public void AuditoriumService_DeleteAuditoriumByCinemaId_SeatServiceReturnsNull_ReturnsNull() { //Arrange List <Auditorium> auditoriumsModelsList = new List <Auditorium>(); auditoriumsModelsList.Add(_auditorium); IEnumerable <Auditorium> auditoriums = auditoriumsModelsList; Task <IEnumerable <Auditorium> > responseTask = Task.FromResult(auditoriums); int expectedCount = 1; List <ProjectionDomainModel> projectionsModelsList = new List <ProjectionDomainModel>(); projectionsModelsList.Add(_projectionDomainModel); IEnumerable <ProjectionDomainModel> projections = projectionsModelsList; Task <IEnumerable <ProjectionDomainModel> > projectionsResponseTask = Task.FromResult(projections); IEnumerable <SeatDomainModel> seats = null; Task <IEnumerable <SeatDomainModel> > seatsResponseTask = Task.FromResult(seats); AuditoriumService auditoriumService = new AuditoriumService(_mockAuditoriumsRepository.Object, _mockProjectionService.Object, _mockSeatService.Object); _mockProjectionService.Setup(x => x.DeleteByAuditoriumId(It.IsAny <int>())).Returns(projectionsResponseTask); _mockSeatService.Setup(x => x.DeleteByAuditoriumId(It.IsAny <int>())).Returns(seatsResponseTask); _mockAuditoriumsRepository.Setup(x => x.GetByCinemaId(It.IsAny <int>())).Returns(responseTask); _mockAuditoriumsRepository.Setup(x => x.Delete(It.IsAny <int>())).Returns(_auditorium); //Act var result = auditoriumService.DeleteAuditoriumsByCinemaId(_auditorium.CinemaId).ConfigureAwait(false).GetAwaiter().GetResult(); //Assert Assert.IsNull(result); }