BUG: Ineligible autocomplete entries (generic extension methods with constraints)

JeffMercado

I have some extensions defined to help with chaining expressions with common interfaces and operations.

public static class ChainableExtensions
{
    public static T With<T>(this T source, Action<T> action)
    {
        action(source);
        return source;
    }
    public static TResult Let<T, TResult>(this T source, Func<T, TResult> func)
    {
        return func(source);
    }

    #region IDictionary<TKey, TValue> extensions
    public static TDictionary AddChained<TKey, TValue, TDictionary>(this TDictionary dict, TKey key, TValue value) where TDictionary : IDictionary<TKey, TValue>
    {
        dict.Add(key, value);
        return dict;
    }
    ...
    #endregion

    #region IList<T> extensions
    public static TList InsertChained<T, TList>(this TList list, int index, T item) where TList : IList<T>
    {
        list.Insert(index, item);
        return list;
    }
    ...
    #endregion

    #region ISet<T> extensions
    public static TSet UnionWithChained<T, TSet>(this TSet set, IEnumerable<T> other) where TSet : ISet<T>
    {
        set.UnionWith(other);
        return set;
    }
    ...
    #endregion

    #region ICollection<T> extensions
    public static TCollection AddChained<T, TCollection>(this TCollection coll, T item) where TCollection : ICollection<T>
    {
        coll.Add(item);
        return coll;
    }
    ...
    #endregion
}

Autocomplete doesn't seem to take the constraints into account. All of the above methods are showing as options in autocomplete, even for types that do not satisfy the constraint. I feel like this should be fixed.

LinqPad Beta 7.1.4
.Net Runtime 6.0.1

JoeAlbahari

LINQPad uses Roslyn to filter the autocompletion lists, which has an open issue with type constraints:
https://github.com/dotnet/roslyn/issues/39689