diff --git a/Lib/test/test_tcl.py b/Lib/test/test_tcl.py
index 28da2dd..2eeabc1 100644
--- a/Lib/test/test_tcl.py
+++ b/Lib/test/test_tcl.py
@@ -129,7 +129,9 @@
         import os
         old_display = None
         import sys
-        if sys.platform.startswith('win') or sys.platform.startswith('darwin'):
+        if (sys.platform.startswith('win') or
+                sys.platform.startswith('darwin') or
+                sys.platform.startswith('cygwin')):
             return # no failure possible on windows?
         if 'DISPLAY' in os.environ:
             old_display = os.environ['DISPLAY']