made backrefs aware of "post_update" and "viewonly" so it doesnt have to be explicitly propigated; also backrefs shouldnt fire off in a post_update situation.

3 files changed, 13 insertions, 9 deletions

diff --git a/lib/sqlalchemy/orm/dependency.py b/lib/sqlalchemy/orm/dependency.py
index 133d51b7f..5b95b4d7a 100644
--- a/lib/sqlalchemy/orm/dependency.py
+++ b/lib/sqlalchemy/orm/dependency.py
@@ -115,10 +115,11 @@ class DependencyProcessor(object):
 class OneToManyDP(DependencyProcessor):
     def register_dependencies(self, uowcommit):
         if self.post_update:
-            stub = MapperStub(self.parent, self.mapper, self.key)
-            uowcommit.register_dependency(self.mapper, stub)
-            uowcommit.register_dependency(self.parent, stub)
-            uowcommit.register_processor(stub, self, self.parent)
+            if not self.is_backref:
+                stub = MapperStub(self.parent, self.mapper, self.key)
+                uowcommit.register_dependency(self.mapper, stub)
+                uowcommit.register_dependency(self.parent, stub)
+                uowcommit.register_processor(stub, self, self.parent)
         else:
             uowcommit.register_dependency(self.parent, self.mapper)
             uowcommit.register_processor(self.parent, self, self.parent)
@@ -204,10 +205,11 @@ class OneToManyDP(DependencyProcessor):
 class ManyToOneDP(DependencyProcessor):
     def register_dependencies(self, uowcommit):
         if self.post_update:
-            stub = MapperStub(self.parent, self.mapper, self.key)
-            uowcommit.register_dependency(self.mapper, stub)
-            uowcommit.register_dependency(self.parent, stub)
-            uowcommit.register_processor(stub, self, self.parent)
+            if not self.is_backref:
+                stub = MapperStub(self.parent, self.mapper, self.key)
+                uowcommit.register_dependency(self.mapper, stub)
+                uowcommit.register_dependency(self.parent, stub)
+                uowcommit.register_processor(stub, self, self.parent)
         else:
             uowcommit.register_dependency(self.mapper, self.parent)
             uowcommit.register_processor(self.mapper, self, self.parent)
diff --git a/lib/sqlalchemy/orm/properties.py b/lib/sqlalchemy/orm/properties.py
index 959c7675e..af98c12cd 100644
--- a/lib/sqlalchemy/orm/properties.py
+++ b/lib/sqlalchemy/orm/properties.py
@@ -306,6 +306,8 @@ class BackRef(object):
             sj = self.kwargs.pop('secondaryjoin', None)
             # the backref property is set on the primary mapper
             parent = prop.parent.primary_mapper()
+            self.kwargs.setdefault('viewonly', prop.viewonly)
+            self.kwargs.setdefault('post_update', prop.post_update)
             relation = PropertyLoader(parent, prop.secondary, pj, sj, backref=prop.key, is_backref=True, **self.kwargs)
             mapper._compile_property(self.key, relation);
         elif not isinstance(mapper.props[self.key], PropertyLoader):
diff --git a/test/orm/cycles.py b/test/orm/cycles.py
index 5ec042648..7f7e1ada9 100644
--- a/test/orm/cycles.py
+++ b/test/orm/cycles.py
@@ -496,7 +496,7 @@ class OneToManyManyToOneTest(AssertMixin):
 
         Ball.mapper = mapper(Ball, ball)
         Person.mapper = mapper(Person, person, properties= dict(
-         balls = relation(Ball.mapper, primaryjoin=ball.c.person_id==person.c.id, foreignkey=ball.c.person_id, private=True, post_update=True),
+         balls = relation(Ball.mapper, primaryjoin=ball.c.person_id==person.c.id, foreignkey=ball.c.person_id, private=True, post_update=True, backref='person'),
          favorateBall = relation(Ball.mapper, primaryjoin=person.c.favorite_ball_id==ball.c.id, foreignkey=person.c.favorite_ball_id),
          )
         )