- rework PropComparator.adapted() to be PropComparator.adapt_to_entity(),

passes in AliasedInsp and allows more flexibility.
- rework the AliasedClass/AliasedInsp relationship so that AliasedInsp has
all state and functionality.  AliasedClass is just a facade.
[ticket:2756]

1 files changed, 15 insertions, 6 deletions

diff --git a/lib/sqlalchemy/orm/interfaces.py b/lib/sqlalchemy/orm/interfaces.py
index 396f234c4..150277be2 100644
--- a/lib/sqlalchemy/orm/interfaces.py
+++ b/lib/sqlalchemy/orm/interfaces.py
@@ -381,21 +381,30 @@ class PropComparator(operators.ColumnOperators):
 
     """
 
-    def __init__(self, prop, parentmapper, adapter=None):
+    def __init__(self, prop, parentmapper, adapt_to_entity=None):
         self.prop = self.property = prop
         self._parentmapper = parentmapper
-        self.adapter = adapter
+        self._adapt_to_entity = adapt_to_entity
 
     def __clause_element__(self):
         raise NotImplementedError("%r" % self)
 
-    def adapted(self, adapter):
+    def adapt_to_entity(self, adapt_to_entity):
         """Return a copy of this PropComparator which will use the given
-        adaption function on the local side of generated expressions.
-
+        :class:`.AliasedInsp` to produce corresponding expressions.
         """
+        return self.__class__(self.prop, self._parentmapper, adapt_to_entity)
+
+    @property
+    def adapter(self):
+        """Produce a callable that adapts column expressions
+        to suit an aliased version of this comparator.
 
-        return self.__class__(self.prop, self._parentmapper, adapter)
+        """
+        if self._adapt_to_entity is None:
+            return None
+        else:
+            return self._adapt_to_entity._adapt_element
 
     @util.memoized_property
     def info(self):