How to use loadBabelConfig method in Jest
Best JavaScript code snippet using jest
config.js
Source:config.js 
...11 presets.splice(index, 1);12 }13}14// Tries to load a .babelrc and returns the parsed object if successful15function loadBabelConfig(babelConfigPath) {16 let config;17 if (fs.existsSync(babelConfigPath)) {18 const content = fs.readFileSync(babelConfigPath, 'utf-8');19 try {20 config = JSON5.parse(content);21 config.babelrc = false;22 } catch (e) {23 logger.error(`=> Error parsing .babelrc file: ${e.message}`);24 throw e;25 }26 }27 if (!config) return null;28 // Remove react-hmre preset.29 // It causes issues with react-storybook.30 // We don't really need it.31 // Earlier, we fix this by runnign storybook in the production mode.32 // But, that hide some useful debug messages.33 if (config.presets) {34 removeReactHmre(config.presets);35 }36 if (config.env && config.env.development && config.env.development.presets) {37 removeReactHmre(config.env.development.presets);38 }39 return config;40}41// `baseConfig` is a webpack configuration bundled with storybook.42// Storybook will look in the `configDir` directory43// (inside working directory) if a config path is not provided.44export default function(configType, baseConfig, projectDir, configDir) {45 const config = baseConfig;46 // Search for a .babelrc in project directory, config directory, and storybook47 // module directory. If found, use that to extend webpack configurations.48 const babelConfigInConfig = loadBabelConfig(path.resolve(configDir, '.babelrc'));49 const babelConfigInProject = loadBabelConfig(path.resolve(projectDir, '.babelrc'));50 const babelConfigInModule = loadBabelConfig('.babelrc');51 let babelConfig = null;52 let babelConfigDir = '';53 if (babelConfigInConfig) {54 logger.info('=> Loading custom .babelrc from config directory.');55 babelConfig = babelConfigInConfig;56 babelConfigDir = configDir;57 } else if (babelConfigInProject) {58 logger.info('=> Loading custom .babelrc from project directory.');59 babelConfig = babelConfigInProject;60 babelConfigDir = projectDir;61 } else {62 babelConfig = babelConfigInModule;63 }64 if (babelConfig) {...
make-cache.js
Source:make-cache.js
...71 }72 }73 return configPath74 }75 function loadBabelConfig(editor) {76 if (!configCache.has(editor)) {77 let babelConfig: ?Object = undefined78 const configPath = findConfigFile(editor)79 if (configPath != null) {80 debug("loadBabelConfig", configPath)81 try {82 if (path.extname(configPath) === ".js") {83 const dontCache = {}84 const requireIfTrusted = makeRequire(trusted => {85 if (trusted === false) {86 return undefined87 }88 if (trusted === true) {89 data.delete(editor)90 configCache.delete(editor)91 }92 return dontCache93 })94 // $FlowExpectError95 const cfg = requireIfTrusted(configPath)96 debug("cfg", cfg)97 babelConfig = typeof cfg === "function" ? cfg() : cfg98 if (babelConfig === dontCache) {99 return undefined100 }101 } else {102 babelConfig = JSON.parse(String(fs.readFileSync(configPath)))103 }104 if (babelConfig) {105 babelConfig.cwd = babelConfig.cwd || path.dirname(configPath)106 const babel = require("@babel/core")107 babelConfig = babel.loadOptions(babelConfig)108 }109 } catch (e) {110 debug("loadBabelConfig error", e)111 }112 debug("babel config", babelConfig)113 }114 configCache.set(editor, babelConfig)115 }116 return configCache.get(editor)117 }118 function watchEditor(editor) {119 if (!editors.has(editor)) {120 editors.set(editor, null)121 subscriptions.add(122 editor.onDidStopChanging(() => {123 data.delete(editor)124 }),125 )126 }127 }128 return {129 get(editor: TextEditor): Info {130 watchEditor(editor)131 if (!data.has(editor)) {132 data.set(editor, parseCode(editor.getText(), loadBabelConfig(editor)))133 }134 // $FlowExpectError - Flow thinks it might return null here135 return data.get(editor)136 },137 }...
