only flush if write was successful; if it throws when writing, make sure that...

only flush if write was successful; if it throws when writing, make sure that items in a transaction are aborted

StackExchange.Redis/Message.cs

@@ -614,9 +614,10 @@ internal void Fail(ConnectionFailureType failure, Exception innerException, stri
             resultProcessor?.ConnectionFail(this, failure, innerException, annotation);
         }
 
-        internal void SetException(Exception exception)
+        internal virtual void SetExceptionAndComplete(Exception exception, PhysicalBridge bridge)
         {
             resultBox?.SetException(exception);
+            bridge.CompleteSyncOrAsync(this);
         }
 
         internal bool TrySetResult<T>(T value) => resultBox is ResultBox<T> typed && typed.TrySetResult(value);

StackExchange.Redis/PhysicalBridge.cs

@@ -371,8 +371,7 @@ private void AbandonPendingBacklog(Exception ex)
                 if (next != null)
                 {
                     Multiplexer?.OnMessageFaulted(next, ex);
-                    next.SetException(ex);
-                    this.CompleteSyncOrAsync(next);
+                    next.SetExceptionAndComplete(ex, this);
                 }
             } while (next != null);
         }
@@ -603,9 +602,19 @@ internal WriteResult WriteMessageTakingWriteLock(PhysicalConnection physical, Me
                 {
                     result = WriteMessageToServerInsideWriteLock(physical, message);
                 }
-                result = physical.FlushSync();
+
+                if (result == WriteResult.Success)
+                {
+                    result = physical.FlushSync();
+                }
                 physical.SetIdle();
             }
+            catch (Exception ex)
+            {
+                var inner = new RedisConnectionException(ConnectionFailureType.InternalFailure, "Failed to write", ex);
+                message.SetExceptionAndComplete(inner, this);
+                result = WriteResult.WriteFailure;
+            }
             finally
             {
                 if (haveLock)

StackExchange.Redis/PhysicalConnection.cs

@@ -403,6 +403,7 @@ void add(string lk, string sk, string v)
                     if (next.Command == RedisCommand.QUIT && next.TrySetResult(true))
                     {
                         // fine, death of a socket is close enough
+                        bridge.CompleteSyncOrAsync(next);
                     }
                     else
                     {
@@ -412,9 +413,8 @@ void add(string lk, string sk, string v)
                             bridge.Trace("Failing: " + next);
                             bridge.Multiplexer?.OnMessageFaulted(next, ex, origin);
                         }
-                        next.SetException(ex);
+                        next.SetExceptionAndComplete(ex, bridge);
                     }
-                    bridge.CompleteSyncOrAsync(next);
                 }
             }
 
@@ -589,8 +589,7 @@ internal void OnBridgeHeartbeat()
                         {
                             var timeoutEx = ExceptionFactory.Timeout(includeDetail, $"Timeout awaiting response ({elapsed}ms elapsed, timeout is {timeout}ms)", msg, server);
                             bridge.Multiplexer?.OnMessageFaulted(msg, timeoutEx);
-                            msg.SetException(timeoutEx); // tell the message that it is doomed
-                            bridge.CompleteSyncOrAsync(msg); // prod it - kicks off async continuations etc
+                            msg.SetExceptionAndComplete(timeoutEx, bridge); // tell the message that it is doomed
                             bridge.Multiplexer.OnAsyncTimeout();
                         }
                         // note: it is important that we **do not** remove the message unless we're tearing down the socket; that

StackExchange.Redis/RedisTransaction.cs

@@ -198,6 +198,19 @@ public TransactionMessage(int db, CommandFlags flags, List<ConditionResult> cond
                 this.conditions = (conditions == null || conditions.Count == 0) ? Array.Empty<ConditionResult>(): conditions.ToArray();
             }
 
+            internal override void SetExceptionAndComplete(Exception exception, PhysicalBridge bridge)
+            {
+                var inner = InnerOperations;
+                if (inner != null)
+                {
+                    for(int i = 0; i < inner.Length;i++)
+                    {
+                        inner[i].Wrapped.SetExceptionAndComplete(exception, bridge);
+                    }
+                }
+                base.SetExceptionAndComplete(exception, bridge);
+            }
+
             public bool IsAborted => command != RedisCommand.EXEC;
 
             public override void AppendStormLog(StringBuilder sb)