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How to use lazyArb method in fast-check-monorepo

Best JavaScript code snippet using fast-check-monorepo

letrec.ts

Source:letrec.ts

1import { LazyArbitrary } from './_internals/LazyArbitrary';2import { Arbitrary } from '../check/arbitrary/definition/Arbitrary';3import { safeHasOwnProperty } from '../utils/globals';4const safeObjectCreate = Object.create;5/**6 * Type of the value produced by {@link letrec}7 * @remarks Since 3.0.08 * @public9 */10export type LetrecValue<T> = {11  [K in keyof T]: Arbitrary<T[K]>;12};13/**14 * Strongly typed type for the `tie` function passed by {@link letrec} to the `builder` function we pass to it.15 * You may want also want to use its loosely typed version {@link LetrecLooselyTypedTie}.16 *17 * @remarks Since 3.0.018 * @public19 */20export interface LetrecTypedTie<T> {21  <K extends keyof T>(key: K): Arbitrary<T[K]>;22  (key: string): Arbitrary<unknown>;23}24/**25 * Strongly typed type for the `builder` function passed to {@link letrec}.26 * You may want also want to use its loosely typed version {@link LetrecLooselyTypedBuilder}.27 *28 * @remarks Since 3.0.029 * @public30 */31export type LetrecTypedBuilder<T> = (tie: LetrecTypedTie<T>) => LetrecValue<T>;32/**33 * Loosely typed type for the `tie` function passed by {@link letrec} to the `builder` function we pass to it.34 * You may want also want to use its strongly typed version {@link LetrecTypedTie}.35 *36 * @remarks Since 3.0.037 * @public38 */39export type LetrecLooselyTypedTie = (key: string) => Arbitrary<unknown>;40/**41 * Loosely typed type for the `builder` function passed to {@link letrec}.42 * You may want also want to use its strongly typed version {@link LetrecTypedBuilder}.43 *44 * @remarks Since 3.0.045 * @public46 */47export type LetrecLooselyTypedBuilder<T> = (tie: LetrecLooselyTypedTie) => LetrecValue<T>;48/**49 * For mutually recursive types50 *51 * @example52 * ```typescript53 * type Leaf = number;54 * type Node = [Tree, Tree];55 * type Tree = Node | Leaf;56 * const { tree } = fc.letrec<{ tree: Tree, node: Node, leaf: Leaf }>(tie => ({57 *   tree: fc.oneof({depthSize: 'small'}, tie('leaf'), tie('node')),58 *   node: fc.tuple(tie('tree'), tie('tree')),59 *   leaf: fc.nat()60 * }));61 * // tree is 50% of node, 50% of leaf62 * // the ratio goes in favor of leaves as we go deeper in the tree (thanks to depthSize)63 * ```64 *65 * @param builder - Arbitraries builder based on themselves (through `tie`)66 *67 * @remarks Since 1.16.068 * @public69 */70export function letrec<T>(builder: T extends Record<string, unknown> ? LetrecTypedBuilder<T> : never): LetrecValue<T>;71/**72 * For mutually recursive types73 *74 * @example75 * ```typescript76 * const { tree } = fc.letrec(tie => ({77 *   tree: fc.oneof({depthSize: 'small'}, tie('leaf'), tie('node')),78 *   node: fc.tuple(tie('tree'), tie('tree')),79 *   leaf: fc.nat()80 * }));81 * // tree is 50% of node, 50% of leaf82 * // the ratio goes in favor of leaves as we go deeper in the tree (thanks to depthSize)83 * ```84 *85 * @param builder - Arbitraries builder based on themselves (through `tie`)86 *87 * @remarks Since 1.16.088 * @public89 */90export function letrec<T>(builder: LetrecLooselyTypedBuilder<T>): LetrecValue<T>;91// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types92export function letrec<T>(builder: LetrecLooselyTypedBuilder<T> | LetrecTypedBuilder<T>): LetrecValue<T> {93  const lazyArbs: { [K in keyof T]?: LazyArbitrary<unknown> } = safeObjectCreate(null);94  const tie = (key: keyof T): Arbitrary<any> => {95    if (!safeHasOwnProperty(lazyArbs, key)) {96      // Call to hasOwnProperty ensures that the property key will be defined97      lazyArbs[key] = new LazyArbitrary(String(key));98    }99    // eslint-disable-next-line @typescript-eslint/no-non-null-assertion100    return lazyArbs[key]!;101  };102  const strictArbs = builder(tie as any);103  for (const key in strictArbs) {104    if (!safeHasOwnProperty(strictArbs, key)) {105      // Prevents accidental iteration over properties inherited from an objectâs prototype106      continue;107    }108    const lazyAtKey: LazyArbitrary<unknown> | undefined = lazyArbs[key];109    const lazyArb = lazyAtKey !== undefined ? lazyAtKey : new LazyArbitrary(key);110    lazyArb.underlying = strictArbs[key];111    lazyArbs[key] = lazyArb;112  }113  return strictArbs;...

