Maxing sure continuations are consistently disposed because they tend to create timer based cancellation token sources and linked tokens

Author: danielmarbach

projects/RabbitMQ.Client/Impl/AsyncRpcContinuations.cs

@@ -51,7 +51,7 @@ internal abstract class AsyncRpcContinuation<T> : IRpcContinuation
 
         private bool _disposedValue;
 
-        public AsyncRpcContinuation(TimeSpan continuationTimeout, CancellationToken cancellationToken)
+        protected AsyncRpcContinuation(TimeSpan continuationTimeout, CancellationToken cancellationToken)
         {
             /*
              * Note: we can't use an ObjectPool for these because the netstandard2.0

projects/RabbitMQ.Client/Impl/Channel.PublisherConfirms.cs

@@ -131,38 +131,27 @@ private async Task MaybeConfirmSelect(CancellationToken cancellationToken)
             if (_publisherConfirmationsEnabled)
             {
                 // NOTE: _rpcSemaphore is held
-                bool enqueued = false;
-                var k = new ConfirmSelectAsyncRpcContinuation(ContinuationTimeout, cancellationToken);
+                using var k = new ConfirmSelectAsyncRpcContinuation(ContinuationTimeout, cancellationToken);
 
-                try
+                if (_nextPublishSeqNo == 0UL)
                 {
-                    if (_nextPublishSeqNo == 0UL)
+                    if (_publisherConfirmationTrackingEnabled)
                     {
-                        if (_publisherConfirmationTrackingEnabled)
-                        {
-                            _confirmsTaskCompletionSources.Clear();
-                        }
-                        _nextPublishSeqNo = 1;
+                        _confirmsTaskCompletionSources.Clear();
                     }
+                    _nextPublishSeqNo = 1;
+                }
 
-                    enqueued = Enqueue(k);
+                Enqueue(k);
 
-                    var method = new ConfirmSelect(false);
-                    await ModelSendAsync(in method, k.CancellationToken)
-                        .ConfigureAwait(false);
+                var method = new ConfirmSelect(false);
+                await ModelSendAsync(in method, k.CancellationToken)
+                    .ConfigureAwait(false);
 
-                    bool result = await k;
-                    Debug.Assert(result);
+                bool result = await k;
+                Debug.Assert(result);
 
-                    return;
-                }
-                finally
-                {
-                    if (false == enqueued)
-                    {
-                        k.Dispose();
-                    }
-                }
+                return;
             }
         }