Merge pull request #351 from andrewschultz/dangling-connection-exception

check for null ports in diagonal/bent (correct source this time)

MapStatistics.cs

@@ -206,8 +206,9 @@ public static int DiagonalConnections(int checkval)
         var port1 = (Room.CompassPort)p.VertexList[0].Port;
         var port2 = (Room.CompassPort)p.VertexList[1].Port;
 
-        var firstRoomConnectionDir = (int)port1?.CompassPoint;
-        var secondRoomConnectionDir = (int)port2?.CompassPoint;
+        var firstRoomConnectionDir = (port1 == null) ? 0 : (int)port1?.CompassPoint;
+        var secondRoomConnectionDir = (port2 == null) ? 0 : (int)port2?.CompassPoint;
+
         var diags = 0;
 
         if ((firstRoomConnectionDir % 4 == 2) && (p.VertexList[0].Connection.StartText == ""))
@@ -227,6 +228,9 @@ public static int BentConnections(bool ignoreAnnos)
         var port1 = (Room.CompassPort)p.VertexList[0].Port;
         var port2 = (Room.CompassPort)p.VertexList[1].Port;
 
+        if (port1 == null || port2 == null)
+          return false;
+
         var firstRoomConnectionDir = port1.CompassPoint;
         var secondRoomConnectionDir = port2.CompassPoint;