AngularJS controller instantiation in unit tests - functions not binding to scope values - angularjs

I have a service that synchronously returns data to a controller:
angular.module('app').controller(function($scope, myService) {
$scope.foo = myService.getFoo();
});
This works just fine in the browser. In my unit tests, $scope.foo is undefined:
beforeEach(function () {
module('app');
myService = jasmine.createSpyObj('myService', ['getFoo']);
inject(function($controller, $rootScope) {
$scope = $rootScope.$new();
ctrl = $controller('ModelSliderCtrl', {
myService: myService,
$scope: $scope
});
});
});
it('should have foo on the scope', function() {
myService.getFoo.and.returnValue({});
expect(myService.getFoo).toHaveBeenCalled(); // PASS
$scope.$digest();
expect($scope.foo).toBeDefined(); // FAIL - $scope.foo is undefined
});
This does work in both the browser and tests:
angular.module('app').controller(function($scope, myService) {
$scope.init = function() {
$scope.foo = myService.getFoo();
};
$scope.init();
});
.
it('should have foo on the scope', function() {
myService.getFoo.and.returnValue({});
$scope.init();
expect(myService.getFoo).toHaveBeenCalled(); // PASS
expect($scope.foo).toBeDefined(); // PASS
});
I'd like to believe I'm fairly well-versed in Angular, Jasmine and JavaScript. I've also asked some colleagues who are equally puzzled.
Can anyone explain to me what is going on here?

You are setting up a mock
it('should have foo on the scope', function() {
myService.getFoo.and.returnValue({});
after your controller has been instantiated. It's too late to set up the mock by then, do it before instantiating your controller since you are executing init() right away.
myService = jasmine.createSpyObj('myService', ['getFoo']);
myService.getFoo.and.returnValue({});
inject(function($controller, $rootScope) {

Related

how to test function in controller scope executed by event

function in controller:
angular.module('myApp').controller('MyController', function(){
$scope.f = function($event){
$event.preventDefault();
//logic
return data;
}
})
describe('MyController', function(){
'use strict';
var MyController,
$scope;
beforeEach(module('myApp'));
beforeEach($inject(function($rootScope, $controller){
$scope = $rootScope.$new();
MyController = $controller('MyController', {
$scope: $scope
})
}));
})
it('should...', function(){
//fire event and expect data
})
$scope.f function is used in directive, it can be executed by ng-click="f($event)"
what is right way for fire event in unit test?
Short Answer
You don't need to fire the event. You have access to the scope, which has the function you want to test. This means you just execute the function, then assert. It will look something like this:
it('should call preventDefault on the given event', function(){
var testEvent = $.Event('someEvent');
$scope.f(testEvent);
expect(testEvent.isDefaultPrevented()).toBe(true);
});
See the following:
jQuery Event Object
event.isDefaultPrevented()
Full Spec
Also - your it block should be inside your describe block, so that it has access to the $scope field. It should look more like this:
describe('MyController', function(){
'use strict';
var MyController,
$scope;
beforeEach(module('myApp'));
beforeEach($inject(function($rootScope, $controller){
$scope = $rootScope.$new();
MyController = $controller('MyController', {
$scope: $scope
})
}));
it('should call preventDefault on the given event', function(){
var testEvent = $.Event('someEvent');
$scope.f(testEvent);
expect(testEvent.isDefaultPrevented()).toBe(true);
});
})
A Note About Structure
Don't be afraid to use the describe blocks to structure your tests. Imagine you had another function on the $scope called f2, then you would probably want to partition your spec file up more like this:
describe('MyController', function(){
'use strict';
var MyController,
$scope;
beforeEach(module('myApp'));
beforeEach($inject(function($rootScope, $controller){
$scope = $rootScope.$new();
MyController = $controller('MyController', {
$scope: $scope
})
}));
describe('$scope', function() {
describe('.f()', function() {
// tests related to only the .f() function
});
describe('.f2()', function() {
// tests related to only the .f2() function
});
});
})
This has the benefit that when a test fails, the error message you see is constructed based on the hierarchy of describe blocks. So it would be something like:
MyController $scope .f() should call preventDefault on the given
event

