[Python-Dev] Safely importing zip files with C extensions

[Stefan Behnel]

Vinay Sajip, 27.03.2013 20:38:
> >>> w = Wheel('/tmp/simplejson-3.1.2-cp27-none-linux_x86_64.whl')
> >>> w.mount()
> >>> import simplejson._speedups
> >>> dir(simplejson._speedups)
> ['__doc__', '__file__', '__loader__', '__name__', '__package__',
>  'encode_basestring_ascii', 'make_encoder', 'make_scanner', 'scanstring']
> >>> simplejson._speedups.__file__
> '/home/vinay/.distlib/dylib-cache/simplejson/_speedups.so'

I've always hated this setuptools misfeature of copying C extensions from
an installed archive into a user directory, one for each user. At least
during normal installation, they should be properly unpacked into normal
shared library files in the file system.

Whether it then makes sense to special case one-shot trial imports like the
above without installation is a bit of a different question, but I don't
see a compelling reason for adding complexity here. It's not really an
important use case.

Stefan