public async void ByMachineGuid_Not_Exists() { var mock = new ServiceMockFacade <IMachineService, IMachineRepository>(); mock.RepositoryMock.Setup(x => x.ByMachineGuid(It.IsAny <Guid>())).Returns(Task.FromResult <Machine>(null)); var service = new MachineService(mock.LoggerMock.Object, mock.MediatorMock.Object, mock.RepositoryMock.Object, mock.ModelValidatorMockFactory.MachineModelValidatorMock.Object, mock.DALMapperMockFactory.DALMachineMapperMock, mock.DALMapperMockFactory.DALLinkMapperMock); ApiMachineServerResponseModel response = await service.ByMachineGuid(default(Guid)); response.Should().BeNull(); mock.RepositoryMock.Verify(x => x.ByMachineGuid(It.IsAny <Guid>())); }