tests/readlink.py

contrib: install latest versions of Python

Let's keep our build environment modern.

We upgrade 3.5-3.8 on Linux. Just 3.7 and 3.8 on Windows because we
don't use <3.7 on Windows.

Differential Revision: https://phab.mercurial-scm.org/D9145

#!/usr/bin/env python

from __future__ import absolute_import, print_function

import errno
import os
import 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, '->', f, 'not a symlink')

sys.exit(0)