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How to use assertSyncTransformer method in Jest

Best JavaScript code snippet using jest

ScriptTransformer.js

Source:ScriptTransformer.js

...506    let processed = null;507    let shouldCallTransform = false;508    if (transformer && this.shouldTransform(filename)) {509      shouldCallTransform = true;510      assertSyncTransformer(transformer, this._getTransformPath(filename));511      processed = transformer.process(content, filename, {512        ...options,513        cacheFS: this._cacheFS,514        config: this._config,515        configString: this._cache.configString,516        transformerConfig517      });518    }519    return this._buildTransformResult(520      filename,521      cacheFilePath,522      content,523      transformer,524      shouldCallTransform,525      options,526      processed,527      sourceMapPath528    );529  }530  async transformSourceAsync(filepath, content, options) {531    const filename = (0, _jestUtil().tryRealpath)(filepath);532    const {transformer, transformerConfig = {}} =533      this._getTransformer(filename) || {};534    const cacheFilePath = await this._getFileCachePathAsync(535      filename,536      content,537      options538    );539    const sourceMapPath = cacheFilePath + '.map'; // Ignore cache if `config.cache` is set (--no-cache)540    const code = this._config.cache ? readCodeCacheFile(cacheFilePath) : null;541    if (code) {542      // This is broken: we return the code, and a path for the source map543      // directly from the cache. But, nothing ensures the source map actually544      // matches that source code. They could have gotten out-of-sync in case545      // two separate processes write concurrently to the same cache files.546      return {547        code,548        originalCode: content,549        sourceMapPath550      };551    }552    let processed = null;553    let shouldCallTransform = false;554    if (transformer && this.shouldTransform(filename)) {555      shouldCallTransform = true;556      const process = transformer.processAsync || transformer.process; // This is probably dead code since `_getTransformerAsync` already asserts this557      invariant(558        typeof process === 'function',559        'A transformer must always export either a `process` or `processAsync`'560      );561      processed = await process(content, filename, {562        ...options,563        cacheFS: this._cacheFS,564        config: this._config,565        configString: this._cache.configString,566        transformerConfig567      });568    }569    return this._buildTransformResult(570      filename,571      cacheFilePath,572      content,573      transformer,574      shouldCallTransform,575      options,576      processed,577      sourceMapPath578    );579  }580  async _transformAndBuildScriptAsync(581    filename,582    options,583    transformOptions,584    fileSource585  ) {586    const {isInternalModule} = options;587    let fileContent =588      fileSource !== null && fileSource !== void 0589        ? fileSource590        : this._cacheFS.get(filename);591    if (!fileContent) {592      fileContent = fs().readFileSync(filename, 'utf8');593      this._cacheFS.set(filename, fileContent);594    }595    const content = stripShebang(fileContent);596    let code = content;597    let sourceMapPath = null;598    const willTransform =599      !isInternalModule &&600      (transformOptions.instrument || this.shouldTransform(filename));601    try {602      if (willTransform) {603        const transformedSource = await this.transformSourceAsync(604          filename,605          content,606          transformOptions607        );608        code = transformedSource.code;609        sourceMapPath = transformedSource.sourceMapPath;610      }611      return {612        code,613        originalCode: content,614        sourceMapPath615      };616    } catch (e) {617      throw (0, _enhanceUnexpectedTokenMessage.default)(e);618    }619  }620  _transformAndBuildScript(filename, options, transformOptions, fileSource) {621    const {isInternalModule} = options;622    let fileContent =623      fileSource !== null && fileSource !== void 0624        ? fileSource625        : this._cacheFS.get(filename);626    if (!fileContent) {627      fileContent = fs().readFileSync(filename, 'utf8');628      this._cacheFS.set(filename, fileContent);629    }630    const content = stripShebang(fileContent);631    let code = content;632    let sourceMapPath = null;633    const willTransform =634      !isInternalModule &&635      (transformOptions.instrument || this.shouldTransform(filename));636    try {637      if (willTransform) {638        const transformedSource = this.transformSource(639          filename,640          content,641          transformOptions642        );643        code = transformedSource.code;644        sourceMapPath = transformedSource.sourceMapPath;645      }646      return {647        code,648        originalCode: content,649        sourceMapPath650      };651    } catch (e) {652      throw (0, _enhanceUnexpectedTokenMessage.default)(e);653    }654  }655  async transformAsync(filename, options, fileSource) {656    const instrument =657      options.coverageProvider === 'babel' &&658      (0, _shouldInstrument.default)(filename, options, this._config);659    const scriptCacheKey = getScriptCacheKey(filename, instrument);660    let result = this._cache.transformedFiles.get(scriptCacheKey);661    if (result) {662      return result;663    }664    result = await this._transformAndBuildScriptAsync(665      filename,666      options,667      {...options, instrument},668      fileSource669    );670    if (scriptCacheKey) {671      this._cache.transformedFiles.set(scriptCacheKey, result);672    }673    return result;674  }675  transform(filename, options, fileSource) {676    const instrument =677      options.coverageProvider === 'babel' &&678      (0, _shouldInstrument.default)(filename, options, this._config);679    const scriptCacheKey = getScriptCacheKey(filename, instrument);680    let result = this._cache.transformedFiles.get(scriptCacheKey);681    if (result) {682      return result;683    }684    result = this._transformAndBuildScript(685      filename,686      options,687      {...options, instrument},688      fileSource689    );690    if (scriptCacheKey) {691      this._cache.transformedFiles.set(scriptCacheKey, result);692    }693    return result;694  }695  transformJson(filename, options, fileSource) {696    const {isInternalModule} = options;697    const willTransform = !isInternalModule && this.shouldTransform(filename);698    if (willTransform) {699      const {code: transformedJsonSource} = this.transformSource(700        filename,701        fileSource,702        {...options, instrument: false}703      );704      return transformedJsonSource;705    }706    return fileSource;707  }708  async requireAndTranspileModule(709    moduleName,710    callback,711    options = {712      applyInteropRequireDefault: true,713      instrument: false,714      supportsDynamicImport: false,715      supportsExportNamespaceFrom: false,716      supportsStaticESM: false,717      supportsTopLevelAwait: false718    }719  ) {720    let transforming = false;721    const {applyInteropRequireDefault, ...transformOptions} = options;722    const revertHook = (0, _pirates().addHook)(723      (code, filename) => {724        try {725          transforming = true;726          return (727            this.transformSource(filename, code, transformOptions).code || code728          );729        } finally {730          transforming = false;731        }732      },733      {734        exts: this._config.moduleFileExtensions.map(ext => `.${ext}`),735        ignoreNodeModules: false,736        matcher: filename => {737          if (transforming) {738            // Don't transform any dependency required by the transformer itself739            return false;740          }741          return this.shouldTransform(filename);742        }743      }744    );745    try {746      const module = await (0, _jestUtil().requireOrImportModule)(747        moduleName,748        applyInteropRequireDefault749      );750      if (!callback) {751        revertHook();752        return module;753      }754      const cbResult = callback(module);755      if ((0, _jestUtil().isPromise)(cbResult)) {756        return waitForPromiseWithCleanup(cbResult, revertHook).then(757          () => module758        );759      }760      return module;761    } finally {762      revertHook();763    }764  }765  shouldTransform(filename) {766    const ignoreRegexp = this._cache.ignorePatternsRegExp;767    const isIgnored = ignoreRegexp ? ignoreRegexp.test(filename) : false;768    return this._config.transform.length !== 0 && !isIgnored;769  }770} // TODO: do we need to define the generics twice?771async function createTranspilingRequire(config) {772  const transformer = await createScriptTransformer(config);773  return async function requireAndTranspileModule(774    resolverPath,775    applyInteropRequireDefault = false776  ) {777    const transpiledModule = await transformer.requireAndTranspileModule(778      resolverPath,779      () => {},780      {781        applyInteropRequireDefault,782        instrument: false,783        supportsDynamicImport: false,784        // this might be true, depending on node version.785        supportsExportNamespaceFrom: false,786        supportsStaticESM: false,787        supportsTopLevelAwait: false788      }789    );790    return transpiledModule;791  };792}793const removeFile = path => {794  try {795    fs().unlinkSync(path);796  } catch {}797};798const stripShebang = content => {799  // If the file data starts with a shebang remove it. Leaves the empty line800  // to keep stack trace line numbers correct.801  if (content.startsWith('#!')) {802    return content.replace(/^#!.*/, '');803  } else {804    return content;805  }806};807/**808 * This is like `writeCacheFile` but with an additional sanity checksum. We809 * cannot use the same technique for source maps because we expose source map810 * cache file paths directly to callsites, with the expectation they can read811 * it right away. This is not a great system, because source map cache file812 * could get corrupted, out-of-sync, etc.813 */814function writeCodeCacheFile(cachePath, code) {815  const checksum = (0, _crypto().createHash)('md5').update(code).digest('hex');816  writeCacheFile(cachePath, checksum + '\n' + code);817}818/**819 * Read counterpart of `writeCodeCacheFile`. We verify that the content of the820 * file matches the checksum, in case some kind of corruption happened. This821 * could happen if an older version of `jest-runtime` writes non-atomically to822 * the same cache, for example.823 */824function readCodeCacheFile(cachePath) {825  const content = readCacheFile(cachePath);826  if (content == null) {827    return null;828  }829  const code = content.substring(33);830  const checksum = (0, _crypto().createHash)('md5').update(code).digest('hex');831  if (checksum === content.substring(0, 32)) {832    return code;833  }834  return null;835}836/**837 * Writing to the cache atomically relies on 'rename' being atomic on most838 * file systems. Doing atomic write reduces the risk of corruption by avoiding839 * two processes to write to the same file at the same time. It also reduces840 * the risk of reading a file that's being overwritten at the same time.841 */842const writeCacheFile = (cachePath, fileData) => {843  try {844    (0, _writeFileAtomic().sync)(cachePath, fileData, {845      encoding: 'utf8',846      fsync: false847    });848  } catch (e) {849    if (cacheWriteErrorSafeToIgnore(e, cachePath)) {850      return;851    }852    e.message =853      'jest: failed to cache transform results in: ' +854      cachePath +855      '\nFailure message: ' +856      e.message;857    removeFile(cachePath);858    throw e;859  }860};861/**862 * On Windows, renames are not atomic, leading to EPERM exceptions when two863 * processes attempt to rename to the same target file at the same time.864 * If the target file exists we can be reasonably sure another process has865 * legitimately won a cache write race and ignore the error.866 */867const cacheWriteErrorSafeToIgnore = (e, cachePath) =>868  process.platform === 'win32' &&869  e.code === 'EPERM' &&870  fs().existsSync(cachePath);871const readCacheFile = cachePath => {872  if (!fs().existsSync(cachePath)) {873    return null;874  }875  let fileData;876  try {877    fileData = fs().readFileSync(cachePath, 'utf8');878  } catch (e) {879    e.message =880      'jest: failed to read cache file: ' +881      cachePath +882      '\nFailure message: ' +883      e.message;884    removeFile(cachePath);885    throw e;886  }887  if (fileData == null) {888    // We must have somehow created the file but failed to write to it,889    // let's delete it and retry.890    removeFile(cachePath);891  }892  return fileData;893};894const getScriptCacheKey = (filename, instrument) => {895  const mtime = fs().statSync(filename).mtime;896  return filename + '_' + mtime.getTime() + (instrument ? '_instrumented' : '');897};898const calcIgnorePatternRegExp = config => {899  if (900    !config.transformIgnorePatterns ||901    config.transformIgnorePatterns.length === 0902  ) {903    return undefined;904  }905  return new RegExp(config.transformIgnorePatterns.join('|'));906};907const calcTransformRegExp = config => {908  if (!config.transform.length) {909    return undefined;910  }911  const transformRegexp = [];912  for (let i = 0; i < config.transform.length; i++) {913    transformRegexp.push([914      new RegExp(config.transform[i][0]),915      config.transform[i][1],916      config.transform[i][2]917    ]);918  }919  return transformRegexp;920};921function invariant(condition, message) {922  if (!condition) {923    throw new Error(message);924  }925}926function assertSyncTransformer(transformer, name) {927  invariant(name);928  invariant(929    typeof transformer.process === 'function',930    (0, _runtimeErrorsAndWarnings.makeInvalidSyncTransformerError)(name)931  );932}933async function createScriptTransformer(config, cacheFS = new Map()) {934  const transformer = new ScriptTransformer(config, cacheFS);935  await transformer.loadTransformers();936  return transformer;...

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