[FIX] purchase: Update correctly the price according to UoM

What are the steps to reproduce your issue ?

    1. Create Product with Purchase Vendor(s) set
    2. Create Units of Measure that are bigger than (10kg/50kg in tests)

What is currently happening ?

    If you put a vendor that is listed in product form, when changing purchase unit from kg to 10/50kg price is updated
    If you put a vendor not listed, it gives cost price which is correct, but does not update price according to unit of measure.

What are you expecting to happen ?

    Update correctly the unit of measure when the vendor is not listed

opw-2494769

closes odoo/odoo#69148

Signed-off-by: William Henrotin <Whenrow@users.noreply.github.com>

2 files changed, 34 insertions, 6 deletions

diff --git a/addons/purchase/models/purchase.py b/addons/purchase/models/purchase.py
index e28ff9e4243..56793330d20 100644
--- a/addons/purchase/models/purchase.py
+++ b/addons/purchase/models/purchase.py
@@ -1058,6 +1058,10 @@ class PurchaseOrderLine(models.Model):
                     self.order_id.company_id,
                     self.date_order or fields.Date.today(),
                 )
+
+            if self.product_uom:
+                price_unit = self.product_id.uom_id._compute_price(price_unit, self.product_uom)
+
             self.price_unit = price_unit
             return
 
diff --git a/addons/purchase_stock/tests/test_onchange_product.py b/addons/purchase_stock/tests/test_onchange_product.py
index dc75bf8ce5c..b029839e035 100644
--- a/addons/purchase_stock/tests/test_onchange_product.py
+++ b/addons/purchase_stock/tests/test_onchange_product.py
@@ -4,7 +4,7 @@
 from datetime import datetime
 
 from odoo import fields
-from odoo.tests.common import TransactionCase
+from odoo.tests.common import TransactionCase, Form
 from odoo.tools import DEFAULT_SERVER_DATETIME_FORMAT
 
 class TestOnchangeProductId(TransactionCase):
@@ -82,16 +82,40 @@ class TestOnchangeProductId(TransactionCase):
         po_line.write({'product_qty': 3, 'product_uom': self.ref("uom.product_uom_dozen")})
         po_line._onchange_quantity()
         self.assertEqual(1200, po_line.price_unit, "Unit price should be 1200 for one Dozen")
-
-        product_ipad = self.env['product.product'].create({'name': 'Conference Chair'})
+        ipad_uom = self.env['uom.category'].create({'name': 'Ipad Unit'})
+        ipad_lot = self.env['uom.uom'].create({
+            'name': 'Ipad',
+            'category_id': ipad_uom.id,
+            'uom_type': 'reference',
+            'rounding': 0.001
+        })
+        ipad_lot_10 = self.env['uom.uom'].create({
+            'name': '10 Ipad',
+            'category_id': ipad_uom.id,
+            'uom_type': 'bigger',
+            'rounding': 0.001,
+            "factor_inv": 10
+        })
+        product_ipad = self.env['product.product'].create({
+            'name': 'Conference Chair',
+            'standard_price': 100,
+            'uom_id': ipad_lot.id,
+            'uom_po_id': ipad_lot.id,
+        })
         po_line2 = self.po_line_model.create({
             'name': product_ipad.name,
             'product_id': product_ipad.id,
             'order_id': po.id,
             'product_qty': 5,
-            'product_uom': uom_id.id,
-            'price_unit': 100.0,
+            'product_uom': ipad_uom.id,
             'date_planned': fields.Date().today()
         })
+
         po_line2.onchange_product_id()
-        self.assertEqual(0, po_line2.price_unit, "No vendor supplies this product, hence unit price should be set to 0")
+        self.assertEqual(100, po_line2.price_unit, "No vendor supplies this product, hence unit price should be set to 100")
+
+        po_form = Form(po)
+        with po_form.order_line.edit(1) as order_line:
+            order_line.product_uom = ipad_lot_10
+        po_form.save()
+        self.assertEqual(1000, po_line2.price_unit, "The product_uom is multiplied by 10, hence unit price should be set to 1000")