[Distutils] PEP 517 - specifying build system in pyproject.toml

[Nick Coghlan]

On 20 May 2017 at 00:18, Thomas Kluyver <thomas at kluyver.me.uk> wrote:
> Hi,
>
> I'd like to make another push for PEP 517, which would make it possible
> to build wheels from a source tree with other build tools, without
> needing setup.py.
>
> https://www.python.org/dev/peps/pep-0517/
>
> Last time this was discussed we made a couple of minor changes to the
> PEP, but we didn't want to accept another packaging related PEP until
> PEP 518 was implemented in pip. I'm pleased to say that that
> implementation has just been merged:
> https://github.com/pypa/pip/pull/4144 .

Huzzah, and congratulations! :)

Regarding the encoding question, I agree with your recommendation with
one key amendment to account for the 16-bit console APIs on Windows:

* on platforms with 8-bit standard streams (e.g. Linux, Mac OS X),
build systems SHOULD emit UTF-8 encoded output
* on platforms with 16-bit standard streams (e.g. Windows), build
systems SHOULD emit UTF-16-LE encoded output
* on platforms that offer both, build systems SHOULD use the 16-bit
streams to match the default behaviour of CPython 3.6+
* install tools MUST NOT fail the build solely due to improperly
encoded output, but are otherwise free to handle the situation as they
see fit

Folks on Python 3.5 and earlier on Windows may still have problems
given that guidance (since that uses the 8-bit stream interfaces with
the Windows native encodings by default), but that's also a large part
of why CPython's behaviour on Windows was changed in 3.6 :)

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia