view hgext/inotify/__init__.py @ 11638:79231258503b stable

transplant: crash if repo.commit() finds nothing to commit

(makes issue2135, issue2264 more obvious, but does nothing to fix
either one)

This seems to happen in two distinct cases:
  * patch.patch() claims success but changes nothing (e.g.
    the transplanted changeset adds an empty file that already
    exists)
  * patch.patch() makes changes, but repo.status() fails to report them

Both of these seem like bugs in other parts of Mercurial, so arguably
it's not transplant's job to detect the failure to commit.  However:
  * detecting the problem as soon as possible is desirable
  * it prevents a more obscure crash later, in transplants.write()
  * there might be other lurking (or future) bugs that cause
    repo.commit() to do nothing

Also, in the case of issue2264 (source changesets silently dropped by
transplant), the only way to spot the problem currently is the crash
in transplants.write().  Failure to transplant a patch should abort
immediately, whether it's user error (patch does not apply) or a
Mercurial bug (e.g. repo.status() failing to report changes).

# __init__.py - inotify-based status acceleration for Linux
#
# Copyright 2006, 2007, 2008 Bryan O'Sullivan <[e-mail]>
# Copyright 2007, 2008 Brendan Cully <[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.

'''accelerate status report using Linux's inotify service'''

# todo: socket permissions

from mercurial.i18n import _
import server
from client import client, QueryFailed

def serve(ui, repo, **opts):
    '''start an inotify server for this repository'''
    server.start(ui, repo.dirstate, repo.root, opts)

def debuginotify(ui, repo, **opts):
    '''debugging information for inotify extension

    Prints the list of directories being watched by the inotify server.
    '''
    cli = client(ui, repo)
    response = cli.debugquery()

    ui.write(_('directories being watched:\n'))
    for path in response:
        ui.write(('  %s/\n') % path)

def reposetup(ui, repo):
    if not hasattr(repo, 'dirstate'):
        return

    class inotifydirstate(repo.dirstate.__class__):

        # We'll set this to false after an unsuccessful attempt so that
        # next calls of status() within the same instance don't try again
        # to start an inotify server if it won't start.
        _inotifyon = True

        def status(self, match, subrepos, ignored, clean, unknown):
            files = match.files()
            if '.' in files:
                files = []
            if self._inotifyon and not ignored and not subrepos and not self._dirty:
                cli = client(ui, repo)
                try:
                    result = cli.statusquery(files, match, False,
                                            clean, unknown)
                except QueryFailed, instr:
                    ui.debug(str(instr))
                    # don't retry within the same hg instance
                    inotifydirstate._inotifyon = False
                    pass
                else:
                    if ui.config('inotify', 'debug'):
                        r2 = super(inotifydirstate, self).status(
                            match, [], False, clean, unknown)
                        for c, a, b in zip('LMARDUIC', result, r2):
                            for f in a:
                                if f not in b:
                                    ui.warn('*** inotify: %s +%s\n' % (c, f))
                            for f in b:
                                if f not in a:
                                    ui.warn('*** inotify: %s -%s\n' % (c, f))
                        result = r2
                    return result
            return super(inotifydirstate, self).status(
                match, subrepos, ignored, clean, unknown)

    repo.dirstate.__class__ = inotifydirstate

cmdtable = {
    'debuginotify':
        (debuginotify, [], ('hg debuginotify')),
    '^inserve':
        (serve,
         [('d', 'daemon', None, _('run server in background')),
          ('', 'daemon-pipefds', '',
           _('used internally by daemon mode'), _('NUM')),
          ('t', 'idle-timeout', '',
           _('minutes to sit idle before exiting'), _('NUM')),
          ('', 'pid-file', '',
           _('name of file to write process ID to'), _('FILE'))],
         _('hg inserve [OPTION]...')),
    }