = result;
 
-  (options.plugins || []).forEach(item => {
+    (options.plugins || []).forEach(item => {
-    if (item.value instanceof Plugin) {
+      if (item.value instanceof Plugin) {
-      throw new Error(
+        throw new Error(
-        "Passing cached plugin instances is not supported in " +
+          "Passing cached plugin instances is not supported in " +
-          "babel.loadPartialConfig()",
+            "babel.loadPartialConfig()",
-      );
+        );
-    }
+      }
-  });
+    });
 
-  return new PartialConfig(
+    return new PartialConfig(
-    options,
+      options,
-    babelrc ? babelrc.filepath : undefined,
+      babelrc ? babelrc.filepath : undefined,
-    ignore ? ignore.filepath : undefined,
+      ignore ? ignore.filepath : undefined,
-    config ? config.filepath : undefined,
+      config ? config.filepath : undefined,
-  );
+    );
-});
+  },
+);
 
 export type { PartialConfig };
 

packages/babel-core/src/gensync-utils/async.js

@@ -6,7 +6,7 @@ type MaybePromise<T> = T | Promise<T>;
 
 const id = x => x;
 
-const runGenerator = gensync(function*(item) {
+const runGenerator = gensync(function* (item) {
   return yield* item;
 });
 
@@ -76,10 +76,10 @@ export function forwardAsync<ActionArgs: mixed[], ActionReturn, Return>(
 export const onFirstPause = (gensync<[any, any], any>({
   name: "onFirstPause",
   arity: 2,
-  sync: function(item) {
+  sync: function (item) {
     return runGenerator.sync(item);
   },
-  errback: function(item, firstPause, cb) {
+  errback: function (item, firstPause, cb) {
     let completed = false;
 
     runGenerator.errback(item, (err, value) => {

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

@@ -132,7 +132,7 @@ function buildHelpers(body, namespace, whitelist) {
   };
 
   const refs = {};
-  helpers.list.forEach(function(name) {
+  helpers.list.forEach(function (name) {
     if (whitelist && whitelist.indexOf(name) < 0) return;
 
     const ref = (refs[name] = getHelperReference(name));
@@ -144,7 +144,7 @@ function buildHelpers(body, namespace, whitelist) {
   });
   return refs;
 }
-export default function(
+export default function (
   whitelist?: Array<string>,
   outputType: "global" | "module" | "umd" | "var" = "global",
 ) {

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

@@ -28,7 +28,7 @@ type TransformFromAst = {
 const transformFromAstRunner = gensync<
   [AstRoot, string, ?InputOptions],
   FileResult | null,
->(function*(ast, code, opts) {
+>(function* (ast, code, opts) {
   const config: ResolvedConfig | null = yield* loadConfig(opts);
   if (config === null) return null;
 

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

@@ -24,7 +24,7 @@ type TransformFile = {
 };
 
 const transformFileRunner = gensync<[string, ?InputOptions], FileResult | null>(
-  function*(filename, opts) {
+  function* (filename, opts) {
     const options = { ...opts, filename };
 
     const config: ResolvedConfig | null = yield* loadConfig(options);

packages/babel-core/src/transformation/block-hoist-plugin.js

@@ -51,7 +51,7 @@ const blockHoistPlugin = {
         }
         if (!hasChange) return;
 
-        node.body = sortBy(node.body, function(bodyNode) {
+        node.body = sortBy(node.body, function (bodyNode) {
           let priority = bodyNode?._blockHoist;
           if (priority == null) priority = 1;
           if (priority === true) priority = 2;

packages/babel-core/test/api.js

@@ -57,12 +57,12 @@ function transformFromAst(ast, code, opts) {
   });
 }
 
-describe("parser and generator options", function() {
+describe("parser and generator options", function () {
   const recast = {
-    parse: function(code, opts) {
+    parse: function (code, opts) {
       return opts.parser.parse(code);
     },
-    print: function(ast) {
+    print: function (ast) {
       return generator(ast);
     },
   };
@@ -81,7 +81,7 @@ describe("parser and generator options", function() {
     });
   }
 
-  it("options", function() {
+  it("options", function () {
     const string = "original;";
     expect(newTransform(string).ast).toEqual(
       transform(string, { ast: true }).ast,
@@ -89,7 +89,7 @@ describe("parser and generator options", function() {
     expect(newTransform(string).code).toBe(string);
   });
 
-  it("experimental syntax", function() {
+  it("experimental syntax", function () {
     const experimental = "var a: number = 1;";
 
     expect(newTransform(experimental).ast).toEqual(
@@ -126,7 +126,7 @@ describe("parser and generator options", function() {
     expect(newTransformWithPlugins(experimental).code).toBe(experimental);
   });
 
-  it("other options", function() {
+  it("other options", function () {
     const experimental = "if (true) {\n  import a from 'a';\n}";
 
     expect(newTransform(experimental).ast).not.toBe(
@@ -141,33 +141,33 @@ describe("parser and generator options", function() {
   });
 });
 
-describe("api", function() {
+describe("api", function () {
-  it("exposes the resolvePlugin method", function() {
+  it("exposes the resolvePlugin method", function () {
     expect(() => babel.resolvePlugin("nonexistent-plugin")).toThrow(
       /Cannot find module 'babel-plugin-nonexistent-plugin'/,
     );
   });
 
-  it("exposes the resolvePreset method", function() {
+  it("exposes the resolvePreset method", function () {
     expect(() => babel.resolvePreset("nonexistent-preset")).toThrow(
       /Cannot find module 'babel-preset-nonexistent-preset'/,
     );
   });
 
-  it("exposes types", function() {
+  it("exposes types", function () {
     expect(babel.types).toBeDefined();
   });
 
-  it("exposes the parser's token types", function() {
+  it("exposes the parser's token types", function () {
     expect(babel.tokTypes).toBeDefined();
   });
 
-  it("transformFile", function(done) {
+  it("transformFile", function (done) {
     const options = {
       babelrc: false,
     };
     Object.freeze(options);
-    transformFile(__dirname + "/fixtures/api/file.js", options, function(
+    transformFile(__dirname + "/fixtures/api/file.js", options, function (
       err,
       res,
     ) {
@@ -179,7 +179,7 @@ describe("api", function() {
     });
   });
 
-  it("transformFileSync", function() {
+  it("transformFileSync", function () {
     const options = {
       babelrc: false,
     };
@@ -190,15 +190,15 @@ describe("api", function() {
     expect(options).toEqual({ babelrc: false });
   });
 
-  it("transformFromAst should not mutate the AST", function() {
+  it("transformFromAst should not mutate the AST", function () {
     const program = "const identifier = 1";
     const node = parse(program);
     const { code } = transformFromAst(node, program, {
       plugins: [
-        function() {
+        function () {
           return {
             visitor: {
-              Identifier: function(path) {
+              Identifier: function (path) {
                 path.node.name = "replaced";
               },
             },
@@ -214,38 +214,38 @@ describe("api", function() {
     );
   });
 
-  it("options throw on falsy true", function() {
+  it("options throw on falsy true", function () {
-    return expect(function() {
+    return expect(function () {
       transform("", {
         plugins: [__dirname + "/../../babel-plugin-syntax-jsx", false],
       });
     }).toThrow(/.plugins\[1\] must be a string, object, function/);
   });
 
-  it("options merge backwards", function() {
+  it("options merge backwards", function () {
     return transformAsync("", {
       presets: [__dirname + "/../../babel-preset-env"],
       plugins: [__dirname + "/../../babel-plugin-syntax-jsx"],
-    }).then(function(result) {
+    }).then(function (result) {
       expect(result.options.plugins[0].manipulateOptions.toString()).toEqual(
         expect.stringContaining("jsx"),
       );
     });
   });
 
-  it("option wrapPluginVisitorMethod", function() {
+  it("option wrapPluginVisitorMethod", function () {
     let calledRaw = 0;
     let calledIntercept = 0;
 
     transform("function foo() { bar(foobar); }", {
-      wrapPluginVisitorMethod: function(pluginAlias, visitorType, callback) {
+      wrapPluginVisitorMethod: function (pluginAlias, visitorType, callback) {
         if (pluginAlias !== "foobar") {
           return callback;
         }
 
         expect(visitorType).toBe("enter");
 
-        return function() {
+        return function () {
           calledIntercept++;
           return callback.apply(this, arguments);
         };
@@ -255,7 +255,7 @@ describe("api", function() {
         new Plugin({
           name: "foobar",
           visitor: {
-            "Program|Identifier": function() {
+            "Program|Identifier": function () {
               calledRaw++;
             },
           },
@@ -267,7 +267,7 @@ describe("api", function() {
     expect(calledIntercept).toBe(4);
   });
 
-  it("pass per preset", function() {
+  it("pass per preset", function () {
     let aliasBaseType = null;
 
     function execTest(passPerPreset) {
@@ -276,12 +276,12 @@ describe("api", function() {
         passPerPreset: passPerPreset,
         presets: [
           // First preset with our plugin, "before"
-          function() {
+          function () {
             return {
               plugins: [
                 new Plugin({
                   visitor: {
-                    Function: function(path) {
+                    Function: function (path) {
                       const alias = path.scope
                         .getProgramParent()
                         .path.get("body")[0].node;
@@ -307,7 +307,7 @@ describe("api", function() {
           require(__dirname + "/../../babel-preset-env"),
 
           // Third preset for Flow.
-          function() {
+          function () {
             return {
               plugins: [
                 require(__dirname + "/../../babel-plugin-syntax-flow"),
@@ -339,7 +339,7 @@ describe("api", function() {
     expect(result.code).toBe("var x = function x(y) {\n  return y;\n};");
   });
 
-  it("complex plugin and preset ordering", function() {
+  it("complex plugin and preset ordering", function () {
     function pushPlugin(str) {
       return {
         visitor: {
@@ -414,7 +414,7 @@ describe("api", function() {
     );
   });
 
-  it("interpreter directive backward-compat", function() {
+  it("interpreter directive backward-compat", function () {
     function doTransform(code, preHandler) {
       return transform(code, {
         plugins: [
@@ -468,7 +468,7 @@ describe("api", function() {
     ).toBe(`#!env node3`);
   });
 
-  it("source map merging", function() {
+  it("source map merging", function () {
     const result = transform(
       [
         /* eslint-disable max-len */
@@ -515,52 +515,54 @@ describe("api", function() {
     });
   });
 
-  it("default source map filename", function() {
+  it("default source map filename", function () {
     return transformAsync("var a = 10;", {
       cwd: "/some/absolute",
       filename: "/some/absolute/file/path.js",
       sourceMaps: true,
-    }).then(function(result) {
+    }).then(function (result) {
       expect(result.map.sources).toEqual(["path.js"]);
     });
   });
 
