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#!/usr/bin/env python
#
# test_multibytecodec_support.py
#   Common Unittest Routines for CJK codecs
#

import sys, codecs
import unittest, re
from test import support
from io import BytesIO

class TestBase:
    encoding        = ''   # codec name
    codec           = None # codec tuple (with 4 elements)
    tstring         = None # must set. 2 strings to test StreamReader

    codectests      = None # must set. codec test tuple
    roundtriptest   = 1    # set if roundtrip is possible with unicode
    has_iso10646    = 0    # set if this encoding contains whole iso10646 map
    xmlcharnametest = None # string to test xmlcharrefreplace
    unmappedunicode = '\udeee' # a unicode codepoint that is not mapped.

    def setUp(self):
        if self.codec is None:
            self.codec = codecs.lookup(self.encoding)
        self.encode = self.codec.encode
        self.decode = self.codec.decode
        self.reader = self.codec.streamreader
        self.writer = self.codec.streamwriter
        self.incrementalencoder = self.codec.incrementalencoder
        self.incrementaldecoder = self.codec.incrementaldecoder

    def test_chunkcoding(self):
        tstring_lines = []
        for b in self.tstring:
            lines = b.split(b"\n")
            last = lines.pop()
            assert last == b""
            lines = [line + b"\n" for line in lines]
            tstring_lines.append(lines)
        for native, utf8 in zip(*tstring_lines):
            u = self.decode(native)[0]
            self.assertEqual(u, utf8.decode('utf-8'))
            if self.roundtriptest:
                self.assertEqual(native, self.encode(u)[0])

    def test_errorhandle(self):
        for source, scheme, expected in self.codectests:
            if isinstance(source, bytes):
                func = self.decode
            else:
                func = self.encode
            if expected:
                result = func(source, scheme)[0]
                if func is self.decode:
                    self.assert_(type(result) is str, type(result))
                else:
                    self.assert_(type(result) is bytes, type(result))
                self.assertEqual(result, expected)
            else:
                self.assertRaises(UnicodeError, func, source, scheme)

    def test_xmlcharrefreplace(self):
        if self.has_iso10646:
            return

        s = "\u0b13\u0b23\u0b60 nd eggs"
        self.assertEqual(
            self.encode(s, "xmlcharrefreplace")[0],
            b"ଓଣୠ nd eggs"
        )

    def test_customreplace_encode(self):
        if self.has_iso10646:
            return

        from html.entities import codepoint2name

        def xmlcharnamereplace(exc):
            if not isinstance(exc, UnicodeEncodeError):
                raise TypeError("don't know how to handle %r" % exc)
            l = []
            for c in exc.object[exc.start:exc.end]:
                if ord(c) in codepoint2name:
                    l.append("&%s;" % codepoint2name[ord(c)])
                else:
                    l.append("&#%d;" % ord(c))
            return ("".join(l), exc.end)

        codecs.register_error("test.xmlcharnamereplace", xmlcharnamereplace)

        if self.xmlcharnametest:
            sin, sout = self.xmlcharnametest
        else:
            sin = "\xab\u211c\xbb = \u2329\u1234\u232a"
            sout = b"«ℜ» = ⟨ሴ⟩"
        self.assertEqual(self.encode(sin,
                                    "test.xmlcharnamereplace")[0], sout)

    def test_callback_wrong_objects(self):
        def myreplace(exc):
            return (ret, exc.end)
        codecs.register_error("test.cjktest", myreplace)

        for ret in ([1, 2, 3], [], None, object(), b'string', b''):
            self.assertRaises(TypeError, self.encode, self.unmappedunicode,
                              'test.cjktest')

    def test_callback_long_index(self):
        def myreplace(exc):
            return ('x', int(exc.end))
        codecs.register_error("test.cjktest", myreplace)
        self.assertEqual(self.encode('abcd' + self.unmappedunicode + 'efgh',
                                     'test.cjktest'), (b'abcdxefgh', 9))

