[FIX] point_of_sale: Correct margin for product with no cost

Current behavior:
In the pos order report the margin is not shown for products with no
cost.

Steps to reproduce:
- Create a product with no cost
- Open a pos session, add the product to the order and validate it
- Go to the pos order report and check the margin for the product
- The margin is not shown

opw-3232131

closes odoo/odoo#117723

X-original-commit: 223400d371615907a7ba7d5616ffeec307892f16
Signed-off-by: Trinh Jacky (trj) <trj@odoo.com>
Signed-off-by: Engels Robin (roen) <roen@odoo.com>

addons/point_of_sale/report/pos_order_report.py

@@ -66,7 +66,7 @@ class PosOrderReport(models.Model):
                 s.pricelist_id,
                 s.session_id,
                 s.account_move IS NOT NULL AS invoiced,
-                SUM(l.price_subtotal - l.total_cost / CASE COALESCE(s.currency_rate, 0) WHEN 0 THEN 1.0 ELSE s.currency_rate END) AS margin
+                SUM(l.price_subtotal - COALESCE(l.total_cost,0) / CASE COALESCE(s.currency_rate, 0) WHEN 0 THEN 1.0 ELSE s.currency_rate END) AS margin
         """
 
     def _from(self):

addons/point_of_sale/tests/__init__.py

@@ -17,4 +17,5 @@ from . import test_pos_other_currency_config
 from . import test_pos_with_fiscal_position
 from . import test_pos_stock_account
 from . import test_js
+from . import test_report_pos_order
 from . import test_res_config_settings

addons/point_of_sale/tests/test_report_pos_order.py

@@ -0,0 +1,41 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+import odoo
+
+from odoo.addons.point_of_sale.tests.common import TestPoSCommon
+
+@odoo.tests.tagged('post_install', '-at_install')
+class TestReportPoSOrder(TestPoSCommon):
+
+    def setUp(self):
+        super(TestReportPoSOrder, self).setUp()
+        self.config = self.basic_config
+
+    def test_report_pos_order(self):
+
+        product1 = self.create_product('Product 1', self.categ_basic, 150)
+
+        self.open_new_session()
+        session = self.pos_session
+
+        self.env['pos.order'].create({
+            'session_id': session.id,
+            'lines': [(0, 0, {
+                'name': "OL/0001",
+                'product_id': product1.id,
+                'price_unit': 150,
+                'discount': 0,
+                'qty': 1.0,
+                'price_subtotal': 150,
+                'price_subtotal_incl': 150,
+            }),],
+            'amount_total': 150.0,
+            'amount_tax': 0.0,
+            'amount_paid': 0.0,
+            'amount_return': 0.0,
+        })
+
+        # PoS Orders have negative IDs to avoid conflict, so reports[0] will correspond to the newest order
+        reports = self.env['report.pos.order'].sudo().search([('product_id', '=', product1.id)], order='id')
+
+        self.assertEqual(reports[0].margin, 150)