view hgext/purge.py @ 36367:043e77f3be09

sshpeer: return framed file object when needed

Currently, wireproto.wirepeer has a default implementation of
_submitbatch() and sshv1peer has a very similar implementation.
The main difference is that sshv1peer is aware of the total amount
of bytes it can read whereas the default implementation reads the
stream until no more data is returned. The default implementation
works for HTTP, since there is a known end to HTTP responses (either
Content-Length or 0 sized chunk).

This commit teaches sshv1peer to use our just-introduced "cappedreader"
class for wrapping a file object to limit the number of bytes that
can be read. We do this by introducing an argument to specify whether
the response is framed. If set, we returned a cappedreader instance
instead of the raw pipe.

_call() always has framed responses. So we set this argument
unconditionally and then .read() the entirety of the result.
Strictly speaking, we don't need to use cappedreader in this case
and can inline frame decoding/read logic. But I like when things
are consistent. The overhead should be negligible.

_callstream() and _callcompressable() are special: whether framing
is used depends on the specific command. So, we define a set
of commands that have framed response. It currently only
contains "batch."

As a result of this change, the one-off implementation of
_submitbatch() in sshv1peer can be removed since it is now
safe to .read() the response's file object until end of stream.
cappedreader takes care of not overrunning the frame.

Differential Revision: https://phab.mercurial-scm.org/D2380

# Copyright (C) 2006 - Marco Barisione <[e-mail]>
#
# This is a small extension for Mercurial (https://mercurial-scm.org/)
# that removes files not known to mercurial
#
# This program was inspired by the "cvspurge" script contained in CVS
# utilities (http://www.red-bean.com/cvsutils/).
#
# For help on the usage of "hg purge" use:
#  hg help purge
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, see <http://www.gnu.org/licenses/>.

'''command to delete untracked files from the working directory'''
from __future__ import absolute_import

import os

from mercurial.i18n import _
from mercurial import (
    cmdutil,
    error,
    registrar,
    scmutil,
    util,
)

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 = 'ships-with-hg-core'

@command('purge|clean',
    [('a', 'abort-on-err', None, _('abort if an error occurs')),
    ('',  'all', None, _('purge ignored files too')),
    ('',  'dirs', None, _('purge empty directories')),
    ('',  'files', None, _('purge files')),
    ('p', 'print', None, _('print filenames instead of deleting them')),
    ('0', 'print0', None, _('end filenames with NUL, for use with xargs'
                            ' (implies -p/--print)')),
    ] + cmdutil.walkopts,
    _('hg purge [OPTION]... [DIR]...'))
def purge(ui, repo, *dirs, **opts):
    '''removes files not tracked by Mercurial

    Delete files not known to Mercurial. This is useful to test local
    and uncommitted changes in an otherwise-clean source tree.

    This means that purge will delete the following by default:

    - Unknown files: files marked with "?" by :hg:`status`
    - Empty directories: in fact Mercurial ignores directories unless
      they contain files under source control management

    But it will leave untouched:

    - Modified and unmodified tracked files
    - Ignored files (unless --all is specified)
    - New files added to the repository (with :hg:`add`)

    The --files and --dirs options can be used to direct purge to delete
    only files, only directories, or both. If neither option is given,
    both will be deleted.

    If directories are given on the command line, only files in these
    directories are considered.

    Be careful with purge, as you could irreversibly delete some files
    you forgot to add to the repository. If you only want to print the
    list of files that this program would delete, use the --print
    option.
    '''
    act = not opts.get('print')
    eol = '\n'
    if opts.get('print0'):
        eol = '\0'
        act = False # --print0 implies --print
    removefiles = opts.get('files')
    removedirs = opts.get('dirs')
    if not removefiles and not removedirs:
        removefiles = True
        removedirs = True

    def remove(remove_func, name):
        if act:
            try:
                remove_func(repo.wjoin(name))
            except OSError:
                m = _('%s cannot be removed') % name
                if opts.get('abort_on_err'):
                    raise error.Abort(m)
                ui.warn(_('warning: %s\n') % m)
        else:
            ui.write('%s%s' % (name, eol))

    match = scmutil.match(repo[None], dirs, opts)
    if removedirs:
        directories = []
        match.explicitdir = match.traversedir = directories.append
    status = repo.status(match=match, ignored=opts.get('all'), unknown=True)

    if removefiles:
        for f in sorted(status.unknown + status.ignored):
            if act:
                ui.note(_('removing file %s\n') % f)
            remove(util.unlink, f)

    if removedirs:
        for f in sorted(directories, reverse=True):
            if match(f) and not os.listdir(repo.wjoin(f)):
                if act:
                    ui.note(_('removing directory %s\n') % f)
                remove(os.rmdir, f)