help: add web commands to help documentation

The capabilities and URL endpoints of the hgweb server can currently
only be inferred by looking at links in `hg serve` output or by reading
the source code. I've frequently found myself wanting to quickly see
what URLs and capabilities are available.

This patch teaches the help system how to display information about
web commands and their URLs. Using a mechanism similar to revsets,
templates, etc, we can now iterate over the docstrings of registered
web command functions and display them in the help output.

Unfortunately, web commands don't currently have docstrings, so the
output is currently empty. This will be addressed in the following
patches. I apologize for the patch bomb.

mercurial/help.py

@@ -1,504 +1,506 b''
 # help.py - help data for mercurial
 #
 # Copyright 2006 Matt Mackall <[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.
 
 from i18n import gettext, _
 import itertools, os
 import error
 import extensions, revset, fileset, templatekw, templatefilters, filemerge
 import encoding, util, minirst
 import cmdutil
+import hgweb.webcommands as webcommands
 
 def listexts(header, exts, indent=1, showdeprecated=False):
     '''return a text listing of the given extensions'''
     rst = []
     if exts:
         rst.append('\n%s\n\n' % header)
         for name, desc in sorted(exts.iteritems()):
             if '(DEPRECATED)' in desc and not showdeprecated:
                 continue
             rst.append('%s:%s: %s\n' % (' ' * indent, name, desc))
     return rst
 
 def extshelp():
     rst = loaddoc('extensions')().splitlines(True)
     rst.extend(listexts(
         _('enabled extensions:'), extensions.enabled(), showdeprecated=True))
     rst.extend(listexts(_('disabled extensions:'), extensions.disabled()))
     doc = ''.join(rst)
     return doc
 
 def optrst(header, options, verbose):
     data = []
     multioccur = False
     for option in options:
         if len(option) == 5:
             shortopt, longopt, default, desc, optlabel = option
         else:
             shortopt, longopt, default, desc = option
             optlabel = _("VALUE") # default label
 
         if not verbose and ("DEPRECATED" in desc or _("DEPRECATED") in desc):
             continue
 
         so = ''
         if shortopt:
             so = '-' + shortopt
         lo = '--' + longopt
         if default:
             desc += _(" (default: %s)") % default
 
         if isinstance(default, list):
             lo += " %s [+]" % optlabel
             multioccur = True
         elif (default is not None) and not isinstance(default, bool):
             lo += " %s" % optlabel
 
         data.append((so, lo, desc))
 
     if multioccur:
         header += (_(" ([+] can be repeated)"))
 
     rst = ['\n%s:\n\n' % header]
     rst.extend(minirst.maketable(data, 1))
 
     return ''.join(rst)
 
 def indicateomitted(rst, omitted, notomitted=None):
     rst.append('\n\n.. container:: omitted\n\n    %s\n\n' % omitted)
     if notomitted:
         rst.append('\n\n.. container:: notomitted\n\n    %s\n\n' % notomitted)
 
 def topicmatch(kw):
     """Return help topics matching kw.
 
     Returns {'section': [(name, summary), ...], ...} where section is
     one of topics, commands, extensions, or extensioncommands.
     """
     kw = encoding.lower(kw)
     def lowercontains(container):
         return kw in encoding.lower(container)  # translated in helptable
     results = {'topics': [],
                'commands': [],
                'extensions': [],
                'extensioncommands': [],
                }
     for names, header, doc in helptable:
         # Old extensions may use a str as doc.
         if (sum(map(lowercontains, names))
             or lowercontains(header)
             or (callable(doc) and lowercontains(doc()))):
             results['topics'].append((names[0], header))
     import commands # avoid cycle
     for cmd, entry in commands.table.iteritems():
         if len(entry) == 3:
             summary = entry[2]
         else:
             summary = ''
         # translate docs *before* searching there
         docs = _(getattr(entry[0], '__doc__', None)) or ''
         if kw in cmd or lowercontains(summary) or lowercontains(docs):
             doclines = docs.splitlines()
             if doclines:
                 summary = doclines[0]
             cmdname = cmd.split('|')[0].lstrip('^')
             results['commands'].append((cmdname, summary))
     for name, docs in itertools.chain(
         extensions.enabled(False).iteritems(),
         extensions.disabled().iteritems()):
         # extensions.load ignores the UI argument
         mod = extensions.load(None, name, '')
         name = name.split('.')[-1]
         if lowercontains(name) or lowercontains(docs):
             # extension docs are already translated
             results['extensions'].append((name, docs.splitlines()[0]))
         for cmd, entry in getattr(mod, 'cmdtable', {}).iteritems():
             if kw in cmd or (len(entry) > 2 and lowercontains(entry[2])):
                 cmdname = cmd.split('|')[0].lstrip('^')
                 if entry[0].__doc__:
                     cmddoc = gettext(entry[0].__doc__).splitlines()[0]
                 else:
                     cmddoc = _('(no help text available)')
                 results['extensioncommands'].append((cmdname, cmddoc))
     return results
 
