diff --git a/esileapclient/tests/functional/base.py b/esileapclient/tests/functional/base.py
index 0817347..634b551 100644
--- a/esileapclient/tests/functional/base.py
+++ b/esileapclient/tests/functional/base.py
@@ -121,7 +121,7 @@ def _init_dummy_project(self, name, roles, parent=None):
             'domain': 'default'
         }
 
-        if roles is []:
+        if not roles:
             raise ValueError('No roles specified when initializing dummy \
                               project %s' % name)
         elif type(roles) is str: