[Distutils] buildout.dumppickedversions and buildout_versions

[Jim Fulton]

On Sat, Dec 15, 2012 at 11:56 AM, Chris Withers <chris at simplistix.co.uk> wrote:
> On 15/12/2012 09:33, Lele Gaifax wrote:
>>
>> Alex Clark <aclark at aclark.net> writes:
>>
>>> 19:43 < cullerton> Folks, there's something wonky going on with
>>> buildout this morning. When I run bootstrap, it creates a buildout
>>> script using buildout 2.0.
>>> 0a4. This fails with an error (TypeError: get_dist() takes exactly 4
>>> arguments (3 given)). Changing the version to buildout 1.4.4 seems to
>>> fix things.
>>
>>
>> FYI, I just met the same error (using 2.0.0a5), and the culprit was the
>> buildout.dumppickedversion extension, that monkey-patches the
>> easy_install.py::Installer._get_dist() method (it surprised me at first
>> that the error message mentions “get_dist()” but at the referenced line
>> in easy_install.py there is a call to “_get_dist()”...). It took a pdb
>> session and a “p inspect.getmodule(self._get_dist)” to find out what's
>> going on.
>
>
> Yeah, the stuff that buildout.dumppickedversions and buildout_versions
> provide should just be in the core.
>
> Jim, if I worked up a pull request would you merge it?

Maybe :)  I tried to look at buildout.dumppickedversions and
buildout_versions and
I couldn't quite tell what they were for or how they were different.
Are they different?
Or are they 2 versions of the same thing?

http://pypi.python.org/pypi/buildout.dumppickedversions gives me a
fair idea what it
does, but http://pypi.python.org/pypi/buildout-versions looks like
almost the same
thing and http://packages.python.org/buildout_versions/index.html doesn't state
what problem it solves.

I realize that a tool to help manage version pins would be helpful. I
punted on this
when I added the versions feature.  Before adding this feature to buildout, I'd
like a clearer statement of what problems are being solved and what the approach
is.

Alternatively, I'd be open to adding an API to make writing an
extension possible
without depending on internal implementation details.

Jim

-- 
Jim Fulton
http://www.linkedin.com/in/jimfulton
Jerky is better than bacon! http://zo.pe/Kqm