someone hep me to solve unit testing login angularJS

My code of login.js is

var loginModule = angular.module('loginModule', [])
        .controller('LoginCtrl', function ($scope, $auth, $location) {
            if (!$auth.isAuthenticated()) {
                $scope.oneAtATime = true;
                $scope.login = function () {
                    $auth.login({userName: $scope.username, password: $scope.password, isEncript: false})
                            .then(function () {
                                console.log($auth.getMessage());
                            })
                            .catch(function (response) {
                                console.log(response);
                            });
                };
            }
            else {
                $location.path('/home');
            }

            $scope.status = 'true';

        });

and unit test code is

describe('login()', function() {

        it('should be able to handle login errors', function () {
            var user = {
                email: 'foo@bar.com',
                password: '1234',
                isEncript: false
            };

            this.$httpBackend.expectPOST('app/controller/apicall.php?serviceName=login').respond(200);

            this.$auth.login(user).then(angular.noop, function () {

            });

           this.$httpBackend.flush();

            expect(user.isEncript).toBe(false);
        });
    });

});

......................the error i am getting is below .......................................

$auth login() should be able to handle login errors FAILED
    Error: Unexpected request: POST ../../controller/apicall.php?serviceName=login
    Expected POST /app/controller/apicall.php?serviceName=login

help me to solve how should i solve this error please help me i am new in angular and in unit testing.