Can use slighly less coarse-grained locking here

michaelklishin · michaelklishin · commit 9c2152c7a20e · 2014-04-16T13:12:35.000+04:00
evt is a local variable and thus cannot possibly be shared
diff --git a/projects/client/RabbitMQ.Client/src/client/messagepatterns/Subscription.cs b/projects/client/RabbitMQ.Client/src/client/messagepatterns/Subscription.cs
@@ -235,12 +235,12 @@ public void Nack(BasicDeliverEventArgs evt,
                          bool multiple,
                          bool requeue)
         {
+            if (evt == null) {
+                return;
+            }
+
             lock(m_eventLock)
             {
-                if (evt == null) {
-                    return;
-                }
-
                 if (!m_noAck) {
                     m_model.BasicNack(evt.DeliveryTag, multiple, requeue);
                 }

Original file line number	Diff line number	Diff line change
`@@ -235,12 +235,12 @@ public void Nack(BasicDeliverEventArgs evt,`
`235`	`235`	`bool multiple,`
`236`	`236`	`bool requeue)`
`237`	`237`	`{`
	`238`	`+ if (evt == null) {`
	`239`	`+ return;`
	`240`	`+ }`
	`241`	`+`
`238`	`242`	`lock(m_eventLock)`
`239`	`243`	`{`
`240`		`- if (evt == null) {`
`241`		`- return;`
`242`		`- }`
`243`		`-`
`244`	`244`	`if (!m_noAck) {`
`245`	`245`	`m_model.BasicNack(evt.DeliveryTag, multiple, requeue);`
`246`	`246`	`}`