public void RemoveCategoryTest()
        {
            IViewModelHelper viewModelHelper = new ViewModelHelperFake();
            MainViewModel    viewModel       = new MainViewModel();

            viewModel.ViewModelHelper = viewModelHelper;
            viewModel.RemoveCategoryCommand.Execute(null);
            Assert.AreEqual(4, viewModel.DataLayer.GetAllProductCategories().ToList().Count);
        }
        public void UpdateCategoryTest()
        {
            IViewModelHelper viewModelHelper = new ViewModelHelperFake();
            MainViewModel    viewModel       = new MainViewModel();

            viewModel.ViewModelHelper = viewModelHelper;
            viewModel.Name            = "Test";
            viewModel.ID = 1;
            viewModel.UpdateCategoryCommand.Execute(null);
            Assert.IsNull(viewModel.DataLayer.GetProductCategoryByName("Test"));
        }