Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

Getting Unknown Provider error when injecting a Service into an Angular unit test

I'm fairly new to Angular and have reviewed all the similarly related questions on Stack Overflow but none have helped me. I believe I have everything set up correctly but am still getting an 'Unknown Provider' error when attempting to inject a service into a unit test. I have laid out my code below - hopefully someone can spot an obvious error!

I define my modules in a seperate .js file like this:

angular.module('dashboard.services', []); angular.module('dashboard.controllers', []); 

Here is where I define a service called EventingService (with logic removed for brevity):

angular.module('dashboard.services').factory('EventingService', [function () {     //Service logic here }]); 

Here is my controller that uses the EventingService (this all works fine at runtime):

angular.module('dashboard.controllers')     .controller('Browse', ['$scope', 'EventingService', function ($scope, eventing) {         //Controller logic here }]); 

Here is my unit test - its the line where I attempt to inject the EventingService that causes an error when I run the unit test:

describe('Browse Controller Tests.', function () {     beforeEach(function () {         module('dashboard.services');         module('dashboard.controllers');     });      var controller, scope, eventingService;      beforeEach(inject(function ($controller, $rootScope, EventingService) {         scope = $rootScope.$new();         eventingService = EventingService          controller = $controller('Browse', {             $scope: scope,             eventing: eventingService         });     }));       it('Expect True to be True', function () {         expect(true).toBe(true);     }); }); 

When I run the test I get this error:

Error: Unknown provider: EventingServiceProvider <- EventingService

I have ensured that my jasmine specrunner.html file has all the necessary source files (this is an Asp.Net MVC project):

<!-- Include source files here... --> @Scripts.Render("~/bundles/jquery") <script type="text/javascript" src="@Url.Content("~/Scripts/angular.js")"></script>   <script type="text/javascript" src="@Url.Content("~/Scripts/angular-mocks.js")"></script>                   <script type="text/javascript" src="@Url.Content("~/App/scripts/app.js")"></script>                       <!-- Angular modules defined in here --> <script type="text/javascript" src="@Url.Content("~/App/scripts/services/eventing.js")"></script>         <!-- My Eventing service defined here -->   <script type="text/javascript" src="@Url.Content("~/App/scripts/controllers/browse.js")"></script>        <!-- My Browse controller defined here -->  <!-- Include spec files here... --> <script type="text/javascript" src="@Url.Content("~/App/tests/browse.js")"></script>                      <!-- The actual unit test here --> 

I just can not fathom why Angular is throwing this error complaining about my EventingService. My controller works fine at runtime - it's just when I try to test it that I am getting an error so I am curious as to whether I have screwed something up with the mocking/injection.

The Angular help on testing is rubbish so I am stumped at present - any help or suggestions anyone can give would be very appreciated. Thanks.

like image 982
Dud Avatar asked Apr 04 '13 09:04

Dud


People also ask

What is the best unit testing framework for Angular?

Jasmine is the default test framework used with Angular. It ships with Angular CLI by default. With such low friction required to use it, it's not surprising so many people adopt it.

What is beforeEach in Angular testing?

beforeEach is a global function in Jasmine that runs some setup code before each spec in the test suite. In this test suite, beforeEach is used to create a testing module using the TestBed object and declares any components that would be used in this testing module.

What does fixture detectChanges () do?

fixture. detectChanges() tells Angular to run change-detection. Finally! Every time it is called, it updates data bindings like ng-if, and re-renders the component based on the updated data. Calling this function will cause ngOnInit to run only the first time it is called.


2 Answers

I just ran into this and solved it by switching to getting the service using the $injector explicitly:

var EventingService, $rootScope; beforeEach(inject(function($injector) {   EventingService = $injector.get('EventingService');   $rootScope = $injector.get('$rootScope'); })); 

I wish I could tell you why this works and why the simple

beforeEach(inject(function(EventingService) {   ....  })); 

does not, but I don't have the time to investigate the internals. Always best to use one coding style and stick to it.

This style is better in that the name of the variable that you use in your tests is the correct name of the Service. But it is a bit verbose.

There is another angular magic feature that uses strange variable names like $rootScope but I don't like the hacky look of that.

Note that the most of the time people get this error because they didn't include the modules:

beforeEach(module('capsuling')); beforeEach(module('capsuling.capsules.services')); 
like image 63
Chris Sattinger Avatar answered Oct 04 '22 12:10

Chris Sattinger


If your controllers (defined under dashboard.controllers module) depend on some services which are enclosed in different module (dashboard.services) than you need to reference the dependency modules in your module signature:

angular.module('dashboard.services', []); angular.module('dashboard.controllers', ['dashboard.services']); 
like image 44
Stewie Avatar answered Oct 04 '22 10:10

Stewie