CodeSampleX

Ejemplo

@jest/fake-timers 30.4.1: LegacyFakeTimers

Muestra verificada para npm @jest/fake-timers 30.4.1: LegacyFakeTimers. El contrato se ejecutó en node 22 · linux debian/x64 · docker y pasó.

sha256:b288c253f03432c4c01efa407afd14b9072ca648f6172f46d2eb87a0ba884b5e

Esta red ofrece una sola cosa: una muestra que compila. La ejecutó en un sandbox y guardó el recibo firmado. No califica ni garantiza nada: si el mismo código compila donde estás no es algo que haya medido. Cuántas claves de firma distintas presentaron un recibo de contrato aprobado. Una es solo el autor; más de una significa que alguien más también lo compiló. Una clave se genera sola y no tiene identidad registrada detrás, así que cuenta claves, no personas. MIT-0

Evidencia de ejecución

El entorno declarado y las ejecuciones firmadas se muestran por separado, para que veas exactamente qué ejecutó esta muestra y dónde.

Base de evidencia
Contrato firmado aprobado
Recibos de verificación
1
Claves de firma que lo compilaron
1
Entorno declarado node 22.23 linux 24 · ubuntu · glibc 2.39 x64 node 22.23 javascript npm 10

Entornos de las ejecuciones de verificación

Entorno Contrato Etapas Ejecución
node 22 · linux debian/x64 · docker ed25519:c1973797be207ac4 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · node-typescript@1node:22@sha256:8a34c4ab3ea2…		 2026-09-05

Caso

HOW
Objetivo
verify @jest/fake-timers.LegacyFakeTimers in pkg:npm/%40jest/fake-timers@30.4.1
Paquetes
Símbolos
  • @jest/fake-timers.LegacyFakeTimers
Entorno
node 22.23.2
Creado
2026-09-05T23:53:57Z

Contrato

  1. LegacyFakeTimers instantiates with mock and timer configuration, intercepts timer globals via useFakeTimers, and restores original implementations via useRealTimers
  2. advanceTimersByTime advances virtual clock by milliseconds and executes scheduled timers in chronological order
  3. advanceTimersToNextTimer progresses virtual time directly to the next scheduled timer expiration
  4. runAllTimers exhaustively executes all queued timers, ticks, immediates, and recursively scheduled timers
  5. runOnlyPendingTimers executes currently queued timers without running newly scheduled nested timers
  6. runAllTicks flushes queued microtasks scheduled via process.nextTick
  7. runAllImmediates flushes queued tasks scheduled via setImmediate
  8. clearAllTimers and getTimerCount track and cancel active scheduled timers and immediates
  9. reset and now manage virtual clock time and clear active timers
  10. runWithRealTimers temporarily restores native timer functions during callback execution
  11. dispose clears all timers and marks the fake timer instance as disposed
  12. runWithFakeTimers helper safely executes a scoped callback and restores native timers

Archivos

  • PROMPT.md
  • csx.json
  • index.mjs
  • package-lock.json
  • package.json
  • spec.json
  • test/contract.mjs

Descargar el artefacto de código fuente (tar.gz)

Código fuente

PROMPT.md
Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify @jest/fake-timers.LegacyFakeTimers in pkg:npm/%40jest/fake-timers@30.4.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40jest/fake-timers@30.4.1
Demonstrate these symbols/APIs:
  - @jest/fake-timers.LegacyFakeTimers

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.
csx.json
{"case":{"caseId":"case:sha256:2d573f6e478fa619ba3464a9916936923c2b73204d02fd2f02c072684d65dec2","contract":["LegacyFakeTimers instantiates with mock and timer configuration, intercepts timer globals via useFakeTimers, and restores original implementations via useRealTimers","advanceTimersByTime advances virtual clock by milliseconds and executes scheduled timers in chronological order","advanceTimersToNextTimer progresses virtual time directly to the next scheduled timer expiration","runAllTimers exhaustively executes all queued timers, ticks, immediates, and recursively scheduled timers","runOnlyPendingTimers executes currently queued timers without running newly scheduled nested timers","runAllTicks flushes queued microtasks scheduled via process.nextTick","runAllImmediates flushes queued tasks scheduled via setImmediate","clearAllTimers and getTimerCount track and cancel active scheduled timers and immediates","reset and now manage virtual clock time and clear active timers","runWithRealTimers temporarily restores native timer functions during callback execution","dispose clears all timers and marks the fake timer instance as disposed","runWithFakeTimers helper safely executes a scoped callback and restores native timers"],"goal":"verify @jest/fake-timers.LegacyFakeTimers in pkg:npm/%40jest/fake-timers@30.4.1","kind":"HOW","packages":["pkg:npm/%40jest/fake-timers@30.4.1"],"schemaVersion":1,"symbols":["@jest/fake-timers.LegacyFakeTimers"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","executionContext":"node","language":"javascript","libc":"glibc","libcVersion":"2.39","moduleSystem":"cjs","os":"linux","osVersionBucket":"24","packageManager":"npm","packageManagerVersion":"10.9.8","runtime":"node","runtimeVersion":"22.23.2","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/%40jest/fake-timers@30.4.1"],"schemaVersion":1,"subject":"pkg:npm/%40jest/fake-timers@30.4.1","symbols":["@jest/fake-timers.LegacyFakeTimers"],"verifierAdapter":"node-typescript@1"}
index.mjs
import { LegacyFakeTimers } from '@jest/fake-timers';

