Angular 2/4/6/7 - Unit Testing with Router

Question

In Angular 2.0.0, I am unit testing a component that uses Router. However I get the \'Supplied parameters do not match any signature of call target.\' error. In Visual studi

Answer 1

Here an axample if we inject Route service in our component controller:

import { TestBed, async } from '@angular/core/testing';
import { RouterTestingModule } from '@angular/router/testing'; // Because we inject service in our component
import { Router } from '@angular/router'; // Just if we need to test Route Service functionality

import { AppComponent } from './app.component';
import { DummyLoginLayoutComponent } from '../../../testing/mock.components.spec'; // Because we inject service in your component

describe('AppComponent', () => {
  let router: Router; // Just if we need to test Route Service functionality

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [
        AppComponent,
        DummyLoginLayoutComponent // Because we inject service in our component
      ],
      imports: [
        RouterTestingModule.withRoutes([
          { path: 'login', component: DummyLoginLayoutComponent },
        ]) // Because we inject service in our component
      ],
    }).compileComponents();

    router = TestBed.get(Router); // Just if we need to test Route Service functionality
    router.initialNavigation(); // Just if we need to test Route Service functionality
  }));

  it('should create the app', async(() => {
    const fixture = TestBed.createComponent(AppComponent);
    const app = fixture.debugElement.componentInstance;
    expect(app).toBeTruthy();
  }));
});

We can also test other functionalitites such as navigate(). Just in case:

it('should call eventPage once with /register path if event is instanceof NavigationStart', fakeAsync(() => {
    spyOn(analyticService, 'eventPage');
    router.navigate(['register'])
      .then(() => {
        const baseUrl = window.location.origin;
        const url = `${baseUrl}/register`;
        expect(analyticService.eventPage).toHaveBeenCalledTimes(1);
        expect(analyticService.eventPage).toHaveBeenCalledWith(url);
      });
}));

My file with all mock components (mock.components.specs.ts)

import { Component } from '@angular/core';

@Component({
    selector: 'home',
    template: '
Dummy home component
',
    styleUrls: []
})

export class DummyHomeComponent { }