From ef06137b65d157abcaaba966a3b13a241f6e7a05 Mon Sep 17 00:00:00 2001
From: DeveloperViraj <workwithvirajjadhav@gmail.com>
Date: Sun, 16 Nov 2025 23:16:02 +0530
Subject: [PATCH] test_runner: add mock-timers support for AbortSignal.timeout

---
 lib/internal/test_runner/mock/mock_timers.js  | 61 +++++++++++++++++--
 .../test-mock-timers-abortsignal-timeout.js   | 26 ++++++++
 2 files changed, 81 insertions(+), 6 deletions(-)
 create mode 100644 test/parallel/test-mock-timers-abortsignal-timeout.js

diff --git a/lib/internal/test_runner/mock/mock_timers.js b/lib/internal/test_runner/mock/mock_timers.js
index 490f8cd06fc549..b6aa5078f3c948 100644
--- a/lib/internal/test_runner/mock/mock_timers.js
+++ b/lib/internal/test_runner/mock/mock_timers.js
@@ -23,6 +23,7 @@ const {
   validateAbortSignal,
   validateNumber,
   validateStringArray,
+  validateUint32,
 } = require('internal/validators');
 
 const {
@@ -34,6 +35,7 @@ const {
 } = require('internal/errors');
 
 const { addAbortListener } = require('internal/events/abort_listener');
+const { AbortController, AbortSignal } = require('internal/abort_controller');
 
 const { TIMEOUT_MAX } = require('internal/timers');
 
@@ -60,9 +62,17 @@ function abortIt(signal) {
 }
 
 /**
- * @enum {('setTimeout'|'setInterval'|'setImmediate'|'Date'|'scheduler.wait')[]} Supported timers
+ * @typedef {('setTimeout'|'setInterval'|'setImmediate'|'Date'|'scheduler.wait'|'AbortSignal.timeout')[]} SupportedApis
+ * Supported timers that can be enabled via MockTimers.enable({ apis: [...] })
  */
-const SUPPORTED_APIS = ['setTimeout', 'setInterval', 'setImmediate', 'Date', 'scheduler.wait'];
+const SUPPORTED_APIS = [
+  'setTimeout',
+  'setInterval',
+  'setImmediate',
+  'Date',
+  'scheduler.wait',
+  'AbortSignal.timeout',
+];
 const TIMERS_DEFAULT_INTERVAL = {
   __proto__: null,
   setImmediate: -1,
@@ -115,6 +125,7 @@ class MockTimers {
   #realPromisifiedSetImmediate;
 
   #nativeDateDescriptor;
+  #realAbortSignalTimeout;
 
   #timersInContext = [];
   #isEnabled = false;
@@ -297,6 +308,18 @@ class MockTimers {
     );
   }
 
+  #storeOriginalAbortSignalTimeout() {
+    this.#realAbortSignalTimeout = ObjectGetOwnPropertyDescriptor(AbortSignal, 'timeout');
+  }
+
+  #restoreOriginalAbortSignalTimeout() {
+    if (this.#realAbortSignalTimeout) {
+      ObjectDefineProperty(AbortSignal, 'timeout', this.#realAbortSignalTimeout);
+    } else {
+      delete AbortSignal.timeout;
+    }
+  }
+
   #createTimer(isInterval, callback, delay, ...args) {
     if (delay > TIMEOUT_MAX) {
       delay = 1;
@@ -604,6 +627,27 @@ class MockTimers {
           this.#nativeDateDescriptor = ObjectGetOwnPropertyDescriptor(globalThis, 'Date');
           globalThis.Date = this.#createDate();
         },
+        'AbortSignal.timeout': () => {
+          this.#storeOriginalAbortSignalTimeout();
+          const mock = this;
+          ObjectDefineProperty(AbortSignal, 'timeout', {
+            __proto__: null,
+            configurable: true,
+            writable: true,
+            value: function value(delay) {
+              validateUint32(delay, 'delay', false);
+              const controller = new AbortController();
+              // Don't keep an unused binding to the timer; mock tick controls it
+              mock.#setTimeout(
+                () => {
+                  controller.abort();
+                },
+                delay,
+              );
+              return controller.signal;
+            },
+          });
+        },
       },
       toReal: {
         '__proto__': null,
@@ -622,6 +666,9 @@ class MockTimers {
         'Date': () => {
           ObjectDefineProperty(globalThis, 'Date', this.#nativeDateDescriptor);
         },
+        'AbortSignal.timeout': () => {
+          this.#restoreOriginalAbortSignalTimeout();
+        },
       },
     };
 
@@ -664,10 +711,12 @@ class MockTimers {
   }
 
   /**
-   * @typedef {{apis: SUPPORTED_APIS;now: number | Date;}} EnableOptions Options to enable the timers
-   * @property {SUPPORTED_APIS} apis List of timers to enable, defaults to all
-   * @property {number | Date} now The epoch to which the timers should be set to, defaults to 0
+   * EnableOptions type:
+   * @typedef {object} EnableOptions
+   * @property {Array<string>} apis List of timers to enable, defaults to all
+   * @property {number|Date} now The epoch to which the timers should be set, defaults to 0
    */
+
   /**
    * Enables the MockTimers replacing the native timers with the fake ones.
    * @param {EnableOptions} [options]
@@ -686,8 +735,8 @@ class MockTimers {
 
     internalOptions.apis ||= SUPPORTED_APIS;
 
-    validateStringArray(internalOptions.apis, 'options.apis');
     // Check that the timers passed are supported
+    validateStringArray(internalOptions.apis, 'options.apis');
     ArrayPrototypeForEach(internalOptions.apis, (timer) => {
       if (!ArrayPrototypeIncludes(SUPPORTED_APIS, timer)) {
         throw new ERR_INVALID_ARG_VALUE(
diff --git a/test/parallel/test-mock-timers-abortsignal-timeout.js b/test/parallel/test-mock-timers-abortsignal-timeout.js
new file mode 100644
index 00000000000000..598855070a39d5
--- /dev/null
+++ b/test/parallel/test-mock-timers-abortsignal-timeout.js
@@ -0,0 +1,26 @@
+'use strict';
+
+// eslint-disable-next-line no-unused-vars
+const common = require('../common');
+const assert = require('assert');
+const { MockTimers } = require('internal/test_runner/mock/mock_timers');
+const { AbortSignal } = require('internal/abort_controller');
+
+{
+  const mock = new MockTimers();
+  mock.enable({ apis: ['AbortSignal.timeout'] });
+
+  try {
+    const signal = AbortSignal.timeout(50);
+
+    assert.strictEqual(signal.aborted, false);
+
+    mock.tick(49);
+    assert.strictEqual(signal.aborted, false);
+
+    mock.tick(1);
+    assert.strictEqual(signal.aborted, true);
+  } finally {
+    mock.reset();
+  }
+}