[Sqlalchemy-tickets] Issue #3366: annotate parentmapper in primaryjoin / secondaryjoin (zzzeek/sqlalchemy)

[Mike B. <iss...@bi...>]

New issue 3366: annotate parentmapper in primaryjoin / secondaryjoin
https://bitbucket.org/zzzeek/sqlalchemy/issue/3366/annotate-parentmapper-in-primaryjoin

Mike Bayer:

this is related to #3365 but is a more fundamental change:


```
#!diff

diff --git a/lib/sqlalchemy/orm/evaluator.py b/lib/sqlalchemy/orm/evaluator.py
index 1e828ff..fb59186 100644
--- a/lib/sqlalchemy/orm/evaluator.py
+++ b/lib/sqlalchemy/orm/evaluator.py
@@ -59,7 +59,9 @@ class EvaluatorCompiler(object):
                 )
             key = parentmapper._columntoproperty[clause].key
         else:
-            key = clause.key
+            raise UnevaluatableError(
+                "Cannot evaluate column: %s" % clause
+            )
 
         get_corresponding_attr = operator.attrgetter(key)
         return lambda obj: get_corresponding_attr(obj)
diff --git a/lib/sqlalchemy/orm/relationships.py b/lib/sqlalchemy/orm/relationships.py
index b649c9e..291af09 100644
--- a/lib/sqlalchemy/orm/relationships.py
+++ b/lib/sqlalchemy/orm/relationships.py
@@ -1942,6 +1942,7 @@ class JoinCondition(object):
         self._annotate_fks()
         self._annotate_remote()
         self._annotate_local()
+        self._annotate_parentmapper()
         self._setup_pairs()
         self._check_foreign_cols(self.primaryjoin, True)
         if self.secondaryjoin is not None:
@@ -2405,6 +2406,19 @@ class JoinCondition(object):
             self.primaryjoin, {}, locals_
         )
 
+    def _annotate_parentmapper(self):
+        if self.prop is None:
+            return
+
+        def parentmappers_(elem):
+            if "remote" in elem._annotations:
+                return elem._annotate({"parentmapper": self.prop.mapper})
+            elif "local" in elem._annotations:
+                return elem._annotate({"parentmapper": self.prop.parent})
+        self.primaryjoin = visitors.replacement_traverse(
+            self.primaryjoin, {}, parentmappers_
+        )
+
     def _check_remote_side(self):
         if not self.local_remote_pairs:
             raise sa_exc.ArgumentError(
@@ -2811,9 +2825,6 @@ class JoinCondition(object):
 
         bind_to_col = dict((binds[col].key, col) for col in binds)
 
-        # this is probably not necessary
-        lazywhere = _deep_deannotate(lazywhere)
-
         return lazywhere, bind_to_col, equated_columns
 
 

```

We'd just start tracking "parentmapper" throughout all PJ/SJ conditions.