Angular Router - Jest unit Test

I am new to the Angular unit test.

We have used the jest testing framework in Angular.

I have basic knowledge in jest and can work with the basic testing. But in Angular routing I feel is complex

import { Component } from '@angular/core';
import { Router, RouteConfigLoadStart, RouteConfigLoadEnd, RouterEvent, NavigationStart, NavigationEnd, Event, NavigationCancel, 
  NavigationError } from '@angular/router';
import { NgxSpinnerService } from 'ngx-spinner';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  title = 'Angular';
  loading: boolean = false;
  constructor(router: Router, private spinner: NgxSpinnerService) {
    router.events.subscribe(
      (event: RouterEvent): void => {
        if (event instanceof RouteConfigLoadStart) {
          this.loading = true;
        } else if (event instanceof RouteConfigLoadEnd) {
          this.loading = false;
        }

      }
    );
  }
}

Can anyone help me with how to test the above code?