Revision control

Copy as Markdown

Other Tools

#![warn(rust_2018_idioms)]
#![cfg(feature = "full")]
use tokio::io::{AsyncRead, AsyncReadExt, ReadBuf};
use tokio_test::assert_ok;
use std::io;
use std::pin::Pin;
use std::task::{Context, Poll};
#[tokio::test]
async fn read_buf() {
struct Rd {
cnt: usize,
}
impl AsyncRead for Rd {
fn poll_read(
mut self: Pin<&mut Self>,
_cx: &mut Context<'_>,
buf: &mut ReadBuf<'_>,
) -> Poll<io::Result<()>> {
self.cnt += 1;
buf.put_slice(b"hello world");
Poll::Ready(Ok(()))
}
}
let mut buf = vec![];
let mut rd = Rd { cnt: 0 };
let n = assert_ok!(rd.read_buf(&mut buf).await);
assert_eq!(1, rd.cnt);
assert_eq!(n, 11);
assert_eq!(buf[..], b"hello world"[..]);
}
#[tokio::test]
#[cfg(feature = "io-util")]
async fn issue_5588() {
use bytes::BufMut;
// steps to zero
let mut buf = [0; 8];
let mut read_buf = ReadBuf::new(&mut buf);
assert_eq!(read_buf.remaining_mut(), 8);
assert_eq!(read_buf.chunk_mut().len(), 8);
unsafe {
read_buf.advance_mut(1);
}
assert_eq!(read_buf.remaining_mut(), 7);
assert_eq!(read_buf.chunk_mut().len(), 7);
unsafe {
read_buf.advance_mut(5);
}
assert_eq!(read_buf.remaining_mut(), 2);
assert_eq!(read_buf.chunk_mut().len(), 2);
unsafe {
read_buf.advance_mut(2);
}
assert_eq!(read_buf.remaining_mut(), 0);
assert_eq!(read_buf.chunk_mut().len(), 0);
// directly to zero
let mut buf = [0; 8];
let mut read_buf = ReadBuf::new(&mut buf);
assert_eq!(read_buf.remaining_mut(), 8);
assert_eq!(read_buf.chunk_mut().len(), 8);
unsafe {
read_buf.advance_mut(8);
}
assert_eq!(read_buf.remaining_mut(), 0);
assert_eq!(read_buf.chunk_mut().len(), 0);
// uninit
let mut buf = [std::mem::MaybeUninit::new(1); 8];
let mut uninit = ReadBuf::uninit(&mut buf);
assert_eq!(uninit.remaining_mut(), 8);
assert_eq!(uninit.chunk_mut().len(), 8);
let mut buf = [std::mem::MaybeUninit::uninit(); 8];
let mut uninit = ReadBuf::uninit(&mut buf);
unsafe {
uninit.advance_mut(4);
}
assert_eq!(uninit.remaining_mut(), 4);
assert_eq!(uninit.chunk_mut().len(), 4);
uninit.put_u8(1);
assert_eq!(uninit.remaining_mut(), 3);
assert_eq!(uninit.chunk_mut().len(), 3);
uninit.put_slice(&[1, 2, 3]);
assert_eq!(uninit.remaining_mut(), 0);
assert_eq!(uninit.chunk_mut().len(), 0);
}