"""
Argparse was written by Steven Bethard <steven.bethard@gmail.com>.
Copyright (c) 2006 Steven J. Bethard. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
* Neither the name of the author nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
"""
import os as _os
import re as _re
import sys as _sys
import textwrap as _textwrap
from gettext import gettext
SUPPRESS = '==SUPPRESS=='
OPTIONAL = '?'
ZERO_OR_MORE = '*'
ONE_OR_MORE = '+'
PARSER = '==PARSER=='
# =============================
# 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):
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, optionals, positionals, prefix=None):
if usage is not SUPPRESS:
args = usage, optionals, positionals, prefix
self._add_item(self._format_usage, args)
def add_argument(self, action):
if action.help is not SUPPRESS:
# update the maximum item length
invocation = self._format_action_invocation(action)
action_length = len(invocation) + 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() % dict(prog=self._prog)
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, optionals, positionals, prefix):
if prefix is None:
prefix = _('usage: ')
# if no optionals or positionals are available, usage is just prog
if usage is None and not optionals and not positionals:
usage = '%(prog)s'
# if optionals and positionals are available, calculate usage
elif usage is None:
usage = '%(prog)s' % dict(prog=self._prog)
# determine width of "usage: PROG" and width of text
prefix_width = len(prefix) + len(usage) + 1
prefix_indent = self._current_indent + prefix_width
text_width = self._width - self._current_indent
# put them on one line if they're short enough
format = self._format_actions_usage
action_usage = format(optionals + positionals)
if prefix_width + len(action_usage) + 1 < text_width:
usage = '%s %s' % (usage, action_usage)
# if they're long, wrap optionals and positionals individually
else:
optional_usage = format(optionals)
positional_usage = format(positionals)
indent = ' ' * prefix_indent
# usage is made of PROG, optionals and positionals
parts = [usage, ' ']
# options always get added right after PROG
if optional_usage:
parts.append(_textwrap.fill(
optional_usage, text_width,
initial_indent=indent,
subsequent_indent=indent).lstrip())
# if there were options, put arguments on the next line
# otherwise, start them right after PROG
if positional_usage:
part = _textwrap.fill(
positional_usage, text_width,
initial_indent=indent,
subsequent_indent=indent).lstrip()
if optional_usage:
part = '\n' + indent + part
parts.append(part)
usage = ''.join(parts)
# prefix with 'usage:'
return '%s%s\n\n' % (prefix, usage)
def _format_actions_usage(self, actions):
parts = []
for action in actions:
if action.help is SUPPRESS:
continue
# produce all arg strings
if not action.option_strings:
parts.append(self._format_args(action, action.dest))
# 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:
parts.append('[%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)
parts.append('[%s %s]' % (option_string, args_string))
return ' '.join(parts)
def _format_text(self, text):
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')
# return a single string
return self._join_parts(parts)
def _format_action_invocation(self, action):
if not action.option_strings:
return self._format_metavar(action, action.dest)
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 _format_metavar(self, action, default_metavar):
if action.metavar is not None:
name = action.metavar
elif action.choices is not None:
choice_strs = (str(choice) for choice in action.choices)
name = '{%s}' % ','.join(choice_strs)
else:
name = default_metavar
return name
def _format_args(self, action, default_metavar):
name = self._format_metavar(action, default_metavar)
if action.nargs is None:
result = name
elif action.nargs == OPTIONAL:
result = '[%s]' % name
elif action.nargs == ZERO_OR_MORE:
result = '[%s [%s ...]]' % (name, name)
elif action.nargs == ONE_OR_MORE:
result = '%s [%s ...]' % (name, name)
elif action.nargs is PARSER:
result = '%s ...' % name
else:
result = ' '.join([name] * action.nargs)
return result
def _expand_help(self, action):
params = dict(vars(action), prog=self._prog)
for name, value in params.items():
if value is SUPPRESS:
del params[name]
if params.get('choices') is not None:
choices_str = ', '.join(str(c) for c in params['choices'])
params['choices'] = choices_str
return action.help % params
def _split_lines(self, text, width):
text = self._whitespace_matcher.sub(' ', text).strip()
return _textwrap.wrap(text, width)
def _fill_text(self, text, width, indent):
text = self._whitespace_matcher.sub(' ', text).strip()
return _textwrap.fill(text, width, initial_indent=indent,
subsequent_indent=indent)
class RawDescriptionHelpFormatter(HelpFormatter):
def _fill_text(self, text, width, indent):
return ''.join(indent + line for line in text.splitlines(True))
class RawTextHelpFormatter(RawDescriptionHelpFormatter):
def _split_lines(self, text, width):
return text.splitlines()
# =====================
# Options and Arguments
# =====================
class ArgumentError(Exception):
"""ArgumentError(message, argument)
Raised whenever there was an error creating or using an argument
(optional or positional).
