如何在Angular2中为具有数据绑定和管道的元素编写Jasmine单元测试

import { TestBed, ComponentFixture } from '@angular/core/testing';
import { AppComponent } from './app.component';
import { MyPipe } from './my.pipe';

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

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

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

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

  it('should display the correct value with data binding', () => {
    component.value = 'Test';
    fixture.detectChanges();
    const element = fixture.nativeElement.querySelector('.value');
    expect(element.textContent).toContain('Test');
  });

  it('should transform the value with pipe', () => {
    component.value = 'Test';
    fixture.detectChanges();
    const transformedValue = component.transformValue();
    expect(transformedValue).toBe('TEST');
  });
});