Unit testing with private service injected using jasmine angular2

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I have a problem trying to unit test an angular service. I want to verify that this service is properly calling another service that is injected into it.

Lets say I have this ServiceToTest that injects ServiceInjected:

ServiceToTest .service.ts

export class ServiceToTest  {
    constructor(private _si: ServiceInjected) {}
    public init() {


You don't spy on the service tied to your TestBed. Get the service from your Testbed

beforeEach(() => {
    providers: [ServiceToTest ,
      { provide: ServiceInjected, useValue: serviceInjectedStub }]
  injectedService = TestBed.get(ServiceInjected);

And test on it

spyOn(injectedService, 'configure').and.returnValue(/* return same data type here */);
// ...

Testing Dependency Injection • Angular, Unit testing with private service injected using jasmine angular2 - angular. _si. configure(); } } ServiceInjected.service.ts #Injectable() export class� Working with unit testing on any project that at least tries to be serious is a must, it doesn’t matter if you choose to use a TDD (test-driven development) approach or not you are going to have

Or you can use jasmine.createSpyObj and provide it with useValue like bellow:

describe('YourComponent', () => {

  let serviceInjectedSpy: jasmine.SpyObj<ServiceInjected>;

  beforeEach(async(() => {

     // notice here
     serviceInjectedSpy = jasmine.createSpyObj('ServiceInjected', ['configure']);

        declarations: [YourComponent],
        providers: [
           {provide: ServiceInjected, useValue: serviceInjectedSpy}
        imports: [
     }).compileComponents().then(() => {
        fixture = TestBed.createComponent(YourComponent);
        component = fixture.componentInstance;

  it('should assert my test', () => {
       serviceInjectedSpy.configure.and.returnValue(/* what you want */);


Testing Angular 2 HTTP Services with Jasmine, This tutorial will show you how to test HTTP requests in Angular 2. Angular 2 depends heavily on Dependency Injection (DI) to inside the constructor and store it automatically with the private keyword. With the Now that we've added the assertions, our first unit test against an Http service is complete. The rest of the dependencies are mainly reporters for our tests, tools to use karma and jasmine and browser launcher. Creating and Testing Services. To test the service first we need to create a service component using below command: “`ng generate service data“` The above command states that it will generate the new service name dataService.

Use this:

spyOn(serviceInjectedStub, 'configure').and.returnValue(config); // config is a mock

Testing Services in Angular 2 - Semaphore Tutorial, In this article, we'll explore how to use a test-driven development (TDD) approach Next, we declare the class we're exporting and a private variable to hold the list of You've successfully unit tested your first Angular 2 service. import { Injectable } from '@angular/core'; // added import { FormData } from '. Up-to-date version of Angular — Unit Testing recipes. Read it to learn about the latest Angular APIs. Keep reading to see the old versions of the testing API. The Jasmine section and custom

You should use a mock service like:

class MockAuthService extends AuthService {
  isAuthenticated() {
    return 'Mocked';

In this way you have control over the service that you are not testing and focus on the other.

Now, to check if the service is being called correctly maybe you can add a mock variable that is turned to true whenever the mock service is called.

Testing services, @Injectable() export class MasterService { constructor(private valueService: ValueService) These standard testing techniques are great for unit testing services in isolation. SpyObj<ValueService>; beforeEach(() => { const spy = jasmine. Testing the service. When writing unit tests with Jasmine, every test spec is written as an it() block, where an assertion is made and then checked if that assertion is true or not. We won’t go into too much detail here, since there’s a lot of documentation for Jasmine out there. We want to test if our VideoService returns an Observable

Testing, Missing @Injectable() Decorators The ng test command builds the app in watch mode, and launches the Karma test runner. You can also unit test an Angular app with other testing libraries and test runners. There are paid CI services like Circle CI and Travis CI, and you can also host your own for free using Jenkins� The testing documentation offers tips and techniques for unit and integration testing Angular applications through a sample application created with the Angular CLI.This sample application is much like the one in the Tour of Heroes tutorial.

Angular Testing: Using Spies, Jasmine spies are used to track or stub functions or methods. We can use spies to test components that depend on a service and avoid Let's use an example very similar to what we used in our introduction to unit tests in Angular. import { Injectable } from '@angular/core'; @Injectable() export class� The Angular team recommends putting unit test scripts alongside the files they are testing and using a .spec filename extension to mark it as a testing script (this is a Jasmine convention).

Chapter 9. Unit-testing Angular applications, The basics of unit testing with the Jasmine framework; The main artifacts from the You can inject the service into it() using inject() to test synchronous functions in private urlBase: string, @Inject(WEATHER_URL_SUFFIX) private urlSuffix:� We can resolve dependencies in our tests using a number of methods. We can resolve using the the test bed itself, usually in the beforeEach function and store the resolved dependencies for use in our test specs. We can resolve using the inject function at the start of each test spec. We can also …

  • See github.com/angular/angular/issues/10788. You could simply inject the real service and spy on it. Or not use DI at all and use new ServiceToTest(stub) to test the service. Or use useFactory as explained in the issue.
  • Thx dude !! Holiday's at 17h for me today ! :p
  • No problem, enjoy them :D
  • this is an important piece of information I was missing, thanks mate
  • @amansinghgusain as a side note, you're not forced to use the Test bed to get it, you can simply use the array notation in your component : injectedService = component['myService']. Works even with private attributes
  • For some reason this didn't work for me. I still get that the service was not called and it certainly gets called in ngOnInit.