Fix cursor cloning issue with deepcopy and regex mongodb#179

Author: rozza

pymongo/cursor.py

@@ -841,22 +841,33 @@ def __deepcopy__(self, memo):
  return self.__clone(deepcopy=True)
 
  def __deepcopy(self, x, memo=None):
- """Deepcopy helper for the data dictionary.
+ """Deepcopy helper for the data dictionary or list.
 
  Regular expressions cannot be deep copied but as they are immutable we
  don't have to copy them when cloning.
  """
- y = {}
+ if not hasattr(x, 'items'):
+ y, is_list, iterator = [], True, enumerate(x)
+ else:
+ y, is_list, iterator = {}, False, x.iteritems()
+
  if memo is None:
  memo = {}
  val_id = id(x)
  if val_id in memo:
  return memo.get(val_id)
  memo[val_id] = y
- for key, value in x.iteritems():
- if isinstance(value, dict) and not isinstance(value, SON):
+
+ for key, value in iterator:
+ if isinstance(value, (dict, list)) and not isinstance(value, SON):
  value = self.__deepcopy(value, memo)
  elif not isinstance(value, RE_TYPE):
  value = copy.deepcopy(value, memo)
- y[copy.deepcopy(key, memo)] = value
+
+ if is_list:
+ y.append(value)
+ else:
+ if not isinstance(key, RE_TYPE):
+ key = copy.deepcopy(key, memo)
+ y[key] = value
  return y

test/test_cursor.py

@@ -529,6 +529,16 @@ class MyClass(dict):
  self.assertTrue(isinstance(cursor2._Cursor__hint, SON))
  self.assertEqual(cursor._Cursor__hint, cursor2._Cursor__hint)
 
+ def test_deepcopy_cursor_littered_with_regexes(self):
+
+ cursor = self.db.test.find({"x": re.compile("^hmmm.*"),
+ "y": [re.compile("^hmm.*")],
+ "z": {"a": [re.compile("^hm.*")]},
+ re.compile("^key.*"): {"a": [re.compile("^hm.*")]}})
+
+ cursor2 = copy.deepcopy(cursor)
+ self.assertEqual(cursor._Cursor__spec, cursor2._Cursor__spec)
+
  def test_add_remove_option(self):
  cursor = self.db.test.find()
  self.assertEqual(0, cursor._Cursor__query_options())