add debug for nudges

OpenRA.Game/Traits/Activities/Move.cs

@@ -182,6 +182,9 @@ namespace OpenRA.Traits.Activities
 			var blocker = self.World.WorldActor.Trait<UnitInfluence>().GetUnitsAt(nextCell).FirstOrDefault();
 			if (blocker == null) return;
 
+			Log.Write("debug", "NudgeBlocker #{0} nudges #{1} at {2} from {3}",
+				self.ActorID, blocker.ActorID, nextCell, self.Location);
+
 			var nudge = blocker.TraitOrDefault<INudge>();
 			if (nudge != null)
 				nudge.OnNudge(blocker, self);

OpenRA.Game/Traits/Mobile.cs

@@ -354,7 +354,13 @@ namespace OpenRA.Traits
 							line.SetTargetSilently(self, Target.FromCell(moveTo.Value), Color.Green);
 					});
 				self.QueueActivity(new Move(moveTo.Value, 0));
+
+				Log.Write("debug", "OnNudge #{0} from {1} to {2}",
+					self.ActorID, self.Location, moveTo.Value);
 			}
+			else
+				Log.Write("debug", "OnNudge #{0} refuses at {1}",
+					self.ActorID, self.Location);
 		}
 	}
 }