From 8ed9d1d2ee280a699c0b7122557d40cd2147e887 Mon Sep 17 00:00:00 2001
From: Erick Wendel <erick.workspace@gmail.com>
Date: Thu, 22 Jun 2023 01:01:52 -0300
Subject: [PATCH] test_runner: add initial draft for fakeTimers

Signed-off-by: Erick Wendel <erick.workspace@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/47775
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
---
 doc/api/test.md                              | 528 +++++++++++++++++
 lib/internal/test_runner/{ => mock}/mock.js  |   8 +
 lib/internal/test_runner/mock/mock_timers.js | 336 +++++++++++
 lib/internal/test_runner/test.js             |   2 +-
 lib/test.js                                  |   2 +-
 test/parallel/test-runner-mock-timers.js     | 570 +++++++++++++++++++
 6 files changed, 1444 insertions(+), 2 deletions(-)
 rename lib/internal/test_runner/{ => mock}/mock.js (97%)
 create mode 100644 lib/internal/test_runner/mock/mock_timers.js
 create mode 100644 test/parallel/test-runner-mock-timers.js

diff --git a/doc/api/test.md b/doc/api/test.md
index da7f512d41ef62..6aaae17303872d 100644
--- a/doc/api/test.md
+++ b/doc/api/test.md
@@ -507,6 +507,116 @@ test('spies on an object method', (t) => {
 });
 ```
 
+### Timers
+
+Mocking timers is a technique commonly used in software testing to simulate and
+control the behavior of timers, such as `setInterval` and `setTimeout`,
+without actually waiting for the specified time intervals.
+
+Refer to the [`MockTimers`][] class for a full list of methods and features.
+
+This allows developers to write more reliable and
+predictable tests for time-dependent functionality.
+
+The example below shows how to mock `setTimeout`.
+Using `.enable(['setTimeout']);`
+it will mock the `setTimeout` functions in the [node:timers](./timers.md) and
+[node:timers/promises](./timers.md#timers-promises-api) modules,
+as well as from the Node.js global context.
+
+**Note:** Destructuring functions such as
+`import { setTimeout } from 'node:timers'`
+is currently not supported by this API.
+
+```mjs
+import assert from 'node:assert';
+import { mock, test } from 'node:test';
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', () => {
+  const fn = mock.fn();
+
+  // Optionally choose what to mock
+  mock.timers.enable(['setTimeout']);
+  setTimeout(fn, 9999);
+  assert.strictEqual(fn.mock.callCount(), 0);
+
+  // Advance in time
+  mock.timers.tick(9999);
+  assert.strictEqual(fn.mock.callCount(), 1);
+
+  // Reset the globally tracked mocks.
+  mock.timers.reset();
+
+  // If you call reset mock instance, it will also reset timers instance
+  mock.reset();
+});
+```
+
+```js
+const assert = require('node:assert');
+const { mock, test } = require('node:test');
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', () => {
+  const fn = mock.fn();
+
+  // Optionally choose what to mock
+  mock.timers.enable(['setTimeout']);
+  setTimeout(fn, 9999);
+  assert.strictEqual(fn.mock.callCount(), 0);
+
+  // Advance in time
+  mock.timers.tick(9999);
+  assert.strictEqual(fn.mock.callCount(), 1);
+
+  // Reset the globally tracked mocks.
+  mock.timers.reset();
+
+  // If you call reset mock instance, it'll also reset timers instance
+  mock.reset();
+});
+```
+
+The same mocking functionality is also exposed in the mock property on the [`TestContext`][] object
+of each test. The benefit of mocking via the test context is
+that the test runner will automatically restore all mocked timers
+functionality once the test finishes.
+
+```mjs
+import assert from 'node:assert';
+import { test } from 'node:test';
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', (context) => {
+  const fn = context.mock.fn();
+
+  // Optionally choose what to mock
+  context.mock.timers.enable(['setTimeout']);
+  setTimeout(fn, 9999);
+  assert.strictEqual(fn.mock.callCount(), 0);
+
+  // Advance in time
+  context.mock.timers.tick(9999);
+  assert.strictEqual(fn.mock.callCount(), 1);
+});
+```
+
+```js
+const assert = require('node:assert');
+const { test } = require('node:test');
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', (context) => {
+  const fn = context.mock.fn();
+
+  // Optionally choose what to mock
+  context.mock.timers.enable(['setTimeout']);
+  setTimeout(fn, 9999);
+  assert.strictEqual(fn.mock.callCount(), 0);
+
+  // Advance in time
+  context.mock.timers.tick(9999);
+  assert.strictEqual(fn.mock.callCount(), 1);
+});
+```
+
 ## Test reporters
 
 <!-- YAML
@@ -1346,6 +1456,423 @@ added: v18.13.0
 This function is syntax sugar for [`MockTracker.method`][] with `options.setter`
 set to `true`.
 
+## Class: `MockTimers`
+
+<!-- YAML
+added:
+  - REPLACEME
+-->
+
+> Stability: 1 - Experimental
+
+Mocking timers is a technique commonly used in software testing to simulate and
+control the behavior of timers, such as `setInterval` and `setTimeout`,
+without actually waiting for the specified time intervals.
+
+The [`MockTracker`][] provides a top-level `timers` export
+which is a `MockTimers` instance.
+
+### `timers.enable([timers])`
+
+<!-- YAML
+added:
+  - REPLACEME
+-->
+
+Enables timer mocking for the specified timers.
+
+* `timers` {Array} An optional array containing the timers to mock.
+  The currently supported timer values are `'setInterval'` and `'setTimeout'`.
+  If no array is provided, all timers (`'setInterval'`, `'clearInterval'`, `'setTimeout'`,
+  and `'clearTimeout'`) will be mocked by default.
+
+**Note:** When you enable mocking for a specific timer, its associated
+clear function will also be implicitly mocked.
+
+Example usage:
+
+```mjs
+import { mock } from 'node:test';
+mock.timers.enable(['setInterval']);
+```
+
+```js
+const { mock } = require('node:test');
+mock.timers.enable(['setInterval']);
+```
+
+The above example enables mocking for the `setInterval` timer and
+implicitly mocks the `clearInterval` function. Only the `setInterval`
+and `clearInterval` functions from [node:timers](./timers.md),
+[node:timers/promises](./timers.md#timers-promises-api), and
+`globalThis` will be mocked.
+
+Alternatively, if you call `mock.timers.enable()` without any parameters:
+
+All timers (`'setInterval'`, `'clearInterval'`, `'setTimeout'`, and `'clearTimeout'`)
+will be mocked. The `setInterval`, `clearInterval`, `setTimeout`, and `clearTimeout`
+functions from `node:timers`, `node:timers/promises`,
+and `globalThis` will be mocked.
+
+### `timers.reset()`
+
+<!-- YAML
+added:
+  - REPLACEME
+-->
+
+This function restores the default behavior of all mocks that were previously
+created by this  `MockTimers` instance and disassociates the mocks
+from the  `MockTracker` instance.
+
+**Note:** After each test completes, this function is called on
+the test context's  `MockTracker`.
+
+```mjs
+import { mock } from 'node:test';
+mock.timers.reset();
+```
+
+```js
+const { mock } = require('node:test');
+mock.timers.reset();
+```
+
+### `timers.tick(milliseconds)`
+
+<!-- YAML
+added:
+  - REPLACEME
+-->
+
+Advances time for all mocked timers.
+
+* `milliseconds` {number} The amount of time, in milliseconds,
+  to advance the timers.
+
+**Note:** This diverges from how `setTimeout` in Node.js behaves and accepts
+only positive numbers. In Node.js, `setTimeout` with negative numbers is
+only supported for web compatibility reasons.
+
+The following example mocks a `setTimeout` function and
+by using `.tick` advances in
+time triggering all pending timers.
+
+```mjs
+import assert from 'node:assert';
+import { test } from 'node:test';
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', (context) => {
+  const fn = context.mock.fn();
+
+  context.mock.timers.enable(['setTimeout']);
+
+  setTimeout(fn, 9999);
+
+  assert.strictEqual(fn.mock.callCount(), 0);
+
+  // Advance in time
+  context.mock.timers.tick(9999);
+
+  assert.strictEqual(fn.mock.callCount(), 1);
+});
+```
+
+```js
+const assert = require('node:assert');
+const { test } = require('node:test');
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', (context) => {
+  const fn = context.mock.fn();
+  context.mock.timers.enable(['setTimeout']);
+
+  setTimeout(fn, 9999);
+  assert.strictEqual(fn.mock.callCount(), 0);
+
+  // Advance in time
+  context.mock.timers.tick(9999);
+
+  assert.strictEqual(fn.mock.callCount(), 1);
+});
+```
+
+Alternativelly, the `.tick` function can be called many times
+
+```mjs
+import assert from 'node:assert';
+import { test } from 'node:test';
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', (context) => {
+  const fn = context.mock.fn();
+  context.mock.timers.enable(['setTimeout']);
+  const nineSecs = 9000;
+  setTimeout(fn, nineSecs);
+
+  const twoSeconds = 3000;
+  context.mock.timers.tick(twoSeconds);
+  context.mock.timers.tick(twoSeconds);
+  context.mock.timers.tick(twoSeconds);
+
+  assert.strictEqual(fn.mock.callCount(), 1);
+});
+```
+
+```js
+const assert = require('node:assert');
+const { test } = require('node:test');
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', (context) => {
+  const fn = context.mock.fn();
+  context.mock.timers.enable(['setTimeout']);
+  const nineSecs = 9000;
+  setTimeout(fn, nineSecs);
+
+  const twoSeconds = 3000;
+  context.mock.timers.tick(twoSeconds);
+  context.mock.timers.tick(twoSeconds);
+  context.mock.timers.tick(twoSeconds);
+
+  assert.strictEqual(fn.mock.callCount(), 1);
+});
+```
+
+#### Using clear functions
+
+As mentioned, all clear functions from timers (`clearTimeout` and `clearInterval`)
+are implicity mocked. Take a look at this example using `setTimeout`:
+
+```mjs
+import assert from 'node:assert';
+import { test } from 'node:test';
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', (context) => {
+  const fn = context.mock.fn();
+
+  // Optionally choose what to mock
+  context.mock.timers.enable(['setTimeout']);
+  const id = setTimeout(fn, 9999);
+
+  // Implicity mocked as well
+  clearTimeout(id);
+  context.mock.timers.tick(9999);
+
+  // As that setTimeout was cleared the mock function will never be called
+  assert.strictEqual(fn.mock.callCount(), 0);
+});
+```
+
+```js
+const assert = require('node:assert');
+const { test } = require('node:test');
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', (context) => {
+  const fn = context.mock.fn();
+
+  // Optionally choose what to mock
+  context.mock.timers.enable(['setTimeout']);
+  const id = setTimeout(fn, 9999);
+
+  // Implicity mocked as well
+  clearTimeout(id);
+  context.mock.timers.tick(9999);
+
+  // As that setTimeout was cleared the mock function will never be called
+  assert.strictEqual(fn.mock.callCount(), 0);
+});
+```
+
+#### Working with Node.js timers modules
+
+Once you enable mocking timers, [node:timers](./timers.md),
+[node:timers/promises](./timers.md#timers-promises-api) modules,
+and timers from the Node.js global context are enabled:
+
+**Note:** Destructuring functions such as
+`import { setTimeout } from 'node:timers'` is currently
+not supported by this API.
