How to use stripAddedIndentation method in Jest

Best JavaScript code snippet using jest

index.js

Source:index.js

...72    count +73    '`'74  );75};76function stripAddedIndentation(inlineSnapshot) {77  // Find indentation if exists.78  const match = inlineSnapshot.match(INDENTATION_REGEX);79  if (!match || !match[1]) {80    // No indentation.81    return inlineSnapshot;82  }83  const indentation = match[1];84  const lines = inlineSnapshot.split('\n');85  if (lines.length <= 2) {86    // Must be at least 3 lines.87    return inlineSnapshot;88  }89  if (lines[0].trim() !== '' || lines[lines.length - 1].trim() !== '') {90    // If not blank first and last lines, abort.91    return inlineSnapshot;92  }93  for (let i = 1; i < lines.length - 1; i++) {94    if (lines[i] !== '') {95      if (lines[i].indexOf(indentation) !== 0) {96        // All lines except first and last should either be blank or have the same97        // indent as the first line (or more). If this isn't the case we don't98        // want to touch the snapshot at all.99        return inlineSnapshot;100      }101      lines[i] = lines[i].substr(indentation.length);102    }103  } // Last line is a special case because it won't have the same indent as others104  // but may still have been given some indent to line up.105  lines[lines.length - 1] = ''; // Return inline snapshot, now at indent 0.106  inlineSnapshot = lines.join('\n');107  return inlineSnapshot;108}109const fileExists = (filePath, hasteFS) =>110  hasteFS.exists(filePath) || jestExistsFile(filePath);111const cleanup = (hasteFS, update, snapshotResolver, testPathIgnorePatterns) => {112  const pattern = '\\.' + _SnapshotResolver.EXTENSION + '$';113  const files = hasteFS.matchFiles(pattern);114  let testIgnorePatternsRegex = null;115  if (testPathIgnorePatterns && testPathIgnorePatterns.length > 0) {116    testIgnorePatternsRegex = new RegExp(testPathIgnorePatterns.join('|'));117  }118  const list = files.filter(snapshotFile => {119    const testPath = snapshotResolver.resolveTestPath(snapshotFile); // ignore snapshots of ignored tests120    if (testIgnorePatternsRegex && testIgnorePatternsRegex.test(testPath)) {121      return false;122    }123    if (!fileExists(testPath, hasteFS)) {124      if (update === 'all') {125        fs.unlinkSync(snapshotFile);126      }127      return true;128    }129    return false;130  });131  return {132    filesRemoved: list.length,133    filesRemovedList: list134  };135};136const toMatchSnapshot = function (received, propertiesOrHint, hint) {137  const matcherName = 'toMatchSnapshot';138  let properties;139  const length = arguments.length;140  if (length === 2 && typeof propertiesOrHint === 'string') {141    hint = propertiesOrHint;142  } else if (length >= 2) {143    if (typeof propertiesOrHint !== 'object' || propertiesOrHint === null) {144      const options = {145        isNot: this.isNot,146        promise: this.promise147      };148      let printedWithType = (0, _jestMatcherUtils.printWithType)(149        'Expected properties',150        propertiesOrHint,151        _printSnapshot.printExpected152      );153      if (length === 3) {154        options.secondArgument = 'hint';155        options.secondArgumentColor = _jestMatcherUtils.BOLD_WEIGHT;156        if (propertiesOrHint == null) {157          printedWithType += `\n\nTo provide a hint without properties: toMatchSnapshot('hint')`;158        }159      }160      throw new Error(161        (0, _jestMatcherUtils.matcherErrorMessage)(162          (0, _jestMatcherUtils.matcherHint)(163            matcherName,164            undefined,165            _printSnapshot.PROPERTIES_ARG,166            options167          ),168          `Expected ${(0, _jestMatcherUtils.EXPECTED_COLOR)(169            'properties'170          )} must be an object`,171          printedWithType172        )173      );174    } // Future breaking change: Snapshot hint must be a string175    // if (arguments.length === 3 && typeof hint !== 'string') {}176    properties = propertiesOrHint;177  }178  return _toMatchSnapshot({179    context: this,180    hint,181    isInline: false,182    matcherName,183    properties,184    received185  });186};187const toMatchInlineSnapshot = function (188  received,189  propertiesOrSnapshot,190  inlineSnapshot191) {192  const matcherName = 'toMatchInlineSnapshot';193  let properties;194  const length = arguments.length;195  if (length === 2 && typeof propertiesOrSnapshot === 'string') {196    inlineSnapshot = propertiesOrSnapshot;197  } else if (length >= 2) {198    const options = {199      isNot: this.isNot,200      promise: this.promise201    };202    if (length === 3) {203      options.secondArgument = _printSnapshot.SNAPSHOT_ARG;204      options.secondArgumentColor = _printSnapshot.noColor;205    }206    if (207      typeof propertiesOrSnapshot !== 'object' ||208      propertiesOrSnapshot === null209    ) {210      throw new Error(211        (0, _jestMatcherUtils.matcherErrorMessage)(212          (0, _jestMatcherUtils.matcherHint)(213            matcherName,214            undefined,215            _printSnapshot.PROPERTIES_ARG,216            options217          ),218          `Expected ${(0, _jestMatcherUtils.EXPECTED_COLOR)(219            'properties'220          )} must be an object`,221          (0, _jestMatcherUtils.printWithType)(222            'Expected properties',223            propertiesOrSnapshot,224            _printSnapshot.printExpected225          )226        )227      );228    }229    if (length === 3 && typeof inlineSnapshot !== 'string') {230      throw new Error(231        (0, _jestMatcherUtils.matcherErrorMessage)(232          (0, _jestMatcherUtils.matcherHint)(233            matcherName,234            undefined,235            _printSnapshot.PROPERTIES_ARG,236            options237          ),238          `Inline snapshot must be a string`,239          (0, _jestMatcherUtils.printWithType)(240            'Inline snapshot',241            inlineSnapshot,242            utils.serialize243          )244        )245      );246    }247    properties = propertiesOrSnapshot;248  }249  return _toMatchSnapshot({250    context: this,251    inlineSnapshot:252      inlineSnapshot !== undefined253        ? stripAddedIndentation(inlineSnapshot)254        : undefined,255    isInline: true,256    matcherName,257    properties,258    received259  });260};261const _toMatchSnapshot = config => {262  const {263    context,264    hint,265    inlineSnapshot,266    isInline,267    matcherName,268    properties269  } = config;270  let {received} = config;271  context.dontThrow && context.dontThrow();272  const {currentTestName, isNot, snapshotState} = context;273  if (isNot) {274    throw new Error(275      (0, _jestMatcherUtils.matcherErrorMessage)(276        (0, _printSnapshot.matcherHintFromConfig)(config, false),277        NOT_SNAPSHOT_MATCHERS278      )279    );280  }281  if (snapshotState == null) {282    // Because the state is the problem, this is not a matcher error.283    // Call generic stringify from jest-matcher-utils package284    // because uninitialized snapshot state does not need snapshot serializers.285    throw new Error(286      (0, _printSnapshot.matcherHintFromConfig)(config, false) +287        '\n\n' +288        `Snapshot state must be initialized` +289        '\n\n' +290        (0, _jestMatcherUtils.printWithType)(291          'Snapshot state',292          snapshotState,293          _jestMatcherUtils.stringify294        )295    );296  }297  const fullTestName =298    currentTestName && hint299      ? `${currentTestName}: ${hint}`300      : currentTestName || ''; // future BREAKING change: || hint301  if (typeof properties === 'object') {302    if (typeof received !== 'object' || received === null) {303      throw new Error(304        (0, _jestMatcherUtils.matcherErrorMessage)(305          (0, _printSnapshot.matcherHintFromConfig)(config, false),306          `${(0, _jestMatcherUtils.RECEIVED_COLOR)(307            'received'308          )} value must be an object when the matcher has ${(0,309          _jestMatcherUtils.EXPECTED_COLOR)('properties')}`,310          (0, _jestMatcherUtils.printWithType)(311            'Received',312            received,313            _printSnapshot.printReceived314          )315        )316      );317    }318    const propertyPass = context.equals(received, properties, [319      context.utils.iterableEquality,320      context.utils.subsetEquality321    ]);322    if (!propertyPass) {323      const key = snapshotState.fail(fullTestName, received);324      const matched = /(\d+)$/.exec(key);325      const count = matched === null ? 1 : Number(matched[1]);326      const message = () =>327        (0, _printSnapshot.matcherHintFromConfig)(config, false) +328        '\n\n' +329        printSnapshotName(currentTestName, hint, count) +330        '\n\n' +331        (0, _printSnapshot.printPropertiesAndReceived)(332          properties,333          received,334          snapshotState.expand335        );336      return {337        message,338        name: matcherName,339        pass: false340      };341    } else {342      received = utils.deepMerge(received, properties);343    }344  }345  const result = snapshotState.match({346    error: context.error,347    inlineSnapshot,348    isInline,349    received,350    testName: fullTestName351  });352  const {actual, count, expected, pass} = result;353  if (pass) {354    return {355      message: () => '',356      pass: true357    };358  }359  const message =360    expected === undefined361      ? () =>362          (0, _printSnapshot.matcherHintFromConfig)(config, true) +363          '\n\n' +364          printSnapshotName(currentTestName, hint, count) +365          '\n\n' +366          `New snapshot was ${(0, _jestMatcherUtils.BOLD_WEIGHT)(367            'not written'368          )}. The update flag ` +369          `must be explicitly passed to write a new snapshot.\n\n` +370          `This is likely because this test is run in a continuous integration ` +371          `(CI) environment in which snapshots are not written by default.\n\n` +372          `Received:${actual.includes('\n') ? '\n' : ' '}${(0,373          _printSnapshot.bReceivedColor)(actual)}`374      : () =>375          (0, _printSnapshot.matcherHintFromConfig)(config, true) +376          '\n\n' +377          printSnapshotName(currentTestName, hint, count) +378          '\n\n' +379          (0, _printSnapshot.printSnapshotAndReceived)(380            expected,381            actual,382            received,383            snapshotState.expand384          ); // Passing the actual and expected objects so that a custom reporter385  // could access them, for example in order to display a custom visual diff,386  // or create a different error message387  return {388    actual,389    expected,390    message,391    name: matcherName,392    pass: false393  };394};395const toThrowErrorMatchingSnapshot = function (396  received,397  hint, // because error TS1016 for hint?: string398  fromPromise399) {400  const matcherName = 'toThrowErrorMatchingSnapshot'; // Future breaking change: Snapshot hint must be a string401  // if (hint !== undefined && typeof hint !== string) {}402  return _toThrowErrorMatchingSnapshot(403    {404      context: this,405      hint,406      isInline: false,407      matcherName,408      received409    },410    fromPromise411  );412};413const toThrowErrorMatchingInlineSnapshot = function (414  received,415  inlineSnapshot,416  fromPromise417) {418  const matcherName = 'toThrowErrorMatchingInlineSnapshot';419  if (inlineSnapshot !== undefined && typeof inlineSnapshot !== 'string') {420    const options = {421      expectedColor: _printSnapshot.noColor,422      isNot: this.isNot,423      promise: this.promise424    };425    throw new Error(426      (0, _jestMatcherUtils.matcherErrorMessage)(427        (0, _jestMatcherUtils.matcherHint)(428          matcherName,429          undefined,430          _printSnapshot.SNAPSHOT_ARG,431          options432        ),433        `Inline snapshot must be a string`,434        (0, _jestMatcherUtils.printWithType)(435          'Inline snapshot',436          inlineSnapshot,437          utils.serialize438        )439      )440    );441  }442  return _toThrowErrorMatchingSnapshot(443    {444      context: this,445      inlineSnapshot:446        inlineSnapshot !== undefined447          ? stripAddedIndentation(inlineSnapshot)448          : undefined,449      isInline: true,450      matcherName,451      received452    },453    fromPromise454  );455};456const _toThrowErrorMatchingSnapshot = (config, fromPromise) => {457  const {458    context,459    hint,460    inlineSnapshot,461    isInline,...

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