Bug fix: Update child/parent relationship when a StockItem is deleted

- Pass the child items up to the parent of the deleted item
- Fix unit tests

InvenTree/stock/models.py

@@ -552,7 +552,13 @@ class StockItem(MPTTModel):
         new_stock.pk = None
         new_stock.parent = self
         new_stock.quantity = quantity
-        new_stock.location = location
+
+        # Move to the new location if specified, otherwise use current location
+        if location:
+            new_stock.location = location
+        else:
+            new_stock.location = self.location
+
         new_stock.save()
 
         # Copy the transaction history of this part into the new one
@@ -606,7 +612,7 @@ class StockItem(MPTTModel):
             # Split the existing StockItem in two
             self.splitStock(quantity, location, user)
 
-            return
+            return True
 
         msg = "Moved to {loc}".format(loc=str(location))
 
@@ -757,6 +763,23 @@ class StockItem(MPTTModel):
         return s
 
 
+@receiver(pre_delete, sender=StockItem, dispatch_uid='stock_item_pre_delete_log')
+def before_delete_stock_item(sender, instance, using, **kwargs):
+    """ Receives pre_delete signal from StockItem object.
+
+    Before a StockItem is deleted, ensure that each child object is updated,
+    to point to the new parent item.
+    """
+
+    # Update each StockItem parent field
+    for child in instance.children.all():
+        child.parent = instance.parent
+        child.save()
+
+    # Rebuild the MPTT tree
+    StockItem.objects.rebuild()
+
+
 class StockItemTracking(models.Model):
     """ Stock tracking entry - breacrumb for keeping track of automated stock transactions
 

InvenTree/stock/tests.py

@@ -156,7 +156,9 @@ class StockTest(TestCase):
 
         # Move 6 of the units
         self.assertTrue(w1.move(self.diningroom, 'Moved', None, quantity=6))
-        self.assertEqual(w1.quantity, 6)
+
+        # There should be 4 remaining
+        self.assertEqual(w1.quantity, 4)
 
         # There should also be a new object still in drawer3
         self.assertEqual(StockItem.objects.filter(part=25).count(), 4)
@@ -175,17 +177,17 @@ class StockTest(TestCase):
         N = StockItem.objects.filter(part=3).count()
 
         stock = StockItem.objects.get(id=1234)
-        stock.splitStock(1000, None)
+        stock.splitStock(1000, None, self.user)
         self.assertEqual(stock.quantity, 234)
 
         # There should be a new stock item too!
         self.assertEqual(StockItem.objects.filter(part=3).count(), N + 1)
 
         # Try to split a negative quantity
-        stock.splitStock(-10, None)
+        stock.splitStock(-10, None, self.user)
         self.assertEqual(StockItem.objects.filter(part=3).count(), N + 1)
 
-        stock.splitStock(stock.quantity, None)
+        stock.splitStock(stock.quantity, None, self.user)
         self.assertEqual(StockItem.objects.filter(part=3).count(), N + 1)
 
     def test_stocktake(self):