[FIX] point_of_sale: Prevent multiple cash payment method in PoS

Current behavior:
When creating a PoS config, it is possible to have multiple cash payment
method. Wich is not supported by the PoS.

opw-3030125

closes odoo/odoo#109331

X-original-commit: 7ba362b60a38a993fdeec920e6c90a754ddeb910
Signed-off-by: Trinh Jacky (trj) <trj@odoo.com>
Signed-off-by: Engels Robin (roen) <roen@odoo.com>

addons/point_of_sale/i18n/point_of_sale.pot

@@ -6943,6 +6943,13 @@ msgid ""
 "                    Or you can add demo data for testing purpose. Please mind that this is an irreversible action."
 msgstr ""
 
+#. module: point_of_sale
+#. odoo-python
+#: code:addons/point_of_sale/models/pos_config.py:0
+#, python-format
+msgid "You can only have one cash payment method."
+msgstr ""
+
 #. module: point_of_sale
 #: code:addons/point_of_sale/models/pos_session.py:0
 #, python-format

addons/point_of_sale/models/pos_config.py

@@ -180,6 +180,13 @@ class PosConfig(models.Model):
         for config in self:
             config.cash_control = bool(config.payment_method_ids.filtered('is_cash_count'))
 
+    @api.onchange('payment_method_ids')
+    def _check_cash_payment_method(self):
+        for config in self:
+            if len(config.payment_method_ids.filtered('is_cash_count')) > 1:
+                config.payment_method_ids = config.payment_method_ids._origin
+                raise ValidationError(_('You can only have one cash payment method.'))
+
     @api.depends('company_id')
     def _compute_company_has_template(self):
         for config in self: