errors.txt

error[E0271]: type mismatch resolving `<futures::Map<futures::Receiver<()>, [closure@src/main.rs:118:18: 121:14]> as futures::Future>::Error == ()`
   --> src/main.rs:122:9
    |
122 |         tokio::spawn(signal_handler);
    |         ^^^^^^^^^^^^ expected struct `futures::Canceled`, found ()
    |
    = note: expected type `futures::Canceled`
               found type `()`
    = note: required by `tokio::spawn`

main.rs

fn run(signal_rx: oneshot::Receiver::<()>) -> Result<()> {
    tokio::run(future::lazy(|| {
        // sit on signal_rx until the sender triggers us, but also log when that happens
        let signal_handler = signal_rx
            .map(|sig| {
                info!("we should be closing");
                ()
            });
        tokio::spawn(signal_handler);

        Ok(())
    }));

    Ok(())
}