[ADD] account_cash_discount_write_off: add function for inheritance t…

…o be able to change discount percentange

account_cash_discount_write_off/models/account_payment_line.py

@@ -1,7 +1,7 @@
 # Copyright 2018 ACSONE SA/NV
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
 
-from odoo import _, models
+from odoo import _, api, models
 from odoo.exceptions import UserError
 from odoo.tools import float_compare, float_is_zero, float_round
 
@@ -41,6 +41,11 @@ def _check_cash_discount_write_off_creation(self):
             == 0
         )
 
+    @api.model
+    def _get_tax_invoice_tax_percentage(self, tax_move_line):
+        tax_invoice = tax_move_line.move_id
+        return tax_invoice.discount_percent
+
     def get_cash_discount_writeoff_move_values(self):
         self.ensure_one()
         move_line = self.move_line_id
@@ -98,10 +103,11 @@ def get_cash_discount_writeoff_move_values(self):
                 ]
             )
 
-            for tax_move_line in tax_move_lines:
-                tax_invoice = tax_move_line.move_id
+            for tax_move_line in tax_move_lines:      
                 amount = float_round(
-                    abs(tax_move_line.balance) * tax_invoice.discount_percent / 100.0,
+                    abs(tax_move_line.balance)
+                    * self._get_tax_invoice_tax_percentage(tax_move_line)
+                    / 100.0,
                     precision_rounding=rounding,
                 )
                 if tax_move_line.credit > 0: