@sinonjs/fake-timers 10.3.0: install and advance timers using FakeTimers clock

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: install and advance timers using FakeTimers clock
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40sinonjs/fake-timers@10.3.0
Demonstrate these symbols/APIs:
  - Clock.tick
  - Clock.uninstall
  - install

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.

{"case":{"caseId":"case:sha256:ed62146403969e3d88d7669a0d5040adaddcd3ba3f7c3a34e5d9420e202a9ac4","contract":["FakeTimers.install replaces global timer functions and initializes now to the configured timestamp","clock.tick advances time and triggers scheduled setTimeout callbacks synchronously","clock.tick handles repeating setInterval callbacks and stops after clearInterval","clock.runAll executes all scheduled timers until the queue is empty","clock.setSystemTime adjusts current clock time without executing intermediate scheduled timers","FakeTimers.createClock creates an isolated clock instance without mutating globals","clock.uninstall restores all overridden globals cleanly"],"goal":"install and advance timers using FakeTimers clock","kind":"HOW","packages":["pkg:npm/%40sinonjs/fake-timers@10.3.0"],"schemaVersion":1,"symbols":["Clock.tick","Clock.uninstall","install"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"npm","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/%40sinonjs/fake-timers@10.3.0"],"schemaVersion":1,"subject":"pkg:npm/%40sinonjs/fake-timers@10.3.0","symbols":["Clock.tick","Clock.uninstall","install"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-fake-timers",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-fake-timers",
      "version": "1.0.0",
      "dependencies": {
        "@sinonjs/fake-timers": "10.3.0"
      }
    },
    "node_modules/@sinonjs/commons": {
      "version": "3.0.1",
      "resolved": "https://registry.npmjs.org/@sinonjs/commons/-/commons-3.0.1.tgz",
      "integrity": "sha512-K3mCHKQ9sVh8o1C9cxkwxaOmXoAMlDxC1mYyHrjqOWEcBjYr76t96zL2zlj5dUGZ3HSw240X1qgH3Mjf1yJWpQ==",
      "license": "BSD-3-Clause",
      "dependencies": {
        "type-detect": "4.0.8"
      }
    },
    "node_modules/@sinonjs/fake-timers": {
      "version": "10.3.0",
      "resolved": "https://registry.npmjs.org/@sinonjs/fake-timers/-/fake-timers-10.3.0.tgz",
      "integrity": "sha512-V4BG07kuYSUkTCSBHG8G8TNhM+F19jXFWnQtzj+we8DrkpSBCee9Z3Ms8yiGer/dlmhe35/Xdgyo3/0rQKg7YA==",
      "license": "BSD-3-Clause",
      "dependencies": {
        "@sinonjs/commons": "^3.0.0"
      }
    },
    "node_modules/type-detect": {
      "version": "4.0.8",
      "resolved": "https://registry.npmjs.org/type-detect/-/type-detect-4.0.8.tgz",
      "integrity": "sha512-0fr/mIH1dlO+x7TlcMy+bIDqKPsw/70tVyeHW787goQjhmqaZe10uwLujubK9q9Lg6Fiho1KUKDYz0Z7k7g5/g==",
      "license": "MIT",
      "engines": {
        "node": ">=4"
      }
    }
  }
}

{
  "name": "sample-fake-timers",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "dependencies": {
    "@sinonjs/fake-timers": "10.3.0"
  }
}

{
  "schemaVersion": 1,
  "goal": "install and advance timers using FakeTimers clock",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40sinonjs/fake-timers@10.3.0"
  ],
  "symbols": [
    "Clock.tick",
    "Clock.uninstall",
    "install"
  ]
}

import assert from 'node:assert/strict';
import FakeTimers from '@sinonjs/fake-timers';

// 1. FakeTimers.install replaces global timer functions and initializes now to the configured timestamp
{
  const initialTime = 1600000000000;
  const originalSetTimeout = globalThis.setTimeout;
  const clock = FakeTimers.install({ now: initialTime, toFake: ['setTimeout', 'clearTimeout', 'Date'] });

  assert.notEqual(globalThis.setTimeout, originalSetTimeout);
  assert.equal(Date.now(), initialTime);
  assert.equal(clock.now, initialTime);

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

// 2. clock.tick advances time and triggers scheduled setTimeout callbacks synchronously
{
  const clock = FakeTimers.install();
  let called = false;
  let callTime = 0;

  setTimeout(() => {
    called = true;
    callTime = clock.now;
  }, 150);

  clock.tick(100);
  assert.equal(called, false);
  assert.equal(clock.now, 100);

  clock.tick(50);
  assert.equal(called, true);
  assert.equal(callTime, 150);
  assert.equal(clock.now, 150);

  clock.uninstall();
}

// 3. clock.tick handles repeating setInterval callbacks and stops after clearInterval
{
  const clock = FakeTimers.install();
  let count = 0;

  const intervalId = setInterval(() => {
    count++;
  }, 50);

  clock.tick(150);
  assert.equal(count, 3);

  clearInterval(intervalId);
  clock.tick(100);
  assert.equal(count, 3);

  clock.uninstall();
}

// 4. clock.runAll executes all scheduled timers until the queue is empty
{
  const clock = FakeTimers.install();
  const order = [];

  setTimeout(() => order.push('second'), 200);
  setTimeout(() => order.push('first'), 100);

  clock.runAll();
  assert.deepEqual(order, ['first', 'second']);
  assert.equal(clock.now, 200);

  clock.uninstall();
}

// 5. clock.setSystemTime adjusts current clock time without executing intermediate scheduled timers
{
  const clock = FakeTimers.install({ now: 1000 });
  let called = false;

  setTimeout(() => {
    called = true;
  }, 500);

  clock.setSystemTime(2000);
  assert.equal(clock.now, 2000);
  assert.equal(called, false);

  clock.tick(500);
  assert.equal(called, true);

  clock.uninstall();
}

// 6. FakeTimers.createClock creates an isolated clock instance without mutating globals
{
  const originalSetTimeout = globalThis.setTimeout;
  const clock = FakeTimers.createClock(500);

  assert.equal(globalThis.setTimeout, originalSetTimeout);
  assert.equal(clock.now, 500);

  let executed = false;
  clock.setTimeout(() => {
    executed = true;
  }, 100);

  clock.tick(100);
  assert.equal(executed, true);
  assert.equal(clock.now, 600);
}

// 7. clock.uninstall restores all overridden globals cleanly
{
  const originalDate = globalThis.Date;
  const originalClearTimeout = globalThis.clearTimeout;
  const clock = FakeTimers.install();

  assert.notEqual(globalThis.Date, originalDate);
  assert.notEqual(globalThis.clearTimeout, originalClearTimeout);

  clock.uninstall();
  assert.equal(globalThis.Date, originalDate);
  assert.equal(globalThis.clearTimeout, originalClearTimeout);
}