mercurial/dispatch.py

check-code: catch Python 'is' comparing number or string literals

The Python 'is' operator compares object identity, so it should
definitely not be applied to string or number literals, which Python
implementations are free to represent with a temporary object.

This should catch the following kinds of bogus expressions (examples):

  x is 'foo'     x is not 'foo'
  x is "bar"     x is not "bar"
  x is 42        x is not 42
  x is -36       x is not -36

As originally proposed by Martin Geisler, amended with catching
negative numbers.

# dispatch.py - command dispatching for mercurial
#
# Copyright 2005-2007 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 _
import os, sys, atexit, signal, pdb, socket, errno, shlex, time, traceback, re
import util, commands, hg, fancyopts, extensions, hook, error
import cmdutil, encoding
import ui as uimod

def run():
    "run the command in sys.argv"
    sys.exit(dispatch(sys.argv[1:]))

def dispatch(args):
    "run the command specified in args"
    try:
        u = uimod.ui()
        if '--traceback' in args:
            u.setconfig('ui', 'traceback', 'on')
    except util.Abort, inst:
        sys.stderr.write(_("abort: %s\n") % inst)
        if inst.hint:
            sys.stderr.write(_("(%s)\n") % inst.hint)
        return -1
    except error.ParseError, inst:
        if len(inst.args) > 1:
            sys.stderr.write(_("hg: parse error at %s: %s\n") %
                             (inst.args[1], inst.args[0]))
        else:
            sys.stderr.write(_("hg: parse error: %s\n") % inst.args[0])
        return -1
    return _runcatch(u, args)

def _runcatch(ui, args):
    def catchterm(*args):
        raise error.SignalInterrupt

    try:
        for name in 'SIGBREAK', 'SIGHUP', 'SIGTERM':
            num = getattr(signal, name, None)
            if num:
                signal.signal(num, catchterm)
    except ValueError:
        pass # happens if called in a thread

    try:
        try:
            # enter the debugger before command execution
            if '--debugger' in args:
                ui.warn(_("entering debugger - "
                        "type c to continue starting hg or h for help\n"))
                pdb.set_trace()
            try:
                return _dispatch(ui, args)
            finally:
                ui.flush()
        except:
            # enter the debugger when we hit an exception
            if '--debugger' in args:
                traceback.print_exc()
                pdb.post_mortem(sys.exc_info()[2])
            ui.traceback()
            raise

    # Global exception handling, alphabetically
    # Mercurial-specific first, followed by built-in and library exceptions
    except error.AmbiguousCommand, inst:
        ui.warn(_("hg: command '%s' is ambiguous:\n    %s\n") %
                (inst.args[0], " ".join(inst.args[1])))
    except error.ParseError, inst:
        if len(inst.args) > 1:
            ui.warn(_("hg: parse error at %s: %s\n") %
                             (inst.args[1], inst.args[0]))
        else:
            ui.warn(_("hg: parse error: %s\n") % inst.args[0])
        return -1
    except error.LockHeld, inst:
        if inst.errno == errno.ETIMEDOUT:
            reason = _('timed out waiting for lock held by %s') % inst.locker
        else:
            reason = _('lock held by %s') % inst.locker
        ui.warn(_("abort: %s: %s\n") % (inst.desc or inst.filename, reason))
    except error.LockUnavailable, inst:
        ui.warn(_("abort: could not lock %s: %s\n") %
               (inst.desc or inst.filename, inst.strerror))
    except error.CommandError, inst:
        if inst.args[0]:
            ui.warn(_("hg %s: %s\n") % (inst.args[0], inst.args[1]))
            commands.help_(ui, inst.args[0])
        else:
            ui.warn(_("hg: %s\n") % inst.args[1])
            commands.help_(ui, 'shortlist')
    except error.RepoError, inst:
        ui.warn(_("abort: %s!\n") % inst)
    except error.ResponseError, inst:
        ui.warn(_("abort: %s") % inst.args[0])
        if not isinstance(inst.args[1], basestring):
            ui.warn(" %r\n" % (inst.args[1],))
        elif not inst.args[1]:
            ui.warn(_(" empty string\n"))
        else:
            ui.warn("\n%r\n" % util.ellipsis(inst.args[1]))
    except error.RevlogError, inst:
        ui.warn(_("abort: %s!\n") % inst)
    except error.SignalInterrupt:
        ui.warn(_("killed!\n"))
    except error.UnknownCommand, inst:
        ui.warn(_("hg: unknown command '%s'\n") % inst.args[0])
        try:
            # check if the command is in a disabled extension
            # (but don't check for extensions themselves)
            commands.help_(ui, inst.args[0], unknowncmd=True)
        except error.UnknownCommand:
            commands.help_(ui, 'shortlist')
    except util.Abort, inst:
        ui.warn(_("abort: %s\n") % inst)
        if inst.hint:
            ui.warn(_("(%s)\n") % inst.hint)
    except ImportError, inst:
        ui.warn(_("abort: %s!\n") % inst)
        m = str(inst).split()[-1]
        if m in "mpatch bdiff".split():
            ui.warn(_("(did you forget to compile extensions?)\n"))
        elif m in "zlib".split():
            ui.warn(_("(is your Python install correct?)\n"))
    except IOError, inst:
        if hasattr(inst, "code"):
            ui.warn(_("abort: %s\n") % inst)
        elif hasattr(inst, "reason"):
            try: # usually it is in the form (errno, strerror)
                reason = inst.reason.args[1]
            except: # it might be anything, for example a string
                reason = inst.reason
            ui.warn(_("abort: error: %s\n") % reason)
        elif hasattr(inst, "args") and inst.args[0] == errno.EPIPE:
            if ui.debugflag:
                ui.warn(_("broken pipe\n"))
        elif getattr(inst, "strerror", None):
            if getattr(inst, "filename", None):
                ui.warn(_("abort: %s: %s\n") % (inst.strerror, inst.filename))
            else:
                ui.warn(_("abort: %s\n") % inst.strerror)
        else:
            raise
    except OSError, inst:
        if getattr(inst, "filename", None):
            ui.warn(_("abort: %s: %s\n") % (inst.strerror, inst.filename))
        else:
            ui.warn(_("abort: %s\n") % inst.strerror)
    except KeyboardInterrupt:
        try:
            ui.warn(_("interrupted!\n"))
        except IOError, inst:
            if inst.errno == errno.EPIPE:
                if ui.debugflag:
                    ui.warn(_("\nbroken pipe\n"))
            else:
                raise
    except MemoryError:
        ui.warn(_("abort: out of memory\n"))
    except SystemExit, inst:
        # Commands shouldn't sys.exit directly, but give a return code.
        # Just in case catch this and and pass exit code to caller.
        return inst.code
    except socket.error, inst:
        ui.warn(_("abort: %s\n") % inst.args[-1])
    except:
        ui.warn(_("** unknown exception encountered,"
                  " please report by visiting\n"))
        ui.warn(_("**  http://mercurial.selenic.com/wiki/BugTracker\n"))
        ui.warn(_("** Python %s\n") % sys.version.replace('\n', ''))
        ui.warn(_("** Mercurial Distributed SCM (version %s)\n")
               % util.version())
        ui.warn(_("** Extensions loaded: %s\n")
               % ", ".join([x[0] for x in extensions.extensions()]))
        raise

    return -1

def aliasargs(fn):
    if hasattr(fn, 'args'):
        return fn.args
    return []

class cmdalias(object):
    def __init__(self, name, definition, cmdtable):
        self.name = self.cmd = name
        self.cmdname = ''
        self.definition = definition
        self.args = []
        self.opts = []
        self.help = ''
        self.norepo = True
        self.badalias = False

        try:
            aliases, entry = cmdutil.findcmd(self.name, cmdtable)
            for alias, e in cmdtable.iteritems():
                if e is entry:
                    self.cmd = alias
                    break
            self.shadows = True
        except error.UnknownCommand:
            self.shadows = False

        if not self.definition:
            def fn(ui, *args):
                ui.warn(_("no definition for alias '%s'\n") % self.name)
                return 1
            self.fn = fn
            self.badalias = True

            return

        if self.definition.startswith('!'):
            self.shell = True
            def fn(ui, *args):
                env = {'HG_ARGS': ' '.join((self.name,) + args)}
                def _checkvar(m):
                    if int(m.groups()[0]) <= len(args):
                        return m.group()
                    else:
                        return ''
                cmd = re.sub(r'\$(\d+)', _checkvar, self.definition[1:])
                replace = dict((str(i + 1), arg) for i, arg in enumerate(args))
                replace['0'] = self.name
                replace['@'] = ' '.join(args)
                cmd = util.interpolate(r'\$', replace, cmd)
                return util.system(cmd, environ=env)
            self.fn = fn
            return

        args = shlex.split(self.definition)
        self.cmdname = cmd = args.pop(0)
        args = map(util.expandpath, args)

        for invalidarg in ("--cwd", "-R", "--repository", "--repo"):
            if _earlygetopt([invalidarg], args):
                def fn(ui, *args):
                    ui.warn(_("error in definition for alias '%s': %s may only "
                              "be given on the command line\n")
                            % (self.name, invalidarg))
                    return 1

                self.fn = fn
                self.badalias = True
                return

        try:
            tableentry = cmdutil.findcmd(cmd, cmdtable, False)[1]
            if len(tableentry) > 2:
                self.fn, self.opts, self.help = tableentry
            else:
                self.fn, self.opts = tableentry

            self.args = aliasargs(self.fn) + args
            if cmd not in commands.norepo.split(' '):
                self.norepo = False
            if self.help.startswith("hg " + cmd):
                # drop prefix in old-style help lines so hg shows the alias
                self.help = self.help[4 + len(cmd):]
            self.__doc__ = self.fn.__doc__

        except error.UnknownCommand:
            def fn(ui, *args):
                ui.warn(_("alias '%s' resolves to unknown command '%s'\n") \
                            % (self.name, cmd))
                try:
                    # check if the command is in a disabled extension
                    commands.help_(ui, cmd, unknowncmd=True)
                except error.UnknownCommand:
                    pass
                return 1
            self.fn = fn
            self.badalias = True
        except error.AmbiguousCommand:
            def fn(ui, *args):
                ui.warn(_("alias '%s' resolves to ambiguous command '%s'\n") \
                            % (self.name, cmd))
                return 1
            self.fn = fn
            self.badalias = True

    def __call__(self, ui, *args, **opts):
        if self.shadows:
            ui.debug("alias '%s' shadows command '%s'\n" %
                     (self.name, self.cmdname))

        if self.definition.startswith('!'):
            return self.fn(ui, *args, **opts)
        else:
            try:
                util.checksignature(self.fn)(ui, *args, **opts)
            except error.SignatureError:
                args = ' '.join([self.cmdname] + self.args)
                ui.debug("alias '%s' expands to '%s'\n" % (self.name, args))
                raise

def addaliases(ui, cmdtable):
    # aliases are processed after extensions have been loaded, so they
    # may use extension commands. Aliases can also use other alias definitions,
    # but only if they have been defined prior to the current definition.
    for alias, definition in ui.configitems('alias'):
        aliasdef = cmdalias(alias, definition, cmdtable)
        cmdtable[aliasdef.cmd] = (aliasdef, aliasdef.opts, aliasdef.help)
        if aliasdef.norepo:
            commands.norepo += ' %s' % alias

def _parse(ui, args):
    options = {}
    cmdoptions = {}

    try:
        args = fancyopts.fancyopts(args, commands.globalopts, options)
    except fancyopts.getopt.GetoptError, inst:
        raise error.CommandError(None, inst)

    if args:
        cmd, args = args[0], args[1:]
        aliases, entry = cmdutil.findcmd(cmd, commands.table,
                                     ui.config("ui", "strict"))
        cmd = aliases[0]
        args = aliasargs(entry[0]) + args
        defaults = ui.config("defaults", cmd)
        if defaults:
            args = map(util.expandpath, shlex.split(defaults)) + args
        c = list(entry[1])
    else:
        cmd = None
        c = []

    # combine global options into local
    for o in commands.globalopts:
        c.append((o[0], o[1], options[o[1]], o[3]))

    try:
        args = fancyopts.fancyopts(args, c, cmdoptions, True)
    except fancyopts.getopt.GetoptError, inst:
        raise error.CommandError(cmd, inst)

    # separate global options back out
    for o in commands.globalopts:
        n = o[1]
        options[n] = cmdoptions[n]
        del cmdoptions[n]

    return (cmd, cmd and entry[0] or None, args, options, cmdoptions)

def _parseconfig(ui, config):
    """parse the --config options from the command line"""
    for cfg in config:
        try:
            name, value = cfg.split('=', 1)
            section, name = name.split('.', 1)
            if not section or not name:
                raise IndexError
            ui.setconfig(section, name, value)
        except (IndexError, ValueError):
            raise util.Abort(_('malformed --config option: %r '
                               '(use --config section.name=value)') % cfg)

def _earlygetopt(aliases, args):
    """Return list of values for an option (or aliases).

    The values are listed in the order they appear in args.
    The options and values are removed from args.
    """
    try:
        argcount = args.index("--")
    except ValueError:
        argcount = len(args)
    shortopts = [opt for opt in aliases if len(opt) == 2]
    values = []
    pos = 0
    while pos < argcount:
        if args[pos] in aliases:
            if pos + 1 >= argcount:
                # ignore and let getopt report an error if there is no value
                break
            del args[pos]
            values.append(args.pop(pos))
            argcount -= 2
        elif args[pos][:2] in shortopts:
            # short option can have no following space, e.g. hg log -Rfoo
            values.append(args.pop(pos)[2:])
            argcount -= 1
        else:
            pos += 1
    return values

def runcommand(lui, repo, cmd, fullargs, ui, options, d, cmdpats, cmdoptions):
    # run pre-hook, and abort if it fails
    ret = hook.hook(lui, repo, "pre-%s" % cmd, False, args=" ".join(fullargs),
                    pats=cmdpats, opts=cmdoptions)
    if ret:
        return ret
    ret = _runcommand(ui, options, cmd, d)
    # run post-hook, passing command result
    hook.hook(lui, repo, "post-%s" % cmd, False, args=" ".join(fullargs),
              result=ret, pats=cmdpats, opts=cmdoptions)
    return ret

def _getlocal(ui, rpath):
    """Return (path, local ui object) for the given target path.

    Takes paths in [cwd]/.hg/hgrc into account."
    """
    try:
        wd = os.getcwd()
    except OSError, e:
        raise util.Abort(_("error getting current working directory: %s") %
                         e.strerror)
    path = cmdutil.findrepo(wd) or ""
    if not path:
        lui = ui
    else:
        lui = ui.copy()
        lui.readconfig(os.path.join(path, ".hg", "hgrc"), path)

    if rpath:
        path = lui.expandpath(rpath[-1])
        lui = ui.copy()
        lui.readconfig(os.path.join(path, ".hg", "hgrc"), path)

    return path, lui

def _checkshellalias(ui, args):
    cwd = os.getcwd()
    norepo = commands.norepo
    options = {}

    try:
        args = fancyopts.fancyopts(args, commands.globalopts, options)
    except fancyopts.getopt.GetoptError:
        return

    if not args:
        return

    _parseconfig(ui, options['config'])
    if options['cwd']:
        os.chdir(options['cwd'])

    path, lui = _getlocal(ui, [options['repository']])

    cmdtable = commands.table.copy()
    addaliases(lui, cmdtable)

    cmd = args[0]
    try:
        aliases, entry = cmdutil.findcmd(cmd, cmdtable, lui.config("ui", "strict"))
    except (error.AmbiguousCommand, error.UnknownCommand):
        commands.norepo = norepo
        os.chdir(cwd)
        return

    cmd = aliases[0]
    fn = entry[0]

    if cmd and hasattr(fn, 'shell'):
        d = lambda: fn(ui, *args[1:])
        return lambda: runcommand(lui, None, cmd, args[:1], ui, options, d, [], {})

    commands.norepo = norepo
    os.chdir(cwd)

_loaded = set()
def _dispatch(ui, args):
    shellaliasfn = _checkshellalias(ui, args)
    if shellaliasfn:
        return shellaliasfn()

    # read --config before doing anything else
    # (e.g. to change trust settings for reading .hg/hgrc)
    _parseconfig(ui, _earlygetopt(['--config'], args))

    # check for cwd
    cwd = _earlygetopt(['--cwd'], args)
    if cwd:
        os.chdir(cwd[-1])

    rpath = _earlygetopt(["-R", "--repository", "--repo"], args)
    path, lui = _getlocal(ui, rpath)

    # Configure extensions in phases: uisetup, extsetup, cmdtable, and
    # reposetup. Programs like TortoiseHg will call _dispatch several
    # times so we keep track of configured extensions in _loaded.
    extensions.loadall(lui)
    exts = [ext for ext in extensions.extensions() if ext[0] not in _loaded]
    # Propagate any changes to lui.__class__ by extensions
    ui.__class__ = lui.__class__

    # (uisetup and extsetup are handled in extensions.loadall)

    for name, module in exts:
        cmdtable = getattr(module, 'cmdtable', {})
        overrides = [cmd for cmd in cmdtable if cmd in commands.table]
        if overrides:
            ui.warn(_("extension '%s' overrides commands: %s\n")
                    % (name, " ".join(overrides)))
        commands.table.update(cmdtable)
        _loaded.add(name)

    # (reposetup is handled in hg.repository)

    addaliases(lui, commands.table)

    # check for fallback encoding
    fallback = lui.config('ui', 'fallbackencoding')
    if fallback:
        encoding.fallbackencoding = fallback

    fullargs = args
    cmd, func, args, options, cmdoptions = _parse(lui, args)

    if options["config"]:
        raise util.Abort(_("option --config may not be abbreviated!"))
    if options["cwd"]:
        raise util.Abort(_("option --cwd may not be abbreviated!"))
    if options["repository"]:
        raise util.Abort(_(
            "Option -R has to be separated from other options (e.g. not -qR) "
            "and --repository may only be abbreviated as --repo!"))

    if options["encoding"]:
        encoding.encoding = options["encoding"]
    if options["encodingmode"]:
        encoding.encodingmode = options["encodingmode"]
    if options["time"]:
        def get_times():
            t = os.times()
            if t[4] == 0.0: # Windows leaves this as zero, so use time.clock()
                t = (t[0], t[1], t[2], t[3], time.clock())
            return t
        s = get_times()
        def print_time():
            t = get_times()
            ui.warn(_("Time: real %.3f secs (user %.3f+%.3f sys %.3f+%.3f)\n") %
                (t[4]-s[4], t[0]-s[0], t[2]-s[2], t[1]-s[1], t[3]-s[3]))
        atexit.register(print_time)

    if options['verbose'] or options['debug'] or options['quiet']:
        ui.setconfig('ui', 'verbose', str(bool(options['verbose'])))
        ui.setconfig('ui', 'debug', str(bool(options['debug'])))
        ui.setconfig('ui', 'quiet', str(bool(options['quiet'])))
    if options['traceback']:
        ui.setconfig('ui', 'traceback', 'on')
    if options['noninteractive']:
        ui.setconfig('ui', 'interactive', 'off')

    if options['help']:
        return commands.help_(ui, cmd, options['version'])
    elif options['version']:
        return commands.version_(ui)
    elif not cmd:
        return commands.help_(ui, 'shortlist')

    repo = None
    cmdpats = args[:]
    if cmd not in commands.norepo.split():
        try:
            repo = hg.repository(ui, path=path)
            ui = repo.ui
            if not repo.local():
                raise util.Abort(_("repository '%s' is not local") % path)
            ui.setconfig("bundle", "mainreporoot", repo.root)
        except error.RepoError:
            if cmd not in commands.optionalrepo.split():
                if args and not path: # try to infer -R from command args
                    repos = map(cmdutil.findrepo, args)
                    guess = repos[0]
                    if guess and repos.count(guess) == len(repos):
                        return _dispatch(ui, ['--repository', guess] + fullargs)
                if not path:
                    raise error.RepoError(_("There is no Mercurial repository"
                                      " here (.hg not found)"))
                raise
        args.insert(0, repo)
    elif rpath:
        ui.warn(_("warning: --repository ignored\n"))

    msg = ' '.join(' ' in a and repr(a) or a for a in fullargs)
    ui.log("command", msg + "\n")
    d = lambda: util.checksignature(func)(ui, *args, **cmdoptions)
    return runcommand(lui, repo, cmd, fullargs, ui, options, d,
                      cmdpats, cmdoptions)

def _runcommand(ui, options, cmd, cmdfunc):
    def checkargs():
        try:
            return cmdfunc()
        except error.SignatureError:
            raise error.CommandError(cmd, _("invalid arguments"))

    if options['profile']:
        format = ui.config('profiling', 'format', default='text')

        if not format in ['text', 'kcachegrind']:
            ui.warn(_("unrecognized profiling format '%s'"
                        " - Ignored\n") % format)
            format = 'text'

        output = ui.config('profiling', 'output')

        if output:
            path = ui.expandpath(output)
            ostream = open(path, 'wb')
        else:
            ostream = sys.stderr

        try:
            from mercurial import lsprof
        except ImportError:
            raise util.Abort(_(
                'lsprof not available - install from '
                'http://codespeak.net/svn/user/arigo/hack/misc/lsprof/'))
        p = lsprof.Profiler()
        p.enable(subcalls=True)
        try:
            return checkargs()
        finally:
            p.disable()

            if format == 'kcachegrind':
                import lsprofcalltree
                calltree = lsprofcalltree.KCacheGrind(p)
                calltree.output(ostream)
            else:
                # format == 'text'
                stats = lsprof.Stats(p.getstats())
                stats.sort()
                stats.pprint(top=10, file=ostream, climit=5)

            if output:
                ostream.close()
    else:
        return checkargs()