How to use fnNameFor method in Jest

Best JavaScript code snippet using jest

toThrowError.js

Source:toThrowError.js

...25        if (!(thrown instanceof Error)) {26          return fail("Expected function to throw an Error, but it threw " + thrown + ".");27        }28        if (arguments.length == 1) {29          return pass("Expected function not to throw an Error, but it threw " + fnNameFor(thrown) + ".");30        }31        if (errorType) {32          name = fnNameFor(errorType);33          constructorName = fnNameFor(thrown.constructor);34        }35        if (errorType && message) {36          if (thrown.constructor == errorType && util.equals(thrown.message, message)) {37            return pass("Expected function not to throw " + name + " with message \"" + message + "\".");38          } else {39            return fail("Expected function to throw " + name + " with message \"" + message +40                        "\", but it threw " + constructorName + " with message \"" + thrown.message + "\".");41          }42        }43        if (errorType && regexp) {44          if (thrown.constructor == errorType && regexp.test(thrown.message)) {45            return pass("Expected function not to throw " + name + " with message matching " + regexp + ".");46          } else {47            return fail("Expected function to throw " + name + " with message matching " + regexp +48                        ", but it threw " + constructorName + " with message \"" + thrown.message + "\".");49          }50        }51        if (errorType) {52          if (thrown.constructor == errorType) {53            return pass("Expected function not to throw " + name + ".");54          } else {55            return fail("Expected function to throw " + name + ", but it threw " + constructorName + ".");56          }57        }58        if (message) {59          if (thrown.message == message) {60            return pass("Expected function not to throw an exception with message " + j$.pp(message) + ".");61          } else {62            return fail("Expected function to throw an exception with message " + j$.pp(message) +63                        ", but it threw an exception with message " + j$.pp(thrown.message) + ".");64          }65        }66        if (regexp) {67          if (regexp.test(thrown.message)) {68            return pass("Expected function not to throw an exception with a message matching " + j$.pp(regexp) + ".");69          } else {70            return fail("Expected function to throw an exception with a message matching " + j$.pp(regexp) +71                        ", but it threw an exception with message " + j$.pp(thrown.message) + ".");72          }73        }74        function fnNameFor(func) {75            return func.name || func.toString().match(/^\s*function\s*(\w*)\s*\(/)[1];76        }77        function pass(notMessage) {78          return {79            pass: true,80            message: notMessage81          };82        }83        function fail(message) {84          return {85            pass: false,86            message: message87          };88        }...

asymmetric-matchers.js

Source:asymmetric-matchers.js

...58    }59    if (this.sample == Boolean) {60      return 'boolean';61    }62    return fnNameFor(this.sample);63  }64  toAsymmetricMatcher() {65    return 'Any<' + fnNameFor(this.sample) + '>';66  }}67class Anything extends AsymmetricMatcher {68  asymmetricMatch(other) {69    return !isUndefined(other) && other !== null;70  }71  toString() {72    return 'Anything';73  }74  // No getExpectedType method, because it matches either null or undefined.75  toAsymmetricMatcher() {76    return 'Anything';77  }}78class ArrayContaining extends AsymmetricMatcher {79  constructor(sample) {...

AsymmetricMatcher-test.js

Source:AsymmetricMatcher-test.js

...9'use strict';10const prettyFormat = require('../');11const AsymmetricMatcher = require('../plugins/AsymmetricMatcher');12let options;13function fnNameFor(func) {14  if (func.name) {15    return func.name;16  }17  const matches = func.toString().match(/^\s*function\s*(\w*)\s*\(/);18  return matches ? matches[1] : '<anonymous>';19}20beforeEach(() => {21  options = {plugins: [AsymmetricMatcher]};22});23[24  String,25  Function,26  Array,27  Object,28  RegExp,29  Symbol,30  Function,31  () => {},32  function namedFuntction() {},33].forEach(type => {34  test(`supports any(${fnNameFor(type)})`, () => {35    const result = prettyFormat(expect.any(type), options);36    expect(result).toEqual(`Any<${fnNameFor(type)}>`);37  });38  test(`supports nested any(${fnNameFor(type)})`, () => {39    const result = prettyFormat(40      {41        test: {42          nested: expect.any(type),43        },44      },45      options,46    );47    expect(result).toEqual(48      `Object {\n  "test": Object {\n    "nested": Any<${fnNameFor(type)}>,\n  },\n}`,49    );50  });51});52test(`anything()`, () => {53  const result = prettyFormat(expect.anything(), options);54  expect(result).toEqual('Anything');55});56test(`arrayContaining()`, () => {57  const result = prettyFormat(expect.arrayContaining([1, 2]), options);58  expect(result).toEqual(59    `ArrayContaining [60  1,61  2,62]`,...

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|it('check_object_of_Car', () => { expect(newCar()).toBeInstanceOf(Car); });| | :- |

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