        def myreplace(exc):
            return ('x', sys.maxsize + 1)
        codecs.register_error("test.cjktest", myreplace)
        self.assertRaises(IndexError, self.encode, self.unmappedunicode,
                          'test.cjktest')

    def test_callback_None_index(self):
        def myreplace(exc):
            return ('x', None)
        codecs.register_error("test.cjktest", myreplace)
        self.assertRaises(TypeError, self.encode, self.unmappedunicode,
                          'test.cjktest')

    def test_callback_backward_index(self):
        def myreplace(exc):
            if myreplace.limit > 0:
                myreplace.limit -= 1
                return ('REPLACED', 0)
            else:
                return ('TERMINAL', exc.end)
        myreplace.limit = 3
        codecs.register_error("test.cjktest", myreplace)
        self.assertEqual(self.encode('abcd' + self.unmappedunicode + 'efgh',
                                     'test.cjktest'),
                (b'abcdREPLACEDabcdREPLACEDabcdREPLACEDabcdTERMINALefgh', 9))

    def test_callback_forward_index(self):
        def myreplace(exc):
            return ('REPLACED', exc.end + 2)
        codecs.register_error("test.cjktest", myreplace)
        self.assertEqual(self.encode('abcd' + self.unmappedunicode + 'efgh',
                                     'test.cjktest'), (b'abcdREPLACEDgh', 9))

    def test_callback_index_outofbound(self):
        def myreplace(exc):
            return ('TERM', 100)
        codecs.register_error("test.cjktest", myreplace)
        self.assertRaises(IndexError, self.encode, self.unmappedunicode,
                          'test.cjktest')

    def test_incrementalencoder(self):
        UTF8Reader = codecs.getreader('utf-8')
        for sizehint in [None] + list(range(1, 33)) + \
                        [64, 128, 256, 512, 1024]:
            istream = UTF8Reader(BytesIO(self.tstring[1]))
            ostream = BytesIO()
            encoder = self.incrementalencoder()
            while 1:
                if sizehint is not None:
                    data = istream.read(sizehint)
                else:
                    data = istream.read()

                if not data:
                    break
                e = encoder.encode(data)
                ostream.write(e)

            self.assertEqual(ostream.getvalue(), self.tstring[0])

    def test_incrementaldecoder(self):
        UTF8Writer = codecs.getwriter('utf-8')
        for sizehint in [None, -1] + list(range(1, 33)) + \
                        [64, 128, 256, 512, 1024]:
            istream = BytesIO(self.tstring[0])
            ostream = UTF8Writer(BytesIO())
            decoder = self.incrementaldecoder()
            while 1:
                data = istream.read(sizehint)
                if not data:
                    break
                else:
                    u = decoder.decode(data)
                    ostream.write(u)

            self.assertEqual(ostream.getvalue(), self.tstring[1])

    def test_incrementalencoder_error_callback(self):
        inv = self.unmappedunicode

        e = self.incrementalencoder()
        self.assertRaises(UnicodeEncodeError, e.encode, inv, True)

        e.errors = 'ignore'
        self.assertEqual(e.encode(inv, True), b'')

        e.reset()
        def tempreplace(exc):
            return ('called', exc.end)
        codecs.register_error('test.incremental_error_callback', tempreplace)
        e.errors = 'test.incremental_error_callback'
        self.assertEqual(e.encode(inv, True), b'called')

        # again
        e.errors = 'ignore'
        self.assertEqual(e.encode(inv, True), b'')

    def test_streamreader(self):
        UTF8Writer = codecs.getwriter('utf-8')
        for name in ["read", "readline", "readlines"]:
            for sizehint in [None, -1] + list(range(1, 33)) + \
                            [64, 128, 256, 512, 1024]:
                istream = self.reader(BytesIO(self.tstring[0]))
                ostream = UTF8Writer(BytesIO())
                func = getattr(istream, name)
                while 1:
                    data = func(sizehint)
                    if not data:
                        break
                    if name == "readlines":
                        ostream.writelines(data)
                    else:
                        ostream.write(data)

                self.assertEqual(ostream.getvalue(), self.tstring[1])

