测试台：为什么注入默认类而不是我的间谍

Question

我有这个设置代码用于我的测试

beforeEach(() => {
        loggerServiceSpy = jasmine.createSpyObj('LoggerService', ['log', 'naam']);
        TestBed.configureTestingModule({
            declarations: [UserslistComponent, BizPipe],
            providers: [
                { provide: UserdataService, useClass: MockUserdataService },
                { provide: LoggerService, useValue: loggerServiceSpy }
            ]
        }).compileComponents();
        fixture = TestBed.createComponent(UserslistComponent); 
        component = fixture.componentInstance;
        fixture.detectChanges();
    });

我想要它做的是注入MockUserdataService 的实例（确实如此）和创建的loggerServiceSpy。

现在在UserslistComponent 中，LoggerService 的注入类型是“真实的”LoggerService，而不是我的间谍。

我已经通过控制台记录 LoggerService 的名称看到了这一点（我给 loggerservice 一个 name 属性）。

这是UserslistComponent 的构造函数： constructor(private userDataService: UserdataService, private logger: LoggerService) {

Answer 1

如果组件中提供了服务，则尝试覆盖组件：

beforeEach(() => {
        loggerServiceSpy = jasmine.createSpyObj('LoggerService', ['log', 'naam']);
        TestBed.configureTestingModule({
            declarations: [UserslistComponent, BizPipe],

        }).overrideComponent(UserslistComponent, {
            set: {
                providers: [
                { provide: UserdataService, useClass: MockUserdataService },
                { provide: LoggerService, useValue: loggerServiceSpy }
            ],
            }
        }).compileComponents();
        fixture = TestBed.createComponent(UserslistComponent); 
        component = fixture.componentInstance;
        fixture.detectChanges();
    });