I don't have an objection to enforcing sembr but the implementation does look fragile, e.g. there's no tokenizer. Have you considered using an existing tool like https://github.com/bobheadxi/readable?

I have not... thanks for the suggestion, will have a look.

I have tried using readable to have a GitHub action that runs check, and format all the existing code, but the tool is immature, it gave errors for some files saying Cannot take length of multi-line node '[object Object]' (bobheadxi/readable#18) and for others the aforementioned issue is there, it does the wrong thing when it encounters e.g.(bobheadxi/readable#17). I am not sure what should be done here, make readable better or create another tool?

This tool of mine handles both issues without choking. I intend to get back to making it more fancy... I keep postponing.

Sorry, due to me messing up a git operation, we sadly had to force-push the whole commit history of rustc-dev-guide :( If you'd like to update this pull request, you will have to rebase it in a special way onto the new commit history (the new master):

git fetch origin --all
git checkout <pr-branch>
git rebase --onto origin/master origin/master-old
git push --force-with-lease

More context can be found here.

Thanks for the PR. If you have write access, feel free to merge this PR if it does not need reviews. You can request a review using r? rustc-dev-guide or r? <username>.

I don't know how to do tokenization, but I attached a sample chapter to show output from the tool