tests/test-walkrepo.py

branchmap: handle nullrev in setcachedata

906be86990 recently changed to switch from:

  self._rbcrevs[rbcrevidx:rbcrevidx + _rbcrecsize] = rec

to

  pack_into(_rbcrecfmt, self._rbcrevs, rbcrevidx, node, branchidx)

This causes an exception if rbcrevidx is -1 (i.e. the nullrev). The old code
handled this because python handles out of bound sets to arrays gracefully. The
new code throws because the self._rbcrevs buffer isn't long enough to write 8
bytes to.  Normally it would've been resized by the immediately preceding line,
but because the 0 length buffer is greater than the idx (-1) times the size, no
resize happens.

Setting the branch for the nullrev doesn't make sense anyway, so let's skip it.
This was caught by external tests in the Facebook extensions repo, but I've
added a test here that catches the issue.

from __future__ import absolute_import, print_function

import os

from mercurial import (
    hg,
    scmutil,
    ui as uimod,
    util,
)

chdir = os.chdir
mkdir = os.mkdir
pjoin = os.path.join

walkrepos = scmutil.walkrepos
checklink = util.checklink

u = uimod.ui.load()
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("sub2set 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()