- starting to groom the branch for its inclusion

- one-to-many relationships now maintain a list of positive
parent-child associations within the flush, preventing
previous parents marked as deleted from cascading a
delete or NULL foreign key set on those child objects,
despite the end-user not removing the child from the old
association. [ticket:1764]
- re-established Preprocess as unique on their arguments,
as they were definitely duped in inheritance scenarios
- added a "memo" feature to UOWTransaction which represents the usual
pattern of using the .attributes collection
- added the test case from [ticket:1081] into perf/

1 files changed, 1 insertions, 2 deletions

diff --git a/lib/sqlalchemy/orm/sync.py b/lib/sqlalchemy/orm/sync.py
index b9ddbb6e7..184ae8c84 100644
--- a/lib/sqlalchemy/orm/sync.py
+++ b/lib/sqlalchemy/orm/sync.py
@@ -75,8 +75,7 @@ def source_modified(uowcommit, source, source_mapper, synchronize_pairs):
         except exc.UnmappedColumnError:
             _raise_col_to_prop(False, source_mapper, l, None, r)
         history = uowcommit.get_attribute_history(source, prop.key, passive=True)
-        if len(history.deleted):
-            return True
+        return bool(history.deleted)
     else:
         return False