~bzr-pqm/bzr/bzr.dev

# Copyright (C) 2006, 2008 Canonical Ltd

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

# TODO: probably should say which arguments are candidates for glob

# expansion on windows and do that at the command level.

# TODO: Define arguments by objects, rather than just using names.

# Those objects can specify the expected type of the argument, which

# would help with validation and shell completion.  They could also provide

# help/explanation for that argument in a structured way.

# TODO: Specific "examples" property on commands for consistent formatting.

# TODO: "--profile=cum", to change sort order.  Is there any value in leaving

# the profile output behind so it can be interactively examined?

import os

import sys

from bzrlib.lazy_import import lazy_import

lazy_import(globals(), """

import codecs

import errno

import threading

from warnings import warn

import bzrlib

from bzrlib import (

    debug,

    errors,

    option,

    osutils,

    trace,

    win32utils,

    )

""")

from bzrlib import registry

# Compatibility

from bzrlib.hooks import HookPoint, Hooks

from bzrlib.option import Option

class CommandInfo(object):

    """Information about a command."""

    def __init__(self, aliases):

        """The list of aliases for the command."""

        self.aliases = aliases

    @classmethod

    def from_command(klass, command):

        """Factory to construct a CommandInfo from a command."""

        return klass(command.aliases)

class CommandRegistry(registry.Registry):

    @staticmethod

    def _get_name(command_name):

        if command_name.startswith("cmd_"):

            return _unsquish_command_name(command_name)

        else:

            return command_name

    def register(self, cmd, decorate=False):

        """Utility function to help register a command

        :param cmd: Command subclass to register

        :param decorate: If true, allow overriding an existing command

            of the same name; the old command is returned by this function.

            Otherwise it is an error to try to override an existing command.

        """

        k = cmd.__name__

        k_unsquished = self._get_name(k)

        try:

            previous = self.get(k_unsquished)

        except KeyError:

            previous = _builtin_commands().get(k_unsquished)

        info = CommandInfo.from_command(cmd)

        try:

            registry.Registry.register(self, k_unsquished, cmd,

                                       override_existing=decorate, info=info)

        except KeyError:

            trace.log_error('Two plugins defined the same command: %r' % k)

            trace.log_error('Not loading the one in %r' %

                            sys.modules[cmd.__module__])

            trace.log_error('Previously this command was registered from %r' %

                            sys.modules[previous.__module__])

        return previous

    def register_lazy(self, command_name, aliases, module_name):

        """Register a command without loading its module.

        :param command_name: The primary name of the command.

        :param aliases: A list of aliases for the command.

        :module_name: The module that the command lives in.

        """

        key = self._get_name(command_name)

        registry.Registry.register_lazy(self, key, module_name, command_name,

                                        info=CommandInfo(aliases))

plugin_cmds = CommandRegistry()

def register_command(cmd, decorate=False):

    global plugin_cmds

    return plugin_cmds.register(cmd, decorate)

def _squish_command_name(cmd):

    return 'cmd_' + cmd.replace('-', '_')

def _unsquish_command_name(cmd):

    return cmd[4:].replace('_','-')

def _builtin_commands():

    import bzrlib.builtins

    r = {}

    builtins = bzrlib.builtins.__dict__

    for name in builtins:

        if name.startswith("cmd_"):

            real_name = _unsquish_command_name(name)

            r[real_name] = builtins[name]

    return r

def builtin_command_names():

    """Return list of builtin command names."""

    return _builtin_commands().keys()

def plugin_command_names():

    return plugin_cmds.keys()

def _get_cmd_dict(plugins_override=True):

    """Return name->class mapping for all commands."""

    d = _builtin_commands()

    if plugins_override:

        d.update(plugin_cmds.iteritems())

    return d

def get_all_cmds(plugins_override=True):

    """Return canonical name and class for all registered commands."""

    for k, v in _get_cmd_dict(plugins_override=plugins_override).iteritems():

        yield k,v

def get_cmd_object(cmd_name, plugins_override=True):

    """Return the canonical name and command class for a command.

    plugins_override

        If true, plugin commands can override builtins.

