`single_range_in_vec_init` wrongly unmangles macros

[profetia]

Summary

single_range_in_vec_init wrongly unmangles macros in the range expression

Reproducer

I tried this code:

    macro_rules! as_i32 {
        ($x:expr) => {
            $x as i32
        };
    }

    let input = vec![0..as_i32!(10)];

I expected to see this happen:

help: if you wanted a `Vec` that contains the entire range, try
   |
12 -     let input = vec![0..as_i32!(10)];
12 +     let input = (0..as_i32!(10)).collect::<std::vec::Vec<i32>>();

Instead, this happened:

help: if you wanted a `Vec` that contains the entire range, try
   |
12 -     let input = vec![0..as_i32!(10)];
12 +     let input = (0..$x as i32).collect::<std::vec::Vec<i32>>();

Version

rustc 1.93.0-nightly (d5419f1e9 2025-10-30)
binary: rustc
commit-hash: d5419f1e97b90741d51841f800d3c697c662567d
commit-date: 2025-10-30
host: x86_64-unknown-linux-gnu
release: 1.93.0-nightly
LLVM version: 21.1.3

Additional Labels

No response

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