-  it("code option false", function() {
+  it("code option false", function () {
-    return transformAsync("foo('bar');", { code: false }).then(function(
+    return transformAsync("foo('bar');", { code: false }).then(function (
       result,
     ) {
       expect(result.code).toBeFalsy();
     });
   });
 
-  it("ast option false", function() {
+  it("ast option false", function () {
-    return transformAsync("foo('bar');", { ast: false }).then(function(result) {
+    return transformAsync("foo('bar');", { ast: false }).then(function (
+      result,
+    ) {
       expect(result.ast).toBeFalsy();
     });
   });
 
-  it("ast option true", function() {
+  it("ast option true", function () {
-    return transformAsync("foo('bar');", { ast: true }).then(function(result) {
+    return transformAsync("foo('bar');", { ast: true }).then(function (result) {
       expect(result.ast).toBeTruthy();
     });
   });
 
-  it("ast option default", function() {
+  it("ast option default", function () {
-    return transformAsync("foo('bar');").then(function(result) {
+    return transformAsync("foo('bar');").then(function (result) {
       expect(result.ast).toBeFalsy();
     });
   });
 
-  it("auxiliaryComment option", function() {
+  it("auxiliaryComment option", function () {
     return transformAsync("class Foo {}", {
       auxiliaryCommentBefore: "before",
       auxiliaryCommentAfter: "after",
       plugins: [
-        function(babel) {
+        function (babel) {
           const t = babel.types;
           return {
             visitor: {
-              Program: function(path) {
+              Program: function (path) {
                 path.unshiftContainer(
                   "body",
                   t.expressionStatement(t.identifier("start")),
@@ -574,14 +576,14 @@ describe("api", function() {
           };
         },
       ],
-    }).then(function(result) {
+    }).then(function (result) {
       expect(result.code).toBe(
         "/*before*/\nstart;\n\n/*after*/\nclass Foo {}\n\n/*before*/\nend;\n\n/*after*/",
       );
     });
   });
 
-  it("ignore option", function() {
+  it("ignore option", function () {
     return Promise.all([
       transformAsync("", {
         ignore: ["/foo"],
@@ -620,7 +622,7 @@ describe("api", function() {
     ]);
   });
 
-  it("only option", function() {
+  it("only option", function () {
     return Promise.all([
       transformAsync("", {
         only: ["/foo"],
@@ -659,23 +661,23 @@ describe("api", function() {
     ]);
   });
 
-  describe("env option", function() {
+  describe("env option", function () {
     const oldBabelEnv = process.env.BABEL_ENV;
     const oldNodeEnv = process.env.NODE_ENV;
 
-    beforeEach(function() {
+    beforeEach(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;
     });
 
-    afterAll(function() {
+    afterAll(function () {
       process.env.BABEL_ENV = oldBabelEnv;
       process.env.NODE_ENV = oldNodeEnv;
     });
 
-    it("default", function() {
+    it("default", function () {
       const result = transform("foo;", {
         env: {
           development: { comments: false },
@@ -685,7 +687,7 @@ describe("api", function() {
       expect(result.options.comments).toBe(false);
     });
 
-    it("BABEL_ENV", function() {
+    it("BABEL_ENV", function () {
       process.env.BABEL_ENV = "foo";
       const result = transform("foo;", {
         env: {
@@ -695,7 +697,7 @@ describe("api", function() {
       expect(result.options.comments).toBe(false);
     });
 
-    it("NODE_ENV", function() {
+    it("NODE_ENV", function () {
       process.env.NODE_ENV = "foo";
       const result = transform("foo;", {
         env: {
@@ -706,59 +708,59 @@ describe("api", function() {
     });
   });
 
-  describe("buildExternalHelpers", function() {
+  describe("buildExternalHelpers", function () {
-    describe("smoke tests", function() {
+    describe("smoke tests", function () {
-      it("builds external helpers in global output type", function() {
+      it("builds external helpers in global output type", function () {
         babel.buildExternalHelpers(null, "global");
       });
 
-      it("builds external helpers in module output type", function() {
+      it("builds external helpers in module output type", function () {
         babel.buildExternalHelpers(null, "module");
       });
 
-      it("builds external helpers in umd output type", function() {
+      it("builds external helpers in umd output type", function () {
         babel.buildExternalHelpers(null, "umd");
       });
 
-      it("builds external helpers in var output type", function() {
+      it("builds external helpers in var output type", function () {
         babel.buildExternalHelpers(null, "var");
       });
     });
 
-    it("all", function() {
+    it("all", function () {
       const script = babel.buildExternalHelpers();
       expect(script).toEqual(expect.stringContaining("classCallCheck"));
       expect(script).toEqual(expect.stringContaining("inherits"));
     });
 
-    it("whitelist", function() {
+    it("whitelist", function () {
       const script = babel.buildExternalHelpers(["inherits"]);
       expect(script).not.toEqual(expect.stringContaining("classCallCheck"));
       expect(script).toEqual(expect.stringContaining("inherits"));
     });
 
-    it("empty whitelist", function() {
+    it("empty whitelist", function () {
       const script = babel.buildExternalHelpers([]);
       expect(script).not.toEqual(expect.stringContaining("classCallCheck"));
       expect(script).not.toEqual(expect.stringContaining("inherits"));
     });
 
-    it("underscored", function() {
+    it("underscored", function () {
       const script = babel.buildExternalHelpers(["typeof"]);
       expect(script).toEqual(expect.stringContaining("typeof"));
     });
   });
 
-  describe("handle parsing errors", function() {
+  describe("handle parsing errors", function () {
     const options = {
       babelrc: false,
     };
 
-    it("only syntax plugin available", function(done) {
+    it("only syntax plugin available", function (done) {
       transformFile(
         __dirname + "/fixtures/api/parsing-errors/only-syntax/file.js",
         options,
-        function(err) {
+        function (err) {
           expect(err.message).toMatch(
             "Support for the experimental syntax 'pipelineOperator' isn't currently enabled (1:3):",
           );
@@ -771,11 +773,11 @@ describe("api", function() {
       );
     });
 
-    it("both syntax and transform plugin available", function(done) {
+    it("both syntax and transform plugin available", function (done) {
       transformFile(
         __dirname + "/fixtures/api/parsing-errors/syntax-and-transform/file.js",
         options,
-        function(err) {
+        function (err) {
           expect(err.message).toMatch(
             "Support for the experimental syntax 'logicalAssignment' isn't currently enabled (1:3):",
           );
@@ -789,13 +791,13 @@ describe("api", function() {
     });
   });
 
-  describe("missing helpers", function() {
+  describe("missing helpers", function () {
-    it("should always throw", function() {
+    it("should always throw", function () {
       expect(() =>
         babel.transformSync(``, {
           configFile: false,
           plugins: [
-            function() {
+            function () {
               return {
                 visitor: {
                   Program(path) {

packages/babel-core/test/async.js

@@ -11,12 +11,12 @@ describe("asynchronicity", () => {
   const base = path.join(__dirname, "fixtures", "async");
   let cwd;
 
-  beforeEach(function() {
+  beforeEach(function () {
     cwd = process.cwd();
     process.chdir(base);
   });
 
-  afterEach(function() {
+  afterEach(function () {
     process.chdir(cwd);
   });
 

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

@@ -421,7 +421,7 @@ describe("caching API", () => {
 
     it("should throw if the cache is configured asynchronously", async () => {
       const fn = gensync(
-        makeStrongCache(function*(arg, cache) {
+        makeStrongCache(function* (arg, cache) {
           yield* wait(1000);
           cache.never();
           return { arg };
@@ -435,7 +435,7 @@ describe("caching API", () => {
 
     it("should allow asynchronous cache invalidation functions", async () => {
       const fn = gensync(
-        makeStrongCache(function*(arg, cache) {
+        makeStrongCache(function* (arg, cache) {
           yield* waitFor(
             cache.using(async () => {
               await wait.async(50);
@@ -453,7 +453,7 @@ describe("caching API", () => {
 
     it("should allow synchronous yield before cache configuration", async () => {
       const fn = gensync(
-        makeStrongCache(function*(arg, cache) {
+        makeStrongCache(function* (arg, cache) {
           yield* gensync({
             sync: () => 2,
             errback: cb => cb(null, 2),

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

@@ -16,12 +16,12 @@ const pfs =
         return function copyFile(source, target) {
           const rd = fs.createReadStream(source);
           const wr = fs.createWriteStream(target);
-          return new Promise(function(resolve, reject) {
+          return new Promise(function (resolve, reject) {
             rd.on("error", reject);
             wr.on("error", reject);
             wr.on("finish", resolve);
             rd.pipe(wr);
-          }).catch(function(error) {
+          }).catch(function (error) {
             rd.destroy();
             wr.end();
             throw error;
@@ -69,7 +69,7 @@ async function getTemp(name) {
   return { cwd, tmp, config };
 }
 
-describe("buildConfigChain", function() {
+describe("buildConfigChain", function () {
   describe("test", () => {
     describe("single", () => {
       it("should process matching string values", () => {
@@ -702,8 +702,8 @@ describe("buildConfigChain", function() {
     });
   });
 
-  describe("caching", function() {
+  describe("caching", function () {
-    describe("programmatic options", function() {
+    describe("programmatic options", function () {
       const plugins1 = [() => ({})];
       const plugins2 = [() => ({})];
 
@@ -807,7 +807,7 @@ describe("buildConfigChain", function() {
       });
     });
 
-    describe("config file options", function() {
+    describe("config file options", function () {
       function touch(filepath) {
         const s = fs.statSync(filepath);
         fs.utimesSync(

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

@@ -40,7 +40,7 @@ describe("@babel/core config loading", () => {
 
   describe("loadPartialConfig", () => {
     it("should preserve disabled plugins in the partial config", () => {
-      const plugin = function() {
+      const plugin = function () {
         return {};
       };
 
@@ -59,7 +59,7 @@ describe("@babel/core config loading", () => {
     });
 
     it("should preserve disabled presets in the partial config", () => {
-      const preset = function() {
+      const preset = function () {
         return {};
       };
 

packages/babel-core/test/evaluation.js

@@ -1,12 +1,12 @@
 import traverse from "@babel/traverse";
 import { parse } from "@babel/parser";
 
-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();
         expect(evaluate.confident).toEqual(!notConfident);
         expect(evaluate.value).toEqual(value);

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

@@ -234,9 +234,9 @@ describe("option-manager", () => {
     });
   });
 
