How override Provider in Angular 5 for only one test?

Question

In one of my unit test files, I have to mock several times the same service with different mocks.

import { MyService } from \'../services/myservice.service\'         


        

Answer 1

Just for reference, if annynone meets this issue.

I tried to use

TestBed.overrideProvider(MockedService, {useValue: { foo: () => {} } });

it was not working, still the original service was injected in test (that with providedIn: root)

In test I used alias to import OtherService:

import { OtherService } from '@core/OtherService'`

while in the service itself I had import with relative path:

import { OtherService } from '../../../OtherService'

After correcting it so both test and service itself had same imports TestBed.overrideProvider() started to take effect.

Env: Angular 7 library - not application and jest