Issue6246-Let statement should rewrite rhs with comments after equal sign

[johnhuichen]

Pull Request Template

Checklist

• Confirmed that cargo test passes

Related Issues/PRs

#6246

Changes

The problem in 6246

fn main() {
    let foo = 
    // 114514
    if true {
        1919
    } else {
        810
    };
}

Rustfmt doesn't seem to account for comments between the = sign and the if expression. I solve it by checking the existence of a comment span and insert it back after rewrite.

Testing

added a test case tests/source/issue-6246.rs

[ytmimi]

Haven't had a chance to review this yet (and likely won't for a while), but I wanted to point out that #5501 is already open to address the same issue. Didn't catch that until recently. This one is much simpler, but it might not be accounting for multi-line comments or block comments.

[johnhuichen]

Closing my PR as https://github.com/rust-lang/rustfmt/pull/5501/files is addressing the same issue