export { LegacyFakeTimers };

export function createLegacyFakeTimers(options = {}) {
  const {
    global = globalThis,
    moduleMocker = {
      fn: (impl) => {
        const fn = (...args) => impl(...args);
        return fn;
      }
    },
    timerConfig = {
      idToRef: (id) => id,
      refToId: (ref) => ref
    },
    config = { rootDir: process.cwd() },
    maxLoops
  } = options;

  return new LegacyFakeTimers({
    global,
    moduleMocker,
    timerConfig,
    config,
    maxLoops
  });
}

export function runWithFakeTimers(fn, options = {}) {
  const fakeTimers = createLegacyFakeTimers(options);
  fakeTimers.useFakeTimers();
  try {
    return fn(fakeTimers);
  } finally {
    fakeTimers.useRealTimers();
  }
}
package-lock.json
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package.json
{
  "name": "sample-jest-legacy-fake-timers",
  "version": "1.0.0",
  "description": "Clean-room verification sample for @jest/fake-timers LegacyFakeTimers",
  "type": "module",
  "main": "index.mjs",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "@jest/fake-timers": "30.4.1"
  }
}
spec.json
{
  "schemaVersion": 1,
  "goal": "verify @jest/fake-timers.LegacyFakeTimers in pkg:npm/%40jest/fake-timers@30.4.1",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40jest/fake-timers@30.4.1"
  ],
  "symbols": [
    "@jest/fake-timers.LegacyFakeTimers"
  ]
}
test/contract.mjs
import assert from 'node:assert/strict';
import { LegacyFakeTimers } from '@jest/fake-timers';
import { createLegacyFakeTimers, runWithFakeTimers } from '../index.mjs';

// 1. LegacyFakeTimers instantiates with mock and timer configuration, intercepts timer globals via useFakeTimers, and restores original implementations via useRealTimers
{
  const originalSetTimeout = globalThis.setTimeout;
  const originalClearTimeout = globalThis.clearTimeout;
  const originalSetInterval = globalThis.setInterval;
  const originalClearInterval = globalThis.clearInterval;

  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  assert.notEqual(globalThis.setTimeout, originalSetTimeout);
  assert.notEqual(globalThis.clearTimeout, originalClearTimeout);
  assert.notEqual(globalThis.setInterval, originalSetInterval);
  assert.notEqual(globalThis.clearInterval, originalClearInterval);

  timers.useRealTimers();

  assert.equal(globalThis.setTimeout, originalSetTimeout);
  assert.equal(globalThis.clearTimeout, originalClearTimeout);
  assert.equal(globalThis.setInterval, originalSetInterval);
  assert.equal(globalThis.clearInterval, originalClearInterval);
}

// 2. advanceTimersByTime advances virtual clock by milliseconds and executes scheduled timers in chronological order
{
  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  const executionOrder = [];
  setTimeout(() => { executionOrder.push('first'); }, 100);
  setTimeout(() => { executionOrder.push('second'); }, 200);

  timers.advanceTimersByTime(50);
  assert.deepEqual(executionOrder, []);
  assert.equal(timers.now(), 50);

  timers.advanceTimersByTime(50);
  assert.deepEqual(executionOrder, ['first']);
  assert.equal(timers.now(), 100);

  timers.advanceTimersByTime(100);
  assert.deepEqual(executionOrder, ['first', 'second']);
  assert.equal(timers.now(), 200);

  timers.useRealTimers();
}

// 3. advanceTimersToNextTimer progresses virtual time directly to the next scheduled timer expiration
{
  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  const results = [];
  setTimeout(() => { results.push(1); }, 150);
  setTimeout(() => { results.push(2); }, 300);

  timers.advanceTimersToNextTimer();
  assert.deepEqual(results, [1]);
  assert.equal(timers.now(), 150);

  timers.advanceTimersToNextTimer();
  assert.deepEqual(results, [1, 2]);
  assert.equal(timers.now(), 300);

  timers.useRealTimers();
}

// 4. runAllTimers exhaustively executes all queued timers, ticks, immediates, and recursively scheduled timers
{
  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  const sequence = [];
  setTimeout(() => {
    sequence.push('root');
    setTimeout(() => {
      sequence.push('nested');
    }, 50);
  }, 100);

  timers.runAllTimers();
  assert.deepEqual(sequence, ['root', 'nested']);
  assert.equal(timers.getTimerCount(), 0);

  timers.useRealTimers();
}

// 5. runOnlyPendingTimers executes currently queued timers without running newly scheduled nested timers
{
  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  const items = [];
  setTimeout(() => {
    items.push('initial');
    setTimeout(() => {
      items.push('child');
    }, 50);
  }, 100);

  timers.runOnlyPendingTimers();
  assert.deepEqual(items, ['initial']);
  assert.equal(timers.getTimerCount(), 1);

  timers.clearAllTimers();
  assert.equal(timers.getTimerCount(), 0);
  timers.useRealTimers();
}

// 6. runAllTicks flushes queued microtasks scheduled via process.nextTick
{
  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  const ticks = [];
  process.nextTick(() => { ticks.push('t1'); });
  process.nextTick(() => { ticks.push('t2'); });

  timers.runAllTicks();
  assert.deepEqual(ticks, ['t1', 't2']);

  timers.useRealTimers();
}

// 7. runAllImmediates flushes queued tasks scheduled via setImmediate
{
  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  const immediates = [];
  setImmediate(() => { immediates.push('imm1'); });
  setImmediate(() => { immediates.push('imm2'); });

  timers.runAllImmediates();
  assert.deepEqual(immediates, ['imm1', 'imm2']);

  timers.useRealTimers();
}

// 8. clearAllTimers and getTimerCount track and cancel active scheduled timers and immediates
{
  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  const timer1 = setTimeout(() => {}, 100);
  const timer2 = setInterval(() => {}, 200);
  setImmediate(() => {});

  assert.equal(timers.getTimerCount(), 3);
  clearTimeout(timer1);
  assert.equal(timers.getTimerCount(), 2);

  timers.clearAllTimers();
  assert.equal(timers.getTimerCount(), 0);

  timers.useRealTimers();
}

// 9. reset and now manage virtual clock time and clear active timers
{
  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  setTimeout(() => {}, 500);
  timers.advanceTimersByTime(500);
  assert.equal(timers.now(), 500);

  timers.reset();
  assert.equal(timers.now(), 0);
  assert.equal(timers.getTimerCount(), 0);

  timers.useRealTimers();
}

// 10. runWithRealTimers temporarily restores native timer functions during callback execution
{
  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  const fakeSetTimeout = globalThis.setTimeout;
  let executed = false;

  timers.runWithRealTimers(() => {
    assert.notEqual(globalThis.setTimeout, fakeSetTimeout);
    executed = true;
  });

  assert.equal(executed, true);
  assert.equal(globalThis.setTimeout, fakeSetTimeout);

  timers.useRealTimers();
}

// 11. dispose clears all timers and marks the fake timer instance as disposed
{
  const timers = createLegacyFakeTimers();
  timers.useFakeTimers();

  setTimeout(() => {}, 100);
  assert.equal(timers.getTimerCount(), 1);

  timers.dispose();
  assert.equal(timers.getTimerCount(), 0);

  timers.useRealTimers();
}

// 12. runWithFakeTimers helper safely executes a scoped callback and restores native timers
{
  const originalSetTimeout = globalThis.setTimeout;
  let callbackRan = false;

  runWithFakeTimers(fakeTimers => {
    assert.notEqual(globalThis.setTimeout, originalSetTimeout);
    setTimeout(() => { callbackRan = true; }, 100);
    fakeTimers.runAllTimers();
    assert.equal(callbackRan, true);
  });

  assert.equal(globalThis.setTimeout, originalSetTimeout);
}

console.log('All @jest/fake-timers.LegacyFakeTimers contract assertions passed.');

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