hgext/pager.py

merge: don't overwrite file untracked after remove, abort with 'untracked files'

Merge could overwrite untracked files and cause data loss.

Instead we now handle the 'local side removed file and has untracked file
instead' case as the 'other side added file that local has untracked' case:

  FILE: untracked file exists
  abort: untracked files in working directory differ from files in requested revision

It could perhaps make sense to create .orig files when overwriting, either
instead of aborting or when overwriting anyway because of force ... but for now
we stay consistent with similar 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.

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"))

        if p:
            attend = ui.configlist('pager', 'attend', attended)
            auto = options['pager'] == 'auto'
            always = util.parsebool(options['pager'])

            cmds, _ = cmdutil.findcmd(cmd, commands.table)

            ignore = ui.configlist('pager', 'ignore')
            for cmd in cmds:
                if (always or auto and
                    (cmd in attend or
                     (cmd not in 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)
                    break
        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']