comparison mercurial/copies.py @ 30193:368e27eb1ffa

copies: detect graft-like merges

Right now, nothing changes as a result of this, but we want to handle
grafts differently from ordinary merges later.

(Series developed together with Pierre-Yves David)

30192:509d29255c04

    # because the logic above is required for a simple copy to be kept across a
    # rebase.
    if repo.ui.configbool('experimental', 'disablecopytrace'):
        return {}, {}, {}, {}

    limit = _findlimit(repo, c1.rev(), c2.rev())
    if limit is None:
        # no common ancestor, no copies
        return {}, {}, {}, {}
    repo.ui.debug("  searching for copies back to rev %d\n" % limit)

30193:368e27eb1ffa

    # because the logic above is required for a simple copy to be kept across a
    # rebase.
    if repo.ui.configbool('experimental', 'disablecopytrace'):
        return {}, {}, {}, {}

    # In certain scenarios (e.g. graft, update or rebase), base can be
    # overridden We still need to know a real common ancestor in this case We
    # can't just compute _c1.ancestor(_c2) and compare it to ca, because there
    # can be multiple common ancestors, e.g. in case of bidmerge.  Because our
    # caller may not know if the revision passed in lieu of the CA is a genuine
    # common ancestor or not without explicitly checking it, it's better to
    # determine that here.
    #
    # base.descendant(wc) and base.descendant(base) are False, work around that
    _c1 = c1.p1() if c1.rev() is None else c1
    _c2 = c2.p1() if c2.rev() is None else c2
    # an endpoint is "dirty" if it isn't a descendant of the merge base
    # if we have a dirty endpoint, we need to trigger graft logic, and also
    # keep track of which endpoint is dirty
    dirtyc1 = not (base == _c1 or base.descendant(_c1))
    dirtyc2 = not (base== _c2 or base.descendant(_c2))
    graft = dirtyc1 or dirtyc2
    limit = _findlimit(repo, c1.rev(), c2.rev())
    if limit is None:
        # no common ancestor, no copies
        return {}, {}, {}, {}
    repo.ui.debug("  searching for copies back to rev %d\n" % limit)