使用Router依赖对Angular服务进行单元测试："TypeError: Cannot read property 'navigate‘of undefined“

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

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

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

    // 创建一个模拟的路由器
    routerMock = {
      navigate: jasmine.createSpy('navigate')
    };

    // 使用模拟的路由器替换实际的路由器
    TestBed.overrideProvider(Router, { useValue: routerMock });
  });

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

  it('should call router navigate on button click', () => {
    const button = fixture.nativeElement.querySelector('button');
    button.click();

    expect(routerMock.navigate).toHaveBeenCalledWith(['/some-path']);
  });
});