Question

我正在尝试测试组件中的主题更改，但覆盖范围从未进入订阅功能。

标题栏-search.component.ts

export class TitlebarSearch implements OnInit {

    @ViewChild('titleSearchInput') titleSearchInputEl: any;
    @Input() inputValue: string;
    @Output() searchText = new EventEmitter<string>();
    searchChange: Subject<string> = new Subject<string>();


    constructor(private renderer: Renderer) {

    }    

    /**
     * Waits a time before send the text to search
     * 
     * @protected
     * @memberof TitlebarSearch    
     * 
     */
    protected prepareSearchInput() {
        this.searchChange.debounceTime(500).subscribe(value => {
            this.searchText.emit(value);
        });
    }

    /**
     * Send the text to the searchChange Observable
     * 
     * @param {string} text 
     * @memberof TitlebarSearch
     */
    public doSubmit(text:string){
        this.searchChange.next(text);        
    }    

}

标题栏-search.component.spec.ts

describe('Titlebar Search tests', () => {
    let fixture;
    let titlebarComponent;

    beforeEach(async(() => {
        //Creates a UserService using a mock class
        TestBed.configureTestingModule({
            declarations: [TitlebarSearch],
            imports: [FormsModule],
            //CUSTOM_ELEMENTS_SCHEMA to solve html elements issues
            schemas: [ CUSTOM_ELEMENTS_SCHEMA ],
            providers: [Renderer]
        }).compileComponents().then(() => {
            fixture = TestBed.createComponent(TitlebarSearch);            
            titlebarComponent = fixture.componentInstance
        });

    }));

    //specs
    it('should send the text to detect the change', async((done) => {        
        const text = "Changed text";
        titlebarComponent.doSubmit(text);
        fixture.detectChanges();
        titlebarComponent.searchChange.subscribe(textRecived => {
            expect(textRecived).toEqual(text);
            done();
        })     
    }));           
});

当输入文本被更改时，将调用doSubmit方法。然后，prepareSearchInput订阅主题以获得下一个debounce并输出相同的文本。

我不知道测试中的错误在哪里，但覆盖范围从未涵盖订阅代码。互联网上的例子对我没有帮助。

Answer 1

我遇到了同样的问题，但在这个帖子中得到了@jonrsharpe的答案：Unit test Angular 2 service subject。

在调用next()之前，您需要在测试中更早地声明主题订阅。如果你像这样重新排序，它应该工作：

it('should send the text to detect the change', async((done) => {        
    titlebarComponent.searchChange.subscribe(textRecived => {
        expect(textRecived).toEqual(text);
        done();
    })   
    const text = "Changed text";
    titlebarComponent.doSubmit(text);
    fixture.detectChanges();
}));

约翰说，问题是你的主题没有任何重播/缓冲行为。

角度单位测试观察/主题与业力

1 个答案: