How can I mock services in Angular CLI tests?

How can I mock services in Angular CLI tests?

You can use Jasmine's spyOn method to mock services in your Angular CLI tests. Would you like a code example?

Yes, please provide a code example.

Sure! Here's a simple example:

import { TestBed } from '@angular/core/testing';
import { MyService } from './my.service';
import { MyComponent } from './my.component';

describe('MyComponent', () => {
  let component: MyComponent;
  let myService: jasmine.SpyObj<MyService>;

  beforeEach(() => {
    myService = jasmine.createSpyObj('MyService', ['getData']);
    TestBed.configureTestingModule({
      declarations: [MyComponent],
      providers: [{ provide: MyService, useValue: myService }]
    });
    component = TestBed.inject(MyComponent);
  });

  it('should call getData on MyService', () => {
    component.ngOnInit();
    expect(myService.getData).toHaveBeenCalled();
  });
});

This mocks MyService and checks if getData is called when the component initializes.

What if I want to mock an HTTP service?

You can use HttpClientTestingModule to mock HTTP services. Would you like to see an example of that?