Question

我想测试NGXS中的操作，但由于需要模拟的服务而失败。谷歌搜索发现有多种方法来模拟服务。

测试

describe('UserState', () => {
    let store: Store;

    beforeEach(() => {
        TestBed.configureTestingModule({
            imports: [
                NgxsModule.forRoot([UserState]),
                HttpClientModule,
                AngularFireModule.initializeApp(environment.firebase),
                AngularFirestoreModule,
                AngularFireAuthModule
            ],
            providers: [{provide: DatabaseService, useValue: {updateUserField: of(1)}}]
        });

        store = TestBed.get(Store);
    });

    it('should update user settings', () => {
        store.dispatch(new UpdateUserSettingsAction({alias: 'Naruto'} as Settings));
        const userModel: UserModel = store.selectSnapshot(state => state.user);
        expect(userModel.settings).toBeDefined();
    });
});

操作

  @Action(UpdateUserSettingsAction)
    updateUserSettings(ctx: StateContext<UserModel>, action: UpdateUserSettingsAction) {
        const user = ctx.getState();
        return this.databaseService.updateUserField('settings', action.settings)
            .pipe(
                first(),
                tap(() => {
                    ctx.setState({
                        ...user,
                        settings: action.settings
                    });
                })
            );
    }

错误

this.databaseService.updateUserField is not a function

您看到我的错误了吗？

Answer 1

问题在于updateUserField是您的真实服务中的一个函数，但在您的模拟中它只是一个属性。以下更改应使其起作用：

providers: [{provide: DatabaseService, useValue: {updateUserField: () => of(1) }}]

我所做的只是添加了() =>，这样它就变成了返回您的of(1)的函数

角度TestBed模拟服务

1 个答案: