def test_error(self):
invalid_values = (None, "asc", "desc", "BBQ")
for invalid_value in invalid_values:
with self.subTest(order_how=invalid_value):
with self.assertRaises(ValueError):
_order_how(Mock(), invalid_value)
def test_desc(self):
column = Mock()
result = _order_how(column, "DESC")
self.assertEqual(result, column.desc())