hgext/pager.py

bookmarks: check HG_PENDING strictly

Before this patch, checking HG_PENDING in bookmarks.py might cause
unintentional reading unrelated '.hg/bookmarks.pending' in, because it
just examines existence of HG_PENDING environment variable.

This patch uses txnutil.trypending() to check HG_PENDING strictly.

This patch also changes share extension.

Enabling share extension (+ bookmark sharing) makes
bookmarks._getbkfile() receive repo to be shared (= "srcrepo"). On the
other hand, HG_PENDING always refers current working repo (=
"currepo"), and bookmarks.pending is written only into currepo.

Therefore, we should try to read .hg/bookmarks.pending of currepo in
at first. If it doesn't exist, we try to read .hg/bookmarks of srcrepo
in.

Even after this patch, an external hook spawned in currepo can't see
pending changes in currepo via srcrepo, even though such changes
become visible after closing transaction, because there is no easy and
cheap way to know existence of pending changes in currepo via srcrepo.

Please see https://www.mercurial-scm.org/wiki/SharedRepository, too.

BTW, this patch may cause failure of bisect in the repository of
Mercurial itself, if examination at bisecting assumes that an external
hook can see all pending changes while nested transactions across
repositories.

This invisibility issue will be fixed by subsequent patch, which
allows HG_PENDING to refer multiple repositories.

# pager.py - display output using a pager
#
# Copyright 2008 David Soria Parra <[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.
#
# To load the extension, add it to your configuration file:
#
#   [extension]
#   pager =
#
# Run 'hg help pager' to get info on configuration.

'''browse command output with an external pager

To set the pager that should be used, set the application variable::

  [pager]
  pager = less -FRX

If no pager is set, the pager extensions uses the environment variable
$PAGER. If neither pager.pager, nor $PAGER is set, no pager is used.

You can disable the pager for certain commands by adding them to the
pager.ignore list::

  [pager]
  ignore = version, help, update

You can also enable the pager only for certain commands using
pager.attend. Below is the default list of commands to be paged::

  [pager]
  attend = annotate, cat, diff, export, glog, log, qdiff

Setting pager.attend to an empty value will cause all commands to be
paged.

If pager.attend is present, pager.ignore will be ignored.

Lastly, you can enable and disable paging for individual commands with
the attend-<command> option. This setting takes precedence over
existing attend and ignore options and defaults::

  [pager]
  attend-cat = false

To ignore global commands like :hg:`version` or :hg:`help`, you have
to specify them in your user configuration file.

To control whether the pager is used at all for an individual command,
you can use --pager=<value>::

  - use as needed: `auto`.
  - require the pager: `yes` or `on`.
  - suppress the pager: `no` or `off` (any unrecognized value
  will also work).

'''
from __future__ import absolute_import

from mercurial import (
    cmdutil,
    commands,
    dispatch,
    extensions,
    )

# 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'

def uisetup(ui):

    def pagecmd(orig, ui, options, cmd, cmdfunc):
        auto = options['pager'] == 'auto'
        if auto and not ui.pageractive:
            usepager = False
            attend = ui.configlist('pager', 'attend', attended)
            ignore = ui.configlist('pager', 'ignore')
            cmds, _ = cmdutil.findcmd(cmd, commands.table)

            for cmd in cmds:
                var = 'attend-%s' % cmd
                if ui.config('pager', var):
                    usepager = ui.configbool('pager', var)
                    break
                if (cmd in attend or
                     (cmd not in ignore and not attend)):
                    usepager = True
                    break

            if usepager:
                # Slight hack: the attend list is supposed to override
                # the ignore list for the pager extension, but the
                # core code doesn't know about attend, so we have to
                # lobotomize the ignore list so that the extension's
                # behavior is preserved.
                ui.setconfig('pager', 'ignore', '', 'pager')
                ui.pager('extension-via-attend-' + cmd)
        return orig(ui, options, cmd, cmdfunc)

    # Wrap dispatch._runcommand after color is loaded so color can see
    # ui.pageractive. Otherwise, if we loaded first, color's wrapped
    # dispatch._runcommand would run without having access to ui.pageractive.
    def afterloaded(loaded):
        extensions.wrapfunction(dispatch, '_runcommand', pagecmd)
    extensions.afterloaded('color', afterloaded)

attended = [
    'the-default-attend-list-is-now-empty-but-that-breaks-the-extension',
]