merge: store commitinfo if these is a dc or cd conflict delete-changed or changed-delete conflicts can either be resolved by mergetool, if some tool is passed and using or by user choose something on prompt or user doing some `hg revert` after choosing the file to remain conflicted. If the user decides to keep the changed side, on commit we just reuse the parent filenode. This is mostly fine unless we are in a distributed environment and people are doing criss-cross merges. Since, we don't have recursive merges or any other way of describing the end result of the merge was an explicit choice and it should be differentiated from it's ancestors, merge algo during criss-cross merges fails to take in account the explicit choice made by user and end up with a what-can-be-said-wrong-merge. The solution which we are trying to fix this is by creating a filenode on commit instead of reusing the parent filenode. This helps differentiate between pre-merged filenode and post-merge filenode and kind of tells about the choice user made. To implement creating new filenode functionality, we store info about these files in mergestate so that we can read them on commit and force create a new filenode. Differential Revision: https://phab.mercurial-scm.org/D8988

# stack.py - Mercurial functions for stack definition
#
#  Copyright Matt Mackall <mpm@selenic.com> and other
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import


def getstack(repo, rev=None):
    """return a sorted smartrev of the stack containing either rev if it is
    not None or the current working directory parent.

    The stack will always contain all drafts changesets which are ancestors to
    the revision and are not merges.
    """
    if rev is None:
        rev = b'.'

    revspec = b'only(%s) and not public() and not ::merge()'
    revisions = repo.revs(revspec, rev)
    revisions.sort()
    return revisions