comparison hgext/uncommit.py @ 35182:867990238dc6

unamend: move fb extension unamend to core

unamend extension adds an unamend command which undoes the effect of the amend
command. This patch moves the unamend command from that extension to uncommit
extension and this one does not completely undoes the effect of amend command as
it creates a new commit, rather than reviving the old one back.

This also adds tests for the same.

.. feature::

   A new unamend command in uncommit extension which undoes the effect of the
   amend command by creating a new changeset which was there before amend and
   moving the changes that were amended to the working directory.

Differential Revision: https://phab.mercurial-scm.org/D821

35181:d4805a5e7e70

    context,
    copies,
    error,
    node,
    obsolete,
    pycompat,
    registrar,
    scmutil,
)

            scmutil.cleanupnodes(repo, mapping, 'uncommit')

            with repo.dirstate.parentchange():
                repo.dirstate.setparents(newid, node.nullid)
                _uncommitdirstate(repo, old, match)

35182:867990238dc6

    context,
    copies,
    error,
    node,
    obsolete,
    obsutil,
    pycompat,
    registrar,
    scmutil,
)

            scmutil.cleanupnodes(repo, mapping, 'uncommit')

            with repo.dirstate.parentchange():
                repo.dirstate.setparents(newid, node.nullid)
                _uncommitdirstate(repo, old, match)

def predecessormarkers(ctx):
    """yields the obsolete markers marking the given changeset as a successor"""
    for data in ctx.repo().obsstore.predecessors.get(ctx.node(), ()):
        yield obsutil.marker(ctx.repo(), data)

def _unamenddirstate(repo, predctx, curctx):
    """"""

    s = repo.status(predctx, curctx)
    ds = repo.dirstate
    copies = dict(ds.copies())
    for f in s.modified:
        if ds[f] == 'r':
            # modified + removed -> removed
            continue
        ds.normallookup(f)

    for f in s.added:
        if ds[f] == 'r':
            # added + removed -> unknown
            ds.drop(f)
        elif ds[f] != 'a':
            ds.add(f)

    for f in s.removed:
        if ds[f] == 'a':
            # removed + added -> normal
            ds.normallookup(f)
        elif ds[f] != 'r':
            ds.remove(f)

    # Merge old parent and old working dir copies
    oldcopies = {}
    for f in (s.modified + s.added):
        src = curctx[f].renamed()
        if src:
            oldcopies[f] = src[0]
    oldcopies.update(copies)
    copies = dict((dst, oldcopies.get(src, src))
                  for dst, src in oldcopies.iteritems())
    # Adjust the dirstate copies
    for dst, src in copies.iteritems():
        if (src not in predctx or dst in predctx or ds[dst] != 'a'):
            src = None
        ds.copy(src, dst)

@command('^unamend', [])
def unamend(ui, repo, **opts):
    """
    undo the most recent amend operation on a current changeset

    This command will roll back to the previous version of a changeset,
    leaving working directory in state in which it was before running
    `hg amend` (e.g. files modified as part of an amend will be
    marked as modified `hg status`)
    """

    unfi = repo.unfiltered()

    # identify the commit from which to unamend
    curctx = repo['.']

    with repo.wlock(), repo.lock(), repo.transaction('unamend'):
        if not curctx.mutable():
            raise error.Abort(_('cannot unamend public changesets'))

        # identify the commit to which to unamend
        markers = list(predecessormarkers(curctx))
        if len(markers) != 1:
            e = _("changeset must have one predecessor, found %i predecessors")
            raise error.Abort(e % len(markers))

        prednode = markers[0].prednode()
        predctx = unfi[prednode]

        if curctx.children():
            raise error.Abort(_("cannot unamend a changeset with children"))

        # add an extra so that we get a new hash
        # note: allowing unamend to undo an unamend is an intentional feature
        extras = predctx.extra()
        extras['unamend_source'] = curctx.node()

        def filectxfn(repo, ctx_, path):
            try:
                return predctx.filectx(path)
            except KeyError:
                return None

        # Make a new commit same as predctx
        newctx = context.memctx(repo,
                                parents=(predctx.p1(), predctx.p2()),
                                text=predctx.description(),
                                files=predctx.files(),
                                filectxfn=filectxfn,
                                user=predctx.user(),
                                date=predctx.date(),
                                extra=extras)
        # phase handling
        commitphase = curctx.phase()
        overrides = {('phases', 'new-commit'): commitphase}
        with repo.ui.configoverride(overrides, 'uncommit'):
            newprednode = repo.commitctx(newctx)

        newpredctx = repo[newprednode]

        changedfiles = []
        wctx = repo[None]
        wm = wctx.manifest()
        cm = newpredctx.manifest()
        dirstate = repo.dirstate
        diff = cm.diff(wm)
        changedfiles.extend(diff.iterkeys())

        with dirstate.parentchange():
            dirstate.setparents(newprednode, node.nullid)
            _unamenddirstate(repo, newpredctx, curctx)

        mapping = {curctx.node(): (newprednode,)}
        scmutil.cleanupnodes(repo, mapping, 'unamend')