os.path.listdir -> os.listdir
diff --git a/Lib/importlib/test/util.py b/Lib/importlib/test/util.py
index 0fe31a1..aa5aab2 100644
--- a/Lib/importlib/test/util.py
+++ b/Lib/importlib/test/util.py
@@ -10,7 +10,7 @@
     """Class decorator that nullifies tests that require a case-insensitive
     file system."""
     if sys.platform not in ('win32', 'darwin', 'cygwin'):
-        original_name = os.path.listdir('.')[0]
+        original_name = os.listdir('.')[0]
         if name.upper() != name:
             changed_name = name.upper()
         else: