diff --git a/dist/pythonlibs/riotctrl_shell/tests/common.py b/dist/pythonlibs/riotctrl_shell/tests/common.py
index 342fb1be74..b7d6d6b689 100644
--- a/dist/pythonlibs/riotctrl_shell/tests/common.py
+++ b/dist/pythonlibs/riotctrl_shell/tests/common.py
@@ -14,6 +14,7 @@ class MockSpawn():
         # set some expected attributes
         self.before = None
         self.echo = False
+        self.expect_res = 0
 
     @property
     def last_command(self):
@@ -42,6 +43,9 @@ class MockSpawn():
         # always match on prompt with replwrap
         return 0
 
+    def expect(self, *args, **kwargs):
+        return self.expect_res
+
 
 class MockRIOTCtrl():
     """