| # Copyright 2006-2009 Steven J. Bethard <steven.bethard@gmail.com>. | |
| # | |
| # Licensed under the Apache License, Version 2.0 (the "License"); you may not | |
| # use this file except in compliance with the License. You may obtain a copy | |
| # of the License at | |
| # | |
| # http://www.apache.org/licenses/LICENSE-2.0 | |
| # | |
| # Unless required by applicable law or agreed to in writing, software | |
| # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT | |
| # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the | |
| # License for the specific language governing permissions and limitations | |
| # under the License. | |
| """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', | |
| 'Namespace', | |
| 'Action', | |
| 'FileType', | |
| 'HelpFormatter', | |
| 'RawDescriptionHelpFormatter', | |
| 'RawTextHelpFormatter', | |
| 'ArgumentDefaultsHelpFormatter', | |
| ] | |
| 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 _ | |
| try: | |
| _set = set | |
| except NameError: | |
| from sets import Set as _set | |
| try: | |
| _basestring = basestring | |
| except NameError: | |
| _basestring = str | |
| try: | |
| _sorted = sorted | |
| except NameError: | |
| def _sorted(iterable, reverse=False): | |
| result = list(iterable) | |
| result.sort() | |
| if reverse: | |
| result.reverse() | |
| return result | |
| def _callable(obj): | |
| return hasattr(obj, '__call__') or hasattr(obj, '__bases__') | |
| # silence Python 2.6 buggy warnings about Exception.message | |
| if _sys.version_info[:2] == (2, 6): | |
| import warnings | |
| warnings.filterwarnings( | |
| action='ignore', | |
| message='BaseException.message has been deprecated as of Python 2.6', | |
| category=DeprecationWarning, | |
| module='argparse') | |
| 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: | |
| inserts[start] = '[' | |
| inserts[end] = ']' | |
| 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: | |
| choice_strs = [str(choice) for choice in action.choices] | |
| result = '{%s}' % ','.join(choice_strs) | |
| else: | |
| result = default_metavar | |
| def format(tuple_size): | |
| if isinstance(result, tuple): | |
| return result | |
| else: | |
| return (result, ) * tuple_size | |
| return format | |
| def _format_args(self, action, default_metavar): | |
| get_metavar = self._metavar_formatter(action, default_metavar) | |
| if action.nargs is None: | |
| result = '%s' % get_metavar(1) | |
| elif action.nargs == OPTIONAL: | |
| result = '[%s]' % get_metavar(1) | |
| elif action.nargs == ZERO_OR_MORE: | |
| result = '[%s [%s ...]]' % get_metavar(2) | |
| elif action.nargs == ONE_OR_MORE: | |
| result = '%s [%s ...]' % get_metavar(2) | |
| elif action.nargs == REMAINDER: | |
| result = '...' | |
| elif action.nargs == PARSER: | |
| result = '%s ...' % get_metavar(1) | |
| else: | |
| formats = ['%s' for _ in range(action.nargs)] | |
| result = ' '.join(formats) % get_metavar(action.nargs) | |
| return result | |
| def _expand_help(self, action): | |
| params = dict(vars(action), prog=self._prog) | |
| for name in list(params): | |
| if params[name] is SUPPRESS: | |
| del params[name] | |
| for name in list(params): | |
| if hasattr(params[name], '__name__'): | |
| params[name] = params[name].__name__ | |
| if params.get('choices') is not None: | |
| choices_str = ', '.join([str(c) for c in params['choices']]) | |
| params['choices'] = choices_str | |
| return self._get_help_string(action) % params | |
| def _iter_indented_subactions(self, action): | |
| try: | |
| get_subactions = action._get_subactions | |
| except AttributeError: | |
| pass | |
| else: | |
| self._indent() | |
| for subaction in get_subactions(): | |
| yield subaction | |
| self._dedent() | |
| 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) | |
| def _get_help_string(self, action): | |
| return action.help | |
| class RawDescriptionHelpFormatter(HelpFormatter): | |
| """Help message formatter which retains any formatting in descriptions. | |
| Only the name of this class is considered a public API. All the methods | |
| provided by the class are considered an implementation detail. | |
| """ | |
| def _fill_text(self, text, width, indent): | |
| return ''.join([indent + line for line in text.splitlines(True)]) | |
| class RawTextHelpFormatter(RawDescriptionHelpFormatter): | |
| """Help message formatter which retains formatting of all help text. | |
| Only the name of this class is considered a public API. All the methods | |
| provided by the class are considered an implementation detail. | |
| """ | |
| def _split_lines(self, text, width): | |
| return text.splitlines() | |
| class ArgumentDefaultsHelpFormatter(HelpFormatter): | |
| """Help message formatter which adds default values to argument help. | |
| Only the name of this class is considered a public API. All the methods | |
| provided by the class are considered an implementation detail. | |
| """ | |
| def _get_help_string(self, action): | |
| help = action.help | |
| if '%(default)' not in action.help: | |
| if action.default is not SUPPRESS: | |
| defaulting_nargs = [OPTIONAL, ZERO_OR_MORE] | |
| if action.option_strings or action.nargs in defaulting_nargs: | |
| help += ' (default: %(default)s)' | |
| return help | |
| # ===================== | |
| # Options and Arguments | |
| # ===================== | |
| def _get_action_name(argument): | |
| if argument is None: | |
| return None | |
| elif argument.option_strings: | |
| return '/'.join(argument.option_strings) | |
| elif argument.metavar not in (None, SUPPRESS): | |
| return argument.metavar | |
| elif argument.dest not in (None, SUPPRESS): | |
| return argument.dest | |
| else: | |
| return None | |
| class ArgumentError(Exception): | |
| """An error from 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): | |
| self.argument_name = _get_action_name(argument) | |
| 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) | |
| class ArgumentTypeError(Exception): | |
| """An error from trying to convert a command line string to a type.""" | |
| pass | |
| # ============== | |
| # Action classes | |
| # ============== | |
| class Action(_AttributeHolder): | |
| """Information about how to convert command line strings to Python objects. | |
| Action objects are used by an ArgumentParser to represent the information | |
| needed to parse a single argument from one or more strings from the | |
| command line. The keyword arguments to the Action constructor are also | |
| all attributes of Action instances. | |
| 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 for store actions must be > 0; if you ' | |
| 'have nothing to store, actions such as store ' | |
| 'true or store const may be more appropriate') | |
| 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 for append actions must be > 0; if arg ' | |
| 'strings are not supplying the value to append, ' | |
| 'the append const action may be more appropriate') | |
| 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): | |
| items = _copy.copy(_ensure_value(namespace, self.dest, [])) | |
| items.append(values) | |
| setattr(namespace, self.dest, items) | |
| 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): | |
| items = _copy.copy(_ensure_value(namespace, self.dest, [])) | |
| items.append(self.const) | |
| setattr(namespace, self.dest, items) | |
| 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=SUPPRESS, | |
| default=SUPPRESS, | |
| help=None): | |
| super(_HelpAction, self).__init__( | |
| option_strings=option_strings, | |
| dest=dest, | |
| default=default, | |
| 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, | |
| version=None, | |
| dest=SUPPRESS, | |
| default=SUPPRESS, | |
| help=None): | |
| super(_VersionAction, self).__init__( | |
| option_strings=option_strings, | |
| dest=dest, | |
| default=default, | |
| nargs=0, | |
| help=help) | |
| self.version = version | |
| def __call__(self, parser, namespace, values, option_string=None): | |
| version = self.version | |
| if version is None: | |
| version = parser.version | |
| formatter = parser._get_formatter() | |
| formatter.add_text(version) | |
| parser.exit(message=formatter.format_help()) | |
| class _SubParsersAction(Action): | |
| class _ChoicesPseudoAction(Action): | |
| def __init__(self, name, help): | |
| sup = super(_SubParsersAction._ChoicesPseudoAction, self) | |
| sup.__init__(option_strings=[], dest=name, help=help) | |
| 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 = {} | |
| self._choices_actions = [] | |
| 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): | |
| # set prog from the existing prefix | |
| if kwargs.get('prog') is None: | |
| kwargs['prog'] = '%s %s' % (self._prog_prefix, name) | |
| # create a pseudo-action to hold the choice help | |
| if 'help' in kwargs: | |
| help = kwargs.pop('help') | |
| choice_action = self._ChoicesPseudoAction(name, help) | |
| self._choices_actions.append(choice_action) | |
| # create the parser and add it to the map | |
| parser = self._parser_class(**kwargs) | |
| self._name_parser_map[name] = parser | |
| return parser | |
| def _get_subactions(self): | |
| return self._choices_actions | |
| 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): | |
| """Factory for creating file object types | |
| Instances of FileType are typically passed as type= arguments to the | |
| ArgumentParser add_argument() method. | |
| Keyword Arguments: | |
| - mode -- A string indicating how the file is to be opened. Accepts the | |
| same values as the builtin open() function. | |
| - bufsize -- The file's desired buffer size. Accepts the same values as | |
| the builtin open() function. | |
| """ | |
| 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 'r' in self._mode: | |
| return _sys.stdin | |
