[FIX] sale: forbid pricelist changes on confirmed orders

It cannot happen through the default SO form view, but some funny guys
have found other ways to do it, even though it can be quite problematic,
especially if the new pricelist is in another currency.

X-original-commit: dc7b75f

addons/sale/i18n/sale.pot

@@ -4833,6 +4833,13 @@ msgstr ""
 msgid "You cannot cancel a locked order. Please unlock it first."
 msgstr ""
 
+#. module: sale
+#. odoo-python
+#: code:addons/sale/models/sale_order.py:0
+#, python-format
+msgid "You cannot change the pricelist of a confirmed order !"
+msgstr ""
+
 #. module: sale
 #. odoo-python
 #: code:addons/sale/models/product_product.py:0

addons/sale/models/sale_order.py

@@ -795,6 +795,8 @@ def _unlink_except_draft_or_cancel(self):
                     " You must first cancel it."))
 
     def write(self, vals):
+        if 'pricelist_id' in vals and any(so.state == 'sale' for so in self):
+            raise UserError(_("You cannot change the pricelist of a confirmed order !"))
         res = super().write(vals)
         if vals.get('partner_id'):
             self.filtered(lambda so: so.state in ('sent', 'sale')).message_subscribe(