fix: Ensure generated lot lines use the stock move's UOM when it differs from the product's base UOM.

models/stock_move.py

@@ -64,6 +64,51 @@ class StockMove(models.Model):
                     # by passing a non-zero base and then overriding the names in the returned list.
                     fake_first = 'SEQDUMMY-1'
                     vals_list = super().action_generate_lot_line_vals(context, mode, fake_first, count, lot_text)
+
+                    # Fix UOM issue: if Move UOM is different from Product UOM,
+                    # the default generation might use Base UOM but with Move's quantity value
+                    move = False
+
+                    # 1. Try finding move via active_id
+                    if context.get('active_id'):
+                        candidate = self.env['stock.move'].browse(context.get('active_id'))
+                        if candidate.exists() and candidate.product_id.id == product_id:
+                            move = candidate
+
+                    # 2. If not found, try finding via context parameters (passed by JS widget)
+                    if not move and product_id:
+                        domain = [
+                            ('product_id', '=', product_id),
+                            ('state', 'not in', ['done', 'cancel']),
+                        ]
+                        if context.get('default_location_id'):
+                            domain.append(('location_id', '=', context.get('default_location_id')))
+                        if context.get('default_location_dest_id'):
+                            domain.append(('location_dest_id', '=', context.get('default_location_dest_id')))
+                        if context.get('default_picking_id'):
+                            domain.append(('picking_id', '=', context.get('default_picking_id')))
+                        elif context.get('active_model') == 'stock.picking' and context.get('active_id'):
+                             domain.append(('picking_id', '=', context.get('active_id')))
+
+                        moves = self.env['stock.move'].search(domain, limit=1)
+                        if moves:
+                            move = moves[0]
+
+                    try:
+                        if move:
+                             move_uom = move.product_uom
+                             base_uom = move.product_id.uom_id
+                             if move_uom and base_uom and move_uom != base_uom:
+                                 # Update all generate lines to use the move's UOM
+                                 # assuming reasonable consistency
+                                 for vals in vals_list:
+                                     # Pass as tuple (id, name) so frontend displays it correctly immediately
+                                     vals['product_uom_id'] = (move_uom.id, move_uom.display_name)
+                    except Exception as e:
+                        # Use a safe logger if available, otherwise just print to not break flow
+                        import logging
+                        _logger = logging.getLogger(__name__)
+                        _logger.error(f"Error fixing UOM in product_lot_sequence_per_product: {e}")
                     # Overwrite the lot_name with sequence-based names; keep all other computed values (uom, putaway).
                     for vals, name in zip(vals_list, generated_names):
                         vals['lot_name'] = name