The string value of this exception is the message, augmented with
information about the argument that caused it.
"""
def __init__(self, argument, message):
if argument.option_strings:
self.argument_name = '/'.join(argument.option_strings)
elif argument.metavar not in (None, SUPPRESS):
self.argument_name = argument.metavar
elif argument.dest not in (None, SUPPRESS):
self.argument_name = argument.dest
else:
self.argument_name = None
self.message = message
def __str__(self):
if self.argument_name is None:
format = '%(message)s'
else:
format = 'argument %(argument_name)s: %(message)s'
return format % dict(message=self.message,
argument_name=self.argument_name)
# ==============
# Action classes
# ==============
class Action(_AttributeHolder):
"""Action(*strings, **options)
Action objects hold the information necessary to convert a
set of command-line arguments (possibly including an initial option
string) into the desired Python object(s).
Keyword Arguments:
option_strings -- A list of command-line option strings which
should be associated with this action.
dest -- The name of the attribute to hold the created object(s)
nargs -- The number of command-line arguments that should be consumed.
By default, one argument will be consumed and a single value will
be produced. Other values include:
* N (an integer) consumes N arguments (and produces a list)
* '?' consumes zero or one arguments
* '*' consumes zero or more arguments (and produces a list)
* '+' consumes one or more arguments (and produces a list)
Note that the difference between the default and nargs=1 is that
with the default, a single value will be produced, while with
nargs=1, a list containing a single value will be produced.
const -- The value to be produced if the option is specified and the
option uses an action that takes no values.
default -- The value to be produced if the option is not specified.
type -- The type which the command-line arguments should be converted
to, should be one of 'string', 'int', 'float', 'complex' or a
callable object that accepts a single string argument. If None,
'string' is assumed.
choices -- A container of values that should be allowed. If not None,
after a command-line argument has been converted to the appropriate
type, an exception will be raised if it is not a member of this
collection.
required -- True if the action must always be specified at the command
line. This is only meaningful for optional command-line arguments.
help -- The help string describing the argument.
metavar -- The name to be used for the option's argument with the help
string. If None, the 'dest' value will be used as the name.
"""
def __init__(self,
option_strings,
dest,
nargs=None,
const=None,
default=None,
type=None,
choices=None,
required=False,
help=None,
metavar=None):
self.option_strings = option_strings
self.dest = dest
self.nargs = nargs
self.const = const
self.default = default
self.type = type
self.choices = choices
self.required = required
self.help = help
self.metavar = metavar
def _get_kwargs(self):
names = [
'option_strings',
'dest',
'nargs',
'const',
'default',
'type',
'choices',
'help',
'metavar'
]
return [(name, getattr(self, name)) for name in names]
def __call__(self, parser, namespace, values, option_string=None):
raise NotImplementedError(_('.__call__() not defined'))
class StoreAction(Action):
def __init__(self,
option_strings,
dest,
nargs=None,
const=None,
default=None,
type=None,
choices=None,
required=False,
help=None,
metavar=None):
if nargs == 0:
raise ValueError('nargs must be > 0')
if const is not None and nargs != OPTIONAL:
raise ValueError('nargs must be %r to supply const' % OPTIONAL)
super(StoreAction, self).__init__(
option_strings=option_strings,
dest=dest,
nargs=nargs,
const=const,
default=default,
type=type,
choices=choices,
required=required,
help=help,
metavar=metavar)
def __call__(self, parser, namespace, values, option_string=None):
setattr(namespace, self.dest, values)
class StoreConstAction(Action):
def __init__(self,
option_strings,
dest,
const,
default=None,
required=False,
help=None,
metavar=None):
super(StoreConstAction, self).__init__(
option_strings=option_strings,
dest=dest,
nargs=0,
const=const,
default=default,
required=required,
help=help)
def __call__(self, parser, namespace, values, option_string=None):
setattr(namespace, self.dest, self.const)
class StoreTrueAction(StoreConstAction):
def __init__(self,
option_strings,
dest,
default=False,
required=False,
help=None):
super(StoreTrueAction, self).__init__(
option_strings=option_strings,
dest=dest,
const=True,
default=default,
required=required,
help=help)
class StoreFalseAction(StoreConstAction):
def __init__(self,
option_strings,
dest,
default=True,
required=False,
help=None):
super(StoreFalseAction, self).__init__(
option_strings=option_strings,
dest=dest,
const=False,
default=default,
required=required,
help=help)
class AppendAction(Action):
def __init__(self,
option_strings,
dest,
nargs=None,
const=None,
default=None,
type=None,
choices=None,
required=False,
help=None,
metavar=None):
if nargs == 0:
raise ValueError('nargs must be > 0')
if const is not None and nargs != OPTIONAL:
raise ValueError('nargs must be %r to supply const' % OPTIONAL)
super(AppendAction, self).__init__(
