On 17 March 2015 at 12:32, Donald Stufft <don...@stufft.io> wrote: > > On Mar 16, 2015, at 7:03 PM, Nick Coghlan <ncogh...@gmail.com> wrote: > > > On 17 Mar 2015 02:33, "Daniel Holth" <dho...@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.
Huh? I think the key tests are: - what happens with old tools - what happens with new tools With old tools it needs to not-break. With new tools it should be better :). Teaching pip, double-entered setup_requires (.cfg and .py). old tools keep working new tools are shiny (pip install -e / vcs then setup's easy_install call short-circuits doing nothing). Teaching only setuptools, double-entered old tools keep working new tools are not shiny, because pip isn't doing the install Teaching only setuptools, single entry old tools break (requirements absent, or you have a versioned dep on setuptools in setup.py and omg the pain) new tools are not shiny, same reason Teaching setuptools and pip, single entry old tools break - as above new tools are shiny (because pip either asks setuptools or reads setup.cfg, whatever) So I think we must teach pip, and we may teach setuptools. -Rob -- Robert Collins <rbtcoll...@hp.com> Distinguished Technologist HP Converged Cloud _______________________________________________ Distutils-SIG maillist - Distutils-SIG@python.org https://mail.python.org/mailman/listinfo/distutils-sig