Improve clear() method. Keeps key/value refcnts >= 1 until final dict.clear() so that decrefs to zero won't trigger arbitrary code . Also runs a bit faster.

2010-04-03 03:14:28 +00:00 · 2010-04-03 03:14:28 +00:00 · 6b96ecb0ab
parent 93232660bb
commit 6b96ecb0ab
1 changed files with 8 additions and 2 deletions
--- a/Lib/collections.py
+++ b/Lib/collections.py
@ -107,8 +107,14 @@ class OrderedDict(dict, MutableMapping):

    def clear(self):
        'od.clear() -> None.  Remove all items from od.'
-        for k in dict.keys(self):
-            del self[k]
+        try:
+            for node in self.__map.itervalues():
+                del node[:]
+            self.__root[:] = [self.__root, self.__root, None]
+            self.__map.clear()
+        except AttributeError:
+            pass
+        dict.clear(self)

    setdefault = MutableMapping.setdefault
    update = MutableMapping.update