@Input的默认值被测试包装中的`unfined`覆盖

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

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

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

  beforeEach(() => {
    fixture = TestBed.createComponent(YourComponent);
    component = fixture.componentInstance;
    // 设置输入值
    component.yourInputProperty = 'defaultValue'; // 或者使用fixture.detectChanges();
    fixture.detectChanges();
  });

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

@Component({
  selector: 'app-your-component',
  template: `<div>{{ yourInputProperty! }}</div>`
})
export class YourComponent {
  @Input() yourInputProperty: string = 'defaultValue';
}

@Component({
  selector: 'app-your-component',
  template: `<div>{{ yourInputProperty }}</div>`
})
export class YourComponent implements OnInit {
  @Input() yourInputProperty: string = 'defaultValue';

  ngOnInit() {
    // 确保这里的逻辑不会将yourInputProperty设置为undefined
  }
}

it('should use default value when input is undefined', () => {
  component.yourInputProperty = undefined;
  fixture.detectChanges();
  expect(component.yourInputProperty).toBe('defaultValue');
});