On 28 July 2017 at 15:39, Robert Collins <robe...@robertcollins.net> wrote: > On 28 July 2017 at 15:34, Nick Coghlan <ncogh...@gmail.com> wrote: >> Clarifying to add: I think this is a worthwhile change, as it helps to >> ensure that the static config files actually *are* static, and hence >> less dependent on being read specifically with Python's configparser >> library. That's a boon for interoperability, even if it means that >> folks that genuinely want interpolation will need to switch to a >> "setup.cfg.in" style approach where they use the templating tool of >> their choice to read in the input file, substitute values, and then >> write out a completely static setup.cfg file. > > Yeah, I'm going to disagree here. While its true that using > interpolation binds the config file semantic interpretation to Python, > its *already* bound that way due to the idiosyncratic continuations > style and nested sections. > > Doing a .in -> actual-foo is a great pattern for build systems > building expensive artifacts with complex dependency chains. Not > problems have, and copying their solutions without the problem is just > unnecessary, and unhelpful, complexity. > > +1 from me for retaining interpolation.
Fair point, and reading the original bug report in https://bugs.python.org/issue20754, it seems the main problems were that: - it wasn't documented that interpolation is enabled when parsing setup.cfg - the Python 2.7 implementation currently uses ConfigParser rather than SafeConfigParser, so escaping with `%%` didn't work in 2.x That would make the following the lowest impact resolution that still fixes the original reported problem: - update the ConfigParser (3.x) and SafeConfigParser (2.x) docs to explicitly say that "%%" works as an escape - update setuptools and distutils to use SafeConfigParser in 2.7 - update the setuptools and distutils docs to say that interpolation is enabled when reading setup.cfg and "%%" works as an escape (except on older versions of Python 2.x with either distutils or an older version of setuptools). So I'll retract my initial response as being ill-informed (since I didn't click through and read the original bug report). Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia _______________________________________________ Distutils-SIG maillist - Distutils-SIG@python.org https://mail.python.org/mailman/listinfo/distutils-sig
