net: use std::future::ready instead of own Ready future (#4271)

tokio/src/future/mod.rs

@@ -8,11 +8,6 @@ pub(crate) mod maybe_done;
 mod poll_fn;
 pub use poll_fn::poll_fn;
 
-cfg_not_loom! {
-    mod ready;
-    pub(crate) use ready::{ok, Ready};
-}
-
 cfg_process! {
     mod try_join;
     pub(crate) use try_join::try_join3;

tokio/src/future/ready.rs

@@ -1,27 +0,0 @@
-use std::future::Future;
-use std::pin::Pin;
-use std::task::{Context, Poll};
-
-/// Future for the [`ok`](ok()) function.
-///
-/// `pub` in order to use the future as an associated type in a sealed trait.
-#[derive(Debug)]
-// Used as an associated type in a "sealed" trait.
-#[allow(unreachable_pub)]
-pub struct Ready<T>(Option<T>);
-
-impl<T> Unpin for Ready<T> {}
-
-impl<T> Future for Ready<T> {
-    type Output = T;
-
-    #[inline]
-    fn poll(mut self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<T> {
-        Poll::Ready(self.0.take().unwrap())
-    }
-}
-
-/// Creates a future that is immediately ready with a success value.
-pub(crate) fn ok<T, E>(t: T) -> Ready<Result<T, E>> {
-    Ready(Some(Ok(t)))
-}

tokio/src/net/addr.rs

@@ -1,5 +1,4 @@
-use crate::future;
-
+use std::future;
 use std::io;
 use std::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6};
 
@@ -56,7 +55,7 @@ impl sealed::ToSocketAddrsPriv for SocketAddr {
 
     fn to_socket_addrs(&self, _: sealed::Internal) -> Self::Future {
         let iter = Some(*self).into_iter();
-        future::ok(iter)
+        future::ready(Ok(iter))
     }
 }
 
@@ -96,7 +95,7 @@ impl sealed::ToSocketAddrsPriv for (IpAddr, u16) {
 
     fn to_socket_addrs(&self, _: sealed::Internal) -> Self::Future {
         let iter = Some(SocketAddr::from(*self)).into_iter();
-        future::ok(iter)
+        future::ready(Ok(iter))
     }
 }
 
@@ -138,7 +137,7 @@ impl sealed::ToSocketAddrsPriv for &[SocketAddr] {
 
     fn to_socket_addrs(&self, _: sealed::Internal) -> Self::Future {
         let iter = self.to_vec().into_iter();
-        future::ok(iter)
+        future::ready(Ok(iter))
     }
 }