Don't project if you require Unpin.

This doesn't make sense. For Unpin types, Pin does nothing, so Pin::new() is sufficient.

However Pin::new is only implemented for `Pin<P> where <P as Deref>::Target: Unpin`, so if it weren't Unpin,
you would have to use unsafe { Pin::new_unchecked(s) }, `Pin::new()` wouldn't compile.

Thus project and Pin::new together is always a code smell.

src/handshake.rs

@@ -2,7 +2,6 @@ use crate::compat::{AllowStd, SetWaker};
 use crate::WebSocketStream;
 use futures::io::{AsyncRead, AsyncWrite};
 use log::*;
-use pin_project::pin_project;
 use std::future::Future;
 use std::io::{Read, Write};
 use std::pin::Pin;
@@ -51,7 +50,6 @@ where
     }
 }
 
-#[pin_project]
 struct MidHandshake<Role: HandshakeRole>(Option<WsHandshake<Role>>);
 
 enum StartedHandshake<Role: HandshakeRole> {
@@ -68,7 +66,7 @@ struct StartedHandshakeFutureInner<F, S> {
 async fn handshake<Role, F, S>(stream: S, f: F) -> Result<Role::FinalResult, Error<Role>>
 where
     Role: HandshakeRole + Unpin,
-    Role::InternalStream: SetWaker,
+    Role::InternalStream: SetWaker + Unpin,
     F: FnOnce(AllowStd<S>) -> Result<Role::FinalResult, Error<Role>> + Unpin,
     S: AsyncRead + AsyncWrite + Unpin,
 {
@@ -145,13 +143,12 @@ where
 impl<Role> Future for MidHandshake<Role>
 where
     Role: HandshakeRole + Unpin,
-    Role::InternalStream: SetWaker,
+    Role::InternalStream: SetWaker + Unpin,
 {
     type Output = Result<Role::FinalResult, Error<Role>>;
 
-    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
-        let this = self.project();
-        let mut s = this.0.take().expect("future polled after completion");
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        let mut s = self.as_mut().0.take().expect("future polled after completion");
 
         let machine = s.get_mut();
         trace!("Setting context in handshake");
@@ -161,7 +158,7 @@ where
             Ok(stream) => Poll::Ready(Ok(stream)),
             Err(Error::Failure(e)) => Poll::Ready(Err(Error::Failure(e))),
             Err(Error::Interrupted(mid)) => {
-                *this.0 = Some(mid);
+                self.0 = Some(mid);
                 Poll::Pending
             }
         }

src/stream.rs

@@ -3,30 +3,26 @@
 //!  There is no dependency on actual TLS implementations. Everything like
 //! `native_tls` or `openssl` will work as long as there is a TLS stream supporting standard
 //! `AsyncRead + AsyncWrite` traits.
-use pin_project::{pin_project, project};
 use std::pin::Pin;
 use std::task::{Context, Poll};
 
 use futures::io::{AsyncRead, AsyncWrite};
 
 /// Stream, either plain TCP or TLS.
-#[pin_project]
 pub enum Stream<S, T> {
     /// Unencrypted socket stream.
-    Plain(#[pin] S),
+    Plain(S),
     /// Encrypted socket stream.
-    Tls(#[pin] T),
+    Tls(T),
 }
 
 impl<S: AsyncRead + Unpin, T: AsyncRead + Unpin> AsyncRead for Stream<S, T> {
-    #[project]
     fn poll_read(
         self: Pin<&mut Self>,
         cx: &mut Context<'_>,
         buf: &mut [u8],
     ) -> Poll<std::io::Result<usize>> {
-        #[project]
-        match self.project() {
+        match self.get_mut() {
             Stream::Plain(ref mut s) => Pin::new(s).poll_read(cx, buf),
             Stream::Tls(ref mut s) => Pin::new(s).poll_read(cx, buf),
         }
@@ -34,32 +30,26 @@ impl<S: AsyncRead + Unpin, T: AsyncRead + Unpin> AsyncRead for Stream<S, T> {
 }
 
 impl<S: AsyncWrite + Unpin, T: AsyncWrite + Unpin> AsyncWrite for Stream<S, T> {
-    #[project]
     fn poll_write(
         self: Pin<&mut Self>,
         cx: &mut Context<'_>,
         buf: &[u8],
     ) -> Poll<Result<usize, std::io::Error>> {
-        #[project]
-        match self.project() {
+        match self.get_mut() {
             Stream::Plain(ref mut s) => Pin::new(s).poll_write(cx, buf),
             Stream::Tls(ref mut s) => Pin::new(s).poll_write(cx, buf),
         }
     }
 
-    #[project]
     fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), std::io::Error>> {
-        #[project]
-        match self.project() {
+        match self.get_mut() {
             Stream::Plain(ref mut s) => Pin::new(s).poll_flush(cx),
             Stream::Tls(ref mut s) => Pin::new(s).poll_flush(cx),
         }
     }
 
-    #[project]
     fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), std::io::Error>> {
-        #[project]
-        match self.project() {
+        match self.get_mut() {
             Stream::Plain(ref mut s) => Pin::new(s).poll_close(cx),
             Stream::Tls(ref mut s) => Pin::new(s).poll_close(cx),
         }