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How to use toCustomMatch method in Jest

Best JavaScript code snippet using jest

stacktrace.test.js

Source:stacktrace.test.js

...6 *7 */8const jestExpect = require('../');9jestExpect.extend({10  toCustomMatch(callback, expectation) {11    const actual = callback();12    if (actual !== expectation) {13      return {14        message: () => `Expected "${expectation}" but got "${actual}"`,15        pass: false,16      };17    }18    return {pass: true};19  },20  toMatchPredicate(received, argument) {21    argument(received);22    return {23      message: () => '',24      pass: true,25    };26  },27});28it('stack trace points to correct location when using matchers', () => {29  try {30    jestExpect(true).toBe(false);31  } catch (error) {32    expect(error.stack).toContain('stacktrace.test.js:35');33  }34});35it('stack trace points to correct location when using nested matchers', () => {36  try {37    jestExpect(true).toMatchPredicate(value => {38      jestExpect(value).toBe(false);39    });40  } catch (error) {41    expect(error.stack).toContain('stacktrace.test.js:44');42  }43});44it('stack trace points to correct location when throwing from a custom matcher', () => {45  try {46    jestExpect(() => {47      const foo = () => bar();48      const bar = () => baz();49      const baz = () => {50        throw new Error('Expected');51      };52      foo();53    }).toCustomMatch('bar');54  } catch (error) {55    expect(error.stack).toContain('stacktrace.test.js:57');56  }...

93stacktrace.test.js

Source:93stacktrace.test.js

...6 *7 */8const jestExpect = require('../');9jestExpect.extend({10  toCustomMatch(callback, expectation) {11    const actual = callback();12    if (actual !== expectation) {13      return {14        message: () => `Expected "${expectation}" but got "${actual}"`,15        pass: false,16      };17    }18    return {pass: true};19  },20  toMatchPredicate(received, argument) {21    argument(received);22    return {23      message: () => '',24      pass: true,25    };26  },27});28it('stack trace points to correct location when using matchers', () => {29  try {30    jestExpect(true).toBe(false);31  } catch (error) {32    expect(error.stack).toContain('stacktrace.test.js:35');33  }34});35it('stack trace points to correct location when using nested matchers', () => {36  try {37    jestExpect(true).toMatchPredicate(value => {38      jestExpect(value).toBe(false);39    });40  } catch (error) {41    expect(error.stack).toContain('stacktrace.test.js:44');42  }43});44it('stack trace points to correct location when throwing from a custom matcher', () => {45  try {46    jestExpect(() => {47      const foo = () => bar();48      const bar = () => baz();49      const baz = () => {50        throw new Error('Expected');51      };52      foo();53    }).toCustomMatch('bar');54  } catch (error) {55    expect(error.stack).toContain('stacktrace.test.js:57');56  }...

sync.test.js

Source:sync.test.js

...5 * LICENSE file in the root directory of this source tree.6 *7 */8'use strict';9function toCustomMatch(callback, expectation) {10  const actual = callback();11  if (actual !== expectation) {12    return {13      message: () => `Expected "${expectation}" but got "${actual}"`,14      pass: false,15    };16  } else {17    return {pass: true};18  }19}20expect.extend({21  toCustomMatch,22});23describe('Custom matcher', () => {24  it('passes', () => {25    // This expectation should pass26    expect(() => 'foo').toCustomMatch('foo');27  });28  it('fails', () => {29    expect(() => {30      // This expectation should fail,31      // Which is why it's wrapped in a .toThrow() block.32      expect(() => 'foo').toCustomMatch('bar');33    }).toThrow();34  });35  it('preserves error stack', () => {36    const foo = () => bar();37    const bar = () => baz();38    const baz = () => {39      throw Error('qux');40    };41    // This expecation fails due to an error we throw (intentionally)42    // The stack trace should point to the line that throws the error though,43    // Not to the line that calls the matcher.44    expect(() => {45      foo();46    }).toCustomMatch('test');47  });...

customMatcher.test.js

Source:customMatcher.test.js

...5 * LICENSE file in the root directory of this source tree.6 *7 */8'use strict';9function toCustomMatch(callback, expectation) {10  const actual = callback();11  if (actual !== expectation) {12    return {13      message: () => `Expected "${expectation}" but got "${actual}"`,14      pass: false,15    };16  } else {17    return {pass: true};18  }19}20expect.extend({21  toCustomMatch,22});23describe('Custom matcher', () => {24  it('passes', () => {25    // This expectation should pass26    expect(() => 'foo').toCustomMatch('foo');27  });28  it('fails', () => {29    expect(() => {30      // This expectation should fail,31      // Which is why it's wrapped in a .toThrow() block.32      expect(() => 'foo').toCustomMatch('bar');33    }).toThrow();34  });35  it('preserves error stack', () => {36    const foo = () => bar();37    const bar = () => baz();38    const baz = () => {39      throw Error('qux');40    };41    // This expecation fails due to an error we throw (intentionally)42    // The stack trace should point to the line that throws the error though,43    // Not to the line that calls the matcher.44    expect(() => {45      foo();46    }).toCustomMatch('test');47  });...

custom_matcher.test.js

Source:custom_matcher.test.js

...5 * LICENSE file in the root directory of this source tree.6 *7 */8'use strict';9function toCustomMatch(callback, expectation) {10  const actual = callback();11  if (actual !== expectation) {12    return {13      message: () => `Expected "${expectation}" but got "${actual}"`,14      pass: false,15    };16  } else {17    return {pass: true};18  }19}20expect.extend({21  toCustomMatch,22});23describe('Custom matcher', () => {24  it('passes', () => {25    // This expectation should pass26    expect(() => 'foo').toCustomMatch('foo');27  });28  it('fails', () => {29    expect(() => {30      // This expectation should fail,31      // Which is why it's wrapped in a .toThrow() block.32      expect(() => 'foo').toCustomMatch('bar');33    }).toThrow();34  });35  it('preserves error stack', () => {36    const foo = () => bar();37    const bar = () => baz();38    const baz = () => {39      throw Error('qux');40    };41    // This expecation fails due to an error we throw (intentionally)42    // The stack trace should point to the line that throws the error though,43    // Not to the line that calls the matcher.44    expect(() => {45      foo();46    }).toCustomMatch('test');47  });...

50custom_matcher.test.js

Source:50custom_matcher.test.js

...5 * LICENSE file in the root directory of this source tree.6 *7 */8'use strict';9function toCustomMatch(callback, expectation) {10  const actual = callback();11  if (actual !== expectation) {12    return {13      message: () => `Expected "${expectation}" but got "${actual}"`,14      pass: false,15    };16  } else {17    return {pass: true};18  }19}20expect.extend({21  toCustomMatch,22});23describe('Custom matcher', () => {24  it('passes', () => {25    // This expectation should pass26    expect(() => 'foo').toCustomMatch('foo');27  });28  it('fails', () => {29    expect(() => {30      // This expectation should fail,31      // Which is why it's wrapped in a .toThrow() block.32      expect(() => 'foo').toCustomMatch('bar');33    }).toThrow();34  });35  it('preserves error stack', () => {36    const foo = () => bar();37    const bar = () => baz();38    const baz = () => {39      throw Error('qux');40    };41    // This expecation fails due to an error we throw (intentionally)42    // The stack trace should point to the line that throws the error though,43    // Not to the line that calls the matcher.44    expect(() => {45      foo();46    }).toCustomMatch('test');47  });...

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