doc/runrst

revert: mention update in hint of abort when reverting to non-parent

and explicitly warn about uncommitted changes

Examples:

BEFORE:

    $ hg par -q
    7:e81a2efd53d4
    $ hg revert -r 2
    abort: no files or directories specified
    (use --all to discard all changes)

AFTER:

  Clean working directory (revert can be easily undone, no edits to be lost):

    $ hg revert -r 2
    abort: no files or directories specified
    (use --all to revert all files, or 'hg update 2' to update)

  Uncommitted changes (revert --all *does* discard edits and is pretty hard to
  undo or even impossible if --no-backup is specified):

    $ hg revert -r 2
    abort: no files or directories specified
    (uncommitted changes, use --all to discard all changes, or 'hg update 2' to update)

#!/usr/bin/env python
#
# runrst - register custom roles and run correct writer
#
# Copyright 2010 Matt Mackall <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

"""usage: %s WRITER args...

where WRITER is the name of a Docutils writer such as 'html' or 'manpage'
"""

import sys
try:
    from docutils.parsers.rst import roles
    from docutils.core import publish_cmdline
    from docutils import nodes, utils
except ImportError:
    sys.stderr.write("abort: couldn't generate documentation: docutils "
                     "module is missing\n")
    sys.exit(-1)

def role_hg(name, rawtext, text, lineno, inliner,
            options={}, content=[]):
    text = "hg " + utils.unescape(text)
    linktext = nodes.literal(rawtext, text)
    parts = text.split()
    cmd, args = parts[1], parts[2:]
    if cmd == 'help' and args:
        cmd = args[0] # link to 'dates' for 'hg help dates'
    node = nodes.reference(rawtext, '', linktext,
                           refuri="hg.1.html#%s" % cmd)
    return [node], []

roles.register_local_role("hg", role_hg)

if __name__ == "__main__":
    if len(sys.argv) < 2:
        sys.stderr.write(__doc__ % sys.argv[0])
        sys.exit(1)

    writer = sys.argv[1]
    del sys.argv[1]

    publish_cmdline(writer_name=writer)