Add clearTimeout to Timer and MockTimer

test/unit/mock-timer.js

@@ -0,0 +1,89 @@
+const test = require('tap').test;
+const MockTimer = require('../fixtures/mock-timer');
+
+test('spec', t => {
+    const timer = new MockTimer();
+
+    t.type(MockTimer, 'function');
+    t.type(timer, 'object');
+
+    // Most members of MockTimer mimic members of Timer.
+    t.type(timer.startTime, 'number');
+    t.type(timer.time, 'function');
+    t.type(timer.start, 'function');
+    t.type(timer.timeElapsed, 'function');
+    t.type(timer.setTimeout, 'function');
+    t.type(timer.clearTimeout, 'function');
+
+    // A few members of MockTimer have no Timer equivalent and should only be used in tests.
+    t.type(timer.hasTimeouts, 'function');
+
+    t.end();
+});
+
+test('time', t => {
+    const timer = new MockTimer();
+    const delta = 1;
+
+    const time1 = timer.time();
+    const time2 = timer.time();
+    timer.advanceMockTime(delta);
+    const time3 = timer.time();
+
+    t.equal(time1, time2);
+    t.equal(time2 + delta, time3);
+    t.end();
+});
+
+test('start / timeElapsed', t => new Promise(resolve => {
+    const timer = new MockTimer();
+    const halfDelay = 1;
+    const fullDelay = halfDelay + halfDelay;
+
+    timer.start();
+
+    let timeoutCalled = 0;
+
+    // Wait and measure timer
+    timer.setTimeout(() => {
+        t.equal(timeoutCalled, 0);
+        ++timeoutCalled;
+
+        const timeElapsed = timer.timeElapsed();
+        t.equal(timeElapsed, fullDelay);
+        t.end();
+
+        resolve();
+    }, fullDelay);
+
+    // this should not trigger the callback
+    timer.advanceMockTime(halfDelay);
+
+    // give the mock timer a chance to run tasks
+    global.setTimeout(() => {
+        // we've only mock-waited for half the delay so it should not have run yet
+        t.equal(timeoutCalled, 0);
+
+        // this should trigger the callback
+        timer.advanceMockTime(halfDelay);
+    }, 0);
+}));
+
+test('clearTimeout / hasTimeouts', t => new Promise((resolve, reject) => {
+    const timer = new MockTimer();
+
+    const timeoutId = timer.setTimeout(() => {
+        reject(new Error('Canceled task ran'));
+    }, 1);
+
+    timer.setTimeout(() => {
+        resolve('Non-canceled task ran');
+        t.end();
+    }, 2);
+
+    timer.clearTimeout(timeoutId);
+
+    while (timer.hasTimeouts()) {
+        timer.advanceMockTime(1);
+    }
+}));