Looking for duplicate modules

[rusi]

On Aug 23, 8:30 pm, Roy Smith <r... at panix.com> wrote:
> We got burned yesterday by a scenario which has burned us before.  We had multiple copies of a module in sys.path.  One (the one we wanted) was in our deployed code tree, the other was in /usr/local/lib/python/ or some such.  It was a particularly confusing situation because we *knew* we had uninstalled the copy in /usr/local/lib.  What we didn't know was that puppet was set up to check to make sure it was there and reinstalled it automagically if it ever disappeared!
>
> What often adds to the confusion in cases like this is that if you use a package manager (such as apt-get) to manage your module deployments, when you uninstall, the .py files get removed, but the .pyc's stay behind.
>
> I'm working on a tool which scans all the directories in sys.path and finds any modules which appear multiple times in the path.  It'll also call out any .pyc's it finds without matching py's.
>
> I know those are not strictly errors, but both of them are, for lack of a better term, "deployment smells" and something to be warned about.  Before I invest too much effort into building it, does such a tool already exist?

Not remotely an answer.
emacs has a list-load-path-shadows for the same/similar issue in
elisp.
As a language moves to being a system (programming) language, it seems
to me necessary that such a functionality is built into the language
and gets called as part of standard installation procedure.

>
> We're slowly moving more of our deployment to using virtualenv (with --no-site-packages), but we're not fully there yet.  And even when we get there, there will still be opportunities to make these sorts of mistakes.
>
> ---
> Roy Smith
> r... at panix.com