[Distutils] Not installing the install_requires

[Jean-Paul Calderone]

On Wed, 15 Jul 2009 04:29:05 -0700 (PDT), Peter Bengtsson <peterbe at gmail.com> wrote:
>I've just made a package
>http://pypi.python.org/pypi/premailer
>
>To figure out if I've got it right I've tried installing it like
>this::
>
> [snip - install failure log]
>
>The setup.py
>(see http://github.com/peterbe/premailer/tree/master)
>contains the following:
>
>      install_requires=[
>        'lxml',
>      ],
>
>Why does easy_install not try to install lxml before it installs the
>package?

Because it has to evaluate your setup.py to learn that it requires lxml,
but your setup.py *also* requires lxml, apparently because you're trying
to avoid spelling our your package's version number more than once.  This
has been discussed recently on this list a couple times:

http://mail.python.org/pipermail/distutils-sig/2009-May/011913.html
http://mail.python.org/pipermail/distutils-sig/2009-July/012441.html

The gist is that there is no way to declare things which your setup.py
depends on, so if you depend on anything novel in it, it will probably
fail like this for someone.

Jean-Paul