-  describe("presets", function() {
+  describe("presets", function () {
     function presetTest(name) {
-      it(name, function() {
+      it(name, function () {
         const options = loadOptions({
           presets: [
             path.join(__dirname, "fixtures/option-manager/presets", name),
@@ -250,7 +250,7 @@ describe("option-manager", () => {
     }
 
     function presetThrowsTest(name, msg) {
-      it(name, function() {
+      it(name, function () {
         expect(() =>
           loadOptions({
             presets: [

packages/babel-core/test/parse.js

@@ -6,8 +6,8 @@ function fixture(...args) {
   return path.join(__dirname, "fixtures", "parse", ...args);
 }
 
-describe("parse", function() {
+describe("parse", function () {
-  it("should parse using configuration from .babelrc when a filename is provided", function() {
+  it("should parse using configuration from .babelrc when a filename is provided", function () {
     const input = fs.readFileSync(fixture("input.js"), "utf8");
     const output = require(fixture("output"));
 
@@ -18,7 +18,7 @@ describe("parse", function() {
     expect(JSON.parse(JSON.stringify(result))).toEqual(output);
   });
 
-  it("should parse using passed in configuration", function() {
+  it("should parse using passed in configuration", function () {
     const input = fs.readFileSync(fixture("input.js"), "utf8");
     const output = require(fixture("output.json"));
 

packages/babel-core/test/path.js

@@ -1,8 +1,8 @@
 import { transform } from "../lib/index";
 import Plugin from "../lib/config/plugin";
 
-describe("traversal path", function() {
+describe("traversal path", function () {
-  it("replaceWithSourceString", function() {
+  it("replaceWithSourceString", function () {
     const expectCode = "function foo() {}";
 
     const actualCode = transform(expectCode, {
@@ -10,7 +10,7 @@ describe("traversal path", function() {
       plugins: [
         new Plugin({
           visitor: {
-            FunctionDeclaration: function(path) {
+            FunctionDeclaration: function (path) {
               path.replaceWithSourceString("console.whatever()");
             },
           },
@@ -21,7 +21,7 @@ describe("traversal path", function() {
     expect(actualCode).toBe("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, {
@@ -29,7 +29,7 @@ describe("traversal path", function() {
       plugins: [
         new Plugin({
           visitor: {
-            ArrowFunctionExpression: function(path) {
+            ArrowFunctionExpression: function (path) {
               path.get("body").replaceWith({
                 type: "BlockStatement",
                 body: [
@@ -51,7 +51,7 @@ describe("traversal path", function() {
     expect(actualCode).toBe("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, {
@@ -59,7 +59,7 @@ describe("traversal path", function() {
       plugins: [
         new Plugin({
           visitor: {
-            ArrowFunctionExpression: function(path) {
+            ArrowFunctionExpression: function (path) {
               path.get("body").replaceWith({
                 type: "BooleanLiteral",
                 value: true,
@@ -73,7 +73,7 @@ describe("traversal path", function() {
     expect(actualCode).toBe("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, {
@@ -81,7 +81,7 @@ describe("traversal path", function() {
       plugins: [
         new Plugin({
           visitor: {
-            ForInStatement: function(path) {
+            ForInStatement: function (path) {
               path.get("left").replaceWith({
                 type: "VariableDeclaration",
                 kind: "var",
@@ -104,7 +104,7 @@ describe("traversal path", function() {
     expect(actualCode).toBe("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, {
@@ -112,7 +112,7 @@ describe("traversal path", function() {
       plugins: [
         new Plugin({
           visitor: {
-            ForInStatement: function(path) {
+            ForInStatement: function (path) {
               path.get("left").replaceWith({
                 type: "Identifier",
                 name: "KEY",
@@ -126,7 +126,7 @@ describe("traversal path", function() {
     expect(actualCode).toBe("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, {
@@ -134,7 +134,7 @@ describe("traversal path", function() {
       plugins: [
         new Plugin({
           visitor: {
-            ForStatement: function(path) {
+            ForStatement: function (path) {
               path.get("init").replaceWith({
                 type: "VariableDeclaration",
                 kind: "var",
@@ -157,7 +157,7 @@ describe("traversal path", function() {
     expect(actualCode).toBe("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, {
@@ -165,7 +165,7 @@ describe("traversal path", function() {
       plugins: [
         new Plugin({
           visitor: {
-            ForStatement: function(path) {
+            ForStatement: function (path) {
               path.get("init").replaceWith({
                 type: "Identifier",
                 name: "KEY",

packages/babel-core/test/resolution.js

@@ -1,20 +1,20 @@
 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");
   let cwd;
 
-  beforeEach(function() {
+  beforeEach(function () {
     cwd = process.cwd();
     process.chdir(base);
   });
 
-  afterEach(function() {
+  afterEach(function () {
     process.chdir(cwd);
   });
 
-  it("should find module: presets", function() {
+  it("should find module: presets", function () {
     process.chdir("module-paths");
 
     babel.transform("", {
@@ -24,7 +24,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find module: plugins", function() {
+  it("should find module: plugins", function () {
     process.chdir("module-paths");
 
     babel.transform("", {
@@ -34,7 +34,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find standard presets", function() {
+  it("should find standard presets", function () {
     process.chdir("standard-paths");
 
     babel.transform("", {
@@ -44,7 +44,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find standard plugins", function() {
+  it("should find standard plugins", function () {
     process.chdir("standard-paths");
 
     babel.transform("", {
@@ -54,7 +54,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find standard presets with an existing prefix", function() {
+  it("should find standard presets with an existing prefix", function () {
     process.chdir("standard-paths");
 
     babel.transform("", {
@@ -64,7 +64,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find standard plugins with an existing prefix", function() {
+  it("should find standard plugins with an existing prefix", function () {
     process.chdir("standard-paths");
 
     babel.transform("", {
@@ -74,7 +74,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @babel scoped presets", function() {
+  it("should find @babel scoped presets", function () {
     process.chdir("babel-org-paths");
 
     babel.transform("", {
@@ -84,7 +84,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @babel scoped plugins", function() {
+  it("should find @babel scoped plugins", function () {
     process.chdir("babel-org-paths");
 
     babel.transform("", {
@@ -94,7 +94,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @babel scoped presets with an existing prefix", function() {
+  it("should find @babel scoped presets with an existing prefix", function () {
     process.chdir("babel-org-paths");
 
     babel.transform("", {
@@ -104,7 +104,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @babel scoped plugins", function() {
+  it("should find @babel scoped plugins", function () {
     process.chdir("babel-org-paths");
 
     babel.transform("", {
@@ -114,7 +114,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo scoped presets", function() {
+  it("should find @foo scoped presets", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -124,7 +124,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo scoped plugins", function() {
+  it("should find @foo scoped plugins", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -134,7 +134,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo scoped presets with an inner babel-preset", function() {
+  it("should find @foo scoped presets with an inner babel-preset", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -144,7 +144,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo scoped plugins with an inner babel-plugin", function() {
+  it("should find @foo scoped plugins with an inner babel-plugin", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -154,7 +154,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo scoped presets with an babel-preset suffix", function() {
+  it("should find @foo scoped presets with an babel-preset suffix", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -164,7 +164,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo scoped plugins with an babel-plugin suffix", function() {
+  it("should find @foo scoped plugins with an babel-plugin suffix", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -174,7 +174,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo scoped presets with an existing prefix", function() {
+  it("should find @foo scoped presets with an existing prefix", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -184,7 +184,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo scoped plugins with an existing prefix", function() {
+  it("should find @foo scoped plugins with an existing prefix", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -194,7 +194,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo/babel-plugin when specified", function() {
+  it("should find @foo/babel-plugin when specified", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -204,7 +204,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo/babel-preset when specified", function() {
+  it("should find @foo/babel-preset when specified", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -214,7 +214,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo/babel-plugin/index when specified", function() {
+  it("should find @foo/babel-plugin/index when specified", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -224,7 +224,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo/babel-preset/index when specified", function() {
+  it("should find @foo/babel-preset/index when specified", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -234,7 +234,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo/babel-plugin when just scope given", function() {
+  it("should find @foo/babel-plugin when just scope given", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -244,7 +244,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo/babel-preset when just scope given", function() {
+  it("should find @foo/babel-preset when just scope given", function () {
     process.chdir("foo-org-paths");
 
     babel.transform("", {
@@ -254,7 +254,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find relative path presets", function() {
+  it("should find relative path presets", function () {
     process.chdir("relative-paths");
 
     babel.transform("", {
@@ -264,7 +264,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find relative path plugins", function() {
+  it("should find relative path plugins", function () {
     process.chdir("relative-paths");
 
     babel.transform("", {
@@ -274,7 +274,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find module file presets", function() {
+  it("should find module file presets", function () {
     process.chdir("nested-module-paths");
 
     babel.transform("", {
@@ -284,7 +284,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find module file plugins", function() {
+  it("should find module file plugins", function () {
     process.chdir("nested-module-paths");
 
     babel.transform("", {
@@ -294,7 +294,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo scoped module file presets", function() {
+  it("should find @foo scoped module file presets", function () {
     process.chdir("scoped-nested-module-paths");
 
     babel.transform("", {
@@ -304,7 +304,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @foo scoped module file plugins", function() {
+  it("should find @foo scoped module file plugins", function () {
     process.chdir("scoped-nested-module-paths");
 
     babel.transform("", {
@@ -314,7 +314,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @babel scoped module file presets", function() {
+  it("should find @babel scoped module file presets", function () {
     process.chdir("babel-scoped-nested-module-paths");
 
     babel.transform("", {
@@ -324,7 +324,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should find @babel scoped module file plugins", function() {
+  it("should find @babel scoped module file plugins", function () {
     process.chdir("babel-scoped-nested-module-paths");
 
     babel.transform("", {
@@ -334,7 +334,7 @@ describe("addon resolution", function() {
     });
   });
 
-  it("should throw about module: usage for presets", function() {
+  it("should throw about module: usage for presets", function () {
     process.chdir("throw-module-paths");
 
     expect(() => {
@@ -348,7 +348,7 @@ describe("addon resolution", function() {
     );
   });
 
-  it("should throw about module: usage for plugins", function() {
+  it("should throw about module: usage for plugins", function () {
     process.chdir("throw-module-paths");
 
     expect(() => {
@@ -362,7 +362,7 @@ describe("addon resolution", function() {
     );
   });
 
-  it("should throw about @babel usage for presets", function() {
+  it("should throw about @babel usage for presets", function () {
     process.chdir("throw-babel-paths");
 
     expect(() => {
@@ -376,7 +376,7 @@ describe("addon resolution", function() {
     );
   });
 