    """

    try:

        cmd = _get_cmd_object(cmd_name, plugins_override)

        # Allow plugins to extend commands

        for hook in Command.hooks['extend_command']:

            hook(cmd)

        return cmd

    except KeyError:

        raise errors.BzrCommandError('unknown command "%s"' % cmd_name)

def _get_cmd_object(cmd_name, plugins_override=True):

    """Worker for get_cmd_object which raises KeyError rather than BzrCommandError."""

    from bzrlib.externalcommand import ExternalCommand

    # We want only 'ascii' command names, but the user may have typed

    # in a Unicode name. In that case, they should just get a

    # 'command not found' error later.

    # In the future, we may actually support Unicode command names.

    # first look up this command under the specified name

    if plugins_override:

        try:

            return plugin_cmds.get(cmd_name)()

        except KeyError:

            pass

    cmds = _get_cmd_dict(plugins_override=False)

    try:

        return cmds[cmd_name]()

    except KeyError:

        pass

    if plugins_override:

        for key in plugin_cmds.keys():

            info = plugin_cmds.get_info(key)

            if cmd_name in info.aliases:

                return plugin_cmds.get(key)()

    # look for any command which claims this as an alias

    for real_cmd_name, cmd_class in cmds.iteritems():

        if cmd_name in cmd_class.aliases:

            return cmd_class()

    cmd_obj = ExternalCommand.find_command(cmd_name)

    if cmd_obj:

        return cmd_obj

    # look for plugins that provide this command but aren't installed

    for provider in command_providers_registry:

        try:

            plugin_metadata = provider.plugin_for_command(cmd_name)

        except errors.NoPluginAvailable:

            pass

        else:

            raise errors.CommandAvailableInPlugin(cmd_name,

                                                  plugin_metadata, provider)

    raise KeyError

class Command(object):

    """Base class for commands.

    Commands are the heart of the command-line bzr interface.

    The command object mostly handles the mapping of command-line

    parameters into one or more bzrlib operations, and of the results

    into textual output.

    Commands normally don't have any state.  All their arguments are

    passed in to the run method.  (Subclasses may take a different

    policy if the behaviour of the instance needs to depend on e.g. a

    shell plugin and not just its Python class.)

    The docstring for an actual command should give a single-line

    summary, then a complete description of the command.  A grammar

    description will be inserted.

    aliases

        Other accepted names for this command.

    takes_args

        List of argument forms, marked with whether they are optional,

        repeated, etc.

                Examples:

                ['to_location', 'from_branch?', 'file*']

                'to_location' is required

                'from_branch' is optional

                'file' can be specified 0 or more times

    takes_options

        List of options that may be given for this command.  These can

        be either strings, referring to globally-defined options,

        or option objects.  Retrieve through options().

    hidden

        If true, this command isn't advertised.  This is typically

        for commands intended for expert users.

    encoding_type

        Command objects will get a 'outf' attribute, which has been

        setup to properly handle encoding of unicode strings.

        encoding_type determines what will happen when characters cannot

        be encoded

            strict - abort if we cannot decode

            replace - put in a bogus character (typically '?')

            exact - do not encode sys.stdout

            NOTE: by default on Windows, sys.stdout is opened as a text

            stream, therefore LF line-endings are converted to CRLF.

            When a command uses encoding_type = 'exact', then

            sys.stdout is forced to be a binary stream, and line-endings

            will not mangled.

    :cvar hooks: An instance of CommandHooks.

    """

    aliases = []

    takes_args = []

    takes_options = []

    encoding_type = 'strict'

    hidden = False

    def __init__(self):

        """Construct an instance of this command."""

        if self.__doc__ == Command.__doc__:

            warn("No help message set for %r" % self)

        # List of standard options directly supported

        self.supported_std_options = []

    def _maybe_expand_globs(self, file_list):

        """Glob expand file_list if the platform does not do that itself.

        :return: A possibly empty list of unicode paths.

        Introduced in bzrlib 0.18.

        """

        if not file_list:

            file_list = []

        if sys.platform == 'win32':

            file_list = win32utils.glob_expand(file_list)

        return list(file_list)

    def _usage(self):

        """Return single-line grammar for this command.

        Only describes arguments, not options.

        """

        s = 'bzr ' + self.name() + ' '

        for aname in self.takes_args:

            aname = aname.upper()

            if aname[-1] in ['$', '+']:

                aname = aname[:-1] + '...'

            elif aname[-1] == '?':

                aname = '[' + aname[:-1] + ']'

            elif aname[-1] == '*':

                aname = '[' + aname[:-1] + '...]'

            s += aname + ' '

        s = s[:-1]      # remove last space

        return s

    def get_help_text(self, additional_see_also=None, plain=True,

                      see_also_as_links=False, verbose=True):

        """Return a text string with help for this command.

        :param additional_see_also: Additional help topics to be

            cross-referenced.

        :param plain: if False, raw help (reStructuredText) is

            returned instead of plain text.

        :param see_also_as_links: if True, convert items in 'See also'

            list to internal links (used by bzr_man rstx generator)

        :param verbose: if True, display the full help, otherwise

            leave out the descriptive sections and just display

            usage help (e.g. Purpose, Usage, Options) with a

            message explaining how to obtain full help.

        """

        doc = self.help()

        if doc is None:

            raise NotImplementedError("sorry, no detailed help yet for %r" % self.name())

        # Extract the summary (purpose) and sections out from the text

        purpose,sections,order = self._get_help_parts(doc)

        # If a custom usage section was provided, use it

        if sections.has_key('Usage'):

            usage = sections.pop('Usage')

        else:

            usage = self._usage()

        # The header is the purpose and usage

        result = ""

        result += ':Purpose: %s\n' % purpose

        if usage.find('\n') >= 0:

            result += ':Usage:\n%s\n' % usage

        else:

            result += ':Usage:   %s\n' % usage

        result += '\n'

        # Add the options

        options = option.get_optparser(self.options()).format_option_help()

        if options.startswith('Options:'):

            result += ':' + options

        elif options.startswith('options:'):

            # Python 2.4 version of optparse

            result += ':Options:' + options[len('options:'):]

        else:

            result += options

        result += '\n'

        if verbose:

            # Add the description, indenting it 2 spaces

            # to match the indentation of the options

            if sections.has_key(None):

                text = sections.pop(None)

                text = '\n  '.join(text.splitlines())

                result += ':%s:\n  %s\n\n' % ('Description',text)

            # Add the custom sections (e.g. Examples). Note that there's no need

            # to indent these as they must be indented already in the source.

            if sections:

                for label in order:

                    if sections.has_key(label):

                        result += ':%s:\n%s\n' % (label,sections[label])

                result += '\n'

        else:

            result += ("See bzr help %s for more details and examples.\n\n"

                % self.name())

        # Add the aliases, source (plug-in) and see also links, if any

        if self.aliases:

            result += ':Aliases:  '

            result += ', '.join(self.aliases) + '\n'

        plugin_name = self.plugin_name()

        if plugin_name is not None:

            result += ':From:     plugin "%s"\n' % plugin_name

        see_also = self.get_see_also(additional_see_also)

        if see_also:

            if not plain and see_also_as_links:

                see_also_links = []

                for item in see_also:

                    if item == 'topics':

                        # topics doesn't have an independent section

                        # so don't create a real link

                        see_also_links.append(item)

                    else:

                        # Use a reST link for this entry

                        see_also_links.append("`%s`_" % (item,))

                see_also = see_also_links

            result += ':See also: '

            result += ', '.join(see_also) + '\n'

        # If this will be rendered as plain text, convert it

        if plain:

            import bzrlib.help_topics

            result = bzrlib.help_topics.help_as_plain_text(result)

        return result

    @staticmethod

    def _get_help_parts(text):

        """Split help text into a summary and named sections.

        :return: (summary,sections,order) where summary is the top line and

            sections is a dictionary of the rest indexed by section name.

            order is the order the section appear in the text.

            A section starts with a heading line of the form ":xxx:".

            Indented text on following lines is the section value.

            All text found outside a named section is assigned to the

            default section which is given the key of None.

        """

        def save_section(sections, order, label, section):

            if len(section) > 0:

                if sections.has_key(label):

                    sections[label] += '\n' + section

                else:

                    order.append(label)

                    sections[label] = section

        lines = text.rstrip().splitlines()

        summary = lines.pop(0)

        sections = {}

        order = []

        label,section = None,''

        for line in lines:

            if line.startswith(':') and line.endswith(':') and len(line) > 2:

                save_section(sections, order, label, section)

                label,section = line[1:-1],''

            elif (label is not None) and len(line) > 1 and not line[0].isspace():

                save_section(sections, order, label, section)

                label,section = None,line

            else:

                if len(section) > 0:

                    section += '\n' + line

                else:

                    section = line

        save_section(sections, order, label, section)

        return summary, sections, order

    def get_help_topic(self):

        """Return the commands help topic - its name."""

        return self.name()

    def get_see_also(self, additional_terms=None):

        """Return a list of help topics that are related to this command.

        The list is derived from the content of the _see_also attribute. Any

        duplicates are removed and the result is in lexical order.

        :param additional_terms: Additional help topics to cross-reference.

        :return: A list of help topics.

        """

        see_also = set(getattr(self, '_see_also', []))

        if additional_terms:

            see_also.update(additional_terms)

        return sorted(see_also)

    def options(self):

        """Return dict of valid options for this command.

        Maps from long option name to option object."""

        r = Option.STD_OPTIONS.copy()

        std_names = r.keys()

        for o in self.takes_options:

            if isinstance(o, basestring):

                o = option.Option.OPTIONS[o]

            r[o.name] = o

            if o.name in std_names:

                self.supported_std_options.append(o.name)

        return r

    def _setup_outf(self):

        """Return a file linked to stdout, which has proper encoding."""

        # Originally I was using self.stdout, but that looks

        # *way* too much like sys.stdout

        if self.encoding_type == 'exact':

            # force sys.stdout to be binary stream on win32

            if sys.platform == 'win32':

                fileno = getattr(sys.stdout, 'fileno', None)

                if fileno:

                    import msvcrt

                    msvcrt.setmode(fileno(), os.O_BINARY)

            self.outf = sys.stdout

            return

        output_encoding = osutils.get_terminal_encoding()

        self.outf = codecs.getwriter(output_encoding)(sys.stdout,

                        errors=self.encoding_type)

        # For whatever reason codecs.getwriter() does not advertise its encoding

        # it just returns the encoding of the wrapped file, which is completely

        # bogus. So set the attribute, so we can find the correct encoding later.

        self.outf.encoding = output_encoding

    def run_argv_aliases(self, argv, alias_argv=None):

        """Parse the command line and run with extra aliases in alias_argv."""

        if argv is None:

            warn("Passing None for [] is deprecated from bzrlib 0.10",

                 DeprecationWarning, stacklevel=2)

            argv = []

        args, opts = parse_args(self, argv, alias_argv)

        # Process the standard options

        if 'help' in opts:  # e.g. bzr add --help

            sys.stdout.write(self.get_help_text())

            return 0

        if 'usage' in opts:  # e.g. bzr add --usage

            sys.stdout.write(self.get_help_text(verbose=False))

            return 0

        trace.set_verbosity_level(option._verbosity_level)

        if 'verbose' in self.supported_std_options:

            opts['verbose'] = trace.is_verbose()

        elif opts.has_key('verbose'):

            del opts['verbose']

        if 'quiet' in self.supported_std_options:

            opts['quiet'] = trace.is_quiet()

        elif opts.has_key('quiet'):

            del opts['quiet']

        # mix arguments and options into one dictionary

        cmdargs = _match_argform(self.name(), self.takes_args, args)

        cmdopts = {}

        for k, v in opts.items():

            cmdopts[k.replace('-', '_')] = v

        all_cmd_args = cmdargs.copy()

        all_cmd_args.update(cmdopts)

        self._setup_outf()

        return self.run(**all_cmd_args)

    def run(self):

        """Actually run the command.

        This is invoked with the options and arguments bound to

        keyword parameters.

        Return 0 or None if the command was successful, or a non-zero

        shell error code if not.  It's OK for this method to allow

        an exception to raise up.

        """

        raise NotImplementedError('no implementation of command %r'

                                  % self.name())

    def help(self):

        """Return help message for this class."""

        from inspect import getdoc

        if self.__doc__ is Command.__doc__:

            return None

        return getdoc(self)

    def name(self):

        return _unsquish_command_name(self.__class__.__name__)

    def plugin_name(self):

        """Get the name of the plugin that provides this command.

        :return: The name of the plugin or None if the command is builtin.

        """

        mod_parts = self.__module__.split('.')

        if len(mod_parts) >= 3 and mod_parts[1] == 'plugins':

            return mod_parts[2]

        else:

            return None

class CommandHooks(Hooks):

    """Hooks related to Command object creation/enumeration."""

    def __init__(self):

        """Create the default hooks.

        These are all empty initially, because by default nothing should get

        notified.

        """

        Hooks.__init__(self)

        self.create_hook(HookPoint('extend_command',

            "Called after creating a command object to allow modifications "

            "such as adding or removing options, docs etc. Called with the "

            "new bzrlib.commands.Command object.", (1, 13), None))

Command.hooks = CommandHooks()

def parse_args(command, argv, alias_argv=None):

    """Parse command line.

    Arguments and options are parsed at this level before being passed

    down to specific command handlers.  This routine knows, from a

    lookup table, something about the available options, what optargs

    they take, and which commands will accept them.

    """

    # TODO: make it a method of the Command?

    parser = option.get_optparser(command.options())

    if alias_argv is not None:

        args = alias_argv + argv

    else:

        args = argv

    options, args = parser.parse_args(args)

    opts = dict([(k, v) for k, v in options.__dict__.iteritems() if

                 v is not option.OptionParser.DEFAULT_VALUE])

    return args, opts

def _match_argform(cmd, takes_args, args):

    argdict = {}

    # step through args and takes_args, allowing appropriate 0-many matches

    for ap in takes_args:

        argname = ap[:-1]

        if ap[-1] == '?':

            if args:

                argdict[argname] = args.pop(0)

        elif ap[-1] == '*': # all remaining arguments

            if args:

                argdict[argname + '_list'] = args[:]

                args = []

            else:

                argdict[argname + '_list'] = None

        elif ap[-1] == '+':

            if not args:

                raise errors.BzrCommandError("command %r needs one or more %s"

                                             % (cmd, argname.upper()))

            else:

                argdict[argname + '_list'] = args[:]

                args = []

        elif ap[-1] == '$': # all but one

            if len(args) < 2:

                raise errors.BzrCommandError("command %r needs one or more %s"

                                             % (cmd, argname.upper()))

            argdict[argname + '_list'] = args[:-1]

            args[:-1] = []

        else:

            # just a plain arg

            argname = ap

            if not args:

                raise errors.BzrCommandError("command %r requires argument %s"

                               % (cmd, argname.upper()))

            else:

                argdict[argname] = args.pop(0)

    if args:

        raise errors.BzrCommandError("extra argument to command %s: %s"

                                     % (cmd, args[0]))

    return argdict

def apply_coveraged(dirname, the_callable, *args, **kwargs):

    # Cannot use "import trace", as that would import bzrlib.trace instead of

    # the standard library's trace.

    trace = __import__('trace')

    tracer = trace.Trace(count=1, trace=0)