annotate parentmapper in primaryjoin / secondaryjoin

this is related to ~~#3365~~ but is a more fundamental change.

First, test case from ~~#3365~~:

from sqlalchemy import Column, Integer, Text, ForeignKey, create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import Session, relationship

Base = declarative_base()


class Parent(Base):
    __tablename__ = "parent"
    id = Column(Integer, primary_key=True)


class Child(Base):
    __tablename__ = "child"
    _id_parent = Column(
        "id_parent", Integer, ForeignKey(Parent.id), primary_key=True)
    name = Column(Text, primary_key=True)
    parent = relationship(Parent)

engine = create_engine('sqlite://')
Base.metadata.create_all(engine)
session = Session(engine)

p = Parent(id=1)
session.add(p)
session.commit()

c = Child(name="foo", parent=p)
session.add(c)
session.commit()

session.query(Child).filter(Child.parent == p).delete("evaluate")

raises: "AttributeError: 'Child' object has no attribute 'id_parent'"

with the fix, raises: "sqlalchemy.exc.InvalidRequestError: Could not evaluate current criteria in Python. Specify 'fetch' or False for the synchronize_session parameter."

the patch involves adding ORM context to the primaryjoin/secondaryjoin:

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.

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