Nicer explanation for missing backend
@@ -293,6 +293,10 @@ class Runner:
self.kill_backend()
configuration = get_workbench().get_option("run.backend_configuration")
backend_name, configuration_option = parse_configuration(configuration)
+ if backend_name not in get_workbench().get_backends():
+ raise UserError("Can't find backend '{}'. Please select another backend from options"
+ .format(backend_name))
+
backend_class = get_workbench().get_backends()[backend_name]
self._proxy = backend_class(configuration_option)
self._set_state("waiting_toplevel_command")
