    fn route_messages_empty() {
        let (querier, _, addr) = setup();
        let client: Client =
            client::Client::new(QuerierWrapper::new(&querier), addr.clone()).into();

        let result = client.route_messages(Vec::new());

        assert!(result.is_none(), "Expected None for empty messages vector");
    }
    #[test]
    fn outgoing_messages_no_data() {
        let (querier, _, addr) = setup();
        let client: Client =
            client::Client::new(QuerierWrapper::new(&querier), addr.clone()).into();

        // Create CrossChainId instances explicitly
        let message_ids = vec![
            CrossChainId::new("sourcechain", "non-existent-id").unwrap(),
            CrossChainId::new("sourcechain", "another-non-existent-id").unwrap(),
        ];
        let result = client.outgoing_messages(message_ids);

        assert!(
            result.is_err(),
            "Expected error due to non-existent message IDs"
        );
    }
