如何为打开模式的 Angular Http 拦截器编写单元测试?

How can I write a unit test for an Angular5 HttpInterceptor that opens a modal?

我的拦截器是:

@Injectable()
export class ErrorInterceptor implements HttpInterceptor {
  constructor(private _ngbModal: NgbModal) {}

  intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    return next.handle(request)
    .catch((err) => {
      let componentInstance = this._ngbModal.open(ErrormodalComponent, {size: 'sm', backdrop: 'static' }).componentInstance

      switch(err.status) {
        case 401:
          componentInstance["message"] = "User session lost, please logout and log back in."
          break;
        case 404:
          componentInstance["message"] = "API Route Not found"
          break;
        default:
          componentInstance["message"] = "API Currently Unavailable. Please try again."
          break;


      }
      return Observable.throw(err);
    })
  }
}

而且我想编写一个测试来检查是否打开了模式,并根据状态显示了适当的消息。

谢谢

我会嘲笑 _ngbModal 并监视 open 方法并返回一个组件实例并检查 componentInstance 上的消息键。

由于_ngbModal是第三方的并且已经过测试,所以没必要实际测试模态

希望对您有所帮助。