[Distutils] Builders vs Installers

[Paul Moore]

On 28 March 2013 02:05, Nick Coghlan <ncoghlan at gmail.com> wrote:
> On Thu, Mar 28, 2013 at 11:43 AM, Donald Stufft <donald at stufft.io> wrote:
>> I don't think you can, nor should you be able to, explicitly depend on something that is a VCS checkout.
>
> I find it more useful to think of the issue as whether or not you
> allow publication of source tarballs to satisfy a dependency, or
> *require* publication of a fully populated sdist. If you allow raw
> source tarballs, then you effectively allow VCS checkouts as well. I
> prefer requiring an explicit publication step, but we also need to
> acknowledge that the installer ecosystem we're trying to replace
> allows them, and some people are relying on that feature.

To give a real-life example of this issue, on Windows IPython depends
on PyReadline. But the released version (1.7.x) of PyReadline is
Python 2 only. So if you are using IPython on Python 3, you have to
also depend on PyReadline from git.

Now IPython doesn't declare a dependency on the VCS version (it just
depends on "pyreadline"). And pyreadline is sufficiently stagnant that
it hasn't declared anything much. But as an *end user* I have to make
sure I force pip to install pyreadline from VCS if I want a working
system.

Paul.