Fix alias handling in has_unique_index

CHANGES.rst

@@ -8,7 +8,7 @@ Here you can see the full list of changes between each SQLAlchemy-Utils release.
 ^^^^^^^^^^^^^^^^^^^
 
 - Made assert_* functions automatically rollback session
-
+- Fix alias handling in has_unique_index
 
 
 0.27.4 (2014-10-23)

sqlalchemy_utils/functions/database.py

@@ -198,8 +198,17 @@ def has_unique_index(column):
         has_unique_index(table.c.is_published) # True
         has_unique_index(table.c.is_deleted)   # False
         has_unique_index(table.c.id)           # True
+
+
+    :raises TypeError: if given column does not belong to a Table object
     """
-    pks = column.table.primary_key.columns
+    table = column.table
+    if not isinstance(table, sa.Table):
+        raise TypeError(
+            'Only columns belonging to Table objects are supported. Given '
+            'column belongs to %r.' % table
+        )
+    pks = table.primary_key.columns
     return (
         (column is pks.values()[0] and len(pks) == 1)
         or

tests/functions/test_has_unique_index.py

@@ -1,10 +1,11 @@
+from pytest import raises
 import sqlalchemy as sa
 from sqlalchemy.ext.declarative import declarative_base
 
 from sqlalchemy_utils import has_unique_index
 
 
-class TestHasIndex(object):
+class TestHasUniqueIndex(object):
     def setup_method(self, method):
         Base = declarative_base()
 
@@ -31,6 +32,11 @@ class TestHasIndex(object):
     def test_primary_key(self):
         assert has_unique_index(self.articles.c.id)
 
+    def test_column_of_aliased_table(self):
+        alias = sa.orm.aliased(self.articles)
+        with raises(TypeError):
+            assert has_unique_index(alias.c.id)
+
     def test_unique_index(self):
         assert has_unique_index(self.article_translations.c.is_deleted)
 

tests/functions/test_make_order_by_deterministic.py

@@ -17,7 +17,6 @@ class TestMakeOrderByDeterministic(TestCase):
                 sa.func.lower(name)
             )
 
-
         class Article(self.Base):
             __tablename__ = 'article'
             id = sa.Column(sa.Integer, primary_key=True)
@@ -31,6 +30,7 @@ class TestMakeOrderByDeterministic(TestCase):
         )
 
         self.User = User
+        self.Article = Article
 
     def test_column_property(self):
         query = self.session.query(self.User).order_by(self.User.email_lower)