Revision control
Copy as Markdown
Other Tools
#![warn(rust_2018_idioms)]
#![cfg(feature = "full")]
use futures::task::{Context, Poll};
use std::io::{self, Cursor};
use std::pin::Pin;
use tokio::io::{AsyncSeek, AsyncSeekExt, AsyncWrite, AsyncWriteExt, BufWriter, SeekFrom};
use futures::future;
use tokio_test::assert_ok;
use std::cmp;
use std::io::IoSlice;
mod support {
pub(crate) mod io_vec;
}
use support::io_vec::IoBufs;
struct MaybePending {
inner: Vec<u8>,
ready: bool,
}
impl MaybePending {
fn new(inner: Vec<u8>) -> Self {
Self {
inner,
ready: false,
}
}
}
impl AsyncWrite for MaybePending {
fn poll_write(
mut self: Pin<&mut Self>,
cx: &mut Context<'_>,
buf: &[u8],
) -> Poll<io::Result<usize>> {
if self.ready {
self.ready = false;
Pin::new(&mut self.inner).poll_write(cx, buf)
} else {
self.ready = true;
cx.waker().wake_by_ref();
Poll::Pending
}
}
fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
Pin::new(&mut self.inner).poll_flush(cx)
}
fn poll_shutdown(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
Pin::new(&mut self.inner).poll_shutdown(cx)
}
}
async fn write_vectored<W>(writer: &mut W, bufs: &[IoSlice<'_>]) -> io::Result<usize>
where
W: AsyncWrite + Unpin,
{
let mut writer = Pin::new(writer);
future::poll_fn(|cx| writer.as_mut().poll_write_vectored(cx, bufs)).await
}
#[tokio::test]
async fn buf_writer() {
let mut writer = BufWriter::with_capacity(2, Vec::new());
assert_eq!(writer.write(&[0, 1]).await.unwrap(), 2);
assert_eq!(writer.buffer(), []);
assert_eq!(*writer.get_ref(), [0, 1]);
assert_eq!(writer.write(&[2]).await.unwrap(), 1);
assert_eq!(writer.buffer(), [2]);
assert_eq!(*writer.get_ref(), [0, 1]);
assert_eq!(writer.write(&[3]).await.unwrap(), 1);
assert_eq!(writer.buffer(), [2, 3]);
assert_eq!(*writer.get_ref(), [0, 1]);
writer.flush().await.unwrap();
assert_eq!(writer.buffer(), []);
assert_eq!(*writer.get_ref(), [0, 1, 2, 3]);
assert_eq!(writer.write(&[4]).await.unwrap(), 1);
assert_eq!(writer.write(&[5]).await.unwrap(), 1);
assert_eq!(writer.buffer(), [4, 5]);
assert_eq!(*writer.get_ref(), [0, 1, 2, 3]);
assert_eq!(writer.write(&[6]).await.unwrap(), 1);
assert_eq!(writer.buffer(), [6]);
assert_eq!(*writer.get_ref(), [0, 1, 2, 3, 4, 5]);
assert_eq!(writer.write(&[7, 8]).await.unwrap(), 2);
assert_eq!(writer.buffer(), []);
assert_eq!(*writer.get_ref(), [0, 1, 2, 3, 4, 5, 6, 7, 8]);
assert_eq!(writer.write(&[9, 10, 11]).await.unwrap(), 3);
assert_eq!(writer.buffer(), []);
assert_eq!(*writer.get_ref(), [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]);
writer.flush().await.unwrap();
assert_eq!(writer.buffer(), []);
assert_eq!(*writer.get_ref(), [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]);
}
#[tokio::test]
async fn buf_writer_inner_flushes() {
let mut w = BufWriter::with_capacity(3, Vec::new());
assert_eq!(w.write(&[0, 1]).await.unwrap(), 2);
assert_eq!(*w.get_ref(), []);
w.flush().await.unwrap();
let w = w.into_inner();
assert_eq!(w, [0, 1]);
}
#[tokio::test]
async fn buf_writer_seek() {
let mut w = BufWriter::with_capacity(3, Cursor::new(Vec::new()));
w.write_all(&[0, 1, 2, 3, 4, 5]).await.unwrap();
w.write_all(&[6, 7]).await.unwrap();
assert_eq!(w.seek(SeekFrom::Current(0)).await.unwrap(), 8);
assert_eq!(&w.get_ref().get_ref()[..], &[0, 1, 2, 3, 4, 5, 6, 7][..]);
assert_eq!(w.seek(SeekFrom::Start(2)).await.unwrap(), 2);
w.write_all(&[8, 9]).await.unwrap();
w.flush().await.unwrap();
assert_eq!(&w.into_inner().into_inner()[..], &[0, 1, 8, 9, 4, 5, 6, 7]);
}
#[tokio::test]
async fn maybe_pending_buf_writer() {
let mut writer = BufWriter::with_capacity(2, MaybePending::new(Vec::new()));
assert_eq!(writer.write(&[0, 1]).await.unwrap(), 2);
assert_eq!(writer.buffer(), []);
assert_eq!(&writer.get_ref().inner, &[0, 1]);
assert_eq!(writer.write(&[2]).await.unwrap(), 1);
assert_eq!(writer.buffer(), [2]);
assert_eq!(&writer.get_ref().inner, &[0, 1]);
assert_eq!(writer.write(&[3]).await.unwrap(), 1);
assert_eq!(writer.buffer(), [2, 3]);
assert_eq!(&writer.get_ref().inner, &[0, 1]);
writer.flush().await.unwrap();
assert_eq!(writer.buffer(), []);
assert_eq!(&writer.get_ref().inner, &[0, 1, 2, 3]);
assert_eq!(writer.write(&[4]).await.unwrap(), 1);
assert_eq!(writer.write(&[5]).await.unwrap(), 1);
assert_eq!(writer.buffer(), [4, 5]);
assert_eq!(&writer.get_ref().inner, &[0, 1, 2, 3]);
assert_eq!(writer.write(&[6]).await.unwrap(), 1);
assert_eq!(writer.buffer(), [6]);
assert_eq!(writer.get_ref().inner, &[0, 1, 2, 3, 4, 5]);
assert_eq!(writer.write(&[7, 8]).await.unwrap(), 2);
assert_eq!(writer.buffer(), []);
assert_eq!(writer.get_ref().inner, &[0, 1, 2, 3, 4, 5, 6, 7, 8]);
assert_eq!(writer.write(&[9, 10, 11]).await.unwrap(), 3);
assert_eq!(writer.buffer(), []);
assert_eq!(
writer.get_ref().inner,
&[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]
);
writer.flush().await.unwrap();
assert_eq!(writer.buffer(), []);
assert_eq!(
&writer.get_ref().inner,
&[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]
);
}
#[tokio::test]
async fn maybe_pending_buf_writer_inner_flushes() {
let mut w = BufWriter::with_capacity(3, MaybePending::new(Vec::new()));
assert_eq!(w.write(&[0, 1]).await.unwrap(), 2);
assert_eq!(&w.get_ref().inner, &[]);
w.flush().await.unwrap();
let w = w.into_inner().inner;
assert_eq!(w, [0, 1]);
}
#[tokio::test]
async fn maybe_pending_buf_writer_seek() {
struct MaybePendingSeek {
inner: Cursor<Vec<u8>>,
ready_write: bool,
ready_seek: bool,
seek_res: Option<io::Result<()>>,
}
impl MaybePendingSeek {
fn new(inner: Vec<u8>) -> Self {
Self {
inner: Cursor::new(inner),
ready_write: false,
ready_seek: false,
seek_res: None,
}
}
}
impl AsyncWrite for MaybePendingSeek {
fn poll_write(
mut self: Pin<&mut Self>,
cx: &mut Context<'_>,
buf: &[u8],
) -> Poll<io::Result<usize>> {
if self.ready_write {
self.ready_write = false;
Pin::new(&mut self.inner).poll_write(cx, buf)
} else {
self.ready_write = true;
cx.waker().wake_by_ref();
Poll::Pending
}
}
fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
Pin::new(&mut self.inner).poll_flush(cx)
}
fn poll_shutdown(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
Pin::new(&mut self.inner).poll_shutdown(cx)
}
}
impl AsyncSeek for MaybePendingSeek {
fn start_seek(mut self: Pin<&mut Self>, pos: SeekFrom) -> io::Result<()> {
self.seek_res = Some(Pin::new(&mut self.inner).start_seek(pos));
Ok(())
}
fn poll_complete(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<u64>> {
if self.ready_seek {
self.ready_seek = false;
self.seek_res.take().unwrap_or(Ok(()))?;
Pin::new(&mut self.inner).poll_complete(cx)
} else {
self.ready_seek = true;
cx.waker().wake_by_ref();
Poll::Pending
}
}
}
let mut w = BufWriter::with_capacity(3, MaybePendingSeek::new(Vec::new()));
w.write_all(&[0, 1, 2, 3, 4, 5]).await.unwrap();
w.write_all(&[6, 7]).await.unwrap();
assert_eq!(w.seek(SeekFrom::Current(0)).await.unwrap(), 8);
assert_eq!(
&w.get_ref().inner.get_ref()[..],
&[0, 1, 2, 3, 4, 5, 6, 7][..]