option_strings=option_strings,
dest=dest,
nargs=nargs,
const=const,
default=default,
type=type,
choices=choices,
required=required,
help=help,
metavar=metavar)
def __call__(self, parser, namespace, values, option_string=None):
_ensure_value(namespace, self.dest, []).append(values)
class AppendConstAction(Action):
def __init__(self,
option_strings,
dest,
const,
default=None,
required=False,
help=None,
metavar=None):
super(AppendConstAction, self).__init__(
option_strings=option_strings,
dest=dest,
nargs=0,
const=const,
default=default,
required=required,
help=help,
metavar=metavar)
def __call__(self, parser, namespace, values, option_string=None):
_ensure_value(namespace, self.dest, []).append(self.const)
class CountAction(Action):
def __init__(self,
option_strings,
dest,
default=None,
required=False,
help=None):
super(CountAction, self).__init__(
option_strings=option_strings,
dest=dest,
nargs=0,
default=default,
required=required,
help=help)
def __call__(self, parser, namespace, values, option_string=None):
new_count = _ensure_value(namespace, self.dest, 0) + 1
setattr(namespace, self.dest, new_count)
class HelpAction(Action):
def __init__(self,
option_strings,
dest,
help=None):
super(HelpAction, self).__init__(
option_strings=option_strings,
dest=SUPPRESS,
nargs=0,
help=help)
def __call__(self, parser, namespace, values, option_string=None):
parser.print_help()
parser.exit()
class VersionAction(Action):
def __init__(self,
option_strings,
dest,
help=None):
super(VersionAction, self).__init__(
option_strings=option_strings,
dest=SUPPRESS,
nargs=0,
help=help)
def __call__(self, parser, namespace, values, option_string=None):
parser.print_version()
parser.exit()
class SubParsersAction(Action):
def __init__(self,
option_strings,
prog,
parser_class,
dest=SUPPRESS,
help=None,
metavar=None):
self._prog_prefix = prog
self._parser_class = parser_class
self._name_parser_map = {}
super(SubParsersAction, self).__init__(
option_strings=option_strings,
dest=dest,
nargs=PARSER,
choices=self._name_parser_map,
help=help,
metavar=metavar)
def add_parser(self, name, **kwargs):
if kwargs.get('prog') is None:
kwargs['prog'] = '%s %s' % (self._prog_prefix, name)
parser = self._parser_class(**kwargs)
self._name_parser_map[name] = parser
return parser
def __call__(self, parser, namespace, values, option_string=None):
parser_name = values[0]
arg_strings = values[1:]
# set the parser name if requested
if self.dest is not SUPPRESS:
setattr(namespace, self.dest, parser_name)
# select the parser
try:
parser = self._name_parser_map[parser_name]
except KeyError:
tup = parser_name, ', '.join(self._name_parser_map)
msg = _('unknown parser %r (choices: %s)' % tup)
raise ArgumentError(self, msg)
# parse all the remaining options into the namespace
parser.parse_args(arg_strings, namespace)
# ==============
# Type classes
# ==============
class FileType(object):
def __init__(self, mode='r', bufsize=None):
self._mode = mode
self._bufsize = bufsize
def __call__(self, string):
# the special argument "-" means sys.std{in,out}
if string == '-':
if self._mode == 'r':
return _sys.stdin
elif self._mode == 'w':
return _sys.stdout
else:
msg = _('argument "-" with mode %r' % self._mode)
raise ValueError(msg)
# all other arguments are used as file names
if self._bufsize:
return open(string, self._mode, self._bufsize)
else:
return open(string, self._mode)
# ===========================
# Optional and Positional Parsing
# ===========================
class Namespace(_AttributeHolder):
def __init__(self, **kwargs):
for name, value in kwargs.iteritems():
setattr(self, name, value)
def __eq__(self, other):
return vars(self) == vars(other)
def __ne__(self, other):
return not (self == other)
class _ActionsContainer(object):
def __init__(self,
description,
conflict_handler):
superinit = super(_ActionsContainer, self).__init__
superinit(description=description)
self.description = description
self.conflict_handler = conflict_handler
# set up registries
self._registries = {}
# register actions
self.register('action', None, StoreAction)
self.register('action', 'store', StoreAction)
self.register('action', 'store_const', StoreConstAction)
self.register('action', 'store_true', StoreTrueAction)
self.register('action', 'store_false', StoreFalseAction)
self.register('action', 'append', AppendAction)
self.register('action', 'append_const', AppendConstAction)
self.register('action', 'count', CountAction)
self.register('action', 'help', HelpAction)
self.register('action', 'version', VersionAction)
self.register('action', 'parsers', SubParsersAction)
# raise an exception if the conflict handler is invalid
self._get_handler()
# action storage
self._optional_actions_list = []
self._positional_actions_list = []
self._short_option_strings = {}
self._long_option_strings = {}
# ====================
# Registration methods
# ====================
def register(self, registry_name, value, object):
registry = self._registries.setdefault(registry_name, {})
registry[value] = object
def _registry_get(self, registry_name, value, default=None):
return self._registries[registry_name].get(value, default)
# =======================
# Adding argument actions
# =======================
def add_argument(self, *args, **kwargs):
"""
add_argument(dest, ..., name=value, ...)
