Rollup merge of #70777 - faern:use-assoc-int-consts2, r=dtolnay

Don't import integer and float modules, use assoc consts

Stop importing the standard library integer and float modules to reach the `MIN`, `MAX` and other constants. They are available directly on the primitive types now.

This PR is a follow up of #69860 which made sure we use the new constants in documentation.

This type of change touches a lot of files, and previously all my assoc int consts PRs had collisions and were accepted only after a long delay. So I'd prefer to do it in smaller steps now. Just removing these imports seem like a good next step.

r? @dtolnay

Author: Dylan-DPC

src/etc/test-float-parse/u64-pow2.rs

@@ -1,7 +1,6 @@
 mod _common;
 
 use _common::validate;
-use std::u64;
 
 fn main() {
     for exp in 19..64 {

src/liballoc/alloc.rs

@@ -4,7 +4,6 @@
 
 use core::intrinsics::{self, min_align_of_val, size_of_val};
 use core::ptr::{NonNull, Unique};
-use core::usize;
 
 #[stable(feature = "alloc_module", since = "1.28.0")]
 #[doc(inline)]

src/liballoc/collections/binary_heap.rs

@@ -20,7 +20,6 @@
 //! ```
 //! use std::cmp::Ordering;
 //! use std::collections::BinaryHeap;
-//! use std::usize;
 //!
 //! #[derive(Copy, Clone, Eq, PartialEq)]
 //! struct State {

src/liballoc/rc.rs

@@ -250,7 +250,6 @@ use core::ops::{CoerceUnsized, Deref, DispatchFromDyn, Receiver};
 use core::pin::Pin;
 use core::ptr::{self, NonNull};
 use core::slice::{self, from_raw_parts_mut};
-use core::usize;
 
 use crate::alloc::{box_free, handle_alloc_error, AllocInit, AllocRef, Global, Layout};
 use crate::string::String;

src/liballoc/slice.rs

@@ -90,7 +90,6 @@ use core::borrow::{Borrow, BorrowMut};
 use core::cmp::Ordering::{self, Less};
 use core::mem::{self, size_of};
 use core::ptr;
-use core::{u16, u32, u8};
 
 use crate::borrow::ToOwned;
 use crate::boxed::Box;

src/liballoc/sync.rs

@@ -23,7 +23,6 @@ use core::ptr::{self, NonNull};
 use core::slice::{self, from_raw_parts_mut};
 use core::sync::atomic;
 use core::sync::atomic::Ordering::{Acquire, Relaxed, Release, SeqCst};
-use core::{isize, usize};
 
 use crate::alloc::{box_free, handle_alloc_error, AllocInit, AllocRef, Global, Layout};
 use crate::boxed::Box;

src/liballoc/tests.rs

@@ -3,8 +3,6 @@
 use core::any::Any;
 use core::clone::Clone;
 use core::convert::TryInto;
-use core::f64;
-use core::i64;
 use core::ops::Deref;
 use core::result::Result::{Err, Ok};
 

src/liballoc/tests/string.rs

@@ -1,7 +1,6 @@
 use std::borrow::Cow;
 use std::collections::TryReserveError::*;
 use std::mem::size_of;
-use std::{isize, usize};
 
 pub trait IntoCow<'a, B: ?Sized>
 where

src/liballoc/tests/vec.rs

@@ -3,7 +3,6 @@ use std::collections::TryReserveError::*;
 use std::mem::size_of;
 use std::panic::{catch_unwind, AssertUnwindSafe};
 use std::vec::{Drain, IntoIter};
-use std::{isize, usize};
 
 struct DropCounter<'a> {
     count: &'a mut u32,

src/liballoc/tests/vec_deque.rs

@@ -3,7 +3,6 @@ use std::collections::{vec_deque::Drain, VecDeque};
 use std::fmt::Debug;
 use std::mem::size_of;
 use std::panic::{catch_unwind, AssertUnwindSafe};
-use std::{isize, usize};
 
 use crate::hash;