Give a clone of the map to the player

tron/game.py

@@ -111,7 +111,7 @@ class Game:
 
     def map(self):
         """
-        Returns the current map, the last map in the history.
+        Returns a clone of the current map, the last map in the history.
         """
         return self.history[-1].map.clone()
 
@@ -134,7 +134,7 @@ class Game:
 
         # Play next move
         for id, pp in enumerate(self.pps):
-            (pp.position, pp.player.direction) = pp.player.next_position_and_direction(pp.position, id + 1, self.history[-1].map)
+            (pp.position, pp.player.direction) = pp.player.next_position_and_direction(pp.position, id + 1, self.map())
 
         # Update history with newly played move
         self.history[-1].player_one_direction = self.pps[0].player.direction