public async void ByProductID_Not_Exists() { var mock = new ServiceMockFacade <IWorkOrderRepository>(); mock.RepositoryMock.Setup(x => x.ByProductID(It.IsAny <int>(), It.IsAny <int>(), It.IsAny <int>())).Returns(Task.FromResult <List <WorkOrder> >(new List <WorkOrder>())); var service = new WorkOrderService(mock.LoggerMock.Object, mock.RepositoryMock.Object, mock.ModelValidatorMockFactory.WorkOrderModelValidatorMock.Object, mock.BOLMapperMockFactory.BOLWorkOrderMapperMock, mock.DALMapperMockFactory.DALWorkOrderMapperMock, mock.BOLMapperMockFactory.BOLWorkOrderRoutingMapperMock, mock.DALMapperMockFactory.DALWorkOrderRoutingMapperMock); List <ApiWorkOrderResponseModel> response = await service.ByProductID(default(int)); response.Should().BeEmpty(); mock.RepositoryMock.Verify(x => x.ByProductID(It.IsAny <int>(), It.IsAny <int>(), It.IsAny <int>())); }