Introduce cancellation requests (#1627)

* Allow to adjust the cancellation fee without JS

* Introduce cancellation requests

* ignore→delete

* Change a few things after Martin's review

* Add a few tests

src/pretix/control/forms/event.py

@@ -567,6 +567,7 @@ class CancelSettingsForm(SettingsForm):
         'cancel_allow_user_paid_keep_percentage',
         'cancel_allow_user_paid_adjust_fees',
         'cancel_allow_user_paid_refund_as_giftcard',
+        'cancel_allow_user_paid_require_approval',
     ]
 
 

src/pretix/control/forms/filter.py

@@ -220,6 +220,7 @@ class EventOrderFilterForm(OrderFilterForm):
             ('underpaid', _('Underpaid')),
             ('pendingpaid', _('Pending (but fully paid)')),
             ('testmode', _('Test mode')),
+            ('rc', _('Cancellation requested')),
         ),
         required=False,
     )
@@ -305,6 +306,10 @@ class EventOrderFilterForm(OrderFilterForm):
                 Q(~Q(status=Order.STATUS_CANCELED) & Q(pending_sum_t__lt=0))
                 | Q(Q(status=Order.STATUS_CANCELED) & Q(pending_sum_rc__lt=0))
             )
+        elif fdata.get('status') == 'rc':
+            qs = qs.filter(
+                cancellation_requests__isnull=False
+            )
         elif fdata.get('status') == 'pendingpaid':
             qs = Order.annotate_overpayments(qs, refunds=False, results=False, sums=True)
             qs = qs.filter(