diff -r 24d4152b0040 Lib/test/test_calendar.py
--- a/Lib/test/test_calendar.py	Mon Mar 23 21:40:43 2015 +0000
+++ b/Lib/test/test_calendar.py	Sun Mar 29 11:06:00 2015 -0400
@@ -753,6 +753,7 @@
                 locale.setlocale(locale.LC_TIME, oldlocale)
         except (locale.Error, ValueError):
             self.skipTest('cannot set the system default locale')
+        self.assertFailure('--locale', lang, '2004')
         stdout = self.run_ok('--locale', lang, '--encoding', enc, '2004')
         self.assertIn('2004'.encode(enc), stdout)