tests/lockdelay.py

test-gpg: start gpg-agent by gpg-connect-agent only if GnuPG v2.1+ detected

Danek Duvall found that gpg-connect-agent of GnuPG 2.0 never starts gpg-agent
daemon. The 2.1 way is documented as "gpg-coonect-agent /bye" [1], which
appears to be different from the 2.0 way [2].

 [1]: https://www.gnupg.org/documentation/manuals/gnupg/Invoking-GPG_002dAGENT.html
 [2]: https://www.gnupg.org/documentation/manuals/gnupg-2.0/Invoking-GPG_002dAGENT.html

Since "gpg-agent --daemon" of GnuPG 2.1 never prints environment variables,
"eval $(gpg-agent --daemon)" would be valid only for GnuPG < 2.1, and we'll
need a different workaround for 2.0. I have no 2.0 environment, I won't
implement it.

# 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