-  it("should throw about @babel usage for plugins", function() {
+  it("should throw about @babel usage for plugins", function () {
     process.chdir("throw-babel-paths");
 
     expect(() => {
@@ -390,7 +390,7 @@ describe("addon resolution", function() {
     );
   });
 
-  it("should throw about passing a preset as a plugin", function() {
+  it("should throw about passing a preset as a plugin", function () {
     process.chdir("throw-opposite-paths");
 
     expect(() => {
@@ -404,7 +404,7 @@ describe("addon resolution", function() {
     );
   });
 
-  it("should throw about passing a plugin as a preset", function() {
+  it("should throw about passing a plugin as a preset", function () {
     process.chdir("throw-opposite-paths");
 
     expect(() => {
@@ -418,7 +418,7 @@ describe("addon resolution", function() {
     );
   });
 
-  it("should throw about missing presets", function() {
+  it("should throw about missing presets", function () {
     process.chdir("throw-missing-paths");
 
     expect(() => {
@@ -430,7 +430,7 @@ describe("addon resolution", function() {
     }).toThrow(/Cannot find module 'babel-preset-foo'/);
   });
 
-  it("should throw about missing plugins", function() {
+  it("should throw about missing plugins", function () {
     process.chdir("throw-missing-paths");
 
     expect(() => {

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

@@ -154,7 +154,7 @@ export function Import() {
 }
 
 function buildYieldAwait(keyword: string) {
-  return function(node: Object) {
+  return function (node: Object) {
     this.word(keyword);
 
     if (node.delegate) {

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

@@ -81,8 +81,8 @@ export function WhileStatement(node: Object) {
   this.printBlock(node);
 }
 
-const buildForXStatement = function(op) {
+const buildForXStatement = function (op) {
-  return function(node: Object) {
+  return function (node: Object) {
     this.word("for");
     this.space();
     if (op === "of" && node.await) {
@@ -117,7 +117,7 @@ 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];

packages/babel-generator/src/index.js

@@ -108,7 +108,7 @@ 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

@@ -8,7 +8,7 @@ function expandAliases(obj) {
   function add(type, func) {
     const fn = newObj[type];
     newObj[type] = fn
-      ? function(node, parent, stack) {
+      ? function (node, parent, stack) {
           const result = fn(node, parent, stack);
 
           return result == null ? func(node, parent, stack) : result;

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

@@ -181,7 +181,7 @@ export const nodes = {
  * Test if Property needs whitespace.
  */
 
-nodes.ObjectProperty = nodes.ObjectTypeProperty = nodes.ObjectMethod = function(
+nodes.ObjectProperty = nodes.ObjectTypeProperty = nodes.ObjectMethod = function (
   node: Object,
   parent,
 ): ?WhitespaceObject {
@@ -192,7 +192,7 @@ nodes.ObjectProperty = nodes.ObjectTypeProperty = nodes.ObjectMethod = function(
   }
 };
 
-nodes.ObjectTypeCallProperty = function(
+nodes.ObjectTypeCallProperty = function (
   node: Object,
   parent,
 ): ?WhitespaceObject {
@@ -203,7 +203,7 @@ nodes.ObjectTypeCallProperty = function(
   }
 };
 
-nodes.ObjectTypeIndexer = function(node: Object, parent): ?WhitespaceObject {
+nodes.ObjectTypeIndexer = function (node: Object, parent): ?WhitespaceObject {
   if (
     parent.indexers[0] === node &&
     !parent.properties?.length &&
@@ -215,7 +215,7 @@ nodes.ObjectTypeIndexer = function(node: Object, parent): ?WhitespaceObject {
   }
 };
 
-nodes.ObjectTypeInternalSlot = function(
+nodes.ObjectTypeInternalSlot = function (
   node: Object,
   parent,
 ): ?WhitespaceObject {
@@ -272,12 +272,12 @@ 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) {
+  [type].concat(t.FLIPPED_ALIAS_KEYS[type] || []).forEach(function (type) {
-    nodes[type] = function() {
+    nodes[type] = function () {
       return amounts;
     };
   });

packages/babel-generator/test/index.js

@@ -6,24 +6,24 @@ import fs from "fs";
 import path from "path";
 import fixtures from "@babel/helper-fixtures";
 
-describe("generation", function() {
+describe("generation", function () {
-  it("completeness", function() {
+  it("completeness", function () {
-    Object.keys(t.VISITOR_KEYS).forEach(function(type) {
+    Object.keys(t.VISITOR_KEYS).forEach(function (type) {
       expect(Printer.prototype[type]).toBeTruthy();
     });
 
-    Object.keys(Printer.prototype).forEach(function(type) {
+    Object.keys(Printer.prototype).forEach(function (type) {
       if (!/[A-Z]/.test(type[0])) return;
       expect(t.VISITOR_KEYS[type]).toBeTruthy();
     });
   });
 
-  it("multiple sources", function() {
+  it("multiple sources", function () {
     const sources = {
       "a.js": "function hi (msg) { console.log(msg); }\n",
       "b.js": "hi('hello');\n",
     };
-    const parsed = Object.keys(sources).reduce(function(_parsed, filename) {
+    const parsed = Object.keys(sources).reduce(function (_parsed, filename) {
       _parsed[filename] = parse(sources[filename], {
         sourceFilename: filename,
       });
@@ -185,7 +185,7 @@ describe("generation", function() {
     );
   });
 
-  it("identifierName", function() {
+  it("identifierName", function () {
     const code = "function foo() { bar; }\n";
 
     const ast = parse(code, { filename: "inline" }).program;
@@ -277,7 +277,7 @@ describe("generation", function() {
     expect(generated.code).toBe("function foo2() {\n  bar2;\n}");
   });
 
-  it("lazy source map generation", function() {
+  it("lazy source map generation", function () {
     const code = "function hi (msg) { console.log(msg); }\n";
 
     const ast = parse(code, { filename: "a.js" }).program;
@@ -306,8 +306,8 @@ describe("generation", function() {
   });
 });
 
-describe("programmatic generation", function() {
+describe("programmatic generation", function () {
-  it("should add parenthesis when NullishCoalescing is used along with ||", function() {
+  it("should add parenthesis when NullishCoalescing is used along with ||", function () {
     // https://github.com/babel/babel/issues/10260
     const nullishCoalesc = t.logicalExpression(
       "??",
@@ -318,7 +318,7 @@ describe("programmatic generation", function() {
     expect(output).toBe(`(a || b) ?? c`);
   });
 
-  it("should add parenthesis when NullishCoalesing is used with &&", function() {
+  it("should add parenthesis when NullishCoalesing is used with &&", function () {
     const nullishCoalesc = t.logicalExpression(
       "??",
       t.identifier("a"),
@@ -332,7 +332,7 @@ describe("programmatic generation", function() {
     expect(output).toBe(`a ?? (b && c && d)`);
   });
 
-  it("numeric member expression", function() {
+  it("numeric member expression", function () {
     // Should not generate `0.foo`
     const mem = t.memberExpression(
       t.numericLiteral(60702),
@@ -341,7 +341,7 @@ describe("programmatic generation", function() {
     new Function(generate(mem).code);
   });
 
-  it("nested if statements needs block", function() {
+  it("nested if statements needs block", function () {
     const ifStatement = t.ifStatement(
       t.stringLiteral("top cond"),
       t.whileStatement(
@@ -358,7 +358,7 @@ describe("programmatic generation", function() {
     expect(ast.program.body[0].consequent.type).toBe("BlockStatement");
   });
 
-  it("prints directives in block with empty body", function() {
+  it("prints directives in block with empty body", function () {
     const blockStatement = t.blockStatement(
       [],
       [t.directive(t.directiveLiteral("use strict"))],
@@ -370,7 +370,7 @@ describe("programmatic generation", function() {
 }`);
   });
 
-  it("flow object indentation", function() {
+  it("flow object indentation", function () {
     const objectStatement = t.objectTypeAnnotation(
       [t.objectTypeProperty(t.identifier("bar"), t.stringTypeAnnotation())],
       null,
@@ -384,7 +384,7 @@ describe("programmatic generation", function() {
 }`);
   });
 
-  it("flow object exact", function() {
+  it("flow object exact", function () {
     const objectStatement = t.objectTypeAnnotation(
       [t.objectTypeProperty(t.identifier("bar"), t.stringTypeAnnotation())],
       null,
@@ -399,7 +399,7 @@ describe("programmatic generation", function() {
 |}`);
   });
 
-  it("flow object indentation with empty leading ObjectTypeProperty", function() {
+  it("flow object indentation with empty leading ObjectTypeProperty", function () {
     const objectStatement = t.objectTypeAnnotation(
       [],
       [
@@ -419,8 +419,8 @@ describe("programmatic generation", function() {
 }`);
   });
 
-  describe("directives", function() {
+  describe("directives", function () {
-    it("preserves escapes", function() {
+    it("preserves escapes", function () {
       const directive = t.directive(
         t.directiveLiteral(String.raw`us\x65 strict`),
       );
@@ -429,7 +429,7 @@ describe("programmatic generation", function() {
       expect(output).toBe(String.raw`"us\x65 strict";`);
     });
 
-    it("preserves escapes in minified output", function() {
+    it("preserves escapes in minified output", function () {
       // https://github.com/babel/babel/issues/4767
 
       const directive = t.directive(t.directiveLiteral(String.raw`foo\n\t\r`));
@@ -438,21 +438,21 @@ describe("programmatic generation", function() {
       expect(output).toBe(String.raw`"foo\n\t\r";`);
     });
 
-    it("unescaped single quote", function() {
+    it("unescaped single quote", function () {
       const directive = t.directive(t.directiveLiteral(String.raw`'\'\"`));
       const output = generate(directive).code;
 
       expect(output).toBe(String.raw`"'\'\"";`);
     });
 
-    it("unescaped double quote", function() {
+    it("unescaped double quote", function () {
       const directive = t.directive(t.directiveLiteral(String.raw`"\'\"`));
       const output = generate(directive).code;
 
       expect(output).toBe(String.raw`'"\'\"';`);
     });
 
-    it("unescaped single and double quotes together throw", function() {
+    it("unescaped single and double quotes together throw", function () {
       const directive = t.directive(t.directiveLiteral(String.raw`'"`));
 
       expect(() => {
@@ -461,7 +461,7 @@ describe("programmatic generation", function() {
     });
   });
 
-  describe("typescript generate parentheses if necessary", function() {
+  describe("typescript generate parentheses if necessary", function () {
     it("wraps around union for array", () => {
       const typeStatement = t.TSArrayType(
         t.TSUnionType([
@@ -496,8 +496,8 @@ describe("programmatic generation", function() {
   });
 });
 
-describe("CodeGenerator", function() {
+describe("CodeGenerator", function () {
-  it("generate", function() {
+  it("generate", function () {
     const codeGen = new CodeGenerator(t.numericLiteral(123));
     const code = codeGen.generate().code;
     expect(parse(code).program.body[0].expression.value).toBe(123);
@@ -506,15 +506,15 @@ describe("CodeGenerator", function() {
 
 const suites = fixtures(`${__dirname}/fixtures`);
 
-suites.forEach(function(testSuite) {
+suites.forEach(function (testSuite) {
-  describe("generation/" + testSuite.title, function() {
+  describe("generation/" + testSuite.title, function () {
-    testSuite.tests.forEach(function(task) {
+    testSuite.tests.forEach(function (task) {
       const testFn = task.disabled ? it.skip : it;
 
       testFn(
         task.title,
 
-        function() {
+        function () {
           const expected = task.expect;
           const actual = task.actual;
           const actualCode = actual.code;

packages/babel-helper-builder-binary-assignment-operator-visitor/src/index.js

@@ -1,7 +1,7 @@
 import explode from "@babel/helper-explode-assignable-expression";
 import * as t from "@babel/types";
 
-export default function(opts: { build: Function, operator: string }): Object {
+export default function (opts: { build: Function, operator: string }): Object {
   const { build, operator } = opts;
 
   return {

packages/babel-helper-builder-react-jsx/src/index.js

@@ -9,10 +9,10 @@ type ElementState = {
   pure: boolean, // true if the element can be marked with a #__PURE__ annotation
 };
 
-export default function(opts) {
+export default function (opts) {
   const visitor = {};
 
-  visitor.JSXNamespacedName = function(path) {
+  visitor.JSXNamespacedName = function (path) {
     if (opts.throwIfNamespace) {
       throw path.buildCodeFrameError(
         `Namespace tags are not supported by default. React's JSX doesn't support namespace tags. \
@@ -21,7 +21,7 @@ You can set \`throwIfNamespace: false\` to bypass this warning.`,
     }
   };
 
-  visitor.JSXSpreadChild = function(path) {
+  visitor.JSXSpreadChild = function (path) {
     throw path.buildCodeFrameError(
       "Spread children are not supported in React.",
     );

packages/babel-helper-call-delegate/src/index.js

@@ -18,7 +18,7 @@ const visitor = {
   },
 };
 
-export default function(
+export default function (
   path: NodePath,
   scope = path.scope,
   shouldHoistVariables = true,

packages/babel-helper-define-map/src/index.js

@@ -124,13 +124,13 @@ export function toComputedObjectFromClass(obj: Object): Object {
 export function toClassObject(mutatorMap: Object): Object {
   const objExpr = t.objectExpression([]);
 
-  Object.keys(mutatorMap).forEach(function(mutatorMapKey) {
+  Object.keys(mutatorMap).forEach(function (mutatorMapKey) {
     const map = mutatorMap[mutatorMapKey];
     const mapNode = t.objectExpression([]);
 
     const propNode = t.objectProperty(map._key, mapNode, map._computed);
 
-    Object.keys(map).forEach(function(key) {
+    Object.keys(map).forEach(function (key) {
       const node = map[key];
       if (key[0] === "_") return;
 
@@ -148,7 +148,7 @@ export function toClassObject(mutatorMap: Object): Object {
 }
 
 export function toDefineObject(mutatorMap: Object): Object {
-  Object.keys(mutatorMap).forEach(function(key) {
+  Object.keys(mutatorMap).forEach(function (key) {
     const map = mutatorMap[key];
     if (map.value) map.writable = t.booleanLiteral(true);
     map.configurable = t.booleanLiteral(true);

packages/babel-helper-explode-assignable-expression/src/index.js

@@ -48,7 +48,7 @@ function getPropRef(node, nodes, file, scope) {
   return temp;
 }
 
-export default function(
+export default function (
   node: Object,
   nodes: Array<Object>,
   file,

packages/babel-helper-explode-class/src/index.js

@@ -2,7 +2,7 @@ import bindifyDecorators from "@babel/helper-bindify-decorators";
 import type { NodePath } from "@babel/traverse";
 import * as t from "@babel/types";
 
-export default function(classPath) {
+export default function (classPath) {
   classPath.assertClass();
 
   const memoisedExpressions = [];

packages/babel-helper-function-name/src/index.js

@@ -150,7 +150,7 @@ function visit(node, name, scope) {
  * @param {NodePath} param0
  * @param {Boolean} localBinding whether a name could shadow a self-reference (e.g. converting arrow function)
  */
-export default function({ node, parent, scope, id }, localBinding = false) {
+export default function ({ node, parent, scope, id }, localBinding = false) {
   // has an `id` so we don't need to infer one
   if (node.id) return;
 

packages/babel-helper-get-function-arity/src/index.js

@@ -1,6 +1,6 @@
 import * as t from "@babel/types";
 
-export default function(node): number {
+export default function (node): number {
   const params: Array<Object> = node.params;
   for (let i = 0; i < params.length; i++) {
     const param = params[i];

packages/babel-helper-hoist-variables/src/index.js

@@ -42,6 +42,6 @@ const visitor = {
   },
 };
 
-export default function(path, emit: Function, kind: "var" | "let" = "var") {
+export default function (path, emit: Function, kind: "var" | "let" = "var") {
   path.traverse(visitor, { kind, emit });
 }

packages/babel-helper-module-imports/src/import-injector.js

@@ -294,10 +294,7 @@ export default class ImportInjector {
             builder.var(importedSource).read(importName);
           }
         } else if (isDefault) {
-          builder
+          builder.var(name).defaultInterop().prop(importName);
-            .var(name)
-            .defaultInterop()
-            .prop(importName);
         } else if (isNamed) {
           builder.var(name).prop(importName);
         }

packages/babel-helper-module-imports/test/index.js

@@ -15,7 +15,7 @@ function test(sourceType, opts, initializer, expectedCode) {
     filename: "example" + (sourceType === "module" ? ".mjs" : ".js"),
     babelrc: false,
     plugins: [
-      function({ types: t }) {
+      function ({ types: t }) {
         return {
           pre(file) {
             file.set("helperGenerator", name =>

packages/babel-helper-optimise-call-expression/src/index.js

@@ -1,6 +1,6 @@
 import * as t from "@babel/types";
 
-export default function(callee, thisNode, args, optional) {
+export default function (callee, thisNode, args, optional) {
   if (
     args.length === 1 &&
     t.isSpreadElement(args[0]) &&

packages/babel-helper-plugin-test-runner/src/index.js

@@ -1,7 +1,7 @@
 import testRunner from "@babel/helper-transform-fixture-test-runner";
 import path from "path";
 
-export default function(loc) {
+export default function (loc) {
   const name = path.basename(path.dirname(loc));
   testRunner(loc + "/fixtures", name);
 }

packages/babel-helper-remap-async-to-generator/src/index.js

@@ -28,7 +28,7 @@ const awaitVisitor = {
   },
 };
 
-export default function(
+export default function (
   path: NodePath,
   helpers: { wrapAsync: Object, wrapAwait: Object },
 ) {

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

@@ -107,7 +107,7 @@ export function runCodeInTestContext(code: string, opts: { filename: string }) {
 }
 
 function wrapPackagesArray(type, names, optionsDir) {
-  return (names || []).map(function(val) {
+  return (names || []).map(function (val) {
     if (typeof val === "string") val = [val];
 
     // relative path (outside of monorepo)
@@ -164,7 +164,7 @@ function run(task) {
       "preset",
       newOpts.presets,
       optionsDir,
-    ).map(function(val) {
+    ).map(function (val) {
       if (val.length > 3) {
         throw new Error(
           "Unexpected extra options " +
@@ -269,7 +269,7 @@ function run(task) {
   if (task.sourceMappings) {
     const consumer = new sourceMap.SourceMapConsumer(result.map);
 
-    task.sourceMappings.forEach(function(mapping) {
+    task.sourceMappings.forEach(function (mapping) {
       const actual = mapping.original;
 
       const expected = consumer.originalPositionFor(mapping.generated);
@@ -342,7 +342,7 @@ const toEqualFile = () => ({
   },
 });
 
-export default function(
+export default function (
   fixturesLoc: string,
   name: string,
   suiteOpts = {},
@@ -354,7 +354,7 @@ export default function(
   for (const testSuite of suites) {
     if (includes(suiteOpts.ignoreSuites, testSuite.title)) continue;
 
-    describe(name + "/" + testSuite.title, function() {
+    describe(name + "/" + testSuite.title, function () {
       jest.addMatchers({
         toEqualFile,
       });
@@ -372,7 +372,7 @@ export default function(
         testFn(
           task.title,
 
-          function() {
+          function () {
             function runTask() {
               run(task);
             }
@@ -391,7 +391,7 @@ export default function(
               // the options object with useless options
               delete task.options.throws;
 
-              assert.throws(runTask, function(err) {
+              assert.throws(runTask, function (err) {
                 return throwMsg === true || err.message.indexOf(throwMsg) >= 0;
               });
             } else {

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

@@ -1,7 +1,7 @@
 import { runCodeInTestContext } from "..";
 
-describe("helper-transform-fixture-test-runner", function() {
+describe("helper-transform-fixture-test-runner", function () {
-  it("should not execute code in Node's global context", function() {
+  it("should not execute code in Node's global context", function () {
     try {
       global.foo = "outer";
       runCodeInTestContext(

packages/babel-helper-validator-identifier/scripts/generate-identifier-regex.js

@@ -6,14 +6,14 @@ const version = "13.0.0";
 
 const start = require("unicode-" +
   version +
-  "/Binary_Property/ID_Start/code-points.js").filter(function(ch) {
+  "/Binary_Property/ID_Start/code-points.js").filter(function (ch) {
   return ch > 0x7f;
 });
 let last = -1;
 const cont = [0x200c, 0x200d].concat(
   require("unicode-" +
     version +
-    "/Binary_Property/ID_Continue/code-points.js").filter(function(ch) {
+    "/Binary_Property/ID_Continue/code-points.js").filter(function (ch) {
     return ch > 0x7f && search(start, ch, last + 1) == -1;
   })
 );

packages/babel-helper-validator-identifier/test/identifier.spec.js

@@ -1,22 +1,22 @@
 import { isIdentifierName } from "..";
 
