Cannot read property 'subscribe' of undefined in unit test

[Can Altıniğne]

I have a component file as shown below

import { Component, OnInit, Input } from '@angular/core';

import { Router, ActivatedRoute, Params } from '@angular/router';

import { InstanceService } from '../../theme/services/instance-service';

@Component({

selector: 'instance',

styleUrls: ['./instance.scss'],

templateUrl: './instance.html'

})

export class InstanceComponent implements OnInit {

db_name: String;

data: Object;

constructor(private route: ActivatedRoute, private router: Router, private instanceService: InstanceService ) {

}

ngOnInit() {

this.route.params.subscribe((params: Params) => {

this.db_name = params['id'];

});

this.instanceService.getInstances().subscribe((res) => {

this.data = res.find(x => x.db_name === this.db_name);

});

}

}

Also there is a spec file for unit tests but I can not create component successfully. It gives an error which says 'Cannot read property 'subscribe' of undefined'. How can I solve this ?

import { async, ComponentFixture, TestBed } from '@angular/core/testing';

import { Ng2SmartTableModule } from 'ng2-smart-table';

import { InstanceComponent } from './instance.component';

import { Router, ActivatedRoute } from '@angular/router';

import { InstanceService } from '../../theme/services/instance-service';

import { HttpModule } from '@angular/http';

import { Observable, Subject } from 'rxjs/Rx';

import { RouterTestingModule } from '@angular/router/testing';

import { BehaviorSubject } from 'rxjs/BehaviorSubject';

import 'rxjs/Rx';

import { Subscription } from 'rxjs/Subscription';

class InstanceServiceStub {

getInstances() {

return Observable.empty();

}

}

describe('InstanceComponent', () => {

let component: InstanceComponent;

let fixture: ComponentFixture<InstanceComponent>;

beforeEach(async(() => {

TestBed.configureTestingModule({

imports: [HttpModule],

declarations: [InstanceComponent],

providers: [{ provide: ActivatedRoute, useValue: { data: Observable.of({ name: 'pinocho' })}},

{ provide: Router },

{ provide: InstanceService, useClass: InstanceServiceStub }],

})

.compileComponents();

}));

beforeEach(() => {

fixture = TestBed.createComponent(InstanceComponent);

component = fixture.componentInstance;

fixture.detectChanges();

});

it('should be created', () => {

expect(component).toBeTruthy();

});

});

[Kyle Thomas]

I have a RouterLinkStubDirective, etc. provided by Google

describe('LoginComponent', async() => {
    let mockAuthenticationService: MockAuthenticationService;
    let mockActivatedRouter: MockActivatedRoute;
    let mockRouter: MockRouter;
    let comp: LoginComponent;
    let fixture: ComponentFixture<LoginComponent>;
    let mockReturnsService: MockReturnsService;

    beforeEach(() => {
        mockAuthenticationService = new MockAuthenticationService();
        mockActivatedRouter = new MockActivatedRoute({ref: 'framedream'});
        mockRouter = new MockRouter();
        mockReturnsService = new MockReturnsService();

        TestBed.configureTestingModule({
            declarations: [LoginComponent,
                RouterLinkStubDirective, RouterLinkActiveStubDirective, RouterOutletStubComponent],
            imports: [
                FormsModule,
                MdButtonModule, MdCardModule, MdIconModule,
                FlexLayoutModule,
                CovalentLayoutModule, CovalentLoadingModule,
                HttpModule, BrowserAnimationsModule],
            providers: [
                MdIconRegistry,
                {provide: ReturnsService, useValue: mockReturnsService},
                {provide: AuthenticationService, useValue: mockAuthenticationService},
                {provide: ActivatedRoute, useValue: mockActivatedRouter},
                {provide: Router, useValue: mockRouter},
                Helper,
                TdLoadingService,
            ],
            schemas: [CUSTOM_ELEMENTS_SCHEMA]
        })
        // Get rid of app's Router configuration otherwise many failures.
        // Doing so removes Router declarations; add the Router stubs
            .overrideModule(AppModule, {
                add: {
                    declarations: [RouterLinkStubDirective, RouterLinkActiveStubDirective, RouterOutletStubComponent]
                }
            })
            .compileComponents();
    });