Using AI Code Generation

1const { lazyArb } = require("fast-check");2const arb1 = lazyArb(() => arb2);3const arb2 = lazyArb(() => arb1);4const arb3 = lazyArb(() => arb4);5const arb4 = lazyArb(() => arb3);6const arb5 = lazyArb(() => arb6);7const arb6 = lazyArb(() => arb5);8const { property } = require("fast-check");9const { equal } = require("assert");10property(arb1.arbitrary, (a) => {11  equal(a, "a");12});13property(arb3.arbitrary, (a) => {14  equal(a, "a");15});16property(arb5.arbitrary, (a) => {17  equal(a, "a");18});

Using AI Code Generation

1const fc = require("fast-check");2fc.configureGlobal({3});4fc.assert(5  fc.property(fc.lazyArb(() => fc.string()), fc.lazyArb(() => fc.string()), (a, b) => {6    return a !== b;7  })8);

Using AI Code Generation

1const fc = require('fast-check');2const { lazyArb } = require('fast-check');3const { LazyArbitrary } = require('fast-check/lib/check/arbitrary/LazyArbitrary');4const fc = require('fast-check');5const { lazyArb } = require('fast-check');6const { LazyArbitrary } = require('fast-check/lib/check/arbitrary/LazyArbitrary');7const fc = require('fast-check');8const { lazyArb } = require('fast-check');9const { LazyArbitrary } = require('fast-check/lib/check/arbitrary/LazyArbitrary');10const fc = require('fast-check');11const { lazyArb } = require('fast-check');12const { LazyArbitrary } = require('fast-check/lib/check/arbitrary/LazyArbitrary');13const fc = require('fast-check');14const { lazyArb } = require('fast-check');15const { LazyArbitrary } = require('fast-check/lib/check/arbitrary/LazyArbitrary');16const fc = require('fast-check');17const { lazyArb } = require('fast-check');18const { LazyArbitrary } = require('fast-check/lib/check/arbitrary/LazyArbitrary');19const fc = require('fast-check');20const { lazyArb } = require('fast-check');21const { LazyArbitrary } = require('fast-check/lib/check/arbitrary/LazyArbitrary');22const fc = require('fast-check');23const { lazyArb } = require('fast-check');24const { LazyArbitrary } = require('fast-check/lib/check/arbitrary/LazyArbitrary');25const fc = require('fast-check');26const { lazyArb } = require('fast-check');27const { LazyArbitrary } = require('fast-check/lib/check/arbitrary/LazyArbitrary');

Using AI Code Generation

1const { lazyArb } = require('fast-check-monorepo');2const { array } = require('fast-check');3const { Arbitrary } = require('fast-check');4const arb = lazyArb(() => array(arb));5const arb2 = lazyArb(() => array(arb2));6const arb3 = lazyArb(() => array(arb3));7module.exports = { arb, arb2, arb3 };8const { lazyArb } = require('fast-check-monorepo');9const { array } = require('fast-check');10const { Arbitrary } = require('fast-check');11const arb = lazyArb(() => array(arb));12const arb2 = lazyArb(() => array(arb2));13const arb3 = lazyArb(() => array(arb3));14module.exports = { arb, arb2, arb3 };15const { lazyArb } = require('fast-check-monorepo');16const { array } = require('fast-check');17const { Arbitrary } = require('fast-check');18const arb = lazyArb(() => array(arb));19const arb2 = lazyArb(() => array(arb2));20const arb3 = lazyArb(() => array(arb3));21module.exports = { arb, arb2, arb3 };22const { lazyArb } = require('fast-check-monorepo');23const { array } = require('fast-check');24const { Arbitrary } = require('fast-check');25const arb = lazyArb(() => array(arb));26const arb2 = lazyArb(() => array(arb2));27const arb3 = lazyArb(() => array(arb3));28module.exports = { arb, arb2, arb3 };29const { lazyArb } = require('fast-check-monorepo');30const { array } = require('fast-check');31const { Arbitrary } = require('fast-check');32const arb = lazyArb(() => array(arb));33const arb2 = lazyArb(() => array(arb2));

Using AI Code Generation

1const { lazyArb } = require('fast-check');2const { array } = require('fast-check');3const arbArray = lazyArb(() => array(arbString, { maxLength: 5 }));4const arbString = lazyArb(() => string({ maxLength: 5 }));5const arbNull = lazyArb(() => constant(null));6const arbStringOrNull = lazyArb(() => frequency({ arbitrary: [arbString, arbNull], weight: [4, 1] }));7const arbArrayStringOrNull = lazyArb(() => array(arbStringOrNull, { maxLength: 5, maxNbElements: 2 }));8fc.assert(fc.property(arbArray, (arr) => arr.length === 5));9fc.assert(fc.property(arbArrayStringOrNull, (arr) => arr.filter((e) => e === null).length <= 2));10fc.assert(fc.property(arbArrayStringOrNull, (arr) => arr.length <= 5));11fc.assert(fc.property(arbArrayStringOrNull, (arr) => arr.filter((e) => e.length === 5).length <= 5));12fc.assert(fc.property(arbArrayStringOrNull, (arr) => arr.filter((e) => e.length <= 5).length <= 5));13fc.assert(fc.property(arbArrayStringOrNull, (arr) => arr.filter((e) => e.length <= 5).length <= 4));14fc.assert(fc.property(arbArrayStringOrNull, (arr) => arr.filter((e) => e.length <= 5).length <= 3));

Using AI Code Generation

1const fc = require("fast-check");2const lazyArb = require("fast-check-monorepo").lazyArb;3const myArb = fc.array(fc.string()).chain((arr) => {4    return lazyArb(() => {5        return fc.array(fc.string(), 0, arr.length);6    });7});8fc.assert(9    fc.property(myArb, (arr) => {10        return arr.length <= 5;11    })12);13const fc = require("fast-check");14const lazyArb = require("fast-check-monorepo").lazyArb;15const myArb = fc.array(fc.string()).chain((arr) => {16    return lazyArb(() => {17        return fc.array(fc.string(), 0, arr.length);18    });19});20fc.assert(21    fc.property(myArb, (arr) => {22        return arr.length <= 3;23    })24);25const fc = require("fast-check");26const lazyArb = require("fast-check-monorepo").lazyArb;27const myArb = fc.array(fc.string()).chain((arr) => {28    return lazyArb(() => {29        return fc.array(fc.string(), 0, arr.length);30    });31});32fc.assert(33    fc.property(myArb, (arr) => {

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