stream: add `next` and `map` utility fn (#1962)

Introduces `StreamExt` trait. This trait will be used to add utility functions
to make working with streams easier. This patch includes two functions:

* `next`: a future returning the item in the stream.
* `map`: transform each item in the stream.

2 files changed, 2 insertions, 3 deletions

diff --git a/tokio/src/net/unix/incoming.rs b/tokio/src/net/unix/incoming.rs
index dbe964a8..bede96dd 100644
--- a/tokio/src/net/unix/incoming.rs
+++ b/tokio/src/net/unix/incoming.rs
@@ -27,7 +27,7 @@ impl Incoming<'_> {
 }
 
 #[cfg(feature = "stream")]
-impl futures_core::Stream for Incoming<'_> {
+impl crate::stream::Stream for Incoming<'_> {
     type Item = io::Result<UnixStream>;
 
     fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
diff --git a/tokio/src/net/unix/listener.rs b/tokio/src/net/unix/listener.rs
index 311bae2c..4b93bf82 100644
--- a/tokio/src/net/unix/listener.rs
+++ b/tokio/src/net/unix/listener.rs
@@ -104,8 +104,7 @@ impl UnixListener {
     ///
     /// ```no_run
     /// use tokio::net::UnixListener;
-    ///
-    /// use futures::StreamExt;
+    /// use tokio::stream::StreamExt;
     ///
     /// #[tokio::main]
     /// async fn main() {