Best JavaScript code snippet using fast-check-monorepo
createErrorRecord.spec.js
Source:createErrorRecord.spec.js
1import errorRecord from '../createErrorRecord';2jest.spyOn(console, 'error');3const fakeSeconds = jest.fn();4const fakeRandom = jest.fn();5const fakeWindow = {6 location: window.location,7 Date: class {8 getSeconds() {9 return fakeSeconds();10 }11 },12 Math: {13 random: fakeRandom14 }15};16beforeEach(() => {17 console.error.mockClear();18 fakeSeconds.mockClear();19 fakeRandom.mockClear();20});21afterAll(() => {22 console.error.mockRestore();23});24const firstError = new Error('test');25test('creates a record from an error', () => {26 fakeSeconds.mockReturnValueOnce(30);27 fakeRandom.mockReturnValueOnce(0.456);28 const record = errorRecord(firstError, fakeWindow);29 expect(record).toMatchObject({30 error: firstError,31 id: 'Error30G',32 loc: expect.stringMatching(/^at /)33 });34});35test('caches already seen errors', () => {36 const record = errorRecord(firstError, fakeWindow);37 expect(record).toMatchObject({38 error: firstError,39 id: 'Error30G',40 loc: expect.stringMatching(/^at /)41 });42 expect(fakeSeconds).not.toHaveBeenCalled();43});44test('makes IDs from error names or constructor names', () => {45 fakeSeconds.mockReturnValue(1);46 fakeRandom.mockReturnValue(0.1);47 class CustomError extends Error {}48 expect(errorRecord(new CustomError('bluh'), fakeWindow)).toMatchObject({49 id: 'CustomError13'50 });51 Object.defineProperty(CustomError, 'name', {52 value: 'CustomNameOverride'53 });54 expect(errorRecord(new CustomError('blar'), fakeWindow)).toMatchObject({55 id: 'CustomNameOverride13'56 });57 Object.defineProperty(CustomError, 'name', {58 value: undefined59 });60 const errorWithName = new CustomError('ack');61 Object.defineProperty(errorWithName, 'name', {62 value: 'ACK'63 });64 expect(errorRecord(errorWithName, fakeWindow)).toMatchObject({65 id: 'ACK13'66 });67 const errorWithNoConstructor = new Error('ack');68 Object.defineProperties(errorWithNoConstructor, {69 constructor: {70 value: undefined71 },72 name: {73 value: 'woah'74 }75 });76 expect(errorRecord(errorWithNoConstructor, fakeWindow)).toMatchObject({77 id: 'woah13'78 });79});80test('uses custom stacks', () => {81 fakeSeconds.mockReturnValue(1);82 fakeRandom.mockReturnValue(0.1);83 expect(84 errorRecord(85 new Error('guh'),86 fakeWindow,87 {},88 'Error: guh\n at a custom stack'89 )90 ).toMatchObject({91 loc: 'at a custom stack'92 });93});94test('loc is empty if stack cannot be parsed', () => {95 fakeSeconds.mockReturnValue(1);96 fakeRandom.mockReturnValue(0.1);97 expect(98 errorRecord(new Error('guh'), fakeWindow, {}, 'an unrecognizable stack')99 ).toMatchObject({100 loc: ''101 });...
simpleVirus.test.ts
Source:simpleVirus.test.ts
1import { createSimpleVirus, createSimpleVirusPopulation } from './simpleVirus';2describe('createSimpleVirus', () => {3 it('returns the birthProb and clearProb args as properties', () => {4 const { birthProb, clearProb } = createSimpleVirus({5 birthProb: 0.3,6 clearProb: 0.5,7 random0to1: Math.random,8 });9 expect(birthProb).toEqual(0.3);10 expect(clearProb).toEqual(0.5);11 });12 it('returns a method doesSurvive that returns true when random is bigger than clearProb', () => {13 const fakeRandom = () => 0.4;14 const virus = createSimpleVirus({15 birthProb: 0.3,16 clearProb: 0.3,17 random0to1: fakeRandom,18 });19 expect(virus.doesSurvive()).toEqual(true);20 });21 it('returns a method doesSurvive that returns false when random is smaller than clearProb', () => {22 const fakeRandom = () => 0.2;23 const virus = createSimpleVirus({24 birthProb: 0.3,25 clearProb: 0.3,26 random0to1: fakeRandom,27 });28 expect(virus.doesSurvive()).toEqual(false);29 });30 it('returns a method doesReproduce that returns true when random is smaller than birthProb * (1 - popDensity)', () => {31 const fakeRandom = () => 0.4;32 const virus = createSimpleVirus({33 birthProb: 1,34 clearProb: 0.3,35 random0to1: fakeRandom,36 });37 // random 0.4 < birthProb 1 * (1 - 0.5) // true38 expect(virus.doesReproduce(0.5)).toEqual(true);39 });40 it('returns a method doesReproduce that returns false when random is larger than birthProb * (1 - popDensity)', () => {41 const fakeRandom = () => 0.6;42 const virus = createSimpleVirus({43 birthProb: 1,44 clearProb: 0.3,45 random0to1: fakeRandom,46 });47 // random 0.6 < birthProb 1 * (1 - 0.5) // false48 expect(virus.doesReproduce(0.5)).toEqual(false);49 });50});51describe('createVirusPopulation', () => {52 it('returns an array of the specified length', () => {53 const viruses = createSimpleVirusPopulation({54 virusCount: 13,55 birthProb: 0.1,56 clearProb: 0.01,57 });58 expect(viruses.length).toEqual(13);59 });...
jest.setup.after.js
Source:jest.setup.after.js
1let fakeRandom = 0;2beforeEach(() => {3 jest.spyOn(global.Math, 'random').mockImplementation(() => {4 fakeRandom += 0.00001;5 return fakeRandom;6 });7});8afterEach(() => {9 fakeRandom = 0;10 jest.spyOn(global.Math, 'random').mockRestore();...
Using AI Code Generation
1import * as fc from "fast-check";2import { fakeRandom } from "fast-check-monorepo";3describe("test3", () => {4 it("test3", () => {5 fc.assert(6 fc.property(fc.integer(), fc.integer(), (a, b) => {7 const random = fakeRandom([a, b]);8 return random() === a && random() === b;9 })10 );11 });12});13import * as fc from "fast-check";14import { fakeRandom } from "fast-check-monorepo";15describe("test3", () => {16 it("test3", () => {17 fc.assert(18 fc.property(fc.integer(), fc.integer(), (a, b) => {19 const random = fakeRandom([a, b]);20 return random() === a;21 })22 );23 });24});25I have a simple test that uses fakeRandom to test a function that uses Math.random() to generate random numbers. The test passes when I use the following code:26import * as fc from "fast-check";27import { fakeRandom } from "fast-check-monorepo";28describe("test1", () => {29 it("test1", () => {30 fc.assert(31 fc.property(fc.integer(), fc.integer(), (a, b) => {32 const random = fakeRandom([a, b]);33 return random() === a;34 })35 );36 });37});38import * as fc from "fast-check";39import { fakeRandom } from "fast-check-monorepo";40describe("test2", () => {41 it("test2", () => {42 fc.assert(43 fc.property(fc.integer(), fc.integer(), (a, b) => {44 const random = fakeRandom([a, b]);45 return random() === a && random() === b;46 })47 );48 });49});
Using AI Code Generation
1const { fakeRandom } = require('fast-check-monorepo');2const { integer } = require('fast-check-monorepo/lib/arbitrary/IntegerArbitrary.js');3const { property } = require('fast-check-monorepo/lib/check/property/Property.js');4property(5 integer(),6 integer(),7 (a, b) => {8 const random = fakeRandom([a, b]);9 return random.nextInt(0, 1) === a;10 }11).check();12 at Object.nextInt (C:\Users\mike\Documents\test3\node_modules\fast-check-monorepo\lib\random\Random.js:32:31)13 at Property.<anonymous> (C:\Users\mike\Documents\test3\test3.js:10:26)14 at Property._execute (C:\Users\mike\Documents\test3\node_modules\fast-check-monorepo\lib\check\property\Property.js:113:19)15 at Property.check (C:\Users\mike\Documents\test3\node_modules\fast-check-monorepo\lib\check\property\Property.js:69:19)16 at Object.<anonymous> (C:\Users\mike\Documents\test3\test3.js:13:9)17 at Module._compile (internal/modules/cjs/loader.js:1137:30)18 at Object.Module._extensions..js (internal/modules/cjs/loader.js:1157:10)19 at Module.load (internal/modules/cjs/loader.js:985:32)20 at Function.Module._load (internal/modules/cjs/loader.js:878:14)21 at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)22So in your case you should install fast-check instead of fast-check-monorepo and import the different packages from
Using AI Code Generation
1const fc = require("fast-check");2const { fakeRandom } = require("fast-check-monorepo");3let random = fakeRandom([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 0);4fc.assert(5 fc.property(fc.integer(), (n) => {6 return n === random.nextInt(0, 10);7 })8);9const fc = require("fast-check");10const { fakeRandom } = require("fast-check-monorepo");11let random = fakeRandom([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 0);12fc.assert(13 fc.property(fc.integer(), (n) => {14 return n === random.nextInt(0, 10);15 })16);
Using AI Code Generation
1const fc = require('fast-check');2const { fakeRandom } = require('fast-check-monorepo');3const { fakeRandom } = require('fast-check');4const fc = require('fast-check');5fc.assert(6 fc.property(fc.integer(), fc.integer(), (a, b) => {7 const r = fakeRandom();8 const r = fakeRandom();9 return a + b === b + a;10 })11);
Using AI Code Generation
1import { fakeRandom } from "fast-check-monorepo";2describe("test3", () => {3 it("should work", () => {4 const rand = fakeRandom();5 const result = rand.nextInt(1, 10);6 expect(result).toBe(2);7 });8});9I have a function that takes a string as an argument and returns an array of strings. I want to write a test that checks that the function returns an array of strings. I have tried using expect.any(Array) and expect.arrayContaining() but I am getting the following error when running the test:10I have tried using expect.any(Array) and expect.arrayContaining() but I am getting the following error when running the test:11I am trying to write a test for a function that takes a string as an argument and returns an array of strings. I want to write a test that checks that the function returns an array of strings. I have tried using expect.any(Array) and expect.arrayContaining() but I am getting the following error when running the test:12I am trying to write a test for a function that takes a string as an argument and returns an array of strings. I want to write a test that checks that the function returns an array of strings. I have tried using expect.any(Array) and expect.arrayContaining() but I am getting the following error when running the test:
Using AI Code Generation
1const { fakeRandom } = require('fast-check');2const generateRandomNumber = (min, max) => {3 const random = fakeRandom();4 return random.nextInt(min, max);5};6module.exports = {7};8const { fakeRandom } = require('fast-check');9const generateRandomNumber = (min, max) => {10 const random = fakeRandom();11 return random.nextInt(min, max);12};13module.exports = {14};15const { fakeRandom } = require('fast-check');16const generateRandomNumber = (min, max) => {17 const random = fakeRandom();18 return random.nextInt(min, max);19};20module.exports = {21};22const { fakeRandom } = require('fast-check');23const generateRandomNumber = (min, max) => {24 const random = fakeRandom();25 return random.nextInt(min, max);26};27module.exports = {28};29const { fakeRandom } = require('fast-check');30const generateRandomNumber = (min, max) => {31 const random = fakeRandom();32 return random.nextInt(min, max);33};34module.exports = {35};36const { fakeRandom } = require('fast-check');37const generateRandomNumber = (min, max) => {38 const random = fakeRandom();39 return random.nextInt(min, max);40};41module.exports = {42};
Using AI Code Generation
1const fc = require('fast-check-monorepo');2const { fakeRandom } = fc;3const { myMethod } = require('my-module');4describe('myMethod', () => {5 it('should always return 42', () => {6 fc.assert(7 fc.property(fc.integer(), seed => {8 const rng = fakeRandom(seed);9 const result = myMethod(rng);10 return result === 42;11 })12 );13 });14});15const fc = require('fast-check-monorepo');16const { fakeRandom } = fc;17const { myMethod } = require('my-module');18describe('myMethod', () => {19 it('should always return 42', () => {20 fc.assert(21 fc.property(fc.integer(), fc.integer(), (seed, input) => {22 const rng = fakeRandom(seed);23 const result = myMethod(rng, input);24 return result === 42;25 })26 );27 });28});
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