hgext/children.py

delta-find: introduce a _DeltaSearch object

That object represent the search of a good delta for one revision. It will
replace the interleaved generator currently in use. It will make the logic more
explicit and easier to split into different subclass for the algorithm variant.

We will move content gradually before doing deeper rework.

For now, we only move the `_candidategroups` function here. More will follow in
the same series.

# Mercurial extension to provide the 'hg children' command
#
# Copyright 2007 by Intevation GmbH <[e-mail]>
#
# Author(s):
# Thomas Arendsen Hein <[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.

'''command to display child changesets (DEPRECATED)

This extension is deprecated. You should use :hg:`log -r
"children(REV)"` instead.
'''


from mercurial.i18n import _
from mercurial import (
    cmdutil,
    logcmdutil,
    pycompat,
    registrar,
)

templateopts = cmdutil.templateopts

cmdtable = {}
command = registrar.command(cmdtable)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = b'ships-with-hg-core'


@command(
    b'children',
    [
        (
            b'r',
            b'rev',
            b'.',
            _(b'show children of the specified revision'),
            _(b'REV'),
        ),
    ]
    + templateopts,
    _(b'hg children [-r REV] [FILE]'),
    helpcategory=command.CATEGORY_CHANGE_NAVIGATION,
    inferrepo=True,
)
def children(ui, repo, file_=None, **opts):
    """show the children of the given or working directory revision

    Print the children of the working directory's revisions. If a
    revision is given via -r/--rev, the children of that revision will
    be printed. If a file argument is given, revision in which the
    file was last changed (after the working directory revision or the
    argument to --rev if given) is printed.

    Please use :hg:`log` instead::

        hg children => hg log -r "children(.)"
        hg children -r REV => hg log -r "children(REV)"

    See :hg:`help log` and :hg:`help revsets.children`.

    """
    rev = opts.get('rev')
    ctx = logcmdutil.revsingle(repo, rev)
    if file_:
        fctx = repo.filectx(file_, changeid=ctx.rev())
        childctxs = [fcctx.changectx() for fcctx in fctx.children()]
    else:
        childctxs = ctx.children()

    displayer = logcmdutil.changesetdisplayer(
        ui, repo, pycompat.byteskwargs(opts)
    )
    for cctx in childctxs:
        displayer.show(cctx)
    displayer.close()