diff --git a/Lib/test/test_extcall.py b/Lib/test/test_extcall.py
index a5af50b..cf882a5 100644
--- a/Lib/test/test_extcall.py
+++ b/Lib/test/test_extcall.py
@@ -280,6 +280,12 @@
     Traceback (most recent call last):
       ...
     TypeError: f() takes exactly 1 argument (5 given)
+    >>> def f(a, *, kw):
+    ...    pass
+    >>> f(6, 4, kw=4)
+    Traceback (most recent call last):
+      ...
+    TypeError: f() takes exactly 2 arguments (3 given)
 """
 
 import sys