# coding=utf-8 """Variant on standard library's cmd with extra features. To use, simply import cmd2.Cmd instead of cmd.Cmd; use precisely as though you were using the standard library's cmd, while enjoying the extra features. Searchable command history (commands: "history") Run commands from file, save to file, edit commands in file Multi-line commands Special-character shortcut commands (beyond cmd's "?" and "!") Settable environment parameters Parsing commands with `argparse` argument parsers (flags) Redirection to file or paste buffer (clipboard) with > or >> Easy transcript-based testing of applications (see examples/example.py) Bash-style ``select`` available Note that redirection with > and | will only work if `self.poutput()` is used in place of `print`. - Catherine Devlin, Jan 03 2008 - catherinedevlin.blogspot.com Git repository on GitHub at https://github.com/python-cmd2/cmd2 """ # This module has many imports, quite a few of which are only # infrequently utilized. To reduce the initial overhead of # import this module, many of these imports are lazy-loaded # i.e. we only import the module when we use it # For example, we don't import the 'traceback' module # until the pexcept() function is called and the debug # setting is True import argparse import cmd import copy import functools import glob import inspect import os import pydoc import re import sys import tempfile import threading from code import ( InteractiveConsole, ) from collections import ( OrderedDict, namedtuple, ) from contextlib import ( redirect_stdout, ) from types import ( FrameType, ModuleType, ) from typing import ( IO, TYPE_CHECKING, Any, Callable, Dict, Iterable, List, Mapping, Optional, Set, TextIO, Tuple, Type, TypeVar, Union, cast, ) from . import ( ansi, argparse_completer, argparse_custom, constants, plugin, utils, ) from .argparse_custom import ( ChoicesProviderFunc, CompleterFunc, CompletionItem, ) from .clipboard import ( get_paste_buffer, write_to_paste_buffer, ) from .command_definition import ( CommandFunc, CommandSet, ) from .constants import ( CLASS_ATTR_DEFAULT_HELP_CATEGORY, COMMAND_FUNC_PREFIX, COMPLETER_FUNC_PREFIX, HELP_FUNC_PREFIX, ) from .decorators import ( CommandParent, as_subcommand_to, with_argparser, ) from .exceptions import ( Cmd2ShlexError, CommandSetRegistrationError, CompletionError, EmbeddedConsoleExit, EmptyStatement, PassThroughException, RedirectionError, SkipPostcommandHooks, ) from .history import ( History, HistoryItem, single_line_format, ) from .parsing import ( Macro, MacroArg, Statement, StatementParser, shlex_split, ) # NOTE: When using gnureadline with Python 3.13, start_ipython needs to be imported before any readline-related stuff try: from IPython import start_ipython # type: ignore[import] except ImportError: pass from .rl_utils import ( RlType, rl_escape_prompt, rl_get_display_prompt, rl_get_point, rl_get_prompt, rl_in_search_mode, rl_set_prompt, rl_type, rl_warning, vt100_support, ) from .table_creator import ( Column, SimpleTable, ) from .utils import ( Settable, get_defining_class, strip_doc_annotations, suggest_similar, ) # Set up readline if rl_type == RlType.NONE: # pragma: no cover sys.stderr.write(ansi.style_warning(rl_warning)) else: from .rl_utils import ( # type: ignore[attr-defined] readline, rl_force_redisplay, ) # Used by rlcompleter in Python console loaded by py command orig_rl_delims = readline.get_completer_delims() if rl_type == RlType.PYREADLINE: # Save the original pyreadline3 display completion function since we need to override it and restore it orig_pyreadline_display = readline.rl.mode._display_completions elif rl_type == RlType.GNU: # Get the readline lib so we can make changes to it import ctypes from .rl_utils import ( readline_lib, ) rl_basic_quote_characters = ctypes.c_char_p.in_dll(readline_lib, "rl_basic_quote_characters") orig_rl_basic_quotes = cast(bytes, ctypes.cast(rl_basic_quote_characters, ctypes.c_void_p).value) class _SavedReadlineSettings: """readline settings that are backed up when switching between readline environments""" def __init__(self) -> None: self.completer = None self.delims = '' self.basic_quotes: Optional[bytes] = None class _SavedCmd2Env: """cmd2 environment settings that are backed up when entering an interactive Python shell""" def __init__(self) -> None: self.readline_settings = _SavedReadlineSettings() self.readline_module: Optional[ModuleType] = None self.history: List[str] = [] self.sys_stdout: Optional[TextIO] = None self.sys_stdin: Optional[TextIO] = None # Contains data about a disabled command which is used to restore its original functions when the command is enabled DisabledCommand = namedtuple('DisabledCommand', ['command_function', 'help_function', 'completer_function']) if TYPE_CHECKING: # pragma: no cover StaticArgParseBuilder = staticmethod[[], argparse.ArgumentParser] ClassArgParseBuilder = classmethod[Union['Cmd', CommandSet], [], argparse.ArgumentParser] else: StaticArgParseBuilder = staticmethod ClassArgParseBuilder = classmethod class _CommandParsers: """ Create and store all command method argument parsers for a given Cmd instance. Parser creation and retrieval are accomplished through the get() method. """ def __init__(self, cmd: 'Cmd') -> None: self._cmd = cmd # Keyed by the fully qualified method names. This is more reliable than # the methods themselves, since wrapping a method will change its address. self._parsers: Dict[str, argparse.ArgumentParser] = {} @staticmethod def _fully_qualified_name(command_method: CommandFunc) -> str: """Return the fully qualified name of a method or None if a method wasn't passed in.""" try: return f"{command_method.__module__}.{command_method.__qualname__}" except AttributeError: return "" def __contains__(self, command_method: CommandFunc) -> bool: """ Return whether a given method's parser is in self. If the parser does not yet exist, it will be created if applicable. This is basically for checking if a method is argarse-based. """ parser = self.get(command_method) return bool(parser) def get(self, command_method: CommandFunc) -> Optional[argparse.ArgumentParser]: """ Return a given method's parser or None if the method is not argparse-based. If the parser does not yet exist, it will be created. """ full_method_name = self._fully_qualified_name(command_method) if not full_method_name: return None if full_method_name not in self._parsers: if not command_method.__name__.startswith(COMMAND_FUNC_PREFIX): return None command = command_method.__name__[len(COMMAND_FUNC_PREFIX) :] parser_builder = getattr(command_method, constants.CMD_ATTR_ARGPARSER, None) parent = self._cmd.find_commandset_for_command(command) or self._cmd parser = self._cmd._build_parser(parent, parser_builder) if parser is None: return None # argparser defaults the program name to sys.argv[0], but we want it to be the name of our command from .decorators import ( _set_parser_prog, ) _set_parser_prog(parser, command) # If the description has not been set, then use the method docstring if one exists if parser.description is None and hasattr(command_method, '__wrapped__') and command_method.__wrapped__.__doc__: parser.description = strip_doc_annotations(command_method.__wrapped__.__doc__) self._parsers[full_method_name] = parser return self._parsers.get(full_method_name) def remove(self, command_method: CommandFunc) -> None: """Remove a given method's parser if it exists.""" full_method_name = self._fully_qualified_name(command_method) if full_method_name in self._parsers: del self._parsers[full_method_name] class Cmd(cmd.Cmd): """An easy but powerful framework for writing line-oriented command interpreters. Extends the Python Standard Library’s cmd package by adding a lot of useful features to the out of the box configuration. Line-oriented command interpreters are often useful for test harnesses, internal tools, and rapid prototypes. """ DEFAULT_EDITOR = utils.find_editor() INTERNAL_COMMAND_EPILOG = ( "Notes:\n" " This command is for internal use and is not intended to be called from the\n" " command line." ) # Sorting keys for strings ALPHABETICAL_SORT_KEY = utils.norm_fold NATURAL_SORT_KEY = utils.natural_keys def __init__( self, completekey: str = 'tab', stdin: Optional[TextIO] = None, stdout: Optional[TextIO] = None, *, persistent_history_file: str = '', persistent_history_length: int = 1000, startup_script: str = '', silence_startup_script: bool = False, include_py: bool = False, include_ipy: bool = False, allow_cli_args: bool = True, transcript_files: Optional[List[str]] = None, allow_redirection: bool = True, multiline_commands: Optional[List[str]] = None, terminators: Optional[List[str]] = None, shortcuts: Optional[Dict[str, str]] = None, command_sets: Optional[Iterable[CommandSet]] = None, auto_load_commands: bool = True, allow_clipboard: bool = True, suggest_similar_command: bool = False, ) -> None: """An easy but powerful framework for writing line-oriented command interpreters. Extends Python's cmd package. :param completekey: readline name of a completion key, default to Tab :param stdin: alternate input file object, if not specified, sys.stdin is used :param stdout: alternate output file object, if not specified, sys.stdout is used :param persistent_history_file: file path to load a persistent cmd2 command history from :param persistent_history_length: max number of history items to write to the persistent history file :param startup_script: file path to a script to execute at startup :param silence_startup_script: if ``True``, then the startup script's output will be suppressed. Anything written to stderr will still display. :param include_py: should the "py" command be included for an embedded Python shell :param include_ipy: should the "ipy" command be included for an embedded IPython shell :param allow_cli_args: if ``True``, then :meth:`cmd2.Cmd.__init__` will process command line arguments as either commands to be run or, if ``-t`` or ``--test`` are given, transcript files to run. This should be set to ``False`` if your application parses its own command line arguments. :param transcript_files: pass a list of transcript files to be run on initialization. This allows running transcript tests when ``allow_cli_args`` is ``False``. If ``allow_cli_args`` is ``True`` this parameter is ignored. :param allow_redirection: If ``False``, prevent output redirection and piping to shell commands. This parameter prevents redirection and piping, but does not alter parsing behavior. A user can still type redirection and piping tokens, and they will be parsed as such but they won't do anything. :param multiline_commands: list of commands allowed to accept multi-line input :param terminators: list of characters that terminate a command. These are mainly intended for terminating multiline commands, but will also terminate single-line commands. If not supplied, the default is a semicolon. If your app only contains single-line commands and you want terminators to be treated as literals by the parser, then set this to an empty list. :param shortcuts: dictionary containing shortcuts for commands. If not supplied, then defaults to constants.DEFAULT_SHORTCUTS. If you do not want any shortcuts, pass an empty dictionary. :param command_sets: Provide CommandSet instances to load during cmd2 initialization. This allows CommandSets with custom constructor parameters to be loaded. This also allows the a set of CommandSets to be provided when `auto_load_commands` is set to False :param auto_load_commands: If True, cmd2 will check for all subclasses of `CommandSet` that are currently loaded by Python and automatically instantiate and register all commands. If False, CommandSets must be manually installed with `register_command_set`. :param allow_clipboard: If False, cmd2 will disable clipboard interactions :param suggest_similar_command: If ``True``, ``cmd2`` will attempt to suggest the most similar command when the user types a command that does not exist. Default: ``False``. """ # Check if py or ipy need to be disabled in this instance if not include_py: setattr(self, 'do_py', None) if not include_ipy: setattr(self, 'do_ipy', None) # initialize plugin system # needs to be done before we call __init__(0) self._initialize_plugin_system() # Call super class constructor super().__init__(completekey=completekey, stdin=stdin, stdout=stdout) # Attributes which should NOT be dynamically settable via the set command at runtime self.default_to_shell = False # Attempt to run unrecognized commands as shell commands self.allow_redirection = allow_redirection # Security setting to prevent redirection of stdout # Attributes which ARE dynamically settable via the set command at runtime self.always_show_hint = False self.debug = False self.echo = False self.editor = Cmd.DEFAULT_EDITOR self.feedback_to_output = False # Do not include nonessentials in >, | output by default (things like timing) self.quiet = False # Do not suppress nonessential output self.scripts_add_to_history = True # Scripts and pyscripts add commands to history self.timing = False # Prints elapsed time for each command # The maximum number of CompletionItems to display during tab completion. If the number of completion # suggestions exceeds this number, they will be displayed in the typical columnized format and will # not include the description value of the CompletionItems. self.max_completion_items = 50 # A dictionary mapping settable names to their Settable instance self._settables: Dict[str, Settable] = dict() self._always_prefix_settables: bool = False # CommandSet containers self._installed_command_sets: Set[CommandSet] = set() self._cmd_to_command_sets: Dict[str, CommandSet] = {} self.build_settables() # Use as prompt for multiline commands on the 2nd+ line of input self.continuation_prompt = '> ' # Allow access to your application in embedded Python shells and scripts py via self self.self_in_py = False # Commands to exclude from the help menu and tab completion self.hidden_commands = ['eof', '_relative_run_script'] # Initialize history self.persistent_history_file = '' self._persistent_history_length = persistent_history_length self._initialize_history(persistent_history_file) # Commands to exclude from the history command self.exclude_from_history = ['eof', 'history'] # Dictionary of macro names and their values self.macros: Dict[str, Macro] = dict() # Keeps track of typed command history in the Python shell self._py_history: List[str] = [] # The name by which Python environments refer to the PyBridge to call app commands self.py_bridge_name = 'app' # Defines app-specific variables/functions available in Python shells and pyscripts self.py_locals: Dict[str, Any] = dict() # True if running inside a Python shell or pyscript, False otherwise self._in_py = False self.statement_parser = StatementParser( terminators=terminators, multiline_commands=multiline_commands, shortcuts=shortcuts ) # Stores results from the last command run to enable usage of results in Python shells and pyscripts self.last_result: Any = None # Used by run_script command to store current script dir as a LIFO queue to support _relative_run_script command self._script_dir: List[str] = [] # Context manager used to protect critical sections in the main thread from stopping due to a KeyboardInterrupt self.sigint_protection = utils.ContextFlag() # If the current command created a process to pipe to, then this will be a ProcReader object. # Otherwise it will be None. It's used to know when a pipe process can be killed and/or waited upon. self._cur_pipe_proc_reader: Optional[utils.ProcReader] = None # Used to keep track of whether we are redirecting or piping output self._redirecting = False # Used to keep track of whether a continuation prompt is being displayed self._at_continuation_prompt = False # The multiline command currently being typed which is used to tab complete multiline commands. self._multiline_in_progress = '' # Set the header used for the help function's listing of documented functions self.doc_header = "Documented commands (use 'help -v' for verbose/'help ' for details):" # The error that prints when no help information can be found self.help_error = "No help on {}" # The error that prints when a non-existent command is run self.default_error = "{} is not a recognized command, alias, or macro." # If non-empty, this string will be displayed if a broken pipe error occurs self.broken_pipe_warning = '' # Commands that will run at the beginning of the command loop self._startup_commands: List[str] = [] # If a startup script is provided and exists, then execute it in the startup commands if startup_script: startup_script = os.path.abspath(os.path.expanduser(startup_script)) if os.path.exists(startup_script): script_cmd = f"run_script {utils.quote_string(startup_script)}" if silence_startup_script: script_cmd += f" {constants.REDIRECTION_OUTPUT} {os.devnull}" self._startup_commands.append(script_cmd) # Transcript files to run instead of interactive command loop self._transcript_files: Optional[List[str]] = None # Check for command line args if allow_cli_args: parser = argparse_custom.DEFAULT_ARGUMENT_PARSER() parser.add_argument('-t', '--test', action="store_true", help='Test against transcript(s) in FILE (wildcards OK)') callopts, callargs = parser.parse_known_args() # If transcript testing was called for, use other arguments as transcript files if callopts.test: self._transcript_files = callargs # If commands were supplied at invocation, then add them to the command queue elif callargs: self._startup_commands.extend(callargs) elif transcript_files: self._transcript_files = transcript_files # Set the pager(s) for use with the ppaged() method for displaying output using a pager if sys.platform.startswith('win'): self.pager = self.pager_chop = 'more' else: # Here is the meaning of the various flags we are using with the less command: # -S causes lines longer than the screen width to be chopped (truncated) rather than wrapped # -R causes ANSI "style" escape sequences to be output in raw form (i.e. colors are displayed) # -X disables sending the termcap initialization and deinitialization strings to the terminal # -F causes less to automatically exit if the entire file can be displayed on the first screen self.pager = 'less -RXF' self.pager_chop = 'less -SRXF' # This boolean flag stores whether cmd2 will allow clipboard related features self.allow_clipboard = allow_clipboard # This determines the value returned by cmdloop() when exiting the application self.exit_code = 0 # This lock should be acquired before doing any asynchronous changes to the terminal to # ensure the updates to the terminal don't interfere with the input being typed or output # being printed by a command. self.terminal_lock = threading.RLock() # Commands that have been disabled from use. This is to support commands that are only available # during specific states of the application. This dictionary's keys are the command names and its # values are DisabledCommand objects. self.disabled_commands: Dict[str, DisabledCommand] = dict() # If any command has been categorized, then all other commands that haven't been categorized # will display under this section in the help output. self.default_category = 'Uncategorized' # The default key for sorting string results. Its default value performs a case-insensitive alphabetical sort. # If natural sorting is preferred, then set this to NATURAL_SORT_KEY. # cmd2 uses this key for sorting: # command and category names # alias, macro, settable, and shortcut names # tab completion results when self.matches_sorted is False self.default_sort_key = Cmd.ALPHABETICAL_SORT_KEY ############################################################################################################ # The following variables are used by tab completion functions. They are reset each time complete() is run # in _reset_completion_defaults() and it is up to completer functions to set them before returning results. ############################################################################################################ # If True and a single match is returned to complete(), then a space will be appended # if the match appears at the end of the line self.allow_appended_space = True # If True and a single match is returned to complete(), then a closing quote # will be added if there is an unmatched opening quote self.allow_closing_quote = True # An optional hint which prints above tab completion suggestions self.completion_hint = '' # Normally cmd2 uses readline's formatter to columnize the list of completion suggestions. # If a custom format is preferred, write the formatted completions to this string. cmd2 will # then print it instead of the readline format. ANSI style sequences and newlines are supported # when using this value. Even when using formatted_completions, the full matches must still be returned # from your completer function. ArgparseCompleter writes its tab completion tables to this string. self.formatted_completions = '' # Used by complete() for readline tab completion self.completion_matches: List[str] = [] # Use this list if you need to display tab completion suggestions that are different than the actual text # of the matches. For instance, if you are completing strings that contain a common delimiter and you only # want to display the final portion of the matches as the tab completion suggestions. The full matches # still must be returned from your completer function. For an example, look at path_complete() which # uses this to show only the basename of paths as the suggestions. delimiter_complete() also populates # this list. These are ignored if self.formatted_completions is populated. self.display_matches: List[str] = [] # Used by functions like path_complete() and delimiter_complete() to properly # quote matches that are completed in a delimited fashion self.matches_delimited = False # Set to True before returning matches to complete() in cases where matches have already been sorted. # If False, then complete() will sort the matches using self.default_sort_key before they are displayed. # This does not affect self.formatted_completions. self.matches_sorted = False # Command parsers for this Cmd instance. self._command_parsers = _CommandParsers(self) # Add functions decorated to be subcommands self._register_subcommands(self) ############################################################################################################ # The following code block loads CommandSets, verifies command names, and registers subcommands. # This block should appear after all attributes have been created since the registration code # depends on them and it's possible a module's on_register() method may need to access some. ############################################################################################################ # Load modular commands if command_sets: for command_set in command_sets: self.register_command_set(command_set) if auto_load_commands: self._autoload_commands() # Verify commands don't have invalid names (like starting with a shortcut) for cur_cmd in self.get_all_commands(): valid, errmsg = self.statement_parser.is_valid_command(cur_cmd) if not valid: raise ValueError(f"Invalid command name '{cur_cmd}': {errmsg}") self.suggest_similar_command = suggest_similar_command self.default_suggestion_message = "Did you mean {}?" # the current command being executed self.current_command: Optional[Statement] = None def find_commandsets(self, commandset_type: Type[CommandSet], *, subclass_match: bool = False) -> List[CommandSet]: """ Find all CommandSets that match the provided CommandSet type. By default, locates a CommandSet that is an exact type match but may optionally return all CommandSets that are sub-classes of the provided type :param commandset_type: CommandSet sub-class type to search for :param subclass_match: If True, return all sub-classes of provided type, otherwise only search for exact match :return: Matching CommandSets """ return [ cmdset for cmdset in self._installed_command_sets if type(cmdset) == commandset_type or (subclass_match and isinstance(cmdset, commandset_type)) # noqa: E721 ] def find_commandset_for_command(self, command_name: str) -> Optional[CommandSet]: """ Finds the CommandSet that registered the command name :param command_name: command name to search :return: CommandSet that provided the command """ return self._cmd_to_command_sets.get(command_name) def _autoload_commands(self) -> None: """Load modular command definitions.""" # Search for all subclasses of CommandSet, instantiate them if they weren't already provided in the constructor all_commandset_defs = CommandSet.__subclasses__() existing_commandset_types = [type(command_set) for command_set in self._installed_command_sets] def load_commandset_by_type(commandset_types: List[Type[CommandSet]]) -> None: for cmdset_type in commandset_types: # check if the type has sub-classes. We will only auto-load leaf class types. subclasses = cmdset_type.__subclasses__() if subclasses: load_commandset_by_type(subclasses) else: init_sig = inspect.signature(cmdset_type.__init__) if not ( cmdset_type in existing_commandset_types or len(init_sig.parameters) != 1 or 'self' not in init_sig.parameters ): cmdset = cmdset_type() self.register_command_set(cmdset) load_commandset_by_type(all_commandset_defs) def register_command_set(self, cmdset: CommandSet) -> None: """ Installs a CommandSet, loading all commands defined in the CommandSet :param cmdset: CommandSet to load """ existing_commandset_types = [type(command_set) for command_set in self._installed_command_sets] if type(cmdset) in existing_commandset_types: raise CommandSetRegistrationError('CommandSet ' + type(cmdset).__name__ + ' is already installed') all_settables = self.settables if self.always_prefix_settables: if not cmdset.settable_prefix.strip(): raise CommandSetRegistrationError('CommandSet settable prefix must not be empty') for key in cmdset.settables.keys(): prefixed_name = f'{cmdset.settable_prefix}.{key}' if prefixed_name in all_settables: raise CommandSetRegistrationError(f'Duplicate settable: {key}') else: for key in cmdset.settables.keys(): if key in all_settables: raise CommandSetRegistrationError(f'Duplicate settable {key} is already registered') cmdset.on_register(self) methods = cast( List[Tuple[str, Callable[..., Any]]], inspect.getmembers( cmdset, predicate=lambda meth: isinstance(meth, Callable) # type: ignore[arg-type] and hasattr(meth, '__name__') and meth.__name__.startswith(COMMAND_FUNC_PREFIX), ), ) default_category = getattr(cmdset, CLASS_ATTR_DEFAULT_HELP_CATEGORY, None) installed_attributes = [] try: for cmd_func_name, command_method in methods: command = cmd_func_name[len(COMMAND_FUNC_PREFIX) :] self._install_command_function(cmd_func_name, command_method, type(cmdset).__name__) installed_attributes.append(cmd_func_name) completer_func_name = COMPLETER_FUNC_PREFIX + command cmd_completer = getattr(cmdset, completer_func_name, None) if cmd_completer is not None: self._install_completer_function(command, cmd_completer) installed_attributes.append(completer_func_name) help_func_name = HELP_FUNC_PREFIX + command cmd_help = getattr(cmdset, help_func_name, None) if cmd_help is not None: self._install_help_function(command, cmd_help) installed_attributes.append(help_func_name) self._cmd_to_command_sets[command] = cmdset if default_category and not hasattr(command_method, constants.CMD_ATTR_HELP_CATEGORY): utils.categorize(command_method, default_category) self._installed_command_sets.add(cmdset) self._register_subcommands(cmdset) cmdset.on_registered() except Exception: cmdset.on_unregister() for attrib in installed_attributes: delattr(self, attrib) if cmdset in self._installed_command_sets: self._installed_command_sets.remove(cmdset) if cmdset in self._cmd_to_command_sets.values(): self._cmd_to_command_sets = {key: val for key, val in self._cmd_to_command_sets.items() if val is not cmdset} cmdset.on_unregistered() raise def _build_parser( self, parent: CommandParent, parser_builder: Optional[ Union[ argparse.ArgumentParser, Callable[[], argparse.ArgumentParser], StaticArgParseBuilder, ClassArgParseBuilder, ] ], ) -> Optional[argparse.ArgumentParser]: parser: Optional[argparse.ArgumentParser] = None if isinstance(parser_builder, staticmethod): parser = parser_builder.__func__() elif isinstance(parser_builder, classmethod): parser = parser_builder.__func__(parent if not None else self) # type: ignore[arg-type] elif callable(parser_builder): parser = parser_builder() elif isinstance(parser_builder, argparse.ArgumentParser): parser = copy.deepcopy(parser_builder) return parser def _install_command_function(self, command_func_name: str, command_method: CommandFunc, context: str = '') -> None: """ Install a new command function into the CLI. :param command_func_name: name of command function to add This points to the command method and may differ from the method's name if it's being used as a synonym. (e.g. do_exit = do_quit) :param command_method: the actual command method which runs when the command function is called :param context: optional info to provide in error message. (e.g. class this function belongs to) :raises CommandSetRegistrationError: if the command function fails to install """ # command_func_name must begin with COMMAND_FUNC_PREFIX to be identified as a command by cmd2. if not command_func_name.startswith(COMMAND_FUNC_PREFIX): raise CommandSetRegistrationError(f"{command_func_name} does not begin with '{COMMAND_FUNC_PREFIX}'") # command_method must start with COMMAND_FUNC_PREFIX for use in self._command_parsers. if not command_method.__name__.startswith(COMMAND_FUNC_PREFIX): raise CommandSetRegistrationError(f"{command_method.__name__} does not begin with '{COMMAND_FUNC_PREFIX}'") command = command_func_name[len(COMMAND_FUNC_PREFIX) :] # Make sure command function doesn't share name with existing attribute if hasattr(self, command_func_name): raise CommandSetRegistrationError(f'Attribute already exists: {command_func_name} ({context})') # Check if command has an invalid name valid, errmsg = self.statement_parser.is_valid_command(command) if not valid: raise CommandSetRegistrationError(f"Invalid command name '{command}': {errmsg}") # Check if command shares a name with an alias if command in self.aliases: self.pwarning(f"Deleting alias '{command}' because it shares its name with a new command") del self.aliases[command] # Check if command shares a name with a macro if command in self.macros: self.pwarning(f"Deleting macro '{command}' because it shares its name with a new command") del self.macros[command] setattr(self, command_func_name, command_method) def _install_completer_function(self, cmd_name: str, cmd_completer: CompleterFunc) -> None: completer_func_name = COMPLETER_FUNC_PREFIX + cmd_name if hasattr(self, completer_func_name): raise CommandSetRegistrationError(f'Attribute already exists: {completer_func_name}') setattr(self, completer_func_name, cmd_completer) def _install_help_function(self, cmd_name: str, cmd_help: Callable[..., None]) -> None: help_func_name = HELP_FUNC_PREFIX + cmd_name if hasattr(self, help_func_name): raise CommandSetRegistrationError(f'Attribute already exists: {help_func_name}') setattr(self, help_func_name, cmd_help) def unregister_command_set(self, cmdset: CommandSet) -> None: """ Uninstalls a CommandSet and unloads all associated commands :param cmdset: CommandSet to uninstall """ if cmdset in self._installed_command_sets: self._check_uninstallable(cmdset) cmdset.on_unregister() self._unregister_subcommands(cmdset) methods: List[Tuple[str, Callable[..., Any]]] = inspect.getmembers( cmdset, predicate=lambda meth: isinstance(meth, Callable) # type: ignore[arg-type] and hasattr(meth, '__name__') and meth.__name__.startswith(COMMAND_FUNC_PREFIX), ) for cmd_func_name, command_method in methods: command = cmd_func_name[len(COMMAND_FUNC_PREFIX) :] # Enable the command before uninstalling it to make sure we remove both # the real functions and the ones used by the DisabledCommand object. if command in self.disabled_commands: self.enable_command(command) if command in self._cmd_to_command_sets: del self._cmd_to_command_sets[command] # Only remove the parser if this is the actual # command since command synonyms don't own it. if cmd_func_name == command_method.__name__: self._command_parsers.remove(command_method) if hasattr(self, COMPLETER_FUNC_PREFIX + command): delattr(self, COMPLETER_FUNC_PREFIX + command) if hasattr(self, HELP_FUNC_PREFIX + command): delattr(self, HELP_FUNC_PREFIX + command) delattr(self, cmd_func_name) cmdset.on_unregistered() self._installed_command_sets.remove(cmdset) def _check_uninstallable(self, cmdset: CommandSet) -> None: def check_parser_uninstallable(parser: argparse.ArgumentParser) -> None: for action in parser._actions: if isinstance(action, argparse._SubParsersAction): for subparser in action.choices.values(): attached_cmdset = getattr(subparser, constants.PARSER_ATTR_COMMANDSET, None) if attached_cmdset is not None and attached_cmdset is not cmdset: raise CommandSetRegistrationError( 'Cannot uninstall CommandSet when another CommandSet depends on it' ) check_parser_uninstallable(subparser) break methods: List[Tuple[str, Callable[..., Any]]] = inspect.getmembers( cmdset, predicate=lambda meth: isinstance(meth, Callable) # type: ignore[arg-type] and hasattr(meth, '__name__') and meth.__name__.startswith(COMMAND_FUNC_PREFIX), ) for cmd_func_name, command_method in methods: # We only need to check if it's safe to remove the parser if this # is the actual command since command synonyms don't own it. if cmd_func_name == command_method.__name__: command_parser = self._command_parsers.get(command_method) if command_parser is not None: check_parser_uninstallable(command_parser) def _register_subcommands(self, cmdset: Union[CommandSet, 'Cmd']) -> None: """ Register subcommands with their base command :param cmdset: CommandSet or cmd2.Cmd subclass containing subcommands """ if not (cmdset is self or cmdset in self._installed_command_sets): raise CommandSetRegistrationError('Cannot register subcommands with an unregistered CommandSet') # find methods that have the required attributes necessary to be recognized as a sub-command methods = inspect.getmembers( cmdset, predicate=lambda meth: isinstance(meth, Callable) # type: ignore[arg-type] and hasattr(meth, constants.SUBCMD_ATTR_NAME) and hasattr(meth, constants.SUBCMD_ATTR_COMMAND) and hasattr(meth, constants.CMD_ATTR_ARGPARSER), ) # iterate through all matching methods for method_name, method in methods: subcommand_name: str = getattr(method, constants.SUBCMD_ATTR_NAME) full_command_name: str = getattr(method, constants.SUBCMD_ATTR_COMMAND) subcmd_parser_builder = getattr(method, constants.CMD_ATTR_ARGPARSER) subcommand_valid, errmsg = self.statement_parser.is_valid_command(subcommand_name, is_subcommand=True) if not subcommand_valid: raise CommandSetRegistrationError(f'Subcommand {str(subcommand_name)} is not valid: {errmsg}') command_tokens = full_command_name.split() command_name = command_tokens[0] subcommand_names = command_tokens[1:] # Search for the base command function and verify it has an argparser defined if command_name in self.disabled_commands: command_func = self.disabled_commands[command_name].command_function else: command_func = self.cmd_func(command_name) if command_func is None: raise CommandSetRegistrationError( f"Could not find command '{command_name}' needed by subcommand: {str(method)}" ) command_parser = self._command_parsers.get(command_func) if command_parser is None: raise CommandSetRegistrationError( f"Could not find argparser for command '{command_name}' needed by subcommand: {str(method)}" ) def find_subcommand(action: argparse.ArgumentParser, subcmd_names: List[str]) -> argparse.ArgumentParser: if not subcmd_names: return action cur_subcmd = subcmd_names.pop(0) for sub_action in action._actions: if isinstance(sub_action, argparse._SubParsersAction): for choice_name, choice in sub_action.choices.items(): if choice_name == cur_subcmd: return find_subcommand(choice, subcmd_names) break raise CommandSetRegistrationError(f"Could not find subcommand '{full_command_name}'") target_parser = find_subcommand(command_parser, subcommand_names) subcmd_parser = cast(argparse.ArgumentParser, self._build_parser(cmdset, subcmd_parser_builder)) from .decorators import ( _set_parser_prog, ) _set_parser_prog(subcmd_parser, f'{command_name} {subcommand_name}') if subcmd_parser.description is None and method.__doc__: subcmd_parser.description = strip_doc_annotations(method.__doc__) for action in target_parser._actions: if isinstance(action, argparse._SubParsersAction): # Get the kwargs for add_parser() add_parser_kwargs = getattr(method, constants.SUBCMD_ATTR_ADD_PARSER_KWARGS, {}) # Set subcmd_parser as the parent to the parser we're creating to get its arguments add_parser_kwargs['parents'] = [subcmd_parser] # argparse only copies actions from a parent and not the following settings. # To retain these settings, we will copy them from subcmd_parser and pass them # as ArgumentParser constructor arguments to add_parser(). add_parser_kwargs['prog'] = subcmd_parser.prog add_parser_kwargs['usage'] = subcmd_parser.usage add_parser_kwargs['description'] = subcmd_parser.description add_parser_kwargs['epilog'] = subcmd_parser.epilog add_parser_kwargs['formatter_class'] = subcmd_parser.formatter_class add_parser_kwargs['prefix_chars'] = subcmd_parser.prefix_chars add_parser_kwargs['fromfile_prefix_chars'] = subcmd_parser.fromfile_prefix_chars add_parser_kwargs['argument_default'] = subcmd_parser.argument_default add_parser_kwargs['conflict_handler'] = subcmd_parser.conflict_handler add_parser_kwargs['allow_abbrev'] = subcmd_parser.allow_abbrev # Set add_help to False and use whatever help option subcmd_parser already has add_parser_kwargs['add_help'] = False attached_parser = action.add_parser(subcommand_name, **add_parser_kwargs) # Set the subcommand handler defaults = {constants.NS_ATTR_SUBCMD_HANDLER: method} attached_parser.set_defaults(**defaults) # Copy value for custom ArgparseCompleter type, which will be None if not present on subcmd_parser attached_parser.set_ap_completer_type(subcmd_parser.get_ap_completer_type()) # type: ignore[attr-defined] # Set what instance the handler is bound to setattr(attached_parser, constants.PARSER_ATTR_COMMANDSET, cmdset) break def _unregister_subcommands(self, cmdset: Union[CommandSet, 'Cmd']) -> None: """ Unregister subcommands from their base command :param cmdset: CommandSet containing subcommands """ if not (cmdset is self or cmdset in self._installed_command_sets): raise CommandSetRegistrationError('Cannot unregister subcommands with an unregistered CommandSet') # find methods that have the required attributes necessary to be recognized as a sub-command methods = inspect.getmembers( cmdset, predicate=lambda meth: isinstance(meth, Callable) # type: ignore[arg-type] and hasattr(meth, constants.SUBCMD_ATTR_NAME) and hasattr(meth, constants.SUBCMD_ATTR_COMMAND) and hasattr(meth, constants.CMD_ATTR_ARGPARSER), ) # iterate through all matching methods for method_name, method in methods: subcommand_name = getattr(method, constants.SUBCMD_ATTR_NAME) command_name = getattr(method, constants.SUBCMD_ATTR_COMMAND) # Search for the base command function and verify it has an argparser defined if command_name in self.disabled_commands: command_func = self.disabled_commands[command_name].command_function else: command_func = self.cmd_func(command_name) if command_func is None: # pragma: no cover # This really shouldn't be possible since _register_subcommands would prevent this from happening # but keeping in case it does for some strange reason raise CommandSetRegistrationError( f"Could not find command '{command_name}' needed by subcommand: {str(method)}" ) command_parser = self._command_parsers.get(command_func) if command_parser is None: # pragma: no cover # This really shouldn't be possible since _register_subcommands would prevent this from happening # but keeping in case it does for some strange reason raise CommandSetRegistrationError( f"Could not find argparser for command '{command_name}' needed by subcommand: {str(method)}" ) for action in command_parser._actions: if isinstance(action, argparse._SubParsersAction): action.remove_parser(subcommand_name) # type: ignore[arg-type,attr-defined] break @property def always_prefix_settables(self) -> bool: """ Flags whether CommandSet settable values should always be prefixed :return: True if CommandSet settable values will always be prefixed. False if not. """ return self._always_prefix_settables @always_prefix_settables.setter def always_prefix_settables(self, new_value: bool) -> None: """ Set whether CommandSet settable values should always be prefixed. :param new_value: True if CommandSet settable values should always be prefixed. False if not. :raises ValueError: If a registered CommandSet does not have a defined prefix """ if not self._always_prefix_settables and new_value: for cmd_set in self._installed_command_sets: if not cmd_set.settable_prefix: raise ValueError( f'Cannot force settable prefixes. CommandSet {cmd_set.__class__.__name__} does ' f'not have a settable prefix defined.' ) self._always_prefix_settables = new_value @property def settables(self) -> Mapping[str, Settable]: """ Get all available user-settable attributes. This includes settables defined in installed CommandSets :return: Mapping from attribute-name to Settable of all user-settable attributes from """ all_settables = dict(self._settables) for cmd_set in self._installed_command_sets: cmdset_settables = cmd_set.settables for settable_name, settable in cmdset_settables.items(): if self.always_prefix_settables: all_settables[f'{cmd_set.settable_prefix}.{settable_name}'] = settable else: all_settables[settable_name] = settable return all_settables def add_settable(self, settable: Settable) -> None: """ Add a settable parameter to ``self.settables`` :param settable: Settable object being added """ if not self.always_prefix_settables: if settable.name in self.settables.keys() and settable.name not in self._settables.keys(): raise KeyError(f'Duplicate settable: {settable.name}') self._settables[settable.name] = settable def remove_settable(self, name: str) -> None: """ Convenience method for removing a settable parameter from ``self.settables`` :param name: name of the settable being removed :raises: KeyError if the Settable matches this name """ try: del self._settables[name] except KeyError: raise KeyError(name + " is not a settable parameter") def build_settables(self) -> None: """Create the dictionary of user-settable parameters""" def get_allow_style_choices(cli_self: Cmd) -> List[str]: """Used to tab complete allow_style values""" return [val.name.lower() for val in ansi.AllowStyle] def allow_style_type(value: str) -> ansi.AllowStyle: """Converts a string value into an ansi.AllowStyle""" try: return ansi.AllowStyle[value.upper()] except KeyError: raise ValueError( f"must be {ansi.AllowStyle.ALWAYS}, {ansi.AllowStyle.NEVER}, or " f"{ansi.AllowStyle.TERMINAL} (case-insensitive)" ) self.add_settable( Settable( 'allow_style', allow_style_type, 'Allow ANSI text style sequences in output (valid values: ' f'{ansi.AllowStyle.ALWAYS}, {ansi.AllowStyle.NEVER}, {ansi.AllowStyle.TERMINAL})', self, choices_provider=cast(ChoicesProviderFunc, get_allow_style_choices), ) ) self.add_settable( Settable('always_show_hint', bool, 'Display tab completion hint even when completion suggestions print', self) ) self.add_settable(Settable('debug', bool, "Show full traceback on exception", self)) self.add_settable(Settable('echo', bool, "Echo command issued into output", self)) self.add_settable(Settable('editor', str, "Program used by 'edit'", self)) self.add_settable(Settable('feedback_to_output', bool, "Include nonessentials in '|', '>' results", self)) self.add_settable( Settable('max_completion_items', int, "Maximum number of CompletionItems to display during tab completion", self) ) self.add_settable(Settable('quiet', bool, "Don't print nonessential feedback", self)) self.add_settable(Settable('scripts_add_to_history', bool, 'Scripts and pyscripts add commands to history', self)) self.add_settable(Settable('timing', bool, "Report execution times", self)) # ----- Methods related to presenting output to the user ----- @property def allow_style(self) -> ansi.AllowStyle: """Read-only property needed to support do_set when it reads allow_style""" return ansi.allow_style @allow_style.setter def allow_style(self, new_val: ansi.AllowStyle) -> None: """Setter property needed to support do_set when it updates allow_style""" ansi.allow_style = new_val def _completion_supported(self) -> bool: """Return whether tab completion is supported""" return self.use_rawinput and bool(self.completekey) and rl_type != RlType.NONE @property def visible_prompt(self) -> str: """Read-only property to get the visible prompt with any ANSI style escape codes stripped. Used by transcript testing to make it easier and more reliable when users are doing things like coloring the prompt using ANSI color codes. :return: prompt stripped of any ANSI escape codes """ return ansi.strip_style(self.prompt) def print_to( self, dest: IO[str], msg: Any, *, end: str = '\n', style: Optional[Callable[[str], str]] = None, ) -> None: """ Print message to a given file object. :param dest: the file object being written to :param msg: object to print :param end: string appended after the end of the message, default a newline :param style: optional style function to format msg with (e.g. ansi.style_success) """ final_msg = style(msg) if style is not None else msg try: ansi.style_aware_write(dest, f'{final_msg}{end}') except BrokenPipeError: # This occurs if a command's output is being piped to another # process and that process closes before the command is # finished. If you would like your application to print a # warning message, then set the broken_pipe_warning attribute # to the message you want printed. if self.broken_pipe_warning: sys.stderr.write(self.broken_pipe_warning) def poutput(self, msg: Any = '', *, end: str = '\n') -> None: """Print message to self.stdout and appends a newline by default :param msg: object to print :param end: string appended after the end of the message, default a newline """ self.print_to(self.stdout, msg, end=end) def perror(self, msg: Any = '', *, end: str = '\n', apply_style: bool = True) -> None: """Print message to sys.stderr :param msg: object to print :param end: string appended after the end of the message, default a newline :param apply_style: If True, then ansi.style_error will be applied to the message text. Set to False in cases where the message text already has the desired style. Defaults to True. """ self.print_to(sys.stderr, msg, end=end, style=ansi.style_error if apply_style else None) def psuccess(self, msg: Any = '', *, end: str = '\n') -> None: """Wraps poutput, but applies ansi.style_success by default :param msg: object to print :param end: string appended after the end of the message, default a newline """ msg = ansi.style_success(msg) self.poutput(msg, end=end) def pwarning(self, msg: Any = '', *, end: str = '\n') -> None: """Wraps perror, but applies ansi.style_warning by default :param msg: object to print :param end: string appended after the end of the message, default a newline """ msg = ansi.style_warning(msg) self.perror(msg, end=end, apply_style=False) def pexcept(self, msg: Any, *, end: str = '\n', apply_style: bool = True) -> None: """Print Exception message to sys.stderr. If debug is true, print exception traceback if one exists. :param msg: message or Exception to print :param end: string appended after the end of the message, default a newline :param apply_style: If True, then ansi.style_error will be applied to the message text. Set to False in cases where the message text already has the desired style. Defaults to True. """ if self.debug and sys.exc_info() != (None, None, None): import traceback traceback.print_exc() if isinstance(msg, Exception): final_msg = f"EXCEPTION of type '{type(msg).__name__}' occurred with message: {msg}" else: final_msg = str(msg) if apply_style: final_msg = ansi.style_error(final_msg) if not self.debug and 'debug' in self.settables: warning = "\nTo enable full traceback, run the following command: 'set debug true'" final_msg += ansi.style_warning(warning) self.perror(final_msg, end=end, apply_style=False) def pfeedback(self, msg: Any, *, end: str = '\n') -> None: """For printing nonessential feedback. Can be silenced with `quiet`. Inclusion in redirected output is controlled by `feedback_to_output`. :param msg: object to print :param end: string appended after the end of the message, default a newline """ if not self.quiet: if self.feedback_to_output: self.poutput(msg, end=end) else: self.perror(msg, end=end, apply_style=False) def ppaged(self, msg: Any, *, end: str = '\n', chop: bool = False) -> None: """Print output using a pager if it would go off screen and stdout isn't currently being redirected. Never uses a pager inside a script (Python or text) or when output is being redirected or piped or when stdout or stdin are not a fully functional terminal. :param msg: object to print :param end: string appended after the end of the message, default a newline :param chop: True -> causes lines longer than the screen width to be chopped (truncated) rather than wrapped - truncated text is still accessible by scrolling with the right & left arrow keys - chopping is ideal for displaying wide tabular data as is done in utilities like pgcli False -> causes lines longer than the screen width to wrap to the next line - wrapping is ideal when you want to keep users from having to use horizontal scrolling WARNING: On Windows, the text always wraps regardless of what the chop argument is set to """ # Attempt to detect if we are not running within a fully functional terminal. # Don't try to use the pager when being run by a continuous integration system like Jenkins + pexpect. functional_terminal = False if self.stdin.isatty() and self.stdout.isatty(): if sys.platform.startswith('win') or os.environ.get('TERM') is not None: functional_terminal = True # Don't attempt to use a pager that can block if redirecting or running a script (either text or Python). # Also only attempt to use a pager if actually running in a real fully functional terminal. if functional_terminal and not self._redirecting and not self.in_pyscript() and not self.in_script(): final_msg = f"{msg}{end}" if ansi.allow_style == ansi.AllowStyle.NEVER: final_msg = ansi.strip_style(final_msg) pager = self.pager if chop: pager = self.pager_chop try: # Prevent KeyboardInterrupts while in the pager. The pager application will # still receive the SIGINT since it is in the same process group as us. with self.sigint_protection: import subprocess pipe_proc = subprocess.Popen(pager, shell=True, stdin=subprocess.PIPE, stdout=self.stdout) pipe_proc.communicate(final_msg.encode('utf-8', 'replace')) except BrokenPipeError: # This occurs if a command's output is being piped to another process and that process closes before the # command is finished. If you would like your application to print a warning message, then set the # broken_pipe_warning attribute to the message you want printed.` if self.broken_pipe_warning: sys.stderr.write(self.broken_pipe_warning) else: self.poutput(msg, end=end) # ----- Methods related to tab completion ----- def _reset_completion_defaults(self) -> None: """ Resets tab completion settings Needs to be called each time readline runs tab completion """ self.allow_appended_space = True self.allow_closing_quote = True self.completion_hint = '' self.formatted_completions = '' self.completion_matches = [] self.display_matches = [] self.matches_delimited = False self.matches_sorted = False if rl_type == RlType.GNU: readline.set_completion_display_matches_hook(self._display_matches_gnu_readline) elif rl_type == RlType.PYREADLINE: readline.rl.mode._display_completions = self._display_matches_pyreadline def tokens_for_completion(self, line: str, begidx: int, endidx: int) -> Tuple[List[str], List[str]]: """Used by tab completion functions to get all tokens through the one being completed. :param line: the current input line with leading whitespace removed :param begidx: the beginning index of the prefix text :param endidx: the ending index of the prefix text :return: A 2 item tuple where the items are **On Success** - tokens: list of unquoted tokens - this is generally the list needed for tab completion functions - raw_tokens: list of tokens with any quotes preserved = this can be used to know if a token was quoted or is missing a closing quote Both lists are guaranteed to have at least 1 item. The last item in both lists is the token being tab completed **On Failure** - Two empty lists """ import copy unclosed_quote = '' quotes_to_try = copy.copy(constants.QUOTES) tmp_line = line[:endidx] tmp_endidx = endidx # Parse the line into tokens while True: try: initial_tokens = shlex_split(tmp_line[:tmp_endidx]) # If the cursor is at an empty token outside of a quoted string, # then that is the token being completed. Add it to the list. if not unclosed_quote and begidx == tmp_endidx: initial_tokens.append('') break except ValueError as ex: # Make sure the exception was due to an unclosed quote and # we haven't exhausted the closing quotes to try if str(ex) == "No closing quotation" and quotes_to_try: # Add a closing quote and try to parse again unclosed_quote = quotes_to_try[0] quotes_to_try = quotes_to_try[1:] tmp_line = line[:endidx] tmp_line += unclosed_quote tmp_endidx = endidx + 1 else: # pragma: no cover # The parsing error is not caused by unclosed quotes. # Return empty lists since this means the line is malformed. return [], [] # Further split tokens on punctuation characters raw_tokens = self.statement_parser.split_on_punctuation(initial_tokens) # Save the unquoted tokens tokens = [utils.strip_quotes(cur_token) for cur_token in raw_tokens] # If the token being completed had an unclosed quote, we need # to remove the closing quote that was added in order for it # to match what was on the command line. if unclosed_quote: raw_tokens[-1] = raw_tokens[-1][:-1] return tokens, raw_tokens def basic_complete( self, text: str, line: str, begidx: int, endidx: int, match_against: Iterable[str], ) -> List[str]: """ Basic tab completion function that matches against a list of strings without considering line contents or cursor position. The args required by this function are defined in the header of Python's cmd.py. :param text: the string prefix we are attempting to match (all matches must begin with it) :param line: the current input line with leading whitespace removed :param begidx: the beginning index of the prefix text :param endidx: the ending index of the prefix text :param match_against: the strings being matched against :return: a list of possible tab completions """ return [cur_match for cur_match in match_against if cur_match.startswith(text)] def delimiter_complete( self, text: str, line: str, begidx: int, endidx: int, match_against: Iterable[str], delimiter: str, ) -> List[str]: """ Performs