[PATCH stable] hghave: make black version regex work with newer versions of black

[Yuya Nishihara]

On Sun, 22 May 2022 02:43:05 +0200, Joerg Sonnenberger wrote:
> Am Sun, May 22, 2022 at 02:13:03AM +0200 schrieb Manuel Jacob:
> > # HG changeset patch
> > # User Manuel Jacob <me at manueljacob.de>
> > # Date 1653176900 -7200
> > #      Sun May 22 01:48:20 2022 +0200
> > # Branch stable
> > # Node ID 29f2716c5c54c7e0f7aa6d91979893f5d2078862
> > # Parent  477b5145e1a02715f846ce017b460858a58e03b1
> > # EXP-Topic black_version_regex
> > hghave: make black version regex work with newer versions of black

This works for me, but I hesitated to queue since test-check-format.t starts
detecting formatting errors with

  % black --version
  black, 22.3.0 (compiled: no)

> > Black commit 117891878e5be4d6b771ae5de299e51b679cea27 (included in black >=
> > 21.11b0) dropped the string "version " from the output of "black --version". To
> > make the regex work with newer black versions, make matching of "version "
> > optional.  
> 
> I had a patch like this locally, but newer black versions insist on
> incompatible output and that's where I stopped. There is also the issue
> that the regex itself seems wrong, e.g. the unescaped "." in the [].

[.] should be okay. "." has no special meaning in character set.