-describe("isIdentifierName", function() {
+describe("isIdentifierName", function () {
-  it("returns false if provided string is empty", function() {
+  it("returns false if provided string is empty", function () {
     expect(isIdentifierName("")).toBe(false);
   });
   it.each(["hello", "$", "ゆゆ式", "$20", "hello20", "_", "if"])(
     "returns true if provided string %p is an IdentifierName",
-    function(word) {
+    function (word) {
       expect(isIdentifierName(word)).toBe(true);
     },
   );
   it.each(["+hello", "0$", "-ゆゆ式", "#_", "_#"])(
     "returns false if provided string %p is not an IdentifierName",
-    function(word) {
+    function (word) {
       expect(isIdentifierName(word)).toBe(false);
     },
   );
-  it("supports astral symbols", function() {
+  it("supports astral symbols", function () {
     expect(isIdentifierName("x\uDB40\uDDD5")).toBe(true);
   });
 });

packages/babel-highlight/src/index.js

@@ -77,7 +77,7 @@ function getTokenType(match) {
  * Highlight `text` using the token definitions in `defs`.
  */
 function highlightTokens(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) {

packages/babel-highlight/test/index.js

@@ -2,24 +2,24 @@ import chalk from "chalk";
 import stripAnsi from "strip-ansi";
 import highlight, { shouldHighlight, getChalk } from "..";
 
-describe("@babel/highlight", function() {
+describe("@babel/highlight", function () {
   function stubColorSupport(supported) {
     let originalSupportsColor;
-    beforeEach(function() {
+    beforeEach(function () {
       originalSupportsColor = chalk.supportsColor;
       chalk.supportsColor = supported;
     });
 
-    afterEach(function() {
+    afterEach(function () {
       chalk.supportsColor = originalSupportsColor;
     });
   }
 
-  describe("highlight", function() {
+  describe("highlight", function () {
-    describe("when colors are supported", function() {
+    describe("when colors are supported", function () {
       stubColorSupport(true);
 
-      it("highlights code", function() {
+      it("highlights code", function () {
         const code = "console.log('hi')";
         const result = highlight(code);
         const stripped = stripAnsi(result);
@@ -28,10 +28,10 @@ describe("@babel/highlight", function() {
       });
     });
 
-    describe("when colors are not supported", function() {
+    describe("when colors are not supported", function () {
       stubColorSupport(false);
 
-      it("does not attempt to highlight code", function() {
+      it("does not attempt to highlight code", function () {
         const code = "console.log('hi')";
         const result = highlight(code);
         const stripped = stripAnsi(result);
@@ -39,8 +39,8 @@ describe("@babel/highlight", function() {
         expect(result).toBe(code);
       });
 
-      describe("and the forceColor option is passed", function() {
+      describe("and the forceColor option is passed", function () {
-        it("highlights the code anyway", function() {
+        it("highlights the code anyway", function () {
           const code = "console.log('hi')";
           const result = highlight(code, { forceColor: true });
           const stripped = stripAnsi(result);
@@ -51,42 +51,42 @@ describe("@babel/highlight", function() {
     });
   });
 
-  describe("shouldHighlight", function() {
+  describe("shouldHighlight", function () {
-    describe("when colors are supported", function() {
+    describe("when colors are supported", function () {
       stubColorSupport(true);
 
-      it("returns true", function() {
+      it("returns true", function () {
         expect(shouldHighlight({})).toBeTruthy();
       });
     });
 
-    describe("when colors are not supported", function() {
+    describe("when colors are not supported", function () {
       stubColorSupport(false);
 
-      it("returns false", function() {
+      it("returns false", function () {
         expect(shouldHighlight({})).toBeFalsy();
       });
 
-      describe("and the forceColor option is passed", function() {
+      describe("and the forceColor option is passed", function () {
-        it("returns true", function() {
+        it("returns true", function () {
           expect(shouldHighlight({ forceColor: true })).toBeTruthy();
         });
       });
     });
   });
 
-  describe("getChalk", function() {
+  describe("getChalk", function () {
-    describe("when colors are supported", function() {
+    describe("when colors are supported", function () {
       stubColorSupport(true);
 
-      describe("when forceColor is not passed", function() {
+      describe("when forceColor is not passed", function () {
-        it("returns a Chalk instance", function() {
+        it("returns a Chalk instance", function () {
           expect(getChalk({}).constructor).toBe(chalk.constructor);
         });
       });
 
-      describe("when forceColor is passed", function() {
+      describe("when forceColor is passed", function () {
-        it("returns a Chalk instance", function() {
+        it("returns a Chalk instance", function () {
           expect(getChalk({ forceColor: true }).constructor).toBe(
             chalk.constructor,
           );
@@ -94,17 +94,17 @@ describe("@babel/highlight", function() {
       });
     });
 
-    describe("when colors are not supported", function() {
+    describe("when colors are not supported", function () {
       stubColorSupport(false);
 
-      describe("when forceColor is not passed", function() {
+      describe("when forceColor is not passed", function () {
-        it("returns a Chalk instance", function() {
+        it("returns a Chalk instance", function () {
           expect(getChalk({}).constructor).toBe(chalk.constructor);
         });
       });
 
-      describe("when forceColor is passed", function() {
+      describe("when forceColor is passed", function () {
-        it("returns a Chalk instance", function() {
+        it("returns a Chalk instance", function () {
           expect(getChalk({ forceColor: true }).constructor).toBe(
             chalk.constructor,
           );

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

@@ -120,7 +120,7 @@ const replPlugin = ({ types: t }) => ({
   },
 });
 
-const _eval = function(code, filename) {
+const _eval = function (code, filename) {
   code = code.trim();
   if (!code) return undefined;
 
@@ -162,7 +162,7 @@ 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;

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

@@ -45,7 +45,7 @@ const aliases = new Map([
   ["-gc", "--expose-gc"],
 ]);
 
-getV8Flags(function(err, v8Flags) {
+getV8Flags(function (err, v8Flags) {
   for (let i = 0; i < babelArgs.length; i++) {
     const arg = babelArgs[i];
     const flag = arg.split("=")[0];
@@ -87,8 +87,8 @@ getV8Flags(function(err, v8Flags) {
     const proc = child_process.spawn(process.argv[0], args, {
       stdio: "inherit",
     });
-    proc.on("exit", function(code, signal) {
+    proc.on("exit", function (code, signal) {
-      process.on("exit", function() {
+      process.on("exit", function () {
         if (signal) {
           process.kill(process.pid, signal);
         } else {

packages/babel-node/test/index.js

@@ -11,36 +11,36 @@ const fs = require("fs");
 const fixtureLoc = path.join(__dirname, "fixtures");
 const tmpLoc = path.join(__dirname, "tmp");
 
-const fileFilter = function(x) {
+const fileFilter = function (x) {
   return x !== ".DS_Store";
 };
 
-const outputFileSync = function(filePath, data) {
+const outputFileSync = function (filePath, data) {
   makeDirSync(path.dirname(filePath));
   fs.writeFileSync(filePath, data);
 };
 
-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();
 
@@ -71,7 +71,7 @@ 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 (!Object.prototype.hasOwnProperty.call(opts.inFiles, filename)) {
         const expected = opts.outFiles[filename];
         const actual = actualFiles[filename];
@@ -84,16 +84,16 @@ const assertTest = function(stdout, stderr, opts) {
       }
     });
 
-    Object.keys(opts.outFiles).forEach(function(filename) {
+    Object.keys(opts.outFiles).forEach(function (filename) {
       expect(actualFiles).toHaveProperty(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) {
     saveInFiles(opts.inFiles);
     let args = [binLoc];
     args.push("--config-file", "../config.json");
@@ -104,15 +104,15 @@ 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 {
@@ -136,11 +136,11 @@ const buildTest = function(binName, testName, opts) {
   };
 };
 
-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() {
+  describe("bin/" + binName, function () {
     let cwd;
 
     beforeEach(() => {
@@ -161,7 +161,7 @@ fs.readdirSync(fixtureLoc).forEach(function(binName) {
       process.chdir(cwd);
     });
 
-    fs.readdirSync(suiteLoc).forEach(function(testName) {
+    fs.readdirSync(suiteLoc).forEach(function (testName) {
       if (testName[0] === ".") return;
 
       const testLoc = path.join(suiteLoc, testName);
@@ -173,7 +173,7 @@ 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-parser/src/plugins/jsx/index.js

@@ -39,13 +39,13 @@ tt.jsxText = new TokenType("jsxText", { beforeExpr: true });
 tt.jsxTagStart = new TokenType("jsxTagStart", { startsExpr: true });
 tt.jsxTagEnd = new TokenType("jsxTagEnd");
 
-tt.jsxTagStart.updateContext = function() {
+tt.jsxTagStart.updateContext = function () {
   this.state.context.push(tc.j_expr); // treat as beginning of JSX expression
   this.state.context.push(tc.j_oTag); // start opening tag context
   this.state.exprAllowed = false;
 };
 
-tt.jsxTagEnd.updateContext = function(prevType) {
+tt.jsxTagEnd.updateContext = function (prevType) {
   const out = this.state.context.pop();
   if ((out === tc.j_oTag && prevType === tt.slash) || out === tc.j_cTag) {
     this.state.context.pop();

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

@@ -41,7 +41,7 @@ export const types: {
 
 // Token-specific context update code
 
-tt.parenR.updateContext = tt.braceR.updateContext = function() {
+tt.parenR.updateContext = tt.braceR.updateContext = function () {
   if (this.state.context.length === 1) {
     this.state.exprAllowed = true;
     return;
@@ -55,7 +55,7 @@ tt.parenR.updateContext = tt.braceR.updateContext = function() {
   this.state.exprAllowed = !out.isExpr;
 };
 
-tt.name.updateContext = function(prevType) {
+tt.name.updateContext = function (prevType) {
   let allowed = false;
   if (prevType !== tt.dot) {
     if (
@@ -75,19 +75,19 @@ tt.name.updateContext = function(prevType) {
   }
 };
 
-tt.braceL.updateContext = function(prevType) {
+tt.braceL.updateContext = function (prevType) {
   this.state.context.push(
     this.braceIsBlock(prevType) ? types.braceStatement : types.braceExpression,
   );
   this.state.exprAllowed = true;
 };
 
-tt.dollarBraceL.updateContext = function() {
+tt.dollarBraceL.updateContext = function () {
   this.state.context.push(types.templateQuasi);
   this.state.exprAllowed = true;
 };
 
-tt.parenL.updateContext = function(prevType) {
+tt.parenL.updateContext = function (prevType) {
   const statementParens =
     prevType === tt._if ||
     prevType === tt._for ||
@@ -99,11 +99,11 @@ tt.parenL.updateContext = function(prevType) {
   this.state.exprAllowed = true;
 };
 
