view hgext/children.py @ 45999:c4c7a6b61146

match: skip walking up the directory hierarchy if the number of pats are small

Previously, we would receive a path like abc/def/ghi and "walk up" the directory
hierarchy, checking abc/def, abc, and `b''` to see if they were in the set of
prefixes that this matcher covered. We did this indiscriminately - we generated
all of these paths even if the set of prefixes the matcher covered was
completely empty, which is the case for a lot of repos at my company (the narrow
matcher we use is usually non-recursive).

This brings the time for a rebase in one of my repos from 12.20s to 10.87s. In
this particular repo, this is entirely due to the `len(prefix_set) == 0` check,
as I do not have any recursive patterns in the narrowspec.

Differential Revision: https://phab.mercurial-scm.org/D9488

# 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 __future__ import absolute_import

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

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`.

    """
    opts = pycompat.byteskwargs(opts)
    rev = opts.get(b'rev')
    ctx = scmutil.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, opts)
    for cctx in childctxs:
        displayer.show(cctx)
    displayer.close()