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How to use ConstantArbitrary method in fast-check-monorepo

Best JavaScript code snippet using fast-check-monorepo

ConstantArbitrary.spec.ts

Source:ConstantArbitrary.spec.ts

...16      const expectedBiasFactor = 48;17      const value = Symbol();18      const { instance: mrng } = fakeRandom();19      // Act20      const arb = new ConstantArbitrary([value]);21      const g = arb.generate(mrng, expectedBiasFactor);22      // Assert23      expect(g.value).toEqual(value);24      expect(g.hasToBeCloned).toBe(false);25    });26    it('should call Random to generate any integer in [0, length-1] when provided multiple values', () =>27      fc.assert(28        fc.property(29          fc.array(fc.anything(), { minLength: 2 }),30          fc.option(fc.integer({ min: 2 }), { nil: undefined }),31          fc.nat(),32          (values, biasFactor, mod) => {33            // Arrange34            const { instance: mrng, nextInt } = fakeRandom();35            nextInt.mockImplementation((a, b) => a + (mod % (b - a + 1)));36            // Act37            const arb = new ConstantArbitrary(values);38            const g = arb.generate(mrng, biasFactor);39            // Assert40            expect(nextInt).toHaveBeenCalledTimes(1);41            expect(nextInt).toHaveBeenCalledWith(0, values.length - 1);42            expect(values).toContainEqual(g.value);43          }44        )45      ));46    it('should be able to generate any of the requested values', () =>47      fc.assert(48        fc.property(49          fc.array(fc.anything(), { minLength: 2 }),50          fc.option(fc.integer({ min: 2 }), { nil: undefined }),51          (values, biasFactor) => {52            // Arrange53            const { instance: mrng, nextInt } = fakeRandom();54            // Act / Assert55            const arb = new ConstantArbitrary(values);56            const notSeenValues = [...values];57            for (let idx = 0; idx !== values.length; ++idx) {58              nextInt.mockImplementationOnce((a, _b) => a + idx);59              const g = arb.generate(mrng, biasFactor);60              const index = notSeenValues.findIndex((v) => Object.is(g.value, v));61              expect(index).not.toBe(-1);62              notSeenValues.splice(index, 1);63            }64            expect(notSeenValues).toEqual([]);65          }66        )67      ));68    it('should produce a cloneable instance if provided value is cloneable', () => {69      // Arrange70      const expectedBiasFactor = 48;71      const cloneable = Object.defineProperty([], cloneMethod, { value: jest.fn() });72      const { instance: mrng } = fakeRandom();73      // Act74      const arb = new ConstantArbitrary([cloneable]);75      const g = arb.generate(mrng, expectedBiasFactor);76      // Assert77      expect(g.hasToBeCloned).toBe(true);78    });79    it('should clone cloneable instances for each access', () => {80      // Arrange81      const expectedBiasFactor = 48;82      const cloneMethodImpl = jest.fn();83      const cloneable = Object.defineProperty([], cloneMethod, { value: cloneMethodImpl });84      cloneMethodImpl.mockReturnValue(cloneable); // in reality it should be a clone of it, not itself85      const { instance: mrng } = fakeRandom();86      // Act87      const arb = new ConstantArbitrary([cloneable]);88      const g = arb.generate(mrng, expectedBiasFactor);89      expect(cloneMethodImpl).not.toHaveBeenCalled();90      // Assert91      g.value;92      expect(cloneMethodImpl).toHaveBeenCalledTimes(1);93      g.value;94      expect(cloneMethodImpl).toHaveBeenCalledTimes(2);95    });96  });97  describe('canShrinkWithoutContext', () => {98    it("should mark value as 'canShrinkWithoutContext' whenever one of the original values is equal regarding Object.is", () =>99      fc.assert(100        fc.property(fc.array(fc.anything(), { minLength: 1 }), fc.nat(), (values, mod) => {101          // Arrange102          const selectedValue = values[mod % values.length];103          // Act104          const arb = new ConstantArbitrary(values);105          const out = arb.canShrinkWithoutContext(selectedValue);106          // Assert107          expect(out).toBe(true);108        })109      ));110    it('should not detect values not equal regarding to Object.is', () => {111      // Arrange112      const values: unknown[] = [0, [], {}, ''];113      const selectedValue: unknown = [];114      // Act115      const arb = new ConstantArbitrary<unknown>(values);116      const out = arb.canShrinkWithoutContext(selectedValue);117      // Assert118      expect(out).toBe(false); // Object.is([], []) is falsy119    });120  });121  describe('shrink', () => {122    it('should shrink towards the first value if it was not already this one and to nil otherwise', () =>123      fc.assert(124        fc.property(fc.array(fc.anything(), { minLength: 1 }), fc.nat(), (values, mod) => {125          // Arrange126          const { instance: mrng, nextInt } = fakeRandom();127          nextInt.mockImplementation((a, b) => a + (mod % (b - a + 1)));128          // Act129          const arb = new ConstantArbitrary(values);130          const value = arb.generate(mrng, undefined);131          const shrinks = [...arb.shrink(value.value, value.context)];132          // Assert133          if (Object.is(value.value, values[0])) {134            expect(shrinks.map((v) => v.value)).toEqual([]);135          } else {136            expect(shrinks.map((v) => v.value)).toEqual([values[0]]);137          }138        })139      ));140    it('should shrink towards the first value if it was not already this one and to nil otherwise even without any context', () =>141      fc.assert(142        fc.property(fc.array(fc.anything(), { minLength: 1 }), fc.nat(), (values, mod) => {143          // Arrange144          const { instance: mrng, nextInt } = fakeRandom();145          nextInt.mockImplementation((a, b) => a + (mod % (b - a + 1)));146          // Act147          const arb = new ConstantArbitrary(values);148          const value = arb.generate(mrng, undefined);149          const shrinks = [...arb.shrink(value.value, undefined)];150          // Assert151          if (Object.is(value.value, values[0])) {152            expect(shrinks.map((v) => v.value)).toEqual([]);153          } else {154            expect(shrinks.map((v) => v.value)).toEqual([values[0]]);155          }156        })157      ));158    it('should not shrink towards the first value if generated value is equal to the first one regarding `Object.is`', () => {159      // Arrange160      const { instance: mrng, nextInt } = fakeRandom();161      // Act / Assert162      const arb = new ConstantArbitrary([Number.NaN, Number.NaN, Number.NaN]);163      for (let idx = 0; idx !== 3; ++idx) {164        nextInt.mockReturnValue(idx);165        const value = arb.generate(mrng, undefined);166        expect(value.value).toBe(Number.NaN);167        const shrinks = [...arb.shrink(value.value, value.context)];168        expect(shrinks).toHaveLength(0);169      }170    });171  });172});173describe('ConstantArbitrary (integration)', () => {174  type Extra = unknown[];175  const extraParameters: fc.Arbitrary<Extra> = fc.array(fc.anything(), { minLength: 1 });176  // In other words: extra.includes(value)                   --but with Object.is177  const isCorrect = (value: unknown, extra: Extra) => extra.findIndex((v) => Object.is(value, v)) !== -1;178  // In other words: extra.indexOf(v1) < extra.indexOf(v2)   --but with Object.is179  // If the same value has been declared twice in the `extra` once for `extra[0]` and the other for `extra[n]` (with n > 0)180  // Shrinker should never shrink `extra[n]` into `extra[0]` if they are equal regarding `Object.is`181  const isStrictlySmaller = (v1: unknown, v2: unknown, extra: Extra) =>182    extra.findIndex((v) => Object.is(v1, v)) < extra.findIndex((v) => Object.is(v2, v));183  const constantBuilder = (extra: Extra) => new ConstantArbitrary(extra);184  it('should produce the same values given the same seed', () => {185    assertProduceSameValueGivenSameSeed(constantBuilder, { extraParameters });186  });187  it('should only produce correct values', () => {188    assertProduceCorrectValues(constantBuilder, isCorrect, { extraParameters });189  });190  it('should produce values seen as shrinkable without any context', () => {191    assertProduceValuesShrinkableWithoutContext(constantBuilder, { extraParameters });192  });193  it('should preserve strictly smaller ordering in shrink', () => {194    assertShrinkProducesStrictlySmallerValue(constantBuilder, isStrictlySmaller, { extraParameters });195  });196  it('should not re-use twice the same instance of cloneable', () => {197    // Arrange198    const alreadySeenCloneable = new Set<unknown>();199    const buildCloneable = (): unknown => {200      return Object.defineProperty([], cloneMethod, { value: buildCloneable });201    };202    const arb = new ConstantArbitrary([buildCloneable()]);203    const { instance: mrng } = fakeRandom();204    // Act205    const g = arb.generate(mrng, undefined);206    const treeA = buildShrinkTree(arb, g);207    const treeB = buildShrinkTree(arb, g);208    // Assert209    walkTree(treeA, (cloneable) => {210      expect(alreadySeenCloneable.has(cloneable)).toBe(false);211      alreadySeenCloneable.add(cloneable);212    });213    walkTree(treeB, (cloneable) => {214      expect(alreadySeenCloneable.has(cloneable)).toBe(false);215      alreadySeenCloneable.add(cloneable);216    });...

constantFrom.spec.ts

Source:constantFrom.spec.ts

...9  fc.configureGlobal({ beforeEach: beforeEachHook });10}11beforeEach(beforeEachHook);12describe('constantFrom', () => {13  it('should instantiate ConstantArbitrary(csts) for constantFrom(...csts)', () =>14    fc.assert(15      fc.property(fc.array(fc.anything(), { minLength: 1 }), (csts) => {16        // Arrange17        const { instance } = fakeArbitrary();18        const ConstantArbitrary = jest.spyOn(ConstantArbitraryMock, 'ConstantArbitrary');19        ConstantArbitrary.mockImplementation(() => instance as ConstantArbitraryMock.ConstantArbitrary<unknown>);20        // Act21        const arb = constantFrom(...csts);22        // Assert23        expect(ConstantArbitrary).toHaveBeenCalledWith(csts);24        expect(arb).toBe(instance);25      })26    ));27  it('should throw when receiving no parameters', () => {...

constant.spec.ts

Source:constant.spec.ts

...9  fc.configureGlobal({ beforeEach: beforeEachHook });10}11beforeEach(beforeEachHook);12describe('constant', () => {13  it('should instantiate ConstantArbitrary([c]) for constant(c)', () =>14    fc.assert(15      fc.property(fc.anything(), (c) => {16        // Arrange17        const { instance } = fakeArbitrary();18        const ConstantArbitrary = jest.spyOn(ConstantArbitraryMock, 'ConstantArbitrary');19        ConstantArbitrary.mockImplementation(() => instance as ConstantArbitraryMock.ConstantArbitrary<unknown>);20        // Act21        const arb = constant(c);22        // Assert23        expect(ConstantArbitrary).toHaveBeenCalledWith([c]);24        expect(arb).toBe(instance);25      })26    ));27  it('should not throw on cloneable instance', () => {...

