Detect if currently editing a comment

[lougreenwood]

Maybe this isn't the correct place to ask since it's not strictly comment related, but it is tangential.

I'm trying to build an autocmd to change the textwidth when editing a comment. The reason is that the code base I work on is Javascript and uses Prettier to format it's code with a line length of 120. With Prettier this isn't a strict rule, but a guideline so lines are often more or less than 120. This is all inherited from the editor config.

However, for comments, 120 is too long, so I want to dynamically change the textwidth value when editing a comment, my idea is to use an autocmd and somehow detect if the current line is a comment (and then update textwidth).

So, my question is, can anyone give tips on how to detect if the current line is a comment? I skimmed through the API for Comment.nvim, but I didn't see any utils for this.