From 4b1ca23027493d8d1b7ea48d4585699b0d126d16 Mon Sep 17 00:00:00 2001
From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Sun, 18 Aug 2013 15:34:23 -0400
Subject: [PATCH] Fixed a potential issue in an ordered sequence implementation
 used by the ORM to iterate mapper hierarchies; under the Jython interpreter
 this implementation wasn't ordered, even though cPython and Pypy maintained
 ordering.  Also in 0.8.3. [ticket:2794]

Conflicts:
	doc/build/changelog/changelog_09.rst
	lib/sqlalchemy/util/_collections.py
---
 doc/build/changelog/changelog_08.rst |  9 +++++++++
 lib/sqlalchemy/orm/util.py           |  1 +
 lib/sqlalchemy/util/_collections.py  | 17 +++++++++++++----
 3 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/doc/build/changelog/changelog_08.rst b/doc/build/changelog/changelog_08.rst
index bbd2741c80..d67c088eb1 100644
--- a/doc/build/changelog/changelog_08.rst
+++ b/doc/build/changelog/changelog_08.rst
@@ -6,6 +6,15 @@
 .. changelog::
     :version: 0.8.3
 
+    .. change::
+        :tags: bug, orm
+        :tickets: 2794
+
+        Fixed a potential issue in an ordered sequence implementation used
+        by the ORM to iterate mapper hierarchies; under the Jython interpreter
+        this implementation wasn't ordered, even though cPython and Pypy
+        maintained ordering.
+
     .. change::
         :tags: bug, sql
         :tickets: 2801
diff --git a/lib/sqlalchemy/orm/util.py b/lib/sqlalchemy/orm/util.py
index e2b3ddd01c..99349c0197 100644
--- a/lib/sqlalchemy/orm/util.py
+++ b/lib/sqlalchemy/orm/util.py
@@ -1292,3 +1292,4 @@ def randomize_unitofwork():
     from sqlalchemy.testing.util import RandomSet
     topological.set = unitofwork.set = session.set = mapper.set = \
             dependency.set = RandomSet
+
diff --git a/lib/sqlalchemy/util/_collections.py b/lib/sqlalchemy/util/_collections.py
index 8e61275e75..4da13b3fe0 100644
--- a/lib/sqlalchemy/util/_collections.py
+++ b/lib/sqlalchemy/util/_collections.py
@@ -618,18 +618,27 @@ class IdentitySet(object):
 
 class WeakSequence(object):
     def __init__(self, elements):
-        self._storage = weakref.WeakValueDictionary(
-            (idx, element) for idx, element in enumerate(elements)
-        )
+        self._storage = [
+            weakref.ref(element) for element in elements
+        ]
+
+    def _remove(self, ref):
+        self._storage.remove(ref)
 
     def __iter__(self):
+<<<<<<< HEAD
         return self._storage.itervalues()
+=======
+        return (obj for obj in (ref() for ref in self._storage) if obj is not None)
+>>>>>>> 676876f... Fixed a potential issue in an ordered sequence implementation used
 
     def __getitem__(self, index):
         try:
-            return self._storage[index]
+            obj = self._storage[index]
         except KeyError:
             raise IndexError("Index %s out of range" % index)
+        else:
+            return obj()
 
 
 class OrderedIdentitySet(IdentitySet):
-- 
2.47.3