view hgext/pager.py @ 17551:a7b3fdaf768d

bookmark: take successors into account when updating (issue3561)

When we rewrite a bookmarked changeset, we want to update the
bookmark on its successors. But the successors are not descendants
of its precursor (by definition). This changeset alters the bookmarks
logic to update bookmark location if the newer location is a successor
of the old one[1].

note: valid destinations are in fact any kind of successors of any kind
      of descendants (recursively.)

This changeset requires the enabling of the obsolete feature in
some bookmark tests.

# 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.

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

The --pager=... option can also be used to control when the pager is
used. Use a boolean value like yes, no, on, off, or use auto for
normal behavior.
'''

import atexit, sys, os, signal, subprocess
from mercurial import commands, dispatch, util, extensions
from mercurial.i18n import _

testedwith = 'internal'

def _pagerfork(ui, p):
    if not util.safehasattr(os, 'fork'):
        sys.stdout = util.popen(p, 'wb')
        if ui._isatty(sys.stderr):
            sys.stderr = sys.stdout
        return
    fdin, fdout = os.pipe()
    pid = os.fork()
    if pid == 0:
        os.close(fdin)
        os.dup2(fdout, sys.stdout.fileno())
        if ui._isatty(sys.stderr):
            os.dup2(fdout, sys.stderr.fileno())
        os.close(fdout)
        return
    os.dup2(fdin, sys.stdin.fileno())
    os.close(fdin)
    os.close(fdout)
    try:
        os.execvp('/bin/sh', ['/bin/sh', '-c', p])
    except OSError, e:
        if e.errno == errno.ENOENT:
            # no /bin/sh, try executing the pager directly
            args = shlex.split(p)
            os.execvp(args[0], args)
        else:
            raise

def _pagersubprocess(ui, p):
    pager = subprocess.Popen(p, shell=True, bufsize=-1,
                             close_fds=util.closefds, stdin=subprocess.PIPE,
                             stdout=sys.stdout, stderr=sys.stderr)

    stdout = os.dup(sys.stdout.fileno())
    stderr = os.dup(sys.stderr.fileno())
    os.dup2(pager.stdin.fileno(), sys.stdout.fileno())
    if ui._isatty(sys.stderr):
        os.dup2(pager.stdin.fileno(), sys.stderr.fileno())

    @atexit.register
    def killpager():
        pager.stdin.close()
        os.dup2(stdout, sys.stdout.fileno())
        os.dup2(stderr, sys.stderr.fileno())
        pager.wait()

def _runpager(ui, p):
    # The subprocess module shipped with Python <= 2.4 is buggy (issue3533).
    # The compat version is buggy on Windows (issue3225), but has been shipping
    # with hg for a long time.  Preserve existing functionality.
    if sys.version_info >= (2, 5):
        _pagersubprocess(ui, p)
    else:
        _pagerfork(ui, p)

def uisetup(ui):
    if '--debugger' in sys.argv or not ui.formatted():
        return

    def pagecmd(orig, ui, options, cmd, cmdfunc):
        p = ui.config("pager", "pager", os.environ.get("PAGER"))

        if p:
            attend = ui.configlist('pager', 'attend', attended)
            auto = options['pager'] == 'auto'
            always = util.parsebool(options['pager'])
            if (always or auto and
                (cmd in attend or
                 (cmd not in ui.configlist('pager', 'ignore') and not attend))):
                ui.setconfig('ui', 'formatted', ui.formatted())
                ui.setconfig('ui', 'interactive', False)
                if util.safehasattr(signal, "SIGPIPE"):
                    signal.signal(signal.SIGPIPE, signal.SIG_DFL)
                _runpager(ui, p)
        return orig(ui, options, cmd, cmdfunc)

    extensions.wrapfunction(dispatch, '_runcommand', pagecmd)

def extsetup(ui):
    commands.globalopts.append(
        ('', 'pager', 'auto',
         _("when to paginate (boolean, always, auto, or never)"),
         _('TYPE')))

attended = ['annotate', 'cat', 'diff', 'export', 'glog', 'log', 'qdiff']