add_argument(option_string, option_string, ..., name=value, ...)
"""
# type='outfile' is deprecated
if kwargs.get('type') == 'outfile':
import warnings
msg = _("use type=FileType('w') instead of type='outfile'")
warnings.warn(msg, DeprecationWarning)
# if no positional args are supplied or only one is supplied and
# it doesn't look like an option string, parse a positional
# argument
if not args or len(args) == 1 and args[0][0] != '-':
kwargs = self._get_positional_kwargs(*args, **kwargs)
# otherwise, we're adding an optional argument
else:
kwargs = self._get_optional_kwargs(*args, **kwargs)
# create the action object, and add it to the parser
action_class = self._pop_action_class(kwargs)
action = action_class(**kwargs)
return self._add_action(action)
def _add_action(self, action):
# resolve any conflicts
self._check_conflict(action)
# add to optional or positional list
if action.option_strings:
self._optional_actions_list.append(action)
else:
self._positional_actions_list.append(action)
action.container = self
# index the action by any option strings it has
for option_string in action.option_strings:
if option_string.startswith('--'):
self._long_option_strings[option_string] = action
else:
self._short_option_strings[option_string] = action
# return the created action
return action
def _add_container_actions(self, container):
for action in container._optional_actions_list:
self._add_action(action)
for action in container._positional_actions_list:
self._add_action(action)
def _get_positional_kwargs(self, dest, **kwargs):
# make sure required is not specified
if 'required' in kwargs:
msg = _("'required' is an invalid argument for positionals")
raise TypeError(msg)
# return the keyword arguments with no option strings
return dict(kwargs, dest=dest, option_strings=[])
def _get_optional_kwargs(self, *args, **kwargs):
# determine short and long option strings
option_strings = list(args)
short_option_strings = []
long_option_strings = []
for option_string in option_strings:
# error on one-or-fewer-character option strings
if len(option_string) < 2:
msg = _('invalid option string %r: '
'must be at least two characters long')
raise ValueError(msg % option_string)
# two-character option strings should be a dash and a character
elif len(option_string) == 2:
if option_string[0] != '-' or option_string[1] == '-':
msg = _('invalid short option string %r: must be of '
'the form -x, (x any non-dash char)')
raise ValueError(msg % option_string)
short_option_strings.append(option_string)
# three-or-more-character option strings start with two dashes
else:
if option_string[0:2] != '--' or option_string[2] == '-':
msg = _('invalid long option string %r: must start '
'with --, followed by non-dash')
raise ValueError(msg % option_string)
long_option_strings.append(option_string)
# infer destination, '--foo-bar' -> 'foo_bar' and '-x' -> 'x'
dest = kwargs.pop('dest', None)
if dest is None:
if long_option_strings:
dest = long_option_strings[0][2:].replace('-', '_')
else:
dest = short_option_strings[0][1:]
# return the updated keyword arguments
return dict(kwargs, dest=dest, option_strings=option_strings)
def _split_option_strings(self, option_strings):
# return the option strings, split into short and long
return short_option_strings, long_option_strings
def _pop_action_class(self, kwargs, default=None):
action = kwargs.pop('action', default)
return self._registry_get('action', action, action)
def _get_handler(self):
# determine function from conflict handler string
handler_func_name = '_handle_conflict_%s' % self.conflict_handler
try:
return getattr(self, handler_func_name)
except AttributeError:
msg = _('invalid conflict_resolution value: %r')
raise ValueError(msg % self.conflict_handler)
def _check_conflict(self, action):
# find all options that conflict with this option
confl_optionals = []
for option_string in action.option_strings:
if option_string in self._short_option_strings:
confl_optional = self._short_option_strings[option_string]
confl_optionals.append((option_string, confl_optional))
elif option_string in self._long_option_strings:
confl_optional = self._long_option_strings[option_string]
confl_optionals.append((option_string, confl_optional))
# resolve any conflicts
if confl_optionals:
conflict_handler = self._get_handler()
conflict_handler(action, confl_optionals)
def _handle_conflict_error(self, action, conflicting_actions):
message = _('conflicting option string(s): %s')
conflict_string = ', '.join(option_string
for option_string, action
in conflicting_actions)
raise ArgumentError(action, message % conflict_string)
def _handle_conflict_resolve(self, action, conflicting_actions):
# remove all conflicting options
for option_string, action in conflicting_actions:
# remove the conflicting option
action.option_strings.remove(option_string)
self._short_option_strings.pop(option_string, None)
self._long_option_strings.pop(option_string, None)
# if the option now has no option string, remove it from the
# container holding it
if not action.option_strings:
action.container._optional_actions_list.remove(action)
class ArgumentGroup(_ActionsContainer):
