error.Error.kind

use libtmux::ErrorKind;

// The shape this exists for: use it if it is there, make it if not.
let session = match server.session("work").await? {
    Some(session) => session,
    None => server.new_session("work").await?,
};

// And when an operation races something else removing it. The handle
// is cloned because killing consumes one, which is how the crate
// stops you from using a window you just destroyed.
let window = session.new_window("doomed").await?;
let mut stale = window.clone();
window.kill().await?;

let error = stale.rename("gone").await.expect_err("the window was killed");
assert_eq!(error.kind(), ErrorKind::ObjectGone);
assert!(error.is_object_gone());