-tt.incDec.updateContext = function() {
+tt.incDec.updateContext = function () {
   // tokExprAllowed stays unchanged
 };
 
-tt._function.updateContext = tt._class.updateContext = function(prevType) {
+tt._function.updateContext = tt._class.updateContext = function (prevType) {
   if (prevType === tt.dot || prevType === tt.questionDot) {
     // when function/class follows dot/questionDot, it is part of
     // (optional)MemberExpression, then we don't need to push new token context
@@ -128,7 +128,7 @@ tt._function.updateContext = tt._class.updateContext = function(prevType) {
   this.state.exprAllowed = false;
 };
 
-tt.backQuote.updateContext = function() {
+tt.backQuote.updateContext = function () {
   if (this.curContext() === types.template) {
     this.state.context.pop();
   } else {
@@ -137,6 +137,6 @@ tt.backQuote.updateContext = function() {
   this.state.exprAllowed = false;
 };
 
-tt.star.updateContext = function() {
+tt.star.updateContext = function () {
   this.state.exprAllowed = false;
 };

packages/babel-parser/test/helpers/runFixtureTests.js

@@ -26,8 +26,9 @@ class FixtureError extends Error {
           { highlightCode: true },
         ) +
         "\n" +
-        `at fixture (${fixturePath}:${previousError.loc.line}:${previousError
+        `at fixture (${fixturePath}:${previousError.loc.line}:${
-          .loc.column + 1})\n`;
+          previousError.loc.column + 1
+        })\n`;
     }
 
     this.stack =
@@ -36,22 +37,19 @@ class FixtureError extends Error {
       previousError.message +
       "\n" +
       fixtureStackFrame +
-      previousError.stack
+      previousError.stack.split("\n").slice(messageLines).join("\n");
-        .split("\n")
-        .slice(messageLines)
-        .join("\n");
   }
 }
 
 export function runFixtureTests(fixturesPath, parseFunction) {
   const fixtures = getFixtures(fixturesPath);
 
-  Object.keys(fixtures).forEach(function(name) {
+  Object.keys(fixtures).forEach(function (name) {
-    fixtures[name].forEach(function(testSuite) {
+    fixtures[name].forEach(function (testSuite) {
-      testSuite.tests.forEach(function(task) {
+      testSuite.tests.forEach(function (task) {
         const testFn = task.disabled ? it.skip : it;
 
-        testFn(name + "/" + testSuite.title + "/" + task.title, function() {
+        testFn(name + "/" + testSuite.title + "/" + task.title, function () {
           try {
             runTest(task, parseFunction);
           } catch (err) {
@@ -82,9 +80,9 @@ export function runFixtureTests(fixturesPath, parseFunction) {
 export function runThrowTestsWithEstree(fixturesPath, parseFunction) {
   const fixtures = getFixtures(fixturesPath);
 
-  Object.keys(fixtures).forEach(function(name) {
+  Object.keys(fixtures).forEach(function (name) {
-    fixtures[name].forEach(function(testSuite) {
+    fixtures[name].forEach(function (testSuite) {
-      testSuite.tests.forEach(function(task) {
+      testSuite.tests.forEach(function (task) {
         if (!task.options.throws) return;
 
         task.options.plugins = task.options.plugins || [];
@@ -92,7 +90,7 @@ export function runThrowTestsWithEstree(fixturesPath, parseFunction) {
 
         const testFn = task.disabled ? it.skip : it;
 
-        testFn(name + "/" + testSuite.title + "/" + task.title, function() {
+        testFn(name + "/" + testSuite.title + "/" + task.title, function () {
           try {
             runTest(task, parseFunction);
           } catch (err) {

packages/babel-parser/test/plugin-options.js

@@ -4,12 +4,12 @@ function getParser(code, plugins) {
   return () => parse(code, { plugins, sourceType: "module" });
 }
 
-describe("plugin options", function() {
+describe("plugin options", function () {
-  describe("the first options are used", function() {
+  describe("the first options are used", function () {
     // NOTE: This test is not specific about decorators, it can be applied
     // to any plugin with options.
 
-    it("when they aren't specified", function() {
+    it("when they aren't specified", function () {
       const WITHOUT_FLAG = "flow";
       const WITH_FLAG = ["flow", { all: true }];
 
@@ -52,7 +52,7 @@ describe("plugin options", function() {
       ).toMatchObject(AST_WITH_FLAG);
     });
 
-    it("when they are specified", function() {
+    it("when they are specified", function () {
       const NAME = "decorators";
       const OPT_1 = [NAME, { decoratorsBeforeExport: true }];
       const OPT_2 = [NAME, { decoratorsBeforeExport: false }];

packages/babel-plugin-proposal-async-generator-functions/src/for-await.js

@@ -33,7 +33,7 @@ const buildForAwait = template(`
   }
 `);
 
-export default function(path, { getAsyncIterator }) {
+export default function (path, { getAsyncIterator }) {
   const { node, scope, parent } = path;
 
   const stepKey = scope.generateUidIdentifier("step");

packages/babel-plugin-proposal-decorators/src/transformer-legacy.js

@@ -71,7 +71,7 @@ function applyClassDecorators(classPath) {
   return decorators
     .map(dec => dec.expression)
     .reverse()
-    .reduce(function(acc, decorator) {
+    .reduce(function (acc, decorator) {
       return buildClassDecorator({
         CLASS_REF: t.cloneNode(name),
         DECORATOR: t.cloneNode(decorator),
@@ -116,7 +116,7 @@ function applyTargetDecorators(path, state, decoratedProps) {
     path.isClass() ? "class" : "obj",
   );
 
-  const exprs = decoratedProps.reduce(function(acc, node) {
+  const exprs = decoratedProps.reduce(function (acc, node) {
     const decorators = node.decorators || [];
     node.decorators = null;
 

packages/babel-plugin-proposal-object-rest-spread/src/index.js

@@ -234,7 +234,7 @@ export default declare((api, opts) => {
         // example: f({...R}, a = R)
         let idInRest = false;
 
-        const IdentifierHandler = function(path, functionScope) {
+        const IdentifierHandler = function (path, functionScope) {
           const name = path.node.name;
           if (
             path.scope.getBinding(name) === functionScope.getBinding(name) &&

packages/babel-plugin-syntax-decorators/test/index.js

@@ -10,34 +10,34 @@ function makeParser(code, options) {
     });
 }
 
-describe("'legacy' option", function() {
+describe("'legacy' option", function () {
-  test("must be boolean", function() {
+  test("must be boolean", function () {
     expect(makeParser("", { legacy: "legacy" })).toThrow();
   });
 
-  test("'legacy': false", function() {
+  test("'legacy': false", function () {
     expect(makeParser("({ @dec fn() {} })", { legacy: false })).toThrow();
   });
 
-  test("'legacy': true", function() {
+  test("'legacy': true", function () {
     expect(makeParser("({ @dec fn() {} })", { legacy: true })).not.toThrow();
   });
 
-  test("defaults to 'false'", function() {
+  test("defaults to 'false'", function () {
     expect(makeParser("({ @dec fn() {} })", {})).toThrow();
   });
 });
 
-describe("'decoratorsBeforeExport' option", function() {
+describe("'decoratorsBeforeExport' option", function () {
-  test("must be boolean", function() {
+  test("must be boolean", function () {
     expect(makeParser("", { decoratorsBeforeExport: "before" })).toThrow();
   });
 
-  test("is required", function() {
+  test("is required", function () {
     expect(makeParser("", { legacy: false })).toThrow(/decoratorsBeforeExport/);
   });
 
-  test("is incompatible with legacy", function() {
+  test("is incompatible with legacy", function () {
     expect(
       makeParser("", { decoratorsBeforeExport: false, legacy: true }),
     ).toThrow();
@@ -59,7 +59,7 @@ describe("'decoratorsBeforeExport' option", function() {
       (code === BEFORE ? "before" : "after") +
       "export";
 
-    test(name, function() {
+    test(name, function () {
       const expectTheParser = expect(
         makeParser(code, { decoratorsBeforeExport: before }),
       );

packages/babel-plugin-transform-classes/src/transformClass.js

@@ -320,7 +320,7 @@ export default function transformClass(
 
     path.traverse(findThisesVisitor);
 
-    let thisRef = function() {
+    let thisRef = function () {
       const ref = path.scope.generateDeclaredUidIdentifier("this");
       thisRef = () => t.cloneNode(ref);
       return ref;
@@ -360,7 +360,7 @@ export default function transformClass(
       wrapSuperCall(bareSuper, classState.superName, thisRef, body);
 
       if (guaranteedSuperBeforeFinish) {
-        bareSuper.find(function(parentPath) {
+        bareSuper.find(function (parentPath) {
           // hit top so short circuit
           if (parentPath === path) {
             return true;

packages/babel-plugin-transform-computed-properties/src/index.js

@@ -159,7 +159,7 @@ export default declare((api, options) => {
 
           let mutatorRef;
 
-          const getMutatorId = function() {
+          const getMutatorId = function () {
             if (!mutatorRef) {
               mutatorRef = scope.generateUidIdentifier("mutatorMap");
 

packages/babel-plugin-transform-modules-commonjs/test/copied-nodes.js

@@ -1,6 +1,6 @@
 const babel = require("@babel/core");
 
-test("Doesn't use the same object for two different nodes in the AST", function() {
+test("Doesn't use the same object for two different nodes in the AST", function () {
   const code = 'import Foo from "bar"; Foo; Foo;';
 
   const ast = babel.transform(code, {

packages/babel-plugin-transform-modules-commonjs/test/esmodule-flag.js

@@ -1,7 +1,7 @@
 const babel = require("@babel/core");
 const vm = require("vm");
 
-test("Re-export doesn't overwrite __esModule flag", function() {
+test("Re-export doesn't overwrite __esModule flag", function () {
   let code = 'export * from "./dep";';
   const depStub = {
     __esModule: false,
@@ -11,7 +11,7 @@ test("Re-export doesn't overwrite __esModule flag", function() {
     module: {
       exports: {},
     },
-    require: function(id) {
+    require: function (id) {
       if (id === "./dep") return depStub;
       return require(id);
     },

packages/babel-plugin-transform-modules-systemjs/src/index.js

@@ -253,7 +253,7 @@ export default declare((api, options) => {
 
           function pushModule(source, key, specifiers) {
             let module;
-            modules.forEach(function(m) {
+            modules.forEach(function (m) {
               if (m.key === source) {
                 module = m;
               }
@@ -424,7 +424,7 @@ export default declare((api, options) => {
             }
           }
 
