doc/runrst

setup: unconditionally enable the `long-paths-support` option on Windows

I don't see anything talking about why this was experimental in the first place,
but maybe it was concern about the level of python2 support for it.  But now,
both `python.exe` and the PyOxidizer build of `hg.exe` have a manifest that
enables it, so leaving it off would mean some Mercurial installations could
operate on a repo with long paths, and others couldn't.  Note that only the wide
character functions (XxxW) will have the length restriction lifted.

Sadly, distutils applies `/MANIFEST:EMBED` to the linker in a way that can't
easily be turned off, so we can't use `/MANIFESTFILE` with `extra_preargs` on
`link_executable`.  Fortunately, the compiler object provides a path to the
`mt.exe` it found during initialization, because the previous incarnation seems
to have assumed it is being run within an activated Visual Studio environment.
That causes MSYS builds to fail, and probably would have broke the CI
environment.

#!/usr/bin/env python3
#
# runrst - register custom roles and run correct writer
#
# Copyright 2010 Olivia 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:
    import docutils.core as core
    import docutils.nodes as nodes
    import docutils.utils as utils
    import docutils.parsers.rst.roles as roles
except ImportError:
    sys.stderr.write(
        "abort: couldn't generate documentation: docutils "
        "module is missing\n"
    )
    sys.stderr.write(
        "please install python-docutils or see "
        "http://docutils.sourceforge.net/\n"
    )
    sys.exit(-1)


def role_hg(name, rawtext, text, lineno, inliner, options=None, content=None):
    text = "hg " + utils.unescape(text)
    linktext = nodes.literal(rawtext, text)
    parts = text.split()
    cmd, args = parts[1], parts[2:]
    refuri = "hg.1.html#%s" % cmd
    if cmd == 'help' and args:
        if args[0] == 'config':
            # :hg:`help config`
            refuri = "hgrc.5.html"
        elif args[0].startswith('config.'):
            # :hg:`help config.SECTION...`
            refuri = "hgrc.5.html#%s" % args[0].split('.', 2)[1]
        elif len(args) >= 2 and args[0] == '-c':
            # :hg:`help -c COMMAND ...` is equivalent to :hg:`COMMAND`
            # (mainly for :hg:`help -c config`)
            refuri = "hg.1.html#%s" % args[1]
        else:
            refuri = "hg.1.html#%s" % args[0]
    node = nodes.reference(rawtext, '', linktext, refuri=refuri)
    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]

    core.publish_cmdline(writer_name=writer)