using System;

using System.Threading;

using System.Threading.Tasks;

public class Program

{

    public static async Task Main()

    {

        var asyncLock = new ReentrantAsyncLock.ReentrantAsyncLock();

        await using (await asyncLock.LockAsync(CancellationToken.None))

        {

            var contextBefore = SynchronizationContext.Current;

            await AsyncTaskMethod();

            var contextAfter = SynchronizationContext.Current;

            Console.WriteLine("AsyncTaskMethod is " + (contextBefore == contextAfter ? "okay" : "not okay"));

        }

        await using (await asyncLock.LockAsync(CancellationToken.None))

        {

            var contextBefore = SynchronizationContext.Current;

            await TaskMethod();

            var contextAfter = SynchronizationContext.Current;

            Console.WriteLine("TaskMethod is " + (contextBefore == contextAfter ? "okay" : "not okay"));

        }

    }

    static Task TaskMethod(){

        SynchronizationContext.SetSynchronizationContext(null);

        return Task.Delay(1);

    }

​

    static async Task AsyncTaskMethod(){

        SynchronizationContext.SetSynchronizationContext(null);

        await Task.Delay(1).ConfigureAwait(false);

    }

}