view hgext/pager.py @ 23719:34364a4b25eb

linkrev: work around linkrev to filtered entry in 'filelog' revset

This revset is used by 'hg log FILENAME'. This prevent bugs when used on
a repository with hidden revisions.

Instead of just discarding file revisions whose linkrevs point to filtered
revisions, we put them aside and post-process them trying to find a non-filtered
introduction. See inline documentation for details about how it works.

This only fixes some of the problems. Once again, more will be needed when we can
cannot rely on child revisions of a file to find linkrev-shadowned revisions.

A test is added for 'hg log' catching such cases.

# 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.

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, errno, shlex
from mercurial import commands, dispatch, util, extensions, cmdutil
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():
        if util.safehasattr(signal, "SIGINT"):
            signal.signal(signal.SIGINT, signal.SIG_IGN)
        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"))
        usepager = False
        always = util.parsebool(options['pager'])
        auto = options['pager'] == 'auto'

        if not p:
            pass
        elif always:
            usepager = True
        elif not auto:
            usepager = False
        else:
            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:
            ui.setconfig('ui', 'formatted', ui.formatted(), 'pager')
            ui.setconfig('ui', 'interactive', False, 'pager')
            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']