Persist rounding mode with order

src/pretix/base/migrations/0285_cartposition_price_includes_rounding_correction_and_more.py

@@ -73,4 +73,9 @@ class Migration(migrations.Migration):
                 decimal_places=2, default=Decimal("0.00"), max_digits=13
             ),
         ),
+        migrations.AddField(
+            model_name="order",
+            name="tax_rounding_mode",
+            field=models.CharField(default="line", max_length=100),
+        ),
     ]

src/pretix/base/models/orders.py

@@ -81,7 +81,7 @@ from pretix.base.email import get_email_context
 from pretix.base.i18n import language
 from pretix.base.models import Customer, User
 from pretix.base.reldate import RelativeDateWrapper
-from pretix.base.settings import PERSON_NAME_SCHEMES
+from pretix.base.settings import PERSON_NAME_SCHEMES, ROUNDING_MODES
 from pretix.base.signals import allow_ticket_download, order_gracefully_delete
 from pretix.base.timemachine import time_machine_now
 
@@ -324,6 +324,11 @@ class Order(LockModel, LoggedModel):
         # Invoice needs to be re-issued when the order is paid again
         default=False,
     )
+    tax_rounding_mode = models.CharField(
+        max_length=100,
+        choices=ROUNDING_MODES,
+        default="line",
+    )
 
     objects = ScopedManager(OrderQuerySet.as_manager().__class__, organizer='event__organizer')
 

src/pretix/base/services/orders.py

@@ -1039,6 +1039,7 @@ def _create_order(event: Event, *, email: str, positions: List[CartPosition], no
         sales_channel=sales_channel,
         customer=customer,
         valid_if_pending=valid_if_pending,
+        tax_rounding_mode=event.settings.tax_rounding,
     )
     if customer:
         order.email_known_to_work = customer.is_verified
@@ -2751,8 +2752,7 @@ class OrderChangeManager:
         if fee_changed:
             fees = list(self.order.fees.all())
 
-        print("round", positions, fees)
-        changed = apply_rounding(self.order.event.settings.tax_rounding, self.order.event.currency, [*positions, *fees])
+        changed = apply_rounding(self.order.tax_rounding_mode, self.order.event.currency, [*positions, *fees])
         for l in changed:
             if isinstance(l, OrderPosition):
                 l.save(update_fields=[

src/pretix/base/settings.py

@@ -78,6 +78,13 @@ from pretix.control.forms import (
 from pretix.helpers.countries import CachedCountries
 
 
+ROUNDING_MODES = (
+    ('line', _('Rounding every line individually')),
+    ('sum_by_net', _('Rounding by order total, keeping net prices stable')),
+    ('sum_by_gross', _('Rounding by order total, keeping gross prices stable')),
+)
+
+
 def country_choice_kwargs():
     allcountries = list(CachedCountries())
     allcountries.insert(0, ('', _('Select country')))
@@ -473,18 +480,10 @@ DEFAULTS = {
         'form_kwargs': dict(
             label=_("Rounding of taxes"),
             widget=forms.RadioSelect,
-            choices=(
-                ('line', _('Rounding every line individually')),
-                ('sum_by_net', _('Rounding by order total, keeping net prices stable')),
-                ('sum_by_gross', _('Rounding by order total, keeping gross prices stable')),
-            ),
+            choices=ROUNDING_MODES,
         ),
         'serializer_kwargs': dict(
-            choices=(
-                ('line', _('Rounding every line individually')),
-                ('sum_by_net', _('Rounding by order total, keeping net prices stable')),
-                ('sum_by_gross', _('Rounding by order total, keeping gross prices stable')),
-            ),
+            choices=ROUNDING_MODES,
         ),
     },
     'invoice_address_asked': {

src/pretix/control/templates/pretixcontrol/order/index.html

@@ -643,7 +643,7 @@
                                 {% endif %}
                                 {% if django_settings.DEBUG %}
                                     <br/>
-                                    <small>
+                                    <small class="admin-only">
                                         price = {{ line.price|floatformat:2 }}<br>
                                         rounding_correction = {{ line.price_includes_rounding_correction|floatformat:2 }}<br>
                                         tax_value = {{ line.tax_value|floatformat:2 }}<br>
@@ -693,7 +693,7 @@
                                 {% endif %}
                                 {% if django_settings.DEBUG %}
                                     <br/>
-                                    <small>
+                                    <small class="admin-only">
                                         price = {{ fee.value|floatformat:2 }}<br>
                                         rounding_correction = {{ fee.value_includes_rounding_correction|floatformat:2 }}<br>
                                         tax_value = {{ fee.tax_value|floatformat:2 }}<br>
@@ -729,6 +729,10 @@
                         </div>
                         <div class="col-md-3 col-xs-6 col-md-offset-5 price">
                             <strong>{{ items.total|money:event.currency }}</strong>
+                            <br/>
+                            <small class="admin-only">
+                                tax_rounding_mode = {{ order.tax_rounding_mode }}
+                            </small>
                         </div>
                         <div class="clearfix"></div>
                     </div>