    def test_streamwriter(self):
        readfuncs = ('read', 'readline', 'readlines')
        UTF8Reader = codecs.getreader('utf-8')
        for name in readfuncs:
            for sizehint in [None] + list(range(1, 33)) + \
                            [64, 128, 256, 512, 1024]:
                istream = UTF8Reader(BytesIO(self.tstring[1]))
                ostream = self.writer(BytesIO())
                func = getattr(istream, name)
                while 1:
                    if sizehint is not None:
                        data = func(sizehint)
                    else:
                        data = func()

                    if not data:
                        break
                    if name == "readlines":
                        ostream.writelines(data)
                    else:
                        ostream.write(data)

                self.assertEqual(ostream.getvalue(), self.tstring[0])

if len('\U00012345') == 2: # ucs2 build
    _unichr = chr
    def chr(v):
        if v >= 0x10000:
            return _unichr(0xd800 + ((v - 0x10000) >> 10)) + \
                   _unichr(0xdc00 + ((v - 0x10000) & 0x3ff))
        else:
            return _unichr(v)
    _ord = ord
    def ord(c):
        if len(c) == 2:
            return 0x10000 + ((_ord(c[0]) - 0xd800) << 10) + \
                          (ord(c[1]) - 0xdc00)
        else:
            return _ord(c)

class TestBase_Mapping(unittest.TestCase):
    pass_enctest = []
    pass_dectest = []
    supmaps = []

    def __init__(self, *args, **kw):
        unittest.TestCase.__init__(self, *args, **kw)
        try:
            self.open_mapping_file() # test it to report the error early
        except IOError:
            raise support.TestSkipped("Could not retrieve "+self.mapfileurl)

    def open_mapping_file(self):
        return support.open_urlresource(self.mapfileurl)

    def test_mapping_file(self):
        if self.mapfileurl.endswith('.xml'):
            self._test_mapping_file_ucm()
        else:
            self._test_mapping_file_plain()

    def _test_mapping_file_plain(self):
        unichrs = lambda s: ''.join(map(chr, map(eval, s.split('+'))))
        urt_wa = {}

        for line in self.open_mapping_file():
            if not line:
                break
            data = line.split('#')[0].strip().split()
            if len(data) != 2:
                continue

            csetval = eval(data[0])
            if csetval <= 0x7F:
                csetch = bytes([csetval & 0xff])
            elif csetval >= 0x1000000:
                csetch = bytes([(csetval >> 24), ((csetval >> 16) & 0xff),
                                ((csetval >> 8) & 0xff), (csetval & 0xff)])
            elif csetval >= 0x10000:
                csetch = bytes([(csetval >> 16), ((csetval >> 8) & 0xff),
                                (csetval & 0xff)])
            elif csetval >= 0x100:
                csetch = bytes([(csetval >> 8), (csetval & 0xff)])
            else:
                continue

            unich = unichrs(data[1])
            if ord(unich) == 0xfffd or unich in urt_wa:
                continue
            urt_wa[unich] = csetch

            self._testpoint(csetch, unich)

    def _test_mapping_file_ucm(self):
        ucmdata = self.open_mapping_file().read()
        uc = re.findall('<a u="([A-F0-9]{4})" b="([0-9A-F ]+)"/>', ucmdata)
        for uni, coded in uc:
            unich = chr(int(uni, 16))
            codech = bytes(int(c, 16) for c in coded.split())
            self._testpoint(codech, unich)

    def test_mapping_supplemental(self):
        for mapping in self.supmaps:
            self._testpoint(*mapping)

    def _testpoint(self, csetch, unich):
        if (csetch, unich) not in self.pass_enctest:
            self.assertEqual(unich.encode(self.encoding), csetch)
        if (csetch, unich) not in self.pass_dectest:
            self.assertEqual(str(csetch, self.encoding), unich)

def load_teststring(encoding):
    from test import cjkencodings_test
    return cjkencodings_test.teststring[encoding]
n1899' href='#n1899'>1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327
# Author: Steven J. Bethard <steven.bethard@gmail.com>.

"""Command-line parsing library

This module is an optparse-inspired command-line parsing library that:

    - handles both optional and positional arguments
    - produces highly informative usage messages
    - supports parsers that dispatch to sub-parsers

The following is a simple usage example that sums integers from the
command-line and writes the result to a file::

    parser = argparse.ArgumentParser(
        description='sum the integers at the command line')
    parser.add_argument(
        'integers', metavar='int', nargs='+', type=int,
        help='an integer to be summed')
    parser.add_argument(
        '--log', default=sys.stdout, type=argparse.FileType('w'),
        help='the file where the sum should be written')
    args = parser.parse_args()
    args.log.write('%s' % sum(args.integers))
    args.log.close()

The module contains the following public classes:

    - ArgumentParser -- The main entry point for command-line parsing. As the
        example above shows, the add_argument() method is used to populate
        the parser with actions for optional and positional arguments. Then
        the parse_args() method is invoked to convert the args at the
        command-line into an object with attributes.

    - ArgumentError -- The exception raised by ArgumentParser objects when
        there are errors with the parser's actions. Errors raised while
        parsing the command-line are caught by ArgumentParser and emitted
        as command-line messages.

    - FileType -- A factory for defining types of files to be created. As the
        example above shows, instances of FileType are typically passed as
        the type= argument of add_argument() calls.

    - Action -- The base class for parser actions. Typically actions are
        selected by passing strings like 'store_true' or 'append_const' to
        the action= argument of add_argument(). However, for greater
        customization of ArgumentParser actions, subclasses of Action may
        be defined and passed as the action= argument.

    - HelpFormatter, RawDescriptionHelpFormatter, RawTextHelpFormatter,
        ArgumentDefaultsHelpFormatter -- Formatter classes which
        may be passed as the formatter_class= argument to the
        ArgumentParser constructor. HelpFormatter is the default,
        RawDescriptionHelpFormatter and RawTextHelpFormatter tell the parser
        not to change the formatting for help text, and
        ArgumentDefaultsHelpFormatter adds information about argument defaults
        to the help.

All other classes in this module are considered implementation details.
(Also note that HelpFormatter and RawDescriptionHelpFormatter are only
considered public as object names -- the API of the formatter objects is
still considered an implementation detail.)
"""

__version__ = '1.1'
__all__ = [
    'ArgumentParser',
    'ArgumentError',
    'ArgumentTypeError',
    'FileType',
    'HelpFormatter',
    'ArgumentDefaultsHelpFormatter',
    'RawDescriptionHelpFormatter',
    'RawTextHelpFormatter',
    'Namespace',
    'Action',
    'ONE_OR_MORE',
    'OPTIONAL',
    'PARSER',
    'REMAINDER',
    'SUPPRESS',
    'ZERO_OR_MORE',
]


import copy as _copy
import os as _os
import re as _re
import sys as _sys
import textwrap as _textwrap

from gettext import gettext as _


def _callable(obj):
    return hasattr(obj, '__call__') or hasattr(obj, '__bases__')


SUPPRESS = '==SUPPRESS=='

OPTIONAL = '?'
ZERO_OR_MORE = '*'
ONE_OR_MORE = '+'
PARSER = 'A...'
REMAINDER = '...'

# =============================
# Utility functions and classes
# =============================

class _AttributeHolder(object):
    """Abstract base class that provides __repr__.

    The __repr__ method returns a string in the format::
        ClassName(attr=name, attr=name, ...)
    The attributes are determined either by a class-level attribute,
    '_kwarg_names', or by inspecting the instance __dict__.
    """

    def __repr__(self):
        type_name = type(self).__name__
        arg_strings = []
        for arg in self._get_args():
            arg_strings.append(repr(arg))
        for name, value in self._get_kwargs():
            arg_strings.append('%s=%r' % (name, value))
        return '%s(%s)' % (type_name, ', '.join(arg_strings))

    def _get_kwargs(self):
        return sorted(self.__dict__.items())

    def _get_args(self):
        return []


def _ensure_value(namespace, name, value):
    if getattr(namespace, name, None) is None:
        setattr(namespace, name, value)
    return getattr(namespace, name)


# ===============
# Formatting Help
# ===============

class HelpFormatter(object):
    """Formatter for generating usage messages and argument help strings.

    Only the name of this class is considered a public API. All the methods
    provided by the class are considered an implementation detail.
    """

    def __init__(self,
                 prog,
                 indent_increment=2,
                 max_help_position=24,
                 width=None):

        # default setting for width
        if width is None:
            try:
                width = int(_os.environ['COLUMNS'])
            except (KeyError, ValueError):
                width = 80
            width -= 2

        self._prog = prog
        self._indent_increment = indent_increment
        self._max_help_position = max_help_position
        self._width = width

        self._current_indent = 0
        self._level = 0
        self._action_max_length = 0

        self._root_section = self._Section(self, None)
        self._current_section = self._root_section

        self._whitespace_matcher = _re.compile(r'\s+')
        self._long_break_matcher = _re.compile(r'\n\n\n+')

    # ===============================
    # Section and indentation methods
    # ===============================
    def _indent(self):
        self._current_indent += self._indent_increment
        self._level += 1

    def _dedent(self):
        self._current_indent -= self._indent_increment
        assert self._current_indent >= 0, 'Indent decreased below 0.'
        self._level -= 1

    class _Section(object):

        def __init__(self, formatter, parent, heading=None):
            self.formatter = formatter
            self.parent = parent
            self.heading = heading
            self.items = []

        def format_help(self):
            # format the indented section
            if self.parent is not None:
                self.formatter._indent()
            join = self.formatter._join_parts
            for func, args in self.items:
                func(*args)
            item_help = join([func(*args) for func, args in self.items])
            if self.parent is not None:
                self.formatter._dedent()

            # return nothing if the section was empty
            if not item_help:
                return ''

            # add the heading if the section was non-empty
            if self.heading is not SUPPRESS and self.heading is not None:
                current_indent = self.formatter._current_indent
                heading = '%*s%s:\n' % (current_indent, '', self.heading)
            else:
                heading = ''

            # join the section-initial newline, the heading and the help
            return join(['\n', heading, item_help, '\n'])

    def _add_item(self, func, args):
        self._current_section.items.append((func, args))

    # ========================
    # Message building methods
    # ========================
    def start_section(self, heading):
        self._indent()
        section = self._Section(self, self._current_section, heading)
        self._add_item(section.format_help, [])
        self._current_section = section

    def end_section(self):
        self._current_section = self._current_section.parent
        self._dedent()

    def add_text(self, text):
        if text is not SUPPRESS and text is not None:
            self._add_item(self._format_text, [text])

    def add_usage(self, usage, actions, groups, prefix=None):
        if usage is not SUPPRESS:
            args = usage, actions, groups, prefix
            self._add_item(self._format_usage, args)

    def add_argument(self, action):
        if action.help is not SUPPRESS:

            # find all invocations
            get_invocation = self._format_action_invocation
            invocations = [get_invocation(action)]
            for subaction in self._iter_indented_subactions(action):
                invocations.append(get_invocation(subaction))

            # update the maximum item length
            invocation_length = max([len(s) for s in invocations])
            action_length = invocation_length + self._current_indent
            self._action_max_length = max(self._action_max_length,
                                          action_length)

            # add the item to the list
            self._add_item(self._format_action, [action])

    def add_arguments(self, actions):
        for action in actions:
            self.add_argument(action)

    # =======================
    # Help-formatting methods
    # =======================
    def format_help(self):
        help = self._root_section.format_help()
        if help:
            help = self._long_break_matcher.sub('\n\n', help)
            help = help.strip('\n') + '\n'
        return help

    def _join_parts(self, part_strings):
        return ''.join([part
                        for part in part_strings
                        if part and part is not SUPPRESS])

    def _format_usage(self, usage, actions, groups, prefix):
        if prefix is None:
            prefix = _('usage: ')

        # if usage is specified, use that
        if usage is not None:
            usage = usage % dict(prog=self._prog)

        # if no optionals or positionals are available, usage is just prog
        elif usage is None and not actions:
            usage = '%(prog)s' % dict(prog=self._prog)

        # if optionals and positionals are available, calculate usage
        elif usage is None:
            prog = '%(prog)s' % dict(prog=self._prog)

            # split optionals from positionals
            optionals = []
            positionals = []
            for action in actions:
                if action.option_strings:
                    optionals.append(action)
                else:
                    positionals.append(action)

            # build full usage string
            format = self._format_actions_usage
            action_usage = format(optionals + positionals, groups)
            usage = ' '.join([s for s in [prog, action_usage] if s])

            # wrap the usage parts if it's too long
            text_width = self._width - self._current_indent
            if len(prefix) + len(usage) > text_width:

                # break usage into wrappable parts
                part_regexp = r'\(.*?\)+|\[.*?\]+|\S+'
                opt_usage = format(optionals, groups)
                pos_usage = format(positionals, groups)
                opt_parts = _re.findall(part_regexp, opt_usage)
                pos_parts = _re.findall(part_regexp, pos_usage)
                assert ' '.join(opt_parts) == opt_usage
                assert ' '.join(pos_parts) == pos_usage

                # helper for wrapping lines
                def get_lines(parts, indent, prefix=None):
                    lines = []
                    line = []
                    if prefix is not None:
                        line_len = len(prefix) - 1
                    else:
                        line_len = len(indent) - 1
                    for part in parts:
                        if line_len + 1 + len(part) > text_width:
                            lines.append(indent + ' '.join(line))
                            line = []
                            line_len = len(indent) - 1
                        line.append(part)
                        line_len += len(part) + 1
                    if line:
                        lines.append(indent + ' '.join(line))
                    if prefix is not None:
                        lines[0] = lines[0][len(indent):]
                    return lines

                # if prog is short, follow it with optionals or positionals
                if len(prefix) + len(prog) <= 0.75 * text_width:
                    indent = ' ' * (len(prefix) + len(prog) + 1)
                    if opt_parts:
                        lines = get_lines([prog] + opt_parts, indent, prefix)
                        lines.extend(get_lines(pos_parts, indent))
                    elif pos_parts:
                        lines = get_lines([prog] + pos_parts, indent, prefix)
                    else:
                        lines = [prog]

                # if prog is long, put it on its own line
                else:
                    indent = ' ' * len(prefix)
                    parts = opt_parts + pos_parts
                    lines = get_lines(parts, indent)
                    if len(lines) > 1:
                        lines = []
                        lines.extend(get_lines(opt_parts, indent))
                        lines.extend(get_lines(pos_parts, indent))
                    lines = [prog] + lines

                # join lines into usage
                usage = '\n'.join(lines)

        # prefix with 'usage:'
        return '%s%s\n\n' % (prefix, usage)

    def _format_actions_usage(self, actions, groups):
        # find group indices and identify actions in groups
        group_actions = set()
        inserts = {}
        for group in groups:
            try:
                start = actions.index(group._group_actions[0])
            except ValueError:
                continue
            else:
                end = start + len(group._group_actions)
                if actions[start:end] == group._group_actions:
                    for action in group._group_actions:
                        group_actions.add(action)
                    if not group.required:
                        if start in inserts:
                            inserts[start] += ' ['
                        else:
                            inserts[start] = '['
                        inserts[end] = ']'
                    else:
                        if start in inserts:
                            inserts[start] += ' ('
                        else:
                            inserts[start] = '('
                        inserts[end] = ')'
                    for i in range(start + 1, end):
                        inserts[i] = '|'

        # collect all actions format strings
        parts = []
        for i, action in enumerate(actions):

            # suppressed arguments are marked with None
            # remove | separators for suppressed arguments
            if action.help is SUPPRESS:
                parts.append(None)
                if inserts.get(i) == '|':
                    inserts.pop(i)
                elif inserts.get(i + 1) == '|':
                    inserts.pop(i + 1)

            # produce all arg strings
            elif not action.option_strings:
                part = self._format_args(action, action.dest)

                # if it's in a group, strip the outer []
                if action in group_actions:
                    if part[0] == '[' and part[-1] == ']':
                        part = part[1:-1]

                # add the action string to the list
                parts.append(part)

            # produce the first way to invoke the option in brackets
            else:
                option_string = action.option_strings[0]

                # if the Optional doesn't take a value, format is:
                #    -s or --long
                if action.nargs == 0:
                    part = '%s' % option_string

                # if the Optional takes a value, format is:
                #    -s ARGS or --long ARGS
                else:
                    default = action.dest.upper()
                    args_string = self._format_args(action, default)
                    part = '%s %s' % (option_string, args_string)

                # make it look optional if it's not required or in a group
                if not action.required and action not in group_actions:
                    part = '[%s]' % part

                # add the action string to the list
                parts.append(part)

        # insert things at the necessary indices
        for i in sorted(inserts, reverse=True):
            parts[i:i] = [inserts[i]]

        # join all the action items with spaces
        text = ' '.join([item for item in parts if item is not None])

        # clean up separators for mutually exclusive groups
        open = r'[\[(]'
        close = r'[\])]'
        text = _re.sub(r'(%s) ' % open, r'\1', text)
        text = _re.sub(r' (%s)' % close, r'\1', text)
        text = _re.sub(r'%s *%s' % (open, close), r'', text)
        text = _re.sub(r'\(([^|]*)\)', r'\1', text)
        text = text.strip()

        # return the text
        return text

    def _format_text(self, text):
        if '%(prog)' in text:
            text = text % dict(prog=self._prog)
        text_width = self._width - self._current_indent
        indent = ' ' * self._current_indent
        return self._fill_text(text, text_width, indent) + '\n\n'

    def _format_action(self, action):
        # determine the required width and the entry label
        help_position = min(self._action_max_length + 2,
                            self._max_help_position)
        help_width = self._width - help_position
        action_width = help_position - self._current_indent - 2
        action_header = self._format_action_invocation(action)

        # ho nelp; start on same line and add a final newline
        if not action.help:
            tup = self._current_indent, '', action_header
            action_header = '%*s%s\n' % tup

        # short action name; start on the same line and pad two spaces
        elif len(action_header) <= action_width:
            tup = self._current_indent, '', action_width, action_header
            action_header = '%*s%-*s  ' % tup
            indent_first = 0

        # long action name; start on the next line
        else:
            tup = self._current_indent, '', action_header
            action_header = '%*s%s\n' % tup
            indent_first = help_position

        # collect the pieces of the action help
        parts = [action_header]

        # if there was help for the action, add lines of help text
        if action.help:
            help_text = self._expand_help(action)
            help_lines = self._split_lines(help_text, help_width)
            parts.append('%*s%s\n' % (indent_first, '', help_lines[0]))
            for line in help_lines[1:]:
                parts.append('%*s%s\n' % (help_position, '', line))

        # or add a newline if the description doesn't end with one
        elif not action_header.endswith('\n'):
            parts.append('\n')

        # if there are any sub-actions, add their help as well
        for subaction in self._iter_indented_subactions(action):
            parts.append(self._format_action(subaction))

        # return a single string
        return self._join_parts(parts)

    def _format_action_invocation(self, action):
        if not action.option_strings:
            metavar, = self._metavar_formatter(action, action.dest)(1)
            return metavar

        else:
            parts = []

            # if the Optional doesn't take a value, format is:
            #    -s, --long
            if action.nargs == 0:
                parts.extend(action.option_strings)

            # if the Optional takes a value, format is:
            #    -s ARGS, --long ARGS
            else:
                default = action.dest.upper()
                args_string = self._format_args(action, default)
                for option_string in action.option_strings:
                    parts.append('%s %s' % (option_string, args_string))

            return ', '.join(parts)

    def _metavar_formatter(self, action, default_metavar):
        if action.metavar is not None:
            result = action.metavar
        elif action.choices is not None: