From 4e4102f64d0b467649cb372460945a6a7f910884 Mon Sep 17 00:00:00 2001
From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Thu, 9 Jul 2009 01:45:44 +0000
Subject: [PATCH] - Fixed bug whereby session.is_modified() would raise an
 exception if any synonyms were in use.

---
 CHANGES                       |  3 +++
 lib/sqlalchemy/orm/session.py | 12 ++++++++++--
 test/orm/test_session.py      | 10 ++++++++++
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/CHANGES b/CHANGES
index cf2f8150d1..16b21f634a 100644
--- a/CHANGES
+++ b/CHANGES
@@ -31,6 +31,9 @@ CHANGES
       wouldn't be deserialized correctly when the whole object
       was serialized.  [ticket:1426]
 
+    - Fixed bug whereby session.is_modified() would raise an exception
+      if any synonyms were in use.
+      
     - Fixed Query being able to join() from individual columns of
       a joined-table subclass entity, i.e.
       query(SubClass.foo, SubcClass.bar).join(<anything>).
diff --git a/lib/sqlalchemy/orm/session.py b/lib/sqlalchemy/orm/session.py
index cbfb0c1d64..a658783c2c 100644
--- a/lib/sqlalchemy/orm/session.py
+++ b/lib/sqlalchemy/orm/session.py
@@ -1473,10 +1473,18 @@ class Session(object):
             state = attributes.instance_state(instance)
         except exc.NO_STATE:
             raise exc.UnmappedInstanceError(instance)
+        dict_ = state.dict
         for attr in state.manager.attributes:
-            if not include_collections and hasattr(attr.impl, 'get_collection'):
+            if \
+                (
+                    not include_collections and 
+                    hasattr(attr.impl, 'get_collection')
+                ) or not hasattr(attr.impl, 'get_history'):
                 continue
-            (added, unchanged, deleted) = attr.get_history(instance, passive=passive)
+                
+            (added, unchanged, deleted) = \
+                    attr.impl.get_history(state, dict_, passive=passive)
+                                            
             if added or deleted:
                 return True
         return False
diff --git a/test/orm/test_session.py b/test/orm/test_session.py
index 3020d66e9d..a94b4e7df7 100644
--- a/test/orm/test_session.py
+++ b/test/orm/test_session.py
@@ -747,6 +747,16 @@ class SessionTest(_fixtures.FixtureTest):
         assert s.is_modified(user)
         assert not s.is_modified(user, include_collections=False)
 
+    @testing.resolve_artifact_names
+    def test_is_modified_syn(self):
+        s = sessionmaker()()
+
+        mapper(User, users, properties={'uname':sa.orm.synonym('name')})
+        u = User(uname='fred')
+        assert s.is_modified(u)
+        s.add(u)
+        s.commit()
+        assert not s.is_modified(u)
 
     @testing.resolve_artifact_names
     def test_weak_ref(self):
-- 
2.47.2