Angular 2 attribute directive - inputs are undefined

Question

I'm trying to create an attribute directive that will catch click events and report them to our reporting service. I've followed the attribute directives guide and ended up with this:

@Directive({
    selector: '[mtTrack]'
})
export class MtTrackDirective {

    private _eventData: any;

    constructor(private trackingService: TrackingService) {}

    @Input('mtTrack') eventName: string;

    @Input('mtTrackEvent') set mtTrackEvent(data: any) {
        this._eventData = data;
    }

    @HostListener('click') onClick() {
        this.trackingService.track(this.eventName, this._eventData)
    }
}

I then try to test it with this test:

describe('MatificTrackDirective', () => {
    @Component({
        selector: 'test-cmp',
        template: `<div [mtTrack]="'fakeEvent'" [mtTrackEvent]="{test: 'fake data'}"></div>`,
        viewProviders: [MatificTrackDirective]
    })
    class TestComponent {}

    let trackingMock;
    let fixture: ComponentFixture<TestComponent>;
    let debugElement : DebugElement;
    let hostComp;

    beforeEach(() => {
        TestBed.configureTestingModule({
            declarations: [TestComponent, MatificTrackDirective],
            providers: [{provide: TrackingService, useValue: mockClass(TrackingService)}]
        }).compileComponents();
        fixture = TestBed.createComponent(TestComponent);
        hostComp = fixture.componentInstance;
        debugElement = fixture.debugElement.query(By.directive(MatificTrackDirective));
        trackingMock = debugElement.injector.get(TrackingService)
    })
    describe("HANDLERS", () => {
        describe("onclick", () => {
            When(() => {
                debugElement.triggerEventHandler('click', {});
                fixture.detectChanges();
            });
            Then(() => expect(trackingMock.track).toHaveBeenCalledWith('fakeEvent', {test: 'fake data'}));
        });
    });
});

But my trackingMock is being called with [undefined, undefined] instead of the values in the template. Any idea what is wrong?

I'm using Angular 2.2.1.