How can I mock an Observable.throw in an Angular2 test?

Question

I want to test the error handling in my Angular2 component and therefore want to mock a service to return an Observable.throw(\'error\'). How can that be done using Jasmine and

Answer 1

You can simply mock Observable and throw error object using Observable.throw({status: 404}) and test error block of observable.

const xService = fixture.debugElement.injector.get(SomeService);
const mockCall = spyOn(xService, 'xMethod')
                       .and.returnValue(Observable.throw({status: 404}));

Here I am throwing http 404 error from Observable.throw({status: 404}) by mocking xMethod of xSerive in my test.