Fix CCS (Apple CalendarServer) test failures

- Add CCS compatibility hints: save.duplicate-uid.cross-calendar and
  save-load.todo.recurrences.thisandfuture as unsupported
- Add old-dates skip checks to 4 search tests that use hardcoded dates
  older than CCS min-date-time allows (~1 year)
- Use separate calendar ID for VTODO-only calendars in _fixCalendar_ to
  avoid reusing a VEVENT-only calendar on servers with wipe-calendar
  cleanup regime
- Update teardown to clean up the -tasks calendar variant

CCS tests now: 40 passed, 15 skipped, 0 failed (was 7 failures).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: tobixen

caldav/compatibility_hints.py

@@ -1277,6 +1277,10 @@ def dotted_feature_set_list(self, compact=False):
 ccs = {
     "save-load.journal": {"support": "unsupported"},
     "save-load.todo.mixed-calendar": {"support": "unsupported"},
+    # CCS enforces unique UIDs across ALL calendars for a user
+    "save.duplicate-uid.cross-calendar": {"support": "unsupported"},
+    # CCS rejects multi-instance VTODOs (thisandfuture recurring completion)
+    "save-load.todo.recurrences.thisandfuture": {"support": "unsupported"},
     "search.time-range.event": {"support": "full"},
     "search.time-range.event.old-dates": {"support": "ungraceful"},
     "search.time-range.todo": {"support": "full"},

tests/test_caldav.py

@@ -877,10 +877,17 @@ def _cleanup(self, mode=None):
             cal.delete()
         if self.check_compatibility_flag("unique_calendar_ids") and mode == "pre":
             a = self._teardownCalendar(name="Yep")
-        for calid in (self.testcal_id, self.testcal_id2):
+        for calid in (self.testcal_id, self.testcal_id2, self.testcal_id + "-tasks"):
             self._teardownCalendar(cal_id=calid)
         if self.cleanup_regime == "thorough":
-            for name in ("Yep", "Yapp", "Yølp", self.testcal_id, self.testcal_id2):
+            for name in (
+                "Yep",
+                "Yapp",
+                "Yølp",
+                self.testcal_id,
+                self.testcal_id2,
+                self.testcal_id + "-tasks",
+            ):
                 self._teardownCalendar(name=name)
                 self._teardownCalendar(cal_id=name)
 
@@ -945,7 +952,15 @@ def _fixCalendar_(self, **kwargs):
                 else:
                     kwargs["name"] = "Yep"
             if "cal_id" not in kwargs:
-                kwargs["cal_id"] = self.testcal_id
+                # Use a separate calendar for non-VEVENT component sets
+                # (e.g. VTODO-only) to avoid reusing a VEVENT-only calendar
+                # on servers where MKCALENDAR "already exists" falls through
+                # to the existing calendar with the wrong component set.
+                comp_set = kwargs.get("supported_calendar_component_set", [])
+                if comp_set and "VEVENT" not in comp_set:
+                    kwargs["cal_id"] = self.testcal_id + "-tasks"
+                else:
+                    kwargs["cal_id"] = self.testcal_id
             try:
                 ret = self.principal.make_calendar(**kwargs)
             except (error.MkcalendarError, error.AuthorizationError):
@@ -1737,6 +1752,7 @@ def testGetSupportedComponents(self):
     def testSearchEvent(self):
         self.skip_unless_support("save-load.event")
         self.skip_unless_support("search")
+        self.skip_unless_support("search.time-range.event.old-dates")
         c = self._fixCalendar()
 
         num_existing = len(c.get_events())
@@ -2564,6 +2580,7 @@ def testTodoDatesearch(self):
         """
         self.skip_unless_support("save-load.todo")
         self.skip_unless_support("search.time-range.todo")
+        self.skip_unless_support("search.time-range.todo.old-dates")
         c = self._fixCalendar(supported_calendar_component_set=["VTODO"])
 
         # add todo-item
@@ -3100,6 +3117,7 @@ def testDateSearchAndFreeBusy(self):
         """
         self.skip_unless_support("save-load.event")
         self.skip_unless_support("search")
+        self.skip_unless_support("search.time-range.event.old-dates")
         # Create calendar, add event ...
         c = self._fixCalendar()
         assert c.url is not None
@@ -3292,6 +3310,7 @@ def testRecurringDateSearch(self):
 
     def testRecurringDateWithExceptionSearch(self):
         self.skip_unless_support("search")
+        self.skip_unless_support("search.time-range.event.old-dates")
         c = self._fixCalendar()
 
         # evr2 is a bi-weekly event starting 2024-04-11