SalesOrder Data Migration (#8585)

* Add data migration to remedy bug

* Add migration tests

* Remove faulty migration test

* Tweak filter

* Update migration file

---------

Co-authored-by: Matthias Mair <code@mjmair.com>

src/backend/InvenTree/order/migrations/0105_auto_20241128_0431.py

@@ -0,0 +1,52 @@
+# Generated by Django 4.2.16 on 2024-11-28 04:31
+
+from django.db import migrations
+
+
+def update_shipment_date(apps, schema_editor):
+    """
+    Update the shipment date for existing SalesOrderAllocation objects
+    """
+
+    from order.status_codes import SalesOrderStatusGroups
+
+    SalesOrder = apps.get_model('order', 'SalesOrder')
+
+    # Find any orders which are "complete" but missing a shipment date
+    orders = SalesOrder.objects.filter(
+        status__in=SalesOrderStatusGroups.COMPLETE,
+        shipment_date__isnull=True
+    )
+
+    updated_orders = 0
+
+    for order in orders:
+        # Find the latest shipment date for any associated allocations
+        shipments = order.shipments.filter(shipment_date__isnull=False)
+        latest_shipment = shipments.order_by('-shipment_date').first()
+
+        if not latest_shipment:
+            continue
+
+        # Update the order with the new shipment date
+        order.shipment_date = latest_shipment.shipment_date
+        order.save()
+
+        updated_orders += 1
+    
+    if updated_orders > 0:
+        print(f"Updated {updated_orders} SalesOrder objects with missing shipment_date")
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('order', '0104_alter_returnorderlineitem_quantity'),
+    ]
+
+    operations = [
+        migrations.RunPython(
+            update_shipment_date,
+            reverse_code=migrations.RunPython.noop
+        )
+    ]

src/backend/InvenTree/order/test_migrations.py

@@ -96,7 +96,7 @@ class TestShipmentMigration(MigratorTestCase):
 
         customer = Company.objects.create(
             name='My customer',
-            description='A customer we sell stuff too',
+            description='A customer we sell stuff to',
             is_customer=True,
         )