fix: revert incorrect Cyrus hint and consolidate calendar wipe logic

The save-load.event.recurrences.exception: unsupported flag added to the
Cyrus hints was wrong — the caldav-server-tester confirms the feature works.
That incorrect flag caused search.py to force server_expand=True on all
expand searches for Cyrus, breaking testTodoDatesearch (VTODO date search
returned 3 instead of 5) and testRecurringDateWithExceptionSearch (RECURRENCE-ID
assertion on server-expanded results).

Also consolidate the wipe-objects logic: Calendar.delete(wipe=True) now handles
per-object NotFoundError, and all three manual "for x in cal.search(): x.delete()"
loops in _cleanup and _fixCalendar are replaced with cal.delete(wipe=True).

prompt: save-load.event.recurrences.exception is found to be working by the caldav-server-tester project. ... Please fix the wipe logic - we should not duplicate it.

AI Prompts:
claude-sonnet-4-6: Please do a code review of the changes since master.  The purpose of this branch is:  * Reduce run-time of tests on github.  They currently take more than an hour.  The tests aren't quick here on my laptop, but they take significantly less time, and test more servers.  I didn't investigate the details, but the tests are still much slower at github than locally. * Deal with test breakages on github.  Tests still break, but now they also fail here at my laptop, I didn't investigate, but it could be the same reason.  The changes causes test breakages:  FAILED tests/test_caldav.py::TestForServerDavical::testRecurringDateWithExceptionSearch - KeyError: 'RECURRENCE-ID' FAILED tests/test_caldav.py::TestForServerCyrus::testTodoDatesearch - assert 3 == 5 FAILED tests/test_caldav.py::TestForServerCyrus::testRecurringDateWithExceptionSearch - KeyError: 'RECURRENCE-ID'
claude-sonnet-4-6: save-load.event.recurrences.exception is found to be working by the caldav-server-tester project.  This is a simple check, so I trust that it's working, and it shouldn't be marked as unsupported in the compatibility_hints.  Perhaps the cyrus docker container run by github has another support matrix than the one run locally, i.e. due to versioning differences?  search.recurrences.expanded.exception is reported to be supported, so it should most likely not be marked as unsupported.  Does cyrus support save-load.event.recurrences.exception, but fails saving and loading a VTODO with recurrence exceptions?  Please check.  Since niquest by now is the default, there should not be any testing on a "Niquests fallback", but we do need testing on a "httpx fallback", so that part of the changeset is good.  Please fix the wipe logic - we should not duplicate it.

Author: tobixen

caldav/collection.py

@@ -804,7 +804,10 @@ def delete(self, wipe=None):
 
         if wipe is True:
             for obj in self.search():
-                obj.delete()
+                try:
+                    obj.delete()
+                except error.NotFoundError:
+                    pass
             return
 
         ## TODO: remove quirk handling from the functional tests
@@ -838,7 +841,10 @@ async def _async_delete(self, wipe=None):
 
         if wipe is True:
             for obj in await self.search():
-                await obj.delete()
+                try:
+                    await obj.delete()
+                except error.NotFoundError:
+                    pass
             return
 
         quirk_info = self.client.features.is_supported("delete-calendar", dict)

caldav/compatibility_hints.py

@@ -1148,10 +1148,6 @@ def dotted_feature_set_list(self, compact=False):
     # Cyrus changes the Schedule-Tag even on attendee PARTSTAT-only updates,
     # violating RFC6638 section 3.2 which requires the tag to remain stable.
     "scheduling.schedule-tag.stable-partstat": {"support": "unsupported"},
-    # Cyrus splits exception VEVENTs (with RECURRENCE-ID) into separate calendar
-    # object resources rather than keeping master+exception together.  Client-side
-    # expansion therefore cannot produce correct RECURRENCE-ID values.
-    "save-load.event.recurrences.exception": {"support": "unsupported"},
     # Cyrus may not properly reject wrong passwords in some configurations.
     # Cyrus implements server-side automatic scheduling: for cross-user invites,
     # the server both auto-processes the invite into the attendee's calendar

tests/test_caldav.py

@@ -1383,25 +1383,15 @@ def _cleanup(self, mode=None):
             return  ## no cleanup needed
         if self.cleanup_regime == "wipe-calendar":
             for cal in self.calendars_used:
-                ## do we need a try-except-pass?
-                try:
-                    for x in cal.search():
-                        x.delete()
-                except error.NotFoundError:
-                    pass
+                cal.delete(wipe=True)
         elif not self.is_supported("create-calendar") or self.cleanup_regime == "thorough":
             for cal in self.calendars_used:
-                for x in cal.search():
-                    x.delete()
+                cal.delete(wipe=True)
             return
         for cal in self.calendars_used:
             if str(cal.url) in self._preconfigured_calendar_urls:
                 ## Pre-configured calendar: wipe objects, don't delete the calendar
-                try:
-                    for x in cal.search():
-                        x.delete()
-                except error.NotFoundError:
-                    pass
+                cal.delete(wipe=True)
             else:
                 cal.delete()
         for calid in (self.testcal_id, self.testcal_id2, self.testcal_id + "-tasks"):
@@ -1438,10 +1428,7 @@ def _teardownCalendar(self, name=None, cal_id=None):
     def _fixCalendar(self, **kwargs):
         cal = self._fixCalendar_(**kwargs)
         if self.cleanup_regime == "wipe-calendar":
-            ## do we need a try-except-pass?
-            ## (if so, consolidate)
-            for x in cal.search():
-                x.delete()
+            cal.delete(wipe=True)
         return cal
 
     def _fixCalendar_(self, **kwargs):