From a241eb3f96d6e286c1ec95c57ccac92d31fbb1e1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A9dric=20Krier?= <ced@b2ck.com>
Date: Sat, 6 Jan 2024 01:32:52 +0100
Subject: [PATCH] Group only customer shipment by cost method

The return shipment does not have this field.

Closes #12842
---
 modules/sale_shipment_cost/sale.py | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/modules/sale_shipment_cost/sale.py b/modules/sale_shipment_cost/sale.py
index 6d6226f375..6d61d270d4 100644
--- a/modules/sale_shipment_cost/sale.py
+++ b/modules/sale_shipment_cost/sale.py
@@ -368,8 +368,13 @@ class Sale(metaclass=PoolMeta):
         return cost_line
 
     def _get_shipment_grouping_fields(self, shipment):
-        return super()._get_shipment_grouping_fields(shipment) + [
-            'cost_method', 'carrier']
+        pool = Pool()
+        ShipmentOut = pool.get('stock.shipment.out')
+        fields = super()._get_shipment_grouping_fields(shipment)
+        fields.append('carrier')
+        if isinstance(shipment, ShipmentOut):
+            fields.append('cost_method')
+        return fields
 
     @property
     def shipment_cost_amount(self):