Comment by pornel

I've looked at the code from the PR. It seems to use safe types and standard idioms like pattern matching, so at least at first glance it looks like Rust.

It could have been worse. C++ code naively converted line-by-line to Rust typically results in weird and unsafe Rust, but in this case it seems they've only been strict about the results being the same, not the structure of the implementation.

Rewrites have a very high risk of introducing regressions. Trying to fix bugs while rewriting will only make things harder, because instead of simply comparing outputs exactly, you'll have to judge which output is the right one. If you let the behavior significantly diverge during the rewrite, you'll just have two differently buggy codebases and no reference to follow.

It's much easier to make a bug-for-bug compatible copy, and fix bugs later.