如何使用Angular6在Jasmine中对NGRX功能选择器进行单元测试?

我有一个功能选择器和相邻的选择器 产品 特点:

const getProductState = createFeatureSelector<fromProducts.State>('products');

export const getOldProducts = createSelector(
    getProductState,
    state => state.oldProducts
);

export getNewProducts = createSelector(
    getProductState,
    state => state.newProducts
);

我想对这些选择器进行单元测试。我读的大多数文章和文章只处理非特征选择器,所以来模拟特性状态,我的测试返回。 undefined 对于state对象。我的规范文件如下所示:

beforeEach(async(() => {
    TestBed.configureTestingModule({
        imports: [
            StoreModule.forRoot({}),
            StoreModule.forFeature('products', fromProduct.reducer)
        ],
        declarations: [],
        providers: [{
            provide: Store, useClass: class { select = jasmine.createSpy('select'); dispatch = jasmine.createSpy('dispatch'); }
        }]
    })
    mockStore = TestBed.get(Store);
}));

it('getOldProducts should return the oldProducts', () => {
    const state = {
        name: 'Product1',
        oldProduct: {
            price: 45.00
        },
        newProduct: {
            price: 50.00
        }
    }: fromProduct.State;
    expect(selectors.getOldProducts(state.oldProducts)).toBe(state.oldProducts);
});

错误总是说 Cannot read property 'oldProducts' of undefined ,这让我相信 getProductState 功能选择器未正确模拟。

谢谢!