gistfile1.cs

public static class DbAsyncEnumerableExtensions
{
    public static IAsyncEnumerable<T> AsAsyncEnumerable<T>(this IDbAsyncEnumerable<T> source)
    {
        Check.NotNull(source, "source");
        return new DbAsyncEnumerableAdapter<T>(source);
    }

    private struct DbAsyncEnumerableAdapter<T> : IAsyncEnumerable<T>
    {
        private readonly IDbAsyncEnumerable<T> source;

        public DbAsyncEnumerableAdapter(IDbAsyncEnumerable<T> source)
        {
            this.source = source;
        }

        public IAsyncEnumerator<T> GetEnumerator()
        {
            return new DbAsyncEnumeratorAdapter<T>(source.GetAsyncEnumerator());
        }
    }

    private struct DbAsyncEnumeratorAdapter<T> : IAsyncEnumerator<T>
    {
        private readonly IDbAsyncEnumerator<T> source;

        public DbAsyncEnumeratorAdapter(IDbAsyncEnumerator<T> source)
        {
            this.source = source;
        }

        public T Current
        {
            get { return source.Current; }
        }

        public Task<bool> MoveNext(CancellationToken cancellationToken)
        {
            return source.MoveNextAsync(cancellationToken);
        }

        public void Dispose()
        {
            source.Dispose();
        }
    }
}