[Distutils] setuptools: Bug in requirement loading
Phillip J. Eby
pje at telecommunity.com
Wed Nov 2 20:38:09 CET 2005
At 12:17 PM 11/2/2005 -0600, Ian Bicking wrote:
>(got a little truncated, but ignoring that.) If "dist is None", i.e.,
>no egg for the requirement is yet loaded, the egg is loaded with
>"self.by_key.get(req.key)". req.key doesn't have any version
>information, it's just the package name.
Eep. That is indeed a bug.
>If I change the second "if dist is None" to "if dist is None or dist not
>in req" then at least I get a version conflict. But I thought
>setuptools 0.6a7 was able to load an egg besides the default version.
It is able to, as long as the egg is one required by the __main__
program. There is special startup logic that checks for VersionConflict on
application start, and then fudges things to work around it. It is not,
however, an all-purpose facility to allow loading non-default
versions. That would involve more complex refactoring and isn't something
I'll attempt in a minor release. (Indeed, I suspect that supporting it
properly would require a rethink of the entire WorkingSet API and
implementation, and perhaps a fair bit of hooking into Python's import
>Actually, I'm now confused how anything but the default version can be
Yeah, that's the bug all right.
>I'm having a hard time figuring out how I didn't notice this before.
Me too! I'm guessing this was introduced when I made some changes to
resolve() to avoid unnecessary directory scans. resolve() was previously
not even looking to see if the working set already contained a matching
Anyway, the simplest fix should be to change the 'elif dist not in req' to
'if dist not in req'.
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