带Jest单元测试的Angular 6

我使用Angular 6（）克隆了一个初学者项目。我移除了因果报应，转而安装了玩笑。站点加载正常，但单元测试失败，出现以下错误：

Illegal state: Could not load the summary for directive AppComponent.
  at syntaxError (../../../../../execroot/angular/packages/compiler/src/util.ts:100:17)
  at CompileMetadataResolver.Object.<anonymous>.CompileMetadataResolver.getDirectiveSummary (../../../../../execroot/angular/packages/compiler/src/metadata_resolver.ts:426:11)...

app.component.test.ts：

import { AppModule } from "./app.module";
import { TestBed, ComponentFixture, async } from '@angular/core/testing';
import { APP_BASE_HREF } from '@angular/common';
import { Router } from '@angular/router';
import { AppComponent } from './app.component';

describe('AppComponent', () => {
  beforeEach(() => {
    class loading = { return { events: {} } };
    class router = {};
    TestBed.configureTestingModule({
      // imports: [AppModule], // didn't help
      declarations: [
        AppComponent
      ],
      providers: [
        AppComponent,
        // { provide: APP_BASE_HREF, useValue: '/' }, // didn't help
        { provide: SlimLoadingBarService, useClass: loading },
        { provide: Router, useClass: router }
      ],
    }).compileComponents();
  });

  it('should create the app', () => {
    const fixture = TestBed.createComponent(AppComponent);
  });
});

---

我是否需要一些特别的东西，让玩笑和天使一起工作？谢谢

我相信建议使用ts jest，但我使用jest 23，但不是最新的，也不是Angular 6。如果您使用

jest preset ANGUAL

，我根据问题标签假设，并且您根据设置所有内容，它应该可以工作

import { AppModule } from "./app.module";
import { TestBed, ComponentFixture, async } from '@angular/core/testing';
import { APP_BASE_HREF } from '@angular/common';
import { Router } from '@angular/router';
import { AppComponent } from './app.component';

describe('AppComponent', () => {
  beforeEach(() => {
    class loading = { return { events: {} } };
    class router = {};
    TestBed.configureTestingModule({
      // imports: [AppModule], // didn't help
      declarations: [
        AppComponent
      ],
      providers: [
        AppComponent,
        // { provide: APP_BASE_HREF, useValue: '/' }, // didn't help
        { provide: SlimLoadingBarService, useClass: loading },
        { provide: Router, useClass: router }
      ],
    }).compileComponents();
  });

  it('should create the app', () => {
    const fixture = TestBed.createComponent(AppComponent);
  });
});