view mercurial/help.py @ 17626:3a524b647897

context: add "descendant()" to changectx for efficient descendant examination

This patch adds "descendant()", which uses "revlog.descendant()" for
descendant examination, to changectx.

This implementation is more efficient than "new in old.descendants()"
expression, because:

  - "changectx.descendants()" creates temporary "changectx" objects,
    but "revlog.descendant()" doesn't

    "revlog.descendant()" checks only revision numbers of descendants.

  - "revlog.descendant()" stops scanning, when scanning of all
    revisions less than one of examination target is finished

    this can avoid useless scanning in "not descendant" case.

# 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, sys, os
import extensions, revset, fileset, templatekw, templatefilters, filemerge
import encoding, util, minirst

def listexts(header, exts, indent=1):
    '''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()):
            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()))
    rst.extend(listexts(_('disabled extensions:'), extensions.disabled()))
    doc = ''.join(rst)
    return doc

def optrst(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 _("DEPRECATED") in desc and not verbose:
            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))

    rst = minirst.maketable(data, 1)

    if multioccur:
        rst.append(_("\n[+] marked option can be specified multiple times\n"))

    return ''.join(rst)

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:
        if (sum(map(lowercontains, names))
            or lowercontains(header)
            or lowercontains(doc())):
            results['topics'].append((names[0], header))
    import commands # avoid cycle
    for cmd, entry in commands.table.iteritems():
        if cmd.startswith('debug'):
            continue
        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().iteritems(),
        extensions.disabled().iteritems()):
        # extensions.load ignores the UI argument
        mod = extensions.load(None, name, '')
        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():
        if util.mainfrozen():
            module = sys.executable
        else:
            module = __file__
        base = os.path.dirname(module)

        for dir in ('.', '..'):
            docdir = os.path.join(base, dir, 'help')
            if os.path.isdir(docdir):
                break

        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)