How to use letrecTree method in fast-check-monorepo

Best JavaScript code snippet using fast-check-monorepo

Poisoning.spec.ts

Source:Poisoning.spec.ts

...108    { name: 'compareBooleanFunc', arbitraryBuilder: () => fc.compareBooleanFunc() },109    { name: 'compareFunc', arbitraryBuilder: () => fc.compareFunc() },110    { name: 'func', arbitraryBuilder: () => fc.func(noop()) },111    // : Recursive structures112    { name: 'letrec', arbitraryBuilder: () => letrecTree() },113    { name: 'memo', arbitraryBuilder: () => memoTree() },114  ])('should not be impacted by altered globals when using $name', ({ arbitraryBuilder }) => {115    // Arrange116    let runId = 0;117    let failedOnce = false;118    const resultStream = fc.sample(fc.infiniteStream(fc.boolean()), { seed, numRuns: 1 })[0];119    const testResult = (): boolean => {120      if (++runId === 100 && !failedOnce) {121        // Force a failure for the 100th execution if we never encountered any before122        // Otherwise it would make fc.assert green as the property never failed123        return false;124      }125      const ret = resultStream.next().value;126      failedOnce = failedOnce || !ret;127      return ret;128    };129    dropMainGlobals();130    // Act131    let interceptedException: unknown = undefined;132    try {133      fc.assert(134        fc.property(arbitraryBuilder(), (_v) => testResult()),135        { seed }136      );137    } catch (err) {138      interceptedException = err;139    }140    // Assert141    restoreGlobals(); // Restore globals before running real checks142    expect(interceptedException).toBeDefined();143    expect(interceptedException).toBeInstanceOf(Error);144    expect((interceptedException as Error).message).toMatch(/Property failed after/);145  });146});147// Helpers148const capturedGlobalThis = globalThis;149const own = Object.getOwnPropertyNames;150function dropAllFromObj(obj: unknown): void {151  for (const k of own(obj)) {152    // We need to keep String for Jest to be able to run properly153    // and Object because of some code generated by TypeScript in the cjs version154    if (obj === capturedGlobalThis && (k === 'String' || k === 'Object')) {155      continue;156    }157    try {158      // eslint-disable-next-line @typescript-eslint/ban-ts-comment159      // @ts-ignore160      delete obj[k];161    } catch (err) {162      // Object.prototype cannot be deleted, and others might too163    }164  }165}166function dropMainGlobals(): void {167  const mainGlobals = [168    Object,169    Function,170    Array,171    Number,172    Boolean,173    String,174    Symbol,175    Date,176    Promise,177    RegExp,178    Error,179    Map,180    BigInt,181    Set,182    WeakMap,183    WeakSet,184    WeakRef,185    FinalizationRegistry,186    Proxy,187    Reflect,188    Buffer,189    ArrayBuffer,190    SharedArrayBuffer,191    Uint8Array,192    Int8Array,193    Uint16Array,194    Int16Array,195    Uint32Array,196    Int32Array,197    Float32Array,198    Float64Array,199    Uint8ClampedArray,200    BigUint64Array,201    BigInt64Array,202    DataView,203    TextEncoder,204    TextDecoder,205    AbortController,206    AbortSignal,207    EventTarget,208    Event,209    MessageChannel,210    MessagePort,211    MessageEvent,212    //URL,213    URLSearchParams,214    JSON,215    Math,216    Intl,217    globalThis,218  ];219  for (const mainGlobal of mainGlobals) {220    if ('prototype' in mainGlobal) {221      dropAllFromObj(mainGlobal.prototype);222    }223    dropAllFromObj(mainGlobal);224  }225}226class NoopArbitrary extends fc.Arbitrary<number> {227  generate(_mrng: fc.Random, _biasFactor: number | undefined): fc.Value<number> {228    return new fc.Value<number>(0, undefined);229  }230  canShrinkWithoutContext(value: unknown): value is number {231    return false;232  }233  shrink(value: number, _context: unknown): fc.Stream<fc.Value<number>> {234    if (value > 5) {235      return fc.Stream.nil();236    }237    return fc.Stream.of(238      new fc.Value<number>(value + 1, undefined), // emulate a shrinker using bare minimal primitives239      new fc.Value<number>(value + 2, undefined),240      new fc.Value<number>(value + 3, undefined)241    );242  }243}244function noop() {245  // Always returns the same value and does not use random number instance.246  // The aim of this arbitrary is to control that we can execute the runner and property even in poisoned context.247  return new NoopArbitrary();248}249class BasicArbitrary extends fc.Arbitrary<number> {250  generate(mrng: fc.Random, _biasFactor: number | undefined): fc.Value<number> {251    return new fc.Value<number>(mrng.nextInt() % 1000, undefined);252  }253  canShrinkWithoutContext(value: unknown): value is number {254    return false;255  }256  shrink(value: number, _context: unknown): fc.Stream<fc.Value<number>> {257    if (value < 10) {258      return fc.Stream.nil();259    }260    return fc.Stream.of(261      new fc.Value<number>((3 * value) / 4, undefined), // emulate a shrinker using bare minimal primitives262      new fc.Value<number>(value / 2, undefined)263    );264  }265}266function basic() {267  // Directly extracting values out of mrng without too many treatments268  return new BasicArbitrary();269}270function mapToConstantEntry(offset: number) {271  return { num: 10, build: (v: number) => v + offset };272}273const CmpSameValueZero = { comparator: 'SameValueZero' as const };274const CmpIsStrictlyEqual = { comparator: 'IsStrictlyEqual' as const };275type Leaf = number;276type Node = { left: Tree; right: Tree };277type Tree = Leaf | Node;278function letrecTree() {279  return fc.letrec((tie) => ({280    tree: fc.oneof(tie('leaf'), tie('node')),281    node: fc.record({ left: tie('tree'), right: tie('tree') }),282    leaf: fc.nat(),283  })).tree;284}285function memoTree() {286  const tree = fc.memo<Tree>((n) => fc.oneof(leaf(), node(n)));287  const node = fc.memo<Node>((n): fc.Arbitrary<Node> => {288    if (n <= 1) return fc.record({ left: leaf(), right: leaf() });289    return fc.record({ left: tree(), right: tree() }); // tree() is equivalent to tree(n-1)290  });291  const leaf: () => fc.Arbitrary<Leaf> = fc.nat;292  return tree(2);...

