code coverage for angularJS service - angularjs

Question

I have a controller that is calling a service. I want to write my unit tests such that I get coverage on the success and error functions of the then function.
maApp.controller('editEmailAndPasswordController',
["$scope", "emailAndPasswordService",
function editEmailAndPasswordController($scope, emailAndPasswordService) {
$scope.EmailId = 'as#as.com';
$scope.CurrentPassword = '';
$scope.Success = false;
$scope.save = function () {
var request = {
currentPassword: $scope.CurrentPassword,
newEmailId: $scope.EmailId
};
emailAndPasswordService.save(request).then(function (data) {
$scope.Success = true;
}, function (data, status, header, config) {
$scope.Success = false;
});
};
}]);
This is what I have got so for. I want another test for the fail condition as well, but not sure how to set up the mock service.
describe('Controllers', function () {
var $scope, ctrl, controller, svc, def;
describe('editEmailAndPasswordController', function () {
beforeEach(function() {
module('maApp');
});
beforeEach(inject(function ($controller, $rootScope, $q) {
ctrl = $controller;
svc = {
save: function () {
def = $q.defer();
return def.promise;
}
};
spyOn(svc, 'save').andCallThrough();
$scope = $rootScope.$new();
controller = ctrl('editEmailAndPasswordController', { $scope: $scope, emailAndPasswordService: svc });
}));
it('should set ShowEdit as false upon save', function () {
$scope.ShowEdit = true;
$scope.EmailId = 'newEmail';
$scope.CurrentPassword = 'asdf1';
$scope.save();
expect($scope.EmailId).toBe('as#as.com');
expect($scope.Success).toBe(true);
});
});
});

Answer 1

You have some real problems with this code.
Don't call ".andCallThrough()"- that way your test depends on the implementaton of the service and means your controller is not isolated. The main idea is to create unit tests.
svc = {save: jasmine.createSpy()};
svc.save.andReturn(...);
You can't assert against expect($scope.EmailId).toBe('as#as.com'); because you change the value in the code to $scope.EmailId = 'newEmail';
you can create 2 private methods for readability
function success(value) {
var defer = q.defer();
defer.resolve(value);
return defer.promise;
}
function failure(value){
var defer = q.defer();
defer.reject(value);
return defer.promise;
}
Thus in the first test you can call
svc.save.andReturn(success());
$scope.$digest()
expect($scope.Success).toBeTruthy();
And in the other test you will have the same but:
svc.save.andReturn(failure());
$scope.$digest()
expect($scope.Success).toBeFalsy();

Answer 2

In one case, you want the promise to be successful, so you want to resolve the deferred:
$scope.save();
def.resolve('whatever');
$scope.$apply();
expect($scope.Success).toBe(true);
...
In the other case, you want the promise to be a failure, so uou want to reject the deferred:
$scope.save();
def.reject('whatever');
$scope.$apply();
expect($scope.Success).toBe(false);
...
This is explained in the documentation.