How to test an Angular Factory which uses Parse SDK - angularjs

Question

This is my first question here. I'll try to do my best. I searched a lot before posting
I'm developing an angularJS application relying on the Javascript ParseSDK.
I have convinced myself to dive in testing recently, so I am a beginner.
I have this factory UserFactory that wraps around the SDK so everything is clean and modular the Angular way. ie: SDK is only used through factories (not controller nor directives).
It goes like this:
myModule.factory('UserFactory', ['$q', function($q){
var User = Parse.User.extend({
// Instance methods
},{
// static/class methods
// Overrides Parse.User.current() to wrap current User in promise
current: function(){
var deferred = $q.defer();
var currentUser = Parse.User.current();
if(currentUser)
deferred.resolve(currentUser);
else
deferred.reject("No current user");
return deferred.promise;
}
});
return User;
}]);
My question: How to test for UserFactory.current() knowing it uses an external service?
I've looked into mocking the Parse SDK but don't know how to do it since it's not angular related (ie: can't use httpBackend).
My current test file:
describe("Unit: UserFactory", function(){
var UserFactory;
beforeEach(function(){
module("myModule");
inject(function(_UserFactory_){
UserFactory = _UserFactory_;
});
});
it("should return current User", function(){
// What to expect ?
});
});
Thank you in advance

Answer 1

describe("Unit: UserFactory", function(){
var UserFactory;
beforeEach(function(){
module("myModule");
inject(function(_UserFactory_){
UserFactory = _UserFactory_;
$rootScope = _$rootScope_;
});
});
describe('current()', function() {
var successCallback, errorCallback;
beforeEach(function() {
successCallback = jasmine.createSpy('success');
errorCallback = jasmine.createSpy('error');
});
it("promise should resolve if Parse.User.current is truthy", function(){
spyOn(Parse.User, 'current').and.returnValue(true);
UserFactory.current().then(successCallback, errorCallback);
$rootScope.$digest();
expect(successCallback.calls.count()).toBe(1);
expect(errorCallback.calls.count()).toBe(0);
expect(Parse.User.current).toHaveCalledOnce();
});
it("promise should reject if Parse.User.current is falsy", function(){
spyOn(Parse.User, 'current').and.returnValue(false);
UserFactory.current().then(successCallback, errorCallback);
$rootScope.$digest();
expect(errorCallback.calls.count()).toBe(1);
expect(successCallback.calls.count()).toBe(0);
expect(Parse.User.current).toHaveCalledOnce();
});
});
});