jasimine argument scope is required when instantiating a controller

I am working to initiate a controller sits inside a directive. I have some tests I need to run but right now I am not able to access the controller with ng-Mock.
describe('hero Directive', function () {
var $compile,
$rootScope,
$scope,
element,
ctrl;
beforeEach(function () {
angular.mock.module('ha.module.core');
angular.mock.inject(function (_$compile_, _$rootScope_, _$controller_, $templateCache) {
$compile = _$compile_;
element = angular.element("<div exlore-hereo></div");
$compile(element)($rootScope);
$rootScope = _$rootScope_;
$scope = $rootScope.$new();
ctrl = _$controller_('ExploreHeroController', { $scope: $scope });
console.log(ctrl)
$scope.$digest();
});
});
afterEach(function () {
// need to remove the element element.remove();
});
describe('directive controller', function () {
it('should dispatch call $emit with $methodsBound', function () {
//spyOn($scope, '$emit');
spyOn($scope, 'ControllerName');
//expect(scope.$emit).toHaveBeenCalledWith('$methodsBound');
//expect(ctrl).toHaveBeenCalled();
});
});
});
I created an element compiled it and called the $digest method.
The error that I got was
Argument 'scope' is required.
So I tried spying on the it with jasmine
spyON($scope, 'ControllerName');
My controller inside of my directive is pretty basic.
var ControllerName = function($scope) {
$scope.$emit('$method');
}
It seems like I need a spy, but I am not sure why the one I created does not work.
You can try to spy on $scope, but note that ControllerName is not a member of the $scope object.
However, $emit is....
The thing is, that you call $emit in the controllers constructos, therefore you have to spy on it before:
beforeEach(function () {
...
$scope = $rootScope.$new();
spyOn($scope, '$emit');
ctrl = _$controller_('ExploreHeroController', { $scope: $scope });
...
});
describe('directive controller', function () {
it('should dispatch call $emit with $methodsBound', function () {
expect($scope.$emit).toHaveBeenCalledWith('$methodsBound');
});
});

Should Angular Service Execute In Unit Test

I am trying to integrate Karma and Jasmine in to my project.
I have started off with a very basic test to ensure my controller is defined and a $scope variable equals a string - which pass as expected.
My controller, also calls a service which performed a $http.get, when running my test, without any mention of a service, i get the error:
Error: Unexpected request: GET /my/endpoint/
No more request expected
Controller:
define(['module'], function (module) {
'use strict';
var MyController = function ($scope, MyService) {
$scope.testScope = 'karma is working!';
MyService.getData().then(function (data) {
$scope.result = data.hour
});
};
module.exports = ['$scope', 'MyService', MyController ];
});
Test:
define(['require', 'angular-mocks'], function (require) {
'use strict';
var angular = require('angular');
describe("<- MyController Spec ->", function () {
var controller, scope;
beforeEach(angular.mock.module('myApp'));
beforeEach(inject(function (_$controller_, _$rootScope_) {
scope = _$rootScope_.$new();
controller = _$controller_('MyController', {$scope: scope});
scope.$apply();
}));
it('should verify that the controller exists ', function() {
expect(controller).toBeDefined();
});
it('should have testScope scope equaling *karma is working*', function() {
expect(scope.testScope ).toEqual('karma is working!');
});
});
});
Are the above errors expected?
UPDATE from response below:
define(['require', 'angular-mocks'], function (require) {
'use strict';
var angular = require('angular');
describe("<- MyController Spec ->", function () {
var controller, scope, $httpBackend, myService;
beforeEach(angular.mock.module('myApp'));
beforeEach(inject(function (_$controller_, _$rootScope_, _$httpBackend_, _myService_) {
scope = _$rootScope_.$new();
$httpBackend = _$httpBackend_;
$httpBackend.expectGET("/my/endpoint");
controller = _$controller_('MyController', {$scope: scope});
scope.$apply();
}));
it('should verify that the controller exists ', function() {
expect(controller).toBeDefined();
});
it('should have testScope scope equaling *karma is working*', function() {
expect(scope.testScope ).toEqual('karma is working!');
});
});
});
Using Angular Mocks you will always get an error if there is an unexpected or incorrect http request attempted -- even for templates. In your case there are two ways to handle this for testing:
use $httpBackend
$httpBackend was designed for testing http requests without actually hitting the wire. In your test, simply add
$httpBackend.expectGET("/my/endpoint");
before you initialize the controller.
Mock the service
The service itself is making the http request, so you can mock the service instead. Services will be injected automatically as usual, but you can explicitly injection whatever you want:
controller = _$controller_('MyController', {$scope: scope,
MyService: {getData: () => ({then: () => {}}) });
This injects an object that has a getData function which returns an object with .then function. Of course this doesn't come close to implementing what you are trying to do, but it is another way to perform the test.
Both of the above approaches are valid. It depends on what you are testing and what you are trying to accomplish with the testing.

Mocking a service dependency in an Angular controller with jasmine

I've been trying to get started with unit testing in angular with karma and jasmine, and i've been pulling my hair out trying to wrap my head around how to test controllers with dependencies. I tried mocking a spy with a jasmine spyObj and registering it in the beforeEach hook, but for some reason the spy isn't being recognized.
Here's the code:
angular.module('testModule', [])
.controller('TestController', [
'$scope',
'TestService',
function ($scope, TestService) {
$scope.data = TestService.load();
}])
.factory('TestService', function () {
return {
load: function(){
return "foo";
}
}
});
and here's the test
describe('TestController', function() {
var $controller, $scope, TestService;
beforeEach(module('testModule'), function($provide){
TestService = jasmine.createSpyObj("TestService", ["load"]);
TestService.load.andReturn("bar");
$provide.value("TestService", TestService)
});
beforeEach(inject(function(_$controller_, $rootScope, _TestService_) {
$scope = $rootScope.$new();
TestService = _TestService_;
$controller = _$controller_('TestController', {
$scope: $scope,
TestService: TestService
});
}));
it('should set $scope.data to bar when TestService.load is called', function() {
expect(TestService.load).toHaveBeenCalled();
expect($scope.data).toEqual("bar");
}); });
Both assertions in the test fail.
I get 'Error: Expected a spy, but got Function' when i call expect(TestService.load).toHaveBeenCalled();
and if I call expect($scope.data).toEqual("bar"), I get Expected 'foo' to equal 'bar'. "Foo" is coming from the actual service, not the spy object.
Thanks for your help.
Instead of jasmine.createSpyObj, it will be easier to use the existing service that the $injector provides and then just mock the single method. You can achieve this with spyOn instead:
describe('TestController', function() {
var $controller, $scope, TestService;
beforeEach(module('testModule'));
beforeEach(inject(function(_$controller_, $rootScope, _TestService_) {
$scope = $rootScope.$new();
TestService = _TestService_;
spyOn(TestService, 'load').and.returnValue('bar');
$controller = _$controller_('TestController', {
$scope: $scope,
TestService: TestService
});
}));
it('should set $scope.data to bar when TestService.load is called', function() {
expect(TestService.load).toHaveBeenCalled();
expect($scope.data).toEqual("bar");
});
});
In your beforeEach you are injecting in _TestService_ and then overwriting the one you declared in the previous beforeEach via:
TestService = _TestService_;
Remove that code and your test should succeed.
Also there is no need to do this:
$provide.value("TestService", TestService)
Basically you're trying to use Angular's dependency injection when you're manually injecting things which is unnecessary.

Mocking $routeParams in a test in order to change its attributes dynamically

I have a controller test that depends on the Angular $routeParams service:
var $routeParams, MainCtrl, scope;
beforeEach(inject(function ($controller, $rootScope, $injector, $templateCache) {
scope = $rootScope.$new();
$routeParams = $injector.get('$routeParamsMock');
MainCtrl = $controller('MainCtrl', {
$scope: scope,
$routeParams: $routeParams,
});
}));
it('should load a pg from $routeParams', function(){
scope.userData = {};
$routeParams._setPg('PG_FIRST');
scope.$digest();
timeout.flush();
expect(scope.userData.pg).toBe(0);
$routeParams._setPg('PG_SECOND');
scope.$digest();
timeout.flush();
expect(scope.userData.pg).toBe(1);
});
$routeParamsMock:
!(function(window, angular){
'use strict';
angular.module('vitaApp')
.service('$routeParamsMock', function() {
var _pg = null;
return{
pg: _pg,
_setPg: function(pg){
_pg = pg;
}
}
});
})(window, window.angular);
When debugging the test, I was surprised to find out that $routeParamsMock.pg was returning null every single time, even though I called _setPg with a different value.
Is it because null is considered a primitive (with a type of object...), and thus passed by value?, or perhaps because Angular is copying the object that is passed to the $controller service?.
The solution I am looking for is preferably one that won't require to instanciate different controllers per different test scenerios.
eg:
MainCtrl = $controller('MainCtrl', {
$scope: scope,
$routeParams: {'pg': 'PG_FIRST'},
});
MainCtrl = $controller('MainCtrl', {
$scope: scope,
$routeParams: {'pg': 'PG_SECOND'},
});
The thing is, what you don't want to do, is probably the best solution you have. A mock makes sense when what you want to mock is kinda complex. Complex dependency with methods, lot of states, etc. For a simple object like $routeParams it makes all the sense of the world to just pass a dummy object to it. Yes it would require to instantiate different controllers per test, but so what?
Structure your tests in a way that makes sense, makes it readable and easy to follow.
I suggest you something like:
describe('Controller: Foo', function() {
var $controller, $scope;
beforeEach(function() {
module('app');
inject(function($rootScope, _$controller_) {
$scope = $rootScope.$new();routeParams = {};
$controller = _$controller_;
});
});
describe('With PG_FIRST', function() {
beforeEach(function() {
$controller('Foo', { $scope: $scope, $routeParams: {'PG': 'PG_FIRST'}});
});
it('Should ....', function() {
expect($scope.something).toBe('PG_FIRST');
});
});
describe('With PG_SECOND', function() {
beforeEach(function() {
$controller('Foo', { $scope: $scope, $routeParams: {'PG': 'PG_SECOND'}});
});
it('Should ....', function() {
expect($scope.something).toBe('PG_SECOND');
});
});
});
With a good test organization, I can say that I like this test easy to follow.
http://plnkr.co/edit/5Q3ykv9ZB7PuGFMfWVY5?p=preview

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