[Distutils] setup_requires for dev environments

[Donald Stufft]

> On Mar 16, 2015, at 7:03 PM, Nick Coghlan <ncoghlan at gmail.com> wrote:
> 
> 
> On 17 Mar 2015 02:33, "Daniel Holth" <dholth at gmail.com <mailto:dholth at gmail.com>> wrote:
> >
> > Problem: Users would like to be able to import stuff in setup.py. This
> > could be anything from a version fetcher to a replacement for
> > distutils itself. However, if setup.py is the only place to specify
> > these requirements there's a bit of a chicken and egg problem, unless
> > they have unusually good setuptools knowledge, especially if you want
> > to replace the  entire setup() implementation.
> >
> > Problem: Having easy_install do it is not what people want and misses
> > some important use cases.
> >
> > Problem: Based on empirical evidence PEP 426 will never be done. Its
> > current purpose is to shut down discussion of pragmatic solutions.
> 
> Slight correction here: one of my current aims with PEP 426 is deliberately discouraging the discussion of solutions that only work reliably if everyone switches to a new build system first. That's a) never going to happen; and b) one of the key mistakes the distutils2 folks made that significantly hindered adoption of their work, and I don't want us to repeat it.
> 
> My other key aim is to provide a public definition of what I think "good" looks like when it comes to software distribution, so I can more easily assess whether less radical proposals are still moving us closer to that goal.
> 
> Making pip (and perhaps easy_install) setup.cfg aware, such that it assumes the use of d2to1 (or a semantically equivalent tool) if setup.cfg is present and hence is able to skip invoking setup.py in relevant cases, sounds like just such a positive incremental step to me, as it increases the number of situations where pip can avoid executing a Turing complete "configuration" file, without impeding the eventual adoption of a more comprehensive solution.
> 
> I don't think that needs a PEP - just an RFE against pip to make it d2to1 aware for each use case where it's relevant, like installing setup.py dependencies. (And perhaps a similar RFE against setuptools)
> 
> Projects that choose to rely on that new feature will be setting a high minimum installer version for their users, but some projects will be OK with that (especially projects private to a single organisation after upgrading pip on their production systems).
> 
> Cheers,
> Nick.
> 
> 

I don’t think that’s going to work, because if you only make pip aware of it then you break ``python setup.py sdist``, if you make setuptools aware of it then you don’t need pip to be aware of it because we’ll get it for free from setuptools being aware of it.

---
Donald Stufft
PGP: 7C6B 7C5D 5E2B 6356 A926 F04F 6E3C BCE9 3372 DCFA

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/distutils-sig/attachments/20150316/b1906a4c/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 801 bytes
Desc: Message signed with OpenPGP using GPGMail
URL: <http://mail.python.org/pipermail/distutils-sig/attachments/20150316/b1906a4c/attachment-0001.sig>