tests/readlink.py

tags: describe all abnormal tag types in `hg tags -v`

In particular, this affects `git` and `git-remote` tags when using hg-git.

Test Plan:
I have not included an explicit test, as this is much more easily tested within the `hg-git` test suite.

Differential Revision: https://phab.mercurial-scm.org/D9639

#!/usr/bin/env python3

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)