doc/runrst

tags-fnode-cache: skip building a changectx in getfnode

Building a changectx object is costly, doing it just to retrieve the revision
number is suboptimal. Directly fetching the revision number from the changelog
provide a sizeable speedup to `hg debugupdatecache`.

### data-env-vars.name           = mercurial-2018-08-01-zstd-sparse-revlog
  # benchmark.name               = debug-update-cache
  # benchmark.variants.pre-state = warm
before: 0.213229 seconds
after:  0.165577 seconds  (-22.35%)
  # data-env-vars.name           = mercurial-filtered-2019-11-22-zstd-sparse-revlog
before: 1.200383 seconds
after:  1.071618 seconds  (-10.73%)
  # data-env-vars.name           = mozilla-central-2018-08-01-zstd-sparse-revlog
before: 1.465735 seconds
after:  0.923128 seconds  (-37.02%)
  # data-env-vars.name           = mozilla-try-2019-02-18-zstd-sparse-revlog
before: 6.511771 seconds
after:  4.507316 seconds  (-30.78%)
  # data-env-vars.name           = netbeans-2018-08-01-zstd-sparse-revlog
before: 1.023007 seconds
after:  0.645026 seconds  (-36.95%)
  # data-env-vars.name           = pypy-2018-08-01-zstd-sparse-revlog
before: 0.381141 seconds
after:  0.268654 seconds  (-29.51%)

#!/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)