public async void All() { var mock = new ServiceMockFacade <IVendorRepository>(); var records = new List <Vendor>(); records.Add(new Vendor()); mock.RepositoryMock.Setup(x => x.All(It.IsAny <int>(), It.IsAny <int>())).Returns(Task.FromResult(records)); var service = new VendorService(mock.LoggerMock.Object, mock.RepositoryMock.Object, mock.ModelValidatorMockFactory.VendorModelValidatorMock.Object, mock.BOLMapperMockFactory.BOLVendorMapperMock, mock.DALMapperMockFactory.DALVendorMapperMock, mock.BOLMapperMockFactory.BOLProductVendorMapperMock, mock.DALMapperMockFactory.DALProductVendorMapperMock, mock.BOLMapperMockFactory.BOLPurchaseOrderHeaderMapperMock, mock.DALMapperMockFactory.DALPurchaseOrderHeaderMapperMock); List <ApiVendorResponseModel> response = await service.All(); response.Should().HaveCount(1); mock.RepositoryMock.Verify(x => x.All(It.IsAny <int>(), It.IsAny <int>())); }