+
+```mjs
+import assert from 'node:assert';
+import { test } from 'node:test';
+import nodeTimers from 'node:timers';
+import nodeTimersPromises from 'node:timers/promises';
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', async (context) => {
+  const globalTimeoutObjectSpy = context.mock.fn();
+  const nodeTimerSpy = context.mock.fn();
+  const nodeTimerPromiseSpy = context.mock.fn();
+
+  // Optionally choose what to mock
+  context.mock.timers.enable(['setTimeout']);
+  setTimeout(globalTimeoutObjectSpy, 9999);
+  nodeTimers.setTimeout(nodeTimerSpy, 9999);
+
+  const promise = nodeTimersPromises.setTimeout(9999).then(nodeTimerPromiseSpy);
+
+  // Advance in time
+  context.mock.timers.tick(9999);
+  assert.strictEqual(globalTimeoutObjectSpy.mock.callCount(), 1);
+  assert.strictEqual(nodeTimerSpy.mock.callCount(), 1);
+  await promise;
+  assert.strictEqual(nodeTimerPromiseSpy.mock.callCount(), 1);
+});
+```
+
+```js
+const assert = require('node:assert');
+const { test } = require('node:test');
+const nodeTimers = require('node:timers');
+const nodeTimersPromises = require('node:timers/promises');
+
+test('mocks setTimeout to be executed synchronously without having to actually wait for it', async (context) => {
+  const globalTimeoutObjectSpy = context.mock.fn();
+  const nodeTimerSpy = context.mock.fn();
+  const nodeTimerPromiseSpy = context.mock.fn();
+
+  // Optionally choose what to mock
+  context.mock.timers.enable(['setTimeout']);
+  setTimeout(globalTimeoutObjectSpy, 9999);
+  nodeTimers.setTimeout(nodeTimerSpy, 9999);
+
+  const promise = nodeTimersPromises.setTimeout(9999).then(nodeTimerPromiseSpy);
+
+  // Advance in time
+  context.mock.timers.tick(9999);
+  assert.strictEqual(globalTimeoutObjectSpy.mock.callCount(), 1);
+  assert.strictEqual(nodeTimerSpy.mock.callCount(), 1);
+  await promise;
+  assert.strictEqual(nodeTimerPromiseSpy.mock.callCount(), 1);
+});
+```
+
+In Node.js, `setInterval` from [node:timers/promises](./timers.md#timers-promises-api)
+is an `AsyncGenerator` and is also supported by this API:
+
+```mjs
+import assert from 'node:assert';
+import { test } from 'node:test';
+import nodeTimersPromises from 'node:timers/promises';
+test('should tick five times testing a real use case', async (context) => {
+  context.mock.timers.enable(['setInterval']);
+
+  const expectedIterations = 3;
+  const interval = 1000;
+  const startedAt = Date.now();
+  async function run() {
+    const times = [];
+    for await (const time of nodeTimersPromises.setInterval(interval, startedAt)) {
+      times.push(time);
+      if (times.length === expectedIterations) break;
+    }
+    return times;
+  }
+
+  const r = run();
+  context.mock.timers.tick(interval);
+  context.mock.timers.tick(interval);
+  context.mock.timers.tick(interval);
+
+  const timeResults = await r;
+  assert.strictEqual(timeResults.length, expectedIterations);
+  for (let it = 1; it < expectedIterations; it++) {
+    assert.strictEqual(timeResults[it - 1], startedAt + (interval * it));
+  }
+});
+```
+
+```js
+const assert = require('node:assert');
+const { test } = require('node:test');
+const nodeTimersPromises = require('node:timers/promises');
+test('should tick five times testing a real use case', async (context) => {
+  context.mock.timers.enable(['setInterval']);
+
+  const expectedIterations = 3;
+  const interval = 1000;
+  const startedAt = Date.now();
+  async function run() {
+    const times = [];
+    for await (const time of nodeTimersPromises.setInterval(interval, startedAt)) {
+      times.push(time);
+      if (times.length === expectedIterations) break;
+    }
+    return times;
+  }
+
+  const r = run();
+  context.mock.timers.tick(interval);
+  context.mock.timers.tick(interval);
+  context.mock.timers.tick(interval);
+
+  const timeResults = await r;
+  assert.strictEqual(timeResults.length, expectedIterations);
+  for (let it = 1; it < expectedIterations; it++) {
+    assert.strictEqual(timeResults[it - 1], startedAt + (interval * it));
+  }
+});
+```
+
+### `timers.runAll()`
+
+<!-- YAML
+added:
+  - REPLACEME
+-->
+
+Triggers all pending mocked timers immediately.
+
+The example below triggers all pending timers immediately,
+causing them to execute without any delay.
+
+```mjs
+import assert from 'node:assert';
+import { test } from 'node:test';
+
+test('runAll functions following the given order', (context) => {
+  context.mock.timers.enable(['setTimeout']);
+  const results = [];
+  setTimeout(() => results.push(1), 9999);
+
+  // Notice that if both timers have the same timeout,
+  // the order of execution is guaranteed
+  setTimeout(() => results.push(3), 8888);
+  setTimeout(() => results.push(2), 8888);
+
+  assert.deepStrictEqual(results, []);
+
+  context.mock.timers.runAll();
+
+  assert.deepStrictEqual(results, [3, 2, 1]);
+});
+```
+
+```js
+const assert = require('node:assert');
+const { test } = require('node:test');
+
+test('runAll functions following the given order', (context) => {
+  context.mock.timers.enable(['setTimeout']);
+  const results = [];
+  setTimeout(() => results.push(1), 9999);
+
+  // Notice that if both timers have the same timeout,
+  // the order of execution is guaranteed
+  setTimeout(() => results.push(3), 8888);
+  setTimeout(() => results.push(2), 8888);
+
+  assert.deepStrictEqual(results, []);
+
+  context.mock.timers.runAll();
+
+  assert.deepStrictEqual(results, [3, 2, 1]);
+});
+```
+
+**Note:** The `runAll()` function is specifically designed for
+triggering timers in the context of timer mocking.
+It does not have any effect on real-time system
+clocks or actual timers outside of the mocking environment.
+
 ## Class: `TestsStream`
 
 <!-- YAML
@@ -1822,6 +2349,7 @@ added: v18.7.0
 [`--test-reporter`]: cli.md#--test-reporter
 [`--test`]: cli.md#--test
 [`MockFunctionContext`]: #class-mockfunctioncontext
+[`MockTimers`]: #class-mocktimers
 [`MockTracker.method`]: #mockmethodobject-methodname-implementation-options
 [`MockTracker`]: #class-mocktracker
 [`NODE_V8_COVERAGE`]: cli.md#node_v8_coveragedir
diff --git a/lib/internal/test_runner/mock.js b/lib/internal/test_runner/mock/mock.js
similarity index 97%
rename from lib/internal/test_runner/mock.js
rename to lib/internal/test_runner/mock/mock.js
index aa3014a7bc40c6..71363154c88328 100644
--- a/lib/internal/test_runner/mock.js
+++ b/lib/internal/test_runner/mock/mock.js
@@ -26,6 +26,7 @@ const {
   validateInteger,
   validateObject,
 } = require('internal/validators');
+const { MockTimers } = require('internal/test_runner/mock/mock_timers');
 
 function kDefaultFunction() {}
 
@@ -106,6 +107,12 @@ delete MockFunctionContext.prototype.nextImpl;
 
 class MockTracker {
   #mocks = [];
+  #timers;
+
+  get timers() {
+    this.#timers ??= new MockTimers();
+    return this.#timers;
+  }
 
   fn(
     original = function() {},
@@ -265,6 +272,7 @@ class MockTracker {
 
   reset() {
     this.restoreAll();
+    this.#timers?.reset();
     this.#mocks = [];
   }
 
diff --git a/lib/internal/test_runner/mock/mock_timers.js b/lib/internal/test_runner/mock/mock_timers.js
new file mode 100644
index 00000000000000..0af581423fefea
--- /dev/null
+++ b/lib/internal/test_runner/mock/mock_timers.js
@@ -0,0 +1,336 @@
+'use strict';
+
+const {
+  emitExperimentalWarning,
+} = require('internal/util');
+
+const {
+  ArrayPrototypeAt,
+  ArrayPrototypeForEach,
+  ArrayPrototypeIncludes,
+  DateNow,
+  FunctionPrototypeApply,
+  FunctionPrototypeBind,
+  Promise,
+  SymbolAsyncIterator,
+  globalThis,
+} = primordials;
+const {
+  validateAbortSignal,
+  validateArray,
+} = require('internal/validators');
+
+const {
+  AbortError,
+  codes: {
+    ERR_INVALID_STATE,
+    ERR_INVALID_ARG_VALUE,
+  },
+} = require('internal/errors');
+
+const PriorityQueue = require('internal/priority_queue');
+const nodeTimers = require('timers');
+const nodeTimersPromises = require('timers/promises');
+const EventEmitter = require('events');
+
+function compareTimersLists(a, b) {
+  return (a.runAt - b.runAt) || (a.id - b.id);
+}
+
+function setPosition(node, pos) {
+  node.priorityQueuePosition = pos;
+}
+
+function abortIt(signal) {
+  return new AbortError(undefined, { cause: signal.reason });
+}
+
+const SUPPORTED_TIMERS = ['setTimeout', 'setInterval'];
+
+class MockTimers {
+  #realSetTimeout;
+  #realClearTimeout;
+  #realSetInterval;
+  #realClearInterval;
+
+  #realPromisifiedSetTimeout;
+  #realPromisifiedSetInterval;
+
+  #realTimersSetTimeout;
+  #realTimersClearTimeout;
+  #realTimersSetInterval;
+  #realTimersClearInterval;
+
+  #timersInContext = [];
+  #isEnabled = false;
+  #currentTimer = 1;
+  #now = DateNow();
+
+  #executionQueue = new PriorityQueue(compareTimersLists, setPosition);
+
+  #setTimeout = FunctionPrototypeBind(this.#createTimer, this, false);
+  #clearTimeout = FunctionPrototypeBind(this.#clearTimer, this);
+  #setInterval = FunctionPrototypeBind(this.#createTimer, this, true);
+  #clearInterval = FunctionPrototypeBind(this.#clearTimer, this);
+
+  constructor() {
+    emitExperimentalWarning('The MockTimers API');
+  }
+
+  #createTimer(isInterval, callback, delay, ...args) {
+    const timerId = this.#currentTimer++;
+    this.#executionQueue.insert({
+      __proto__: null,
+      id: timerId,
+      callback,
+      runAt: this.#now + delay,
+      interval: isInterval,
+      args,
+    });
+
+    return timerId;
+  }
+
+  #clearTimer(position) {
+    this.#executionQueue.removeAt(position);
+  }
+
+  async * #setIntervalPromisified(interval, startTime, options) {
+    const context = this;
+    const emitter = new EventEmitter();
+    if (options?.signal) {
+      validateAbortSignal(options.signal, 'options.signal');
+
+      if (options.signal?.aborted) {
+        throw abortIt(options.signal);
+      }
+
+      const onAbort = (reason) => {
+        emitter.emit('data', { __proto__: null, aborted: true, reason });
+      };
+
+      options.signal?.addEventListener('abort', onAbort, {
+        __proto__: null,
+        once: true,
+      });
+    }
+
+    const eventIt = EventEmitter.on(emitter, 'data');
+    const callback = () => {
+      startTime += interval;
+      emitter.emit('data', startTime);
+    };
+
+    const timerId = this.#createTimer(true, callback, interval, options);
+    const clearListeners = () => {
+      emitter.removeAllListeners();
+      context.#clearTimer(timerId);
+    };
+    const iterator = {
+      __proto__: null,
+      [SymbolAsyncIterator]() {
+        return this;
+      },
+      async next() {
+        const result = await eventIt.next();
+        const value = ArrayPrototypeAt(result.value, 0);
+        if (value?.aborted) {
+          iterator.return();
+          throw abortIt(options.signal);
+        }
+
+        return {
+          __proto__: null,
+          done: result.done,
+          value,
+        };
+      },
+      async return() {
+        clearListeners();
+        return eventIt.return();
+      },
+    };
+    yield* iterator;
+  }
+
+  #setTimeoutPromisified(ms, result, options) {
+    return new Promise((resolve, reject) => {
+      if (options?.signal) {
+        try {
+          validateAbortSignal(options.signal, 'options.signal');
+        } catch (err) {
+          return reject(err);
+        }
+
+        if (options.signal?.aborted) {
+          return reject(abortIt(options.signal));
+        }
+      }
+
+      const onabort = () => {
+        this.#clearTimeout(id);
+        return reject(abortIt(options.signal));
+      };
+
+      const id = this.#setTimeout(() => {
+        return resolve(result || id);
+      }, ms);
+
+      options?.signal?.addEventListener('abort', onabort, {
+        __proto__: null,
+        once: true,
+      });
+    });
+  }
+
+  #toggleEnableTimers(activate) {
+    const options = {
+      toFake: {
+        setTimeout: () => {
+          this.#realSetTimeout = globalThis.setTimeout;
+          this.#realClearTimeout = globalThis.clearTimeout;
+          this.#realTimersSetTimeout = nodeTimers.setTimeout;
+          this.#realTimersClearTimeout = nodeTimers.clearTimeout;
+          this.#realPromisifiedSetTimeout = nodeTimersPromises.setTimeout;
+
+          globalThis.setTimeout = this.#setTimeout;
+          globalThis.clearTimeout = this.#clearTimeout;
+
+          nodeTimers.setTimeout = this.#setTimeout;
+          nodeTimers.clearTimeout = this.#clearTimeout;
+
+          nodeTimersPromises.setTimeout = FunctionPrototypeBind(
+            this.#setTimeoutPromisified,
+            this,
+          );
+        },
+        setInterval: () => {
+          this.#realSetInterval = globalThis.setInterval;
+          this.#realClearInterval = globalThis.clearInterval;
+          this.#realTimersSetInterval = nodeTimers.setInterval;
+          this.#realTimersClearInterval = nodeTimers.clearInterval;
+          this.#realPromisifiedSetInterval = nodeTimersPromises.setInterval;
+
+          globalThis.setInterval = this.#setInterval;
+          globalThis.clearInterval = this.#clearInterval;
+
+          nodeTimers.setInterval = this.#setInterval;
+          nodeTimers.clearInterval = this.#clearInterval;
+
+          nodeTimersPromises.setInterval = FunctionPrototypeBind(
+            this.#setIntervalPromisified,
+            this,
+          );
+        },
+      },
+      toReal: {
+        setTimeout: () => {
+          globalThis.setTimeout = this.#realSetTimeout;
+          globalThis.clearTimeout = this.#realClearTimeout;
+
+          nodeTimers.setTimeout = this.#realTimersSetTimeout;
+          nodeTimers.clearTimeout = this.#realTimersClearTimeout;
+
+          nodeTimersPromises.setTimeout = this.#realPromisifiedSetTimeout;
+        },
+        setInterval: () => {
+          globalThis.setInterval = this.#realSetInterval;
+          globalThis.clearInterval = this.#realClearInterval;
+
+          nodeTimers.setInterval = this.#realTimersSetInterval;
+          nodeTimers.clearInterval = this.#realTimersClearInterval;
+
+          nodeTimersPromises.setInterval = this.#realPromisifiedSetInterval;
+        },
+      },
+    };
+
+    const target = activate ? options.toFake : options.toReal;
+    ArrayPrototypeForEach(this.#timersInContext, (timer) => target[timer]());
+    this.#isEnabled = activate;
+  }
+
+  tick(time = 1) {
+    if (!this.#isEnabled) {
+      throw new ERR_INVALID_STATE(
+        'You should enable MockTimers first by calling the .enable function',
+      );
+    }
+
+    if (time < 0) {
+      throw new ERR_INVALID_ARG_VALUE(
+        'time',
+        'positive integer',
+        time,
+      );
+    }
+
+    this.#now += time;
+    let timer = this.#executionQueue.peek();
+    while (timer) {
+      if (timer.runAt > this.#now) break;
+      FunctionPrototypeApply(timer.callback, undefined, timer.args);
+
+      this.#executionQueue.shift();
+
+      if (timer.interval) {
+        timer.runAt += timer.interval;
+        this.#executionQueue.insert(timer);
+        return;
+      }
+
+      timer = this.#executionQueue.peek();
+    }
+  }
+
+  enable(timers = SUPPORTED_TIMERS) {
+    if (this.#isEnabled) {
+      throw new ERR_INVALID_STATE(
+        'MockTimers is already enabled!',
+      );
+    }
+
+    validateArray(timers, 'timers');
+
+    // Check that the timers passed are supported
+    ArrayPrototypeForEach(timers, (timer) => {
+      if (!ArrayPrototypeIncludes(SUPPORTED_TIMERS, timer)) {
+        throw new ERR_INVALID_ARG_VALUE(
+          'timers',
+          timer,
+          `option ${timer} is not supported`,
+        );
+      }
+    });
+
+    this.#timersInContext = timers;
+    this.#now = DateNow();
+    this.#toggleEnableTimers(true);
+  }
+
+  reset() {
+    // Ignore if not enabled
+    if (!this.#isEnabled) return;
+
+    this.#toggleEnableTimers(false);
+    this.#timersInContext = [];
+
+    let timer = this.#executionQueue.peek();
+    while (timer) {
+      this.#executionQueue.shift();
+      timer = this.#executionQueue.peek();
+    }
+  }
+
+  runAll() {
+    if (!this.#isEnabled) {
+      throw new ERR_INVALID_STATE(
+        'You should enable MockTimers first by calling the .enable function',
+      );
+    }
+
+    this.tick(Infinity);
+  }
+}
+
+module.exports = { MockTimers };
diff --git a/lib/internal/test_runner/test.js b/lib/internal/test_runner/test.js
index 501fed4addec93..45cbd68fb00824 100644
--- a/lib/internal/test_runner/test.js
+++ b/lib/internal/test_runner/test.js
@@ -31,7 +31,7 @@ const {
   },
   AbortError,
 } = require('internal/errors');
-const { MockTracker } = require('internal/test_runner/mock');
+const { MockTracker } = require('internal/test_runner/mock/mock');
 const { TestsStream } = require('internal/test_runner/tests_stream');
 const {
   createDeferredCallback,
diff --git a/lib/test.js b/lib/test.js
index dc4045622a8284..d096cae23d5357 100644
--- a/lib/test.js
+++ b/lib/test.js
@@ -23,7 +23,7 @@ ObjectDefineProperty(module.exports, 'mock', {
   enumerable: true,
   get() {
     if (lazyMock === undefined) {
-      const { MockTracker } = require('internal/test_runner/mock');
+      const { MockTracker } = require('internal/test_runner/mock/mock');
 
       lazyMock = new MockTracker();
     }
diff --git a/test/parallel/test-runner-mock-timers.js b/test/parallel/test-runner-mock-timers.js
new file mode 100644
index 00000000000000..150883f52237e0
--- /dev/null
+++ b/test/parallel/test-runner-mock-timers.js
@@ -0,0 +1,570 @@
+'use strict';
+process.env.NODE_TEST_KNOWN_GLOBALS = 0;
+const common = require('../common');
+
+const assert = require('node:assert');
+const { it, mock, describe } = require('node:test');
+const nodeTimers = require('node:timers');
+const nodeTimersPromises = require('node:timers/promises');
+
+describe('Mock Timers Test Suite', () => {
+  describe('MockTimers API', () => {
+    it('should throw an error if trying to enable a timer that is not supported', (t) => {
+      assert.throws(() => {
+        t.mock.timers.enable(['DOES_NOT_EXIST']);
+      }, {
+        code: 'ERR_INVALID_ARG_VALUE',
+      });
+    });
+
+    it('should throw an error if trying to enable a timer twice', (t) => {
+      t.mock.timers.enable();
+      assert.throws(() => {
+        t.mock.timers.enable();
+      }, {
+        code: 'ERR_INVALID_STATE',
+      });
+    });
+
+    it('should not throw if calling reset without enabling timers', (t) => {
+      t.mock.timers.reset();
+    });
+
+    it('should throw an error if calling tick without enabling timers', (t) => {
+      assert.throws(() => {
+        t.mock.timers.tick();
+      }, {
+        code: 'ERR_INVALID_STATE',
+      });
+    });
+
+    it('should throw an error if calling tick with a negative number', (t) => {
+      t.mock.timers.enable();
+      assert.throws(() => {
+        t.mock.timers.tick(-1);
+      }, {
+        code: 'ERR_INVALID_ARG_VALUE',
+      });
+    });
+
+    it('should reset all timers when calling .reset function', (t) => {
+      t.mock.timers.enable();
+      const fn = t.mock.fn();
+      global.setTimeout(fn, 1000);
+      t.mock.timers.reset();
+      assert.throws(() => {
+        t.mock.timers.tick(1000);
+      }, {
+        code: 'ERR_INVALID_STATE',
+      });
+
+      assert.strictEqual(fn.mock.callCount(), 0);
+    });
+
+    it('should execute in order if timeout is the same', (t) => {
+      t.mock.timers.enable();
+      const order = [];
+      const fn1 = t.mock.fn(() => order.push('f1'));
+      const fn2 = t.mock.fn(() => order.push('f2'));
+      global.setTimeout(fn1, 1000);
+      global.setTimeout(fn2, 1000);
+      t.mock.timers.tick(1000);
+      assert.strictEqual(fn1.mock.callCount(), 1);
+      assert.strictEqual(fn2.mock.callCount(), 1);
+      assert.deepStrictEqual(order, ['f1', 'f2']);
+    });
+
+    describe('runAll Suite', () => {
+      it('should throw an error if calling runAll without enabling timers', (t) => {
+        assert.throws(() => {
+          t.mock.timers.runAll();
+        }, {
+          code: 'ERR_INVALID_STATE',
+        });
+      });
+
+      it('should trigger all timers when calling .runAll function', async (t) => {
+        const timeoutFn = t.mock.fn();
+        const intervalFn = t.mock.fn();
+
+        t.mock.timers.enable();
+        global.setTimeout(timeoutFn, 1111);
+        const id = global.setInterval(intervalFn, 9999);
+        t.mock.timers.runAll();
+
+        global.clearInterval(id);
+        assert.strictEqual(timeoutFn.mock.callCount(), 1);
+        assert.strictEqual(intervalFn.mock.callCount(), 1);
+      });
+    });
+
+  });
+
+  describe('globals/timers', () => {
+    describe('setTimeout Suite', () => {
+      it('should advance in time and trigger timers when calling the .tick function', (t) => {
+        mock.timers.enable(['setTimeout']);
+
+        const fn = mock.fn();
+
+        global.setTimeout(fn, 4000);
+
+        mock.timers.tick(4000);
+        assert.strictEqual(fn.mock.callCount(), 1);
+        mock.timers.reset();
+      });
+
+      it('should advance in time and trigger timers when calling the .tick function multiple times', (t) => {
+        t.mock.timers.enable(['setTimeout']);
+        const fn = t.mock.fn();
+
+        global.setTimeout(fn, 2000);
+
+        t.mock.timers.tick(1000);
+        assert.strictEqual(fn.mock.callCount(), 0);
+        t.mock.timers.tick(500);
+        assert.strictEqual(fn.mock.callCount(), 0);
+        t.mock.timers.tick(500);
+        assert.strictEqual(fn.mock.callCount(), 1);
+      });
+
+      it('should work with the same params as the original setTimeout', (t) => {
+        t.mock.timers.enable(['setTimeout']);
+        const fn = t.mock.fn();
+        const args = ['a', 'b', 'c'];
+        global.setTimeout(fn, 2000, ...args);
+
+        t.mock.timers.tick(1000);
+        t.mock.timers.tick(500);
+        t.mock.timers.tick(500);
+
+        assert.strictEqual(fn.mock.callCount(), 1);
+        assert.deepStrictEqual(fn.mock.calls[0].arguments, args);
+      });
+
+      it('should keep setTimeout working if timers are disabled', (t, done) => {
+        const now = Date.now();
+        const timeout = 2;
+        const expected = () => now - timeout;
+        global.setTimeout(common.mustCall(() => {
+          assert.strictEqual(now - timeout, expected());
+          done();
+        }), timeout);
+      });
+
+    });
+
+    describe('clearTimeout Suite', () => {
+      it('should not advance in time if clearTimeout was invoked', (t) => {
+        t.mock.timers.enable(['setTimeout']);
+
+        const fn = mock.fn();
+
+        const id = global.setTimeout(fn, 4000);
+        global.clearTimeout(id);
+        t.mock.timers.tick(4000);
+
+        assert.strictEqual(fn.mock.callCount(), 0);
+      });
+    });
+
+    describe('setInterval Suite', () => {
+      it('should tick three times using fake setInterval', (t) => {
+        t.mock.timers.enable(['setInterval']);
+        const fn = t.mock.fn();
+
+        const id = global.setInterval(fn, 200);
+
+        t.mock.timers.tick(200);
+        t.mock.timers.tick(200);
+        t.mock.timers.tick(200);
+
+        global.clearInterval(id);
+
+        assert.strictEqual(fn.mock.callCount(), 3);
+      });
+
+      it('should work with the same params as the original setInterval', (t) => {
+        t.mock.timers.enable(['setInterval']);
+        const fn = t.mock.fn();
+        const args = ['a', 'b', 'c'];
+        const id = global.setInterval(fn, 200, ...args);
+
+        t.mock.timers.tick(200);
