view hgext/share.py @ 21990:48e32c2c499b stable

context: call normal on the right object

dirstate.normal is the method that marks files as unchanged/normal.

Rev 20a30cd41d21 started caching dirstate.normal in order to improve
performance. However, there was an error in the patch: taking the wlock, under
some conditions depending on platform, can cause a new dirstate object to be
created. Caching dirstate.normal before calling wlock would then cause the
fixup calls below to be on the old dirstate object, effectively disappearing
into the ether.

On Unix and Unix-like OSes, the condition under which we create a new dirstate
object is 'the dirstate file has been modified since the last time we opened
it'. This happens pretty rarely, so the object is usually the same -- there's
little impact.

On Windows, the condition is 'always'. This means files in the lookup state are
never marked normal, so the bug has a serious performance impact since all the
files in the lookup state are re-read every time hg status is run.

# Copyright 2006, 2007 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''share a common history between several working directories'''

from mercurial.i18n import _
from mercurial import cmdutil, hg, util

cmdtable = {}
command = cmdutil.command(cmdtable)
testedwith = 'internal'

@command('share',
    [('U', 'noupdate', None, _('do not create a working copy'))],
    _('[-U] SOURCE [DEST]'),
    norepo=True)
def share(ui, source, dest=None, noupdate=False):
    """create a new shared repository

    Initialize a new repository and working directory that shares its
    history with another repository.

    .. note::

       using rollback or extensions that destroy/modify history (mq,
       rebase, etc.) can cause considerable confusion with shared
       clones. In particular, if two shared clones are both updated to
       the same changeset, and one of them destroys that changeset
       with rollback, the other clone will suddenly stop working: all
       operations will fail with "abort: working directory has unknown
       parent". The only known workaround is to use debugsetparents on
       the broken clone to reset it to a changeset that still exists.
    """

    return hg.share(ui, source, dest, not noupdate)

@command('unshare', [], '')
def unshare(ui, repo):
    """convert a shared repository to a normal one

    Copy the store data to the repo and remove the sharedpath data.
    """

    if repo.sharedpath == repo.path:
        raise util.Abort(_("this is not a shared repo"))

    destlock = lock = None
    lock = repo.lock()
    try:
        # we use locks here because if we race with commit, we
        # can end up with extra data in the cloned revlogs that's
        # not pointed to by changesets, thus causing verify to
        # fail

        destlock = hg.copystore(ui, repo, repo.path)

        sharefile = repo.join('sharedpath')
        util.rename(sharefile, sharefile + '.old')

        repo.requirements.discard('sharedpath')
        repo._writerequirements()
    finally:
        destlock and destlock.release()
        lock and lock.release()

    # update store, spath, sopener and sjoin of repo
    repo.unfiltered().__init__(repo.baseui, repo.root)