 def loaddoc(topic):
     """Return a delayed loader for help/topic.txt."""
 
     def loader():
         docdir = os.path.join(util.datapath, 'help')
         path = os.path.join(docdir, topic + ".txt")
         doc = gettext(util.readfile(path))
         for rewriter in helphooks.get(topic, []):
             doc = rewriter(topic, doc)
         return doc
 
     return loader
 
 helptable = sorted([
     (["config", "hgrc"], _("Configuration Files"), loaddoc('config')),
     (["dates"], _("Date Formats"), loaddoc('dates')),
     (["patterns"], _("File Name Patterns"), loaddoc('patterns')),
     (['environment', 'env'], _('Environment Variables'),
      loaddoc('environment')),
     (['revisions', 'revs'], _('Specifying Single Revisions'),
      loaddoc('revisions')),
     (['multirevs', 'mrevs'], _('Specifying Multiple Revisions'),
      loaddoc('multirevs')),
     (['revsets', 'revset'], _("Specifying Revision Sets"), loaddoc('revsets')),
     (['filesets', 'fileset'], _("Specifying File Sets"), loaddoc('filesets')),
     (['diffs'], _('Diff Formats'), loaddoc('diffs')),
     (['merge-tools', 'mergetools'], _('Merge Tools'), loaddoc('merge-tools')),
     (['templating', 'templates', 'template', 'style'], _('Template Usage'),
      loaddoc('templates')),
     (['urls'], _('URL Paths'), loaddoc('urls')),
     (["extensions"], _("Using Additional Features"), extshelp),
     (["subrepos", "subrepo"], _("Subrepositories"), loaddoc('subrepos')),
     (["hgweb"], _("Configuring hgweb"), loaddoc('hgweb')),
     (["glossary"], _("Glossary"), loaddoc('glossary')),
     (["hgignore", "ignore"], _("Syntax for Mercurial Ignore Files"),
      loaddoc('hgignore')),
     (["phases"], _("Working with Phases"), loaddoc('phases')),
 ])
 
 # Map topics to lists of callable taking the current topic help and
 # returning the updated version
 helphooks = {}
 
 def addtopichook(topic, rewriter):
     helphooks.setdefault(topic, []).append(rewriter)
 
 def makeitemsdoc(topic, doc, marker, items):
     """Extract docstring from the items key to function mapping, build a
     .single documentation block and use it to overwrite the marker in doc
     """
     entries = []
     for name in sorted(items):
         text = (items[name].__doc__ or '').rstrip()
         if not text:
             continue
         text = gettext(text)
         lines = text.splitlines()
         doclines = [(lines[0])]
         for l in lines[1:]:
             # Stop once we find some Python doctest
             if l.strip().startswith('>>>'):
                 break
             doclines.append('  ' + l.strip())
         entries.append('\n'.join(doclines))
     entries = '\n\n'.join(entries)
     return doc.replace(marker, entries)
 
 def addtopicsymbols(topic, marker, symbols):
     def add(topic, doc):
         return makeitemsdoc(topic, doc, marker, symbols)
     addtopichook(topic, add)
 
 addtopicsymbols('filesets', '.. predicatesmarker', fileset.symbols)
 addtopicsymbols('merge-tools', '.. internaltoolsmarker', filemerge.internals)
 addtopicsymbols('revsets', '.. predicatesmarker', revset.symbols)
 addtopicsymbols('templates', '.. keywordsmarker', templatekw.dockeywords)
 addtopicsymbols('templates', '.. filtersmarker', templatefilters.filters)
+addtopicsymbols('hgweb', '.. webcommandsmarker', webcommands.commands)
 
