chore: remove dependency to pin-utils (#2929)

Signed-off-by: tison <[email protected]>

Author: tisonkun

futures-util/Cargo.toml

@@ -41,7 +41,6 @@ slab = { version = "0.4.2", default-features = false, optional = true }
 memchr = { version = "2.2", optional = true }
 futures_01 = { version = "0.1.25", optional = true, package = "futures" }
 tokio-io = { version = "0.1.9", optional = true }
-pin-utils = "0.1.0"
 pin-project-lite = "0.2.6"
 spin = { version = "0.9.8", optional = true }
 

futures-util/src/future/future/mod.rs

@@ -10,6 +10,7 @@ use core::pin::Pin;
 
 use crate::fns::{inspect_fn, into_fn, ok_fn, InspectFn, IntoFn, OkFn};
 use crate::future::{assert_future, Either};
+use crate::pin_mut;
 use crate::stream::assert_stream;
 #[cfg(feature = "alloc")]
 use futures_core::future::{BoxFuture, LocalBoxFuture};
@@ -18,7 +19,6 @@ use futures_core::{
     stream::Stream,
     task::{Context, Poll},
 };
-use pin_utils::pin_mut;
 
 // Combinators
 

futures-util/src/lib.rs

@@ -23,7 +23,6 @@ extern crate std;
 
 // Macro re-exports
 pub use futures_core::ready;
-pub use pin_utils::pin_mut;
 
 #[cfg(feature = "async-await")]
 #[macro_use]
@@ -33,7 +32,6 @@ mod async_await;
 pub use self::async_await::*;
 
 // Not public API.
-#[cfg(feature = "async-await")]
 #[doc(hidden)]
 pub mod __private {
     pub use crate::*;
@@ -43,6 +41,7 @@ pub mod __private {
         result::Result::{Err, Ok},
     };
 
+    #[cfg(feature = "async-await")]
     pub mod async_await {
         pub use crate::async_await::*;
     }
@@ -328,4 +327,5 @@ pub mod lock;
 mod abortable;
 
 mod fns;
+mod macros;
 mod unfold_state;

futures-util/src/macros.rs

@@ -0,0 +1,31 @@
+/// Pins a value on the stack.
+///
+/// Can safely pin values that are not `Unpin` by taking ownership.
+///
+/// **Note:** Since Rust 1.68, this macro is soft-deprecated in favor of
+/// [`pin!`](https://doc.rust-lang.org/std/pin/macro.pin.html) macro
+/// in the standard library.
+///
+/// # Example
+///
+/// ```rust
+/// # use futures_util::pin_mut;
+/// # use core::pin::Pin;
+/// # struct Foo {}
+/// let foo = Foo { /* ... */ };
+/// pin_mut!(foo);
+/// let _: Pin<&mut Foo> = foo;
+/// ```
+#[macro_export]
+macro_rules! pin_mut {
+    ($($x:ident),* $(,)?) => { $(
+        // Move the value to ensure that it is owned
+        let mut $x = $x;
+        // Shadow the original binding so that it can't be directly accessed
+        // ever again.
+        #[allow(unused_mut)]
+        let mut $x = unsafe {
+            $crate::__private::Pin::new_unchecked(&mut $x)
+        };
+    )* }
+}