Componentes con RouterLink

podemos ver como realizar este tipo de pruebas desde la página oficial de Angular en angular-testing , para poder realizar esto primero debemos crear un archivo que tenga la forma de hacer mock a las routes en la carpeta testing

router-link-directive-stub.ts

import { Directive, HostListener, Input } from '@angular/core';

@Directive({
  selector: '[routerLink]'
})

export class RouterLinkDirectiveStub {
  @Input('routerLink') linkParams: any;
  navigatedTo: any = null;

  @HostListener('click')
  onClick() {
    this.navigatedTo = this.linkParams;
  }
}

ahora podemos realizar pruebas desde el app.component.ts ya que ahi tenemos la mayor cantidad de routerlink activo

app.component.spec.ts

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

import { RouterLinkDirectiveStub } from './../testing/router-link-directive-stub';
import { queryAllByDirective } from 'src/testing';
  
describe('AppComponent', () => {
  let fixture: ComponentFixture<AppComponent>;
  let component: AppComponent;

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

  beforeEach(() => {
    fixture = TestBed.createComponent(AppComponent);
    component = fixture.componentInstance;
    fixture.detectChanges();
  });
  
 it('should there are 7 routerlinks', () => {
    const links = queryAllByDirective(fixture, RouterLinkDirectiveStub);
    expect(links.length).toEqual(7);
  });

  it('should there are 7 routerlinks with match routes', () => {
    const links = queryAllByDirective(fixture, RouterLinkDirectiveStub);
    const routerLinks = links.map(link => link.injector.get(RouterLinkDirectiveStub));
    expect(links.length).toEqual(7);
    expect(routerLinks[0].linkParams).toEqual('/');
    expect(routerLinks[1].linkParams).toEqual('/auth/register');
    expect(routerLinks[2].linkParams).toEqual('/people');
  });
});