#15421: fix an OverflowError in Calendar.itermonthdates() after datetime.MAXYEAR.  Patch by Cédric Krier.
diff --git a/Lib/test/test_calendar.py b/Lib/test/test_calendar.py
index 2a56268..5d6549c 100644
--- a/Lib/test/test_calendar.py
+++ b/Lib/test/test_calendar.py
@@ -3,6 +3,7 @@
 
 from test import test_support
 import locale
+import datetime
 
 
 result_2004_text = """
@@ -262,6 +263,11 @@
         new_october = calendar.TextCalendar().formatmonthname(2010, 10, 10)
         self.assertEquals(old_october, new_october)
 
+    def test_itermonthdates(self):
+        # ensure itermonthdates doesn't overflow after datetime.MAXYEAR
+        # see #15421
+        list(calendar.Calendar().itermonthdates(datetime.MAXYEAR, 12))
+
 
 class MonthCalendarTestCase(unittest.TestCase):
     def setUp(self):