From 2dde8820fa2b108db011166467f20cabb4627b69 Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Fri, 11 Mar 2022 12:27:23 +1100
Subject: [PATCH] Remove what's left of the first trait in `extension_trait`.

---
 src/future/future/mod.rs | 4 +---
 src/io/buf_read/mod.rs   | 4 +---
 src/io/read/mod.rs       | 4 +---
 src/io/seek/mod.rs       | 4 +---
 src/io/write/mod.rs      | 4 +---
 src/stream/stream/mod.rs | 4 +---
 src/utils.rs             | 8 +-------
 7 files changed, 7 insertions(+), 25 deletions(-)

diff --git a/src/future/future/mod.rs b/src/future/future/mod.rs
index d6c4d7e0..e20f8bac 100644
--- a/src/future/future/mod.rs
+++ b/src/future/future/mod.rs
@@ -23,14 +23,12 @@ cfg_unstable_default! {
 pub use core::future::Future as Future;
 
 extension_trait! {
-    pub trait Future {}
-
     #[doc = r#"
         Extension methods for [`Future`].
 
         [`Future`]: ../future/trait.Future.html
     "#]
-    pub trait FutureExt: core::future::Future {
+    pub trait FutureExt: Future {
         /// Returns a Future that delays execution for a specified time.
         ///
         /// # Examples
diff --git a/src/io/buf_read/mod.rs b/src/io/buf_read/mod.rs
index 82917156..8f248e2b 100644
--- a/src/io/buf_read/mod.rs
+++ b/src/io/buf_read/mod.rs
@@ -18,14 +18,12 @@ use crate::task::{Context, Poll};
 pub use futures_io::AsyncBufRead as BufRead;
 
 extension_trait! {
-    pub trait BufRead {}
-
     #[doc = r#"
         Extension methods for [`BufRead`].
 
         [`BufRead`]: ../trait.BufRead.html
     "#]
-    pub trait BufReadExt: futures_io::AsyncBufRead {
+    pub trait BufReadExt: BufRead {
         #[doc = r#"
             Reads all bytes into `buf` until the delimiter `byte` or EOF is reached.
 
diff --git a/src/io/read/mod.rs b/src/io/read/mod.rs
index b8855886..f96b8154 100644
--- a/src/io/read/mod.rs
+++ b/src/io/read/mod.rs
@@ -24,14 +24,12 @@ pub use take::Take;
 pub use futures_io::AsyncRead as Read;
 
 extension_trait! {
-    pub trait Read {}
-
     #[doc = r#"
         Extension methods for [`Read`].
 
         [`Read`]: ../trait.Read.html
     "#]
-    pub trait ReadExt: futures_io::AsyncRead {
+    pub trait ReadExt: Read {
         #[doc = r#"
             Reads some bytes from the byte stream.
 
diff --git a/src/io/seek/mod.rs b/src/io/seek/mod.rs
index cafbfe62..af7cafcf 100644
--- a/src/io/seek/mod.rs
+++ b/src/io/seek/mod.rs
@@ -7,14 +7,12 @@ use crate::io::SeekFrom;
 pub use futures_io::AsyncSeek as Seek;
 
 extension_trait! {
-    pub trait Seek {}
-
     #[doc = r#"
         Extension methods for [`Seek`].
 
         [`Seek`]: ../trait.Seek.html
     "#]
-    pub trait SeekExt: futures_io::AsyncSeek {
+    pub trait SeekExt: Seek {
         #[doc = r#"
             Seeks to a new position in a byte stream.
 
diff --git a/src/io/write/mod.rs b/src/io/write/mod.rs
index 6e9a574f..b18d80f0 100644
--- a/src/io/write/mod.rs
+++ b/src/io/write/mod.rs
@@ -15,14 +15,12 @@ use crate::io::{self, IoSlice};
 pub use futures_io::AsyncWrite as Write;
 
 extension_trait! {
-    pub trait Write {}
-
     #[doc = r#"
         Extension methods for [`Write`].
 
         [`Write`]: ../trait.Write.html
     "#]
-    pub trait WriteExt: futures_io::AsyncWrite {
+    pub trait WriteExt: Write {
         #[doc = r#"
             Writes some bytes into the byte stream.
 
diff --git a/src/stream/stream/mod.rs b/src/stream/stream/mod.rs
index 48fdbb22..0ead0800 100644
--- a/src/stream/stream/mod.rs
+++ b/src/stream/stream/mod.rs
@@ -146,14 +146,12 @@ cfg_unstable! {
 pub use futures_core::stream::Stream as Stream;
 
 extension_trait! {
-    pub trait Stream {}
-
     #[doc = r#"
         Extension methods for [`Stream`].
 
         [`Stream`]: ../stream/trait.Stream.html
     "#]
-    pub trait StreamExt: futures_core::stream::Stream {
+    pub trait StreamExt: Stream {
         #[doc = r#"
             Advances the stream and returns the next value.
 
diff --git a/src/utils.rs b/src/utils.rs
index d662e17f..96f24fd2 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -246,14 +246,8 @@ macro_rules! cfg_default {
 #[doc(hidden)]
 macro_rules! extension_trait {
     (
-        // Interesting patterns:
-        // - `$name`: trait name that gets rendered in the docs
-        // - `$ext`: name of the hidden extension trait
-        // - `$base`: base trait
-        pub trait $name:ident {}
-
         #[doc = $doc_ext:tt]
-        pub trait $ext:ident: $base:path {
+        pub trait $ext:ident: $name:ident {
             $($body_ext:tt)*
         }
     ) => {