view hgext/share.py @ 17889:ce7bc04d863b stable

icasefs: make case-folding collision detection as deletion aware (issue3648)

Before this patch, case-folding collision is checked simply between
manifests of each merged revisions.

So, files may be considered as colliding each other, even though one
of them is already deleted on one of merged branches: in such case,
merge causes deleting it, so case-folding collision doesn't occur.

This patch checks whether both of files colliding each other still
remain after merge or not, and ignores collision if at least one of
them is deleted by merge.

In the case that one of colliding files is deleted on one of merged
branches and changed on another, file is considered to still remain
after merge, even though it may be deleted by merge, if "deleting" of
it is chosen in "manifestmerge()".

This avoids fail to merge by case-folding collisions after choices
from "changing" and "deleting" of files.

This patch adds only tests for "removed remotely" code paths in
"_remains()", because other ones are tested by existing tests in
"test-casecollision-merge.t".

# 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__(ui, repo.root)

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

commands.norepo += " share"