public void AddShipper_GivenANewShipper_AddsToDatabase() { // arrange Shipper shipper = new Shipper() { ID = 3, Name = "DHL" }; Mock <IShipperRepository> mockShipperRepo = new Mock <IShipperRepository>(); ShippingService sut = new ShippingService(mockShipperRepo.Object, null, null, null); // act sut.AddShipper(shipper); // assert mockShipperRepo.Verify( r => r.AddShipper(It.Is <Shipper>(s => s.ID == 3 && s.Name.Equals("DHL"))), Times.Once()); }