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#![warn(rust_2018_idioms)]
#![cfg(feature = "full")]
use tokio::io::{join, AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt, Join, ReadBuf};
use std::io;
use std::pin::Pin;
use std::task::{Context, Poll};
struct R;
impl AsyncRead for R {
fn poll_read(
self: Pin<&mut Self>,
_cx: &mut Context<'_>,
buf: &mut ReadBuf<'_>,
) -> Poll<io::Result<()>> {
buf.put_slice(&[b'z']);
Poll::Ready(Ok(()))
}
}
struct W;
impl AsyncWrite for W {
fn poll_write(
self: Pin<&mut Self>,
_cx: &mut Context<'_>,
_buf: &[u8],
) -> Poll<Result<usize, io::Error>> {
Poll::Ready(Ok(1))
}
fn poll_flush(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), io::Error>> {
Poll::Ready(Ok(()))
}
fn poll_shutdown(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), io::Error>> {
Poll::Ready(Ok(()))
}
fn poll_write_vectored(
self: Pin<&mut Self>,
_cx: &mut Context<'_>,
_bufs: &[io::IoSlice<'_>],
) -> Poll<Result<usize, io::Error>> {
Poll::Ready(Ok(2))
}
fn is_write_vectored(&self) -> bool {
true
}
}
#[test]
fn is_send_and_sync() {
fn assert_bound<T: Send + Sync>() {}
assert_bound::<Join<W, R>>();
}
#[test]
fn method_delegation() {
let mut rw = join(R, W);
let mut buf = [0; 1];
tokio_test::block_on(async move {
assert_eq!(1, rw.read(&mut buf).await.unwrap());
assert_eq!(b'z', buf[0]);
assert_eq!(1, rw.write(&[b'x']).await.unwrap());
assert_eq!(
2,
rw.write_vectored(&[io::IoSlice::new(&[b'x'])])
.await
.unwrap()
);
assert!(rw.is_write_vectored());
assert!(rw.flush().await.is_ok());
assert!(rw.shutdown().await.is_ok());
});
}