[Distutils] why this version spec does not work?

[P.J. Eby]

At 06:46 PM 8/23/2010 +0200, Adam GROSZER wrote:
>Hello,
>
>I have here this version spec in setup.py:
>'zope.testing >=3.6.0,<3.10.0',
>
>but zc.buildout does not get it right.
>Source is here:
>svn://svn.zope.org/repos/main/zc.recipe.testrunner/branches/1.2.1
>Output is here:
>http://paste.lisp.org/+2FSQ
>
>Why on earth does zc.buildout pick zope.testing = 3.10.0 with the
>above spec??

That's really odd; it must be something in buildout, as setuptools' 
Requirement objects seem to do the right thing:

 >>> from pkg_resources import Requirement, parse_version
 >>> r=Requirement.parse('zope.testing >=3.6.0,<3.10.0')
 >>> '3.6' in r
True
 >>> '3.10' in r
False
 >>> '3.10.0' in r
False