view hgext/share.py @ 18853:78d760aa3607

duplicatecopies: do not mark items not in the dirstate as copies

Consider the following repo:

  0 -- 1 (renames a to b)
    \
     - 2

If we're rebasing 2 onto 1, then duplicatecopies is called with arguments (2,
1). copies.pathcopies goes backwards from 1 to 0 and returns the pair dst = a,
src = b. Of course, since we're working on top of 2, at this point a doesn't
exist in the dirstate.

Extra entries in the copymap are currently harmless because the copymap is
only queried for items in the dirstate map. However, if the dirstate.copy
method becomes one of the sources used to determine which files have changed,
this will prove problematic.

Note that we can't avoid going backwards in general -- consider this repo:

  0 -- 1 (renames a to b)
    \
     - 2 (renames a to c)

Rebasing 2 onto 1 should produce a rename from b to c.

# 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 hg, commands, util

testedwith = 'internal'

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
       (e.g. tip).
    """

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

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.__init__(repo.baseui, repo.root)

cmdtable = {
    "share":
    (share,
     [('U', 'noupdate', None, _('do not create a working copy'))],
     _('[-U] SOURCE [DEST]')),
    "unshare":
    (unshare,
    [],
    ''),
}

commands.norepo += " share"