 def help_(ui, name, unknowncmd=False, full=True, **opts):
     '''
     Generate the help for 'name' as unformatted restructured text. If
     'name' is None, describe the commands available.
     '''
 
     import commands # avoid cycle
 
     def helpcmd(name):
         try:
             aliases, entry = cmdutil.findcmd(name, commands.table,
                                              strict=unknowncmd)
         except error.AmbiguousCommand, inst:
             # py3k fix: except vars can't be used outside the scope of the
             # except block, nor can be used inside a lambda. python issue4617
             prefix = inst.args[0]
             select = lambda c: c.lstrip('^').startswith(prefix)
             rst = helplist(select)
             return rst
 
         rst = []
 
         # check if it's an invalid alias and display its error if it is
         if getattr(entry[0], 'badalias', None):
             rst.append(entry[0].badalias + '\n')
             if entry[0].unknowncmd:
                 try:
                     rst.extend(helpextcmd(entry[0].cmdname))
                 except error.UnknownCommand:
                     pass
             return rst
 
         # synopsis
         if len(entry) > 2:
             if entry[2].startswith('hg'):
                 rst.append("%s\n" % entry[2])
             else:
                 rst.append('hg %s %s\n' % (aliases[0], entry[2]))
         else:
             rst.append('hg %s\n' % aliases[0])
         # aliases
         if full and not ui.quiet and len(aliases) > 1:
             rst.append(_("\naliases: %s\n") % ', '.join(aliases[1:]))
         rst.append('\n')
 
         # description
         doc = gettext(entry[0].__doc__)
         if not doc:
             doc = _("(no help text available)")
         if util.safehasattr(entry[0], 'definition'):  # aliased command
             if entry[0].definition.startswith('!'):  # shell alias
                 doc = _('shell alias for::\n\n    %s') % entry[0].definition[1:]
             else:
                 doc = _('alias for: hg %s\n\n%s') % (entry[0].definition, doc)
         doc = doc.splitlines(True)
         if ui.quiet or not full:
             rst.append(doc[0])
         else:
             rst.extend(doc)
         rst.append('\n')
 
         # check if this command shadows a non-trivial (multi-line)
         # extension help text
         try:
             mod = extensions.find(name)
             doc = gettext(mod.__doc__) or ''
             if '\n' in doc.strip():
                 msg = _('(use "hg help -e %s" to show help for '
                         'the %s extension)') % (name, name)
                 rst.append('\n%s\n' % msg)
         except KeyError:
             pass
 
         # options
         if not ui.quiet and entry[1]:
             rst.append(optrst(_("options"), entry[1], ui.verbose))
 
         if ui.verbose:
             rst.append(optrst(_("global options"),
                               commands.globalopts, ui.verbose))
 
         if not ui.verbose:
             if not full:
                 rst.append(_('\n(use "hg %s -h" to show more help)\n')
                            % name)
             elif not ui.quiet:
                 rst.append(_('\n(some details hidden, use --verbose '
                                'to show complete help)'))
 
         return rst
 
 
     def helplist(select=None):
         # list of commands
         if name == "shortlist":
             header = _('basic commands:\n\n')
         elif name == "debug":
             header = _('debug commands (internal and unsupported):\n\n')
         else:
             header = _('list of commands:\n\n')
 
         h = {}
         cmds = {}
         for c, e in commands.table.iteritems():
             f = c.split("|", 1)[0]
             if select and not select(f):
                 continue
             if (not select and name != 'shortlist' and
                 e[0].__module__ != commands.__name__):
                 continue
             if name == "shortlist" and not f.startswith("^"):
                 continue
             f = f.lstrip("^")
             if not ui.debugflag and f.startswith("debug") and name != "debug":
                 continue
             doc = e[0].__doc__
             if doc and 'DEPRECATED' in doc and not ui.verbose:
                 continue
             doc = gettext(doc)
             if not doc:
                 doc = _("(no help text available)")
             h[f] = doc.splitlines()[0].rstrip()
             cmds[f] = c.lstrip("^")
 
         rst = []
         if not h:
             if not ui.quiet:
                 rst.append(_('no commands defined\n'))
             return rst
 
         if not ui.quiet:
             rst.append(header)
         fns = sorted(h)
         for f in fns:
             if ui.verbose:
                 commacmds = cmds[f].replace("|",", ")
                 rst.append(" :%s: %s\n" % (commacmds, h[f]))
             else:
                 rst.append(' :%s: %s\n' % (f, h[f]))
 
         if not name:
             exts = listexts(_('enabled extensions:'), extensions.enabled())
             if exts:
                 rst.append('\n')
                 rst.extend(exts)
 
             rst.append(_("\nadditional help topics:\n\n"))
             topics = []
             for names, header, doc in helptable:
                 topics.append((names[0], header))
             for t, desc in topics:
                 rst.append(" :%s: %s\n" % (t, desc))
 
         if ui.quiet:
             pass
         elif ui.verbose:
             rst.append('\n%s\n' % optrst(_("global options"),
                                          commands.globalopts, ui.verbose))
             if name == 'shortlist':
                 rst.append(_('\n(use "hg help" for the full list '
                              'of commands)\n'))
         else:
             if name == 'shortlist':
                 rst.append(_('\n(use "hg help" for the full list of commands '
                              'or "hg -v" for details)\n'))
             elif name and not full:
                 rst.append(_('\n(use "hg help %s" to show the full help '
                              'text)\n') % name)
             elif name and cmds and name in cmds.keys():
                 rst.append(_('\n(use "hg help -v -e %s" to show built-in '
                              'aliases and global options)\n') % name)
             else:
                 rst.append(_('\n(use "hg help -v%s" to show built-in aliases '
                              'and global options)\n')
                            % (name and " " + name or ""))
         return rst
 
     def helptopic(name):
         for names, header, doc in helptable:
             if name in names:
                 break
         else:
             raise error.UnknownCommand(name)
 
         rst = [minirst.section(header)]
 
         # description
         if not doc:
             rst.append("    %s\n" % _("(no help text available)"))
         if callable(doc):
             rst += ["    %s\n" % l for l in doc().splitlines()]
 
         if not ui.verbose:
             omitted = _('(some details hidden, use --verbose'
                          ' to show complete help)')
             indicateomitted(rst, omitted)
 
         try:
             cmdutil.findcmd(name, commands.table)
             rst.append(_('\nuse "hg help -c %s" to see help for '
                        'the %s command\n') % (name, name))
         except error.UnknownCommand:
             pass
         return rst
 
     def helpext(name):
         try:
             mod = extensions.find(name)
             doc = gettext(mod.__doc__) or _('no help text available')
         except KeyError:
             mod = None
             doc = extensions.disabledext(name)
             if not doc:
                 raise error.UnknownCommand(name)
 
         if '\n' not in doc:
             head, tail = doc, ""
         else:
             head, tail = doc.split('\n', 1)
         rst = [_('%s extension - %s\n\n') % (name.split('.')[-1], head)]
         if tail:
             rst.extend(tail.splitlines(True))
             rst.append('\n')
 
         if not ui.verbose:
             omitted = _('(some details hidden, use --verbose'
                          ' to show complete help)')
             indicateomitted(rst, omitted)
 
         if mod:
             try:
                 ct = mod.cmdtable
             except AttributeError:
                 ct = {}
             modcmds = set([c.split('|', 1)[0] for c in ct])
             rst.extend(helplist(modcmds.__contains__))
         else:
             rst.append(_('(use "hg help extensions" for information on enabling'
                        ' extensions)\n'))
         return rst
 
     def helpextcmd(name):
         cmd, ext, mod = extensions.disabledcmd(ui, name,
                                                ui.configbool('ui', 'strict'))
         doc = gettext(mod.__doc__).splitlines()[0]
 
         rst = listexts(_("'%s' is provided by the following "
                               "extension:") % cmd, {ext: doc}, indent=4)
         rst.append('\n')
         rst.append(_('(use "hg help extensions" for information on enabling '
                    'extensions)\n'))
         return rst
 
 
     rst = []
     kw = opts.get('keyword')
     if kw:
         matches = topicmatch(kw)
         for t, title in (('topics', _('Topics')),
                          ('commands', _('Commands')),
                          ('extensions', _('Extensions')),
                          ('extensioncommands', _('Extension Commands'))):
             if matches[t]:
                 rst.append('%s:\n\n' % title)
                 rst.extend(minirst.maketable(sorted(matches[t]), 1))
                 rst.append('\n')
         if not rst:
             msg = _('no matches')
             hint = _('try "hg help" for a list of topics')
             raise util.Abort(msg, hint=hint)
     elif name and name != 'shortlist':
         if unknowncmd:
             queries = (helpextcmd,)
         elif opts.get('extension'):
             queries = (helpext,)
         elif opts.get('command'):
             queries = (helpcmd,)
         else:
             queries = (helptopic, helpcmd, helpext, helpextcmd)
         for f in queries:
             try:
                 rst = f(name)
                 break
             except error.UnknownCommand:
                 pass
         else:
             if unknowncmd:
                 raise error.UnknownCommand(name)
             else:
                 msg = _('no such help topic: %s') % name
                 hint = _('try "hg help --keyword %s"') % name
                 raise util.Abort(msg, hint=hint)
     else:
         # program name
         if not ui.quiet:
             rst = [_("Mercurial Distributed SCM\n"), '\n']
         rst.extend(helplist())
 
     return ''.join(rst)

mercurial/help/hgweb.txt

@@ -1,79 +1,86 b''
 Mercurial's internal web server, hgweb, can serve either a single
 repository, or a tree of repositories. In the second case, repository
 paths and global options can be defined using a dedicated
 configuration file common to :hg:`serve`, ``hgweb.wsgi``,
 ``hgweb.cgi`` and ``hgweb.fcgi``.
 
 This file uses the same syntax as other Mercurial configuration files
 but recognizes only the following sections:
 
   - web
   - paths
   - collections
 
 The ``web`` options are thoroughly described in :hg:`help config`.
 
 The ``paths`` section maps URL paths to paths of repositories in the
 filesystem. hgweb will not expose the filesystem directly - only
 Mercurial repositories can be published and only according to the
 configuration.
 
 The left hand side is the path in the URL. Note that hgweb reserves
 subpaths like ``rev`` or ``file``, try using different names for
 nested repositories to avoid confusing effects.
 
 The right hand side is the path in the filesystem. If the specified
 path ends with ``*`` or ``**`` the filesystem will be searched
 recursively for repositories below that point.
 With ``*`` it will not recurse into the repositories it finds (except for
 ``.hg/patches``).
 With ``**`` it will also search inside repository working directories
 and possibly find subrepositories.
 
 In this example::
 
   [paths]
   /projects/a = /srv/tmprepos/a
   /projects/b = c:/repos/b
   / = /srv/repos/*
   /user/bob = /home/bob/repos/**
 
 - The first two entries make two repositories in different directories
   appear under the same directory in the web interface
 - The third entry will publish every Mercurial repository found in
   ``/srv/repos/``, for instance the repository ``/srv/repos/quux/``
   will appear as ``http://server/quux/``
 - The fourth entry will publish both ``http://server/user/bob/quux/``
   and ``http://server/user/bob/quux/testsubrepo/``
 
 The ``collections`` section is deprecated and has been superseded by
 ``paths``.
 
 URLs and Common Arguments
 =========================
 
 URLs under each repository have the form ``/{command}[/{arguments}]``
 where ``{command}`` represents the name of a command or handler and
 ``{arguments}`` represents any number of additional URL parameters
 to that command.
 
 The web server has a default style associated with it. Styles map to
 a collection of named templates. Each template is used to render a
 specific piece of data, such as a changeset or diff.
 
 The style for the current request can be overwritten two ways. First,
 if ``{command}`` contains a hyphen (``-``), the text before the hyphen
 defines the style. For example, ``/atom-log`` will render the ``log``
 command handler with the ``atom`` style. The second way to set the
 style is with the ``style`` query string argument. For example,
 ``/log?style=atom``. The hyphenated URL parameter is preferred.
 
 Not all templates are available for all styles. Attempting to use
 a style that doesn't have all templates defined may result in an error
 rendering the page.
 
 Many commands take a ``{revision}`` URL parameter. This defines the
 changeset to operate on. This is commonly specified as the short,
 12 digit hexidecimal abbreviation for the full 40 character unique
 revision identifier. However, any value described by
 :hg:`help revisions` typically works.
+
+Commands and URLs
+=================
+
+The following web commands and their URLs are available:
+
+  .. webcommandsmarker