`std_instead_of_core` and similar lints are not helpful on a nested `std` import

[cyrgani]

Summary

std_instead_of_core, std_instead_of_alloc, alloc_instead_of_core do not explain which items in a larger nested import can be imported from elsewhere and which cannot, causing impractical warnings.

Reproducer

I tried this code:

use std::{
    alloc::{self, Layout},
    marker::PhantomData,
    ops::Deref,
    sync::{
        Mutex,
        atomic::{AtomicUsize, Ordering},
    },
    thread::{self, JoinHandle, sleep},
    time::Duration,
};

I expected to see this happen:
individual warnings for each item that can come from core or alloc

Instead, this happened:

warning: used import from `std` instead of `core`
  --> src/lib.rs:15:5
   |
15 | use std::{
   |     ^^^ help: consider importing the item from `core`: `core`
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#std_instead_of_core
   = note: `#[warn(clippy::std_instead_of_core)]` implied by `#[warn(clippy::restriction)]`

warning: used import from `std` instead of `core`
  --> src/lib.rs:15:5
   |
15 | use std::{
   |     ^^^ help: consider importing the item from `core`: `core`
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#std_instead_of_core

Version

rustc 1.89.0-nightly (d13a431a6 2025-06-09)
binary: rustc
commit-hash: d13a431a6cc69cd65efe7c3eb7808251d6fd7a46
commit-date: 2025-06-09
host: x86_64-unknown-linux-gnu
release: 1.89.0-nightly
LLVM version: 20.1.5

Additional Labels

No response

[profetia]

This should already be fixed in #15016. Now it only lints when all the items in this large nested import can be imported from elsewhere

[blyxyas]

This is fixed in the latest master =^w^= the fix will arrive soon.