| elif 'w' in self._mode: | |
| 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) | |
| def __repr__(self): | |
| args = [self._mode, self._bufsize] | |
| args_str = ', '.join([repr(arg) for arg in args if arg is not None]) | |
| return '%s(%s)' % (type(self).__name__, args_str) | |
| # =========================== | |
| # Optional and Positional Parsing | |
| # =========================== | |
| class Namespace(_AttributeHolder): | |
| """Simple object for storing attributes. | |
| Implements equality by attribute names and values, and provides a simple | |
| string representation. | |
| """ | |
| def __init__(self, **kwargs): | |
| for name in kwargs: | |
| setattr(self, name, kwargs[name]) | |
| def __eq__(self, other): | |
| return vars(self) == vars(other) | |
| def __ne__(self, other): | |
| return not (self == other) | |
| def __contains__(self, key): | |
| return key in self.__dict__ | |
| class _ActionsContainer(object): | |
| def __init__(self, | |
| description, | |
| prefix_chars, | |
| argument_default, | |
| conflict_handler): | |
| super(_ActionsContainer, self).__init__() | |
| self.description = description | |
| self.argument_default = argument_default | |
| self.prefix_chars = prefix_chars | |
| 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._actions = [] | |
| self._option_string_actions = {} | |
| # groups | |
| self._action_groups = [] | |
| self._mutually_exclusive_groups = [] | |
| # defaults storage | |
| self._defaults = {} | |
| # determines whether an "option" looks like a negative number | |
| self._negative_number_matcher = _re.compile(r'^-\d+$|^-\d*\.\d+$') | |
| # whether or not there are any optionals that look like negative | |
| # numbers -- uses a list so it can be shared and edited | |
| self._has_negative_number_optionals = [] | |
| # ==================== | |
| # 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) | |
| # ================================== | |
| # Namespace default accessor methods | |
| # ================================== | |
| def set_defaults(self, **kwargs): | |
| self._defaults.update(kwargs) | |
| # if these defaults match any existing arguments, replace | |
| # the previous default on the object with the new one | |
| for action in self._actions: | |
| if action.dest in kwargs: | |
| action.default = kwargs[action.dest] | |
| def get_default(self, dest): | |
| for action in self._actions: | |
| if action.dest == dest and action.default is not None: | |
| return action.default | |
| return self._defaults.get(dest, None) | |
| # ======================= | |
| # Adding argument actions | |
| # ======================= | |
| def add_argument(self, *args, **kwargs): | |
| """ | |
| add_argument(dest, ..., name=value, ...) | |
| add_argument(option_string, option_string, ..., name=value, ...) | |
| """ | |
| # if no positional args are supplied or only one is supplied and | |
| # it doesn't look like an option string, parse a positional | |
| # argument | |
| chars = self.prefix_chars | |
| if not args or len(args) == 1 and args[0][0] not in chars: | |
| if args and 'dest' in kwargs: | |
| raise ValueError('dest supplied twice for positional argument') | |
| kwargs = self._get_positional_kwargs(*args, **kwargs) | |
| # otherwise, we're adding an optional argument | |
| else: | |
| kwargs = self._get_optional_kwargs(*args, **kwargs) | |
| # if no default was supplied, use the parser-level default | |
| if 'default' not in kwargs: | |
| dest = kwargs['dest'] | |
| if dest in self._defaults: | |
| kwargs['default'] = self._defaults[dest] | |
| elif self.argument_default is not None: | |
| kwargs['default'] = self.argument_default | |
| # create the action object, and add it to the parser | |
| action_class = self._pop_action_class(kwargs) | |
| if not _callable(action_class): | |
| raise ValueError('unknown action "%s"' % action_class) | |
| action = action_class(**kwargs) | |
| # raise an error if the action type is not callable | |
| type_func = self._registry_get('type', action.type, action.type) | |
| if not _callable(type_func): | |
| raise ValueError('%r is not callable' % type_func) | |
| return self._add_action(action) | |
| def add_argument_group(self, *args, **kwargs): | |
| group = _ArgumentGroup(self, *args, **kwargs) | |
| self._action_groups.append(group) | |
| return group | |
| def add_mutually_exclusive_group(self, **kwargs): | |
| group = _MutuallyExclusiveGroup(self, **kwargs) | |
| self._mutually_exclusive_groups.append(group) | |
| return group | |
| def _add_action(self, action): | |
| # resolve any conflicts | |
| self._check_conflict(action) | |
| # add to actions list | |
| self._actions.append(action) | |
| action.container = self | |
| # index the action by any option strings it has | |
| for option_string in action.option_strings: | |
| self._option_string_actions[option_string] = action | |
| # set the flag if any option strings look like negative numbers | |
| for option_string in action.option_strings: | |
| if self._negative_number_matcher.match(option_string): | |
| if not self._has_negative_number_optionals: | |
| self._has_negative_number_optionals.append(True) | |
| # return the created action | |
| return action | |
| def _remove_action(self, action): | |
| self._actions.remove(action) | |
| def _add_container_actions(self, container): | |
| # collect groups by titles | |
| title_group_map = {} | |
| for group in self._action_groups: | |
| if group.title in title_group_map: | |
| msg = _('cannot merge actions - two groups are named %r') | |
| raise ValueError(msg % (group.title)) | |
| title_group_map[group.title] = group | |
| # map each action to its group | |
| group_map = {} | |
| for group in container._action_groups: | |
| # if a group with the title exists, use that, otherwise | |
| # create a new group matching the container's group | |
| if group.title not in title_group_map: | |
| title_group_map[group.title] = self.add_argument_group( | |
| title=group.title, | |
| description=group.description, | |
| conflict_handler=group.conflict_handler) | |
| # map the actions to their new group | |
| for action in group._group_actions: | |
| group_map[action] = title_group_map[group.title] | |
| # add container's mutually exclusive groups | |
| # NOTE: if add_mutually_exclusive_group ever gains title= and | |
| # description= then this code will need to be expanded as above | |
| for group in container._mutually_exclusive_groups: | |
| mutex_group = self.add_mutually_exclusive_group( | |
| required=group.required) | |
| # map the actions to their new mutex group | |
| for action in group._group_actions: | |
| group_map[action] = mutex_group | |
| # add all actions to this container or their group | |
| for action in container._actions: | |
| group_map.get(action, 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) | |
| # mark positional arguments as required if at least one is | |
| # always required | |
| if kwargs.get('nargs') not in [OPTIONAL, ZERO_OR_MORE]: | |
| kwargs['required'] = True | |
| if kwargs.get('nargs') == ZERO_OR_MORE and 'default' not in kwargs: | |
| kwargs['required'] = True | |
| # 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 = [] | |
| long_option_strings = [] | |
| for option_string in args: | |
| # error on strings that don't start with an appropriate prefix | |
| if not option_string[0] in self.prefix_chars: | |
| msg = _('invalid option string %r: ' | |
| 'must start with a character %r') | |
| tup = option_string, self.prefix_chars | |
| raise ValueError(msg % tup) | |
| # strings starting with two prefix characters are long options | |
| option_strings.append(option_string) | |
| if option_string[0] in self.prefix_chars: | |
| if len(option_string) > 1: | |
| if option_string[1] in self.prefix_chars: | |
| 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_option_string = long_option_strings[0] | |
| else: | |
| dest_option_string = option_strings[0] | |
| dest = dest_option_string.lstrip(self.prefix_chars) | |
| if not dest: | |
| msg = _('dest= is required for options like %r') | |
| raise ValueError(msg % option_string) | |
| dest = dest.replace('-', '_') | |
| # return the updated keyword arguments | |
| return dict(kwargs, dest=dest, option_strings=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._option_string_actions: | |
| confl_optional = self._option_string_actions[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._option_string_actions.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._remove_action(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) | |
| update('prefix_chars', container.prefix_chars) | |
| update('argument_default', container.argument_default) | |
| super_init = super(_ArgumentGroup, self).__init__ | |
| super_init(description=description, **kwargs) | |
| # group attributes | |
| self.title = title | |
| self._group_actions = [] | |
| # share most attributes with the container | |
| self._registries = container._registries | |
| self._actions = container._actions | |
| self._option_string_actions = container._option_string_actions | |
| self._defaults = container._defaults | |
| self._has_negative_number_optionals = \ | |
| container._has_negative_number_optionals | |
| def _add_action(self, action): | |
| action = super(_ArgumentGroup, self)._add_action(action) | |
| self._group_actions.append(action) | |
| return action | |
| def _remove_action(self, action): | |
| super(_ArgumentGroup, self)._remove_action(action) | |
| self._group_actions.remove(action) | |
| class _MutuallyExclusiveGroup(_ArgumentGroup): | |
| def __init__(self, container, required=False): | |
| super(_MutuallyExclusiveGroup, self).__init__(container) | |
| self.required = required | |
| self._container = container | |