-          modules.forEach(function(specifiers) {
+          modules.forEach(function (specifiers) {
             let setterBody = [];
             const target = path.scope.generateUid(specifiers.key);
 

packages/babel-plugin-transform-named-capturing-groups-regex/src/index.js

@@ -1,7 +1,7 @@
 /* eslint-disable @babel/development/plugin-name */
 import { createRegExpFeaturePlugin } from "@babel/helper-create-regexp-features-plugin";
 
-export default function(core, options) {
+export default function (core, options) {
   const { runtime = true } = options;
   if (typeof runtime !== "boolean") {
     throw new Error("The 'runtime' option must be boolean");

packages/babel-plugin-transform-object-assign/src/index.js

@@ -7,7 +7,7 @@ export default declare(api => {
     name: "transform-object-assign",
 
     visitor: {
-      CallExpression: function(path, file) {
+      CallExpression: function (path, file) {
         if (path.get("callee").matchesPattern("Object.assign")) {
           path.node.callee = file.addHelper("extends");
         }

packages/babel-plugin-transform-property-mutators/src/index.js

@@ -22,7 +22,7 @@ export default declare(api => {
 
         const mutatorMap = {};
 
-        node.properties = node.properties.filter(function(prop) {
+        node.properties = node.properties.filter(function (prop) {
           if (!prop.computed && (prop.kind === "get" || prop.kind === "set")) {
             defineMap.push(mutatorMap, prop, null, file);
             return false;

packages/babel-plugin-transform-react-display-name/src/index.js

@@ -78,7 +78,7 @@ export default declare(api => {
         let id;
 
         // crawl up the ancestry looking for possible candidates for displayName inference
-        path.find(function(path) {
+        path.find(function (path) {
           if (path.isAssignmentExpression()) {
             id = path.node.left;
           } else if (path.isObjectProperty()) {

packages/babel-plugin-transform-react-jsx/src/transform-classic.js

@@ -92,7 +92,7 @@ export default declare((api, options) => {
     },
   };
 
-  visitor.JSXAttribute = function(path) {
+  visitor.JSXAttribute = function (path) {
     if (t.isJSXElement(path.node.value)) {
       path.node.value = t.jsxExpressionContainer(path.node.value);
     }

packages/babel-plugin-transform-runtime/scripts/build-dist.js

@@ -78,7 +78,7 @@ function writeCoreJS({
   }
 
   const runtimeRoot = proposals ? "core-js" : "core-js-stable";
-  paths.forEach(function(corejsPath) {
+  paths.forEach(function (corejsPath) {
     outputFile(
       path.join(pkgDirname, runtimeRoot, `${corejsPath}.js`),
       `module.exports = require("${corejsRoot}/${corejsPath}");`

packages/babel-plugin-transform-runtime/src/get-runtime-path/browser.js

@@ -1,4 +1,4 @@
-export default function(moduleName, dirname, absoluteRuntime) {
+export default function (moduleName, dirname, absoluteRuntime) {
   if (absoluteRuntime === false) return moduleName;
 
   throw new Error(

packages/babel-plugin-transform-runtime/src/get-runtime-path/index.js

@@ -1,7 +1,7 @@
 import path from "path";
 import resolve from "resolve";
 
-export default function(moduleName, dirname, absoluteRuntime) {
+export default function (moduleName, dirname, absoluteRuntime) {
   if (absoluteRuntime === false) return moduleName;
 
   return resolveAbsoluteRuntime(

packages/babel-plugin-transform-template-literals/src/index.js

@@ -25,7 +25,7 @@ export default declare((api, options) => {
    */
   function buildConcatCallExpressions(items) {
     let avail = true;
-    return items.reduce(function(left, right) {
+    return items.reduce(function (left, right) {
       let canBeInserted = t.isLiteral(right);
 
       if (!canBeInserted && avail) {

packages/babel-preset-env/src/get-option-specific-excludes.js

@@ -2,6 +2,6 @@
 
 const defaultExcludesForLooseMode = ["transform-typeof-symbol"];
 
-export default function({ loose }: { loose: boolean }): null | string[] {
+export default function ({ loose }: { loose: boolean }): null | string[] {
   return loose ? defaultExcludesForLooseMode : null;
 }

packages/babel-preset-env/src/polyfills/corejs2/entry-plugin.js

@@ -14,7 +14,7 @@ import { logEntryPolyfills } from "../../debug";
 import type { InternalPluginOptions } from "../../types";
 import type { NodePath } from "@babel/traverse";
 
-export default function(
+export default function (
   _: any,
   {
     include,
@@ -53,7 +53,7 @@ export default function(
     pre() {
       this.importPolyfillIncluded = false;
 
-      this.replaceBySeparateModulesImport = function(path) {
+      this.replaceBySeparateModulesImport = function (path) {
         this.importPolyfillIncluded = true;
 
         if (regenerator) {

packages/babel-preset-env/src/polyfills/corejs2/get-platform-specific-default.js

@@ -8,7 +8,7 @@ export const defaultWebIncludes = [
   "web.dom.iterable",
 ];
 
-export default function(targets: Targets): null | string[] {
+export default function (targets: Targets): null | string[] {
   const targetNames = Object.keys(targets);
   const isAnyTarget = !targetNames.length;
   const isWebTarget = targetNames.some(name => name !== "node");

packages/babel-preset-env/src/polyfills/corejs2/usage-plugin.js

@@ -26,7 +26,7 @@ const NO_DIRECT_POLYFILL_IMPORT = `
   When setting \`useBuiltIns: 'usage'\`, polyfills are automatically imported when needed.
   Please remove the \`import '@babel/polyfill'\` call or use \`useBuiltIns: 'entry'\` instead.`;
 
-export default function(
+export default function (
   { types: t }: { types: Object },
   { include, exclude, polyfillTargets, debug }: InternalPluginOptions,
 ) {
@@ -191,14 +191,14 @@ export default function(
     pre({ path }: { path: NodePath }) {
       this.polyfillsSet = new Set();
 
-      this.addImport = function(builtIn) {
+      this.addImport = function (builtIn) {
         if (!this.polyfillsSet.has(builtIn)) {
           this.polyfillsSet.add(builtIn);
           createImport(path, builtIn);
         }
       };
 
-      this.addUnsupported = function(builtIn) {
+      this.addUnsupported = function (builtIn) {
         const modules = Array.isArray(builtIn) ? builtIn : [builtIn];
         for (const module of modules) {
           if (polyfills.has(module)) {

packages/babel-preset-env/src/polyfills/corejs3/entry-plugin.js

@@ -35,7 +35,7 @@ const BABEL_POLYFILL_DEPRECATION = `
   \`@babel/polyfill\` is deprecated. Please, use required parts of \`core-js\`
   and \`regenerator-runtime/runtime\` separately`;
 
-export default function(
+export default function (
   _: any,
   { corejs, include, exclude, polyfillTargets, debug }: InternalPluginOptions,
 ) {
@@ -115,7 +115,7 @@ export default function(
       this.injectedPolyfills = new Set();
       this.polyfillsSet = new Set();
 
-      this.replaceBySeparateModulesImport = function(path, modules) {
+      this.replaceBySeparateModulesImport = function (path, modules) {
         for (const module of modules) {
           this.polyfillsSet.add(module);
         }

packages/babel-preset-env/src/polyfills/corejs3/usage-plugin.js

@@ -47,7 +47,7 @@ const corejs3PolyfillsWithShippedProposals = (corejs3ShippedProposalsList: strin
   { ...corejs3PolyfillsWithoutProposals },
 );
 
-export default function(
+export default function (
   _: any,
   {
     corejs,
@@ -234,21 +234,21 @@ export default function(
       this.injectedPolyfills = new Set();
       this.polyfillsSet = new Set();
 
-      this.addUnsupported = function(builtIn) {
+      this.addUnsupported = function (builtIn) {
         const modules = Array.isArray(builtIn) ? builtIn : [builtIn];
         for (const module of modules) {
           this.polyfillsSet.add(module);
         }
       };
 
-      this.addBuiltInDependencies = function(builtIn) {
+      this.addBuiltInDependencies = function (builtIn) {
         if (has(BuiltIns, builtIn)) {
           const BuiltInDependencies = BuiltIns[builtIn];
           this.addUnsupported(BuiltInDependencies);
         }
       };
 
-      this.addPropertyDependencies = function(source = {}, key) {
+      this.addPropertyDependencies = function (source = {}, key) {
         const { builtIn, instanceType, isNamespaced } = source;
         if (isNamespaced) return;
         if (PossibleGlobalObjects.has(builtIn)) {

packages/babel-preset-env/src/polyfills/regenerator/entry-plugin.js

@@ -7,7 +7,7 @@ function isRegeneratorSource(source) {
   return source === "regenerator-runtime/runtime";
 }
 
-export default function() {
+export default function () {
   const visitor = {
     ImportDeclaration(path: NodePath) {
       if (isRegeneratorSource(getImportSource(path))) {

packages/babel-preset-env/src/polyfills/regenerator/usage-plugin.js

@@ -3,7 +3,7 @@
 import { createImport } from "../../utils";
 import type { NodePath } from "@babel/traverse";
 
-export default function() {
+export default function () {
   return {
     name: "regenerator-usage",
     pre() {

packages/babel-preset-env/src/utils.js

@@ -8,10 +8,7 @@ import type { Targets } from "@babel/helper-compilation-targets";
 export const has = Object.hasOwnProperty.call.bind(Object.hasOwnProperty);
 
 export function getType(target: any): string {
-  return Object.prototype.toString
+  return Object.prototype.toString.call(target).slice(8, -1).toLowerCase();
-    .call(target)
-    .slice(8, -1)
-    .toLowerCase();
 }
 
 export function intersection<T>(

packages/babel-preset-env/test/normalize-options.spec.js

@@ -214,8 +214,8 @@ describe("normalize-options", () => {
     });
   });
 
-  describe("checkDuplicateIncludeExcludes", function() {
+  describe("checkDuplicateIncludeExcludes", function () {
-    it("should throw if duplicate names in both", function() {
+    it("should throw if duplicate names in both", function () {
       expect(() => {
         checkDuplicateIncludeExcludes(
           ["transform-regenerator", "map"],
@@ -224,7 +224,7 @@ describe("normalize-options", () => {
       }).toThrow();
     });
 
-    it("should not throw if no duplicate names in both", function() {
+    it("should not throw if no duplicate names in both", function () {
       expect(() => {
         checkDuplicateIncludeExcludes(["transform-regenerator"], ["map"]);
       }).not.toThrow();