how to do page navigation (routing) using karma-Jasmine test - karma-jasmine

Question

I am writing the angular (Karma-Jasmine) test cases and I want to navigate between the pages. How to navigate between pages using karma-Jasmine.

Answer 1

1) Test a component in which navigation is used: navigate method should be called when you do an action (assertion like toHaveBeenCalled OR toHaveBeenCalledWith)
it('should redirect the user to the users page after saving', () => {
let router = TestBed.get(Router);
let spy = spyOn(router, 'navigate');
component.save();
expect(spy).toHaveBeenCalledWith(['users'])
});
2) Also test your routes that proper component will be used
app.routes.spec.ts
import { routes } from './app.routes'
it('should contain a route for users', () => {
expect(routes).toContain({path: 'users', component: UserComponent})
});
3) You can use useValue for testing different activatedRouteParams (just configure then and pass to providers, see example).
Component ts file example:
ngOnInit() {
this.contextType = this.route.snapshot.paramMap.get('contextType');
this.contextId = this.route.snapshot.paramMap.get('contextId');
this.contextFriendlyId = this.route.snapshot.paramMap.get('contextFriendlyId');
}
Spec file (configureTestData is a function that allows you to pass different configurable values, in my case activatedRouteParams)
export function configureTestData(activatedRouteParams) {
beforeEach(async(() => {
TestBed.configureTestingModule({
declarations: [SetUpComponent],
imports: [RouterTestingModule],
providers: [
{
provide: ActivatedRoute, useValue: activatedRouteParams
}
]
});
}));
}
describe('SetUp Component:Folder ', () => {
let component: SetUpComponent;
let fixture: ComponentFixture<SetUpComponent>;
configureTestData({
snapshot: {
paramMap: convertToParamMap({
contextType: 'Folder',
contextId: 'FX6C3F2EDE-DB25-BC3D-0F16-D984753C9D2E',
contextFriendlyId: 'FX17373'
})
}
});
beforeEach(() => {
fixture = TestBed.createComponent(SetUpComponent);
component = fixture.componentInstance;
fixture.detectChanges();
});
it('should create set up component for folder', () => {
expect(component).toBeTruthy();
});
it('should create alert with required properties', () => {
expect(component.contextType).toEqual('Folder);
.... etc
});
});
4) router-outlet and routerLink
Template file:
<nav>
<a routerLink="todos"></a>
</nav>
<router-outlet></router-outlet>
beforeEach(() => {
TestBed.configureTestingModule({
imports: [RouterTestingModule.withRoutes([])],
declarations: [AppComponent]
});
});
it('should have router outlet', () => {
let de = fixture.debugElement.query(By.directive(RouterOutlet));
expect(de).not.toBeNull();
});
it('should have a link to todos page', () => {
let debugElements = fixture.debugElement.queryAll(By.directive(RouterLinkWithHref));
let index = debugElements.findIndex(de => de.properties['href'] === '/todos');
expect(index).toBeGreaterThan(-1);
});
5) Stub for ActivatedRoute where we can push params
component.ts
ngOnInit() {
this.route.params.subscribe(p => {
if (p['id'] === 0) {
this.router.navigate(['not-found']);
}
});
}
Spec file:
class RouterStub {
navigate(params) {}
}
class ActivatedRouteStub {
private subject = new Subject();
get params () {
return this.subject.asObservable();
}
push(value) {
this.subject.next(value);
}
}
describe('Navigation Testing', () => {
beforeEach(() => {
TestBed.configureTestingModule({
imports: [],
providers: [
{provide: Router, useClass: RouterStub},
{provide: ActivatedRoute, useClass: ActivatedRouteStub}
]
});
});
it('should navigate to invalid page when invalid params passed', () => {
let router = TestBed.get(Router);
let spy = spyOn(router, 'navigate');
let route: ActivatedRouteStub = TestBed.get(ActivatedRoute);
route.push({id: 0});
expect(spy).toHaveBeenCalledWith(['not-found'])
});
});