`mem_replace_with_default` wrongly unmangles macros

[profetia]

Summary

mem_replace_with_default wrongly unmangles macros when giving suggestions.

Reproducer

I tried this code:

fn dest_from_macro() {
    macro_rules! borrow_mut {
        ($x:expr) => {
            &mut $x
        };
    }

    let mut text = String::from("foo");
    let replaced = std::mem::replace(borrow_mut!(text), String::default());
}

I expected to see this happen:

LL |     let replaced = std::mem::replace(borrow_mut!(text), String::default());
   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(borrow_mut!(text))`

Instead, this happened:

LL |     let replaced = std::mem::replace(borrow_mut!(text), String::default());
   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `std::mem::take(&mut $x)`

Version

rustc 1.92.0-nightly (4645a7988 2025-09-17)
binary: rustc
commit-hash: 4645a7988177c286f61609cc667ecae4c571a2e8
commit-date: 2025-09-17
host: x86_64-unknown-linux-gnu
release: 1.92.0-nightly
LLVM version: 21.1.1

Additional Labels

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