def __init__(self, container, title=None, description=None, **kwargs):
# add any missing keyword arguments by checking the container
update = kwargs.setdefault
update('conflict_handler', container.conflict_handler)
superinit = super(ArgumentGroup, self).__init__
superinit(description=description, **kwargs)
self.title = title
self._registries = container._registries
self._short_option_strings = container._short_option_strings
self._long_option_strings = container._long_option_strings
class ArgumentParser(_AttributeHolder, _ActionsContainer):
def __init__(self,
prog=None,
usage=None,
description=None,
epilog=None,
version=None,
parents=[],
argument_group_class=ArgumentGroup,
formatter_class=HelpFormatter,
conflict_handler='error',
add_help=True):
superinit = super(ArgumentParser, self).__init__
superinit(description=description,
conflict_handler=conflict_handler)
# default setting for prog
if prog is None:
prog = _os.path.basename(_sys.argv[0])
self.prog = prog
self.usage = usage
self.epilog = epilog
self.version = version
self.argument_group_class = argument_group_class
self.formatter_class = formatter_class
self.add_help = add_help
self._has_subparsers = False
self._optionals_groups = []
self._defaults = {}
# register types
def identity(string):
return string
def outfile(string):
if string == '-':
return _sys.stdout
else:
return open(string, 'w')
self.register('type', None, identity)
self.register('type', 'outfile', outfile)
# add help and version arguments if necessary
if self.add_help:
self._add_help_argument()
if self.version:
self._add_version_argument()
# add parent arguments and defaults
for parent in parents:
self._add_container_actions(parent)
try:
defaults = parent._defaults
except AttributeError:
pass
else:
self._defaults.update(defaults)
# determines whether an "option" looks like a negative number
self._negative_number_matcher = _re.compile(r'^-\d+|-\d*.\d+$')
# =======================
# Pretty __repr__ methods
# =======================
def _get_kwargs(self):
names = [
'prog',
'usage',
'description',
'version',
'argument_group_class',
'formatter_class',
'conflict_handler',
'add_help',
]
return [(name, getattr(self, name)) for name in names]
# ==================================
# Namespace default settings methods
# ==================================
def set_defaults(self, **kwargs):
self._defaults.update(kwargs)
# ==================================
# Optional/Positional adding methods
# ==================================
def add_argument_group(self, *args, **kwargs):
group = self.argument_group_class(self, *args, **kwargs)
self._optionals_groups.append(group)
return group
def add_subparsers(self, **kwargs):
if self._has_subparsers:
self.error(_('cannot have multiple subparser arguments'))
# add the parser class to the arguments if it's not present
kwargs.setdefault('parser_class', type(self))
# prog defaults to the usage message of this parser, skipping
# optional arguments and with no "usage:" prefix
if kwargs.get('prog') is None:
formatter = self._get_formatter()
formatter.add_usage(self.usage, [],
self._positional_actions_list, '')
kwargs['prog'] = formatter.format_help().strip()
# create the parsers action and add it to the positionals list
parsers_class = self._pop_action_class(kwargs, 'parsers')
action = parsers_class(option_strings=[], **kwargs)
self._positional_actions_list.append(action)
self._has_subparsers = True
# return the created parsers action
return action
def _add_container_actions(self, container):
super(ArgumentParser, self)._add_container_actions(container)
try:
groups = container._optionals_groups
except AttributeError:
pass
else:
for group in groups:
new_group = self.add_argument_group(
title=group.title,
description=group.description,
conflict_handler=group.conflict_handler)
new_group._add_container_actions(group)
def _get_all_optionals(self):
optionals = []
optionals.extend(self._optional_actions_list)
for optionals_group in self._optionals_groups:
optionals.extend(optionals_group._optional_actions_list)
return optionals
def _add_help_argument(self):
self.add_argument('-h', '--help', action='help',
help=_('show this help message and exit'))
def _add_version_argument(self):
self.add_argument('-v', '--version', action='version',
help=_("show program's version number and exit"))
# =====================================
# Command line argument parsing methods
# =====================================
def parse_args(self, args=None, namespace=None):
# args default to the system args
if args is None:
args = _sys.argv[1:]
# default Namespace built from parser defaults
if namespace is None:
namespace = Namespace()
# add any action defaults that aren't present
actions = self._get_all_optionals() + self._positional_actions_list
for action in actions:
if action.dest is not SUPPRESS:
if not hasattr(namespace, action.dest):
if action.default is not SUPPRESS:
default = action.default
if isinstance(action.default, basestring):
default = self._get_value(action, default)
setattr(namespace, action.dest, default)
# add any parser defaults that aren't present
for dest, value in self._defaults.iteritems():
if not hasattr(namespace, dest):
setattr(namespace, dest, value)
# parse the arguments and exit if there are any errors
try:
result = self._parse_args(args, namespace)
except ArgumentError, err:
self.error(str(err))
# make sure all required optionals are present
for action in self._get_all_optionals():
if action.required:
if getattr(result, action.dest, None) is None:
opt_strs = '/'.join(action.option_strings)
msg = _('option %s is required' % opt_strs)
self.error(msg)
# return the parsed arguments
return result
def _parse_args(self, arg_strings, namespace):
# find all option indices, and determine the arg_string_pattern
# which has an 'O' if there is an option at an index,
# an 'A' if there is an argument, or a '-' if there is a '--'
option_string_indices = set()
arg_string_pattern_parts = []
arg_strings_iter = iter(arg_strings)
for i, arg_string in enumerate(arg_strings_iter):
# all args after -- are non-options
if arg_string == '--':
arg_string_pattern_parts.append('-')
for arg_string in arg_strings_iter:
arg_string_pattern_parts.append('A')
# otherwise, add the arg to the arg strings
# and note the index if it was an option
else:
if self._looks_like_option(arg_string):
option_string_indices.add(i)
pattern = 'O'
else:
pattern = 'A'
arg_string_pattern_parts.append(pattern)
# join the pieces together to form the pattern
arg_strings_pattern = ''.join(arg_string_pattern_parts)
# converts arg strings to the appropriate and then takes the action
def take_action(action, argument_strings, option_string=None):
argument_values = self._get_values(action, argument_strings)
action(self, namespace, argument_values, option_string)
# function to convert arg_strings into an optional action
def consume_optional(start_index):
# determine the optional action and parse any explicit
# argument out of the option string
option_string = arg_strings[start_index]
parse = self._parse_optional
action, option_string, explicit_arg = parse(option_string)
# if we found no optional action, raise an error
if action is None:
self.error(_('no such option: %s') % option_string)
# if there is an explicit argument, try to match the
# optional's string arguments to only this
match_argument = self._match_argument
if explicit_arg is not None:
arg_count = match_argument(action, 'A')
if arg_count != 1:
msg = _('ignored explicit argument %r') % explicit_arg
raise ArgumentError(action, msg)
stop = start_index + 1
args = [explicit_arg]
# if there is no explicit argument, try to match the
# optional's string arguments with the following strings
else:
start = start_index + 1
selected_patterns = arg_strings_pattern[start:]
arg_count = match_argument(action, selected_patterns)
stop = start + arg_count
args = arg_strings[start:stop]
# add the Optional to the list and return the index at which
# the Optional's string args stopped
take_action(action, args, option_string)
return stop
# the list of Positionals left to be parsed; this is modified
# by consume_positionals()
positionals = list(self._positional_actions_list)
# function to convert arg_strings into positional actions
def consume_positionals(start_index):
# match as many Positionals as possible
match_partial = self._match_arguments_partial
selected_pattern = arg_strings_pattern[start_index:]
arg_counts = match_partial(positionals, selected_pattern)
# slice off the appropriate arg strings for each Positional
# and add the Positional and its args to the list
for action, arg_count in zip(positionals, arg_counts):
args = arg_strings[start_index: start_index + arg_count]
start_index += arg_count
take_action(action, args)
# slice off the Positionals that we just parsed and return the
# index at which the Positionals' string args stopped
positionals[:] = positionals[len(arg_counts):]
return start_index
# consume Positionals and Optionals alternately, until we have
# passed the last option string
start_index = 0
if option_string_indices:
max_option_string_index = max(option_string_indices)
else:
max_option_string_index = -1
while start_index <= max_option_string_index:
# consume any Positionals preceding the next option
next_option_string_index = min(
index
for index in option_string_indices
if index >= start_index)
if start_index != next_option_string_index:
positionals_end_index = consume_positionals(start_index)
# only try to parse the next optional if we didn't consume
# the option string during the positionals parsing
if positionals_end_index > start_index:
start_index = positionals_end_index
continue
else:
start_index = positionals_end_index
# if we consumed all the positionals we could and we're not
# at the index of an option string, there were unparseable
# arguments
if start_index not in option_string_indices:
msg = _('extra arguments found: %s')
extras = arg_strings[start_index:next_option_string_index]
self.error(msg % ' '.join(extras))
# consume the next optional and any arguments for it
start_index = consume_optional(start_index)
# consume any positionals following the last Optional
stop_index = consume_positionals(start_index)
# if we didn't consume all the argument strings, there were too
# many supplied
if stop_index != len(arg_strings):
extras = arg_strings[stop_index:]
self.error(_('extra arguments found: %s') % ' '.join(extras))
