zephyr/scripts/meta/west/cmd/__init__.py

75 lines
2.3 KiB
Python

# Copyright 2018 Open Source Foundries Limited.
#
# SPDX-License-Identifier: Apache-2.0
'''West's commands subpackage.
All commands should be implemented within modules in this package.
'''
from abc import ABC, abstractmethod
__all__ = ['CommandContextError', 'WestCommand']
class CommandContextError(RuntimeError):
'''Indicates that a context-dependent command could not be run.'''
class WestCommand(ABC):
'''Abstract superclass for a west command.
All top-level commands supported by west implement this interface.'''
def __init__(self, name, description, accepts_unknown_args=False):
'''Create a command instance.
`name`: the command's name, as entered by the user.
`description`: one-line command description to show to the user.
`accepts_unknown_args`: if true, the command can handle
arbitrary unknown command line arguments in its run()
method. Otherwise, passing unknown arguments will cause
UnknownArgumentsError to be raised.
'''
self.name = name
self.description = description
self._accept_unknown = accepts_unknown_args
def run(self, args, unknown):
'''Run the command.
`args`: known arguments parsed via `register_arguments()`
`unknown`: unknown arguments present on the command line
'''
if unknown and not self._accept_unknown:
self.parser.error('unexpected arguments: {}'.format(unknown))
self.do_run(args, unknown)
def add_parser(self, parser_adder):
'''Registers a parser for this command, and returns it.
'''
self.parser = self.do_add_parser(parser_adder)
return self.parser
#
# Mandatory subclass hooks
#
@abstractmethod
def do_add_parser(self, parser_adder):
'''Subclass method for registering command line arguments.
`parser_adder` is an argparse argument subparsers adder.'''
@abstractmethod
def do_run(self, args, unknown):
'''Subclasses must implement; called when the command is run.
`args` is the namespace of parsed known arguments.
If `accepts_unknown_args` was False when constructing this
object, `unknown` will be empty. Otherwise, it is an iterable
containing all unknown arguments present on the command line.
'''