public void DeleteShouldWork()
        {
            var state = GetCurrentPrivateRecipeSystemState();
            var originalCount = state.Count;
            var sut = new PrivateRecipeRepository(state);
            var idToDelete = state[1].Id;

            sut.Delete(idToDelete);
            var results = sut.GetAll();
            results.Count.ShouldEqual(originalCount - 1);

            var recipe = sut.GetById(idToDelete);
            recipe.ShouldBeNull();
        }