feat(scheduling): persist candidate slot ordering

tests/test_response_editing.py

@@ -1180,6 +1180,103 @@ class SchedulingResponseEditingTests(unittest.TestCase):
 
         self.assertEqual(raised.exception.status_code, 409)
 
+    def test_full_edit_reorders_slots_and_poll_options_without_losing_answers(self) -> None:
+        request = self._request(create_participant_invitations=False)
+        self._submit_both(request)
+        first_slot, second_slot = request.slots
+        first_slot.tentative_hold_event_id = "calendar-hold-1"
+        self.session.flush()
+
+        def reconcile_input(
+            slot: SchedulingCandidateSlot,
+        ) -> SchedulingCandidateSlotReconcileInput:
+            return SchedulingCandidateSlotReconcileInput(
+                id=slot.id,
+                revision=scheduling_slot_revision(slot),
+                label=slot.label,
+                description=slot.description,
+                start_at=slot.start_at.replace(tzinfo=timezone.utc),
+                end_at=slot.end_at.replace(tzinfo=timezone.utc),
+                timezone=slot.timezone,
+                location=slot.location,
+                metadata=slot.metadata_ or {},
+            )
+
+        response = api_update_scheduling_request(
+            request.id,
+            SchedulingRequestUpdateRequest(
+                slots=[reconcile_input(second_slot), reconcile_input(first_slot)]
+            ),
+            session=self.session,
+            principal=self._principal(
+                "organizer-1",
+                email=None,
+                scopes={WRITE_SCOPE},
+            ),
+        )
+
+        self.assertEqual(
+            [(slot.id, slot.position) for slot in response.slots],
+            [(second_slot.id, 0), (first_slot.id, 1)],
+        )
+        poll_options = (
+            self.session.query(PollOption)
+            .filter(
+                PollOption.poll_id == request.poll_id,
+                PollOption.deleted_at.is_(None),
+            )
+            .order_by(PollOption.position.asc())
+            .all()
+        )
+        self.assertEqual(
+            [option.id for option in poll_options],
+            [second_slot.poll_option_id, first_slot.poll_option_id],
+        )
+        current = api_get_my_scheduling_availability(
+            request.id,
+            session=self.session,
+            principal=self._principal(
+                "alice-account",
+                email="alice@example.test",
+                scopes={RESPOND_SCOPE},
+            ),
+        )
+        self.assertEqual(
+            {answer.slot_id: answer.value for answer in current.answers},
+            {first_slot.id: "available", second_slot.id: "maybe"},
+        )
+        self.assertEqual(first_slot.tentative_hold_event_id, "calendar-hold-1")
+
+        replayed = api_update_scheduling_request(
+            request.id,
+            SchedulingRequestUpdateRequest(
+                slots=[reconcile_input(second_slot), reconcile_input(first_slot)]
+            ),
+            session=self.session,
+            principal=self._principal(
+                "organizer-1",
+                email=None,
+                scopes={WRITE_SCOPE},
+            ),
+        )
+        self.assertEqual(
+            [(slot.id, slot.position) for slot in replayed.slots],
+            [(second_slot.id, 0), (first_slot.id, 1)],
+        )
+        current = api_get_my_scheduling_availability(
+            request.id,
+            session=self.session,
+            principal=self._principal(
+                "alice-account",
+                email="alice@example.test",
+                scopes={RESPOND_SCOPE},
+            ),
+        )
+        self.assertEqual(
+            {answer.slot_id: answer.value for answer in current.answers},
+            {first_slot.id: "available", second_slot.id: "maybe"},
+        )
+
     def test_draft_edit_does_not_issue_link_for_added_participant(self) -> None:
         request = self._request(
             status="draft",