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    use crate::io::{AsyncRead, ReadBuf};

    use pin_project_lite::pin_project;
    use std::future::Future;
    use std::io;
    use std::marker::PhantomPinned;
    use std::marker::Unpin;
    use std::pin::Pin;
    use std::task::{Context, Poll};

    /// Tries to read some bytes directly into the given `buf` in asynchronous
    /// manner, returning a future type.
    ///
    /// The returned future will resolve to both the I/O stream and the buffer
    /// as well as the number of bytes read once the read operation is completed.
    pub(crate) fn read<'a, R>(reader: &'a mut R, buf: &'a mut [u8]) -> Read<'a, R>
    where
        R: AsyncRead + Unpin + ?Sized,
    {
        Read {
            reader,
            buf,
            _pin: PhantomPinned,
        }
    }

    pin_project! {
        /// A future which can be used to easily read available number of bytes to fill
        /// a buffer.
        ///
        /// Created by the [`read`] function.
        #[derive(Debug)]
        #[must_use = "futures do nothing unless you `.await` or poll them"]
        pub struct Read<'a, R: ?Sized> {
            reader: &'a mut R,
            buf: &'a mut [u8],
            // Make this future `!Unpin` for compatibility with async trait methods.
            #[pin]
            _pin: PhantomPinned,
        }
    }

    impl<R> Future for Read<'_, R>
    where
        R: AsyncRead + Unpin + ?Sized,
    {
        type Output = io::Result<usize>;

        fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<usize>> {
            let me = self.project();
            let mut buf = ReadBuf::new(*me.buf);
            ready!(Pin::new(me.reader).poll_read(cx, &mut buf))?;
            Poll::Ready(Ok(buf.filled().len()))
        }
    }