Tree.ts

Source:Tree.ts

...42    },43  })44const versions = {45  rec: recTree(Gen.bin),46  letrec: letrecTree(Gen.bin).Tree,47}48Utils.record_forEach(versions, (TreeGen, version) => {49  const tap = <A>(a: A) => console.log(JSON.stringify(a, undefined, 2)) || a50  check(version + ' tree join left', TreeGen, (t, p) =>51    p.equals(52      Tree.of(t)53        .chain(t => t)54        .force(),55      t.force()56    )57  )58  check(version + ' tree join right', TreeGen, (t, p) =>59    p.equals(t.chain(j => Tree.of(j)).force(), t.force())60  )...

Using AI Code Generation

1const { letrecTree } = require('fast-check');2const { letrec } = require('fast-check');3const { letrecTuple } = require('fast-check');4const { letrecTupleArray } = require('fast-check');5const { letrecArray } = require('fast-check');6const { letrecObject } = require('fast-check');7const { letrecObjectArray } = require('fast-check');8const { letrecObjectTupleArray } = require('fast-check');9const { letrecObjectTuple } = require('fast-check');10const { letrecObjectArrayTuple } = require('fast-check');11const { letrecObjectArrayTupleArray } = require('fast-check');12const { letrecObjectArrayTupleArrayObject } = require('fast-check');13const { letrecObjectArrayTupleArrayObjectArray } = require('fast-check');14const { letrecObjectArrayTupleArrayObjectTuple } = require('fast-check');15const { letrecObjectArrayTupleArrayObjectTupleArray } = require('fast-check');16const { letrecObjectArrayTupleArrayObjectTupleArrayObject } = require('fast-check');17const { letrecObjectArrayTupleArrayObjectTupleArrayObjectArray } = require('fast-check');18const { letrecObjectArrayTupleArrayObjectTupleArrayObject

Using AI Code Generation

1const { letrecTree } = require('fast-check');2const arb = letrecTree(3  (tie) => ({4    value: tie((t) => t.integer(-100, 100)),5    left: tie((t) => t.option(t)),6    right: tie((t) => t.option(t)),7  }),8  (item) => item9);10console.log(arb.generate());11function letrecTree<T>(builder: (tie: (t: Arbitrary<T>) => Arbitrary<T>) => Arbitrary<T>, unbuilder: (item: T) => T): Arbitrary<T>;12const arb = letrecTree(13  (tie) => ({14    value: tie((t) => t.integer(-100, 100)),15    left: tie((t) => t.option(t)),16    right: tie((t) => t.option(t)),17  }),18  (item) => item19);20{21  "left": {22  },23  "right": {24  }25}26function letrec<T>(builder: (tie: (t: Arbitrary<T>) => Arbitrary<T>) => Arbitrary<T>): Arbitrary<T>;27const arb = letrec((tie) => tie((t) => t.array(t.integer(-100, 100))));

Using AI Code Generation

1const { letrecTree } = require("fast-check");2const arb = letrecTree((tie) => ({3  value: tie("node", { maxDepth: 3 }),4  node: tie("node", { maxDepth: 3 }).map((n) => n + 1),5}));6arb.generate().then((value) => console.log(value));

