Question

假设这样的服务：

@Injectable()
export class PageNavService {
    private _expanded = true;
    private pageNavExpanded = new Subject<any>();

    public togglePageNav(): void {
        this._expanded = !this._expanded
        this.pageNavExpanded.next(this._expanded);
    }

    public setPageNavState(expanded) {
        this._expanded = expanded;
        this.pageNavExpanded.next(this._expanded);
    }

    public getPageNavState(): Observable<any> {
        return this.pageNavExpanded.asObservable();
    }

    constructor() { }
}

如何测试togglePageNav()方法？

这是我的尝试：

describe('PageNavService', () => {
    let service;
    let state;

    beforeEach(() => TestBed.configureTestingModule({
        providers: [PageNavService]
    }));

    beforeEach(inject([PageNavService], svc => {
        service = svc;
        service.getPageNavState().subscribe((s) => {
            state = s;
        });
    }));

    describe('togglePageNav method', () => {
        it('should reverse the navbar state', () => {
            service.togglePageNav();
            expect(state).toBeTruthy();
        });
    });
});

然而，测试失败了：

预计虚假是真的。

Answer 1

您应该调用方法 $query = new WP_Query( array('post_type' => 'post', 'posts_per_page' =>2, 'order' => 'DESC', 'tax_query' => array( 'taxonomy' => 'NAME OF YOUR CATEGORY', 'field' => 'slug', 'terms' => 'category', ), ))); ，

getPageNavState()

Answer 2

因为你的初始状态是true，所以测试不能成功，让我解释一下。

describe('PageNavService', () => {
    let service;
    let state;

    beforeEach(() => TestBed.configureTestingModule({
        providers: [PageNavService]
    }));

    beforeEach(inject([PageNavService], svc => {
        service = svc;
        //At this moment, the state inside the service is true
        service.getPageNavState().subscribe((s) => {
            state = s;
        });
    }));

    describe('togglePageNav method', () => {
        it('should reverse the navbar state', () => {
            //Toggle will change the state from its initial state to an opposite one, making it false
            service.togglePageNav();
            //The test fails because the state is now false.
            expect(state).toBeTruthy();
        });
    });
});

您可以将初始状态（private _expanded）更改为false或将测试更改为false，因为这是您目前应该获得的。

如何测试操作局部变量并返回可观察的Angular服务方法？

2 个答案: