Fix payment reference issue with duplicate resolver

members/migrations/0013_auto_20170601_1822.py

@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11 on 2017-06-01 15:22
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('members', '0012_memberconflict'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='payment',
+            name='member',
+            field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.PROTECT, related_name='payments', to='members.Member'),
+        ),
+    ]

members/models.py

@@ -85,7 +85,11 @@ class Payment(models.Model):
         ('bank_transfer', _('Bank transfer')),
     ], max_length=255)
 
-    member = models.ForeignKey('Member', on_delete=models.SET_NULL, blank=True, null=True)
+    member = models.ForeignKey('Member',
+                               on_delete=models.PROTECT,
+                               blank=True,
+                               null=True,
+                               related_name='payments')
 
     def __str__(self):
         return 'Payment no. {}, {}'.format(self.id, str(self.date))

members/views.py

@@ -486,8 +486,14 @@ def resolve_conflict(request, *args, **kwargs):
     second_member = conflict.second_member
 
     if action == 'first':
+        for payment in second_member.payments.all():
+            payment.member = first_member
+            payment.save()
         second_member.delete()
     elif action == 'second':
+        for payment in first_member.payments.all():
+            payment.member = second_member
+            payment.save()
         first_member.delete()
 
     conflict.delete()