set the exception on a single message if ComputeResult *itself* fails

StackExchange.Redis/StackExchange/Redis/Message.cs

@@ -582,7 +582,15 @@ internal void Cancel(Exception ex = null)
         // true if ready to be completed (i.e. false if re-issued to another server)
         internal bool ComputeResult(PhysicalConnection connection, RawResult result)
         {
-            return resultProcessor == null || resultProcessor.SetResult(connection, this, result);
+            try
+            {
+                return resultProcessor == null || resultProcessor.SetResult(connection, this, result);
+            }
+            catch (Exception ex)
+            {
+                resultBox?.SetException(ex);
+                return true; // we still want to pulse/complete
+            }
         }
 
         internal void Fail(ConnectionFailureType failure, Exception innerException)

StackExchange.Redis/StackExchange/Redis/MessageQueue.cs

-using System.Collections.Generic;
-using System.Text;
-
-namespace StackExchange.Redis
-{
-    internal sealed partial class MessageQueue
-    {
-        private readonly Queue<Message>
-            regular = new Queue<Message>(),
-            high = new Queue<Message>();
-
-        public object SyncLock => regular;
-
-        public Message Dequeue()
-        {
-            lock (regular)
-            {
-                if (high.Count != 0)
-                {
-                    return high.Dequeue();
-                }
-                if (regular.Count != 0)
-                {
-                    return regular.Dequeue();
-                }
-            }
-            return null;
-        }
-
-        /// <summary>
-        /// Checks both high-pri and regular queues to see if the next item is a PING, and if so: dequeues it and returns it
-        /// </summary>
-        /// <param name="queueLength">The current queue count.</param>
-        public Message DequeueUnsentPing(out int queueLength)
-        {
-            lock (regular)
-            {
-                Message peeked;
-                queueLength = high.Count + regular.Count;
-                //In a disconnect scenario, we don't want to complete the Ping message twice,
-                //dequeue it now so it wont get dequeued in AbortUnsent (if we're going down that code path)
-                if (high.Count != 0 && (peeked = high.Peek()).Command == RedisCommand.PING)
-                {
-                    queueLength--;
-                    return high.Dequeue();
-                }
-                if (regular.Count != 0 && (peeked = regular.Peek()).Command == RedisCommand.PING)
-                {
-                    queueLength--;
-                    return regular.Dequeue();
-                }
-            }
-            return null;
-        }
-
-        public bool Push(Message message)
-        {
-            lock (regular)
-            {
-                (message.IsHighPriority ? high : regular).Enqueue(message);
-                return high.Count + regular.Count == 1;
-            }
-        }
-
-        internal bool Any()
-        {
-            lock (regular)
-            {
-                return high.Count != 0 || regular.Count != 0;
-            }
-        }
-
-        internal int Count()
-        {
-            lock (regular)
-            {
-                return high.Count + regular.Count;
-            }
-        }
-
-        internal Message[] DequeueAll()
-        {
-            lock (regular)
-            {
-                int count = high.Count + regular.Count;
-                if (count == 0) return Message.EmptyArray;
-
-                var arr = new Message[count];
-                high.CopyTo(arr, 0);
-                regular.CopyTo(arr, high.Count);
-                high.Clear();
-                regular.Clear();
-                return arr;
-            }
-        }
-
-        internal void GetStormLog(StringBuilder sb)
-        {
-            lock(regular)
-            {
-                int total = 0;
-                if (high.Count == 0 && regular.Count == 0) return;
-                sb.Append("Unsent: ").Append(high.Count + regular.Count).AppendLine();
-                foreach (var item in high)
-                {
-                    if (++total >= 500) break;
-                    item.AppendStormLog(sb);
-                    sb.AppendLine();
-                }
-                foreach (var item in regular)
-                {
-                    if (++total >= 500) break;
-
-                    item.AppendStormLog(sb);
-                    sb.AppendLine();
-                }
-            }
-        }
-    }
-}