1 files changed, 1586 insertions, 0 deletions

diff --git a/scripts/lib/wic/utils/cmdln.py b/scripts/lib/wic/utils/cmdln.py
new file mode 100644
index 0000000000..b099473ee4
--- /dev/null
+++ b/scripts/lib/wic/utils/cmdln.py
@@ -0,0 +1,1586 @@
+#!/usr/bin/env python
+# Copyright (c) 2002-2007 ActiveState Software Inc.
+# License: MIT (see LICENSE.txt for license details)
+# Author:  Trent Mick
+# Home:    http://trentm.com/projects/cmdln/
+
+"""An improvement on Python's standard cmd.py module.
+
+As with cmd.py, this module provides "a simple framework for writing
+line-oriented command intepreters."  This module provides a 'RawCmdln'
+class that fixes some design flaws in cmd.Cmd, making it more scalable
+and nicer to use for good 'cvs'- or 'svn'-style command line interfaces
+or simple shells.  And it provides a 'Cmdln' class that add
+optparse-based option processing. Basically you use it like this:
+
+    import cmdln
+
+    class MySVN(cmdln.Cmdln):
+        name = "svn"
+
+        @cmdln.alias('stat', 'st')
+        @cmdln.option('-v', '--verbose', action='store_true'
+                      help='print verbose information')
+        def do_status(self, subcmd, opts, *paths):
+            print "handle 'svn status' command"
+
+        #...
+
+    if __name__ == "__main__":
+        shell = MySVN()
+        retval = shell.main()
+        sys.exit(retval)
+
+See the README.txt or <http://trentm.com/projects/cmdln/> for more
+details.
+"""
+
+__version_info__ = (1, 1, 2)
+__version__ = '.'.join(map(str, __version_info__))
+
+import os
+import sys
+import re
+import cmd
+import optparse
+from pprint import pprint
+import sys
+
+
+
+
+#---- globals
+
+LOOP_ALWAYS, LOOP_NEVER, LOOP_IF_EMPTY = range(3)
+
+# An unspecified optional argument when None is a meaningful value.
+_NOT_SPECIFIED = ("Not", "Specified")
+
+# Pattern to match a TypeError message from a call that
+# failed because of incorrect number of arguments (see
+# Python/getargs.c).
+_INCORRECT_NUM_ARGS_RE = re.compile(
+    r"(takes [\w ]+ )(\d+)( arguments? \()(\d+)( given\))")
+
+
+
+#---- exceptions
+
+class CmdlnError(Exception):
+    """A cmdln.py usage error."""
+    def __init__(self, msg):
+        self.msg = msg
+    def __str__(self):
+        return self.msg
+
+class CmdlnUserError(Exception):
+    """An error by a user of a cmdln-based tool/shell."""
+    pass
+
+
+
+#---- public methods and classes
+
+def alias(*aliases):
+    """Decorator to add aliases for Cmdln.do_* command handlers.
+    
+    Example:
+        class MyShell(cmdln.Cmdln):
+            @cmdln.alias("!", "sh")
+            def do_shell(self, argv):
+                #...implement 'shell' command
+    """
+    def decorate(f):
+        if not hasattr(f, "aliases"):
+            f.aliases = []
+        f.aliases += aliases
+        return f
+    return decorate
+
+
+class RawCmdln(cmd.Cmd):
+    """An improved (on cmd.Cmd) framework for building multi-subcommand
+    scripts (think "svn" & "cvs") and simple shells (think "pdb" and
+    "gdb").
+
+    A simple example:
+
+        import cmdln
+
+        class MySVN(cmdln.RawCmdln):
+            name = "svn"
+
+            @cmdln.aliases('stat', 'st')
+            def do_status(self, argv):
+                print "handle 'svn status' command"
+
+        if __name__ == "__main__":
+            shell = MySVN()
+            retval = shell.main()
+            sys.exit(retval)
+
+    See <http://trentm.com/projects/cmdln> for more information.
+    """
+    name = None      # if unset, defaults basename(sys.argv[0])
+    prompt = None    # if unset, defaults to self.name+"> "
+    version = None   # if set, default top-level options include --version
+
+    # Default messages for some 'help' command error cases.
+    # They are interpolated with one arg: the command.
+    nohelp = "no help on '%s'"
+    unknowncmd = "unknown command: '%s'"
+
+    helpindent = '' # string with which to indent help output
+
+    def __init__(self, completekey='tab', 
+                 stdin=None, stdout=None, stderr=None):
+        """Cmdln(completekey='tab', stdin=None, stdout=None, stderr=None)
+
+        The optional argument 'completekey' is the readline name of a
+        completion key; it defaults to the Tab key. If completekey is
+        not None and the readline module is available, command completion
+        is done automatically.
+        
+        The optional arguments 'stdin', 'stdout' and 'stderr' specify
+        alternate input, output and error output file objects; if not
+        specified, sys.* are used.
+        
+        If 'stdout' but not 'stderr' is specified, stdout is used for
+        error output. This is to provide least surprise for users used
+        to only the 'stdin' and 'stdout' options with cmd.Cmd.
+        """
+        import sys
+        if self.name is None:
+            self.name = os.path.basename(sys.argv[0])
+        if self.prompt is None:
+            self.prompt = self.name+"> "
+        self._name_str = self._str(self.name)
+        self._prompt_str = self._str(self.prompt)
+        if stdin is not None:
+            self.stdin = stdin
+        else:
+            self.stdin = sys.stdin
+        if stdout is not None:
+            self.stdout = stdout
+        else:
+            self.stdout = sys.stdout
+        if stderr is not None:
+            self.stderr = stderr
+        elif stdout is not None:
+            self.stderr = stdout
+        else:
+            self.stderr = sys.stderr
+        self.cmdqueue = []
+        self.completekey = completekey
+        self.cmdlooping = False
+
+    def get_optparser(self):
+        """Hook for subclasses to set the option parser for the
+        top-level command/shell.
+
+        This option parser is used retrieved and used by `.main()' to
+        handle top-level options.
+
+        The default implements a single '-h|--help' option. Sub-classes
+        can return None to have no options at the top-level. Typically
+        an instance of CmdlnOptionParser should be returned.
+        """
+        version = (self.version is not None 
+                    and "%s %s" % (self._name_str, self.version)
+                    or None)
+        return CmdlnOptionParser(self, version=version)
+
+    def postoptparse(self):
+        """Hook method executed just after `.main()' parses top-level
+        options.
+
+        When called `self.options' holds the results of the option parse.
+        """
+        pass
+
+    def main(self, argv=None, loop=LOOP_NEVER):
+        """A possible mainline handler for a script, like so:
+
+            import cmdln
+            class MyCmd(cmdln.Cmdln):
+                name = "mycmd"
+                ...
+            
+            if __name__ == "__main__":
+                MyCmd().main()
+
+        By default this will use sys.argv to issue a single command to
+        'MyCmd', then exit. The 'loop' argument can be use to control
+        interactive shell behaviour.
+        
+        Arguments:
+            "argv" (optional, default sys.argv) is the command to run.
+                It must be a sequence, where the first element is the
+                command name and subsequent elements the args for that
+                command.
+            "loop" (optional, default LOOP_NEVER) is a constant
+                indicating if a command loop should be started (i.e. an
+                interactive shell). Valid values (constants on this module):
+                    LOOP_ALWAYS     start loop and run "argv", if any
+                    LOOP_NEVER      run "argv" (or .emptyline()) and exit
+                    LOOP_IF_EMPTY   run "argv", if given, and exit;
+                                    otherwise, start loop
+        """
+        if argv is None:
+            import sys
+            argv = sys.argv
+        else:
+            argv = argv[:] # don't modify caller's list
+
+        self.optparser = self.get_optparser()
+        if self.optparser: # i.e. optparser=None means don't process for opts
+            try:
+                self.options, args = self.optparser.parse_args(argv[1:])
+            except CmdlnUserError, ex:
+                msg = "%s: %s\nTry '%s help' for info.\n"\
+                      % (self.name, ex, self.name)
+                self.stderr.write(self._str(msg))
+                self.stderr.flush()
+                return 1
+            except StopOptionProcessing, ex:
+                return 0
+        else:
+            self.options, args = None, argv[1:]
+        self.postoptparse()
+
+        if loop == LOOP_ALWAYS:
+            if args:
+                self.cmdqueue.append(args)
+            return self.cmdloop()
+        elif loop == LOOP_NEVER:
+            if args:
+                return self.cmd(args)
+            else:
+                return self.emptyline()
+        elif loop == LOOP_IF_EMPTY:
+            if args:
+                return self.cmd(args)
+            else:
+                return self.cmdloop()
+
+    def cmd(self, argv):
+        """Run one command and exit.
+        
+            "argv" is the arglist for the command to run. argv[0] is the
+                command to run. If argv is an empty list then the
+                'emptyline' handler is run.
+
+        Returns the return value from the command handler.
+        """
+        assert isinstance(argv, (list, tuple)), \
+                "'argv' is not a sequence: %r" % argv
+        retval = None
+        try:
+            argv = self.precmd(argv)
+            retval = self.onecmd(argv)
+            self.postcmd(argv)
+        except:
+            if not self.cmdexc(argv):
+                raise
+            retval = 1
+        return retval
+
+    def _str(self, s):
+        """Safely convert the given str/unicode to a string for printing."""
+        try:
+            return str(s)
+        except UnicodeError:
+            #XXX What is the proper encoding to use here? 'utf-8' seems
+            #    to work better than "getdefaultencoding" (usually
+            #    'ascii'), on OS X at least.
+            #import sys
+            #return s.encode(sys.getdefaultencoding(), "replace")
+            return s.encode("utf-8", "replace")
+
+    def cmdloop(self, intro=None):
+        """Repeatedly issue a prompt, accept input, parse into an argv, and
+        dispatch (via .precmd(), .onecmd() and .postcmd()), passing them
+        the argv. In other words, start a shell.
+        
+            "intro" (optional) is a introductory message to print when
+                starting the command loop. This overrides the class
+                "intro" attribute, if any.
+        """
+        self.cmdlooping = True
+        self.preloop()
+        if self.use_rawinput and self.completekey:
+            try:
+                import readline
+                self.old_completer = readline.get_completer()
+                readline.set_completer(self.complete)
+                readline.parse_and_bind(self.completekey+": complete")
+            except ImportError:
+                pass
+        try:
+            if intro is None:
+                intro = self.intro
+            if intro:
+                intro_str = self._str(intro)
+                self.stdout.write(intro_str+'\n')
+            self.stop = False
+            retval = None
+            while not self.stop:
+                if self.cmdqueue:
+                    argv = self.cmdqueue.pop(0)
+                    assert isinstance(argv, (list, tuple)), \
+                            "item on 'cmdqueue' is not a sequence: %r" % argv
+                else:
+                    if self.use_rawinput:
+                        try:
+                            line = raw_input(self._prompt_str)
+                        except EOFError:
+                            line = 'EOF'
+                    else:
+                        self.stdout.write(self._prompt_str)
+                        self.stdout.flush()
+                        line = self.stdin.readline()
+                        if not len(line):
+                            line = 'EOF'
+                        else:
+                            line = line[:-1] # chop '\n'
+                    argv = line2argv(line)
+                try:
+                    argv = self.precmd(argv)
+                    retval = self.onecmd(argv)
+                    self.postcmd(argv)
+                except:
+                    if not self.cmdexc(argv):
+                        raise
+                    retval = 1
+                self.lastretval = retval
+            self.postloop()
+        finally:
+            if self.use_rawinput and self.completekey:
+                try:
+                    import readline
+                    readline.set_completer(self.old_completer)
+                except ImportError:
+                    pass
+        self.cmdlooping = False
+        return retval
+
+    def precmd(self, argv):
+        """Hook method executed just before the command argv is
+        interpreted, but after the input prompt is generated and issued.
+
+            "argv" is the cmd to run.
+            
+        Returns an argv to run (i.e. this method can modify the command
+        to run).
+        """
+        return argv
+
+    def postcmd(self, argv):
+        """Hook method executed just after a command dispatch is finished.
+        
+            "argv" is the command that was run.
+        """
+        pass
+
+    def cmdexc(self, argv):
+        """Called if an exception is raised in any of precmd(), onecmd(),
+        or postcmd(). If True is returned, the exception is deemed to have
+        been dealt with. Otherwise, the exception is re-raised.
+
+        The default implementation handles CmdlnUserError's, which
+        typically correspond to user error in calling commands (as
+        opposed to programmer error in the design of the script using
+        cmdln.py).
+        """
+        import sys
+        type, exc, traceback = sys.exc_info()
+        if isinstance(exc, CmdlnUserError):
+            msg = "%s %s: %s\nTry '%s help %s' for info.\n"\
+                  % (self.name, argv[0], exc, self.name, argv[0])
+            self.stderr.write(self._str(msg))
+            self.stderr.flush()
+            return True
+
+    def onecmd(self, argv):
+        if not argv:
+            return self.emptyline()
+        self.lastcmd = argv
+        cmdname = self._get_canonical_cmd_name(argv[0])
+        if cmdname:
+            handler = self._get_cmd_handler(cmdname)
+            if handler:
+                return self._dispatch_cmd(handler, argv)
+        return self.default(argv)
+
+    def _dispatch_cmd(self, handler, argv):
+        return handler(argv)
+
+    def default(self, argv):
+        """Hook called to handle a command for which there is no handler.
+
+            "argv" is the command and arguments to run.
+        
+        The default implementation writes and error message to stderr
+        and returns an error exit status.
+
+        Returns a numeric command exit status.
+        """
+        errmsg = self._str(self.unknowncmd % (argv[0],))
+        if self.cmdlooping:
+            self.stderr.write(errmsg+"\n")
+        else:
+            self.stderr.write("%s: %s\nTry '%s help' for info.\n"
+                              % (self._name_str, errmsg, self._name_str))
+        self.stderr.flush()
+        return 1
+
+    def parseline(self, line):
+        # This is used by Cmd.complete (readline completer function) to
+        # massage the current line buffer before completion processing.
+        # We override to drop special '!' handling.
+        line = line.strip()
+        if not line:
+            return None, None, line
+        elif line[0] == '?':
+            line = 'help ' + line[1:]
+        i, n = 0, len(line)
+        while i < n and line[i] in self.identchars: i = i+1
+        cmd, arg = line[:i], line[i:].strip()
+        return cmd, arg, line
+
+    def helpdefault(self, cmd, known):
+        """Hook called to handle help on a command for which there is no
+        help handler.
+
+            "cmd" is the command name on which help was requested.
+            "known" is a boolean indicating if this command is known
+                (i.e. if there is a handler for it).
+        
+        Returns a return code.
+        """
+        if known:
+            msg = self._str(self.nohelp % (cmd,))
+            if self.cmdlooping:
+                self.stderr.write(msg + '\n')
+            else:
+                self.stderr.write("%s: %s\n" % (self.name, msg))
+        else:
+            msg = self.unknowncmd % (cmd,)
+            if self.cmdlooping:
+                self.stderr.write(msg + '\n')
+            else:
+                self.stderr.write("%s: %s\n"
+                                  "Try '%s help' for info.\n"
+                                  % (self.name, msg, self.name))
+        self.stderr.flush()
+        return 1
+
+    def do_help(self, argv):
+        """${cmd_name}: give detailed help on a specific sub-command
+
+        Usage:
+            ${name} help [COMMAND]
+        """
+        if len(argv) > 1: # asking for help on a particular command
+            doc = None
+            cmdname = self._get_canonical_cmd_name(argv[1]) or argv[1]
+            if not cmdname:
+                return self.helpdefault(argv[1], False)
+            else:
+                helpfunc = getattr(self, "help_"+cmdname, None)
+                if helpfunc:
+                    doc = helpfunc()
+                else:
+                    handler = self._get_cmd_handler(cmdname)
+                    if handler:
+                        doc = handler.__doc__
+                    if doc is None:
+                        return self.helpdefault(argv[1], handler != None)
+        else: # bare "help" command
+            doc = self.__class__.__doc__  # try class docstring
+            if doc is None:
+                # Try to provide some reasonable useful default help.
+                if self.cmdlooping: prefix = ""
+                else:               prefix = self.name+' '
+                doc = """Usage:
+                    %sCOMMAND [ARGS...]
+                    %shelp [COMMAND]
+
+                ${option_list}
+                ${command_list}
+                ${help_list}
+                """ % (prefix, prefix)
+            cmdname = None
+
+        if doc: # *do* have help content, massage and print that
+            doc = self._help_reindent(doc)
+            doc = self._help_preprocess(doc, cmdname)
+            doc = doc.rstrip() + '\n' # trim down trailing space
+            self.stdout.write(self._str(doc))
+            self.stdout.flush()
+    do_help.aliases = ["?"]
+
+    def _help_reindent(self, help, indent=None):
+        """Hook to re-indent help strings before writing to stdout.
+
+            "help" is the help content to re-indent
+            "indent" is a string with which to indent each line of the
+                help content after normalizing. If unspecified or None
+                then the default is use: the 'self.helpindent' class
+                attribute. By default this is the empty string, i.e.
+                no indentation.
+
+        By default, all common leading whitespace is removed and then
+        the lot is indented by 'self.helpindent'. When calculating the
+        common leading whitespace the first line is ignored -- hence
+        help content for Conan can be written as follows and have the
+        expected indentation:
+
+            def do_crush(self, ...):
+                '''${cmd_name}: crush your enemies, see them driven before you...
+
+                c.f. Conan the Barbarian'''
+        """
+        if indent is None:
+            indent = self.helpindent
+        lines = help.splitlines(0)
+        _dedentlines(lines, skip_first_line=True)
+        lines = [(indent+line).rstrip() for line in lines]
+        return '\n'.join(lines)
+
+    def _help_preprocess(self, help, cmdname):
+        """Hook to preprocess a help string before writing to stdout.
+
+            "help" is the help string to process.
+            "cmdname" is the canonical sub-command name for which help
+                is being given, or None if the help is not specific to a
+                command.
+
+        By default the following template variables are interpolated in
+        help content. (Note: these are similar to Python 2.4's
+        string.Template interpolation but not quite.)
+
+        ${name}
+            The tool's/shell's name, i.e. 'self.name'.
+        ${option_list}
+            A formatted table of options for this shell/tool.
+        ${command_list}
+            A formatted table of available sub-commands.
+        ${help_list}
+            A formatted table of additional help topics (i.e. 'help_*'
+            methods with no matching 'do_*' method).
+        ${cmd_name}
+            The name (and aliases) for this sub-command formatted as:
+            "NAME (ALIAS1, ALIAS2, ...)".
+        ${cmd_usage}
+            A formatted usage block inferred from the command function
+            signature.
+        ${cmd_option_list}
+            A formatted table of options for this sub-command. (This is
+            only available for commands using the optparse integration,
+            i.e.  using @cmdln.option decorators or manually setting the
+            'optparser' attribute on the 'do_*' method.)
+
+        Returns the processed help. 
+        """
+        preprocessors = {
+            "${name}":            self._help_preprocess_name,
+            "${option_list}":     self._help_preprocess_option_list,
+            "${command_list}":    self._help_preprocess_command_list,
+            "${help_list}":       self._help_preprocess_help_list,
+            "${cmd_name}":        self._help_preprocess_cmd_name,
+            "${cmd_usage}":       self._help_preprocess_cmd_usage,
+            "${cmd_option_list}": self._help_preprocess_cmd_option_list,
+        }
+
+        for marker, preprocessor in preprocessors.items():
+            if marker in help:
+                help = preprocessor(help, cmdname)
+        return help
+
+    def _help_preprocess_name(self, help, cmdname=None):
+        return help.replace("${name}", self.name)
+
+    def _help_preprocess_option_list(self, help, cmdname=None):
+        marker = "${option_list}"
+        indent, indent_width = _get_indent(marker, help)
+        suffix = _get_trailing_whitespace(marker, help)
+
+        if self.optparser:
+            # Setup formatting options and format.
+            # - Indentation of 4 is better than optparse default of 2.
+            #   C.f. Damian Conway's discussion of this in Perl Best
+            #   Practices.
+            self.optparser.formatter.indent_increment = 4
+            self.optparser.formatter.current_indent = indent_width
+            block = self.optparser.format_option_help() + '\n'
+        else:
+            block = ""
+            
+        help = help.replace(indent+marker+suffix, block, 1)
+        return help
+
+
+    def _help_preprocess_command_list(self, help, cmdname=None):
+        marker = "${command_list}"
+        indent, indent_width = _get_indent(marker, help)
+        suffix = _get_trailing_whitespace(marker, help)
+
+        # Find any aliases for commands.
+        token2canonical = self._get_canonical_map()
+        aliases = {}
+        for token, cmdname in token2canonical.items():
+            if token == cmdname: continue
+            aliases.setdefault(cmdname, []).append(token)
+
+        # Get the list of (non-hidden) commands and their
+        # documentation, if any.
+        cmdnames = {} # use a dict to strip duplicates
+        for attr in self.get_names():
+            if attr.startswith("do_"):
+                cmdnames[attr[3:]] = True
+        cmdnames = cmdnames.keys()
+        cmdnames.sort()
+        linedata = []
+        for cmdname in cmdnames:
+            if aliases.get(cmdname):
+                a = aliases[cmdname]
+                a.sort()
+                cmdstr = "%s (%s)" % (cmdname, ", ".join(a))
+            else:
+                cmdstr = cmdname
+            doc = None
+            try:
+                helpfunc = getattr(self, 'help_'+cmdname)
+            except AttributeError:
+                handler = self._get_cmd_handler(cmdname)
+                if handler:
+                    doc = handler.__doc__
+            else:
+                doc = helpfunc()
+                
+            # Strip "${cmd_name}: " from the start of a command's doc. Best
+            # practice dictates that command help strings begin with this, but
+            # it isn't at all wanted for the command list.
+            to_strip = "${cmd_name}:"
+            if doc and doc.startswith(to_strip):
+                #log.debug("stripping %r from start of %s's help string",
+                #          to_strip, cmdname)
+                doc = doc[len(to_strip):].lstrip()
+            linedata.append( (cmdstr, doc) )
+
+        if linedata:
+            subindent = indent + ' '*4
+            lines = _format_linedata(linedata, subindent, indent_width+4)
+            block = indent + "Commands:\n" \
+                    + '\n'.join(lines) + "\n\n"
+            help = help.replace(indent+marker+suffix, block, 1)
+        return help
+
+    def _gen_names_and_attrs(self):
+        # Inheritance says we have to look in class and
+        # base classes; order is not important.
+        names = []
+        classes = [self.__class__]
+        while classes:
+            aclass = classes.pop(0)
+            if aclass.__bases__:
+                classes = classes + list(aclass.__bases__)
+            for name in dir(aclass):
+                yield (name, getattr(aclass, name))
+
+    def _help_preprocess_help_list(self, help, cmdname=None):
+        marker = "${help_list}"
+        indent, indent_width = _get_indent(marker, help)
+        suffix = _get_trailing_whitespace(marker, help)
+
+        # Determine the additional help topics, if any.
+        helpnames = {}
+        token2cmdname = self._get_canonical_map()
+        for attrname, attr in self._gen_names_and_attrs():
+            if not attrname.startswith("help_"): continue
+            helpname = attrname[5:]
+            if helpname not in token2cmdname:
+                helpnames[helpname] = attr
+
+        if helpnames:
+            linedata = [(n, a.__doc__ or "") for n, a in helpnames.items()]
+            linedata.sort()
+
+            subindent = indent + ' '*4
+            lines = _format_linedata(linedata, subindent, indent_width+4)
+            block = (indent
+                    + "Additional help topics (run `%s help TOPIC'):\n" % self.name
+                    + '\n'.join(lines)
+                    + "\n\n")
+        else:
+            block = ''
+        help = help.replace(indent+marker+suffix, block, 1)
+        return help
+
+    def _help_preprocess_cmd_name(self, help, cmdname=None):
+        marker = "${cmd_name}"
+        handler = self._get_cmd_handler(cmdname)
+        if not handler:
+            raise CmdlnError("cannot preprocess '%s' into help string: "
+                             "could not find command handler for %r" 
+                             % (marker, cmdname))
+        s = cmdname
+        if hasattr(handler, "aliases"):
+            s += " (%s)" % (", ".join(handler.aliases))
+        help = help.replace(marker, s)
+        return help
+
+    #TODO: this only makes sense as part of the Cmdln class.
+    #      Add hooks to add help preprocessing template vars and put
+    #      this one on that class.
+    def _help_preprocess_cmd_usage(self, help, cmdname=None):
+        marker = "${cmd_usage}"
+        handler = self._get_cmd_handler(cmdname)
+        if not handler:
+            raise CmdlnError("cannot preprocess '%s' into help string: "
+                             "could not find command handler for %r" 
+                             % (marker, cmdname))
+        indent, indent_width = _get_indent(marker, help)
+        suffix = _get_trailing_whitespace(marker, help)
+
+        # Extract the introspection bits we need.
+        func = handler.im_func
+        if func.func_defaults:
+            func_defaults = list(func.func_defaults)
+        else:
+            func_defaults = []
+        co_argcount = func.func_code.co_argcount
+        co_varnames = func.func_code.co_varnames
+        co_flags = func.func_code.co_flags
+        CO_FLAGS_ARGS = 4
+        CO_FLAGS_KWARGS = 8
+
+        # Adjust argcount for possible *args and **kwargs arguments.
+        argcount = co_argcount
+        if co_flags & CO_FLAGS_ARGS:   argcount += 1
+        if co_flags & CO_FLAGS_KWARGS: argcount += 1
+
+        # Determine the usage string.
+        usage = "%s %s" % (self.name, cmdname)
+        if argcount <= 2:   # handler ::= do_FOO(self, argv)
+            usage += " [ARGS...]"
+        elif argcount >= 3: # handler ::= do_FOO(self, subcmd, opts, ...)
+            argnames = list(co_varnames[3:argcount])
+            tail = ""
+            if co_flags & CO_FLAGS_KWARGS:
+                name = argnames.pop(-1)
+                import warnings
+                # There is no generally accepted mechanism for passing
+                # keyword arguments from the command line. Could
+                # *perhaps* consider: arg=value arg2=value2 ...
+                warnings.warn("argument '**%s' on '%s.%s' command "
+                              "handler will never get values" 
+                              % (name, self.__class__.__name__,
+                                 func.func_name))
+            if co_flags & CO_FLAGS_ARGS:
+                name = argnames.pop(-1)
+                tail = "[%s...]" % name.upper()
+            while func_defaults:
+                func_defaults.pop(-1)
+                name = argnames.pop(-1)
+                tail = "[%s%s%s]" % (name.upper(), (tail and ' ' or ''), tail)
+            while argnames:
+                name = argnames.pop(-1)
+                tail = "%s %s" % (name.upper(), tail)
+            usage += ' ' + tail
+
+        block_lines = [
+            self.helpindent + "Usage:",
+            self.helpindent + ' '*4 + usage
+        ]
+        block = '\n'.join(block_lines) + '\n\n'
+
+        help = help.replace(indent+marker+suffix, block, 1)
+        return help
+
+    #TODO: this only makes sense as part of the Cmdln class.
+    #      Add hooks to add help preprocessing template vars and put
+    #      this one on that class.
+    def _help_preprocess_cmd_option_list(self, help, cmdname=None):
+        marker = "${cmd_option_list}"
+        handler = self._get_cmd_handler(cmdname)
+        if not handler:
+            raise CmdlnError("cannot preprocess '%s' into help string: "
+                             "could not find command handler for %r" 
+                             % (marker, cmdname))
+        indent, indent_width = _get_indent(marker, help)
+        suffix = _get_trailing_whitespace(marker, help)
+        if hasattr(handler, "optparser"):
+            # Setup formatting options and format.
+            # - Indentation of 4 is better than optparse default of 2.
+            #   C.f. Damian Conway's discussion of this in Perl Best
+            #   Practices.
+            handler.optparser.formatter.indent_increment = 4
+            handler.optparser.formatter.current_indent = indent_width
+            block = handler.optparser.format_option_help() + '\n'
+        else:
+            block = ""
+
+        help = help.replace(indent+marker+suffix, block, 1)
+        return help
+
+    def _get_canonical_cmd_name(self, token):
+        map = self._get_canonical_map()
+        return map.get(token, None)
+
+    def _get_canonical_map(self):
+        """Return a mapping of available command names and aliases to
+        their canonical command name.
+        """
+        cacheattr = "_token2canonical"
+        if not hasattr(self, cacheattr):
+            # Get the list of commands and their aliases, if any.
+            token2canonical = {}
+            cmd2funcname = {} # use a dict to strip duplicates
+            for attr in self.get_names():
+                if attr.startswith("do_"):    cmdname = attr[3:]
+                elif attr.startswith("_do_"): cmdname = attr[4:]
+                else:
+                    continue
+                cmd2funcname[cmdname] = attr
+                token2canonical[cmdname] = cmdname
+            for cmdname, funcname in cmd2funcname.items(): # add aliases
+                func = getattr(self, funcname)
+                aliases = getattr(func, "aliases", [])
+                for alias in aliases:
+                    if alias in cmd2funcname:
+                        import warnings
+                        warnings.warn("'%s' alias for '%s' command conflicts "
+                                      "with '%s' handler"
+                                      % (alias, cmdname, cmd2funcname[alias]))
+                        continue
+                    token2canonical[alias] = cmdname
+            setattr(self, cacheattr, token2canonical)
+        return getattr(self, cacheattr)
+
+    def _get_cmd_handler(self, cmdname):
+        handler = None
+        try:
+            handler = getattr(self, 'do_' + cmdname)
+        except AttributeError:
+            try:
+                # Private command handlers begin with "_do_".
+                handler = getattr(self, '_do_' + cmdname)
+            except AttributeError:
+                pass
+        return handler
+
+    def _do_EOF(self, argv):
+        # Default EOF handler
+        # Note: an actual EOF is redirected to this command.
+        #TODO: separate name for this. Currently it is available from
+        #      command-line. Is that okay?
+        self.stdout.write('\n')
+        self.stdout.flush()
+        self.stop = True
+
+    def emptyline(self):
+        # Different from cmd.Cmd: don't repeat the last command for an
+        # emptyline.
+        if self.cmdlooping:
+            pass
+        else:
+            return self.do_help(["help"])
+
+
+#---- optparse.py extension to fix (IMO) some deficiencies
+#
+# See the class _OptionParserEx docstring for details.
+#
+
+class StopOptionProcessing(Exception):
+    """Indicate that option *and argument* processing should stop
+    cleanly. This is not an error condition. It is similar in spirit to
+    StopIteration. This is raised by _OptionParserEx's default "help"
+    and "version" option actions and can be raised by custom option
+    callbacks too.
+    
+    Hence the typical CmdlnOptionParser (a subclass of _OptionParserEx)
+    usage is:
+
+        parser = CmdlnOptionParser(mycmd)
+        parser.add_option("-f", "--force", dest="force")
+        ...
+        try:
+            opts, args = parser.parse_args()
+        except StopOptionProcessing:
+            # normal termination, "--help" was probably given
+            sys.exit(0)
+    """
+
+class _OptionParserEx(optparse.OptionParser):
+    """An optparse.OptionParser that uses exceptions instead of sys.exit.
+
+    This class is an extension of optparse.OptionParser that differs
+    as follows:
+    - Correct (IMO) the default OptionParser error handling to never
+      sys.exit(). Instead OptParseError exceptions are passed through.
+    - Add the StopOptionProcessing exception (a la StopIteration) to
+      indicate normal termination of option processing.
+      See StopOptionProcessing's docstring for details.
+
+    I'd also like to see the following in the core optparse.py, perhaps
+    as a RawOptionParser which would serve as a base class for the more
+    generally used OptionParser (that works as current):
+    - Remove the implicit addition of the -h|--help and --version
+      options. They can get in the way (e.g. if want '-?' and '-V' for
+      these as well) and it is not hard to do:
+        optparser.add_option("-h", "--help", action="help")
+        optparser.add_option("--version", action="version")
+      These are good practices, just not valid defaults if they can
+      get in the way.
+    """
+    def error(self, msg):
+        raise optparse.OptParseError(msg)
+
+    def exit(self, status=0, msg=None):
+        if status == 0:
+            raise StopOptionProcessing(msg)
+        else:
+            #TODO: don't lose status info here
+            raise optparse.OptParseError(msg)
+
+
+
+#---- optparse.py-based option processing support
+
+class CmdlnOptionParser(_OptionParserEx):
+    """An optparse.OptionParser class more appropriate for top-level
+    Cmdln options. For parsing of sub-command options, see
+    SubCmdOptionParser.
+
+    Changes:
+    - disable_interspersed_args() by default, because a Cmdln instance
+      has sub-commands which may themselves have options.
+    - Redirect print_help() to the Cmdln.do_help() which is better
+      equiped to handle the "help" action.
+    - error() will raise a CmdlnUserError: OptionParse.error() is meant
+      to be called for user errors. Raising a well-known error here can
+      make error handling clearer.
+    - Also see the changes in _OptionParserEx.
+    """
+    def __init__(self, cmdln, **kwargs):
+        self.cmdln = cmdln
+        kwargs["prog"] = self.cmdln.name
+        _OptionParserEx.__init__(self, **kwargs)
+        self.disable_interspersed_args()
+
+    def print_help(self, file=None):
+        self.cmdln.onecmd(["help"])
+
+    def error(self, msg):
+        raise CmdlnUserError(msg)
+
+
+class SubCmdOptionParser(_OptionParserEx):
+    def set_cmdln_info(self, cmdln, subcmd):
+        """Called by Cmdln to pass relevant info about itself needed
+        for print_help().
+        """
+        self.cmdln = cmdln
+        self.subcmd = subcmd
+
+    def print_help(self, file=None):
+        self.cmdln.onecmd(["help", self.subcmd])
+
+    def error(self, msg):
+        raise CmdlnUserError(msg)
+
+
+def option(*args, **kwargs):
+    """Decorator to add an option to the optparser argument of a Cmdln
+    subcommand.
+    
+    Example:
+        class MyShell(cmdln.Cmdln):
+            @cmdln.option("-f", "--force", help="force removal")
+            def do_remove(self, subcmd, opts, *args):
+                #...
+    """
+    #XXX Is there a possible optimization for many options to not have a
+    #    large stack depth here?
+    def decorate(f):
+        if not hasattr(f, "optparser"):
+            f.optparser = SubCmdOptionParser()
+        f.optparser.add_option(*args, **kwargs)
+        return f
+    return decorate
+
+
+class Cmdln(RawCmdln):
+    """An improved (on cmd.Cmd) framework for building multi-subcommand
+    scripts (think "svn" & "cvs") and simple shells (think "pdb" and
+    "gdb").
+
+    A simple example:
+
+        import cmdln
+
+        class MySVN(cmdln.Cmdln):
+            name = "svn"
+
+            @cmdln.aliases('stat', 'st')
+            @cmdln.option('-v', '--verbose', action='store_true'
+                          help='print verbose information')
+            def do_status(self, subcmd, opts, *paths):
+                print "handle 'svn status' command"
+
+            #...
+
+        if __name__ == "__main__":
+            shell = MySVN()
+            retval = shell.main()
+            sys.exit(retval)
+
+    'Cmdln' extends 'RawCmdln' by providing optparse option processing
+    integration.  See this class' _dispatch_cmd() docstring and
+    <http://trentm.com/projects/cmdln> for more information.
+    """
+    def _dispatch_cmd(self, handler, argv):
+        """Introspect sub-command handler signature to determine how to
+        dispatch the command. The raw handler provided by the base
+        'RawCmdln' class is still supported:
+
+            def do_foo(self, argv):
+                # 'argv' is the vector of command line args, argv[0] is
+                # the command name itself (i.e. "foo" or an alias)
+                pass
+
+        In addition, if the handler has more than 2 arguments option
+        processing is automatically done (using optparse):
+
+            @cmdln.option('-v', '--verbose', action='store_true')
+            def do_bar(self, subcmd, opts, *args):
+                # subcmd = <"bar" or an alias>
+                # opts = <an optparse.Values instance>
+                if opts.verbose:
+                    print "lots of debugging output..."
+                # args = <tuple of arguments>
+                for arg in args:
+                    bar(arg)
+
+        TODO: explain that "*args" can be other signatures as well.
+
+        The `cmdln.option` decorator corresponds to an `add_option()`
+        method call on an `optparse.OptionParser` instance.
+
+        You can declare a specific number of arguments:
+
+            @cmdln.option('-v', '--verbose', action='store_true')
+            def do_bar2(self, subcmd, opts, bar_one, bar_two):
+                #...
+
+        and an appropriate error message will be raised/printed if the
+        command is called with a different number of args.
+        """
+        co_argcount = handler.im_func.func_code.co_argcount
+        if co_argcount == 2:   # handler ::= do_foo(self, argv)
+            return handler(argv)
+        elif co_argcount >= 3: # handler ::= do_foo(self, subcmd, opts, ...)
+            try:
+                optparser = handler.optparser
+            except AttributeError:
+                optparser = handler.im_func.optparser = SubCmdOptionParser()
+            assert isinstance(optparser, SubCmdOptionParser)
+            optparser.set_cmdln_info(self, argv[0])
+            try:
+                opts, args = optparser.parse_args(argv[1:])
+            except StopOptionProcessing:
+                #TODO: this doesn't really fly for a replacement of
+                #      optparse.py behaviour, does it?
+                return 0 # Normal command termination
+
+            try:
+                return handler(argv[0], opts, *args)
+            except TypeError, ex:
+                # Some TypeError's are user errors:
+                #   do_foo() takes at least 4 arguments (3 given)
+                #   do_foo() takes at most 5 arguments (6 given)
+                #   do_foo() takes exactly 5 arguments (6 given)
+                # Raise CmdlnUserError for these with a suitably
+                # massaged error message.
+                import sys
+                tb = sys.exc_info()[2] # the traceback object
+                if tb.tb_next is not None:
+                    # If the traceback is more than one level deep, then the
+                    # TypeError do *not* happen on the "handler(...)" call
+                    # above. In that we don't want to handle it specially
+                    # here: it would falsely mask deeper code errors.
+                    raise
+                msg = ex.args[0]
+                match = _INCORRECT_NUM_ARGS_RE.search(msg)
+                if match:
+                    msg = list(match.groups())
+                    msg[1] = int(msg[1]) - 3
+                    if msg[1] == 1:
+                        msg[2] = msg[2].replace("arguments", "argument")
+                    msg[3] = int(msg[3]) - 3
+                    msg = ''.join(map(str, msg))
+                    raise CmdlnUserError(msg)
+                else:
+                    raise
+        else:
+            raise CmdlnError("incorrect argcount for %s(): takes %d, must "
+                             "take 2 for 'argv' signature or 3+ for 'opts' "
+                             "signature" % (handler.__name__, co_argcount))
+        
+
+
+#---- internal support functions
+
+def _format_linedata(linedata, indent, indent_width):
+    """Format specific linedata into a pleasant layout.
+    
+        "linedata" is a list of 2-tuples of the form:
+            (<item-display-string>, <item-docstring>)
+        "indent" is a string to use for one level of indentation
+        "indent_width" is a number of columns by which the
+            formatted data will be indented when printed.
+
+    The <item-display-string> column is held to 15 columns.
+    """
+    lines = []
+    WIDTH = 78 - indent_width
+    SPACING = 2
+    NAME_WIDTH_LOWER_BOUND = 13
+    NAME_WIDTH_UPPER_BOUND = 16
+    NAME_WIDTH = max([len(s) for s,d in linedata])
+    if NAME_WIDTH < NAME_WIDTH_LOWER_BOUND:
+        NAME_WIDTH = NAME_WIDTH_LOWER_BOUND
+    else:
+        NAME_WIDTH = NAME_WIDTH_UPPER_BOUND
+
+    DOC_WIDTH = WIDTH - NAME_WIDTH - SPACING
+    for namestr, doc in linedata:
+        line = indent + namestr
+        if len(namestr) <= NAME_WIDTH:
+            line += ' ' * (NAME_WIDTH + SPACING - len(namestr))
+        else:
+            lines.append(line)
+            line = indent + ' ' * (NAME_WIDTH + SPACING)
+        line += _summarize_doc(doc, DOC_WIDTH)
+        lines.append(line.rstrip())
+    return lines
+
+def _summarize_doc(doc, length=60):
+    r"""Parse out a short one line summary from the given doclines.
+    
+        "doc" is the doc string to summarize.
+        "length" is the max length for the summary
+
+    >>> _summarize_doc("this function does this")
+    'this function does this'
+    >>> _summarize_doc("this function does this", 10)
+    'this fu...'
+    >>> _summarize_doc("this function does this\nand that")
+    'this function does this and that'
+    >>> _summarize_doc("this function does this\n\nand that")
+    'this function does this'
+    """
+    import re
+    if doc is None:
+        return ""
+    assert length > 3, "length <= 3 is absurdly short for a doc summary"
+    doclines = doc.strip().splitlines(0)
+    if not doclines:
+        return ""
+
+    summlines = []
+    for i, line in enumerate(doclines):
+        stripped = line.strip()
+        if not stripped:
+            break
+        summlines.append(stripped)
+        if len(''.join(summlines)) >= length:
+            break
+
+    summary = ' '.join(summlines)
+    if len(summary) > length:
+        summary = summary[:length-3] + "..." 
+    return summary
+
+
+def line2argv(line):
+    r"""Parse the given line into an argument vector.
+    
+        "line" is the line of input to parse.
+
+    This may get niggly when dealing with quoting and escaping. The
+    current state of this parsing may not be completely thorough/correct
+    in this respect.
+    
+    >>> from cmdln import line2argv
+    >>> line2argv("foo")
+    ['foo']
+    >>> line2argv("foo bar")
+    ['foo', 'bar']
+    >>> line2argv("foo bar ")
+    ['foo', 'bar']
+    >>> line2argv(" foo bar")
+    ['foo', 'bar']
+
+    Quote handling:
+    
+    >>> line2argv("'foo bar'")
+    ['foo bar']
+    >>> line2argv('"foo bar"')
+    ['foo bar']
+    >>> line2argv(r'"foo\"bar"')
+    ['foo"bar']
+    >>> line2argv("'foo bar' spam")
+    ['foo bar', 'spam']
+    >>> line2argv("'foo 'bar spam")
+    ['foo bar', 'spam']
+    
+    >>> line2argv('some\tsimple\ttests')
+    ['some', 'simple', 'tests']
+    >>> line2argv('a "more complex" test')
+    ['a', 'more complex', 'test']
+    >>> line2argv('a more="complex test of " quotes')
+    ['a', 'more=complex test of ', 'quotes']
+    >>> line2argv('a more" complex test of " quotes')
+    ['a', 'more complex test of ', 'quotes']
+    >>> line2argv('an "embedded \\"quote\\""')
+    ['an', 'embedded "quote"']
+
+    # Komodo bug 48027
+    >>> line2argv('foo bar C:\\')
+    ['foo', 'bar', 'C:\\']
+
+    # Komodo change 127581
+    >>> line2argv(r'"\test\slash" "foo bar" "foo\"bar"')
+    ['\\test\\slash', 'foo bar', 'foo"bar']
+
+    # Komodo change 127629
+    >>> if sys.platform == "win32":
+    ...     line2argv(r'\foo\bar') == ['\\foo\\bar']
+    ...     line2argv(r'\\foo\\bar') == ['\\\\foo\\\\bar']
+    ...     line2argv('"foo') == ['foo']
+    ... else:
+    ...     line2argv(r'\foo\bar') == ['foobar']
+    ...     line2argv(r'\\foo\\bar') == ['\\foo\\bar']
+    ...     try:
+    ...         line2argv('"foo')
+    ...     except ValueError, ex:
+    ...         "not terminated" in str(ex)
+    True
+    True
+    True
+    """
+    import string
+    line = line.strip()
+    argv = []
+    state = "default"
+    arg = None  # the current argument being parsed
+    i = -1
+    while 1:
+        i += 1
+        if i >= len(line): break
+        ch = line[i]
+
+        if ch == "\\" and i+1 < len(line):
+            # escaped char always added to arg, regardless of state
+            if arg is None: arg = ""
+            if (sys.platform == "win32"
+                or state in ("double-quoted", "single-quoted")
+               ) and line[i+1] not in tuple('"\''):
+                arg += ch
+            i += 1
+            arg += line[i]
+            continue
+
+        if state == "single-quoted":
+            if ch == "'":
+                state = "default"
+            else:
+                arg += ch
+        elif state == "double-quoted":
+            if ch == '"':
+                state = "default"
+            else:
+                arg += ch
+        elif state == "default":
+            if ch == '"':
+                if arg is None: arg = ""
+                state = "double-quoted"
+            elif ch == "'":
+                if arg is None: arg = ""
+                state = "single-quoted"
+            elif ch in string.whitespace:
+                if arg is not None:
+                    argv.append(arg)
+                arg = None
+            else:
+                if arg is None: arg = ""
+                arg += ch
+    if arg is not None:
+        argv.append(arg)
+    if not sys.platform == "win32" and state != "default":
+        raise ValueError("command line is not terminated: unfinished %s "
+                         "segment" % state)
+    return argv
+
+
+def argv2line(argv):
+    r"""Put together the given argument vector into a command line.
+    
+        "argv" is the argument vector to process.
+    
+    >>> from cmdln import argv2line
+    >>> argv2line(['foo'])
+    'foo'
+    >>> argv2line(['foo', 'bar'])
+    'foo bar'
+    >>> argv2line(['foo', 'bar baz'])
+    'foo "bar baz"'
+    >>> argv2line(['foo"bar'])
+    'foo"bar'
+    >>> print argv2line(['foo" bar'])
+    'foo" bar'
+    >>> print argv2line(["foo' bar"])
+    "foo' bar"
+    >>> argv2line(["foo'bar"])
+    "foo'bar"
+    """
+    escapedArgs = []
+    for arg in argv:
+        if ' ' in arg and '"' not in arg:
+            arg = '"'+arg+'"'
+        elif ' ' in arg and "'" not in arg:
+            arg = "'"+arg+"'"
+        elif ' ' in arg:
+            arg = arg.replace('"', r'\"')
+            arg = '"'+arg+'"'
+        escapedArgs.append(arg)
+    return ' '.join(escapedArgs)
+
+
+# Recipe: dedent (0.1) in /Users/trentm/tm/recipes/cookbook
+def _dedentlines(lines, tabsize=8, skip_first_line=False):
+    """_dedentlines(lines, tabsize=8, skip_first_line=False) -> dedented lines
+    
+        "lines" is a list of lines to dedent.
+        "tabsize" is the tab width to use for indent width calculations.
+        "skip_first_line" is a boolean indicating if the first line should
+            be skipped for calculating the indent width and for dedenting.
+            This is sometimes useful for docstrings and similar.
+    
+    Same as dedent() except operates on a sequence of lines. Note: the
+    lines list is modified **in-place**.
