public async void CreateNewBill_OkResult()
{
// Arrange
int residentId = 1, apartmentId = 1;
Mock <GenericRepository <Bill> > mockBillRepository = new Mock <GenericRepository <Bill> >();
Mock <UserRepository> mockUserRepository = new Mock <UserRepository>();
Mock <ApartmentRepository> mockApartmentRepository = new Mock <ApartmentRepository>();
Mock <GenericRepository <Notification> > mockNotificationRepository = new Mock <GenericRepository <Notification> >();
Mock <IUnitOfWork> mockIUnitOfWork = new Mock <IUnitOfWork>();
mockIUnitOfWork
.Setup(u => u.GetRepository <Bill, GenericRepository <Bill> >())
.Returns(mockBillRepository.Object);
mockIUnitOfWork
.Setup(u => u.GetRepository <User, UserRepository>())
.Returns(mockUserRepository.Object);
mockIUnitOfWork
.Setup(u => u.GetRepository <Apartment, ApartmentRepository>())
.Returns(mockApartmentRepository.Object);
mockIUnitOfWork
.Setup(u => u.GetRepository <Notification, GenericRepository <Notification> >())
.Returns(mockNotificationRepository.Object);
BillsController controller = new BillsController(mockIUnitOfWork.Object);
// Act
IActionResult result = await controller.CreateNewBill(residentId, apartmentId, new DateTime());
// Assert
Assert.NotNull(result);
Assert.IsType <OkResult>(result);
}