| def _add_action(self, action): | |
| if action.required: | |
| msg = _('mutually exclusive arguments must be optional') | |
| raise ValueError(msg) | |
| action = self._container._add_action(action) | |
| self._group_actions.append(action) | |
| return action | |
| def _remove_action(self, action): | |
| self._container._remove_action(action) | |
| self._group_actions.remove(action) | |
| class ArgumentParser(_AttributeHolder, _ActionsContainer): | |
| """Object for parsing command line strings into Python objects. | |
| Keyword Arguments: | |
| - prog -- The name of the program (default: sys.argv[0]) | |
| - usage -- A usage message (default: auto-generated from arguments) | |
| - description -- A description of what the program does | |
| - epilog -- Text following the argument descriptions | |
| - parents -- Parsers whose arguments should be copied into this one | |
| - formatter_class -- HelpFormatter class for printing help messages | |
| - prefix_chars -- Characters that prefix optional arguments | |
| - fromfile_prefix_chars -- Characters that prefix files containing | |
| additional arguments | |
| - argument_default -- The default value for all arguments | |
| - conflict_handler -- String indicating how to handle conflicts | |
| - add_help -- Add a -h/-help option | |
| """ | |
| def __init__(self, | |
| prog=None, | |
| usage=None, | |
| description=None, | |
| epilog=None, | |
| version=None, | |
| parents=[], | |
| formatter_class=HelpFormatter, | |
| prefix_chars='-', | |
| fromfile_prefix_chars=None, | |
| argument_default=None, | |
| conflict_handler='error', | |
| add_help=True): | |
| if version is not None: | |
| import warnings | |
| warnings.warn( | |
| """The "version" argument to ArgumentParser is deprecated. """ | |
| """Please use """ | |
| """"add_argument(..., action='version', version="N", ...)" """ | |
| """instead""", DeprecationWarning) | |
| superinit = super(ArgumentParser, self).__init__ | |
| superinit(description=description, | |
| prefix_chars=prefix_chars, | |
| argument_default=argument_default, | |
| 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.formatter_class = formatter_class | |
| self.fromfile_prefix_chars = fromfile_prefix_chars | |
| self.add_help = add_help | |
| add_group = self.add_argument_group | |
| self._positionals = add_group(_('positional arguments')) | |
| self._optionals = add_group(_('optional arguments')) | |
| self._subparsers = None | |
| # register types | |
| def identity(string): | |
| return string | |
| self.register('type', None, identity) | |
| # add help and version arguments if necessary | |
| # (using explicit default to override global argument_default) | |
| if self.add_help: | |
| self.add_argument( | |
| '-h', '--help', action='help', default=SUPPRESS, | |
| help=_('show this help message and exit')) | |
| if self.version: | |
| self.add_argument( | |
| '-v', '--version', action='version', default=SUPPRESS, | |
| version=self.version, | |
| help=_("show program's version number and exit")) | |
| # 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) | |
| # ======================= | |
| # Pretty __repr__ methods | |
| # ======================= | |
| def _get_kwargs(self): | |
| names = [ | |
| 'prog', | |
| 'usage', | |
| 'description', | |
| 'version', | |
| 'formatter_class', | |
| 'conflict_handler', | |
| 'add_help', | |
| ] | |
| return [(name, getattr(self, name)) for name in names] | |
| # ================================== | |
| # Optional/Positional adding methods | |
| # ================================== | |
| def add_subparsers(self, **kwargs): | |
| if self._subparsers is not None: | |
| 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)) | |
| if 'title' in kwargs or 'description' in kwargs: | |
| title = _(kwargs.pop('title', 'subcommands')) | |
| description = _(kwargs.pop('description', None)) | |
| self._subparsers = self.add_argument_group(title, description) | |
| else: | |
| self._subparsers = self._positionals | |
| # 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() | |
| positionals = self._get_positional_actions() | |
| groups = self._mutually_exclusive_groups | |
| formatter.add_usage(self.usage, positionals, groups, '') | |
| 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._subparsers._add_action(action) | |
| # return the created parsers action | |
| return action | |
| def _add_action(self, action): | |
| if action.option_strings: | |
| self._optionals._add_action(action) | |
| else: | |
| self._positionals._add_action(action) | |
| return action | |
| def _get_optional_actions(self): | |
| return [action | |
| for action in self._actions | |
| if action.option_strings] | |
| def _get_positional_actions(self): | |
| return [action | |
| for action in self._actions | |
| if not action.option_strings] | |
| # ===================================== | |
| # Command line argument parsing methods | |
