Jasmine cheat sheet - mocking the clock

Demonstrating jasmine clock faking functionality

HTML

<script src="http://jasmine.github.io/1.3/lib/jasmine.js"></script>
<script src="http://jasmine.github.io/1.3/lib/jasmine-html.js"></script>
<link rel="stylesheet" href="http://jasmine.github.io/1.3/lib/jasmine.css">

JavaScript

describe("Manually ticking the Jasmine Mock Clock", function () {
    var timerCallback;

    beforeEach(function () {
        timerCallback = jasmine.createSpy('timerCallback');
        jasmine.Clock.useMock();
    });

    it("causes a timeout to be called synchronously", function () {
        setTimeout(function () {
            timerCallback();
        }, 100);

        expect(timerCallback).not.toHaveBeenCalled();
        
        // Advance the clock manually
        jasmine.Clock.tick(101);

        expect(timerCallback).toHaveBeenCalled();
    });

    it("causes an interval to be called synchronously", function () {
        setInterval(function () {
            timerCallback();
        }, 100);

        expect(timerCallback).not.toHaveBeenCalled();

        jasmine.Clock.tick(101);
        expect(timerCallback.callCount).toEqual(1);

        jasmine.Clock.tick(50);
        expect(timerCallback.callCount).toEqual(1);

        jasmine.Clock.tick(50);
        expect(timerCallback.callCount).toEqual(2);
    });
    
    it("can clear an interval", function () {
        var id = setInterval(function () {
            timerCallback();
        }, 100);

        expect(timerCallback).not.toHaveBeenCalled();

        jasmine.Clock.tick(101);
        expect(timerCallback.callCount).toEqual(1);

        jasmine.Clock.tick(50);
        expect(timerCallback.callCount).toEqual(1);

        jasmine.Clock.tick(50);
        expect(timerCallback.callCount).toEqual(2);
        
        clearInterval(id);
        jasmine.Clock.tick(101);
        expect(timerCallback.callCount).toEqual(2);
    });
});

// Jasmine spec runner
(function () {
    var jasmineEnv = jasmine.getEnv();
    jasmineEnv.updateInterval = 1000;

    var trivialReporter = new jasmine.TrivialReporter();

    jasmineEnv.addReporter(trivialReporter);

    jasmineEnv.specFilter = function (spec) {
        return trivialReporter.specFilter(spec);
    };

    var currentWindowOnload = window.onload;

   ...