view tests/readlink.py @ 18091:f7f8159caad3

ancestor: add lazy membership testing to lazyancestors

This also makes the perfancestorset command use lazy membership testing. In a
linear repository with over 400,000 commits, without this patch, hg
perfancestorset takes 0.80 seconds no matter how far behind we're looking.
With this patch, hg perfancestorset -- X takes:

    Rev X       Time
       -1      0.00s
    -4000      0.01s
   -20000      0.04s
   -80000      0.17s
  -200000      0.43s
  -300000      0.69s
        0      0.88s

Thus, for revisions close to tip, we're up to several orders of magnitude
faster. At 0 we're around 10% slower.

#!/usr/bin/env python

import errno, os, sys

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

sys.exit(0)