/usr/lib/python2.7/dist-packages/IPython/core/magic_arguments.py is in python-ipython 5.1.0-3.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 | ''' A decorator-based method of constructing IPython magics with `argparse`
option handling.
New magic functions can be defined like so::
from IPython.core.magic_arguments import (argument, magic_arguments,
parse_argstring)
@magic_arguments()
@argument('-o', '--option', help='An optional argument.')
@argument('arg', type=int, help='An integer positional argument.')
def magic_cool(self, arg):
""" A really cool magic command.
"""
args = parse_argstring(magic_cool, arg)
...
The `@magic_arguments` decorator marks the function as having argparse arguments.
The `@argument` decorator adds an argument using the same syntax as argparse's
`add_argument()` method. More sophisticated uses may also require the
`@argument_group` or `@kwds` decorator to customize the formatting and the
parsing.
Help text for the magic is automatically generated from the docstring and the
arguments::
In[1]: %cool?
%cool [-o OPTION] arg
A really cool magic command.
positional arguments:
arg An integer positional argument.
optional arguments:
-o OPTION, --option OPTION
An optional argument.
Inheritance diagram:
.. inheritance-diagram:: IPython.core.magic_arguments
:parts: 3
'''
#-----------------------------------------------------------------------------
# Copyright (C) 2010-2011, IPython Development Team.
#
# Distributed under the terms of the Modified BSD License.
#
# The full license is in the file COPYING.txt, distributed with this software.
#-----------------------------------------------------------------------------
import argparse
import re
# Our own imports
from IPython.core.error import UsageError
from IPython.utils.decorators import undoc
from IPython.utils.process import arg_split
from IPython.utils.text import dedent
NAME_RE = re.compile(r"[a-zA-Z][a-zA-Z0-9_-]*$")
@undoc
class MagicHelpFormatter(argparse.RawDescriptionHelpFormatter):
"""A HelpFormatter with a couple of changes to meet our needs.
"""
# Modified to dedent text.
def _fill_text(self, text, width, indent):
return argparse.RawDescriptionHelpFormatter._fill_text(self, dedent(text), width, indent)
# Modified to wrap argument placeholders in <> where necessary.
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)
# IPYTHON MODIFICATION: If args_string is not a plain name, wrap
# it in <> so it's valid RST.
if not NAME_RE.match(args_string):
args_string = "<%s>" % args_string
for option_string in action.option_strings:
parts.append('%s %s' % (option_string, args_string))
return ', '.join(parts)
# Override the default prefix ('usage') to our % magic escape,
# in a code block.
def add_usage(self, usage, actions, groups, prefix="::\n\n %"):
super(MagicHelpFormatter, self).add_usage(usage, actions, groups, prefix)
class MagicArgumentParser(argparse.ArgumentParser):
""" An ArgumentParser tweaked for use by IPython magics.
"""
def __init__(self,
prog=None,
usage=None,
description=None,
epilog=None,
parents=None,
formatter_class=MagicHelpFormatter,
prefix_chars='-',
argument_default=None,
conflict_handler='error',
add_help=False):
if parents is None:
parents = []
super(MagicArgumentParser, self).__init__(prog=prog, usage=usage,
description=description, epilog=epilog,
parents=parents, formatter_class=formatter_class,
prefix_chars=prefix_chars, argument_default=argument_default,
conflict_handler=conflict_handler, add_help=add_help)
def error(self, message):
""" Raise a catchable error instead of exiting.
"""
raise UsageError(message)
def parse_argstring(self, argstring):
""" Split a string into an argument list and parse that argument list.
"""
argv = arg_split(argstring)
return self.parse_args(argv)
def construct_parser(magic_func):
""" Construct an argument parser using the function decorations.
"""
kwds = getattr(magic_func, 'argcmd_kwds', {})
if 'description' not in kwds:
kwds['description'] = getattr(magic_func, '__doc__', None)
arg_name = real_name(magic_func)
parser = MagicArgumentParser(arg_name, **kwds)
# Reverse the list of decorators in order to apply them in the
# order in which they appear in the source.
group = None
for deco in magic_func.decorators[::-1]:
result = deco.add_to_parser(parser, group)
if result is not None:
group = result
# Replace the magic function's docstring with the full help text.
magic_func.__doc__ = parser.format_help()
return parser
def parse_argstring(magic_func, argstring):
""" Parse the string of arguments for the given magic function.
"""
return magic_func.parser.parse_argstring(argstring)
def real_name(magic_func):
""" Find the real name of the magic.
"""
magic_name = magic_func.__name__
if magic_name.startswith('magic_'):
magic_name = magic_name[len('magic_'):]
return getattr(magic_func, 'argcmd_name', magic_name)
class ArgDecorator(object):
""" Base class for decorators to add ArgumentParser information to a method.
"""
def __call__(self, func):
if not getattr(func, 'has_arguments', False):
func.has_arguments = True
func.decorators = []
func.decorators.append(self)
return func
def add_to_parser(self, parser, group):
""" Add this object's information to the parser, if necessary.
"""
pass
class magic_arguments(ArgDecorator):
""" Mark the magic as having argparse arguments and possibly adjust the
name.
"""
def __init__(self, name=None):
self.name = name
def __call__(self, func):
if not getattr(func, 'has_arguments', False):
func.has_arguments = True
func.decorators = []
if self.name is not None:
func.argcmd_name = self.name
# This should be the first decorator in the list of decorators, thus the
# last to execute. Build the parser.
func.parser = construct_parser(func)
return func
class ArgMethodWrapper(ArgDecorator):
"""
Base class to define a wrapper for ArgumentParser method.
Child class must define either `_method_name` or `add_to_parser`.
"""
_method_name = None
def __init__(self, *args, **kwds):
self.args = args
self.kwds = kwds
def add_to_parser(self, parser, group):
""" Add this object's information to the parser.
"""
if group is not None:
parser = group
getattr(parser, self._method_name)(*self.args, **self.kwds)
return None
class argument(ArgMethodWrapper):
""" Store arguments and keywords to pass to add_argument().
Instances also serve to decorate command methods.
"""
_method_name = 'add_argument'
class defaults(ArgMethodWrapper):
""" Store arguments and keywords to pass to set_defaults().
Instances also serve to decorate command methods.
"""
_method_name = 'set_defaults'
class argument_group(ArgMethodWrapper):
""" Store arguments and keywords to pass to add_argument_group().
Instances also serve to decorate command methods.
"""
def add_to_parser(self, parser, group):
""" Add this object's information to the parser.
"""
return parser.add_argument_group(*self.args, **self.kwds)
class kwds(ArgDecorator):
""" Provide other keywords to the sub-parser constructor.
"""
def __init__(self, **kwds):
self.kwds = kwds
def __call__(self, func):
func = super(kwds, self).__call__(func)
func.argcmd_kwds = self.kwds
return func
__all__ = ['magic_arguments', 'argument', 'argument_group', 'kwds',
'parse_argstring']
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