simple/
simple.rs

1use clap::{arg, Parser};
2use faststr::FastStr;
3
4use clap_runner::{CallbackStatus, Context, Dispatcher, Error, RunnableCommand};
5use tokio::io::AsyncWriteExt;
6
7#[derive(Parser, Debug, Default)]
8#[command(name = "rt")]
9struct RootCommand {
10    #[arg(short, long)]
11    debug: bool,
12}
13
14#[async_trait::async_trait]
15impl RunnableCommand for RootCommand {}
16
17#[derive(Parser, Debug, Default)]
18#[command(name = "hi")]
19struct HiCommand {
20    #[arg(short, long)]
21    name: String,
22}
23
24#[async_trait::async_trait]
25impl RunnableCommand for HiCommand {
26    async fn callback(&self, cx: Context) -> Result<CallbackStatus, Error> {
27        cx.write_all(format!("hi {}", self.name).as_bytes())
28            .await
29            .map_err(|e| Error::Unknown(anyhow::anyhow!("write failed {e}")))?;
30        Ok(CallbackStatus::Abort {
31            reason: FastStr::new("done"),
32        })
33    }
34}
35
36#[tokio::main]
37async fn main() -> anyhow::Result<()> {
38    let dispatcher = Dispatcher::new(RootCommand::default())?.register(HiCommand::default())?;
39    // dispatcher.dispatch_with_stdio().await?;
40    let buf = vec![];
41    let w = tokio::io::BufWriter::new(buf);
42    let w = std::sync::Arc::new(tokio::sync::Mutex::new(w));
43    let _cx = dispatcher
44        .dispatch(&["rt", "--debug", "hi", "--name", "me"], w.clone())
45        .await?;
46    w.lock().await.flush().await?;
47    let output = String::from_utf8(w.lock().await.get_ref().to_owned())?;
48    debug_assert_eq!(output, "hi me");
49    println!("{}", output);
50    Ok(())
51}