unit-testing - 使用 Jasmine、mouseenter/mouseleave-test 进行 Angular2 测试

Question

我有一个 HighlightDirective，它会在鼠标进入某个区域时突出显示，例如:

@Directive({
  selector: '[myHighlight]',
  host: {
    '(mouseenter)': 'onMouseEnter()',
    '(mouseleave)': 'onMouseLeave()'
  }
})
export class HighlightDirective {
  private _defaultColor = 'Gainsboro';
  private el: HTMLElement;

  constructor(el: ElementRef) { this.el = el.nativeElement; }

  @Input('myHighlight') highlightColor: string;

  onMouseEnter() { this.highlight(this.highlightColor || this._defaultColor); }
  onMouseLeave() { this.highlight(null); }

  private highlight(color:string) {
    this.el.style.backgroundColor = color;
  }

}

现在我想测试(正确的)方法是否在事件上被调用。所以像这样:

  it('Check if item will be highlighted', inject( [TestComponentBuilder], (_tcb: TestComponentBuilder) => {
    return _tcb
      .createAsync(TestHighlight)
      .then( (fixture) => {
        fixture.detectChanges();
        let element = fixture.nativeElement;
        let component = fixture.componentInstance;
        spyOn(component, 'onMouseEnter');
        let div = element.querySelector('div');


        div.mouseenter();


        expect(component.onMouseEnter).toHaveBeenCalled();
      });
  }));

与测试类:

@Component({
  template: `<div myHighlight (mouseenter)='onMouseEnter()' (mouseleave)='onMouseLeave()'></div>`,
  directives: [HighlightDirective]
})
class TestHighlight {
  onMouseEnter() {
  }
  onMouseLeave() {
  }
}

现在，我收到消息:

Failed: div.mouseenter is not a function

那么，有人知道哪个是正确的功能(如果存在的话)吗？我已经尝试过使用 click()..

谢谢!

Answer 1

代替

div.mouseenter();

这应该有效:

let event = new Event('mouseenter');
div.dispatchEvent(event);