Switch std::vec::PeekMut::pop from self to this parameter.

Since PeekMut implements Deref, it shouldn't have any methods of its
own.

See also: `std::collections::binary_heap::PeekMut::pop`

.mailmap

@@ -609,6 +609,7 @@ Shohei Wada <pc@wada314.jp>
 Shotaro Yamada <sinkuu@sinkuu.xyz>
 Shotaro Yamada <sinkuu@sinkuu.xyz> <sinkuu@users.noreply.github.com>
 Shyam Sundar B <shyambaskaran@outlook.com>
+Sidney Cammeresi <sac@cheesecake.org> <sac@readyset.io>
 Simon Barber-Dueck <sbarberdueck@gmail.com> Simon BD <simon@server>
 Simon Sapin <simon@exyr.org> <simon.sapin@exyr.org>
 Simonas Kazlauskas <git@kazlauskas.me> Simonas Kazlauskas <github@kazlauskas.me>

library/alloc/src/vec/peek_mut.rs

@@ -29,9 +29,9 @@ impl<'a, T> PeekMut<'a, T> {
 
     /// Removes the peeked value from the vector and returns it.
     #[unstable(feature = "vec_peek_mut", issue = "122742")]
-    pub fn pop(self) -> T {
+    pub fn pop(this: Self) -> T {
         // SAFETY: PeekMut is only constructed if the vec is non-empty
-        unsafe { self.vec.pop().unwrap_unchecked() }
+        unsafe { this.vec.pop().unwrap_unchecked() }
     }
 }
 

library/alloctests/tests/vec.rs

@@ -15,7 +15,7 @@ use std::ops::Bound::*;
 use std::panic::{AssertUnwindSafe, catch_unwind};
 use std::rc::Rc;
 use std::sync::atomic::{AtomicU32, Ordering};
-use std::vec::{Drain, IntoIter};
+use std::vec::{Drain, IntoIter, PeekMut};
 
 use crate::testing::macros::struct_with_counted_drop;
 
@@ -2647,7 +2647,7 @@ fn test_peek_mut() {
         assert_eq!(*p, 2);
         *p = 0;
         assert_eq!(*p, 0);
-        p.pop();
+        PeekMut::pop(p);
         assert_eq!(vec.len(), 1);
     } else {
         unreachable!()