CommandTest.cs

// Fire Command
 [Test(Description = "Added product shows up in repository with correct savestate")]
 public void ExecutingCreateProductCommand_WithNewProduct_ShowsUpInRepository()
 {
     // Given the user wants to create a new product on the Create Product View
     var product = new Product("4242", "desc", ProductType.Assortment, "201001", "123", _dummyArticles, null,
                               1);

     // When the user clicks the New button a CreateProductCommand is fired on the ViewModel
     var viewModel = new ProductViewModel(product);
     ICommand command = viewModel.CreateProductCommand;
     command.Execute(null);

     // Then the created product shows up in the Product repository and has savestate set to SaveState.New
     Assert.True(Registry.Instance.ProductRepository.LoadedModels.Contains(product));
     Assert.That(product.State,Is.EqualTo(SaveState.New));
 }