Using AI Code Generation

1const fc = require("fast-check");2const { ConstantArbitrary } = require("fast-check/lib/arbitrary/constantArbitrary");3const { array } = require("fast-check/lib/arbitrary/array");4const { tuple } = require("fast-check/lib/arbitrary/tuple");5const { integer } = require("fast-check/lib/arbitrary/integer");6const { string } = require("fast-check/lib/arbitrary/string");7const { oneof } = require("fast-check/lib/arbitrary/oneof");8const { record } = require("fast-check/lib/arbitrary/record");9const { object } = require("fast-check/lib/arbitrary/object");10const { set } = require("fast-check/lib/arbitrary/set");11const { map } = require("fast-check/lib/arbitrary/map");12const { bigInt } = require("fast-check/lib/arbitrary/bigInt");13const { date } = require("fast-check/lib/arbitrary/date");14const { double } = require("fast-check/lib/arbitrary/double");15const { float } = require("fast-check/lib/arbitrary/float");16const { boolean } = require("fast-check/lib/arbitrary/boolean");17const { char } = require("fast-check/lib/arbitrary/char");18const { unicode } = require("fast-check/lib/arbitrary/unicode");19const { unicodeString } = require("fast-check/lib/arbitrary/unicodeString");20const { fullUnicode } = require("fast-check/lib/arbitrary/fullUnicode");21const { fullUnicodeString } = require("fast-check/lib/arbitrary/fullUnicodeString");22const { hexa } = require("fast-check/lib/arbitrary/hexa");23const { hexaString } = require("fast-check/lib/arbitrary/hexaString");24const { base64 } = require("fast-check/lib/arbitrary/base64");25const { base64String } = require("fast-check/lib/arbitrary/base64String");26const { ascii } = require("fast-check/lib/arbitrary/ascii");27const { asciiString } = require("fast-check/lib/arbitrary/asciiString");28const { option } = require("fast-check/lib/arbitrary/option");29const { frequency } = require("fast-check/lib/arbitrary/frequency");30const { subarray } = require("fast-check/lib/arbitrary/subarray");31const { subarrayOf } = require("fast-check/lib/arbitrary/subarrayOf");32const { shuffle } = require("fast-check/lib/arbitrary/shuffle");33const {

Using AI Code Generation

1const { ConstantArbitrary } = require('fast-check/lib/check/arbitrary/ConstantArbitrary.js');2const { integer } = require('fast-check/lib/arbitrary/IntegerArbitrary.js');3const { property } = require('fast-check/lib/check/property/Property.js');4const { string } = require('fast-check/lib/arbitrary/StringArbitrary.js');5const arb = ConstantArbitrary.from(integer(1, 100));6const arb2 = ConstantArbitrary.from(string());7property(arb, arb2, (a, b) => {8  return a === a && b === b;9}).check();10const { ConstantArbitrary } = require('fast-check');11const { integer } = require('fast-check');12const { property } = require('fast-check');13const { string } = require('fast-check');14const arb = ConstantArbitrary.from(integer(1, 100));15const arb2 = ConstantArbitrary.from(string());16property(arb, arb2, (a, b) => {17  return a === a && b === b;18}).check();

Using AI Code Generation

1const fc = require('fast-check');2const { ConstantArbitrary } = require('fast-check/lib/arbitrary/ConstantArbitrary.js');3const constantArbitrary = new ConstantArbitrary(2);4const constantArbitrary2 = new ConstantArbitrary(3);5fc.assert(fc.property(fc.integer(), (x) => {6  return constantArbitrary.generate(1)[0] === 2 && constantArbitrary2.generate(1)[0] === 3;7}));8const constantArbitrary = new ConstantArbitrary(2); const constantArbitrary2 = new ConstantArbitrary(3); fc.assert(fc.property(fc.integer(), (x) => { return constantArbitrary.generate(1)[0] === 2 && constantArbitrary2.generate(1)[0] === 3; }));9const fc = require ( 'fast-check' ) ; const { ConstantArbitrary } = require ( 'fast-check/lib/arbitrary/ConstantArbitrary.js' ) ; const constantArbitrary = new ConstantArbitrary ( 2 ) ; const constantArbitrary2 = new ConstantArbitrary ( 3 ) ; fc . assert ( fc

Using AI Code Generation

1const { constant } = require('fast-check');2const { constantArbitrary } = constant;3const arb = constantArbitrary(1);4"dependencies": {5  },6  "devDependencies": {7  }8const { constant } = require('fast-check');9const { constantArbitrary } = constant;10const arb = constantArbitrary(1);11"scripts": {12  }13"dependencies": {14  },15  "devDependencies": {16  }17const { constant } = require('fast-check');18const { constantArbitrary } = constant;19const arb = constantArbitrary(1);20"scripts": {21  }

Using AI Code Generation

1const { ConstantArbitrary } = require('fast-check');2const arb = ConstantArbitrary('foo');3const { ConstantArbitrary } = require('fast-check/lib/check/arbitrary/ConstantArbitrary');4const arb = ConstantArbitrary('foo');5const { ConstantArbitrary } = require('fast-check');6const arb = ConstantArbitrary('foo');7It is not possible to use the latest version of fast-check with a require('fast-check') . You have to use require('fast-check/lib/check

