Add tests for primary_keys

tests/functions/test_primary_keys.py

@@ -0,0 +1,32 @@
+try:
+    from collections import OrderedDict
+except ImportError:
+    from ordereddict import OrderedDict
+import sqlalchemy as sa
+from sqlalchemy_utils import primary_keys
+from tests import TestCase
+
+
+class TestPrimaryKeys(TestCase):
+    def create_models(self):
+        class Building(self.Base):
+            __tablename__ = 'building'
+            id = sa.Column('_id', sa.Integer, primary_key=True)
+            name = sa.Column('_name', sa.Unicode(255))
+
+        self.Building = Building
+
+    def test_table(self):
+        assert primary_keys(self.Building.__table__) == OrderedDict({
+            '_id': self.Building.__table__.c._id
+        })
+
+    def test_declarative_class(self):
+        assert primary_keys(self.Building) == OrderedDict({
+            'id': self.Building.__table__.c._id
+        })
+
+    def test_declarative_object(self):
+        assert primary_keys(self.Building()) == OrderedDict({
+            'id': self.Building.__table__.c._id
+        })