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How to perform checks after expect().toBeObservable() ?

See original GitHub issue

Back when I was using karma with jasmine-marbles I could write tests like this:

expect(result).toBeObservable(expected);
expect(mockInsideObservable).toHaveBeenCalled();

Which is easy to read and write. The main thing here is that expect.toBeObservable acts synchronously and waits for all the code inside the observable to be executed.

The same code in jest and jest-marbles will always fail with the following message:

Expected mock function to have been called, but it was not called

Because the last assertion is evaluated before the observable. Is this expected behavior? If so, would it be possible to provide some sort of promise or callback to the observable assertion?

Issue Analytics

State:
Created 4 years ago
Comments:8 (6 by maintainers)

Top GitHub Comments

3reactions

just-jebcommented, Sep 7, 2019

Please use toSatisfyOnFlush, available since 2.5.0.
Let me know if that helps.

1reaction

just-jebcommented, Jul 27, 2019

Currently it works in a way that the scheduler is being flashed after each test, therefore your observable is essentially invoked in afterEach.
I agree it should change and work in the same way jasmine-marbles work.
Until it is implemented please use the workaround provided above.

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