1 #![warn(rust_2018_idioms)]
2 #![cfg(feature = "full")]
3
4 use bytes::BytesMut;
5 use futures::ready;
6 use tokio::io::{self, AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt, ReadBuf};
7 use tokio_test::assert_ok;
8
9 use std::pin::Pin;
10 use std::task::{Context, Poll};
11
12 #[tokio::test]
copy()13 async fn copy() {
14 struct Rd(bool);
15
16 impl AsyncRead for Rd {
17 fn poll_read(
18 mut self: Pin<&mut Self>,
19 _cx: &mut Context<'_>,
20 buf: &mut ReadBuf<'_>,
21 ) -> Poll<io::Result<()>> {
22 if self.0 {
23 buf.put_slice(b"hello world");
24 self.0 = false;
25 Poll::Ready(Ok(()))
26 } else {
27 Poll::Ready(Ok(()))
28 }
29 }
30 }
31
32 let mut rd = Rd(true);
33 let mut wr = Vec::new();
34
35 let n = assert_ok!(io::copy(&mut rd, &mut wr).await);
36 assert_eq!(n, 11);
37 assert_eq!(wr, b"hello world");
38 }
39
40 #[tokio::test]
proxy()41 async fn proxy() {
42 struct BufferedWd {
43 buf: BytesMut,
44 writer: io::DuplexStream,
45 }
46
47 impl AsyncWrite for BufferedWd {
48 fn poll_write(
49 self: Pin<&mut Self>,
50 _cx: &mut Context<'_>,
51 buf: &[u8],
52 ) -> Poll<io::Result<usize>> {
53 self.get_mut().buf.extend_from_slice(buf);
54 Poll::Ready(Ok(buf.len()))
55 }
56
57 fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
58 let this = self.get_mut();
59
60 while !this.buf.is_empty() {
61 let n = ready!(Pin::new(&mut this.writer).poll_write(cx, &this.buf))?;
62 let _ = this.buf.split_to(n);
63 }
64
65 Pin::new(&mut this.writer).poll_flush(cx)
66 }
67
68 fn poll_shutdown(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
69 Pin::new(&mut self.writer).poll_shutdown(cx)
70 }
71 }
72
73 let (rd, wd) = io::duplex(1024);
74 let mut rd = rd.take(1024);
75 let mut wd = BufferedWd {
76 buf: BytesMut::new(),
77 writer: wd,
78 };
79
80 // write start bytes
81 assert_ok!(wd.write_all(&[0x42; 512]).await);
82 assert_ok!(wd.flush().await);
83
84 let n = assert_ok!(io::copy(&mut rd, &mut wd).await);
85
86 assert_eq!(n, 1024);
87 }
88