- Fixed an 0.9 regression where the automatic aliasing applied by

:class:`.Query` and in other situations where selects or joins
were aliased (such as joined table inheritance) could fail if a
user-defined :class:`.Column` subclass were used in the expression.
In this case, the subclass would fail to propagate ORM-specific
"annotations" along needed by the adaptation.  The "expression
annotations" system has been corrected to account for this case.
[ticket:2918]

1 files changed, 36 insertions, 0 deletions

diff --git a/test/orm/inheritance/test_assorted_poly.py b/test/orm/inheritance/test_assorted_poly.py
index da0e3b1a3..c3ed73c9c 100644
--- a/test/orm/inheritance/test_assorted_poly.py
+++ b/test/orm/inheritance/test_assorted_poly.py
@@ -1521,3 +1521,39 @@ class Ticket2419Test(fixtures.DeclarativeMappedTest):
             q.all(),
             [(b, True)]
         )
+
+class ColSubclassTest(fixtures.DeclarativeMappedTest, testing.AssertsCompiledSQL):
+    """Test [ticket:2918]'s test case."""
+
+    run_create_tables = None
+    __dialect__ = 'default'
+
+    @classmethod
+    def setup_classes(cls):
+        from sqlalchemy.schema import Column
+        Base = cls.DeclarativeBasic
+
+        class A(Base):
+            __tablename__ = 'a'
+
+            id = Column(Integer, primary_key=True)
+
+        class MySpecialColumn(Column):
+            pass
+
+        class B(A):
+            __tablename__ = 'b'
+
+            id = Column(ForeignKey('a.id'), primary_key=True)
+            x = MySpecialColumn(String)
+
+    def test_polymorphic_adaptation(self):
+        A, B = self.classes.A, self.classes.B
+
+        s = Session()
+        self.assert_compile(
+            s.query(A).join(B).filter(B.x == 'test'),
+            "SELECT a.id AS a_id FROM a JOIN "
+            "(a AS a_1 JOIN b AS b_1 ON a_1.id = b_1.id) "
+            "ON a.id = b_1.id WHERE b_1.x = :x_1"
+        )