如何使用Jasmine测试Angular 6的ng容器中封装的元素？

import { TestBed, ComponentFixture } from '@angular/core/testing';
import { MyComponent } from './my.component';

describe('MyComponent', () => {
  let component: MyComponent;
  let fixture: ComponentFixture<MyComponent>;

  beforeEach(async () => {
    await TestBed.configureTestingModule({
      declarations: [ MyComponent ]
    })
    .compileComponents();
  });

  beforeEach(() => {
    fixture = TestBed.createComponent(MyComponent);
    component = fixture.componentInstance;
    fixture.detectChanges();
  });

  it('should create', () => {
    expect(component).toBeTruthy();
  });

  it('should have a title', () => {
    expect(component.title).toBeDefined();
  });

  it('should render the title in the template', () => {
    const compiled = fixture.nativeElement;
    expect(compiled.querySelector('h1').textContent).toContain(component.title);
  });
});