tests/lockdelay.py

packaging: add Cosmic and Disco, remove Trusty and Artful

- Trusty was publicly supported until 2019-04-30
- Artful was publicly supported until 2018-07-19
- Cosmic was publicly supported until 2019-07-18
- Disco will be publicly supported until 2020-01

Cosmic is officially out-of-date, but since it still may be in use, and because
we didn't add it when it first came out, I think it would be nice to support it
until the next time somebody decides to update this list of Ubuntu releases.

Differential Revision: https://phab.mercurial-scm.org/D6761

# 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

def reposetup(ui, repo):

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