public void ClearShouldUpdateLastModifiedTime()
        {
            var sut = new PrivateRecipe(_author, _title);
            var recipeItem1 = new RecipeItem(_itemDescription, sut);
            var recipeItem2 = new RecipeItem(_itemDescription, sut);
            sut.Add(recipeItem1);
            sut.Add(recipeItem2);
            var oldTime = sut.TimeLastModified;
            Thread.Sleep(100);

            sut.Clear();
            var newTime = sut.TimeLastModified;

            newTime.ShouldNotEqual(oldTime);
        }
        public void ClearShouldRemoveAllItems()
        {
            var sut = new PrivateRecipe(_author, _title);
            var recipeItem1 = new RecipeItem(_itemDescription, sut);
            var recipeItem2 = new RecipeItem(_itemDescription, sut);
            sut.Add(recipeItem1);
            sut.Add(recipeItem2);

            sut.Clear();

            sut.Items.Count.ShouldEqual(0);
        }