How to use depthImpact method in fast-check-monorepo

Best JavaScript code snippet using fast-check-monorepo

ArrayArbitrary.ts

Source:ArrayArbitrary.ts

1import { Random } from '../../random/generator/Random';2import { Stream } from '../../stream/Stream';3import { cloneIfNeeded, cloneMethod } from '../../check/symbols';4import { integer } from '../integer';5import { makeLazy } from '../../stream/LazyIterableIterator';6import { Arbitrary } from '../../check/arbitrary/definition/Arbitrary';7import { Value } from '../../check/arbitrary/definition/Value';8import { CustomSetBuilder } from './interfaces/CustomSet';9import { DepthContext, DepthIdentifier, getDepthContextFor } from './helpers/DepthContext';10import { buildSlicedGenerator } from './helpers/BuildSlicedGenerator';11import { safeMap, safePush, safeSlice } from '../../utils/globals';12const safeMathFloor = Math.floor;13const safeMathLog = Math.log;14const safeMathMax = Math.max;15const safeArrayIsArray = Array.isArray;16/** @internal */17type ArrayArbitraryContext = {18  shrunkOnce: boolean;19  lengthContext: unknown;20  itemsContexts: unknown[];21  startIndex: number;22};23/** @internal */24function biasedMaxLength(minLength: number, maxLength: number): number {25  if (minLength === maxLength) {26    return minLength;27  }28  return minLength + safeMathFloor(safeMathLog(maxLength - minLength) / safeMathLog(2));29}30/** @internal */31export class ArrayArbitrary<T> extends Arbitrary<T[]> {32  readonly lengthArb: Arbitrary<number>;33  readonly depthContext: DepthContext;34  constructor(35    readonly arb: Arbitrary<T>,36    readonly minLength: number,37    readonly maxGeneratedLength: number,38    readonly maxLength: number,39    depthIdentifier: DepthIdentifier | string | undefined,40    // Whenever passing a isEqual to ArrayArbitrary, you also have to filter41    // it's output just in case produced values are too small (below minLength)42    readonly setBuilder: CustomSetBuilder<Value<T>> | undefined,43    readonly customSlices: T[][]44  ) {45    super();46    this.lengthArb = integer({ min: minLength, max: maxGeneratedLength });47    this.depthContext = getDepthContextFor(depthIdentifier);48  }49  private preFilter(tab: Value<T>[]): Value<T>[] {50    if (this.setBuilder === undefined) {51      return tab;52    }53    const s = this.setBuilder();54    for (let index = 0; index !== tab.length; ++index) {55      s.tryAdd(tab[index]);56    }57    return s.getData();58  }59  private static makeItCloneable<T>(vs: T[], shrinkables: Value<T>[]) {60    (vs as any)[cloneMethod] = () => {61      const cloned: T[] = [];62      for (let idx = 0; idx !== shrinkables.length; ++idx) {63        safePush(cloned, shrinkables[idx].value); // push potentially cloned values64      }65      this.makeItCloneable(cloned, shrinkables);66      return cloned;67    };68    return vs;69  }70  private generateNItemsNoDuplicates(71    setBuilder: CustomSetBuilder<Value<T>>,72    N: number,73    mrng: Random,74    biasFactorItems: number | undefined75  ): Value<T>[] {76    let numSkippedInRow = 0;77    const s = setBuilder();78    const slicedGenerator = buildSlicedGenerator(this.arb, mrng, this.customSlices, biasFactorItems);79    // Try to append into items up to the target size80    // We may reject some items as they are already part of the set81    // so we need to retry and generate other ones. In order to prevent infinite loop,82    // we accept a max of maxGeneratedLength consecutive failures. This circuit breaker may cause83    // generated to be smaller than the minimal accepted one.84    while (s.size() < N && numSkippedInRow < this.maxGeneratedLength) {85      const current = slicedGenerator.next();86      if (s.tryAdd(current)) {87        numSkippedInRow = 0;88      } else {89        numSkippedInRow += 1;90      }91    }92    return s.getData();93  }94  private safeGenerateNItemsNoDuplicates(95    setBuilder: CustomSetBuilder<Value<T>>,96    N: number,97    mrng: Random,98    biasFactorItems: number | undefined99  ): Value<T>[] {100    const depthImpact = safeMathMax(0, N - biasedMaxLength(this.minLength, this.maxGeneratedLength)); // no depth impact for biased lengths101    this.depthContext.depth += depthImpact; // increase depth102    try {103      return this.generateNItemsNoDuplicates(setBuilder, N, mrng, biasFactorItems);104    } finally {105      this.depthContext.depth -= depthImpact; // decrease depth (reset depth)106    }107  }108  private generateNItems(N: number, mrng: Random, biasFactorItems: number | undefined): Value<T>[] {109    const items: Value<T>[] = [];110    const slicedGenerator = buildSlicedGenerator(this.arb, mrng, this.customSlices, biasFactorItems);111    slicedGenerator.attemptExact(N);112    for (let index = 0; index !== N; ++index) {113      const current = slicedGenerator.next();114      safePush(items, current);115    }116    return items;117  }118  private safeGenerateNItems(N: number, mrng: Random, biasFactorItems: number | undefined): Value<T>[] {119    const depthImpact = safeMathMax(0, N - biasedMaxLength(this.minLength, this.maxGeneratedLength)); // no depth impact for biased lengths120    this.depthContext.depth += depthImpact; // increase depth121    try {122      return this.generateNItems(N, mrng, biasFactorItems);123    } finally {124      this.depthContext.depth -= depthImpact; // decrease depth (reset depth)125    }126  }127  private wrapper(128    itemsRaw: Value<T>[],129    shrunkOnce: boolean,130    itemsRawLengthContext: unknown,131    startIndex: number132  ): Value<T[]> {133    // We need to explicitly apply filtering on shrink items134    // has they might have duplicates (on non shrunk it is not the case by construct)135    const items = shrunkOnce ? this.preFilter(itemsRaw) : itemsRaw;136    let cloneable = false;137    const vs: T[] = [];138    const itemsContexts: unknown[] = [];139    for (let idx = 0; idx !== items.length; ++idx) {140      const s = items[idx];141      cloneable = cloneable || s.hasToBeCloned;142      safePush(vs, s.value);143      safePush(itemsContexts, s.context);144    }145    if (cloneable) {146      ArrayArbitrary.makeItCloneable(vs, items);147    }148    const context: ArrayArbitraryContext = {149      shrunkOnce,150      lengthContext:151        itemsRaw.length === items.length && itemsRawLengthContext !== undefined152          ? itemsRawLengthContext // items and itemsRaw have the same length context is applicable153          : undefined,154      itemsContexts,155      startIndex,156    };157    return new Value(vs, context);158  }159  generate(mrng: Random, biasFactor: number | undefined): Value<T[]> {160    const biasMeta = this.applyBias(mrng, biasFactor);161    const targetSize = biasMeta.size;162    const items =163      this.setBuilder !== undefined164        ? this.safeGenerateNItemsNoDuplicates(this.setBuilder, targetSize, mrng, biasMeta.biasFactorItems)165        : this.safeGenerateNItems(targetSize, mrng, biasMeta.biasFactorItems);166    return this.wrapper(items, false, undefined, 0);167  }168  private applyBias(mrng: Random, biasFactor: number | undefined): { size: number; biasFactorItems?: number } {169    if (biasFactor === undefined) {170      // We don't bias anything171      return { size: this.lengthArb.generate(mrng, undefined).value };172    }173    // We directly forward bias to items whenever no bias applicable onto length174    if (this.minLength === this.maxGeneratedLength) {175      // We only apply bias on items176      return { size: this.lengthArb.generate(mrng, undefined).value, biasFactorItems: biasFactor };177    }178    if (mrng.nextInt(1, biasFactor) !== 1) {179      // We don't bias anything180      return { size: this.lengthArb.generate(mrng, undefined).value };181    }182    // We apply bias (1 chance over biasFactor)183    if (mrng.nextInt(1, biasFactor) !== 1 || this.minLength === this.maxGeneratedLength) {184      // We only apply bias on items ((biasFactor-1) chances over biasFactorÂ²)185      return { size: this.lengthArb.generate(mrng, undefined).value, biasFactorItems: biasFactor };186    }187    // We apply bias for both items and length (1 chance over biasFactorÂ²)188    const maxBiasedLength = biasedMaxLength(this.minLength, this.maxGeneratedLength);189    const targetSizeValue = integer({ min: this.minLength, max: maxBiasedLength }).generate(mrng, undefined);190    return { size: targetSizeValue.value, biasFactorItems: biasFactor };191  }192  canShrinkWithoutContext(value: unknown): value is T[] {193    if (!safeArrayIsArray(value) || this.minLength > value.length || value.length > this.maxLength) {194      return false;195    }196    for (let index = 0; index !== value.length; ++index) {197      if (!(index in value)) {198        // sparse array cannot be produced by this instance199        return false;200      }201      if (!this.arb.canShrinkWithoutContext(value[index])) {202        // item at index cannot be produced by our arbitrary203        return false;204      }205    }206    // `preFilter` only drops items, it does not reorder them or add some more207    // if calling it with `value` results into a smaller array it means that the value was not generated by this instance208    const filtered = this.preFilter(safeMap(value, (item) => new Value(item, undefined)));209    return filtered.length === value.length;210  }211  private shrinkItemByItem(212    value: T[],213    safeContext: ArrayArbitraryContext,214    endIndex: number215  ): IterableIterator<[Value<T>[], unknown, number]> {216    let shrinks = Stream.nil<[Value<T>[], unknown, number]>();217    for (let index = safeContext.startIndex; index < endIndex; ++index) {218      shrinks = shrinks.join(219        makeLazy(() =>220          this.arb.shrink(value[index], safeContext.itemsContexts[index]).map((v): [Value<T>[], unknown, number] => {221            const beforeCurrent = safeMap(222              safeSlice(value, 0, index),223              (v, i) => new Value(cloneIfNeeded(v), safeContext.itemsContexts[i])224            );225            const afterCurrent = safeMap(226              safeSlice(value, index + 1),227              (v, i) => new Value(cloneIfNeeded(v), safeContext.itemsContexts[i + index + 1])228            );229            return [230              [...beforeCurrent, v, ...afterCurrent],231              undefined, // no length context232              index, // avoid shrinking entries before index in sub-shrinks233            ];234          })235        )236      );237    }238    return shrinks;239  }240  private shrinkImpl(value: T[], context?: unknown): Stream<[Value<T>[], unknown, number]> {241    if (value.length === 0) {242      return Stream.nil();243    }244    const safeContext: ArrayArbitraryContext =245      context !== undefined246        ? (context as ArrayArbitraryContext)247        : { shrunkOnce: false, lengthContext: undefined, itemsContexts: [], startIndex: 0 };248    return (249      this.lengthArb250        .shrink(251          value.length,252          // lengthContext is a context returned by a previous call to the integer253          // arbitrary and the integer value items.length.254          safeContext.lengthContext255        )256        // in case we already shrunk once but don't have any dedicated context to help the shrinker, we drop the first item257        // except if reached we have the minimal size +1, in that case we apply a last chance try policy258        .drop(259          safeContext.shrunkOnce && safeContext.lengthContext === undefined && value.length > this.minLength + 1 ? 1 : 0260        )261        .map((lengthValue): [Value<T>[], unknown, number] => {262          const sliceStart = value.length - lengthValue.value;263          return [264            safeMap(265              safeSlice(value, sliceStart),266              (v, index) => new Value(cloneIfNeeded(v), safeContext.itemsContexts[index + sliceStart])267            ), // array of length lengthValue.value268            lengthValue.context, // integer context for value lengthValue.value (the length)269            0,270          ];271        })272        // Length context value will be set to undefined for remaining shrinking values273        // as they are outside of our shrinking process focused on items.length.274        // None of our computed contexts will apply for them.275        .join(276          makeLazy(() =>277            value.length > this.minLength278              ? this.shrinkItemByItem(value, safeContext, 1)279              : this.shrinkItemByItem(value, safeContext, value.length)280          )281        )282        .join(283          value.length > this.minLength284            ? makeLazy(() => {285                // We pass itemsLengthContext=undefined to next shrinker to start shrinking286                // without any assumptions on the current state (we never explored that one)287                const subContext: ArrayArbitraryContext = {288                  shrunkOnce: false,289                  lengthContext: undefined,290                  itemsContexts: safeSlice(safeContext.itemsContexts, 1),291                  startIndex: 0,292                };293                return this.shrinkImpl(safeSlice(value, 1), subContext)294                  .filter((v) => this.minLength <= v[0].length + 1)295                  .map((v): [Value<T>[], unknown, number] => {296                    return [[new Value(cloneIfNeeded(value[0]), safeContext.itemsContexts[0]), ...v[0]], undefined, 0];297                  });298              })299            : Stream.nil()300        )301    );302  }303  shrink(value: T[], context?: unknown): Stream<Value<T[]>> {304    return this.shrinkImpl(value, context).map((contextualValue) =>305      this.wrapper(contextualValue[0], true, contextualValue[1], contextualValue[2])306    );307  }...

Using AI Code Generation

1const { check, property } = require('fast-check');2const { depthImpact } = require('fast-check-monorepo');3const isPrime = (n) => {4    if (n <= 1) {5        return false;6    }7    for (let i = 2; i < n; i++) {8        if (n % i === 0) {9            return false;10        }11    }12    return true;13}14const isPrimeArb = (min, max) => {15    return property(depthImpact((n) => {16        return n >= min && n <= max;17    }, 1), isPrime);18}19const isPrimeArb2 = (min, max) => {20    return property(depthImpact((n) => {21        return n >= min && n <= max;22    }, 2), isPrime);23}24const isPrimeArb3 = (min, max) => {25    return property(depthImpact((n) => {26        return n >= min && n <= max;27    }, 3), isPrime);28}29describe('isPrime', () => {30    it('should work', () => {31        check(isPrimeArb(2, 1000), { numRuns: 10000 });32    });33    it('should work with depth impact 2', () => {34        check(isPrimeArb2(2, 1000), { numRuns: 10000 });35    });36    it('should work with depth impact 3', () => {37        check(isPrimeArb3(2, 1000), { numRuns: 10000 });38    });39});40const { depthImpact } = require('fast-check-monorepo');41const isPrime = (n) => {42    if (n <= 1) {43        return false;44    }45    for (let i = 2; i < n; i++) {46        if (n % i === 0) {47            return false;48        }49    }50    return true;51}52const isPrimeArb = (min, max) => {53    return property(depthImpact((n) => {

Using AI Code Generation

1const { depthImpact } = require('fast-check-monorepo');2const impact = depthImpact(3);3console.log(impact);4const { depthImpact } = require('fast-check-monorepo');5const impact = depthImpact(4);6console.log(impact);7const { depthImpact } = require('fast-check-monorepo');8const impact = depthImpact(5);9console.log(impact);10const { depthImpact } = require('fast-check-monorepo');11const impact = depthImpact(6);12console.log(impact);13const { depthImpact } = require('fast-check-monorepo');14const impact = depthImpact(7);15console.log(impact);16const { depthImpact } = require('fast-check-monorepo');17const impact = depthImpact(8);18console.log(impact);19const { depthImpact } = require('fast-check-monorepo');20const impact = depthImpact(9);21console.log(impact);22const { depthImpact } = require('fast-check-monorepo');23const impact = depthImpact(10);24console.log(impact);25const { depthImpact } = require('fast-check-monorepo');26const impact = depthImpact(11);27console.log(impact);28const { depthImpact } = require('fast-check-monorepo');29const impact = depthImpact(12);30console.log(impact);31const { depthImpact } = require('fast-check-monorepo');

Using AI Code Generation

1const { depthImpact } = require("fast-check-monorepo");2const test3 = () => {3  const res = depthImpact(3);4  console.log(res);5};6test3();7const { depthImpact } = require("fast-check-monorepo");8const test4 = () => {9  const res = depthImpact(4);10  console.log(res);11};12test4();13const { depthImpact } = require("fast-check-monorepo");14const test5 = () => {15  const res = depthImpact(5);16  console.log(res);17};18test5();19const { depthImpact } = require("fast-check-monorepo");20const test6 = () => {21  const res = depthImpact(6);22  console.log(res);23};24test6();25const { depthImpact } = require("fast-check-monorepo");26const test7 = () => {27  const res = depthImpact(7);28  console.log(res);29};30test7();31const { depthImpact } = require("fast-check-monorepo");32const test8 = () => {33  const res = depthImpact(8);34  console.log(res);35};36test8();37const { depthImpact } = require("fast-check-monorepo");38const test9 = () => {39  const res = depthImpact(9);40  console.log(res);41};42test9();43const { depthImpact } = require("fast-check-monorepo");44const test10 = () => {45  const res = depthImpact(10);46  console.log(res);47};48test10();49const { depthImpact } = require("fast-check-monorepo");

Using AI Code Generation

1const fc = require('fast-check');2const { depthImpact } = require('fast-check-monorepo');3const m = 100;4const n = 100;5fc.assert(6  fc.property(fc.integer(0, m), fc.integer(0, n), (a, b) => {7    const result = a + b;8    return result >= 0 && result <= m + n;9  }),10  { depthImpact: depthImpact(1, m) }11);12const fc = require('fast-check');13const { depthImpact } = require('fast-check-monorepo');14const m = 100;15const n = 100;16fc.assert(17  fc.property(fc.integer(0, m), fc.integer(0, n), (a, b) => {18    const result = a + b;19    return result >= 0 && result <= m + n;20  }),21  { depthImpact: depthImpact(1, n) }22);23const fc = require('fast-check');24const { depthImpact } = require('fast-check-monorepo');25const m = 100;26const n = 100;27fc.assert(28  fc.property(fc.integer(0, m), fc.integer(0, n), (a, b) => {29    const result = a + b;30    return result >= 0 && result <= m + n;31  }),32  { depthImpact: depthImpact(1, m + n) }33);34const fc = require('fast-check');35const { depthImpact } = require('fast-check-monorepo');36const m = 100;37const n = 100;38fc.assert(39  fc.property(fc.integer(0, m), fc.integer(0, n), (a, b) => {40    const result = a + b;41    return result >= 0 && result <= m + n;42  }),43  { depthImpact: depthImpact(1, m + n + 1) }44);45const fc = require('fast-check');46const { depthImpact } = require

Using AI Code Generation

1const { depthImpact } = require("fast-check");2const impact = depthImpact({3});4console.log(impact);5const { depthImpact } = require("fast-check");6const impact = depthImpact({7});8console.log(impact);9const { depthImpact } = require("fast-check");10const impact = depthImpact({11});12console.log(impact);13const { depthImpact } = require("fast-check");14const impact = depthImpact({15});16console.log(impact);17const { depthImpact } = require("fast-check");18const impact = depthImpact({19});20console.log(impact);21const { depthImpact } = require("fast-check");22const impact = depthImpact({23});24console.log(impact);25const { depthImpact } = require("fast-check");26const impact = depthImpact({27});28console.log(impact);29const { depthImpact } = require("fast-check");30const impact = depthImpact({31});32console.log(impact);

Using AI Code Generation

1const fc = require("fast-check");2const { depthImpact } = require("fast-check-monorepo");3const myArbitrary = fc.string();4const myArbitrary2 = fc.string();5  .tuple(myArbitrary, myArbitrary2)6  .map(([a, b]) => a + b);7const impact = depthImpact(myArbitrary3);8const impact2 = depthImpact(myArbitrary);9const impact3 = depthImpact(myArbitrary2);

Using AI Code Generation

1const { depthImpact } = require("fast-check-monorepo");2const impact = depthImpact("test2.js", "test2.js");3console.log("impact", impact);4const { depthImpact } = require("fast-check-monorepo");5const impact = depthImpact("test3.js", "test3.js");6console.log("impact", impact);7const { depthImpact } = require("fast-check-monorepo");8const impact = depthImpact("test4.js", "test4.js");9console.log("impact", impact);10const { depthImpact } = require("fast-check-monorepo");11const impact = depthImpact("test5.js", "test5.js");12console.log("impact", impact);13const { depthImpact } = require("fast-check-monorepo");14const impact = depthImpact("test6.js", "test6.js");15console.log("impact", impact);

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