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#![warn(rust_2018_idioms)]
#![cfg(all(feature = "full", not(target_os = "wasi")))] // Wasi doesn't support bind
use tokio::io::AsyncReadExt;
use tokio::net::TcpStream;
use tokio_test::assert_ok;
use std::thread;
use std::{io::Write, net};
#[tokio::test]
async fn peek() {
let listener = net::TcpListener::bind("127.0.0.1:0").unwrap();
let addr = listener.local_addr().unwrap();
let t = thread::spawn(move || assert_ok!(listener.accept()).0);
let left = net::TcpStream::connect(addr).unwrap();
let mut right = t.join().unwrap();
let _ = right.write(&[1, 2, 3, 4]).unwrap();
let mut left: TcpStream = left.try_into().unwrap();
let mut buf = [0u8; 16];
let n = assert_ok!(left.peek(&mut buf).await);
assert_eq!([1, 2, 3, 4], buf[..n]);
let n = assert_ok!(left.read(&mut buf).await);
assert_eq!([1, 2, 3, 4], buf[..n]);
}