+    """
+    DEBUG = False
+    if DEBUG: 
+        print "dedent: dedent(..., tabsize=%d, skip_first_line=%r)"\
+              % (tabsize, skip_first_line)
+    indents = []
+    margin = None
+    for i, line in enumerate(lines):
+        if i == 0 and skip_first_line: continue
+        indent = 0
+        for ch in line:
+            if ch == ' ':
+                indent += 1
+            elif ch == '\t':
+                indent += tabsize - (indent % tabsize)
+            elif ch in '\r\n':
+                continue # skip all-whitespace lines
+            else:
+                break
+        else:
+            continue # skip all-whitespace lines
+        if DEBUG: print "dedent: indent=%d: %r" % (indent, line)
+        if margin is None:
+            margin = indent
+        else:
+            margin = min(margin, indent)
+    if DEBUG: print "dedent: margin=%r" % margin
+
+    if margin is not None and margin > 0:
+        for i, line in enumerate(lines):
+            if i == 0 and skip_first_line: continue
+            removed = 0
+            for j, ch in enumerate(line):
+                if ch == ' ':
+                    removed += 1
+                elif ch == '\t':
+                    removed += tabsize - (removed % tabsize)
+                elif ch in '\r\n':
+                    if DEBUG: print "dedent: %r: EOL -> strip up to EOL" % line
+                    lines[i] = lines[i][j:]
+                    break
+                else:
+                    raise ValueError("unexpected non-whitespace char %r in "
+                                     "line %r while removing %d-space margin"
+                                     % (ch, line, margin))
+                if DEBUG:
+                    print "dedent: %r: %r -> removed %d/%d"\
+                          % (line, ch, removed, margin)
+                if removed == margin:
+                    lines[i] = lines[i][j+1:]
+                    break
+                elif removed > margin:
+                    lines[i] = ' '*(removed-margin) + lines[i][j+1:]
+                    break
+    return lines
+
+def _dedent(text, tabsize=8, skip_first_line=False):
+    """_dedent(text, tabsize=8, skip_first_line=False) -> dedented text
+
+        "text" is the text to dedent.
+        "tabsize" is the tab width to use for indent width calculations.
+        "skip_first_line" is a boolean indicating if the first line should
+            be skipped for calculating the indent width and for dedenting.
+            This is sometimes useful for docstrings and similar.
+    
+    textwrap.dedent(s), but don't expand tabs to spaces
+    """
+    lines = text.splitlines(1)
+    _dedentlines(lines, tabsize=tabsize, skip_first_line=skip_first_line)
+    return ''.join(lines)
+
+
+def _get_indent(marker, s, tab_width=8):
+    """_get_indent(marker, s, tab_width=8) ->
+        (<indentation-of-'marker'>, <indentation-width>)"""
+    # Figure out how much the marker is indented.
+    INDENT_CHARS = tuple(' \t')
+    start = s.index(marker)
+    i = start
+    while i > 0:
+        if s[i-1] not in INDENT_CHARS:
+            break
+        i -= 1
+    indent = s[i:start]
+    indent_width = 0
+    for ch in indent:
+        if ch == ' ':
+            indent_width += 1
+        elif ch == '\t':
+            indent_width += tab_width - (indent_width % tab_width)
+    return indent, indent_width
+
+def _get_trailing_whitespace(marker, s):
+    """Return the whitespace content trailing the given 'marker' in string 's',
+    up to and including a newline.
+    """
+    suffix = ''
+    start = s.index(marker) + len(marker)
+    i = start
+    while i < len(s):
+        if s[i] in ' \t':
+            suffix += s[i]
+        elif s[i] in '\r\n':
+            suffix += s[i]
+            if s[i] == '\r' and i+1 < len(s) and s[i+1] == '\n':
+                suffix += s[i+1]
+            break
+        else:
+            break
+        i += 1
+    return suffix
+
+
+
+#---- bash completion support
+# Note: This is still experimental. I expect to change this
+# significantly.
+#
+# To get Bash completion for a cmdln.Cmdln class, run the following
+# bash command:
+#   $ complete -C 'python -m cmdln /path/to/script.py CmdlnClass' cmdname
+# For example:
+#   $ complete -C 'python -m cmdln ~/bin/svn.py SVN' svn
+#
+#TODO: Simplify the above so don't have to given path to script (try to
+#      find it on PATH, if possible). Could also make class name
+#      optional if there is only one in the module (common case).
+
+if __name__ == "__main__" and len(sys.argv) == 6:
+    def _log(s):
+        return # no-op, comment out for debugging
+        from os.path import expanduser
+        fout = open(expanduser("~/tmp/bashcpln.log"), 'a')
+        fout.write(str(s) + '\n')
+        fout.close()
+
+    # Recipe: module_from_path (1.0.1+)
+    def _module_from_path(path):
+        import imp, os, sys
+        path = os.path.expanduser(path)
+        dir = os.path.dirname(path) or os.curdir
+        name = os.path.splitext(os.path.basename(path))[0]
+        sys.path.insert(0, dir)
+        try:
+            iinfo = imp.find_module(name, [dir])
+            return imp.load_module(name, *iinfo)
+        finally:
+            sys.path.remove(dir)
+
+    def _get_bash_cplns(script_path, class_name, cmd_name,
+                        token, preceding_token):
+        _log('--')
+        _log('get_cplns(%r, %r, %r, %r, %r)'
+             % (script_path, class_name, cmd_name, token, preceding_token))
+        comp_line = os.environ["COMP_LINE"]
+        comp_point = int(os.environ["COMP_POINT"])
+        _log("COMP_LINE: %r" % comp_line)
+        _log("COMP_POINT: %r" % comp_point)
+
+        try:
+            script = _module_from_path(script_path)
+        except ImportError, ex:
+            _log("error importing `%s': %s" % (script_path, ex))
+            return []
+        shell = getattr(script, class_name)()
+        cmd_map = shell._get_canonical_map()
+        del cmd_map["EOF"]
+
+        # Determine if completing the sub-command name.
+        parts = comp_line[:comp_point].split(None, 1)
+        _log(parts)
+        if len(parts) == 1 or not (' ' in parts[1] or '\t' in parts[1]):
+            #TODO: if parts[1].startswith('-'): handle top-level opts
+            _log("complete sub-command names")
+            matches = {}
+            for name, canon_name in cmd_map.items():
+                if name.startswith(token):
+                    matches[name] = canon_name
+            if not matches:
+                return []
+            elif len(matches) == 1:
+                return matches.keys()
+            elif len(set(matches.values())) == 1:
+                return [matches.values()[0]]
+            else:
+                return matches.keys()
+
+        # Otherwise, complete options for the given sub-command.
+        #TODO: refine this so it does the right thing with option args
+        if token.startswith('-'):
+            cmd_name = comp_line.split(None, 2)[1]
+            try:
+                cmd_canon_name = cmd_map[cmd_name]
+            except KeyError:
+                return []
+            handler = shell._get_cmd_handler(cmd_canon_name)
+            optparser = getattr(handler, "optparser", None)
+            if optparser is None:
+                optparser = SubCmdOptionParser()
+            opt_strs = []
+            for option in optparser.option_list:
+                for opt_str in option._short_opts + option._long_opts:
+                    if opt_str.startswith(token):
+                        opt_strs.append(opt_str)
+            return opt_strs
+
+        return []
+
+    for cpln in _get_bash_cplns(*sys.argv[1:]):
+        print cpln
+