tests/readlink.py

pypy: fix doctests for pypy optimizations

PyPy would sometime call __len__ at points where it things preallocating
the container makes sense. Change the doctests so they're using generator
expressions and not list comprehensions

#!/usr/bin/env python

import errno, os, sys

for f in sys.argv[1:]:
    try:
        print f, '->', os.readlink(f)
    except OSError as err:
        if err.errno != errno.EINVAL:
            raise
        print f, 'not a symlink'

sys.exit(0)