##// END OF EJS Templates
parsers: fail fast if Python has wrong minor version (issue4110)...
parsers: fail fast if Python has wrong minor version (issue4110) This change causes an informative ImportError to be raised when importing the parsers extension module if the minor version of the currently-running Python interpreter doesn't match that of the Python used when compiling the extension module. This change also exposes a parsers.versionerrortext constant in the C implementation of the module. Its presence can be used to determine whether this behavior is present in a version of the module. The value of the constant is the leading text of the ImportError raised and is set to "Python minor version mismatch". Here is an example of what the new error looks like: Traceback (most recent call last): File "test.py", line 1, in <module> import mercurial.parsers ImportError: Python minor version mismatch: The Mercurial extension modules were compiled with Python 2.7.6, but Mercurial is currently using Python with sys.hexversion=33883888: Python 2.5.6 (r256:88840, Nov 18 2012, 05:37:10) [GCC 4.2.1 Compatible Apple Clang 4.1 ((tags/Apple/clang-421.11.66))] at: /opt/local/Library/Frameworks/Python.framework/Versions/2.5/Resources/ Python.app/Contents/MacOS/Python The reason for raising an error in this scenario is that Python's C API is known not to be compatible from minor version to minor version, even if sys.api_version is the same. See for example this Python bug report about incompatibilities between 2.5 and 2.6+: http://bugs.python.org/issue8118 These incompatibilities can cause Mercurial to break in mysterious, unforeseen ways. For example, when Mercurial compiled with Python 2.7 was run with 2.5, the following crash occurred when running "hg status": http://bz.selenic.com/show_bug.cgi?id=4110 After this crash was fixed, running with Python 2.5 no longer crashes, but the following puzzling behavior still occurs: $ hg status ... File ".../mercurial/changelog.py", line 123, in __init__ revlog.revlog.__init__(self, opener, "00changelog.i") File ".../mercurial/revlog.py", line 251, in __init__ d = self._io.parseindex(i, self._inline) File ".../mercurial/revlog.py", line 158, in parseindex index, cache = parsers.parse_index2(data, inline) TypeError: data is not a string which can be reproduced more simply with: import mercurial.parsers as parsers parsers.parse_index2("", True) Both the crash and the TypeError occurred because the Python C API's PyString_Check() returns the wrong value when the C header files from Python 2.7 are run with Python 2.5. This is an example of an incompatibility of the sort mentioned in the Python bug report above. Failing fast with an informative error message results in a better user experience in cases like the above. The information in the ImportError also simplifies troubleshooting for those on Mercurial mailing lists, the bug tracker, etc. This patch only adds the version check to parsers.c, which is sufficient to affect command-line commands like "hg status" and "hg summary". An idea for a future improvement is to move the version-checking C code to a more central location, and have it run when importing all Mercurial extension modules and not just parsers.c.

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help.py
509 lines | 17.8 KiB | text/x-python | PythonLexer
Matt Mackall
Add basic support for help topics and a dates topic
r3795 # help.py - help data for mercurial
#
# Copyright 2006 Matt Mackall <mpm@selenic.com>
#
Martin Geisler
updated license to be explicit about GPL version 2
r8225 # This software may be used and distributed according to the terms of the
Matt Mackall
Update license to GPLv2+
r10263 # GNU General Public License version 2 or any later version.
Matt Mackall
Add basic support for help topics and a dates topic
r3795
Martin Geisler
help: move help topics from mercurial/help.py to help/*.txt...
r9539 from i18n import gettext, _
Augie Fackler
cleanup: move stdlib imports to their own import statement...
r20034 import itertools, sys, os
import error
FUJIWARA Katsunori
filemerge: create detail of internal merge tools from documentation string...
r16126 import extensions, revset, fileset, templatekw, templatefilters, filemerge
Olav Reinert
help: move some helper functions to help.py
r16781 import encoding, util, minirst
Dan Villiom Podlaski Christiansen
help: move the majority of the help command to the help module...
r18746 import cmdutil
Cédric Duval
help: adding a new help topic about extensions...
r8863
Augie Fackler
help: exclude deprecated extensions in the disabled part of 'help extensions'
r20582 def listexts(header, exts, indent=1, showdeprecated=False):
Cédric Duval
help: more improvements for the extensions topic...
r8879 '''return a text listing of the given extensions'''
Olav Reinert
help: format extension lists using RST...
r16852 rst = []
if exts:
rst.append('\n%s\n\n' % header)
for name, desc in sorted(exts.iteritems()):
Augie Fackler
help: exclude deprecated extensions in the disabled part of 'help extensions'
r20582 if '(DEPRECATED)' in desc and not showdeprecated:
continue
Olav Reinert
help: format extension lists using RST...
r16852 rst.append('%s:%s: %s\n' % (' ' * indent, name, desc))
return rst
Cédric Duval
help: refactor extensions listing, and show enabled ones in the dedicated topic
r8864
Cédric Duval
help: more improvements for the extensions topic...
r8879 def extshelp():
Olav Reinert
help: format extension lists using RST...
r16852 rst = loaddoc('extensions')().splitlines(True)
Augie Fackler
help: exclude deprecated extensions in the disabled part of 'help extensions'
r20582 rst.extend(listexts(
_('enabled extensions:'), extensions.enabled(), showdeprecated=True))
Olav Reinert
help: format extension lists using RST...
r16852 rst.extend(listexts(_('disabled extensions:'), extensions.disabled()))
doc = ''.join(rst)
Cédric Duval
help: adding a new help topic about extensions...
r8863 return doc
Martin Geisler
i18n: mark help strings for translation...
r7013
Olav Reinert
help: move some helper functions to help.py
r16781 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:
Olav Reinert
minirst: generate tables as a list of joined lines
r16815 rst.append(_("\n[+] marked option can be specified multiple times\n"))
Olav Reinert
help: move some helper functions to help.py
r16781
Olav Reinert
minirst: generate tables as a list of joined lines
r16815 return ''.join(rst)
Olav Reinert
help: move some helper functions to help.py
r16781
FUJIWARA Katsunori
help: indicate help omitting if help document is not fully displayed...
r17837 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)
Augie Fackler
help: introduce topicmatch for finding topics matching a keyword
r16710 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):
Nikolaj Sjujskij
help: fix search with `-k` option in non-ASCII locales...
r16845 return kw in encoding.lower(container) # translated in helptable
Augie Fackler
help: introduce topicmatch for finding topics matching a keyword
r16710 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 = ''
Nikolaj Sjujskij
help: fix search with `-k` option in non-ASCII locales...
r16845 # translate docs *before* searching there
docs = _(getattr(entry[0], '__doc__', None)) or ''
Augie Fackler
help: introduce topicmatch for finding topics matching a keyword
r16710 if kw in cmd or lowercontains(summary) or lowercontains(docs):
Nikolaj Sjujskij
help: fix search with `-k` option in non-ASCII locales...
r16845 doclines = docs.splitlines()
Augie Fackler
help: introduce topicmatch for finding topics matching a keyword
r16710 if doclines:
summary = doclines[0]
cmdname = cmd.split('|')[0].lstrip('^')
results['commands'].append((cmdname, summary))
for name, docs in itertools.chain(
FUJIWARA Katsunori
help: use full name of extensions to look up them for keyword search...
r19769 extensions.enabled(False).iteritems(),
Augie Fackler
help: introduce topicmatch for finding topics matching a keyword
r16710 extensions.disabled().iteritems()):
# extensions.load ignores the UI argument
mod = extensions.load(None, name, '')
FUJIWARA Katsunori
help: use full name of extensions to look up them for keyword search...
r19769 name = name.split('.')[-1]
Augie Fackler
help: introduce topicmatch for finding topics matching a keyword
r16710 if lowercontains(name) or lowercontains(docs):
Nikolaj Sjujskij
help: fix search with `-k` option in non-ASCII locales...
r16845 # extension docs are already translated
results['extensions'].append((name, docs.splitlines()[0]))
Augie Fackler
help: introduce topicmatch for finding topics matching a keyword
r16710 for cmd, entry in getattr(mod, 'cmdtable', {}).iteritems():
Augie Fackler
help: add --keyword (-k) for searching help
r16711 if kw in cmd or (len(entry) > 2 and lowercontains(entry[2])):
Augie Fackler
help: introduce topicmatch for finding topics matching a keyword
r16710 cmdname = cmd.split('|')[0].lstrip('^')
Olav Reinert
help: fix extension commands help in keyword search...
r16942 if entry[0].__doc__:
cmddoc = gettext(entry[0].__doc__).splitlines()[0]
Thomas Arendsen Hein
help: fix 'hg help -k' matching an extension without docs...
r16884 else:
cmddoc = _('(no help text available)')
results['extensioncommands'].append((cmdname, cmddoc))
Augie Fackler
help: introduce topicmatch for finding topics matching a keyword
r16710 return results
Martin Geisler
help: move help topics from mercurial/help.py to help/*.txt...
r9539 def loaddoc(topic):
"""Return a delayed loader for help/topic.txt."""
Matt Mackall
move environment topic
r3798
Martin Geisler
help: move help topics from mercurial/help.py to help/*.txt...
r9539 def loader():
Augie Fackler
windows: check util.mainfrozen() instead of ad-hoc checks everywhere
r14941 if util.mainfrozen():
Martin Geisler
help: move help topics from mercurial/help.py to help/*.txt...
r9539 module = sys.executable
else:
module = __file__
base = os.path.dirname(module)
Dirkjan Ochtman
help: add a topic on git diffs (issue1352)
r7293
Martin Geisler
help: move help topics from mercurial/help.py to help/*.txt...
r9539 for dir in ('.', '..'):
docdir = os.path.join(base, dir, 'help')
if os.path.isdir(docdir):
break
Alexander Solovyov
help: add a topic about some of the templating features
r7677
Martin Geisler
help: move help topics from mercurial/help.py to help/*.txt...
r9539 path = os.path.join(docdir, topic + ".txt")
Dan Villiom Podlaski Christiansen
prevent transient leaks of file handle by using new helper functions...
r14168 doc = gettext(util.readfile(path))
Patrick Mezard
help: add topic rewriting hooks...
r12820 for rewriter in helphooks.get(topic, []):
doc = rewriter(topic, doc)
return doc
Martin Geisler
help: move help topics from mercurial/help.py to help/*.txt...
r9539 return loader
Alexander Solovyov
help: add a topic about some of the templating features
r7677
Yun Lee
help: sort help topics to make the output more readable (issue2751)
r13888 helptable = sorted([
Martin Geisler
help: make "hg help hgrc" an alias for "hg help config"
r12145 (["config", "hgrc"], _("Configuration Files"), loaddoc('config')),
Martin Geisler
help: move help topics from mercurial/help.py to help/*.txt...
r9539 (["dates"], _("Date Formats"), loaddoc('dates')),
(["patterns"], _("File Name Patterns"), loaddoc('patterns')),
Matt Mackall
many, many trivial check-code fixups
r10282 (['environment', 'env'], _('Environment Variables'),
loaddoc('environment')),
Mads Kiilerich
help: use the first topic name from helptable, not the longest alias...
r17322 (['revisions', 'revs'], _('Specifying Single Revisions'),
Matt Mackall
many, many trivial check-code fixups
r10282 loaddoc('revisions')),
Mads Kiilerich
help: use the first topic name from helptable, not the longest alias...
r17322 (['multirevs', 'mrevs'], _('Specifying Multiple Revisions'),
Matt Mackall
many, many trivial check-code fixups
r10282 loaddoc('multirevs')),
Mads Kiilerich
help: use the first topic name from helptable, not the longest alias...
r17322 (['revsets', 'revset'], _("Specifying Revision Sets"), loaddoc('revsets')),
(['filesets', 'fileset'], _("Specifying File Sets"), loaddoc('filesets')),
Martin Geisler
help: move help topics from mercurial/help.py to help/*.txt...
r9539 (['diffs'], _('Diff Formats'), loaddoc('diffs')),
Mads Kiilerich
help: add 'mergetools' alias for the 'merge-tools' help topic...
r17323 (['merge-tools', 'mergetools'], _('Merge Tools'), loaddoc('merge-tools')),
A. S. Budden
help: add reference to template help (issue3413)...
r16568 (['templating', 'templates', 'template', 'style'], _('Template Usage'),
Matt Mackall
many, many trivial check-code fixups
r10282 loaddoc('templates')),
Martin Geisler
help: move help topics from mercurial/help.py to help/*.txt...
r9539 (['urls'], _('URL Paths'), loaddoc('urls')),
Martin Geisler
help: consistently use title capitalization for help topics
r16547 (["extensions"], _("Using Additional Features"), extshelp),
Mads Kiilerich
help: use the first topic name from helptable, not the longest alias...
r17322 (["subrepos", "subrepo"], _("Subrepositories"), loaddoc('subrepos')),
Mads Kiilerich
help: fix helptable indentation
r17321 (["hgweb"], _("Configuring hgweb"), loaddoc('hgweb')),
(["glossary"], _("Glossary"), loaddoc('glossary')),
(["hgignore", "ignore"], _("Syntax for Mercurial Ignore Files"),
loaddoc('hgignore')),
(["phases"], _("Working with Phases"), loaddoc('phases')),
Yun Lee
help: sort help topics to make the output more readable (issue2751)
r13888 ])
Patrick Mezard
help: add topic rewriting hooks...
r12820
# Map topics to lists of callable taking the current topic help and
# returning the updated version
Matt Mackall
help: consolidate topic hooks in help.py...
r14318 helphooks = {}
Patrick Mezard
help: add topic rewriting hooks...
r12820
def addtopichook(topic, rewriter):
helphooks.setdefault(topic, []).append(rewriter)
Patrick Mezard
help: extract items doc generation function
r13593
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()
"Yann E. MORIN"
help: strip doctest from dochelp...
r16250 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))
Patrick Mezard
help: extract items doc generation function
r13593 entries = '\n\n'.join(entries)
return doc.replace(marker, entries)
Matt Mackall
help: consolidate topic hooks in help.py...
r14318
def addtopicsymbols(topic, marker, symbols):
def add(topic, doc):
return makeitemsdoc(topic, doc, marker, symbols)
addtopichook(topic, add)
Matt Mackall
fileset: add a help topic...
r14686 addtopicsymbols('filesets', '.. predicatesmarker', fileset.symbols)
FUJIWARA Katsunori
filemerge: create detail of internal merge tools from documentation string...
r16126 addtopicsymbols('merge-tools', '.. internaltoolsmarker', filemerge.internals)
Matt Mackall
help: consolidate topic hooks in help.py...
r14318 addtopicsymbols('revsets', '.. predicatesmarker', revset.symbols)
epriestley
templatekw/help: document the {parents} keyword...
r17187 addtopicsymbols('templates', '.. keywordsmarker', templatekw.dockeywords)
Matt Mackall
help: consolidate topic hooks in help.py...
r14318 addtopicsymbols('templates', '.. filtersmarker', templatefilters.filters)
Dan Villiom Podlaski Christiansen
help: move the majority of the help command to the help module...
r18746
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', False):
if not unknowncmd:
ui.pushbuffer()
entry[0](ui)
rst.append(ui.popbuffer())
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('\n%s\n\n' % _("options:"))
rst.append(optrst(entry[1], ui.verbose))
if ui.verbose:
rst.append('\n%s\n\n' % _("global options:"))
rst.append(optrst(commands.globalopts, ui.verbose))
if not ui.verbose:
if not full:
rst.append(_('\nuse "hg help %s" to show the full help text\n')
% name)
elif not ui.quiet:
omitted = _('use "hg -v help %s" to show more complete'
' help and the global options') % name
notomitted = _('use "hg -v help %s" to show'
' the global options') % name
indicateomitted(rst, omitted, notomitted)
return rst
def helplist(select=None):
# list of commands
if name == "shortlist":
header = _('basic commands:\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"):
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))
optlist = []
if not ui.quiet:
if ui.verbose:
optlist.append((_("global options:"), commands.globalopts))
if name == 'shortlist':
optlist.append((_('use "hg help" for the full list '
'of commands'), ()))
else:
if name == 'shortlist':
msg = _('use "hg help" for the full list of commands '
'or "hg -v" for details')
elif name and not full:
msg = _('use "hg help %s" to show the full help '
'text') % name
else:
msg = _('use "hg -v help%s" to show builtin aliases and '
'global options') % (name and " " + name or "")
optlist.append((msg, ()))
if optlist:
for title, options in optlist:
rst.append('\n%s\n' % title)
if options:
rst.append('\n%s\n' % optrst(options, ui.verbose))
return rst
def helptopic(name):
for names, header, doc in helptable:
if name in names:
break
else:
raise error.UnknownCommand(name)
Dan Villiom Podlaski Christiansen
help: use a full header for topic titles...
r18748 rst = [minirst.section(header)]
Dan Villiom Podlaski Christiansen
help: move the majority of the help command to the help module...
r18746 # description
if not doc:
rst.append(" %s\n" % _("(no help text available)"))
if util.safehasattr(doc, '__call__'):
rst += [" %s\n" % l for l in doc().splitlines()]
if not ui.verbose:
omitted = (_('use "hg help -v %s" to show more complete help') %
name)
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 = (_('use "hg help -v %s" to show more complete help') %
name)
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')
elif name and name != 'shortlist':
i = None
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)
i = None
break
except error.UnknownCommand, inst:
i = inst
if i:
raise i
else:
# program name
if not ui.quiet:
rst = [_("Mercurial Distributed SCM\n"), '\n']
rst.extend(helplist())
return ''.join(rst)