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How to use shrinkTreeB method in fast-check-monorepo

Best JavaScript code snippet using fast-check-monorepo

Arbitrary.itest.spec.ts

1import { Arbitrary } from '../../../../../src/check/arbitrary/definition/Arbitrary';2import { Value } from '../../../../../src/check/arbitrary/definition/Value';3import { cloneMethod, hasCloneMethod } from '../../../../../src/check/symbols';4import { Random } from '../../../../../src/random/generator/Random';5import { Stream } from '../../../../../src/stream/Stream';6import * as stubRng from '../../../stubs/generators';7import { buildShrinkTree, renderTree, walkTree } from '../../../arbitrary/__test-helpers__/ShrinkTree';8const mrngNoCall = stubRng.mutable.nocall();9describe('Arbitrary', () => {10  describe('map', () => {11    it('should produce the right shrinking tree', () => {12      // Arrange13      class MyArbitrary extends Arbitrary<number> {14        generate(_mrng: Random): Value<number> {15          return new Value(10, { step: 2 });16        }17        canShrinkWithoutContext(value: unknown): value is number {18          throw new Error('No call expected in current scenario');19        }20        shrink(value: number, context?: unknown): Stream<Value<number>> {21          if (typeof context !== 'object' || context === null || !('step' in context)) {22            throw new Error('Invalid context for MyArbitrary');23          }24          const currentStep = (context as { step: number }).step;25          const nextStep = currentStep + 1;26          return Stream.of(27            ...(value - currentStep >= 0 ? [new Value(value - currentStep, { step: nextStep })] : []),28            ...(value - 1 >= 0 ? [new Value(value - 1, { step: nextStep })] : [])29          );30        }31      }32      const arb = new MyArbitrary().map((n) => String(n));33      // Act34      const g = arb.generate(mrngNoCall, undefined);35      const renderedTree = renderTree(buildShrinkTree(arb, g)).join('\n');36      // Assert37      expect(renderedTree).toMatchInlineSnapshot(`38        ""10"39        â> "8"40        |  â> "5"41        |  |  â> "1"42        |  |  |  â> "0"43        |  |  â> "4"44        |  |     â> "3"45        |  |        â> "2"46        |  |           â> "1"47        |  |              â> "0"48        |  â> "7"49        |     â> "3"50        |     |  â> "2"51        |     |     â> "1"52        |     |        â> "0"53        |     â> "6"54        |        â> "1"55        |        |  â> "0"56        |        â> "5"57        |           â> "4"58        |              â> "3"59        |                 â> "2"60        |                    â> "1"61        |                       â> "0"62        â> "9"63           â> "6"64           |  â> "2"65           |  |  â> "1"66           |  |     â> "0"67           |  â> "5"68           |     â> "0"69           |     â> "4"70           |        â> "3"71           |           â> "2"72           |              â> "1"73           |                 â> "0"74           â> "8"75              â> "4"76              |  â> "3"77              |     â> "2"78              |        â> "1"79              |           â> "0"80              â> "7"81                 â> "2"82                 |  â> "1"83                 |     â> "0"84                 â> "6"85                    â> "0"86                    â> "5"87                       â> "4"88                          â> "3"89                             â> "2"90                                â> "1"91                                   â> "0""92      `);93    });94    it('should preserve cloneable capabilities during both generation and shrinking process', () => {95      // Arrange96      type MyArbitraryOutput = { value: number };97      class MyArbitrary extends Arbitrary<MyArbitraryOutput> {98        private create(value: number): MyArbitraryOutput {99          const complexInstance = { value, [cloneMethod]: () => this.create(value) };100          return complexInstance;101        }102        generate(_mrng: Random): Value<MyArbitraryOutput> {103          return new Value(this.create(10), undefined);104        }105        canShrinkWithoutContext(value: unknown): value is MyArbitraryOutput {106          throw new Error('No call expected in current scenario');107        }108        shrink(v: MyArbitraryOutput, _context?: unknown): Stream<Value<MyArbitraryOutput>> {109          const value = v.value;110          return Stream.of(111            ...(value - 2 >= 0 ? [new Value(this.create(value - 2), undefined)] : []),112            ...(value - 1 >= 0 ? [new Value(this.create(value - 1), undefined)] : [])113          );114        }115      }116      const seenInstances = new Set<unknown>();117      const arb = new MyArbitrary().map((out) => ({ stringValue: String(out.value), counter: 0 }));118      // Act119      const g = arb.generate(mrngNoCall, undefined);120      const shrinkTree = buildShrinkTree(arb, g);121      const shrinkTreeB = buildShrinkTree(arb, g);122      // Assert123      const visit = (instance: { counter: number }) => {124        expect(hasCloneMethod(instance)).toBe(true); // clone method should be provided125        expect(instance.counter).toBe(0); // counter should be unique per cloned instance126        expect(seenInstances.has(instance)).toBe(false); // each instance must appear only once in the tree127        instance.counter += 1;128        seenInstances.add(instance);129      };130      walkTree(shrinkTree, visit);131      walkTree(shrinkTreeB, visit);132    });133    it('should preserve cloneable capabilities during both generation and shrinking process even if output of map is already cloneable', () => {134      // Arrange135      type MyArbitraryOutput = { value: number; counter: number };136      class MyArbitrary extends Arbitrary<MyArbitraryOutput> {137        private create(value: number): MyArbitraryOutput {138          const complexInstance = { value, counter: 0, [cloneMethod]: () => this.create(value) };139          return complexInstance;140        }141        generate(_mrng: Random): Value<MyArbitraryOutput> {142          return new Value(this.create(10), undefined);143        }144        canShrinkWithoutContext(value: unknown): value is MyArbitraryOutput {145          throw new Error('No call expected in current scenario');146        }147        shrink(v: MyArbitraryOutput, _context?: unknown): Stream<Value<MyArbitraryOutput>> {148          const value = v.value;149          return Stream.of(150            ...(value - 2 >= 0 ? [new Value(this.create(value - 2), undefined)] : []),151            ...(value - 1 >= 0 ? [new Value(this.create(value - 1), undefined)] : [])152          );153        }154      }155      const seenInstances = new Set<unknown>();156      const arb = new MyArbitrary().map((out) => out); // out is already cloneable157      // Act158      const g = arb.generate(mrngNoCall, undefined);159      const shrinkTree = buildShrinkTree(arb, g);160      const shrinkTreeB = buildShrinkTree(arb, g);161      // Assert162      const visit = (instance: { counter: number }) => {163        expect(hasCloneMethod(instance)).toBe(true); // clone method should be provided164        expect(instance.counter).toBe(0); // counter should be unique per cloned instance165        expect(seenInstances.has(instance)).toBe(false); // each instance must appear only once in the tree166        instance.counter += 1;167        seenInstances.add(instance);168      };169      walkTree(shrinkTree, visit);170      walkTree(shrinkTreeB, visit);171    });172  });173  describe('chain', () => {174    it('should produce the right shrinking tree', () => {175      // Arrange176      class MyArbitrary extends Arbitrary<number> {177        generate(_mrng: Random): Value<number> {178          return new Value(5, { step: 2 });179        }180        canShrinkWithoutContext(value: unknown): value is number {181          throw new Error('No call expected in current scenario');182        }183        shrink(value: number, context?: unknown): Stream<Value<number>> {184          if (typeof context !== 'object' || context === null || !('step' in context)) {185            throw new Error('Invalid context for MyArbitrary');186          }187          const currentStep = (context as { step: number }).step;188          if (value - currentStep < 0) {189            return Stream.nil();190          }191          const nextStep = currentStep + 1;192          return Stream.of(new Value(value - currentStep, { step: nextStep }));193        }194      }195      class MyChainedArbitrary extends Arbitrary<number[]> {196        constructor(readonly size: number, readonly value: number) {197          super();198        }199        generate(_mrng: Random): Value<number[]> {200          return new Value(Array(this.size).fill(this.value), {201            size: this.size,202            value: this.value,203          });204        }205        canShrinkWithoutContext(value: unknown): value is number[] {206          throw new Error('No call expected in current scenario');207        }208        shrink(value: number[], context?: unknown): Stream<Value<number[]>> {209          if (typeof context !== 'object' || context === null || !('size' in context) || !('value' in context)) {210            throw new Error('Invalid context for MyChainedArbitrary');211          }212          const currentContext = context as { size: number; value: number };213          if (currentContext.size === 0) {214            return Stream.nil();215          }216          return Stream.of(217            ...(currentContext.value === value[0]218              ? [new Value(Array(currentContext.size).fill(0), currentContext)]219              : []),220            ...(value.length > 1 ? [new Value([value[0]], currentContext)] : [])221          );222        }223      }224      const arb = new MyArbitrary().chain((n) => new MyChainedArbitrary(n, n));225      // Act226      const g = arb.generate(mrngNoCall, undefined);227      const renderedTree = renderTree(buildShrinkTree(arb, g)).join('\n');228      // Assert229      expect(renderedTree).toMatchInlineSnapshot(`230        "[5,5,5,5,5]231        â> [3,3,3]232        |  â> []233        |  â> [0,0,0]234        |  |  â> [0]235        |  â> [3]236        |     â> [0,0,0]237        |        â> [0]238        â> [0,0,0,0,0]239        |  â> [0]240        â> [5]241           â> [0,0,0,0,0]242              â> [0]"243      `);244    });245  });246  describe('filter', () => {247    it('should produce the right shrinking tree', () => {248      // Arrange249      class MyArbitrary extends Arbitrary<number> {250        generate(_mrng: Random): Value<number> {251          return new Value(10, { step: 3 });252        }253        canShrinkWithoutContext(value: unknown): value is number {254          throw new Error('No call expected in current scenario');255        }256        shrink(value: number, context?: unknown): Stream<Value<number>> {257          if (typeof context !== 'object' || context === null || !('step' in context)) {258            throw new Error('Invalid context for MyArbitrary');259          }260          const currentStep = (context as { step: number }).step;261          const nextStep = currentStep + 1;262          return Stream.of(263            ...(value - currentStep >= 0 ? [new Value(value - currentStep, { step: nextStep })] : []),264            ...(value - 2 >= 0 ? [new Value(value - 2, { step: nextStep })] : []),265            ...(value - 1 >= 0 ? [new Value(value - 1, { step: nextStep })] : [])266          );267        }268      }269      const arb = new MyArbitrary().filter((n) => n % 2 === 0);270      // Act271      const g = arb.generate(mrngNoCall, undefined);272      const renderedTree = renderTree(buildShrinkTree(arb, g)).join('\n');273      // Assert274      expect(renderedTree).toMatchInlineSnapshot(`275        "10276        â> 8277           â> 4278           |  â> 2279           |     â> 0280           â> 6281              â> 4282                 â> 2283                    â> 0"284      `);285    });286  });...

Using AI Code Generation

1const shrinkTreeB = require('fast-check-monorepo').shrinkTreeB;2const shrinkTreeB = require('fast-check').shrinkTreeB;3const shrinkTreeB = require('fast-check-monorepo').shrinkTreeB;4const shrinkTreeB = require('fast-check').shrinkTreeB;5const shrinkTreeB = require('fast-check-monorepo').shrinkTreeB;6const shrinkTreeB = require('fast-check').shrinkTreeB;7const shrinkTreeB = require('fast-check-monorepo').shrinkTreeB;8const shrinkTreeB = require('fast-check').shrinkTreeB;9const shrinkTreeB = require('fast-check-monorepo').shrinkTreeB;10const shrinkTreeB = require('fast-check').shrinkTreeB;11const shrinkTreeB = require('fast-check-monorepo').shrinkTreeB;12const shrinkTreeB = require('fast-check').shrinkTreeB;13const shrinkTreeB = require('fast-check-monorepo').shrinkTreeB;14const shrinkTreeB = require('fast-check').shrinkTreeB;15const shrinkTreeB = require('fast-check-monorepo').shrinkTreeB;16const shrinkTreeB = require('fast-check').shrinkTreeB;17const shrinkTreeB = require('fast-check-monorepo').shrinkTreeB;

Using AI Code Generation

1const { shrinkTreeB } = require('fast-check-monorepo')2const { shrinkTreeB } = require('fast-check')3const { shrinkTreeB } = require('fast-check-monorepo')4const { shrinkTreeB } = require('fast-check')5I am using the following code to import the shrinkTreeB method from fast-check-monorepo and fast-check6const { shrinkTreeB } = require('fast-check-monorepo')7const { shrinkTreeB } = require('fast-check')8const { shrinkTreeB } = require('fast-check-monorepo')9const { shrinkTreeB } = require('fast-check')10I am using the following code to import the shrinkTreeB method from fast-check-monorepo and fast-check11const { shrinkTreeB } = require('fast-check-monorepo')12const { shrinkTreeB } = require('fast-check')13const { shrinkTreeB } = require('fast-check-monorepo')14const { shrinkTreeB } = require('fast-check')15I am using the following code to import the shrinkTreeB method from fast-check-monorepo and fast-check16const { shrinkTreeB } = require('fast-check-monorepo')17const { shrinkTreeB } = require('fast-check')18const { shrinkTreeB } = require('fast-check-monorepo')19const { shrinkTreeB } = require('fast-check')20I am using the following code to import the shrinkTreeB method from fast-check-monorepo and fast-check21const { shrinkTreeB } = require('fast-check-monorepo')22const { shrinkTreeB } = require('fast-check')23const { shrinkTreeB } = require('fast-check-monorepo')24const { shrinkTreeB } = require('fast-check')25I am using the following code to import the shrinkTreeB method from fast-check-monorepo and fast-check26const { shrinkTreeB } = require('fast-check-monorepo')27const { shrinkTreeB } = require('fast-check')28const { shrinkTreeB } = require('fast-check-monorepo')29const { shrinkTreeB } = require('fast-check')30I am using the following code to import the shrinkTreeB method from

Using AI Code Generation

1const { shrinkTreeB } = require('fast-check-monorepo');2console.log(shrinkTreeB(1, 2));3{4  "scripts": {5  },6  "dependencies": {7  }8}

Using AI Code Generation

1const {shrinkTreeB} = require('fast-check-monorepo');2const {shrinkTree} = require('fast-check');3const {shrinkTree} = require('fast-check');4const tree = {value: 1, children: [{value: 2, children: []}]};5const shrunkTree = shrinkTreeB(tree, (t) => t.value);6console.log(shrunkTree);7const {shrinkTreeB} = require('fast-check-monorepo');8const {shrinkTree} = require('fast-check');9const {shrinkTree} = require('fast-check');10const tree = {value: 1, children: [{value: 2, children: []}]};11const shrunkTree = shrinkTreeB(tree, (t) => t.value);12console.log(shrunkTree);

Using AI Code Generation

1const { shrinkTreeB } = require('fast-check-monorepo');2const { shrinkTree } = require('fast-check');3const initialArray = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];4const shrinkArray = shrinkTreeB(shrinkTree, initialArray);5for (const shrinkedArray of shrinkArray) {6  console.log(shrinkedArray);7}8const { shrinkTreeB } = require('fast-check');9const { shrinkTree } = require('fast-check');10const initialArray = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];11const shrinkArray = shrinkTreeB(shrinkTree, initialArray);12for (const shrinkedArray of shrinkArray) {13  console.log(shrinkedArray);14}

Using AI Code Generation

1const fc = require('fast-check');2const { shrinkTreeB } = require('fast-check-monorepo');3const shrinkTree = shrinkTreeB(fc);4test('sample test', () => {5  fc.assert(6    fc.property(fc.array(fc.integer()), (arr) => {7      const shrunk = shrinkTree(arr);8      const shrunkArr = [...shrunk];9      return expect(shrunkArr).toEqual([]);10    })11  );12});13test('test with error', () => {14  fc.assert(15    fc.property(fc.array(fc.integer()), (arr) => {16      const shrunk = shrinkTree(arr);17      const shrunkArr = [...shrunk];18      return expect(shrunkArr).toEqual([[]]);19    })20  );21});22test('test with error', () => {23  fc.assert(24    fc.property(fc.array(fc.integer()), (arr) => {25      const shrunk = shrinkTree(arr);26      const shrunkArr = [...shrunk];27      return expect(shrunkArr).toEqual([[]]);28    })29  );30});31Thanks for the report. I am not sure that I understand the issue. Could you please provide a minimal reproducible example (e.g. a github repository)?

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