Fix 1.57 clippy warnings

Author: paolobarbolini

src/buf/buf_mut.rs

@@ -3,7 +3,7 @@ use crate::buf::{limit, Chain, Limit, UninitSlice};
 use crate::buf::{writer, Writer};
 use crate::{panic_advance, panic_does_not_fit, TryGetError};
 
-use core::{mem, ptr, usize};
+use core::{mem, ptr};
 
 use alloc::{boxed::Box, vec::Vec};
 
@@ -1503,7 +1503,7 @@ unsafe impl BufMut for &mut [u8] {
         }
 
         // Lifetime dance taken from `impl Write for &mut [u8]`.
-        let (_, b) = core::mem::replace(self, &mut []).split_at_mut(cnt);
+        let (_, b) = core::mem::take(self).split_at_mut(cnt);
         *self = b;
     }
 
@@ -1559,7 +1559,7 @@ unsafe impl BufMut for &mut [core::mem::MaybeUninit<u8>] {
         }
 
         // Lifetime dance taken from `impl Write for &mut [u8]`.
-        let (_, b) = core::mem::replace(self, &mut []).split_at_mut(cnt);
+        let (_, b) = core::mem::take(self).split_at_mut(cnt);
         *self = b;
     }
 
@@ -1600,7 +1600,7 @@ unsafe impl BufMut for Vec<u8> {
     #[inline]
     fn remaining_mut(&self) -> usize {
         // A vector can never have more than isize::MAX bytes
-        core::isize::MAX as usize - self.len()
+        isize::MAX as usize - self.len()
     }
 
     #[inline]

src/bytes.rs

@@ -2,7 +2,7 @@ use core::iter::FromIterator;
 use core::mem::{self, ManuallyDrop};
 use core::ops::{Deref, RangeBounds};
 use core::ptr::NonNull;
-use core::{cmp, fmt, hash, ptr, slice, usize};
+use core::{cmp, fmt, hash, ptr, slice};
 
 use alloc::{
     alloc::{dealloc, Layout},

src/bytes_mut.rs

@@ -2,7 +2,7 @@ use core::iter::FromIterator;
 use core::mem::{self, ManuallyDrop, MaybeUninit};
 use core::ops::{Deref, DerefMut};
 use core::ptr::{self, NonNull};
-use core::{cmp, fmt, hash, isize, slice, usize};
+use core::{cmp, fmt, hash, slice};
 
 use alloc::{
     borrow::{Borrow, BorrowMut},
@@ -1722,7 +1722,7 @@ impl From<BytesMut> for Vec<u8> {
             let shared = bytes.data as *mut Shared;
 
             if unsafe { (*shared).is_unique() } {
-                let vec = mem::replace(unsafe { &mut (*shared).vec }, Vec::new());
+                let vec = core::mem::take(unsafe { &mut (*shared).vec });
 
                 unsafe { release_shared(shared) };
 
@@ -1797,7 +1797,7 @@ unsafe fn shared_v_to_vec(data: &AtomicPtr<()>, ptr: *const u8, len: usize) -> V
         let shared = &mut *shared;
 
         // Drop shared
-        let mut vec = mem::replace(&mut shared.vec, Vec::new());
+        let mut vec = core::mem::take(&mut shared.vec);
         release_shared(shared);
 
         // Copy back buffer

tests/test_buf_mut.rs

@@ -4,7 +4,6 @@ use bytes::buf::UninitSlice;
 use bytes::{BufMut, BytesMut};
 use core::fmt::Write;
 use core::mem::MaybeUninit;
-use core::usize;
 
 #[test]
 fn test_vec_as_mut_buf() {

tests/test_bytes.rs

@@ -5,7 +5,6 @@ use std::sync::atomic::{AtomicUsize, Ordering};
 use std::sync::Arc;
 
 use std::panic::{self, AssertUnwindSafe};
-use std::usize;
 
 const LONG: &[u8] = b"mary had a little lamb, little lamb, little lamb";
 const SHORT: &[u8] = b"hello world";