fix: Remove Pin API related unsafe code

Author: k-nasa

src/stream/stream/timeout.rs

@@ -4,22 +4,24 @@ use std::pin::Pin;
 use std::time::Duration;
 
 use futures_timer::Delay;
+use pin_project_lite::pin_project;
 
 use crate::future::Future;
 use crate::stream::Stream;
 use crate::task::{Context, Poll};
 
-/// A stream with timeout time set
-#[derive(Debug)]
-pub struct Timeout<S: Stream> {
-    stream: S,
-    delay: Delay,
+pin_project! {
+    /// A stream with timeout time set
+    #[derive(Debug)]
+    pub struct Timeout<S: Stream> {
+        #[pin]
+        stream: S,
+        #[pin]
+        delay: Delay,
+    }
 }
 
 impl<S: Stream> Timeout<S> {
-    pin_utils::unsafe_pinned!(stream: S);
-    pin_utils::unsafe_pinned!(delay: Delay);
-
     pub fn new(stream: S, dur: Duration) -> Timeout<S> {
         let delay = Delay::new(dur);
 
@@ -30,11 +32,13 @@ impl<S: Stream> Timeout<S> {
 impl<S: Stream> Stream for Timeout<S> {
     type Item = Result<S::Item, TimeoutError>;
 
-    fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
-        match self.as_mut().stream().poll_next(cx) {
+    fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
+        let this = self.project();
+
+        match this.stream.poll_next(cx) {
             Poll::Ready(Some(v)) => Poll::Ready(Some(Ok(v))),
             Poll::Ready(None) => Poll::Ready(None),
-            Poll::Pending => match self.delay().poll(cx) {
+            Poll::Pending => match this.delay.poll(cx) {
                 Poll::Ready(_) => Poll::Ready(Some(Err(TimeoutError { _private: () }))),
                 Poll::Pending => Poll::Pending,
             },