`implicit_haser` wrongly unmangled macros

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Summary

implicit_haser wrongly unmangled macros

Reproducer

Code:

use std::collections::HashMap;
use std::hash::Hash;

pub trait Foo<T>: Sized {
    fn make() -> (Self, Self);
}

impl<K: Hash + Eq, V> Foo<u64> for HashMap<K, V> {
    fn make() -> (Self, Self) {
        macro_rules! times_by_ten {
            ($num:expr) => {
                $num * 10
            };
        }

        (HashMap::new(), HashMap::with_capacity(times_by_ten!(5)))
    }
}

Current output:

warning: impl for `HashMap` should be generalized over different hashers
  --> src/main.rs:11:36
   |
11 | impl<K: Hash + Eq, V> Foo<u64> for HashMap<K, V> {
   |                                    ^^^^^^^^^^^^^
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#implicit_hasher
note: the lint level is defined here
  --> src/main.rs:2:9
   |
 2 | #![warn(clippy::implicit_hasher)]
   |         ^^^^^^^^^^^^^^^^^^^^^^^
help: add a type parameter for `BuildHasher`
   |
11 ~ impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<u64> for HashMap<K, V, S> {
12 |     fn make() -> (Self, Self) {
...
18 |
19 ~         (HashMap::default(), HashMap::with_capacity_and_hasher($num * 10, Default::default()))
   |

Desired output:

warning: impl for `HashMap` should be generalized over different hashers
  --> src/main.rs:11:36
   |
11 | impl<K: Hash + Eq, V> Foo<u64> for HashMap<K, V> {
   |                                    ^^^^^^^^^^^^^
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#implicit_hasher
note: the lint level is defined here
  --> src/main.rs:2:9
   |
 2 | #![warn(clippy::implicit_hasher)]
   |         ^^^^^^^^^^^^^^^^^^^^^^^
help: add a type parameter for `BuildHasher`
   |
11 ~ impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<u64> for HashMap<K, V, S> {
12 |     fn make() -> (Self, Self) {
...
18 |
19 ~         (HashMap::default(), HashMap::with_capacity_and_hasher(times_by_ten!(5), Default::default()))
   |

Version

rustc 1.93.0-nightly (2286e5d22 2025-11-13)
binary: rustc
commit-hash: 2286e5d224b3413484cf4f398a9f078487e7b49d
commit-date: 2025-11-13
host: x86_64-unknown-linux-gnu
release: 1.93.0-nightly
LLVM version: 21.1.5

Additional Labels

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