| # ===================================== | |
| def parse_args(self, args=None, namespace=None): | |
| args, argv = self.parse_known_args(args, namespace) | |
| if argv: | |
| msg = _('unrecognized arguments: %s') | |
| self.error(msg % ' '.join(argv)) | |
| return args | |
| def parse_known_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 | |
| for action in self._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 in self._defaults: | |
| if not hasattr(namespace, dest): | |
| setattr(namespace, dest, self._defaults[dest]) | |
| # parse the arguments and exit if there are any errors | |
| try: | |
| return self._parse_known_args(args, namespace) | |
| except ArgumentError: | |
| err = _sys.exc_info()[1] | |
| self.error(str(err)) | |
| def _parse_known_args(self, arg_strings, namespace): | |
| # replace arg strings that are file references | |
| if self.fromfile_prefix_chars is not None: | |
| arg_strings = self._read_args_from_files(arg_strings) | |
| # map all mutually exclusive arguments to the other arguments | |
| # they can't occur with | |
| action_conflicts = {} | |
| for mutex_group in self._mutually_exclusive_groups: | |
| group_actions = mutex_group._group_actions | |
| for i, mutex_action in enumerate(mutex_group._group_actions): | |
| conflicts = action_conflicts.setdefault(mutex_action, []) | |
| conflicts.extend(group_actions[:i]) | |
| conflicts.extend(group_actions[i + 1:]) | |
| # 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 = {} | |
| 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: | |
| option_tuple = self._parse_optional(arg_string) | |
| if option_tuple is None: | |
| pattern = 'A' | |
| else: | |
| option_string_indices[i] = option_tuple | |
| pattern = 'O' | |
| 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 | |
| seen_actions = _set() | |
| seen_non_default_actions = _set() | |
| def take_action(action, argument_strings, option_string=None): | |
| seen_actions.add(action) | |
| argument_values = self._get_values(action, argument_strings) | |
| # error if this argument is not allowed with other previously | |
| # seen arguments, assuming that actions that use the default | |
| # value don't really count as "present" | |
| if argument_values is not action.default: | |
| seen_non_default_actions.add(action) | |
| for conflict_action in action_conflicts.get(action, []): | |
| if conflict_action in seen_non_default_actions: | |
| msg = _('not allowed with argument %s') | |
| action_name = _get_action_name(conflict_action) | |
| raise ArgumentError(action, msg % action_name) | |
| # take the action if we didn't receive a SUPPRESS value | |
| # (e.g. from a default) | |
| if argument_values is not SUPPRESS: | |
| action(self, namespace, argument_values, option_string) | |
| # function to convert arg_strings into an optional action | |
| def consume_optional(start_index): | |
| # get the optional identified at this index | |
| option_tuple = option_string_indices[start_index] | |
| action, option_string, explicit_arg = option_tuple | |
| # identify additional optionals in the same arg string | |
| # (e.g. -xyz is the same as -x -y -z if no args are required) | |
| match_argument = self._match_argument | |
| action_tuples = [] | |
| while True: | |
| # if we found no optional action, skip it | |
| if action is None: | |
| extras.append(arg_strings[start_index]) | |
| return start_index + 1 | |
| # if there is an explicit argument, try to match the | |
| # optional's string arguments to only this | |
| if explicit_arg is not None: | |
| arg_count = match_argument(action, 'A') | |
| # if the action is a single-dash option and takes no | |
| # arguments, try to parse more single-dash options out | |
| # of the tail of the option string | |
| chars = self.prefix_chars | |
| if arg_count == 0 and option_string[1] not in chars: | |
| action_tuples.append((action, [], option_string)) | |
| for char in self.prefix_chars: | |
| option_string = char + explicit_arg[0] | |
| explicit_arg = explicit_arg[1:] or None | |
| optionals_map = self._option_string_actions | |
| if option_string in optionals_map: | |
| action = optionals_map[option_string] | |
| break | |
| else: | |
| msg = _('ignored explicit argument %r') | |
| raise ArgumentError(action, msg % explicit_arg) | |
| # if the action expect exactly one argument, we've | |
| # successfully matched the option; exit the loop | |
| elif arg_count == 1: | |
| stop = start_index + 1 | |
| args = [explicit_arg] | |
| action_tuples.append((action, args, option_string)) | |
| break | |
| # error if a double-dash option did not use the | |
| # explicit argument | |
| else: | |
| msg = _('ignored explicit argument %r') | |
| raise ArgumentError(action, msg % explicit_arg) | |
| # if there is no explicit argument, try to match the | |
| # optional's string arguments with the following strings | |
