diff --git a/tests/test_plugins/test_runroot_builder.py b/tests/test_plugins/test_runroot_builder.py
index e63af95f..8924840a 100644
--- a/tests/test_plugins/test_runroot_builder.py
+++ b/tests/test_plugins/test_runroot_builder.py
@@ -75,7 +75,7 @@ class FakeConfigParser(object):
         else:
             self.CONFIG = copy.deepcopy(config)
 
-    def read(self, path, encoding):
+    def read(self, path, encoding=None):
         return
 
     def sections(self):