view tests/lockdelay.py @ 34940:c2b30348930f stable

dirstate: clean up when restoring identical backups

When a dirstate backup is restored, it is possible that no actual changes to
the dirstate have been made.  In this case, the backup is still a hardlink
to the original dirstate.

Unfortunately, `os.rename` silently fails (nothing happens, and no error
occurs) when `src` and `dst` are hardlinks to the same file.  As a result,
the backup is left lying around.  Over time, these files accumulate.

When restoring dirstate backups, check if the backup and the dirstate are
the same file, and if so, just delete the backup.

Differential Revision: https://phab.mercurial-scm.org/D1201

# 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