Get parsed comments from pgn

[leszekhanusz]

I am now trying to create a Pyside6 widget which simulates the Analysis Board on lichess.

It's beginning to work but the comments displayed contain all the %csl %cal visual annotations (and others things like evals or clocks)

Since python-chess already contains the ARROWS_REGEX and other regexes, it would be nice if we could get the parsing done in this library to get the final comment to be displayed to the user.

[philipmk42]

I'd be happy to work on this. The building blocks are already in pgn.py (the per-annotation regexes for %clk, %emt, %eval, %csl, %cal), so the missing piece is an accessor that returns the comment with those stripped out.
Proposed API: a method on GameNode, for example clean_comment(), returning the node's comment text with all [%...] commands removed and surrounding whitespace collapsed. To also cover commands the library does not parse specifically (the issue mentions evals and clocks plus "other things"), I would strip any [%...] command generically rather than only the five known types. Example:
{ [%eval -0.5] [%clk 0:01:23] Black is slightly worse [%cal Rd1d4] } becomes Black is slightly worse.
Does that approach and naming work, or would you prefer a property, a different name, or stripping only the known annotation types? Happy to send a PR with tests and a changelog entry once you confirm the shape you would like.