tests/lockdelay.py

tests: Solaris cmp complains about empty files, even with -s

When you compare an empty file, such as /dev/null, with a non-empty file,
Solaris cmp complains on stderr with "cmp: EOF on /dev/null", even if the
-s argument is present.  GNU cmp makes the complaint, but silences it with
-s.  We can change the pdiff utility to simply redirect stderr to /dev/null
so that we don't have to worry about this difference in the test files.

# Dummy extension that adds a delay after acquiring a lock.
#
# This extension can be used to test race conditions between lock acquisition.

from __future__ import absolute_import

import os
import time

from mercurial import (
    lock as lockmod,
)

class delaylock(lockmod.lock):
    def lock(self):
        delay = float(os.environ.get('HGPRELOCKDELAY', '0.0'))
        if delay:
            time.sleep(delay)
        res = super(delaylock, self).lock()
        delay = float(os.environ.get('HGPOSTLOCKDELAY', '0.0'))
        if delay:
            time.sleep(delay)
        return res

def extsetup(ui):
    lockmod.lock = delaylock