| # if successful, exit the loop | |
| 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] | |
| action_tuples.append((action, args, option_string)) | |
| break | |
| # add the Optional to the list and return the index at which | |
| # the Optional's string args stopped | |
| assert action_tuples | |
| for action, args, option_string in action_tuples: | |
| take_action(action, args, option_string) | |
| return stop | |
| # the list of Positionals left to be parsed; this is modified | |
| # by consume_positionals() | |
| positionals = self._get_positional_actions() | |
| # 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 | |
| extras = [] | |
| 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 extra arguments | |
| if start_index not in option_string_indices: | |
| strings = arg_strings[start_index:next_option_string_index] | |
| extras.extend(strings) | |
| start_index = next_option_string_index | |
| # 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 extras | |
| extras.extend(arg_strings[stop_index:]) | |
| # if we didn't use all the Positional objects, there were too few | |
| # arg strings supplied. | |
| if positionals: | |
| self.error(_('too few arguments')) | |
| # make sure all required actions were present | |
| for action in self._actions: | |
| if action.required: | |
| if action not in seen_actions: | |
| name = _get_action_name(action) | |
| self.error(_('argument %s is required') % name) | |
| # make sure all required groups had one option present | |
| for group in self._mutually_exclusive_groups: | |
| if group.required: | |
| for action in group._group_actions: | |
| if action in seen_non_default_actions: | |
| break | |
| # if no actions were used, report the error | |
| else: | |
| names = [_get_action_name(action) | |
| for action in group._group_actions | |
| if action.help is not SUPPRESS] | |
| msg = _('one of the arguments %s is required') | |
| self.error(msg % ' '.join(names)) | |
| # return the updated namespace and the extra arguments | |
| return namespace, extras | |
| def _read_args_from_files(self, arg_strings): | |
| # expand arguments referencing files | |
| new_arg_strings = [] | |
| for arg_string in arg_strings: | |
| # for regular arguments, just add them back into the list | |
| if arg_string[0] not in self.fromfile_prefix_chars: | |
| new_arg_strings.append(arg_string) | |
| # replace arguments referencing files with the file content | |
| else: | |
| try: | |
| args_file = open(arg_string[1:]) | |
| try: | |
| arg_strings = [] | |
| for arg_line in args_file.read().splitlines(): | |
| for arg in self.convert_arg_line_to_args(arg_line): | |
| arg_strings.append(arg) | |
| arg_strings = self._read_args_from_files(arg_strings) | |
| new_arg_strings.extend(arg_strings) | |
| finally: | |
| args_file.close() | |
| except IOError: | |
| err = _sys.exc_info()[1] | |
| self.error(str(err)) | |
| # return the modified argument list | |
| return new_arg_strings | |
| def convert_arg_line_to_args(self, arg_line): | |
| return [arg_line] | |
| 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 range(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, arg_string): | |
| # if it's an empty string, it was meant to be a positional | |
| if not arg_string: | |
| return None | |
| # if it doesn't start with a prefix, it was meant to be positional | |
| if not arg_string[0] in self.prefix_chars: | |
| return None | |
| # if the option string is present in the parser, return the action | |
| if arg_string in self._option_string_actions: | |
| action = self._option_string_actions[arg_string] | |
| return action, arg_string, None | |
| # if it's just a single character, it was meant to be positional | |
| if len(arg_string) == 1: | |
| return None | |
| # if the option string before the "=" is present, return the action | |
| if '=' in arg_string: | |
| option_string, explicit_arg = arg_string.split('=', 1) | |
| if option_string in self._option_string_actions: | |
| action = self._option_string_actions[option_string] | |
| return action, option_string, explicit_arg | |
| # search through all possible prefixes of the option string | |
| # and all actions in the parser for possible interpretations | |
| option_tuples = self._get_option_tuples(arg_string) | |
| # if multiple actions match, the option string was ambiguous | |
| if len(option_tuples) > 1: | |
| options = ', '.join([option_string | |
| for action, option_string, explicit_arg in option_tuples]) | |
| tup = arg_string, options | |
| self.error(_('ambiguous option: %s could match %s') % tup) | |
| # if exactly one action matched, this segmentation is good, | |
| # so return the parsed action | |
| elif len(option_tuples) == 1: | |
| option_tuple, = option_tuples | |
| return option_tuple | |
| # if it was not found as an option, but it looks like a negative | |
| # number, it was meant to be positional | |
