hgext/blackbox.py

destutil: ensure we offer 'hg update' hint when not at head in all cases

In the merge case, we abort if the working copy is not at head, offering to
run 'hg update' in the hint instead. In the rebase case, we do not abort in that
case. Yet if no rebase destination are found, it still make sense to hint the
user about running 'hg update'. So we re-introduce a conditional using this
branch in the 'onheadcheck == False' case.

This will get used on rebase use this function.

# blackbox.py - log repository events to a file for post-mortem debugging
#
# Copyright 2010 Nicolas Dumazet
# Copyright 2013 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

"""log repository events to a blackbox for debugging

Logs event information to .hg/blackbox.log to help debug and diagnose problems.
The events that get logged can be configured via the blackbox.track config key.
Examples::

  [blackbox]
  track = *

  [blackbox]
  track = command, commandfinish, commandexception, exthook, pythonhook

  [blackbox]
  track = incoming

  [blackbox]
  # limit the size of a log file
  maxsize = 1.5 MB
  # rotate up to N log files when the current one gets too big
  maxfiles = 3

"""

from __future__ import absolute_import

import errno
import re

from mercurial.i18n import _
from mercurial import (
    cmdutil,
    util,
)

cmdtable = {}
command = cmdutil.command(cmdtable)
# Note for extension authors: ONLY specify testedwith = 'internal' 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 = 'internal'
lastblackbox = None

def wrapui(ui):
    class blackboxui(ui.__class__):
        @util.propertycache
        def track(self):
            return self.configlist('blackbox', 'track', ['*'])

        def _openlogfile(self):
            def rotate(oldpath, newpath):
                try:
                    self._bbvfs.unlink(newpath)
                except OSError as err:
                    if err.errno != errno.ENOENT:
                        self.debug("warning: cannot remove '%s': %s\n" %
                                   (newpath, err.strerror))
                try:
                    if newpath:
                        self._bbvfs.rename(oldpath, newpath)
                except OSError as err:
                    if err.errno != errno.ENOENT:
                        self.debug("warning: cannot rename '%s' to '%s': %s\n" %
                                   (newpath, oldpath, err.strerror))

            fp = self._bbvfs('blackbox.log', 'a')
            maxsize = self.configbytes('blackbox', 'maxsize', 1048576)
            if maxsize > 0:
                st = self._bbvfs.fstat(fp)
                if st.st_size >= maxsize:
                    path = fp.name
                    fp.close()
                    maxfiles = self.configint('blackbox', 'maxfiles', 7)
                    for i in xrange(maxfiles - 1, 1, -1):
                        rotate(oldpath='%s.%d' % (path, i - 1),
                               newpath='%s.%d' % (path, i))
                    rotate(oldpath=path,
                           newpath=maxfiles > 0 and path + '.1')
                    fp = self._bbvfs('blackbox.log', 'a')
            return fp

        def log(self, event, *msg, **opts):
            global lastblackbox
            super(blackboxui, self).log(event, *msg, **opts)

            if not '*' in self.track and not event in self.track:
                return

            if util.safehasattr(self, '_blackbox'):
                blackbox = self._blackbox
            elif util.safehasattr(self, '_bbvfs'):
                try:
                    self._blackbox = self._openlogfile()
                except (IOError, OSError) as err:
                    self.debug('warning: cannot write to blackbox.log: %s\n' %
                               err.strerror)
                    del self._bbvfs
                    self._blackbox = None
                blackbox = self._blackbox
            else:
                # certain ui instances exist outside the context of
                # a repo, so just default to the last blackbox that
                # was seen.
                blackbox = lastblackbox

            if blackbox:
                date = util.datestr(None, '%Y/%m/%d %H:%M:%S')
                user = util.getuser()
                pid = str(util.getpid())
                formattedmsg = msg[0] % msg[1:]
                try:
                    blackbox.write('%s %s (%s)> %s' %
                                   (date, user, pid, formattedmsg))
                    blackbox.flush()
                except IOError as err:
                    self.debug('warning: cannot write to blackbox.log: %s\n' %
                               err.strerror)
                lastblackbox = blackbox

        def setrepo(self, repo):
            self._bbvfs = repo.vfs

    ui.__class__ = blackboxui

def uisetup(ui):
    wrapui(ui)

def reposetup(ui, repo):
    # During 'hg pull' a httppeer repo is created to represent the remote repo.
    # It doesn't have a .hg directory to put a blackbox in, so we don't do
    # the blackbox setup for it.
    if not repo.local():
        return

    if util.safehasattr(ui, 'setrepo'):
        ui.setrepo(repo)

@command('^blackbox',
    [('l', 'limit', 10, _('the number of events to show')),
    ],
    _('hg blackbox [OPTION]...'))
def blackbox(ui, repo, *revs, **opts):
    '''view the recent repository events
    '''

    if not repo.vfs.exists('blackbox.log'):
        return

    limit = opts.get('limit')
    blackbox = repo.vfs('blackbox.log', 'r')
    lines = blackbox.read().split('\n')

    count = 0
    output = []
    for line in reversed(lines):
        if count >= limit:
            break

        # count the commands by matching lines like: 2013/01/23 19:13:36 root>
        if re.match('^\d{4}/\d{2}/\d{2} \d{2}:\d{2}:\d{2} .*> .*', line):
            count += 1
        output.append(line)

    ui.status('\n'.join(reversed(output)))