Make ItemBundle.designated_price non-nullable

src/pretix/base/migrations/0115_auto_20190323_2238.py

@@ -0,0 +1,24 @@
+# Generated by Django 2.1.7 on 2019-03-23 22:38
+
+from decimal import Decimal
+
+import django.db.models.deletion
+import jsonfallback.fields
+from django.db import migrations, models
+
+import pretix.base.models.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0114_auto_20190316_1014'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='itembundle',
+            name='designated_price',
+            field=models.DecimalField(blank=True, decimal_places=2, default=Decimal('0.00'), help_text="If set, it will be shown that this bundled item is responsible for the given value of the total gross price. This might be important in cases of mixed taxation, but can be kept blank otherwise. This value will NOT be added to the base item's price.", max_digits=10, verbose_name='Designated price part'),
+        ),
+    ]

src/pretix/base/models/items.py

@@ -818,7 +818,7 @@ class ItemBundle(models.Model):
         verbose_name=_('Number')
     )
     designated_price = models.DecimalField(
-        null=True, blank=True,
+        default=Decimal('0.00'), blank=True,
         decimal_places=2, max_digits=10,
         verbose_name=_('Designated price part'),
         help_text=_('If set, it will be shown that this bundled item is responsible for the given value of the total '