Merge pull request #102 from pharo-nosql/correct_pool-return-for-broken

Add a flag to exception handling to prevent returning a broken connec…

mc/Mongo-Client.package/MongoPool.class/instance/mongoDo..st

@@ -2,22 +2,26 @@ accessing
 mongoDo: aBlockClosure
 	"Evaluate the BlockClosure with a Mongo instance. See #next.
 	
-	For error handling, the specification states that the client MUST clear its connection pool for the server: if one socket is bad, it is likely that all are.
+	For error handling, the specification states that the client MUST clear its connection pool 
+	for the server: if one socket is bad, it is likely that all are.
 
 	Source: https://github.com/mongodb/specifications/blob/573b1f58a129056d651781ad99317b6c656e050e/source/server-discovery-and-monitoring/server-discovery-and-monitoring-summary.rst#id9
 	"
 
-	| mongo result |
-	[	mongo := self next.
-		result := [ aBlockClosure value: mongo]
-			ensure: [ 
-				"Use ensurce block here because the block above could have a non local 
-				return which would skip returning the connection. In the error case the 
-				pool will get resetted so this should not have any impact"
-				self return: mongo ].
-		^ result ]
+	| mongo failed |
+	failed := false.
+	mongo := self next.
+	^ [	
+		[ aBlockClosure value: mongo ]
 			on: NetworkError, MongoWireProtocolError
 			do: [ :error |
+				failed := true.
 				self ensureCloseMongo: mongo.
 				self resetAll.
-				error pass ]
+				error pass ] ]
+		ensure: [ 
+			"Use ensurce block here because aBlockClosure could have a non local 
+			return which would skip returning the connection. So we only return 
+			if the prior exception handler did not mark this as failed"
+			failed ifFalse: [ 
+				self return: mongo ] ]