Angular 2测试设置

Question

我尝试使用以下设置测试Angular 2组件：

import { TestBed } from '@angular/core/testing';
import { By }     from '@angular/platform-browser';

import { GroceriesListComponent } from './groceries-list.component';
import { GroceryService }        from './grocery.service';

let comp: GroceriesListComponent;
let fixture: ComponentFixture<GroceriesListComponent>;

beforeEach(() => {
  TestBed.configureTestingModule({
    declarations: [GroceriesListComponent],
    providers:    [GroceryService]
  });

  fixture = TestBed.createComponent(GroceriesListComponent);
  comp = fixture.componentInstance;

  _groceryService = fixture.debugElement.injector.get(GroceryService);

  spy = spyOn(_groceryService, 'getGroceries')
    .and.returnValue(Promise.resolve(testGroceries));

  de = fixture.debugElement.query(By.css('li'));
  el = de.nativeElement;
});

...但我在我的控制台中一直收到以下错误，并且由于缺少信息性错误消息，我对我的设置有什么问题感到遗憾：

404: /base/traceur
ERROR
{
  "originalErr": {}
}

Answer 1

这真是一个令人烦恼的错误，我花了一些时间才意识到＆＃34; traceur＆＃34;是SystemJS transpiler的默认值。

解决方案是如下调整这两个文件（karma.conf.js和karma-test-shim.js），以便打字稿获取你的转换器：

karma.conf.js

＆＃13;

＆＃13;

a = b

＆＃13;

＆＃13;

＆＃13;

果报测试shim.js

＆＃13;

＆＃13;

const char* const a = "test";

＆＃13;

＆＃13;

＆＃13;