[Distutils] PEP 517 again

[xoviat]

> The only reason I can think of that setuptools would need a dist_info
command would be to implement the PEP 517 prepare_wheel_metadata hook.

Yes. That is absolutely correct.

> But this hook is optional and in fact provides no value right now, so
it can't be a blocker for anything.

The simplest way to start on this issue is to replace egg_info in pip with
prepare_metadata_for_build_wheel. It is absolutely a historical artifact
but I need to work on one issue at a time. The next issue will be replacing
egg_info in pip with prepare_metadata_for_build_wheel.

2017-09-04 19:34 GMT-05:00 Nathaniel Smith <njs at pobox.com>:

> On Mon, Sep 4, 2017 at 5:09 PM, xoviat <xoviat at gmail.com> wrote:
> > Nathaniel:
> >
> > Pip requires egg_info to discover dependencies of source distributions so
> > that it can build wheels all at once after downloading the requirements.
> I
> > need to move pip off of egg_info as soon as possible and dist_info is
> > required to do that.
>
> "Requires" is a strong word -- AFAIK this is just a historical
> artifact. I don't really know what you're talking about in the second
> sentence.
>
> The only reason I can think of that setuptools would need a dist_info
> command would be to implement the PEP 517 prepare_wheel_metadata hook.
> But this hook is optional and in fact provides no value right now, so
> it can't be a blocker for anything. (In fact I can't see any reason
> why pip would ever call it before the resolver lands.) So either (a)
> there's some other reason you want a dist_info command, (b) there's
> some reason I'm missing why prepare_wheel_metadata matters, or (c) one
> of us is misunderstanding something :-).
>
> -n
>
> > 2017-09-03 21:00 GMT-05:00 Nathaniel Smith <njs at pobox.com>:
> >>
> >> On Sun, Sep 3, 2017 at 11:14 AM, xoviat <xoviat at gmail.com> wrote:
> >> > Just an update for everyone here:
> >> >
> >> > 1. We're currently waiting on the implementation of the 'dist_info"
> >> > command
> >> > in the wheel project.
> >> > 2. Once that is done we can switch pip over to reading dist-info
> rather
> >> > than
> >> > egg_info.
> >> > 3. Then we can move the backend over to setuptools. Because Jacob has
> a
> >> > much
> >> > more efficient release system than pip, I anticipate having a release
> of
> >> > setuptools first and then we can switch pip over to requiring a newer
> >> > setuptools via PEP 518.
> >>
> >> I don't think pip actually has any use for the PEP 517
> >> prepare_wheel_metadata hook right now though? Historically 'setup.py
> >> egg-info' was needed to kluge around unwanted behavior in 'setup.py
> >> install', but with a PEP 517 backend that's irrelevant because
> >> 'setup.py install' is never used. And in the future when pip has a
> >> real resolver, then prepare_wheel_metadata should allow some
> >> optimizations. But right now, prepare_wheel_metadata is completely
> >> useless AFAIK.
> >>
> >> So why is 'setup.py dist_info' a blocker for things?
> >>
> >> -n
> >>
> >> --
> >> Nathaniel J. Smith -- https://vorpus.org
> >
> >
>
>
>
> --
> Nathaniel J. Smith -- https://vorpus.org
>
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