+        t.mock.timers.tick(200);
+        t.mock.timers.tick(200);
+
+        global.clearInterval(id);
+
+        assert.strictEqual(fn.mock.callCount(), 3);
+        assert.deepStrictEqual(fn.mock.calls[0].arguments, args);
+        assert.deepStrictEqual(fn.mock.calls[1].arguments, args);
+        assert.deepStrictEqual(fn.mock.calls[2].arguments, args);
+
+      });
+    });
+
+    describe('clearInterval Suite', () => {
+      it('should not advance in time if clearInterval was invoked', (t) => {
+        t.mock.timers.enable(['setInterval']);
+
+        const fn = mock.fn();
+        const id = global.setInterval(fn, 200);
+        global.clearInterval(id);
+        t.mock.timers.tick(200);
+
+        assert.strictEqual(fn.mock.callCount(), 0);
+      });
+    });
+
+  });
+
+  describe('timers Suite', () => {
+    describe('setTimeout Suite', () => {
+      it('should advance in time and trigger timers when calling the .tick function multiple times', (t) => {
+        t.mock.timers.enable(['setTimeout']);
+        const fn = t.mock.fn();
+        const { setTimeout } = nodeTimers;
+        setTimeout(fn, 2000);
+
+        t.mock.timers.tick(1000);
+        t.mock.timers.tick(500);
+        t.mock.timers.tick(500);
+
+        assert.strictEqual(fn.mock.callCount(), 1);
+      });
+
+      it('should work with the same params as the original timers.setTimeout', (t) => {
+        t.mock.timers.enable(['setTimeout']);
+        const fn = t.mock.fn();
+        const { setTimeout } = nodeTimers;
+        const args = ['a', 'b', 'c'];
+        setTimeout(fn, 2000, ...args);
+
+        t.mock.timers.tick(1000);
+        t.mock.timers.tick(500);
+        t.mock.timers.tick(500);
+
+        assert.strictEqual(fn.mock.callCount(), 1);
+        assert.deepStrictEqual(fn.mock.calls[0].arguments, args);
+      });
+    });
+
+    describe('clearTimeout Suite', () => {
+      it('should not advance in time if clearTimeout was invoked', (t) => {
+        t.mock.timers.enable(['setTimeout']);
+
+        const fn = mock.fn();
+        const { setTimeout, clearTimeout } = nodeTimers;
+        const id = setTimeout(fn, 2000);
+        clearTimeout(id);
+        t.mock.timers.tick(2000);
+
+        assert.strictEqual(fn.mock.callCount(), 0);
+      });
+    });
+
+    describe('setInterval Suite', () => {
+      it('should tick three times using fake setInterval', (t) => {
+        t.mock.timers.enable(['setInterval']);
+        const fn = t.mock.fn();
+
+        const id = nodeTimers.setInterval(fn, 200);
+
+        t.mock.timers.tick(200);
+        t.mock.timers.tick(200);
+        t.mock.timers.tick(200);
+        t.mock.timers.tick(200);
+
+        nodeTimers.clearInterval(id);
+
+        assert.strictEqual(fn.mock.callCount(), 4);
+      });
+
+      it('should work with the same params as the original timers.setInterval', (t) => {
+        t.mock.timers.enable(['setInterval']);
+        const fn = t.mock.fn();
+        const args = ['a', 'b', 'c'];
+        const id = nodeTimers.setInterval(fn, 200, ...args);
+
+        t.mock.timers.tick(200);
+        t.mock.timers.tick(200);
+        t.mock.timers.tick(200);
+        t.mock.timers.tick(200);
+
+        nodeTimers.clearInterval(id);
+
+        assert.strictEqual(fn.mock.callCount(), 4);
+        assert.deepStrictEqual(fn.mock.calls[0].arguments, args);
+        assert.deepStrictEqual(fn.mock.calls[1].arguments, args);
+        assert.deepStrictEqual(fn.mock.calls[2].arguments, args);
+        assert.deepStrictEqual(fn.mock.calls[3].arguments, args);
+
+      });
+    });
+
+    describe('clearInterval Suite', () => {
+      it('should not advance in time if clearInterval was invoked', (t) => {
+        t.mock.timers.enable(['setInterval']);
+
+        const fn = mock.fn();
+        const { setInterval, clearInterval } = nodeTimers;
+        const id = setInterval(fn, 200);
+        clearInterval(id);
+        t.mock.timers.tick(200);
+
+        assert.strictEqual(fn.mock.callCount(), 0);
+      });
+    });
+  });
+
+  describe('timers/promises', () => {
+    describe('setTimeout Suite', () => {
+      it('should advance in time and trigger timers when calling the .tick function multiple times', async (t) => {
+        t.mock.timers.enable(['setTimeout']);
+
+        const p = nodeTimersPromises.setTimeout(2000);
+
+        t.mock.timers.tick(1000);
+        t.mock.timers.tick(500);
+        t.mock.timers.tick(500);
+        t.mock.timers.tick(500);
+
+        p.then(common.mustCall((result) => {
+          assert.ok(result);
+        }));
+      });
+
+      it('should work with the same params as the original timers/promises/setTimeout', async (t) => {
+        t.mock.timers.enable(['setTimeout']);
+        const expectedResult = 'result';
+        const controller = new AbortController();
+        const p = nodeTimersPromises.setTimeout(2000, expectedResult, {
+          ref: true,
+          signal: controller.signal
+        });
+
+        t.mock.timers.tick(1000);
+        t.mock.timers.tick(500);
+        t.mock.timers.tick(500);
+        t.mock.timers.tick(500);
+
+        const result = await p;
+        assert.strictEqual(result, expectedResult);
+      });
+
+      it('should abort operation if timers/promises/setTimeout received an aborted signal', async (t) => {
+        t.mock.timers.enable(['setTimeout']);
+        const expectedResult = 'result';
+        const controller = new AbortController();
+        const p = nodeTimersPromises.setTimeout(2000, expectedResult, {
+          ref: true,
+          signal: controller.signal
+        });
+
+        t.mock.timers.tick(1000);
+        controller.abort();
+        t.mock.timers.tick(500);
+        t.mock.timers.tick(500);
+        t.mock.timers.tick(500);
+        await assert.rejects(() => p, {
+          name: 'AbortError',
+        });
+
+      });
+      it('should abort operation even if the .tick wasn\'t called', async (t) => {
+        t.mock.timers.enable(['setTimeout']);
+        const expectedResult = 'result';
+        const controller = new AbortController();
+        const p = nodeTimersPromises.setTimeout(2000, expectedResult, {
+          ref: true,
+          signal: controller.signal
+        });
+
+        controller.abort();
+
+        await assert.rejects(() => p, {
+          name: 'AbortError',
+        });
+
+      });
+
+      it('should abort operation when .abort is called before calling setInterval', async (t) => {
+        t.mock.timers.enable(['setTimeout']);
+        const expectedResult = 'result';
+        const controller = new AbortController();
+        controller.abort();
+        const p = nodeTimersPromises.setTimeout(2000, expectedResult, {
+          ref: true,
+          signal: controller.signal
+        });
+
+        await assert.rejects(() => p, {
+          name: 'AbortError',
+        });
+
+      });
+
+      it('should reject given an an invalid signal instance', async (t) => {
+        t.mock.timers.enable(['setTimeout']);
+        const expectedResult = 'result';
+        const p = nodeTimersPromises.setTimeout(2000, expectedResult, {
+          ref: true,
+          signal: {}
+        });
+
+        await assert.rejects(() => p, {
+          name: 'TypeError',
+          code: 'ERR_INVALID_ARG_TYPE'
+        });
+
+      });
+    });
+
+    describe('setInterval Suite', () => {
+      it('should tick three times using fake setInterval', async (t) => {
+        t.mock.timers.enable(['setInterval']);
+
+        const interval = 100;
+        const intervalIterator = nodeTimersPromises.setInterval(interval, Date.now());
+
+        const first = intervalIterator.next();
+        const second = intervalIterator.next();
+        const third = intervalIterator.next();
+
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+
+        const results = await Promise.all([
+          first,
+          second,
+          third,
+        ]);
+
+        const finished = await intervalIterator.return();
+        assert.deepStrictEqual(finished, { done: true, value: undefined });
+
+        results.forEach((result) => {
+          assert.strictEqual(typeof result.value, 'number');
+          assert.strictEqual(result.done, false);
+        });
+
+      });
+      it('should tick five times testing a real use case', async (t) => {
+
+        t.mock.timers.enable(['setInterval']);
+
+        const expectedIterations = 5;
+        const interval = 1000;
+        const startedAt = Date.now();
+        async function run() {
+          const times = [];
+          for await (const time of nodeTimersPromises.setInterval(interval, startedAt)) {
+            times.push(time);
+            if (times.length === expectedIterations) break;
+
+          }
+          return times;
+        }
+
+        const r = run();
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+
+        const timeResults = await r;
+        assert.strictEqual(timeResults.length, expectedIterations);
+        for (let it = 1; it < expectedIterations; it++) {
+          assert.strictEqual(timeResults[it - 1], startedAt + (interval * it));
+        }
+      });
+
+      it('should abort operation given an abort controller signal', async (t) => {
+        t.mock.timers.enable(['setInterval']);
+
+        const interval = 100;
+        const abortController = new AbortController();
+        const intervalIterator = nodeTimersPromises.setInterval(interval, Date.now(), {
+          signal: abortController.signal
+        });
+
+        const first = intervalIterator.next();
+        const second = intervalIterator.next();
+
+        t.mock.timers.tick(interval);
+        abortController.abort();
+        t.mock.timers.tick(interval);
+
+        const firstResult = await first;
+        // Interval * 2 because value can be a little bit greater than interval
+        assert.ok(firstResult.value < Date.now() + interval * 2);
+        assert.strictEqual(firstResult.done, false);
+
+        await assert.rejects(() => second, {
+          name: 'AbortError',
+        });
+
+      });
+
+      it('should abort operation when .abort is called before calling setInterval', async (t) => {
+        t.mock.timers.enable(['setInterval']);
+
+        const interval = 100;
+        const abortController = new AbortController();
+        abortController.abort();
+        const intervalIterator = nodeTimersPromises.setInterval(interval, Date.now(), {
+          signal: abortController.signal
+        });
+
+        const first = intervalIterator.next();
+        t.mock.timers.tick(interval);
+
+        await assert.rejects(() => first, {
+          name: 'AbortError',
+        });
+      });
+
+      it('should abort operation given an abort controller signal on a real use case', async (t) => {
+        t.mock.timers.enable(['setInterval']);
+        const controller = new AbortController();
+        const signal = controller.signal;
+        const interval = 200;
+        const expectedIterations = 2;
+        const startedAt = Date.now();
+        const timeResults = [];
+        async function run() {
+          const it = nodeTimersPromises.setInterval(interval, startedAt, { signal });
+          for await (const time of it) {
+            timeResults.push(time);
+            if (timeResults.length === 5) break;
+          }
+        }
+
+        const r = run();
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+        controller.abort();
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+        t.mock.timers.tick(interval);
+
+        await assert.rejects(() => r, {
+          name: 'AbortError',
+        });
+        assert.strictEqual(timeResults.length, expectedIterations);
+
+        for (let it = 1; it < expectedIterations; it++) {
+          assert.strictEqual(timeResults[it - 1], startedAt + (interval * it));
+        }
+
+      });
+
+    });
+
+  });
+});