Bump Django to 4.1.* (#2989)

src/pretix/plugins/sendmail/models.py

@@ -21,6 +21,7 @@
 #
 from datetime import datetime, time, timedelta
 
+from dateutil.tz import datetime_exists
 from django.db import models
 from django.db.models import Exists, OuterRef, Q
 from django.utils import timezone
@@ -69,6 +70,9 @@ class ScheduledMail(models.Model):
     def save(self, **kwargs):
         if not self.computed_datetime:
             self.recompute()
+            if 'update_fields' in kwargs:
+                kwargs['update_fields'] = {'computed_datetime', 'last_computed', 'state'}.union(kwargs['update_fields'])
+
         super().save(**kwargs)
 
     def recompute(self):
@@ -88,10 +92,14 @@ class ScheduledMail(models.Model):
             base_time = (e.date_to or e.date_from) if self.rule.offset_to_event_end else e.date_from
             d = base_time.astimezone(self.event.timezone).date() + offset
             self.computed_datetime = make_aware(
-                datetime.combine(d, time(hour=st.hour, minute=st.minute, second=st.second, microsecond=0)),
+                datetime.combine(d, time(hour=st.hour, minute=st.minute, second=st.second, microsecond=0, fold=1)),
                 self.event.timezone,
-                is_dst=False,  # prevent AmbiguousTimeError
             )
+            if not datetime_exists(self.computed_datetime):
+                self.computed_datetime = make_aware(
+                    datetime.combine(d, time(hour=st.hour, minute=st.minute, second=st.second, microsecond=0)) + timedelta(hours=1),
+                    self.event.timezone,
+                )
 
         if self.computed_datetime > timezone.now() and self.state == self.STATE_MISSED:
             self.state = self.STATE_SCHEDULED

src/pretix/plugins/sendmail/urls.py

@@ -32,7 +32,7 @@
 # distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations under the License.
 
-from django.conf.urls import re_path
+from django.urls import re_path
 
 from pretix.api.urls import event_router