[FIX] delivery: Error message for unavailable delivery methods

With a fixed price delivery method, the error message was not displayed when
the address doesn't match.

Inspired from function base_on_rule_rate_shipment

The error message was not clear enough.

opw:1879204

addons/delivery/i18n/delivery.pot

@@ -355,6 +355,13 @@ msgstr ""
 msgid "Error: no matching grid."
 msgstr ""
 
+#. module: delivery
+#: code:addons/delivery/models/delivery_carrier.py:206
+#: code:addons/delivery/models/delivery_grid.py:50
+#, python-format
+msgid "Error: this delivery method is not available for this address."
+msgstr ""
+
 #. module: delivery
 #: model:ir.model.fields,field_description:delivery.field_sale_order_delivery_price
 msgid "Estimated Delivery Price"

addons/delivery/models/delivery_carrier.py

@@ -199,6 +199,12 @@ class DeliveryCarrier(models.Model):
             carrier.product_id.list_price = carrier.fixed_price
 
     def fixed_rate_shipment(self, order):
+        carrier = self._match_address(order.partner_shipping_id)
+        if not carrier:
+            return {'success': False,
+                    'price': 0.0,
+                    'error_message': _('Error: this delivery method is not available for this address.'),
+                    'warning_message': False}
         price = self.fixed_price
         if self.company_id.currency_id.id != order.currency_id.id:
             price = self.env['res.currency']._compute(self.company_id.currency_id, order.currency_id, price)

addons/delivery/models/delivery_grid.py

@@ -47,7 +47,7 @@ class ProviderGrid(models.Model):
         if not carrier:
             return {'success': False,
                     'price': 0.0,
-                    'error_message': _('Error: no matching grid.'),
+                    'error_message': _('Error: this delivery method is not available for this address.'),
                     'warning_message': False}
 
         try: