Mock storage

When you need to interact with storage but still you are testing only a unit of the code, you can use MockStorage class for this purpose. Mocked version doesn't take into account stuff like size limits and other things taken care by window.localstorage API and just focuses on core functionality.

1. Usage

let storage: Storage;

beforeEach(async () => {
    await TestBed.configureTestingModule({
        providers: [
            {
                provide: LOCAL_STORAGE,
                useClass: MockStorage,
            },
            {
                provide: SESSION_STORAGE,
                useClass: MockStorage,
            },
        ],
    });
    storage = TestBed.inject(Storage);
});