Using AI Code Generation

1const fc = require('fast-check');2const { letrecTree } = require('fast-check');3const { myFunction } = require('./myFunction');4const { myFunction2 } = require('./myFunction2');5const { myFunction3 } = require('./myFunction3');6const { myFunction4 } = require('./myFunction4');7const { myFunction5 } = require('./myFunction5');8const { myFunction6 } = require('./myFunction6');9const { myFunction7 } = require('./myFunction7');10const { myFunction8 } = require('./myFunction8');11const { myFunction9 } = require('./myFunction9');12const { myFunction10 } = require('./myFunction10');13const { myFunction11 } = require('./myFunction11');14const { myFunction12 } = require('./myFunction12');15const { myFunction13 } = require('./myFunction13');16const { myFunction14 } = require('./myFunction14');17const { myFunction15 } = require('./myFunction15');18const { myFunction16 } = require('./myFunction16');19const { myFunction17 } = require('./myFunction17');20const { myFunction18 } = require('./myFunction18');21const { myFunction19 } = require('./myFunction19');22const { myFunction20 } = require('./myFunction20');23const { myFunction21 } = require('./myFunction21');24const { myFunction22 } = require('./myFunction22');25const { myFunction23 } = require('./myFunction23');26const { myFunction24 } = require('./myFunction24');27const { myFunction25 } = require('./myFunction25');28const { myFunction26 } = require('./myFunction26');29const { myFunction27 } = require('./myFunction27');30const { myFunction28 } = require('./myFunction28');31const { myFunction29 } = require('./myFunction29');32const { myFunction30 } = require('./myFunction30');33const { myFunction31 } = require('./myFunction31');34const { myFunction32 } = require('./myFunction32');35const { myFunction33 } = require('./myFunction33');36const { myFunction34 } = require('./myFunction34');37const { myFunction35 } = require('./myFunction35');38const { myFunction36 } = require('./myFunction36');39const { myFunction37 } = require('./myFunction37

Using AI Code Generation

1const { letrecTree } = require("fast-check");2const { tree } = require("./test2");3const treeArb = letrecTree((tie) => ({4  value: tie(5    tree(6      tie("left"),7      tie("right"),8      tie("value"),9      tie("left"),10      tie("right"),11      tie("value")12}));13treeArb.generate().value;

Using AI Code Generation

1const fc = require("fast-check");2const { letrecTree } = fc;3const { Json } = require("./json");4const { JsonGenerator } = require("./jsonGenerator");5const jsonGenerator = new JsonGenerator();6const arbJson = letrecTree((tie) => ({7  leaf: jsonGenerator.generateJson(),8  branch: fc.tuple(tie("leaf"), tie("leaf")),9  tree: fc.oneof(tie("leaf"), tie("branch")),10}));11fc.assert(12  fc.property(arbJson, (json) => {13    const json2 = Json.parse(JSON.stringify(json));14    return json.equals(json2);15  })16);

Using AI Code Generation

1const { letrecTree } = require("fast-check");2const tree = letrecTree((tie) =>3  tie(4    (t) =>5      t({6        value: t.anything(),7        left: t.option(t),8        right: t.option(t),9      })10);11console.log(tree.generate());

Using AI Code Generation

1const fc = require('fast-check');2const { letrecTree } = require('fast-check');3const arbTree = (maxDepth) => {4  if (maxDepth === 0) {5    return fc.integer();6  } else {7    return fc.oneof(8    );9  }10};11const arbTree2 = letrecTree((tie) => {12  const arbInteger = fc.integer();13  return fc.oneof(arbInteger, fc.tuple(tie('tree'), tie('tree')));14});15fc.assert(16  fc.property(arbTree2(), (t) => {17  })18);19const fc = require('fast-check');20const { letrec } = require('fast-check');21const arbTree = (maxDepth) => {22  if (maxDepth === 0) {23    return fc.integer();24  } else {25    return fc.oneof(26    );27  }28};29const arbTree2 = letrec((tie) => {30  const arbInteger = fc.integer();31  return fc.oneof(arbInteger, fc.tuple(tie('tree'), tie('tree')));32});33fc.assert(34  fc.property(arbTree2(), (t) => {35  })36);37const fc = require('fast-check');38const { letrec } = require('fast-check');39const arbTree = (maxDepth) => {40  if (maxDepth === 0) {41    return fc.integer();42  } else {43    return fc.oneof(

Using AI Code Generation

1const fc = require('fast-check');2const { letrec } = require('fast-check-monorepo');3const Tree = letrec((tie) => fc.oneof(fc.constant(null), fc.tuple(tie, tie).map(([l, r]) => ({ l, r }))));4fc.assert(5  fc.property(Tree, (tree) => {6    return true;7  })8);

Using AI Code Generation

1const fc = require("./index.js");2const letrecTree = fc.letrecTree;3const tree = letrecTree((tie) => ({4  children: fc.array(tie("self"), 0, 5),5  value: fc.integer(0, 100),6}));7fc.assert(8  fc.property(tree(), (t) => {9    return true;10  })11);

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