How to fix undefined is not an object (evaluating 'newOptions.merge')? - unit-testing

Question

I am writing angular 2 app. This test is created by angular cli and fails by default:
it('should render title in a h1 tag', async(() => {
let fixture = TestBed.createComponent(AppComponent);
fixture.detectChanges();
let compiled = fixture.debugElement.nativeElement;
expect(compiled.querySelector('h1').textContent).toContain('app works!');
}));
Error message is:
Failed: Error in ./AppComponent class AppComponent - inline template:51:14 caused by: undefined is not an object (evaluating 'newOptions.merge')
mergeOptions#webpack:///~/#angular/http/src/http.js:47:0 <- src/test.ts:69434:22
get#webpack:///~/#angular/http/src/http.js:147:0 <- src/test.ts:69534:110
As I can found newOptions.merge is called from mergeOptions method inside node_modules/#angular/http/src/http.js.
What I have to do in order to make tests passing?
Here is gist fro app.component.ts
Her is gist for app.component.html

Answer 1

You are using Angular 2 Http service, so you need to inject defaultOptions parameter, which is, in your case, empty.
Best scenario to make this work is to add the following lines in your spec.ts file:
beforeEach(() => {
TestBed.configureTestingModule({
providers: [{
provide: Http,
useFactory: (
backend: ConnectionBackend,
defaultOptions: BaseRequestOptions
) => {
return new Http(backend, defaultOptions);
},
deps: [BaseRequestOptions]
},
{
provide: BaseRequestOptions,
useClass: BaseRequestOptions
}
]
});
});
So, the line when you tell that provider BaseRequestOption uses class BaseRequestOptions is crucial.