tab completion against a list but each match is split on a delimiter and only the portion of the match being tab completed is shown as the completion suggestions. This is useful if you match against strings that are hierarchical in nature and have a common delimiter. An easy way to illustrate this concept is path completion since paths are just directories/files delimited by a slash. If you are tab completing items in /home/user you don't get the following as suggestions: /home/user/file.txt /home/user/program.c /home/user/maps/ /home/user/cmd2.py Instead you are shown: file.txt program.c maps/ cmd2.py For a large set of data, this can be visually more pleasing and easier to search. Another example would be strings formatted with the following syntax: company::department::name In this case the delimiter would be :: and the user could easily narrow down what they are looking for if they were only shown suggestions in the category they are at in the string. :param text: the string prefix we are attempting to match (all matches must begin with it) :param line: the current input line with leading whitespace removed :param begidx: the beginning index of the prefix text :param endidx: the ending index of the prefix text :param match_against: the list being matched against :param delimiter: what delimits each portion of the matches (ex: paths are delimited by a slash) :return: a list of possible tab completions """ matches = self.basic_complete(text, line, begidx, endidx, match_against) # Display only the portion of the match that's being completed based on delimiter if matches: # Set this to True for proper quoting of matches with spaces self.matches_delimited = True # Get the common beginning for the matches common_prefix = os.path.commonprefix(matches) prefix_tokens = common_prefix.split(delimiter) # Calculate what portion of the match we are completing display_token_index = 0 if prefix_tokens: display_token_index = len(prefix_tokens) - 1 # Get this portion for each match and store them in self.display_matches for cur_match in matches: match_tokens = cur_match.split(delimiter) display_token = match_tokens[display_token_index] if not display_token: display_token = delimiter self.display_matches.append(display_token) return matches def flag_based_complete( self, text: str, line: str, begidx: int, endidx: int, flag_dict: Dict[str, Union[Iterable[str], CompleterFunc]], *, all_else: Union[None, Iterable[str], CompleterFunc] = None, ) -> List[str]: """Tab completes based on a particular flag preceding the token being completed. :param text: the string prefix we are attempting to match (all matches must begin with it) :param line: the current input line with leading whitespace removed :param begidx: the beginning index of the prefix text :param endidx: the ending index of the prefix text :param flag_dict: dictionary whose structure is the following: `keys` - flags (ex: -c, --create) that result in tab completion for the next argument in the command line `values` - there are two types of values: 1. iterable list of strings to match against (dictionaries, lists, etc.) 2. function that performs tab completion (ex: path_complete) :param all_else: an optional parameter for tab completing any token that isn't preceded by a flag in flag_dict :return: a list of possible tab completions """ # Get all tokens through the one being completed tokens, _ = self.tokens_for_completion(line, begidx, endidx) if not tokens: # pragma: no cover return [] completions_matches = [] match_against = all_else # Must have at least 2 args for a flag to precede the token being completed if len(tokens) > 1: flag = tokens[-2] if flag in flag_dict: match_against = flag_dict[flag] # Perform tab completion using an Iterable if isinstance(match_against, Iterable): completions_matches = self.basic_complete(text, line, begidx, endidx, match_against) # Perform tab completion using a function elif callable(match_against): completions_matches = match_against(text, line, begidx, endidx) return completions_matches def index_based_complete( self, text: str, line: str, begidx: int, endidx: int, index_dict: Mapping[int, Union[Iterable[str], CompleterFunc]], *, all_else: Optional[Union[Iterable[str], CompleterFunc]] = None, ) -> List[str]: """Tab completes based on a fixed position in the input string. :param text: the string prefix we are attempting to match (all matches must begin with it) :param line: the current input line with leading whitespace removed :param begidx: the beginning index of the prefix text :param endidx: the ending index of the prefix text :param index_dict: dictionary whose structure is the following: `keys` - 0-based token indexes into command line that determine which tokens perform tab completion `values` - there are two types of values: 1. iterable list of strings to match against (dictionaries, lists, etc.) 2. function that performs tab completion (ex: path_complete) :param all_else: an optional parameter for tab completing any token that isn't at an index in index_dict :return: a list of possible tab completions """ # Get all tokens through the one being completed tokens, _ = self.tokens_for_completion(line, begidx, endidx) if not tokens: # pragma: no cover return [] matches = [] # Get the index of the token being completed index = len(tokens) - 1 # Check if token is at an index in the dictionary match_against: Optional[Union[Iterable[str], CompleterFunc]] if index in index_dict: match_against = index_dict[index] else: match_against = all_else # Perform tab completion using a Iterable if isinstance(match_against, Iterable): matches = self.basic_complete(text, line, begidx, endidx, match_against) # Perform tab completion using a function elif callable(match_against): matches = match_against(text, line, begidx, endidx) return matches def path_complete( self, text: str, line: str, begidx: int, endidx: int, *, path_filter: Optional[Callable[[str], bool]] = None ) -> List[str]: """Performs completion of local file system paths :param text: the string prefix we are attempting to match (all matches must begin with it) :param line: the current input line with leading whitespace removed :param begidx: the beginning index of the prefix text :param endidx: the ending index of the prefix text :param path_filter: optional filter function that determines if a path belongs in the results this function takes a path as its argument and returns True if the path should be kept in the results :return: a list of possible tab completions """ # Used to complete ~ and ~user strings def complete_users() -> List[str]: users = [] # Windows lacks the pwd module so we can't get a list of users. # Instead we will return a result once the user enters text that # resolves to an existing home directory. if sys.platform.startswith('win'): expanded_path = os.path.expanduser(text) if os.path.isdir(expanded_path): user = text if add_trailing_sep_if_dir: user += os.path.sep users.append(user) else: import pwd # Iterate through a list of users from the password database for cur_pw in pwd.getpwall(): # Check if the user has an existing home dir if os.path.isdir(cur_pw.pw_dir): # Add a ~ to the user to match against text cur_user = '~' + cur_pw.pw_name if cur_user.startswith(text): if add_trailing_sep_if_dir: cur_user += os.path.sep users.append(cur_user) if users: # We are returning ~user strings that resolve to directories, # so don't append a space or quote in the case of a single result. self.allow_appended_space = False self.allow_closing_quote = False return users # Determine if a trailing separator should be appended to directory completions add_trailing_sep_if_dir = False if endidx == len(line) or (endidx < len(line) and line[endidx] != os.path.sep): add_trailing_sep_if_dir = True # Used to replace cwd in the final results cwd = os.getcwd() cwd_added = False # Used to replace expanded user path in final result orig_tilde_path = '' expanded_tilde_path = '' # If the search text is blank, then search in the CWD for * if not text: search_str = os.path.join(os.getcwd(), '*') cwd_added = True else: # Purposely don't match any path containing wildcards wildcards = ['*', '?'] for wildcard in wildcards: if wildcard in text: return [] # Start the search string search_str = text + '*' # Handle tilde expansion and completion if text.startswith('~'): sep_index = text.find(os.path.sep, 1) # If there is no slash, then the user is still completing the user after the tilde if sep_index == -1: return complete_users() # Otherwise expand the user dir else: search_str = os.path.expanduser(search_str) # Get what we need to restore the original tilde path later orig_tilde_path = text[:sep_index] expanded_tilde_path = os.path.expanduser(orig_tilde_path) # If the search text does not have a directory, then use the cwd elif not os.path.dirname(text): search_str = os.path.join(os.getcwd(), search_str) cwd_added = True # Find all matching path completions matches = glob.glob(search_str) # Filter out results that don't belong if path_filter is not None: matches = [c for c in matches if path_filter(c)] if matches: # Set this to True for proper quoting of paths with spaces self.matches_delimited = True # Don't append a space or closing quote to