Python argparse.Action() Examples

def cli_skip_missing_interpreter(parser):
    class SkipMissingInterpreterAction(argparse.Action):
        def __call__(self, parser, namespace, values, option_string=None):
            value = "true" if values is None else values
            if value not in ("config", "true", "false"):
                raise argparse.ArgumentTypeError("value must be config, true or false")
            setattr(namespace, self.dest, value)

    parser.add_argument(
        "-s",
        "--skip-missing-interpreters",
        default="config",
        metavar="val",
        nargs="?",
        action=SkipMissingInterpreterAction,
        help="don't fail tests for missing interpreters: {config,true,false} choice",
    ) 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def make_datalab_help_action(self):
    """Custom action for --datalab-help.

    The action output the package specific parameters and will be part of "%%ml train"
    help string.
    """
    datalab_help = self.datalab_help
    epilog = self.datalab_epilog

    class _CustomAction(argparse.Action):

      def __init__(self, option_strings, dest, help=None):
        super(_CustomAction, self).__init__(
            option_strings=option_strings, dest=dest, nargs=0, help=help)

      def __call__(self, parser, args, values, option_string=None):
        print('\n\n'.join(datalab_help))
        if epilog:
          print(epilog)

        # We have printed all help string datalab needs. If we don't quit, it will complain about
        # missing required arguments later.
        quit()
    return _CustomAction 

def make_datalab_help_action(self):
    """Custom action for --datalab-help.

    The action output the package specific parameters and will be part of "%%ml train"
    help string.
    """
    datalab_help = self.datalab_help
    epilog = self.datalab_epilog

    class _CustomAction(argparse.Action):

      def __init__(self, option_strings, dest, help=None):
        super(_CustomAction, self).__init__(
            option_strings=option_strings, dest=dest, nargs=0, help=help)

      def __call__(self, parser, args, values, option_string=None):
        print('\n\n'.join(datalab_help))
        if epilog:
          print(epilog)

        # We have printed all help string datalab needs. If we don't quit, it will complain about
        # missing required arguments later.
        quit()
    return _CustomAction 

def get_argparse_extension_checker(choices, dir_allowed=False):
    """Get an :class:`argparge.Action` class that can check for correct extensions.

    Returns:
        argparse.Action: a class (not an instance) of an argparse action.
    """

    class Act(argparse.Action):
        def __call__(self, parser, namespace, fname, option_string=None):
            is_valid = any(map(lambda choice: fname[-len(choice):] == choice, choices))

            if not is_valid and dir_allowed and os.path.isdir(fname):
                is_valid = True

            if is_valid:
                setattr(namespace, self.dest, fname)
            else:
                option_string = '({})'.format(option_string) if option_string else ''
                parser.error("File doesn't end with one of {}{}".format(choices, option_string))

    return Act 

def add_version_alias(parser):
    """
    Add --version as a (hidden) alias for the version command.

    It's not uncommon to blindly run a command with --version as the sole
    argument, so its useful to make that Just Work.
    """

    class run_version_command(argparse.Action):
        def __call__(self, *args, **kwargs):
            opts = SimpleNamespace()
            sys.exit( version.run(opts) )

    return parser.add_argument(
        "--version",
        nargs  = 0,
        help   = argparse.SUPPRESS,
        action = run_version_command) 

def storeBool(boolDefault, ep):
    class _StoreBoolAction(argparse.Action):
        def __init__(self, option_strings, dest, help=None):
            super(_StoreBoolAction, self).__init__(
                option_strings=option_strings,
                dest=dest,
                nargs=0,
                const=boolDefault,
                default=False,
                required=False,
                help=help,
            )

        def __call__(self, parser, namespace, values, option_string=None):
            ep.cs[self.dest] = self.const
            ep.settingsProvidedOnCommandLine.append(self.dest)
            ep.cs.failOnLoad()

    return _StoreBoolAction 

def setSetting(ep):
    class _SetSettingAction(argparse.Action):
        """This class loads the command line supplied setting values into the
        :py:data:`armi.settings.cs`
        """

        def __call__(self, parser, namespace, values, option_string=None):
            ep.cs[self.dest] = values  # correctly converts type
            ep.settingsProvidedOnCommandLine.append(self.dest)
            ep.cs.failOnLoad()

    return _SetSettingAction


# Q: Why does this require special treatment? Why not treat it like the other
#    case settings and use setSetting action?
# A: Because caseTitle is no longer an actual cs setting. It's a instance attr. 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def test(self):

        def get_my_type(string):
            return 'my_type{%s}' % string

        parser = argparse.ArgumentParser()
        parser.register('type', 'my_type', get_my_type)
        parser.add_argument('-x', type='my_type')
        parser.add_argument('y', type='my_type')

        self.assertEqual(parser.parse_args('1'.split()),
                         NS(x=None, y='my_type{1}'))
        self.assertEqual(parser.parse_args('-x 1 42'.split()),
                         NS(x='my_type{1}', y='my_type{42}'))


# ============
# Action tests
# ============ 

def assembleConfigHelps(self, pdlist, type, main):
		class customArgsAction(argparse.Action):
			def __call__(self, parser, args, values, option_string=None):
				main.quietMode = True
				main.init_quietMode()
				main.prepareBuilding(64)
				main.build_mingw(64)
				main.initBuildFolders()
				for k, v in pdlist.items():
					if '_disabled' not in v:
						if '_info' in v:
							beforePath = os.getcwd()
							path = main.getPackagePath(k, v, type)
							main.cchdir(path)
							if os.path.isfile(os.path.join(path, "configure")):
								os.system("./configure --help")
							if os.path.isfile(os.path.join(path, "waf")):
								os.system("./waf --help")
							main.cchdir(beforePath)
							print("-------------------")
				setattr(args, self.dest, values)
				parser.exit()
		return customArgsAction 

def __call__(
        self,
        parser,  # type: argparse.ArgumentParser
        namespace,  # type: argparse.Namespace
        values,  # type: Union[ARGPARSE_TEXT, Sequence[Any], None]
        option_string=None,  # type: Optional[ARGPARSE_TEXT]
    ):
        # type: (...) -> None
        """Checks to make sure that the destination is empty before writing.

        :raises parser.error: if destination is already set
        """
        if getattr(namespace, self.dest) is not None:  # type: ignore # typeshed doesn't know about Action.dest yet?
            parser.error("{} argument may not be specified more than once".format(option_string))
            return
        setattr(namespace, self.dest, values)  # type: ignore # typeshed doesn't know about Action.dest yet? 

def choices_with_default(choices, default):
    """This closure defines an argparser custom action that ensures an argument
       value is in a list of choices, and if not, sets the argument to a default
       value.

       Implementing this argparser action instead of using only a 'choices' list
       for the argument works better for a script called from Jamf where an
       optional parameter may be omitted from the policy definition, but
       subsequent parameters are passed, ie. script.py 1 2 3 [omitted] 5 6
    """
    class customAction(argparse.Action):
        def __call__(self, parser, args, values, option_string=None):
            if (values in choices) or (values == default):
                setattr(args, self.dest, values)
            else:
                setattr(args, self.dest, default)

    return customAction 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def load_config(self):
        """Load the config file optionally given by --config argument

        Return the string read from sys.argv, with '--config
        <config-file>' removed

        """
        parser = argparse.ArgumentParser(add_help=False)

        class _ConfigAction(argparse.Action):
            def __call__(self, parser, namespace, value, option_string=None):
                if not os.path.isfile(value):
                    raise IOError(
                        'configuration file not found {}'.format(value))

                print('loading configuration from {}'.format(value))
                utils.config.read(value)

        # add a configuration argument
        parser.add_argument(
            '-c', '--config', metavar='<config-file>', action=_ConfigAction)

        return parser.parse_known_args()[1] 

def add_argument_os_code_name_and_arch_tuples(parser, required=True):
    class _AddUbuntuTupleAction(argparse.Action):

        def __call__(self, parser, args, values, option_string=None):
            import sys
            print('WARNING: ' + self.help, file=sys.stderr)
            for value in values:
                if value.count(':') != 1:
                    raise argparse.ArgumentError(
                        argument=self,
                        message='expected 2 parts separated by colons')
            setattr(
                args, 'os_name_and_os_code_name_and_arch_tuples',
                [('ubuntu:' + value).split(':') for value in values])
            setattr(args, self.dest, values)

    parser.add_argument(
        '--os-code-name-and-arch-tuples',
        nargs='+',
        required=required, action=_AddUbuntuTupleAction,
        help="DEPRECATED: Use '--os-name-and-os-code-name-and-arch-tuples'") 

def test(self):

        def get_my_type(string):
            return 'my_type{%s}' % string

        parser = argparse.ArgumentParser()
        parser.register('type', 'my_type', get_my_type)
        parser.add_argument('-x', type='my_type')
        parser.add_argument('y', type='my_type')

        self.assertEqual(parser.parse_args('1'.split()),
                         NS(x=None, y='my_type{1}'))
        self.assertEqual(parser.parse_args('-x 1 42'.split()),
                         NS(x='my_type{1}', y='my_type{42}'))


# ============
# Action tests
# ============ 

def get_constrained_float_action(
    min_val: Optional[float] = None, max_val: Optional[float] = None
) -> Type[argparse.Action]:
    class ConstrainedFloatAction(argparse.Action):
        """Custom action for ensuring floats arguments meet these."""

        def __call__(self, parser, namespace, values, option_string=None):  # type: ignore
            if min_val is not None and values < min_val:
                parser.error("{0} must be no smaller than {1}.".format(option_string, min_val))
            if max_val is not None and values > max_val:
                parser.error("{0} must be no greater than {1}.".format(option_string, max_val))

            setattr(namespace, self.dest, values)

    return ConstrainedFloatAction 

def _get_parent_class(self, **kwargs):
        # wrap any existing action
        action = kwargs.get('action', None)
        parent_class = argparse.Action

        # action is either a user-defined Action class or a string referring a library-defined Action
        if isinstance(action, type) and issubclass(action, argparse.Action):
            parent_class = action
        elif isinstance(action, str):
            parent_class = self.command_loader.cli_ctx.invocation.parser._registries['action'][action]  # pylint: disable=protected-access
        return parent_class 

def setUp(self):
        from knack.help_files import helps

        class LoggerAction(argparse.Action):

            def __call__(self, parser, namespace, values, option_string=None):
                print("Side-effect from some original action!", file=sys.stderr)

        class ExperimentalTestCommandLoader(CLICommandsLoader):
            def load_command_table(self, args):
                super(ExperimentalTestCommandLoader, self).load_command_table(args)
                with CommandGroup(self, '', '{}#{{}}'.format(__name__)) as g:
                    g.command('arg-test', 'example_arg_handler')
                return self.command_table

            def load_arguments(self, command):
                with ArgumentsContext(self, 'arg-test') as c:
                    c.argument('arg1', help='Arg1', is_experimental=True, action=LoggerAction)

                super(ExperimentalTestCommandLoader, self).load_arguments(command)

        helps['grp1'] = """
    type: group
    short-summary: A group.
"""
        self.cli_ctx = DummyCLI(commands_loader_cls=ExperimentalTestCommandLoader) 

def setUp(self):
        from knack.help_files import helps

        class LoggerAction(argparse.Action):

            def __call__(self, parser, namespace, values, option_string=None):
                print("Side-effect from some original action!", file=sys.stderr)

        class PreviewTestCommandLoader(CLICommandsLoader):
            def load_command_table(self, args):
                super(PreviewTestCommandLoader, self).load_command_table(args)
                with CommandGroup(self, '', '{}#{{}}'.format(__name__)) as g:
                    g.command('arg-test', 'example_arg_handler')
                return self.command_table

            def load_arguments(self, command):
                with ArgumentsContext(self, 'arg-test') as c:
                    c.argument('arg1', help='Arg1', is_preview=True, action=LoggerAction)

                super(PreviewTestCommandLoader, self).load_arguments(command)

        helps['grp1'] = """
    type: group
    short-summary: A group.
"""
        self.cli_ctx = DummyCLI(commands_loader_cls=PreviewTestCommandLoader) 

def check(validator):
    class CustomAction(argparse.Action):
        def __call__(self, parser, namespace, values, option_string=None):
            validator(values)
            setattr(namespace, self.dest, values)

    return CustomAction 

def check_size(min_size=None, max_size=None):
    class CustomAction(argparse.Action):
        def __call__(self, parser, namespace, values, option_string=None):
            validate((values, self.type, min_size, max_size, self.dest))
            setattr(namespace, self.dest, values)

    return CustomAction 

def arg_deprecated_action(new_arg):  # pragma: no cover
    class ArgDeprecated(argparse.Action):
        def __call__(self, parser, namespace, values, option_string=None):
            logger.warning('Argument %s deprecated. Use %s instead',
                           '|'.join(self.option_strings), new_arg)
            setattr(namespace, self.dest, values)
    return ArgDeprecated 

def pytest_addoption(parser):
    class IntList(argparse.Action):
        def __call__(self, parser, namespace, values, option_string=None):
            setattr(namespace, self.dest, tuple(int(value) for value in values.split(',')))
    parser.addoption('--piece-sizes', default=(8,), action=IntList,
                     help='Comma-separated list of piece sizes to use for test torrents')
    parser.addoption('--piece-counts', default=(1, 2, 3, 4, 6, 9), action=IntList,
                     help='Comma-separated list of number of pieces to use for test torrents')
    parser.addoption('--file-counts', default=(1, 2, 3, 4), action=IntList,
                     help='Comma-separated list of number of files to use for test torrents')
    parser.addoption('--fuzzy', action='store_true',
                     help='Whether to randomize file sizes for --file-counts >= 4') 

def test(self):

        def get_my_type(string):
            return 'my_type{%s}' % string

        parser = argparse.ArgumentParser()
        parser.register('type', 'my_type', get_my_type)
        parser.add_argument('-x', type='my_type')
        parser.add_argument('y', type='my_type')

        self.assertEqual(parser.parse_args('1'.split()),
                         NS(x=None, y='my_type{1}'))
        self.assertEqual(parser.parse_args('-x 1 42'.split()),
                         NS(x='my_type{1}', y='my_type{42}'))


# ============
# Action tests
# ============ 

def test_user_defined_action(self):

        class Success(Exception):
            pass

        class Action(object):

            def __init__(self,
                         option_strings,
                         dest,
                         const,
                         default,
                         required=False):
                if dest == 'spam':
                    if const is Success:
                        if default is Success:
                            raise Success()

            def __call__(self, *args, **kwargs):
                pass

        parser = argparse.ArgumentParser()
        self.assertRaises(Success, parser.add_argument, '--spam',
                          action=Action, default=Success, const=Success)
        self.assertRaises(Success, parser.add_argument, 'spam',
                          action=Action, default=Success, const=Success)

# ================================
# Actions returned by add_argument
# ================================ 

def test_optional(self):
        option = argparse.Action(
            option_strings=['--foo', '-a', '-b'],
            dest='b',
            type='int',
            nargs='+',
            default=42,
            choices=[1, 2, 3],
            help='HELP',
            metavar='METAVAR')
        string = (
            "Action(option_strings=['--foo', '-a', '-b'], dest='b', "
            "nargs='+', const=None, default=42, type='int', "
            "choices=[1, 2, 3], help='HELP', metavar='METAVAR')")
        self.assertStringEqual(option, string) 

def test_argument(self):
        argument = argparse.Action(
            option_strings=[],
            dest='x',
            type=float,
            nargs='?',
            default=2.5,
            choices=[0.5, 1.5, 2.5],
            help='H HH H',
            metavar='MV MV MV')
        string = (
            "Action(option_strings=[], dest='x', nargs='?', "
            "const=None, default=2.5, type=%r, choices=[0.5, 1.5, 2.5], "
            "help='H HH H', metavar='MV MV MV')" % float)
        self.assertStringEqual(argument, string)