[FIX] stock: avoid lot required error when scrapping tracked products without picking

When scrapping a tracked product without a lot and without a picking_type_id,
`stock.move.line._action_done` raises a UserError requiring a lot/serial number.

This happens because the method checks for the absence of both
`picking_type_id`, `is_inventory`, and `lot_id`, assuming a lot is always
mandatory outside inventory and picking flows.

However, scrap operations may occur outside these flows and should not
necessarily require a lot, especially when triggered programmatically
(e.g. via API or automation), bypassing the form view validation.

This commit updates the condition in `_action_done()` to check the context
key `is_scrap`, which is already passed in `do_scrap()` via
`move.with_context(is_scrap=True)._action_done()`.

This allows tracked products to be scrapped without a lot in valid scenarios,
without misleadingly assigning a `picking_type_id` to the move.

closes odoo#213536

X-original-commit: a14c8dc
Signed-off-by: William Henrotin (whe) <[email protected]>

Author: MiquelRForgeFlow

addons/stock/models/stock_move_line.py

@@ -621,7 +621,7 @@ def _action_done(self):
                 if ml.product_id.tracking == 'none':
                     continue
                 picking_type_id = ml.move_id.picking_type_id
-                if not picking_type_id and not ml.is_inventory and not ml.lot_id:
+                if not picking_type_id and not ml.is_inventory and not ml.lot_id and not ml.move_id.scrap_id:
                     ml_ids_tracked_without_lot.add(ml.id)
                     continue
                 if not picking_type_id or ml.lot_id or (not picking_type_id.use_create_lots and not picking_type_id.use_existing_lots):

addons/stock/tests/test_stock_flow.py

@@ -2251,6 +2251,28 @@ def test_stock_move_with_partner_id(self):
         picking.write({'partner_id': partner_2.id})
         self.assertEqual(picking.move_ids.partner_id, partner_2)
 
+    def test_scrap_tracked_product_without_lot(self):
+        """Scrapping a tracked product without lot should not raise
+        if is_scrap context is set."""
+        stock_location = self.StockLocationObj.browse(self.stock_location)
+        tracked_product = self.env['product.product'].create({
+            'name': 'Tracked Product',
+            'type': 'consu',
+            'is_storable': True,
+            'tracking': 'lot',
+        })
+        self.env['stock.quant']._update_available_quantity(tracked_product, stock_location, 1.0)
+
+        scrap = self.env['stock.scrap'].create({
+            'product_id': tracked_product.id,
+            'product_uom_id': tracked_product.uom_id.id,
+            'location_id': self.stock_location,
+            'scrap_qty': 1.0,
+        })
+        scrap.do_scrap()
+
+        self.assertEqual(scrap.move_ids.state, 'done')
+
     def test_cancel_picking_with_scrapped_products(self):
         """
         The user scraps some products of a picking, then cancel this picking