"Error: No provider for router" while writing Karma-Jasmine unit test cases

You need to import RouterTestingModule when setting up the test module.

  /* tslint:disable:no-unused-variable */  import { async, ComponentFixture, TestBed } from '@angular/core/testing';  import { By } from '@angular/platform-browser';  import { DebugElement } from '@angular/core';  import { RouterTestingModule } from '@angular/router/testing';  import { MyNewComponentComponent } from './my-new-component.component';  describe('MyNewComponentComponent', () => {    let component: MyNewComponentComponent;    let fixture: ComponentFixture<MyNewComponentComponent>;    beforeEach(async(() => {      TestBed.configureTestingModule({        imports: [RouterTestingModule],        declarations: [ MyNewComponentComponent ]      })      .compileComponents();    }));    beforeEach(() => {      fixture = TestBed.createComponent(MyNewComponentComponent);      component = fixture.componentInstance;      fixture.detectChanges();    });    it('should create', () => {      expect(component).toBeTruthy();    });  });

Edit: example with mock DummyService

  /* tslint:disable:no-unused-variable */  import { async, ComponentFixture, TestBed } from '@angular/core/testing';  import { By } from '@angular/platform-browser';  import { DebugElement } from '@angular/core';  import { RouterTestingModule } from '@angular/router/testing';  import { MyNewComponentComponent } from './my-new-component.component';  // import the service  import { DummyService } from '../dummy.service';  // mock the service  class MockDummyService extends DummyService {    // mock everything used by the component  };  describe('MyNewComponentComponent', () => {    let component: MyNewComponentComponent;    let fixture: ComponentFixture<MyNewComponentComponent>;    beforeEach(async(() => {      TestBed.configureTestingModule({        imports: [RouterTestingModule],        declarations: [MyNewComponentComponent],        providers: [{          provide: DummyService,          useClass: MockDummyService        }]      })        .compileComponents();    }));    beforeEach(() => {      fixture = TestBed.createComponent(MyNewComponentComponent);      component = fixture.componentInstance;      fixture.detectChanges();    });    it('should create', () => {      expect(component).toBeTruthy();    });  });

Add RouterTestingModule for configureTestingModule testCase

==> imports: [RouterTestingModule],

import {RouterTestingModule} from '@angular/router/testing';beforeEach(() => {TestBed.configureTestingModule({imports: [RouterTestingModule], // <====providers: [],declarations: [],});});

I get the same kind of error and I want to share my solution to help others

The Error I get in Karma

error properties: Object({ ngTempTokenPath: null, ngTokenPath: [ 'RouterModule', 'Router', 'Function', 'Function' ] })NullInjectorError: R3InjectorError(DynamicTestModule)[RouterModule -> Router -> Function -> Function]:   NullInjectorError: No provider for Function!

inventory-view.component.ts

@Component({  selector: 'app-inventory-view',  templateUrl: './inventory-view.component.html',  styleUrls: ['./inventory-view.component.scss'],  animations: []})export class InventoryViewComponent implements OnInit, AfterViewInit, OnDestroy {  constructor(    public router: Router, // <--- here was the problem    public activatedRoute: ActivatedRoute  ) { }

In my test file

inventory-view.component.spec.ts

import { HttpClientModule } from '@angular/common/http';import { waitForAsync, ComponentFixture, TestBed } from '@angular/core/testing';import { RouterTestingModule } from '@angular/router/testing';import { ActivatedRoute, convertToParamMap, Router } from '@angular/router';const ActivatedRouteSpy = {  snapshot: {    paramMap: convertToParamMap({      some: 'some',      else: 'else',    })  },  queryParamMap: of(    convertToParamMap({      some: 'some',      else: 'else',    })  )};const RouterSpy = jasmine.createSpyObj(  'Router',  ['navigate']);describe('InventoryViewComponent', () => {  let component: InventoryViewComponent;  let fixture: ComponentFixture<InventoryViewComponent>;  beforeEach(waitForAsync(() => {    TestBed.configureTestingModule({      imports: [        HttpClientModule,        RouterTestingModule,      ],      declarations: [ InventoryViewComponent ],      providers: [        { provide: ActivatedRoute,   useValue: ActivatedRouteSpy    },        { provide: Router,           useValue: RouterSpy            }      ]    })    .compileComponents();  }));  beforeEach(waitForAsync(() => {    fixture = TestBed.createComponent(InventoryViewComponent);    component = fixture.componentInstance;    fixture.detectChanges();  }));  it('should create', () => {    expect(component).toBeTruthy();  });});