Source code for jsonargparse.formatters

"""Formatter classes."""

import re
from argparse import Action, _HelpAction, HelpFormatter, OPTIONAL, SUPPRESS, ZERO_OR_MORE
from contextlib import contextmanager
from contextvars import ContextVar
from io import StringIO
from string import Template
from typing import Optional, Union

from .actions import (
    ActionConfigFile,
    ActionYesNo,
    _ActionConfigLoad,
    _ActionSubCommands,
    _find_action,
    filter_default_actions,
)
from .link_arguments import ActionLink
from .namespace import Namespace
from .optionals import import_ruyaml
from .type_checking import ArgumentParser, ruyamlCommentedMap
from .typehints import ActionTypeHint, type_to_str


__all__ = ['DefaultHelpFormatter']


empty_help: str = '_EMPTY_HELP_'


formatter_parser: ContextVar = ContextVar('formatter_parser')
formatter_defaults: ContextVar = ContextVar('formatter_defaults')


@contextmanager
def formatter_context(parser: 'ArgumentParser', defaults: Optional[Namespace] = None):
    prev_parser = formatter_parser.set(parser)
    prev_defaults = formatter_defaults.set(defaults)
    try:
        yield
    finally:
        formatter_parser.reset(prev_parser)
        formatter_defaults.reset(prev_defaults)


class PercentTemplate(Template):
    delimiter = '%'
    pattern = r'''
    \%\((?:
    (?P<escaped>\%\%)|
    (?P<named>[_a-z][_a-z0-9]*)\)s|
    (?P<braced>[_a-z][_a-z0-9]*)\)s|
    (?P<invalid>)
    )
    '''  # type: ignore


[docs]class DefaultHelpFormatter(HelpFormatter): """Help message formatter that includes types, default values and env var names. This class is an extension of `argparse.HelpFormatter <https://docs.python.org/3/library/argparse.html#argparse.HelpFormatter>`_. Default values are always included. Furthermore, if the parser is configured with :code:`default_env=True` command line options are preceded by 'ARG:' and the respective environment variable name is included preceded by 'ENV:'. """ def _get_help_string(self, action): action_help = ' ' if action.help == empty_help else action.help if isinstance(action, ActionConfigFile): return action_help if isinstance(action, _HelpAction): help_str = action_help[0].upper() + action_help[1:] if help_str[-1] != '.': help_str += '.' return help_str help_str = '' is_required = hasattr(action, '_required') and action._required if is_required: help_str = 'required' if '%(type)' not in action_help and self._get_type_str(action) is not None: help_str += (', ' if help_str else '') + 'type: %(type)s' if '%(default)' not in action_help and \ action.default != SUPPRESS and \ (action.default is not None or not is_required) and \ (action.option_strings or action.nargs in {OPTIONAL, ZERO_OR_MORE}): help_str += (', ' if help_str else '') + 'default: %(default)s' if isinstance(action, ActionTypeHint): help_str += action.extra_help() return action_help + (' ('+help_str+')' if help_str else '') def _format_usage(self, *args, **kwargs): usage = super()._format_usage(*args, **kwargs) parser = formatter_parser.get() for key in parser.required_args: try: default = parser.get_default(key) except KeyError: default = None if default is None and f'[--{key} ' in usage: usage = re.sub(f'\\[(--{key} [^\\]]+)]', r'\1', usage, count=1) return usage def _format_action_invocation(self, action): parser = formatter_parser.get() if action.option_strings == [] or action.default == SUPPRESS or not parser.default_env: return super()._format_action_invocation(action) extr = '' if parser.default_env: extr += '\n ENV: ' + get_env_var(self, action) return 'ARG: ' + super()._format_action_invocation(action) + extr def _get_default_metavar_for_optional(self, action): return action.dest.rsplit('.')[-1].upper() def _expand_help(self, action): params = dict(vars(action), prog=self._prog) if params.get('choices') is not None: choices_str = ', '.join([str(c) for c in params['choices']]) params['choices'] = choices_str type_str = self._get_type_str(action) if type_str is not None: params['type'] = type_str orig_default = action.default if params.get('default') == SUPPRESS: del params['default'] elif 'default' in params: defaults = formatter_defaults.get() if defaults is not None: params['default'] = action.default = defaults.get(action.dest) if params['default'] is None: params['default'] = 'null' elif isinstance(params['default'], Namespace): params['default'] = params['default'].as_dict() help_str = PercentTemplate(self._get_help_string(action)).safe_substitute(params) action.default = orig_default return help_str def _get_type_str(self, action): type_str = None if isinstance(action, ActionYesNo): type_str = 'bool' elif action.type is not None: type_str = type_to_str(action.type) elif isinstance(action, ActionTypeHint): type_str = type_to_str(action._typehint) return type_str def add_usage(self, usage, actions, groups, prefix=None): actions = [a for a in actions if not isinstance(a, ActionLink)] super().add_usage(usage, actions, groups, prefix=prefix)
[docs] def add_yaml_comments(self, cfg: str) -> str: """Adds help text as yaml comments.""" ruyaml = import_ruyaml('add_yaml_comments') yaml = ruyaml.YAML() cfg = yaml.load(cfg) def get_subparsers(parser, prefix=''): subparsers = {} if parser._subparsers is not None: for key, subparser in parser._subparsers._group_actions[0].choices.items(): full_key = (prefix+'.' if prefix else '')+key subparsers[full_key] = subparser subparsers.update(get_subparsers(subparser, prefix=full_key)) return subparsers parser = formatter_parser.get() parsers = get_subparsers(parser) parsers[None] = parser group_titles = {} for parser_key, parser in parsers.items(): prefix = '' if parser_key is None else parser_key + '.' for group in parser._action_groups: actions = filter_default_actions(group._group_actions) actions = [a for a in actions if not isinstance(a, (_ActionConfigLoad, ActionConfigFile, _ActionSubCommands))] keys = {re.sub(r'\.?[^.]+$', '', a.dest) for a in actions} for key in keys: full_key = prefix + key if key != '' else parser_key group_titles[full_key] = group.title def set_comments(cfg, prefix='', depth=0): for key in cfg.keys(): full_key = (prefix+'.' if prefix else '')+key action = _find_action(parser, full_key) text = None if full_key in group_titles and isinstance(cfg[key], dict): text = group_titles[full_key] elif action is not None and action.help not in {None, SUPPRESS}: text = self._expand_help(action) if isinstance(cfg[key], dict): if text: self.set_yaml_group_comment(text, cfg, key, depth) set_comments(cfg[key], full_key, depth+1) elif text: self.set_yaml_argument_comment(text, cfg, key, depth) if parser.description is not None: self.set_yaml_start_comment(parser.description, cfg) set_comments(cfg) out = StringIO() yaml.dump(cfg, out) return out.getvalue()
[docs] def set_yaml_start_comment( self, text: str, cfg: 'ruyamlCommentedMap', ): """Sets the start comment to a ruyaml object. Args: text: The content to use for the comment. cfg: The ruyaml object. """ cfg.yaml_set_start_comment(text)
[docs] def set_yaml_group_comment( self, text: str, cfg: 'ruyamlCommentedMap', key: str, depth: int, ): """Sets the comment for a group to a ruyaml object. Args: text: The content to use for the comment. cfg: The parent ruyaml object. key: The key of the group. depth: The nested level of the group. """ cfg.yaml_set_comment_before_after_key(key, before='\n'+text, indent=2*depth)
[docs] def set_yaml_argument_comment( self, text: str, cfg: 'ruyamlCommentedMap', key: str, depth: int, ): """Sets the comment for an argument to a ruyaml object. Args: text: The content to use for the comment. cfg: The parent ruyaml object. key: The key of the argument. depth: The nested level of the argument. """ cfg.yaml_set_comment_before_after_key(key, before='\n'+text, indent=2*depth)
def get_env_var(parser_or_formatter: Union['ArgumentParser', DefaultHelpFormatter], action: Action) -> str: """Returns the environment variable for a given parser or formatter and action.""" if isinstance(parser_or_formatter, DefaultHelpFormatter): parser = formatter_parser.get() else: parser = parser_or_formatter env_var = (parser.env_prefix+'_' if parser.env_prefix else '') + action.dest env_var = env_var.replace('.', '__').upper() return env_var