public void FindIDExisting()
        {
            // Arrange
            ShippingDocumentService service = new ShippingDocumentService();

            // Act
            var doc  = service.Create();
            var find = service.Find(doc.ID);

            // Assert
            Assert.AreEqual(find, doc);
        }
        public void FindIDNotExisting()
        {
            // Arrange
            Mock <IShippingDocumentRepository> repositoryMock = new Mock <IShippingDocumentRepository>();
            ShippingDocumentService            service        = new ShippingDocumentService(repositoryMock.Object);

            // Act
            var doc = service.Find(0);

            // Assert
            Assert.IsNull(doc);
        }