未捕获的类型错误:无法在存储单元测试中将未定义或null转换为对象

Question

我无法解决此问题未捕获类型错误：当我运行单元测试时，无法将未定义或null转换为对象。我不知道为什么我会出现这个错误，因为数据出现在订阅中。有人能帮我修一下吗？

ts

locations$ = this.store.select((state: IAppState): Locations => state.locations.locations);
getLocations(): void {
this.store.dispatch(GetLocations({ reset: this.reset }));
console.log(this.locations$)
this.locations$(here is an error).subscribe((item) => {
if (item) {
const key = 'content';
this.locations = Array.from(Object.values(item[key]));
this.reset = false;
}
});
}

规范

const storeMock = jasmine.createSpyObj('store', ['select', 'dispatch']);
storeMock.select = () => of([fakeLocations] as any);
beforeEach(async(() => {
TestBed.configureTestingModule({
declarations: [
MyComponent, 
...
],
imports: [
...
],
providers: [
...
{ provide: Store, useValue: storeMock }
]
}).compileComponents();
}));
beforeEach(() => {
fixture = TestBed.createComponent(UbsAdminTariffsLocationDashboardComponent);
component = fixture.componentInstance;
fixture.detectChanges();
router = TestBed.inject(Router);
httpMock = TestBed.inject(HttpTestingController);
});
it('should create', () => {
expect(component).toBeTruthy();
});

谢谢你的帮助！

Answer 1

我认为这一行：

storeMock.select = () => of([fakeLocations] as any);

是导致问题的原因。

您正在从一个对象访问位置：

this.store.select((state: IAppState): Locations => state.locations.locations);

所以我认为你必须提供一个这样的对象。

试试这个：

// storeMock.select = () => of([fakeLocations] as any);
storeMock.select.and.returnValue(of({ locations: { locations: of[fakeLocations] } }));

我认为通过以上内容，我们将正确地嘲笑state.locations.locations。

编辑我认为这一行有问题：

if (item) {
const key = 'content';
// !! comment out below line and see if the error goes away
//    this.locations = Array.from(Object.values(item[key]));
this.reset = false;
}

如果错误在上面的行中消失，那么我认为item[key]是未定义的或null，Object.values抛出了这个错误。