);
assert_eq!(w.seek(SeekFrom::Start(2)).await.unwrap(), 2);
w.write_all(&[8, 9]).await.unwrap();
w.flush().await.unwrap();
assert_eq!(
&w.into_inner().inner.into_inner()[..],
&[0, 1, 8, 9, 4, 5, 6, 7]
);
}
struct MockWriter {
data: Vec<u8>,
write_len: usize,
vectored: bool,
}
impl MockWriter {
fn new(write_len: usize) -> Self {
MockWriter {
data: Vec::new(),
write_len,
vectored: false,
}
}
fn vectored(write_len: usize) -> Self {
MockWriter {
data: Vec::new(),
write_len,
vectored: true,
}
}
fn write_up_to(&mut self, buf: &[u8], limit: usize) -> usize {
let len = cmp::min(buf.len(), limit);
self.data.extend_from_slice(&buf[..len]);
len
}
}
impl AsyncWrite for MockWriter {
fn poll_write(
self: Pin<&mut Self>,
_: &mut Context<'_>,
buf: &[u8],
) -> Poll<Result<usize, io::Error>> {
let this = self.get_mut();
let n = this.write_up_to(buf, this.write_len);
Ok(n).into()
}
fn poll_write_vectored(
self: Pin<&mut Self>,
_: &mut Context<'_>,
bufs: &[IoSlice<'_>],
) -> Poll<Result<usize, io::Error>> {
let this = self.get_mut();
let mut total_written = 0;
for buf in bufs {
let n = this.write_up_to(buf, this.write_len - total_written);
total_written += n;
if total_written == this.write_len {
break;
}
}
Ok(total_written).into()
}
fn is_write_vectored(&self) -> bool {
self.vectored
}
fn poll_flush(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<(), io::Error>> {
Ok(()).into()
}
fn poll_shutdown(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<(), io::Error>> {
Ok(()).into()
}
}
#[tokio::test]
async fn write_vectored_empty_on_non_vectored() {
let mut w = BufWriter::new(MockWriter::new(4));
let n = assert_ok!(write_vectored(&mut w, &[]).await);
assert_eq!(n, 0);
let io_vec = [IoSlice::new(&[]); 3];
let n = assert_ok!(write_vectored(&mut w, &io_vec).await);
assert_eq!(n, 0);
assert_ok!(w.flush().await);
assert!(w.get_ref().data.is_empty());
}
#[tokio::test]
async fn write_vectored_empty_on_vectored() {
let mut w = BufWriter::new(MockWriter::vectored(4));
let n = assert_ok!(write_vectored(&mut w, &[]).await);
assert_eq!(n, 0);
let io_vec = [IoSlice::new(&[]); 3];
let n = assert_ok!(write_vectored(&mut w, &io_vec).await);
assert_eq!(n, 0);
assert_ok!(w.flush().await);
assert!(w.get_ref().data.is_empty());
}
#[tokio::test]
async fn write_vectored_basic_on_non_vectored() {
let msg = b"foo bar baz";
let bufs = [
IoSlice::new(&msg[0..4]),
IoSlice::new(&msg[4..8]),
IoSlice::new(&msg[8..]),
];
let mut w = BufWriter::new(MockWriter::new(4));
let n = assert_ok!(write_vectored(&mut w, &bufs).await);
assert_eq!(n, msg.len());
assert!(w.buffer() == &msg[..]);
assert_ok!(w.flush().await);
assert_eq!(w.get_ref().data, msg);
}
#[tokio::test]
async fn write_vectored_basic_on_vectored() {
let msg = b"foo bar baz";
let bufs = [
IoSlice::new(&msg[0..4]),
IoSlice::new(&msg[4..8]),
IoSlice::new(&msg[8..]),
];
let mut w = BufWriter::new(MockWriter::vectored(4));
let n = assert_ok!(write_vectored(&mut w, &bufs).await);
assert_eq!(n, msg.len());
assert!(w.buffer() == &msg[..]);
assert_ok!(w.flush().await);
assert_eq!(w.get_ref().data, msg);
}
#[tokio::test]
async fn write_vectored_large_total_on_non_vectored() {
let msg = b"foo bar baz";
let mut bufs = [
IoSlice::new(&msg[0..4]),
IoSlice::new(&msg[4..8]),
IoSlice::new(&msg[8..]),
];
let io_vec = IoBufs::new(&mut bufs);
let mut w = BufWriter::with_capacity(8, MockWriter::new(4));
let n = assert_ok!(write_vectored(&mut w, &io_vec).await);
assert_eq!(n, 8);
assert!(w.buffer() == &msg[..8]);
let io_vec = io_vec.advance(n);
let n = assert_ok!(write_vectored(&mut w, &io_vec).await);
assert_eq!(n, 3);
assert!(w.get_ref().data.as_slice() == &msg[..8]);
assert!(w.buffer() == &msg[8..]);
}
#[tokio::test]
async fn write_vectored_large_total_on_vectored() {
let msg = b"foo bar baz";
let mut bufs = [
IoSlice::new(&msg[0..4]),
IoSlice::new(&msg[4..8]),
IoSlice::new(&msg[8..]),
];
let io_vec = IoBufs::new(&mut bufs);
let mut w = BufWriter::with_capacity(8, MockWriter::vectored(10));
let n = assert_ok!(write_vectored(&mut w, &io_vec).await);
assert_eq!(n, 10);
assert!(w.buffer().is_empty());
let io_vec = io_vec.advance(n);
let n = assert_ok!(write_vectored(&mut w, &io_vec).await);
assert_eq!(n, 1);
assert!(w.get_ref().data.as_slice() == &msg[..10]);
assert!(w.buffer() == &msg[10..]);
}
struct VectoredWriteHarness {
writer: BufWriter<MockWriter>,
buf_capacity: usize,
}
impl VectoredWriteHarness {
fn new(buf_capacity: usize) -> Self {
VectoredWriteHarness {
writer: BufWriter::with_capacity(buf_capacity, MockWriter::new(4)),
buf_capacity,
}
}
fn with_vectored_backend(buf_capacity: usize) -> Self {
VectoredWriteHarness {
writer: BufWriter::with_capacity(buf_capacity, MockWriter::vectored(4)),
buf_capacity,
}
}
async fn write_all<'a, 'b>(&mut self, mut io_vec: IoBufs<'a, 'b>) -> usize {
let mut total_written = 0;
while !io_vec.is_empty() {
let n = assert_ok!(write_vectored(&mut self.writer, &io_vec).await);
assert!(n != 0);
assert!(self.writer.buffer().len() <= self.buf_capacity);
total_written += n;
io_vec = io_vec.advance(n);
}
total_written
}
async fn flush(&mut self) -> &[u8] {
assert_ok!(self.writer.flush().await);
&self.writer.get_ref().data
}
}
#[tokio::test]
async fn write_vectored_odd_on_non_vectored() {
let msg = b"foo bar baz";
let mut bufs = [
IoSlice::new(&msg[0..4]),
IoSlice::new(&[]),
IoSlice::new(&msg[4..9]),
IoSlice::new(&msg[9..]),
];
let mut h = VectoredWriteHarness::new(8);
let bytes_written = h.write_all(IoBufs::new(&mut bufs)).await;
assert_eq!(bytes_written, msg.len());
assert_eq!(h.flush().await, msg);
}
#[tokio::test]
async fn write_vectored_odd_on_vectored() {
let msg = b"foo bar baz";
let mut bufs = [
IoSlice::new(&msg[0..4]),
IoSlice::new(&[]),
IoSlice::new(&msg[4..9]),
IoSlice::new(&msg[9..]),
];
let mut h = VectoredWriteHarness::with_vectored_backend(8);
let bytes_written = h.write_all(IoBufs::new(&mut bufs)).await;
assert_eq!(bytes_written, msg.len());
assert_eq!(h.flush().await, msg);
}
#[tokio::test]
async fn write_vectored_large_slice_on_non_vectored() {
let msg = b"foo bar baz";
let mut bufs = [
IoSlice::new(&[]),
IoSlice::new(&msg[..9]),
IoSlice::new(&msg[9..]),
];
let mut h = VectoredWriteHarness::new(8);
let bytes_written = h.write_all(IoBufs::new(&mut bufs)).await;
assert_eq!(bytes_written, msg.len());
assert_eq!(h.flush().await, msg);
}
#[tokio::test]
async fn write_vectored_large_slice_on_vectored() {
let msg = b"foo bar baz";
let mut bufs = [
IoSlice::new(&[]),
IoSlice::new(&msg[..9]),
IoSlice::new(&msg[9..]),
];
let mut h = VectoredWriteHarness::with_vectored_backend(8);
let bytes_written = h.write_all(IoBufs::new(&mut bufs)).await;
assert_eq!(bytes_written, msg.len());
assert_eq!(h.flush().await, msg);
}