Shadow Terminal

A fully-functional, fully-rendered terminal purely in memory.

Useful for terminal multiplexers (a la tmux, zellij) and end to end testing TUI applications.

Making a live terminal that automatically updates as you send it input and as any programs running in it send output.

let config = ShadowTerminalConfig::default();
let active_terminal = shadow_terminal::active_terminal::ActiveTerminal::start(config);
active_terminal.send_input(forwarded_stdin_bytes);
let surface = shadow_terminal.surface_output_rx.recv().await;
dbg!(surface);

An example of a basic end to end test using the SteppableTerminal.

let config = ShadowTerminalConfig::default();
let mut stepper = SteppableTerminal::start(config).await.unwrap();
stepper.send_string("echo $((1+1))\n").unwrap();
stepper.wait_for_change().await.unwrap();
let output = stepper.screen_as_string().unwrap();
assert_eq!(
    output,
    indoc::formatdoc! {"
        {prompt} echo $((1+1))
        2
        {prompt} 
    "}
);

Testing

• End to end tests depend on nano (to help text resizing the terminal).

TODO

• Every test has to be marked with #[tokio::test(flavor = "multi_thread")] otherwise tests can hang. I'm not sure why, I'd really like to know.
• If #[tokio::test(flavor = "multi_thread")] is really necessary it'd be nice if there was a way to globally set it for tests.

Notes

• Useful ANSI code resources:
  • https://gist.github.com/ConnerWill/d4b6c776b509add763e17f9f113fd25b
  • https://www.qnx.com/developers/docs/qnx_4.25_docs/qnx4/utils/d/devansi.html