- A warning is emitted in the case of multiple relationships thatticket_3230

ultimately will populate a foreign key column in conflict with
another, where the relationships are attempting to copy values
from different source columns.  This occurs in the case where
composite foreign keys with overlapping columns are mapped to
relationships that each refer to a different referenced column.
A new documentation section illustrates the example as well as how
to overcome the issue by specifying "foreign" columns specifically
on a per-relationship basis.
fixes #3230

1 files changed, 21 insertions, 18 deletions

diff --git a/test/orm/test_joins.py b/test/orm/test_joins.py
index 40bc01b5d..eba47dbec 100644
--- a/test/orm/test_joins.py
+++ b/test/orm/test_joins.py
@@ -361,6 +361,27 @@ class InheritedJoinTest(fixtures.MappedTest, AssertsCompiledSQL):
         )
 
 
+class JoinOnSynonymTest(_fixtures.FixtureTest, AssertsCompiledSQL):
+    @classmethod
+    def setup_mappers(cls):
+        User = cls.classes.User
+        Address = cls.classes.Address
+        users, addresses = (cls.tables.users, cls.tables.addresses)
+        mapper(User, users, properties={
+            'addresses': relationship(Address),
+            'ad_syn': synonym("addresses")
+        })
+        mapper(Address, addresses)
+
+    def test_join_on_synonym(self):
+        User = self.classes.User
+        self.assert_compile(
+            Session().query(User).join(User.ad_syn),
+            "SELECT users.id AS users_id, users.name AS users_name "
+            "FROM users JOIN addresses ON users.id = addresses.user_id"
+        )
+
+
 class JoinTest(QueryTest, AssertsCompiledSQL):
     __dialect__ = 'default'
 
@@ -409,24 +430,6 @@ class JoinTest(QueryTest, AssertsCompiledSQL):
             sess.query(literal_column('x'), User).join, Address
         )
 
-    def test_join_on_synonym(self):
-
-        class User(object):
-            pass
-        class Address(object):
-            pass
-        users, addresses = (self.tables.users, self.tables.addresses)
-        mapper(User, users, properties={
-            'addresses':relationship(Address),
-            'ad_syn':synonym("addresses")
-        })
-        mapper(Address, addresses)
-        self.assert_compile(
-            Session().query(User).join(User.ad_syn),
-            "SELECT users.id AS users_id, users.name AS users_name "
-            "FROM users JOIN addresses ON users.id = addresses.user_id"
-        )
-
     def test_multi_tuple_form(self):
         """test the 'tuple' form of join, now superseded
         by the two-element join() form.