1#![warn(rust_2018_idioms)]
2#![cfg(all(feature = "full", not(target_os = "wasi")))] // Wasi doesn't support bind
3
4use tokio::io::AsyncReadExt;
5use tokio::net::TcpStream;
6
7use tokio_test::assert_ok;
8
9use std::thread;
10use std::{io::Write, net};
11
12#[tokio::test]
13async fn peek() {
14 let listener = net::TcpListener::bind("127.0.0.1:0").unwrap();
15 let addr = listener.local_addr().unwrap();
16 let t = thread::spawn(move || assert_ok!(listener.accept()).0);
17
18 let left = net::TcpStream::connect(addr).unwrap();
19 let mut right = t.join().unwrap();
20 let _ = right.write(&[1, 2, 3, 4]).unwrap();
21
22 let mut left: TcpStream = left.try_into().unwrap();
23 let mut buf = [0u8; 16];
24 let n = assert_ok!(left.peek(&mut buf).await);
25 assert_eq!([1, 2, 3, 4], buf[..n]);
26
27 let n = assert_ok!(left.read(&mut buf).await);
28 assert_eq!([1, 2, 3, 4], buf[..n]);
29}
30