# if we didn't use all the Positional objects, there were too few
# arg strings supplied.
if positionals:
self.error(_('too few arguments'))
# return the updated namespace
return namespace
def _looks_like_option(self, arg_string):
# if it doesn't start with a '-', it's meant to be positional
if not arg_string.startswith('-'):
return False
# if it's just a single dash, it's meant to be positional
if arg_string == '-':
return False
# if it starts with two dashes, it's meant to be an option
if arg_string.startswith('--'):
return True
# if it's a valid short option, it's meant to be an option
if arg_string[:2] in self._short_option_strings:
return True
# if it looks like a negative number, it's meant to be positional
if self._negative_number_matcher.match(arg_string):
return False
# otherwise, it looks like an option (but it's not in the parser)
return True
def _match_argument(self, action, arg_strings_pattern):
# match the pattern for this action to the arg strings
nargs_pattern = self._get_nargs_pattern(action)
match = _re.match(nargs_pattern, arg_strings_pattern)
# raise an exception if we weren't able to find a match
if match is None:
nargs_errors = {
None:_('expected one argument'),
OPTIONAL:_('expected at most one argument'),
ONE_OR_MORE:_('expected at least one argument')
}
default = _('expected %s argument(s)') % action.nargs
msg = nargs_errors.get(action.nargs, default)
raise ArgumentError(action, msg)
# return the number of arguments matched
return len(match.group(1))
def _match_arguments_partial(self, actions, arg_strings_pattern):
# progressively shorten the actions list by slicing off the
# final actions until we find a match
result = []
for i in xrange(len(actions), 0, -1):
actions_slice = actions[:i]
pattern = ''.join(self._get_nargs_pattern(action)
for action in actions_slice)
match = _re.match(pattern, arg_strings_pattern)
if match is not None:
result.extend(len(string) for string in match.groups())
break
# return the list of arg string counts
return result
def _parse_optional(self, option_string):
# for long option strings, split off '=' arguments if necessary
# and call _match_long_option_string()
if option_string.startswith('--'):
if '=' in option_string:
option_string, explicit_arg = option_string.split('=')
else:
explicit_arg = None
action = self._match_long_option_string(option_string)
# for short option strings, split off the characters past 1 if
# necessary and check the _short_option_strings dict
else:
if len(option_string) > 2:
explicit_arg = option_string[2:]
option_string = option_string[:2]
else:
explicit_arg = None
try:
action = self._short_option_strings[option_string]
except KeyError:
action = None
# otherwise return the optional and the explicit string argument
return action, option_string, explicit_arg
def _match_long_option_string(self, option_string):
long_opts = self._long_option_strings
# short path: just look it up in the table
try:
action = long_opts[option_string]
# long path: check all words with the argument string as a prefix
except KeyError:
possible_option_strings = [
word for word in long_opts if word.startswith(option_string)
]
# see if there is exactly one possible string
try:
option_string, = possible_option_strings
# if there are zero or multiple matches, report errors
except ValueError:
if possible_option_strings:
tup = option_string, ', '.join(possible_option_strings)
self.error(_('ambiguous option: %s (%s?)') % tup)
else:
self.error(_('no such option: %s') % option_string)
# if there was exactly one match, return the Optional for it
else:
action = long_opts[option_string]
return action
def _get_nargs_pattern(self, action):
# in all examples below, we have to allow for '--' args
# which are represented as '-' in the pattern
nargs = action.nargs
# the default (None) is assumed to be a single argument
if nargs is None:
nargs_pattern = '(-*A-*)'
# allow zero or one arguments
elif nargs == OPTIONAL:
nargs_pattern = '(-*A?-*)'
# allow zero or more arguments
elif nargs == ZERO_OR_MORE:
nargs_pattern = '(-*[A-]*)'
# allow one or more arguments
elif nargs == ONE_OR_MORE:
nargs_pattern = '(-*A[A-]*)'
# allow one argument followed by any number of options or arguments
elif nargs is PARSER:
nargs_pattern = '(-*A[-AO]*)'
# all others should be integers
else:
nargs_pattern = '(-*%s-*)' % '-*'.join('A' * nargs)
# if this is an optional action, -- is not allowed
if action.option_strings:
nargs_pattern = nargs_pattern.replace('-*', '')
nargs_pattern = nargs_pattern.replace('-', '')
# return the pattern
return nargs_pattern
