test_runner: add ref methods to mocked timers

Fixes: #51701

lib/internal/test_runner/mock/mock_timers.js

@@ -67,6 +67,32 @@ const TIMERS_DEFAULT_INTERVAL = {
   setImmediate: -1,
 };
 
+class Timeout {
+  constructor(opts) {
+    this.id = opts.id;
+    this.callback = opts.callback;
+    this.runAt = opts.runAt;
+    this.interval = opts.interval;
+    this.args = opts.args;
+  }
+
+  hasRef() {
+    return true;
+  }
+
+  ref() {
+    return this;
+  }
+
+  unref() {
+    return this;
+  }
+
+  refresh() {
+    return this;
+  }
+}
+
 class MockTimers {
   #realSetTimeout;
   #realClearTimeout;
@@ -260,14 +286,16 @@ class MockTimers {
 
   #createTimer(isInterval, callback, delay, ...args) {
     const timerId = this.#currentTimer++;
-    const timer = {
+    const opts = {
       __proto__: null,
       id: timerId,
       callback,
       runAt: this.#now + delay,
       interval: isInterval ? delay : undefined,
       args,
     };
+
+    const timer = new Timeout(opts);
     this.#executionQueue.insert(timer);
     return timer;
   }

test/parallel/test-runner-mock-timers.js

@@ -844,4 +844,38 @@ describe('Mock Timers Test Suite', () => {
       clearTimeout(id);
     });
   });
+
+  describe('Api should have same public properties as original', () => {
+    it('should have hasRef', (t) => {
+      t.mock.timers.enable();
+      const timer = setTimeout();
+      assert.strictEqual(typeof timer.hasRef, 'function');
+      assert.strictEqual(timer.hasRef(), true);
+      clearTimeout(timer);
+    });
+
+    it('should have ref', (t) => {
+      t.mock.timers.enable();
+      const timer = setTimeout();
+      assert.ok(typeof timer.ref === 'function');
+      assert.deepStrictEqual(timer.ref(), timer);
+      clearTimeout(timer);
+    });
+
+    it('should have unref', (t) => {
+      t.mock.timers.enable();
+      const timer = setTimeout();
+      assert.ok(typeof timer.unref === 'function');
+      assert.deepStrictEqual(timer.unref(), timer);
+      clearTimeout(timer);
+    });
+
+    it('should have refresh', (t) => {
+      t.mock.timers.enable();
+      const timer = setTimeout();
+      assert.ok(typeof timer.refresh === 'function');
+      assert.deepStrictEqual(timer.refresh(), timer);
+      clearTimeout(timer);
+    });
+  });
 });