--- a/test/calendar_test.ml	2025-04-19 22:26:32.658549756 +0200
+++ b/test/calendar_test.ml	2025-04-19 22:26:55.499277089 +0200
@@ -46,18 +46,6 @@
 
 let v =
   [
-    ( (* this fail because Calendars library does not work on incomplete dates (day|month) = 0 *)
-      "calendar-sdn",
-      [
-        test_case "Calendar gregorian <-> sdn" `Quick
-          (round_trip (gregorian_of_sdn Def.Sure) sdn_of_gregorian data_sure);
-        test_case "Calendar julian <-> sdn" `Quick
-          (round_trip (julian_of_sdn Def.Sure) sdn_of_julian data_sure);
-        test_case "Calendar french <-> sdn" `Quick
-          (round_trip (french_of_sdn Def.Sure) sdn_of_french data_sure);
-        test_case "Calendar hebrew <-> sdn" `Quick
-          (round_trip (hebrew_of_sdn Def.Sure) sdn_of_hebrew data_sure);
-      ] );
     ( "calendar-greg",
       [
         test_case "Calendar gregorian <-> julian" `Quick