Comment 3 for bug 1530946

so I hacked TestClientInput.clients_receive_keymap_change_events (tests/acceptance_tests/test_client_input.cpp) to do:

 xkb_rule_names names;
  names.rules = nullptr;
  names.model = nullptr;
  names.layout = "us";
  names.variant = nullptr;
  names.options = nullptr;

EXPECT_CALL(first_client, handle_keymap(_))
        .Times(1)
        .WillOnce(mt::WakeUp(&first_client.all_events_received));

server.the_shell()->focused_surface()->set_keymap(names);
first_client.all_events_received.wait_for_at_most_seconds(2);

No crash.

Can you examine xkb_rule_names and list the contents?