How to use jest-message-util - 10 common examples

const printActualErrorMessage = error => {
    if (error) {
        const {message, stack} = separateMessageFromStack(error.stack);
        return (
            'Instead, it threw:\n' +
            /* eslint-disable-next-line new-cap */
            RECEIVED_COLOR(
                `  ${message}` +
                formatStackTrace(
                    // remove KaTeX internal stack entries
                    stack.split('\n')
                        .filter(line => line.indexOf('new ParseError') === -1)
                        .join('\n'),
                    {
                        rootDir: process.cwd(),
                        testMatch: [],
                    },
                    {
                        noStackTrace: false,

const printActualErrorMessage = error => {
    if (error) {
        const {message, stack} = separateMessageFromStack(error.stack);
        return (
            'Instead, it threw:\n' +
            /* eslint-disable-next-line new-cap */
            RECEIVED_COLOR(
                `  ${message}` +
                formatStackTrace(
                    // remove KaTeX internal stack entries
                    stack.split('\n')
                        .filter(line => line.indexOf('new ParseError') === -1)
                        .join('\n'),
                    {
                        rootDir: process.cwd(),
                        testMatch: [],
                    },
                    {
                        noStackTrace: false,
                    },
                ),
            )
        );
    }
    return 'But it didn\'t throw anything.';

const formatError = (error: string | ErrorWithCode): SerializableError => {
  if (typeof error === 'string') {
    const {message, stack} = separateMessageFromStack(error);
    return {
      message,
      stack,
      type: 'Error',
    };
  }

  return {
    code: error.code || undefined,
    message: error.message,
    stack: error.stack,
    type: 'Error',
  };
};

console.log(
      formatExecError(
        new ErrorWithStack(
          chalk.yellow(
            'Returning a Promise from "describe" is not supported. Tests must be defined synchronously.\n' +
              'Returning a value from "describe" will fail the test in a future version of Jest.',
          ),
          describeFn,
        ),
        {rootDir: '', testMatch: []},
        {noStackTrace: false},
      ),
    );
  } else if (describeReturn !== undefined) {
    console.log(
      formatExecError(
        new ErrorWithStack(
          chalk.yellow(
            'A "describe" callback must not return a value.\n' +
              'Returning a value from "describe" will fail the test in a future version of Jest.',
          ),
          describeFn,
        ),
        {rootDir: '', testMatch: []},
        {noStackTrace: false},
      ),
    );
  }

  dispatch({blockName, mode, name: 'finish_describe_definition'});
};

export const buildFailureTestResult = (
  testPath: string,
  err: Error,
  config: ProjectConfig,
  globalConfig: GlobalConfig,
): TestResult => {
  const failureMessage = formatExecError(err, config, globalConfig);
  return {
    console: null,
    displayName: '',
    failureMessage,
    leaks: false,
    numFailingTests: 0,
    numPassingTests: 0,
    numPendingTests: 0,
    perfStats: {
      end: 0,
      start: 0,
    },
    skipped: false,
    snapshot: {
      added: 0,
      fileDeleted: false,

export const buildFailureTestResult = (
  testPath: string,
  err: Error,
  config: ProjectConfig,
  globalConfig: GlobalConfig,
): TestResult => {
  const failureMessage = formatExecError(err, config, globalConfig);
  return {
    console: null,
    displayName: '',
    failureMessage,
    leaks: false,
    numFailingTests: 0,
    numPassingTests: 0,
    numPendingTests: 0,
    perfStats: {
      end: 0,
      start: 0,
    },
    skipped: false,
    snapshot: {
      added: 0,
      fileDeleted: false,

        .map(err => formatExecError(err, config, globalConfig))
        .join('\n');

Error.prepareStackTrace = (error, trace) => {
    const prepared = prepareStackTrace
      ? separateMessageFromStack(prepareStackTrace(error, trace))
      : error;
    const transformed = transform ? transform(prepared) : prepared;
    return pretty(transformed);
  };
}

testResults.forEach(testResult => {
      if (testResult.status === 'failed') {
        numFailingTests++;
      } else if (testResult.status === 'pending') {
        numPendingTests++;
      } else if (testResult.status === 'todo') {
        numTodoTests++;
      } else {
        numPassingTests++;
      }
    });

    const testResult = {
      ...createEmptyTestResult(),
      console: null,
      failureMessage: formatResultsErrors(
        testResults,
        this._config,
        this._globalConfig,
        this._testPath,
      ),
      numFailingTests,
      numPassingTests,
      numPendingTests,
      numTodoTests,
      snapshot: {
        added: 0,
        fileDeleted: false,
        matched: 0,
        unchecked: 0,
        unmatched: 0,
        updated: 0,

ancestorTitles,
        duration: testResult.duration,
        failureMessages: testResult.errors,
        fullName: title
          ? ancestorTitles.concat(title).join(' ')
          : ancestorTitles.join(' '),
        invocations: testResult.invocations,
        location: testResult.location,
        numPassingAsserts: 0,
        status,
        title: testResult.testPath[testResult.testPath.length - 1],
      };
    },
  );

  let failureMessage = formatResultsErrors(
    assertionResults,
    config,
    globalConfig,
    testPath,
  );
  let testExecError;

  if (runResult.unhandledErrors.length) {
    testExecError = {
      message: '',
      stack: runResult.unhandledErrors.join('\n'),
    };
    failureMessage =
      (failureMessage || '') +
      '\n\n' +
      runResult.unhandledErrors