[Python-checkins] r73401 - in python/trunk/Lib: collections.py test/test_collections.py

Fri Jun 12 23:52:14 CEST 2009

Author: alexandre.vassalotti
Date: Fri Jun 12 23:52:14 2009
New Revision: 73401
Log:
Make pickling of OrderedDict instances more efficient.
Modified:
 python/trunk/Lib/collections.py
 python/trunk/Lib/test/test_collections.py
Modified: python/trunk/Lib/collections.py
==============================================================================

--- python/trunk/Lib/collections.py	(original)
+++ python/trunk/Lib/collections.py	Fri Jun 12 23:52:14 2009
@@ -99,14 +99,16 @@
 
 def __reduce__(self):
 'Return state information for pickling'
- items = [[k, self[k]] for k in self]
+ dictitems = self.iteritems()
 tmp = self.__map, self.__root
 del self.__map, self.__root
 inst_dict = vars(self).copy()
 self.__map, self.__root = tmp
- if inst_dict:
- return (self.__class__, (items,), inst_dict)
- return self.__class__, (items,)
+ # Set the state item to None when the dictionary is empty. This saves
+ # about 2 opcodes when the object is pickled.
+ if not inst_dict:
+ inst_dict = None
+ return (self.__class__, (), inst_dict, None, dictitems)
 
 setdefault = MutableMapping.setdefault
 update = MutableMapping.update
Modified: python/trunk/Lib/test/test_collections.py
==============================================================================
--- python/trunk/Lib/test/test_collections.py	(original)
+++ python/trunk/Lib/test/test_collections.py	Fri Jun 12 23:52:14 2009
@@ -795,9 +795,9 @@
 # do not save instance dictionary if not needed
 pairs = [('c', 1), ('b', 2), ('a', 3), ('d', 4), ('e', 5), ('f', 6)]
 od = OrderedDict(pairs)
- self.assertEqual(len(od.__reduce__()), 2)
 od.x = 10
- self.assertEqual(len(od.__reduce__()), 3)
+ self.assertGreaterEqual(len(od.__reduce__()), 2)
+ self.assertLessEqual(len(od.__reduce__()), 5)
 
 def test_repr(self):
 od = OrderedDict([('c', 1), ('b', 2), ('a', 3), ('d', 4), ('e', 5), ('f', 6)])
