Angular 2 Observable testing Error: Cannot use setInterval from within an async zone test - unit-testing

Question

I'm trying to test a component, which uses a service that makes async http calls. The service returns an Observable, which the component subscribes on.
Service code snippet:
getRecentMachineTemperatures(_machine_Id): Observable<IDeviceReadings[]> {
return this.http.get(TemperatureService.URL + _machine_Id)
.map(response => { return response.json(); })
.map((records: Array<any>) => {
let result = new Array<IDeviceReadings>();
if (records) {
records.forEach((record) => {
let device = new IDeviceReadings();
device.device_id = record.device_id;
if (record.d) {
record.d.forEach((t) => {
let temperature = new ITemperature();
temperature.timestamp = t.timestamp;
temperature.value = t.temperature;
device.temperatures.push(temperature);
});
}
result.push(device);
});
}
return result;
});
}
Component code snippet:
ngOnInit() {
this.getRecentTemperatures();
}
getRecentTemperatures() {
this.temperatureService.getRecentMachineTemperatures(this.machine_id)
.subscribe(
res => {
let device1 = res[0];
this.deviceId = device1.device_id;
this.initTemperatures(device1.temperatures);
this.updateChart();
},
error => console.log(error));
}
My Test sets up dependencies, spies on the service 'getRecentMachineTemperatures' and sets i to return some stub data. I've been googling around for ways to test this, thus resulting in 3 different test, trying to test the same thing. Each giving me a different error.
temperature.component.spec.ts:
let machine_id = 1;
let comp: TemperatureComponent;
let fixture: ComponentFixture<TemperatureComponent>;
let de: DebugElement;
let el: HTMLElement;
let temperatureService: TemperatureService;
let stubDevices: IDeviceReadings[];
let stubTemperatures: ITemperature[];
let spyRecentTemps: Function;
describe('Component: Temperature', () => {
beforeEach(() => {
TestBed.configureTestingModule({
declarations: [TemperatureComponent],
imports: [ ChartsModule ],
providers: [
MockBackend,
BaseRequestOptions,
{ provide: Http,
useFactory: (backend, defaultOptions) => {
return new Http(backend, defaultOptions);
},
deps: [MockBackend, BaseRequestOptions]},
TemperatureService
]
});
stubDevices = new Array<IDeviceReadings>();
let stubDevice = new IDeviceReadings();
stubDevice.device_id = 'stub device';
stubDevice.temperatures = new Array<ITemperature>();
let stubTemp = new ITemperature();
stubTemp.timestamp = new Date().getTime();
stubTemp.value = 10;
stubDevice.temperatures.push(stubTemp);
stubDevices.push(stubDevice);
stubTemperatures = new Array<ITemperature>();
let stubTemp2 = new ITemperature();
stubTemp.timestamp = new Date().getTime() + 1;
stubTemp.value = 11;
stubTemperatures.push(stubTemp2);
fixture = TestBed.createComponent(TemperatureComponent);
comp = fixture.componentInstance;
temperatureService = fixture.debugElement.injector.get(TemperatureService);
spyRecentTemps = spyOn(temperatureService, 'getRecentMachineTemperatures')
.and.returnValue(Observable.of(stubDevices).delay(1));
// get the "temperature-component" element by CSS selector (e.g., by class name)
de = fixture.debugElement.query(By.css('.temperature-component'));
el = de.nativeElement;
});
it('should show device readings after getRecentTemperatures subscribe (fakeAsync)', fakeAsync(() => {
fixture.detectChanges();
expect(spyRecentTemps.calls.any()).toBe(true, 'getRecentTemperatures called');
tick(1000);
fixture.detectChanges();
expect(el.textContent).toContain(stubDevices[0].temperatures[0].timestamp);
expect(el.textContent).toContain(stubDevices[0].temperatures[0].value);
}));
it('should show device readings after getRecentTemperatures subscribe (async)', async(() => {
fixture.detectChanges();
expect(spyRecentTemps.calls.any()).toBe(true, 'getRecentTemperatures called');
fixture.whenStable().then(() => {
fixture.detectChanges();
expect(el.textContent).toContain(stubDevices[0].temperatures[0].timestamp);
expect(el.textContent).toContain(stubDevices[0].temperatures[0].value);
});
}));
it('should show device readings after getRecentTemperatures subscribe (async) (done)', (done) => {
async(() => {
fixture.detectChanges();
expect(spyRecentTemps.calls.any()).toBe(true, 'getRecentTemperatures called');
fixture.whenStable().then(() => {
fixture.detectChanges();
expect(el.textContent).toContain(stubDevices[0].temperatures[0].timestamp);
expect(el.textContent).toContain(stubDevices[0].temperatures[0].value);
}).then(done);
});
});
});
fakeAsync fails with: 'Error: 1 timer(s) still in the queue.'
async fails with: 'Error: Cannot use setInterval from within an async zone test.'
async (done) fails with: 'Error: Timeout - Async callback was not invoked within timeout specified by jasmine.DEFAULT_TIMEOUT_INTERVAL.'
How would I go about testing components with a async service dependency?
From what I understand it might be something about the AsyncScheduler within the Rx library using Date().now instead of faked time (https://github.com/angular/angular/issues/10127). If so has this been fixed? Or anyone found a workaround?
I'm using angular-cli: 1.0.0-beta.16. node: 4.4.2. npm: 3.10.6. webpack 2.1.0-beta.22.

Answer 1

I had ..
import 'rxjs/add/operator/timeout';
return this.http[method](url, emit, this.options)
.timeout(Config.http.timeout, new Error('timeout'))
Which was causing this error. I believe under the hood RXJS .timeout is calling setInterval.
I fixed this by switching ...
it('blah', async(() => {
to
it('blah', (done) => {