# ========================
# Value conversion methods
# ========================
def _get_values(self, action, arg_strings):
# for everything but PARSER args, strip out '--'
if action.nargs is not PARSER:
arg_strings = [s for s in arg_strings if s != '--']
# optional argument produces a default when not present
if not arg_strings and action.nargs == OPTIONAL:
if action.option_strings:
value = action.const
else:
value = action.default
if isinstance(value, basestring):
value = self._get_value(action, value)
self._check_value(action, value)
# when nargs='*' on a positional, if there were no command-line
# args, use the default if it is anything other than None
elif (not arg_strings and action.nargs == ZERO_OR_MORE and
not action.option_strings):
if action.default is not None:
value = action.default
else:
value = arg_strings
self._check_value(action, value)
# single argument or optional argument produces a single value
elif len(arg_strings) == 1 and action.nargs in [None, OPTIONAL]:
arg_string, = arg_strings
value = self._get_value(action, arg_string)
self._check_value(action, value)
# PARSER arguments convert all values, but check only the first
elif action.nargs is PARSER:
value = list(self._get_value(action, v) for v in arg_strings)
self._check_value(action, value[0])
# all other types of nargs produce a list
else:
value = list(self._get_value(action, v) for v in arg_strings)
for v in value:
self._check_value(action, v)
# return the converted value
return value
def _get_value(self, action, arg_string):
type_func = self._registry_get('type', action.type, action.type)
if not callable(type_func):
msg = _('%r is not callable')
raise ArgumentError(action, msg % type_func)
# convert the value to the appropriate type
try:
result = type_func(arg_string)
# TypeErrors or ValueErrors indicate errors
except (TypeError, ValueError):
name = getattr(action.type, '__name__', repr(action.type))
msg = _('invalid %s value: %r')
raise ArgumentError(action, msg % (name, arg_string))
# return the converted value
return result
def _check_value(self, action, value):
# converted value must be one of the choices (if specified)
if action.choices is not None and value not in action.choices:
tup = value, ', '.join(map(repr, action.choices))
msg = _('invalid choice: %r (choose from %s)') % tup
raise ArgumentError(action, msg)
# =======================
# Help-formatting methods
# =======================
def format_usage(self):
formatter = self._get_formatter()
formatter.add_usage(self.usage,
self._get_all_optionals(),
self._positional_actions_list)
return formatter.format_help()
def format_help(self):
formatter = self._get_formatter()
# usage
formatter.add_usage(self.usage,
self._get_all_optionals(),
self._positional_actions_list)
# description
formatter.add_text(self.description)
# positionals
formatter.start_section(_('positional arguments'))
formatter.add_arguments(self._positional_actions_list)
formatter.end_section()
# optionals
formatter.start_section(_('optional arguments'))
formatter.add_arguments(self._optional_actions_list)
for optionals_group in self._optionals_groups:
formatter.start_section(optionals_group.title)
formatter.add_text(optionals_group.description)
formatter.add_arguments(optionals_group._optional_actions_list)
formatter.end_section()
formatter.end_section()
# epilog
formatter.add_text(self.epilog)
# determine help from format above
return formatter.format_help()
def format_version(self):
formatter = self._get_formatter()
formatter.add_text(self.version)
return formatter.format_help()
def _get_formatter(self):
return self.formatter_class(prog=self.prog)
# =====================
# Help-printing methods
# =====================
def print_usage(self, file=None):
self._print_message(self.format_usage(), file)
def print_help(self, file=None):
self._print_message(self.format_help(), file)
def print_version(self, file=None):
self._print_message(self.format_version(), file)
def _print_message(self, message, file=None):
if message:
if file is None:
file = _sys.stderr
file.write(message)
# ===============
# Exiting methods
# ===============
def exit(self, status=0, message=None):
if message:
_sys.stderr.write(message)
_sys.exit(status)
def error(self, message):
"""error(message: string)
Prints a usage message incorporating the message to stderr and
exits.
If you override this in a subclass, it should not return -- it
should either exit or raise an exception.
"""
self.print_usage(_sys.stderr)
self.exit(2, _('%s: error: %s\n') % (self.prog, message))
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