write_literal breaks raw strings

[ChrisJefferson]

Summary

write_literal doesn't correctly handle raw strings.

Reproducer

I tried this code:

writeln!(
                pre,
                "{}",
                r#"
$#CON colcheck "Use the sum of col {{index[0]}} for {{index[1]}}"
find colcheck: matrix indexed by [int(1..width), ALLRANGE] of bool"#
                "
            )?;

I expected write_literal to rewrite this to valid Rust. Instead, this happened:

writeln!(
                pre,
                "
$#CON colcheck \\"Use the sum of col {{{{index[0]}}}} for {{{{index[1]}}}}\\"
find colcheck: matrix indexed by [int(1..width), ALLRANGE] of bool"
            )?;

My preference would be to just leave the raw string as is, I can't see why that wouldn't be the easist, and least-suprising option.

Version

rustc 1.83.0 (90b35a623 2024-11-26)
binary: rustc
commit-hash: 90b35a6239c3d8bdabc530a6a0816f7ff89a0aaf
commit-date: 2024-11-26
host: x86_64-unknown-linux-gnu
release: 1.83.0
LLVM version: 19.1.1

Additional Labels

No response