Mock static data in a service - angular 2 testing

Question

In my ANGULAR 2 application there is a service; that contains a static reference property.

export class MyService {
    public static OneProperty: ClassA;
}

And here is a sample implementation of the method I am going to test in my ts file.

export class TestComponent() {
    oneProperty: User;

    public NumberOfUsers(): string {
    this.oneProperty = MyService.OneProperty.someThing;
    return this.oneProperty;
    }
}

How can I mock the data in the static variable for the test cases? Whenever I try to mock the data in useClass/useValue format, I am getting a undefined value for MyService.OneProperty.

Answer 1

Can you please post an example of how did you try useClass/useValue?

This should work:

class MockMyService {
  public static oneProperty = 'mock';
}

Then in your tests:

describe('TestComponent', () => {
  beforeEach(() => TestBed.configureTestingModule({
    ...
    providers: [
      {provide: MyService, useClass: MockMyService},
    ]
  });

  it('should work with mock service', () => {
    const mockService = TestBed.get(MyService);
    expect(mockService.oneProperty).toEqual('mock');
  });
});

The above is just pseudo-like, I couldn't test it anywhere, but this should give you an idea.