相关疑难解决方法(0)

在角度2中运行茉莉花规格时出现此错误：

无法读取null茉莉花角2的属性'injector'

堆栈跟踪：

TypeError: Cannot read property 'injector' of null
    at TestBed._createCompilerAndModule (http://localhost:3002/node_modules/@angular/core/bundles/core-testing.umd.js:834:48)
    at TestBed._initIfNeeded (http://localhost:3002/node_modules/@angular/core/bundles/core-testing.umd.js:800:43)
    at TestBed.createComponent (http://localhost:3002/node_modules/@angular/core/bundles/core-testing.umd.js:884:18)
    at Function.TestBed.createComponent (http://localhost:3002/node_modules/@angular/core/bundles/core-testing.umd.js:714:33)
    at Object.eval (http://localhost:3002/js/app/landing-page/subcomponents/middle-row.component.spec.js:29:49)
    at ZoneDelegate.invoke (http://localhost:3002/node_modules/zone.js/dist/zone.js:232:26)
    at ProxyZoneSpec.onInvoke (http://localhost:3002/node_modules/zone.js/dist/proxy.js:79:39)
    at ZoneDelegate.invoke (http://localhost:3002/node_modules/zone.js/dist/zone.js:231:32)
    at Zone.run (http://localhost:3002/node_modules/zone.js/dist/zone.js:114:43)
    at Object.eval (http://localhost:3002/node_modules/zone.js/dist/jasmine-patch.js:102:34)

我从官方的angular 2测试文档中复制了此规范：

let comp:    BannerComponent;
let fixture: ComponentFixture<BannerComponent>;
let de:      DebugElement;
let el:      HTMLElement;

describe('BannerComponent', () => {
  beforeEach(() => {
    TestBed.configureTestingModule({
      declarations: [ BannerComponent ], // declare the test component
    });

    fixture = TestBed.createComponent(BannerComponent);

    comp = fixture.componentInstance; …