public void ChangeEmployeesVehicle_ShouldChangeEmployeeVehicle()
        {
            var employee = new Employee {
                FirstName = "Ted", LastName = "Mosby", Id = 1
            };
            var vehicle = new Vehicle {
                Id = 1
            };

            var mockContext = new Mock <InstantDeliveryContext>();

            mockContext.Setup(c => c.Employees).ReturnsDbSet(employee);
            mockContext.Setup(c => c.Vehicles).ReturnsDbSet(vehicle);

            var userStore   = new Mock <UserStore <User> >(mockContext.Object);
            var userManager = new Mock <UserManager <User> >(userStore.Object);
            var controller  = new EmployeesController(mockContext.Object, userManager.Object);

            controller.ChangeVehicle(employee.Id, vehicle.Id);

            Assert.Equal(employee.Vehicle.Id, 1);
        }