sf checkout: Fix scannig a lot and quantity done

With the no-prefill-qty option not set.
When selecting a line by scanning a lot, all the lines with the same
product related to that lot. Have their quantity done set!

But only the line with the lot scanned should have the quantity done
updated.

shopfloor/services/checkout.py

@@ -581,18 +581,18 @@ def _select_lines_from_lot(
         elif packages:
             # Select all the lines of the package when we scan a lot in a
             # package and we have only one.
+
             return self._select_lines_from_package(
                 picking, selection_lines, packages, prefill_qty=prefill_qty, **kw
             )
-
-        first_allowed_line = fields.first(lines)
-        return self._select_lines_from_product(
-            picking,
-            selection_lines,
-            first_allowed_line.product_id,
-            prefill_qty=prefill_qty,
-            check_lot=False,
+        # Not in a package. related lines are all other lines not in a package
+        related_lines = selection_lines.filtered(
+            lambda l: not l.package_id and l.lot_id != lot
         )
+        lines = self._select_lines(
+            lines, prefill_qty=prefill_qty, related_lines=related_lines
+        )
+        return self._response_for_select_package(picking, lines)
 
     def _select_lines_from_serial(self, picking, selection_lines, lot, **kw):
         # Search for serial number is actually the same as searching for lot (as of v14...)

shopfloor/tests/test_checkout_scan_line.py

@@ -110,6 +110,7 @@ def test_scan_line_product_packaging_ok(self):
         )
 
     def test_scan_line_product_lot_ok(self):
+        """Check scanning a lot and there is only one lot for that product."""
         picking = self._create_picking(
             lines=[(self.product_a, 1), (self.product_a, 1), (self.product_b, 1)]
         )
@@ -121,6 +122,30 @@ def test_scan_line_product_lot_ok(self):
         related_lines = picking.move_line_ids - first_line
         self._test_scan_line_ok(lot.name, first_line, related_lines)
 
+    def test_scan_line_product_lot_ok_multiple_lot(self):
+        """Check scanning a lot and there is two different lot for that product."""
+        picking = self._create_picking(
+            lines=[(self.product_a, 1), (self.product_a, 1), (self.product_b, 1)]
+        )
+        # For product A, lets have two lines with different lot
+        lot_1 = self.env["stock.production.lot"].create(
+            {"product_id": self.product_a.id, "company_id": self.env.company.id}
+        )
+        self._update_qty_in_location(
+            picking.location_id, self.product_a, 1, None, lot_1
+        )
+        lot_2 = self.env["stock.production.lot"].create(
+            {"product_id": self.product_a.id, "company_id": self.env.company.id}
+        )
+        self._update_qty_in_location(
+            picking.location_id, self.product_a, 1, None, lot_2
+        )
+        self._fill_stock_for_moves(picking.move_lines[1], in_lot=True)
+        picking.action_assign()
+        line_with_lot_1 = picking.move_line_ids.filtered(lambda l: l.lot_id == lot_1)
+        related_lines = picking.move_line_ids - line_with_lot_1
+        self._test_scan_line_ok(lot_1.name, line_with_lot_1, related_lines)
+
     def test_scan_line_product_in_one_package_all_package_lines_ok(self):
         picking = self._create_picking(
             lines=[(self.product_a, 10), (self.product_b, 10)]