Question

在测试组件时，出现TypeError: Cannot read property 'dispatchEvent' of null错误。这是我的代码：

describe('SubSystemComponent', () => {

    let component: SubSystemComponent;
    let fixture: ComponentFixture<SubSystemComponent>;
    let store: Store<ModelPFServices>;


    beforeEach(async(() => {
        TestBed.configureTestingModule({
            declarations: [SubSystemComponent],
            schemas: [CUSTOM_ELEMENTS_SCHEMA],
            imports: [
                HttpClientTestingModule,
                FormsModule,
                ReactiveFormsModule,
                StoreModule.forRoot({}, { runtimeChecks: { strictStateImmutability: true, strictActionImmutability: true } }),
                StoreModule.forFeature('pfservice', reducer),
                EffectsModule.forRoot([]),
                EffectsModule.forFeature([EffectsSubSystem])
            ]
        })
        .compileComponents();

        store = TestBed.get(Store);
        spyOn(store, 'dispatch').and.callThrough();


    }));

    beforeEach(() => {
        fixture = TestBed.createComponent(SubSystemComponent);
        component = fixture.componentInstance;
        spyOn(component.ssRemoved, 'emit');
        fixture.detectChanges();
    });

    it('should create', () => {
        expect(component).toBeTruthy();
    });

    it('should delete a id', () => {
//this part shows error
        const nativeElement = fixture.nativeElement;
        const button = nativeElement.querySelector('.delete-item');
        button.dispatchEvent(new MouseEvent('click'));
        fixture.detectChanges();

    });

});

我的代码有什么问题或如何解决？有人帮我吗？

Answer 1

您需要在imports语句中的configureTestingModule中传递存储服务，因为现在您得到的是空服务。函数TestBed.get（store）返回null

`TypeError：无法读取null的属性'dispatchEvent'-用开玩笑进行角度测试

1 个答案: