首页 > 解决方案 > 为什么我得到“ReducerManager 没有提供者!” 使用ngrx对延迟加载的Angular 6应用程序进行单元测试时出错?

问题描述

我有一个使用ngrx的延迟加载Angular 6 应用程序。我有一个:

app.module.ts
shared.module.ts
core.module.ts

核心模块有页脚和页眉之类的东西。这里没有与 store/ngrx 相关的东西,但是标头的单元测试(在实现 ngrx 之前工作)一直失败,并出现以下错误:

StaticInjectorError(Platform: core)[StoreFeatureModule -> ReducerManager]: NullInjectorError: No provider for ReducerManager!

我能想到的唯一一件事StoreModule是 没有导入CoreModule. 但应该吗?当标头与状态无关时,为什么测试会失败?

app.module.ts

@NgModule({
declarations: [
    AppComponent,
    LoginComponent,
],
imports: [
    BrowserModule,
    AppRoutingModule,
    CoreModule,
    SharedModule.forRoot(),
    StoreModule.forRoot({}),
    EffectsModule.forRoot([]),
    !environment.production ? StoreDevtoolsModule.instrument({
        maxAge: 5   // retains last 5 states
    }) : []
],
providers: [],
bootstrap: [ AppComponent ]

})

核心模块.ts

@NgModule({
    imports: [
        CommonModule,
    ],
    exports: [
        CommonModule,
        HeaderComponent,
        FooterComponent
    ],
    declarations: [
        HeaderComponent, 
        FooterComponent, 
    ]
})

shared.module.ts

@NgModule({
    imports: [
        CommonModule,
        HttpClientModule
    ],
    exports: [
        CommonModule,
        MyComponent
    ],
    declarations: [ MyComponent]
})
export class SharedModule {

** header.component.spec.ts**

describe('HeaderComponent', () => {
    let component: HeaderComponent;
    let fixture: ComponentFixture<HeaderComponent>;
    let debugEl: DebugElement;

    beforeEach(async(() => {
        TestBed.configureTestingModule({
            imports: [ 
                ProductsModule,
                CustomersModule
        ],
        declarations: [ HeaderComponent ],
        providers: [
            { provide: myService, useValue: new MyService() },
        ],
    })
    .compileComponents();
}));

beforeEach(() => {
    fixture = TestBed.createComponent(HeaderComponent);
    component = fixture.componentInstance;
    debugEl = fixture.debugElement;
    fixture.detectChanges();
});

标签: javascriptangularlazy-loadingangular6ngrx

解决方案


因为您的组件使用 NgRx 存储,所以您还必须在TestBed.


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