Overriding a non-singleton service in an Angular component test ~ http://azanebrain.github.io/news/angular-snafoo-testing-component-with-overriden-providers

testing-angular-component-with-overriden-providers.ts

beforeEach(async(() => {
    TestBed.configureTestingModule({
      imports: [MyComponentModule],
      providers: [
        { provide: SomeSingletonService, useValue: new SomeSingletonServiceMock() }
      ]
    })
      .overrideComponent(MyCompComponent, {
        set: {
          providers: [
            { provide: NonSingletonService, useClass: NonSingletonServiceMock }
          ]
        }
      })
      .compileComponents()
  }))