tests/test-walkrepo.py

transactions: fix hg recover with fncache backups

The transaction backupfiles logic was broken for 'hg recover'.  The file format
is XXX\0XXX\0YYY\0YYY\0 but the parser did a couple things wrong. 1) It went one
step beyond the final \0 and tried to read past the end of the array. 2)
array[i:i+1] returns a single item, instead of two items as intended.

Added a test to catch it, which turns out to be the first actual 'hg recover'
test.

import os
from mercurial import hg, ui
from mercurial.scmutil import walkrepos
from mercurial.util import checklink
from os import mkdir, chdir
from os.path import join as pjoin

u = ui.ui()
sym = checklink('.')

hg.repository(u, 'top1', create=1)
mkdir('subdir')
chdir('subdir')
hg.repository(u, 'sub1', create=1)
mkdir('subsubdir')
chdir('subsubdir')
hg.repository(u, 'subsub1', create=1)
chdir(os.path.pardir)
if sym:
    os.symlink(os.path.pardir, 'circle')
    os.symlink(pjoin('subsubdir', 'subsub1'), 'subsub1')

def runtest():
    reposet = frozenset(walkrepos('.', followsym=True))
    if sym and (len(reposet) != 3):
        print "reposet = %r" % (reposet,)
        print ("Found %d repositories when I should have found 3"
               % (len(reposet),))
    if (not sym) and (len(reposet) != 2):
        print "reposet = %r" % (reposet,)
        print ("Found %d repositories when I should have found 2"
               % (len(reposet),))
    sub1set = frozenset((pjoin('.', 'sub1'),
                         pjoin('.', 'circle', 'subdir', 'sub1')))
    if len(sub1set & reposet) != 1:
        print "sub1set = %r" % (sub1set,)
        print "reposet = %r" % (reposet,)
        print "sub1set and reposet should have exactly one path in common."
    sub2set = frozenset((pjoin('.', 'subsub1'),
                         pjoin('.', 'subsubdir', 'subsub1')))
    if len(sub2set & reposet) != 1:
        print "sub2set = %r" % (sub2set,)
        print "reposet = %r" % (reposet,)
        print "sub1set and reposet should have exactly one path in common."
    sub3 = pjoin('.', 'circle', 'top1')
    if sym and sub3 not in reposet:
        print "reposet = %r" % (reposet,)
        print "Symbolic links are supported and %s is not in reposet" % (sub3,)

runtest()
if sym:
    # Simulate not having symlinks.
    del os.path.samestat
    sym = False
    runtest()