ItemNotNullAttribute has problems?

Hi,

I'd like to comfirm that ItemNotNullAttrbute still has problems of null-cheking.

https://youtrack.jetbrains.com/issue/RSRP-466093

https://youtrack.jetbrains.com/issue/RSRP-462951

If so, I have an idea of substitution for ItemNotNullAttribute.

To use the following wrapper class instead of List<T> class.

public class ItemNotNullList<T> : IList<T>, ICollection<T>, IEnumerable<T>, IEnumerable, IList, ICollection, IReadOnlyList<T>, IReadOnlyCollection<T>
{
	[NotNull]
	private readonly List<T> list = new List<T>();

	[NotNull]
	public T this[int i]
	{
		get
		{
			System.Diagnostics.Debug.Assert(list[i] != null);
			return list[i];
		}
		set
		{
			list[i] = value;
		}
	}

	public void Add([NotNull]T item)
	{
		list.Add(item);
	}

        ...
}

It seems to work well.