hgext/pager.py

commands: wrapped docstrings at 78 characters

We have always had a left margin of 4 characters -- probably just
because that's how docstrings for top-level functions turn out by
default, but it also looks nice in the built-in help.

The docstrings were wrapped at 70 characters, which is the default for
Emacs. However, this gives a right margin of 10 characters in a
standard 80 character terminal.

I've now wrapped the relevant docstrings at 78 characters, effectively
killing the right margin. The asymmetric margins looked a bit odd and
some of the text looked cramped with a right margin, so Dirkjan and I
felt that it was best to remove it entirely. The two character gap was
kept to have some space between the border of the terminal -- it will
also make diffs involving the docstrings fit in a 80 character line.

# 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, incorporated herein by reference.
#
# To load the extension, add it to your .hgrc file:
#
#   [extension]
#   hgext.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='FSRX' less

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.

If you notice "BROKEN PIPE" error messages, you can disable them by
setting:

  [pager]
  quiet = True

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:

  [pager]
  attend = log

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 the global .hgrc
'''

import sys, os, signal
from mercurial import dispatch, util, extensions

def uisetup(ui):
    def pagecmd(orig, ui, options, cmd, cmdfunc):
        p = ui.config("pager", "pager", os.environ.get("PAGER"))
        if p and sys.stdout.isatty() and '--debugger' not in sys.argv:
            attend = ui.configlist('pager', 'attend')
            if (cmd in attend or
                (cmd not in ui.configlist('pager', 'ignore') and not attend)):
                sys.stderr = sys.stdout = util.popen(p, "wb")
                if ui.configbool('pager', 'quiet'):
                    signal.signal(signal.SIGPIPE, signal.SIG_DFL)
        return orig(ui, options, cmd, cmdfunc)

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