- Fixed a bug involving contains_eager(), which would apply itself

to a secondary (i.e. lazy) load in a particular rare case,
producing cartesian products.   improved the targeting
of query.options() on secondary loads overall [ticket:1461].

3 files changed, 24 insertions, 7 deletions

diff --git a/lib/sqlalchemy/orm/__init__.py b/lib/sqlalchemy/orm/__init__.py
index 7b840a50d..6af8dde9f 100644
--- a/lib/sqlalchemy/orm/__init__.py
+++ b/lib/sqlalchemy/orm/__init__.py
@@ -934,7 +934,7 @@ def contains_eager(*keys, **kwargs):
     if kwargs:
         raise exceptions.ArgumentError("Invalid kwargs for contains_eager: %r" % kwargs.keys())
 
-    return (strategies.EagerLazyOption(keys, lazy=False), strategies.LoadEagerFromAliasOption(keys, alias=alias))
+    return (strategies.EagerLazyOption(keys, lazy=False, _only_on_lead=True), strategies.LoadEagerFromAliasOption(keys, alias=alias))
 
 @sa_util.accepts_a_list_as_starargs(list_deprecation='pending')
 def defer(*keys):
diff --git a/lib/sqlalchemy/orm/interfaces.py b/lib/sqlalchemy/orm/interfaces.py
index 0ac771305..9a9ebfcab 100644
--- a/lib/sqlalchemy/orm/interfaces.py
+++ b/lib/sqlalchemy/orm/interfaces.py
@@ -682,13 +682,14 @@ class PropertyOption(MapperOption):
             searchfor = mapper
         else:
             searchfor = _class_to_mapper(mapper).base_mapper
-
+        
         for ent in query._mapper_entities:
             if ent.path_entity is searchfor:
                 return ent
         else:
             if raiseerr:
-                raise sa_exc.ArgumentError("Can't find entity %s in Query.  Current list: %r" % (searchfor, [str(m.path_entity) for m in query._entities]))
+                raise sa_exc.ArgumentError("Can't find entity %s in Query.  Current list: %r" 
+                    % (searchfor, [str(m.path_entity) for m in query._entities]))
             else:
                 return None
 
@@ -718,8 +719,10 @@ class PropertyOption(MapperOption):
         entity = None
         l = []
 
+        # _current_path implies we're in a secondary load
+        # with an existing path
         current_path = list(query._current_path)
-
+            
         if self.mapper:
             entity = self.__find_entity(query, self.mapper, raiseerr)
             mapper = entity.mapper
@@ -752,7 +755,7 @@ class PropertyOption(MapperOption):
                 if current_path and key == current_path[1]:
                     current_path = current_path[2:]
                     continue
-
+                    
                 if prop is None:
                     return []
 
@@ -764,7 +767,12 @@ class PropertyOption(MapperOption):
                     path_element = mapper = getattr(prop, 'mapper', None)
                 if path_element:
                     path_element = path_element.base_mapper
-
+        
+        # if current_path tokens remain, then
+        # we didn't have an exact path match.
+        if current_path:
+            return []
+            
         return l
 
 class AttributeExtension(object):
diff --git a/lib/sqlalchemy/orm/strategies.py b/lib/sqlalchemy/orm/strategies.py
index 20cbb8f4d..ebb576a71 100644
--- a/lib/sqlalchemy/orm/strategies.py
+++ b/lib/sqlalchemy/orm/strategies.py
@@ -776,11 +776,16 @@ class EagerLoader(AbstractRelationLoader):
 log.class_logger(EagerLoader)
 
 class EagerLazyOption(StrategizedOption):
-    def __init__(self, key, lazy=True, chained=False, mapper=None):
+    def __init__(self, key, lazy=True, chained=False, mapper=None, _only_on_lead=False):
         super(EagerLazyOption, self).__init__(key, mapper)
         self.lazy = lazy
         self.chained = chained
+        self._only_on_lead = _only_on_lead
         
+    def process_query_conditionally(self, query):
+        if not self._only_on_lead:
+            StrategizedOption.process_query_conditionally(self, query)
+            
     def is_chained(self):
         return not self.lazy and self.chained
         
@@ -800,6 +805,10 @@ class LoadEagerFromAliasOption(PropertyOption):
                 m, alias, is_aliased_class = mapperutil._entity_info(alias)
         self.alias = alias
 
+    def process_query_conditionally(self, query):
+        # dont run this option on a secondary load
+        pass
+        
     def process_query_property(self, query, paths):
         if self.alias:
             if isinstance(self.alias, basestring):