tests/lockdelay.py

commands: use the new API to access hidden changesets in various commands

In previous patches, we have added an internal API to unhide hidden changesets.
This patch makes the following command use that api in nowarn mode i.e. there
will be no warning while accessing hidden changesets.

cat, diff, export, files, heads, identify, log, manifest, parents, status

This patch also adds test demonstarting the behaviour.

.. feature:: Accessing hidden changesets

    Set config option 'experimental.directaccess = True' to access hidden
    changesets from read only commands.

Differential Revision: https://phab.mercurial-scm.org/D1735

# 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