diff --git a/tests/test_cli.py b/tests/test_cli.py
index 8368488..9f7aa50 100644
--- a/tests/test_cli.py
+++ b/tests/test_cli.py
@@ -80,6 +80,7 @@ class TestCLIInterface(TestCase):
             """
             Mock server object for testing.
             """
+            abort_start = False
 
             def __init__(self, **kwargs):
                 self.init_kwargs = kwargs