[FIX] delivery_carrier_partner_account - failing collect SO

Fixes a bug where sale orders with a partner_shipping_id not within the
same commercial entity as their partner_id could not have collect
carrier accounts set after being confirmed.

The issue stemmed from the fact that the sale order's recipient_id field
was being set to partner_id, while the created delivery order had
recipient_id set to its partner_id, which is the partner_shipping_id of
the sale order. In other words, the sale order recipient was incorrectly
set to the main partner instead of the shipping address.

This commit adds a test that was previously failing in this scenario. It
also properly sets the recipient_id on the transport selection wizard
and on sale orders themselves, fixing the issue.

delivery_carrier_partner_account/models/sales_order.py

@@ -10,7 +10,7 @@ class SalesOrder(models.Model):
 
     recipient_id = fields.Many2one(
         comodel_name="res.partner",
-        related="partner_id",
+        related="partner_shipping_id",
     )
     sender_id = fields.Many2one(
         comodel_name="res.partner",

delivery_carrier_partner_account/tests/test_sale_order.py

@@ -1,5 +1,6 @@
 from .test_carrier_account_common import TestCarrierAccountCommon
 from odoo.tests import Form
+from odoo import Command
 
 
 class TestSalesOrder(TestCarrierAccountCommon):
@@ -44,6 +45,37 @@ class TestSalesOrder(TestCarrierAccountCommon):
             f"{self.delivery_carrier_1.name} [THIRD PARTY] #{self.third_party_account_1.account_number}",
         )
 
+    def test_sale_order_shipping_to_third_party_collect(self):
+        # We create an order where we are shipping to a third party and the billing mode is collect
+        # This should work, but was previously failing with an error that the carrier account did not belong to the recipient
+        order = self.env["sale.order"].create(
+            {
+                "partner_id": self.client_partner.id,
+                "partner_shipping_id": self.random_partner.id,
+                "order_line": [
+                    Command.create(
+                        {"product_id": self.env.ref("product.product_product_4").id}
+                    )
+                ],
+            }
+        )
+        # Confirming the order is important because the sender and recipient need to be in sync
+        # on the sale order and delivery order. This was the point of failure previously.
+        order.action_confirm()
+
+        wiz = self._get_shipping_wizard(order)
+        with Form(wiz) as form:
+            form.carrier_id = self.delivery_carrier_1
+            form.delivery_billing_mode = "collect"
+        self.assertIn(self.third_party_account_1, wiz.valid_carrier_account_ids)
+        wiz.button_confirm()
+
+        self.assertEqual(
+            order.carrier_account_id.partner_id,
+            self.random_partner,
+            "The carrier account should belong to the recipient (sale order shipping address)",
+        )
+
     def _get_shipping_wizard(self, order):
         wizard_action = order.action_open_delivery_wizard()
         return (

delivery_carrier_partner_account/wizard/choose_delivery_carrier.py

@@ -8,7 +8,7 @@ class ChooseDeliveryCarrier(models.TransientModel):
     _name = "choose.delivery.carrier"
 
     sender_id = fields.Many2one(related="company_id.partner_id")
-    recipient_id = fields.Many2one(related="partner_id")
+    recipient_id = fields.Many2one(related="order_id.partner_shipping_id")
 
     def button_confirm(self):
         vals = {}