Using AI Code Generation

1const { ConstantArbitrary } = require("fast-check");2const { constant } = require("fast-check");3const { assert } = require("chai");4const { expect } = require("chai");5describe("ConstantArbitrary", () => {6  it("should generate the same value", () => {7    const arb = new ConstantArbitrary(42);8    const out = arb.generate(mrng());9    assert.equal(out, 42);10  });11});12describe("ConstantArbitrary", () => {13  it("should generate the same value", () => {14    const arb = constant(42);15    const out = arb.generate(mrng());16    assert.equal(out, 42);17  });18});19describe("ConstantArbitrary", () => {20  it("should generate the same value", () => {21    const arb = constant(42);22    const out = arb.generate(mrng());23    expect(out).to.equal(42);24  });25});26describe("ConstantArbitrary", () => {27  it("should generate the same value", () => {28    const arb = new ConstantArbitrary(42);29    const out = arb.generate(mrng());30    expect(out).to.equal(42);31  });32});33describe("ConstantArbitrary", () => {34  it("should generate the same value", () => {35    const arb = constant(42);36    const out = arb.generate(mrng());37    assert.equal(out, 42);38  });39});40describe("ConstantArbitrary", () => {41  it("should generate the same value", () => {42    const arb = constant(42);43    const out = arb.generate(mrng());44    expect(out).to.equal(42);45  });46});47describe("ConstantArbitrary", () => {48  it("should generate the same value", () => {49    const arb = new ConstantArbitrary(42);50    const out = arb.generate(mrng());51    assert.equal(out, 42);52  });53});54describe("ConstantArbitrary", () => {55  it("should generate the same value", () => {56    const arb = constant(42);57    const out = arb.generate(mrng());58    expect(out).to.equal(42);59  });60});

Using AI Code Generation

1const fc = require("fast-check");2const { ConstantArbitrary } = require("fast-check/lib/types/arbitrary/ConstantArbitrary");3const { array } = require("fast-check/lib/types/arbitrary/ArrayArbitrary");4const { integer } = require("fast-check/lib/types/arbitrary/IntegerArbitrary");5const { Random } = require("fast-check/lib/random/generator/Random");6const { Stream } = require("fast-check/lib/stream/Stream");7const { RandomArray } = require("fast-check/lib/random/RandomArray");8const { RandomInteger } = require("fast-check/lib/random/RandomInteger");9const random = new Random(RandomArray);10const intArray = array(new ConstantArbitrary(new RandomInteger(0, 100), random), 10);11intArray.generate(random).value;12const fc = require("fast-check");13const { array } = require("fast-check/lib/types/arbitrary/ArrayArbitrary");14const { integer } = require("fast-check/lib/types/arbitrary/IntegerArbitrary");15const intArray = array(integer(0, 100), 10);16intArray.generate().value;

Using AI Code Generation

1const { constant } = require('fast-check');2const constantArbitrary = constant('hello');3const result = constantArbitrary.generate();4console.log(result);5const { constant } = require('fast-check');6const constantArbitrary = constant('hello');7const result = constantArbitrary.generate();8console.log(result);9const { constant } = require('fast-check');10const constantArbitrary = constant('hello');11const result = constantArbitrary.generate();12console.log(result);13const { constant } = require('fast-check');14const constantArbitrary = constant('hello');15const result = constantArbitrary.generate();16console.log(result);17const { constant } = require('fast-check');18const constantArbitrary = constant('hello');19const result = constantArbitrary.generate();20console.log(result);21const { constant } = require('fast-check');22const constantArbitrary = constant('hello');23const result = constantArbitrary.generate();24console.log(result);25const { constant } = require('fast-check');26const constantArbitrary = constant('hello');27const result = constantArbitrary.generate();28console.log(result);29const { constant } = require('fast-check');30const constantArbitrary = constant('hello');31const result = constantArbitrary.generate();32console.log(result);33const { constant } = require('fast-check');34const constantArbitrary = constant('hello');35const result = constantArbitrary.generate();36console.log(result);37const { constant } = require('fast-check');

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