tests/md5sum.py

revset: add startdepth limit to ancestors() as internal option

This is necessary to implement the set{gen} (set subscript) operator. For
example, set{-n} will be translated to ancestors(set, depth=n, startdepth=n).

https://www.mercurial-scm.org/wiki/RevsetOperatorPlan#ideas_from_mpm

The UI is undecided and I doubt if the startdepth option would be actually
useful, so the option is hidden for now. 'depth' could be extended to take
min:max range, in which case, integer depth should select a single generation.

  ancestors(set, depth=:y)  # scan up to y-th generation
  ancestors(set, depth=x:)  # skip until (x-1)-th generation
  ancestors(set, depth=x)   # select only x-th generation

Any ideas are welcomed.

  # reverse(ancestors(tip)) using hg repo
  3) 0.075951
  4) 0.076175

#!/usr/bin/env python
#
# Based on python's Tools/scripts/md5sum.py
#
# This software may be used and distributed according to the terms
# of the PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2, which is
# GPL-compatible.

from __future__ import absolute_import

import os
import sys

try:
    import hashlib
    md5 = hashlib.md5
except ImportError:
    import md5
    md5 = md5.md5

try:
    import msvcrt
    msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
    msvcrt.setmode(sys.stderr.fileno(), os.O_BINARY)
except ImportError:
    pass

for filename in sys.argv[1:]:
    try:
        fp = open(filename, 'rb')
    except IOError as msg:
        sys.stderr.write('%s: Can\'t open: %s\n' % (filename, msg))
        sys.exit(1)

    m = md5()
    try:
        for data in iter(lambda: fp.read(8192), b''):
            m.update(data)
    except IOError as msg:
        sys.stderr.write('%s: I/O error: %s\n' % (filename, msg))
        sys.exit(1)
    sys.stdout.write('%s  %s\n' % (m.hexdigest(), filename))

sys.exit(0)