Refactor LocalWaker (#224)

actix-utils/src/dispatcher.rs

@@ -290,10 +290,8 @@ where
                 }
                 State::Error(_) => {
                     // flush write buffer
-                    if !this.framed.is_write_buf_empty() {
-                        if let Poll::Pending = this.framed.flush(cx) {
-                            return Poll::Pending;
-                        }
+                    if !this.framed.is_write_buf_empty() && this.framed.flush(cx).is_pending() {
+                        return Poll::Pending;
                     }
                     Poll::Ready(Err(this.state.take_error()))
                 }

actix-utils/src/inflight.rs

@@ -74,7 +74,7 @@ where
     type Future = InFlightServiceResponse<T>;
 
     fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
-        if let Poll::Pending = self.service.poll_ready(cx)? {
+        if self.service.poll_ready(cx)?.is_pending() {
             Poll::Pending
         } else if !self.count.available(cx) {
             log::trace!("InFlight limit exceeded");

actix-utils/src/order.rs

@@ -160,7 +160,12 @@ where
         }
 
         // check nested service
-        if let Poll::Pending = self.service.poll_ready(cx).map_err(InOrderError::Service)? {
+        if self
+            .service
+            .poll_ready(cx)
+            .map_err(InOrderError::Service)?
+            .is_pending()
+        {
             Poll::Pending
         } else {
             Poll::Ready(Ok(()))

actix-utils/src/task.rs

@@ -19,6 +19,7 @@ use std::{fmt, rc};
 ///
 /// A single `AtomicWaker` may be reused for any number of calls to `register` or
 /// `wake`.
+// TODO: Refactor to Cell when remove deprecated methods (@botika)
 #[derive(Default)]
 pub struct LocalWaker {
     pub(crate) waker: UnsafeCell<Option<Waker>>,
@@ -34,6 +35,10 @@ impl LocalWaker {
         }
     }
 
+    #[deprecated(
+        since = "2.1.0",
+        note = "In favor of `wake`. State of the register doesn't matter at `wake` up"
+    )]
     #[inline]
     /// Check if waker has been registered.
     pub fn is_registered(&self) -> bool {
@@ -47,9 +52,8 @@ impl LocalWaker {
     pub fn register(&self, waker: &Waker) -> bool {
         unsafe {
             let w = self.waker.get();
-            let is_registered = (*w).is_some();
-            *w = Some(waker.clone());
-            is_registered
+            let last_waker = w.replace(Some(waker.clone()));
+            last_waker.is_some()
         }
     }
 
@@ -63,6 +67,7 @@ impl LocalWaker {
         }
     }
 
+    #[inline]
     /// Returns the last `Waker` passed to `register`, so that the user can wake it.
     ///
     /// If a waker has not been registered, this returns `None`.