| # unless there are negative-number-like options | |
| if self._negative_number_matcher.match(arg_string): | |
| if not self._has_negative_number_optionals: | |
| return None | |
| # if it contains a space, it was meant to be a positional | |
| if ' ' in arg_string: | |
| return None | |
| # it was meant to be an optional but there is no such option | |
| # in this parser (though it might be a valid option in a subparser) | |
| return None, arg_string, None | |
| def _get_option_tuples(self, option_string): | |
| result = [] | |
| # option strings starting with two prefix characters are only | |
| # split at the '=' | |
| chars = self.prefix_chars | |
| if option_string[0] in chars and option_string[1] in chars: | |
| if '=' in option_string: | |
| option_prefix, explicit_arg = option_string.split('=', 1) | |
| else: | |
| option_prefix = option_string | |
| explicit_arg = None | |
| for option_string in self._option_string_actions: | |
| if option_string.startswith(option_prefix): | |
| action = self._option_string_actions[option_string] | |
| tup = action, option_string, explicit_arg | |
| result.append(tup) | |
| # single character options can be concatenated with their arguments | |
| # but multiple character options always have to have their argument | |
| # separate | |
| elif option_string[0] in chars and option_string[1] not in chars: | |
| option_prefix = option_string | |
| explicit_arg = None | |
| short_option_prefix = option_string[:2] | |
| short_explicit_arg = option_string[2:] | |
| for option_string in self._option_string_actions: | |
| if option_string == short_option_prefix: | |
| action = self._option_string_actions[option_string] | |
| tup = action, option_string, short_explicit_arg | |
| result.append(tup) | |
| elif option_string.startswith(option_prefix): | |
| action = self._option_string_actions[option_string] | |
| tup = action, option_string, explicit_arg | |
| result.append(tup) | |
| # shouldn't ever get here | |
| else: | |
| self.error(_('unexpected option string: %s') % option_string) | |
| # return the collected option tuples | |
| return result | |
| 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 any number of options or arguments | |
| elif nargs == REMAINDER: | |
| nargs_pattern = '([-AO]*)' | |
| # allow one argument followed by any number of options or arguments | |
| elif nargs == 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 not in [PARSER, REMAINDER]: | |
| 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) | |
| # REMAINDER arguments convert all values, checking none | |
| elif action.nargs == REMAINDER: | |
| value = [self._get_value(action, v) for v in arg_strings] | |
| # PARSER arguments convert all values, but check only the first | |
| elif action.nargs == PARSER: | |
| value = [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 = [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) | |
| # ArgumentTypeErrors indicate errors | |
| except ArgumentTypeError: | |
| name = getattr(action.type, '__name__', repr(action.type)) | |
| msg = str(_sys.exc_info()[1]) | |
| raise ArgumentError(action, msg) | |
| # TypeErrors or ValueErrors also 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._actions, | |
| self._mutually_exclusive_groups) | |
| return formatter.format_help() | |
| def format_help(self): | |
| formatter = self._get_formatter() | |
| # usage | |
| formatter.add_usage(self.usage, self._actions, | |
| self._mutually_exclusive_groups) | |
| # description | |
| formatter.add_text(self.description) | |
| # positionals, optionals and user-defined groups | |
| for action_group in self._action_groups: | |
| formatter.start_section(action_group.title) | |
| formatter.add_text(action_group.description) | |
| formatter.add_arguments(action_group._group_actions) | |
| formatter.end_section() | |
| # epilog | |
| formatter.add_text(self.epilog) | |
| # determine help from format above | |
| return formatter.format_help() | |
| def format_version(self): | |
| import warnings | |
| warnings.warn( | |
| 'The format_version method is deprecated -- the "version" ' | |
| 'argument to ArgumentParser is no longer supported.', | |
| DeprecationWarning) | |
| 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): | |
| if file is None: | |
| file = _sys.stdout | |
| self._print_message(self.format_usage(), file) | |
| def print_help(self, file=None): | |
| if file is None: | |
| file = _sys.stdout | |
| self._print_message(self.format_help(), file) | |
| def print_version(self, file=None): | |
| import warnings | |
| warnings.warn( | |
| 'The print_version method is deprecated -- the "version" ' | |
| 'argument to ArgumentParser is no longer supported.', | |
| DeprecationWarning) | |
| 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: | |
| self._print_message(message, _sys.stderr) | |
| _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)) |