[FIX] sale: compute price unit on downpayment line

For the moment, the price unit of the down payment line on the sale
order is not always correctly computed. If the price unit is updated on
the down payment invoice, it is not updated on the sale order; or if a
regular invoice is created, the price unit of the down payment is set to
zero on the sale order.

This commit corrects the behavior by using the unit price of the invoice
line.

opw-3140740
opw-3160406
opw-3160420

closes odoo/odoo#114304

X-original-commit: 755c517fcab89df51e8b0ee4529894372b4d4ec1
Signed-off-by: Vallaeys Valentin (vava) <vava@odoo.com>

addons/sale/models/account_move.py

@@ -69,12 +69,7 @@ class AccountMove(models.Model):
 
             try:
                 line.sale_line_ids.tax_id = line.tax_ids
-                if all(line.tax_ids.mapped('price_include')):
-                    line.sale_line_ids.price_unit = line.price_unit
-                else:
-                    #To keep positive amount on the sale order and to have the right price for the invoice
-                    #We need the - before our untaxed_amount_to_invoice
-                    line.sale_line_ids.price_unit = -line.sale_line_ids.untaxed_amount_to_invoice
+                line.sale_line_ids.price_unit = line.price_unit
             except UserError:
                 # a UserError here means the SO was locked, which prevents changing the taxes
                 # just ignore the error - this is a nice to have feature and should not be blocking

addons/sale/tests/test_sale_to_invoice.py

@@ -154,6 +154,48 @@ class TestSaleToInvoice(TestSaleCommon):
         # Validate invoice
         self.sale_order.invoice_ids.action_post()
 
+    def test_downpayment_line_remains_on_SO(self):
+        """ Test downpayment's SO line is created and remains unchanged even if everything is invoiced
+        """
+        # Create the SO with one line
+        sale_order = self.env['sale.order'].with_context(tracking_disable=True).create({
+            'partner_id': self.partner_a.id,
+            'partner_invoice_id': self.partner_a.id,
+            'partner_shipping_id': self.partner_a.id,
+            'pricelist_id': self.company_data['default_pricelist'].id,
+            'order_line': [Command.create({
+                'product_id': self.company_data['product_order_no'].id,
+                'product_uom_qty': 5,
+                'tax_id': False,
+            }),]
+        })
+        # Confirm the SO
+        sale_order.action_confirm()
+        # Update delivered quantity of SO line
+        sale_order.order_line.write({'qty_delivered': 5.0})
+        context = {
+            'active_model': 'sale.order',
+            'active_ids': [sale_order.id],
+            'active_id': sale_order.id,
+            'default_journal_id': self.company_data['default_journal_sale'].id,
+        }
+        # Let's do an invoice for a down payment of 50
+        downpayment = self.env['sale.advance.payment.inv'].with_context(context).create({
+            'advance_payment_method': 'fixed',
+            'fixed_amount': 50,
+            'deposit_account_id': self.company_data['default_account_revenue'].id
+        })
+        downpayment.create_invoices()
+        # Let's do the invoice
+        payment = self.env['sale.advance.payment.inv'].with_context(context).create({
+            'deposit_account_id': self.company_data['default_account_revenue'].id
+        })
+        payment.create_invoices()
+        # Confirm all invoices
+        for invoice in sale_order.invoice_ids:
+            invoice.action_post()
+        downpayment_line = sale_order.order_line.filtered(lambda l: l.is_downpayment and not l.display_type)
+        self.assertEqual(downpayment_line[0].price_unit, 50, 'The down payment unit price should not change on SO')
 
     def test_downpayment_percentage_tax_icl(self):
         """ Test invoice with a percentage downpayment and an included tax