index.js
Source:index.js
...44 filename: Path,45 configString: string,46 {config, instrument, rootDir}: {config: ProjectConfig} & CacheKeyOptions,47 ): string {48 const babelOptions = loadBabelConfig(config.cwd, filename);49 const configPath = [50 babelOptions.config || '',51 babelOptions.babelrc || '',52 ];53 return crypto54 .createHash('md5')55 .update(THIS_FILE)56 .update('\0', 'utf8')57 .update(JSON.stringify(babelOptions.options))58 .update('\0', 'utf8')59 .update(fileData)60 .update('\0', 'utf8')61 .update(path.relative(rootDir, filename))62 .update('\0', 'utf8')63 .update(configString)64 .update('\0', 'utf8')65 .update(configPath.join(''))66 .update('\0', 'utf8')67 .update(instrument ? 'instrument' : '')68 .update('\0', 'utf8')69 .update(process.env.NODE_ENV || '')70 .update('\0', 'utf8')71 .update(process.env.BABEL_ENV || '')72 .digest('hex');73 },74 process(75 src: string,76 filename: Path,77 config: ProjectConfig,78 transformOptions?: TransformOptions,79 ): string | TransformedSource {80 const babelOptions = {...loadBabelConfig(config.cwd, filename).options};81 if (transformOptions && transformOptions.instrument) {82 babelOptions.auxiliaryCommentBefore = ' istanbul ignore next ';83 // Copied from jest-runtime transform.js84 babelOptions.plugins = babelOptions.plugins.concat([85 [86 babelIstanbulPlugin,87 {88 // files outside `cwd` will not be instrumented89 cwd: config.rootDir,90 exclude: [],91 },92 ],93 ]);94 }...
babel-jest.js
Source:babel-jest.js
...33 filename,34 configString,35 { config, instrument, rootDir }36 ) {37 const babelOptions = loadBabelConfig(38 JSON.parse(configString).cwd,39 filename40 );41 const configPath = [42 babelOptions.config || '',43 babelOptions.babelrc || ''44 ];45 return crypto46 .createHash('md5')47 .update(THIS_FILE)48 .update('\0', 'utf8')49 .update(JSON.stringify(babelOptions.options))50 .update('\0', 'utf8')51 .update(fileData)52 .update('\0', 'utf8')53 .update(path.relative(rootDir, filename))54 .update('\0', 'utf8')55 .update(configString)56 .update('\0', 'utf8')57 .update(configPath.join(''))58 .update('\0', 'utf8')59 .update(instrument ? 'instrument' : '')60 .update('\0', 'utf8')61 .update(process.env.NODE_ENV || '')62 .update('\0', 'utf8')63 .update(process.env.BABEL_ENV || '')64 .digest('hex');65 },66 process(src, filename, config, transformOptions) {67 const babelOptions = { ...loadBabelConfig(config.cwd, filename).options };68 if (transformOptions && transformOptions.instrument) {69 babelOptions.auxiliaryCommentBefore = ' istanbul ignore next ';70 // Copied from jest-runtime transform.js71 babelOptions.plugins = babelOptions.plugins.concat([72 [73 babelIstanbulPlugin,74 {75 // files outside `cwd` will not be instrumented76 cwd: config.rootDir,77 exclude: []78 }79 ]80 ]);81 }...
babel_config.test.js
Source:babel_config.test.js
...26 ]27 }`,28 },29 });30 const config = loadBabelConfig('.foo');31 expect(config).toEqual({32 babelrc: false,33 plugins: [34 'foo-plugin',35 [36 babelPluginReactDocgenPath,37 {38 DOC_GEN_COLLECTION_NAME: 'STORYBOOK_REACT_CLASSES',39 },40 ],41 ],42 presets: ['env', 'foo-preset'],43 });44 });45 it('should return the config with the extra plugins when `plugins` is not an array.', () => {46 setup({47 files: {48 '.babelrc': `{49 "presets": [50 "env",51 "foo-preset"52 ],53 "plugins": "bar-plugin"54 }`,55 },56 });57 const config = loadBabelConfig('.bar');58 expect(config).toEqual({59 babelrc: false,60 plugins: [61 'bar-plugin',62 [63 babelPluginReactDocgenPath,64 {65 DOC_GEN_COLLECTION_NAME: 'STORYBOOK_REACT_CLASSES',66 },67 ],68 ],69 presets: ['env', 'foo-preset'],70 });71 });72 it('should return the config only with the extra plugins when `plugins` is not present.', () => {73 // Mock a `.babelrc` config file with no plugins key.74 setup({75 files: {76 '.babelrc': `{77 "presets": [78 "env",79 "foo-preset"80 ]81 }`,82 },83 });84 const config = loadBabelConfig('.biz');85 expect(config).toEqual({86 babelrc: false,87 plugins: [88 [89 babelPluginReactDocgenPath,90 {91 DOC_GEN_COLLECTION_NAME: 'STORYBOOK_REACT_CLASSES',92 },93 ],94 ],95 presets: ['env', 'foo-preset'],96 });97 });98});
jest.config.js
Source:jest.config.js
1const { createConfigItem } = require('@babel/core');2const { loadBabelConfig, loadCoreConfig, loadCoreConfigFiles } = require('wc-bundler');3const babel = loadBabelConfig(loadCoreConfig(loadCoreConfigFiles(undefined)).babel, {4 env: { targets: { node: '12' } },5 typescript: true,6});7makeBabelPluginConfigSerializable(babel.plugins);8makeBabelPluginConfigSerializable(babel.presets);9/** @type {import('@jest/types').Config.InitialOptions} */10const config = {11 coveragePathIgnorePatterns: [/\/node_modules\//.source, /\/\S*fixture\S*\//.source],12 transform: { [/\.[jt]sx?$/.source]: ['babel-jest', babel] },13};14module.exports = config;15/**16 * Jest å¯ç¨ worker æ§è¡æµè¯ç¨ä¾æ¶ï¼ babel ç ConfigItem æ æ³è¢«åºååä¼ å
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babel-jest_vx.x.x.js
Source:babel-jest_vx.x.x.js
1// flow-typed signature: 4c5da1c3fe02232aa441a60ecf7ce8cd2// flow-typed version: <<STUB>>/babel-jest_v^27.4.6/flow_v0.130.03/**4 * This is an autogenerated libdef stub for:5 *6 * 'babel-jest'7 *8 * Fill this stub out by replacing all the `any` types.9 *10 * Once filled out, we encourage you to share your work with the11 * community by sending a pull request to:12 * https://github.com/flowtype/flow-typed13 */14declare module 'babel-jest' {15 declare module.exports: any;16}17/**18 * We include stubs for each file inside this npm package in case you need to19 * require those files directly. Feel free to delete any files that aren't20 * needed.21 */22declare module 'babel-jest/build' {23 declare module.exports: any;24}25declare module 'babel-jest/build/loadBabelConfig' {26 declare module.exports: any;27}28// Filename aliases29declare module 'babel-jest/build/index' {30 declare module.exports: $Exports<'babel-jest/build'>;31}32declare module 'babel-jest/build/index.js' {33 declare module.exports: $Exports<'babel-jest/build'>;34}35declare module 'babel-jest/build/loadBabelConfig.js' {36 declare module.exports: $Exports<'babel-jest/build/loadBabelConfig'>;...
jest.babel.js
Source:jest.babel.js
1const { createHash } = require('crypto');2const { createTransformer } = require('babel-jest');3const path = require('path')4const { existsSync } = require('fs-extra')5function loadBabelConfig() {6 const babelConfigPath = path.resolve(process.cwd(), 'babel.config')7 if (existsSync(babelConfigPath)) {8 return require(babelConfigPath)9 }10 return {};11}12module.exports = {13 canInstrument: true,14 getCacheKey(sourceText) {15 const babelOptions = loadBabelConfig();16 return createHash('md5')17 .update('\0', 'utf8')18 .update(JSON.stringify(babelOptions))19 .update('\0', 'utf8')20 .update(sourceText)21 .update('\0', 'utf8')22 .update('components')23 .update('\0', 'utf8')24 .digest('hex');25 },26 process(sourceText, sourcePath, transformOptions) {27 const babelOptions = loadBabelConfig();28 const babelJest = createTransformer(babelOptions);29 return babelJest.process(sourceText, sourcePath, transformOptions);30 },...
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