directory if len(matches) == 1 and os.path.isdir(matches[0]): self.allow_appended_space = False self.allow_closing_quote = False # Sort the matches before any trailing slashes are added matches.sort(key=self.default_sort_key) self.matches_sorted = True # Build display_matches and add a slash to directories for index, cur_match in enumerate(matches): # Display only the basename of this path in the tab completion suggestions self.display_matches.append(os.path.basename(cur_match)) # Add a separator after directories if the next character isn't already a separator if os.path.isdir(cur_match) and add_trailing_sep_if_dir: matches[index] += os.path.sep self.display_matches[index] += os.path.sep # Remove cwd if it was added to match the text readline expects if cwd_added: if cwd == os.path.sep: to_replace = cwd else: to_replace = cwd + os.path.sep matches = [cur_path.replace(to_replace, '', 1) for cur_path in matches] # Restore the tilde string if we expanded one to match the text readline expects if expanded_tilde_path: matches = [cur_path.replace(expanded_tilde_path, orig_tilde_path, 1) for cur_path in matches] return matches def shell_cmd_complete(self, text: str, line: str, begidx: int, endidx: int, *, complete_blank: bool = False) -> List[str]: """Performs completion of executables either in a user's path or a given path :param text: the string prefix we are attempting to match (all matches must begin with it) :param line: the current input line with leading whitespace removed :param begidx: the beginning index of the prefix text :param endidx: the ending index of the prefix text :param complete_blank: If True, then a blank will complete all shell commands in a user's path. If False, then no completion is performed. Defaults to False to match Bash shell behavior. :return: a list of possible tab completions """ # Don't tab complete anything if no shell command has been started if not complete_blank and not text: return [] # If there are no path characters in the search text, then do shell command completion in the user's path if not text.startswith('~') and os.path.sep not in text: return utils.get_exes_in_path(text) # Otherwise look for executables in the given path else: return self.path_complete( text, line, begidx, endidx, path_filter=lambda path: os.path.isdir(path) or os.access(path, os.X_OK) ) def _redirect_complete(self, text: str, line: str, begidx: int, endidx: int, compfunc: CompleterFunc) -> List[str]: """Called by complete() as the first tab completion function for all commands It determines if it should tab complete for redirection (|, >, >>) or use the completer function for the current command :param text: the string prefix we are attempting to match (all matches must begin with it) :param line: the current input line with leading whitespace removed :param begidx: the beginning index of the prefix text :param endidx: the ending index of the prefix text :param compfunc: the completer function for the current command this will be called if we aren't completing for redirection :return: a list of possible tab completions """ # Get all tokens through the one being completed. We want the raw tokens # so we can tell if redirection strings are quoted and ignore them. _, raw_tokens = self.tokens_for_completion(line, begidx, endidx) if not raw_tokens: # pragma: no cover return [] # Must at least have the command if len(raw_tokens) > 1: # True when command line contains any redirection tokens has_redirection = False # Keep track of state while examining tokens in_pipe = False in_file_redir = False do_shell_completion = False do_path_completion = False prior_token = None for cur_token in raw_tokens: # Process redirection tokens if cur_token in constants.REDIRECTION_TOKENS: has_redirection = True # Check if we are at a pipe if cur_token == constants.REDIRECTION_PIPE: # Do not complete bad syntax (e.g cmd | |) if prior_token == constants.REDIRECTION_PIPE: return [] in_pipe = True in_file_redir = False # Otherwise this is a file redirection token else: if prior_token in constants.REDIRECTION_TOKENS or in_file_redir: # Do not complete bad syntax (e.g cmd | >) (e.g cmd > blah >) return [] in_pipe = False in_file_redir = True # Only tab complete after redirection tokens if redirection is allowed elif self.allow_redirection: do_shell_completion = False do_path_completion = False if prior_token == constants.REDIRECTION_PIPE: do_shell_completion = True elif in_pipe or prior_token in (constants.REDIRECTION_OUTPUT, constants.REDIRECTION_APPEND): do_path_completion = True prior_token = cur_token if do_shell_completion: return self.shell_cmd_complete(text, line, begidx, endidx) elif do_path_completion: return self.path_complete(text, line, begidx, endidx) # If there were redirection strings anywhere on the command line, then we # are no longer tab completing for the current command elif has_redirection: return [] # Call the command's completer function return compfunc(text, line, begidx, endidx) @staticmethod def _pad_matches_to_display(matches_to_display: List[str]) -> Tuple[List[str], int]: # pragma: no cover """Adds padding to the matches being displayed as tab completion suggestions. The default padding of readline/pyreadine is small and not visually appealing especially if matches have spaces. It appears very squished together. :param matches_to_display: the matches being padded :return: the padded matches and length of padding that was added """ if rl_type == RlType.GNU: # Add 2 to the padding of 2 that readline uses for a total of 4. padding = 2 * ' ' elif rl_type == RlType.PYREADLINE: # Add 3 to the padding of 1 that pyreadline3 uses for a total of 4. padding = 3 * ' ' else: return matches_to_display, 0 return [cur_match + padding for cur_match in matches_to_display], len(padding) def _display_matches_gnu_readline( self, substitution: str, matches: List[str], longest_match_length: int ) -> None: # pragma: no cover """Prints a match list using GNU readline's rl_display_match_list() :param substitution: the substitution written to the command line :param matches: the tab completion matches to display :param longest_match_length: longest printed length of the matches """ if rl_type == RlType.GNU: # Print hint if one exists and we are supposed to display it hint_printed = False if self.always_show_hint and self.completion_hint: hint_printed = True sys.stdout.write('\n' + self.completion_hint) # Check if we already have formatted results to print if self.formatted_completions: if not hint_printed: sys.stdout.write('\n') sys.stdout.write('\n' + self.formatted_completions + '\n\n') # Otherwise use readline's formatter else: # Check if we should show display_matches if self.display_matches: matches_to_display = self.display_matches # Recalculate longest_match_length for display_matches longest_match_length = 0 for cur_match in matches_to_display: cur_length = ansi.style_aware_wcswidth(cur_match) if cur_length > longest_match_length: longest_match_length = cur_length else: matches_to_display = matches # Add padding for visual appeal matches_to_display, padding_length = self._pad_matches_to_display(matches_to_display) longest_match_length += padding_length # We will use readline's display function (rl_display_match_list()), so we # need to encode our string as bytes to place in a C array. encoded_substitution = bytes(substitution, encoding='utf-8') encoded_matches = [bytes(cur_match, encoding='utf-8') for cur_match in matches_to_display] # rl_display_match_list() expects matches to be in argv format where # substitution is the first element, followed by the matches, and then a NULL. strings_array = cast(List[Optional[bytes]], (ctypes.c_char_p * (1 + len(encoded_matches) + 1))()) # Copy in the encoded strings and add a NULL to the end strings_array[0] = encoded_substitution strings_array[1:-1] = encoded_matches strings_array[-1] = None # rl_display_match_list(strings_array, number of completion matches, longest match length) readline_lib.rl_display_match_list(strings_array, len(encoded_matches), longest_match_length) # Redraw prompt and input line rl_force_redisplay() def _display_matches_pyreadline(self, matches: List[str]) -> None: # pragma: no cover """Prints a match list using pyreadline3's _display_completions() :param matches: the tab completion matches to display """ if rl_type == RlType.PYREADLINE: # Print hint if one exists and we are supposed to display it hint_printed = False if self.always_show_hint and self.completion_hint: hint_printed = True readline.rl.mode.console.write('\n' + self.completion_hint) # Check if we already have formatted results to print if self.formatted_completions: if not hint_printed: readline.rl.mode.console.write('\n') readline.rl.mode.console.write('\n' + self.formatted_completions + '\n\n') # Redraw the prompt and input lines rl_force_redisplay() # Otherwise use pyreadline3's formatter else: # Check if we should show display_matches if self.display_matches: matches_to_display = self.display_matches else: matches_to_display = matches # Add padding for visual appeal matches_to_display, _ = self._pad_matches_to_display(matches_to_display) # Display matches using actual display function. This also redraws the prompt and input lines. orig_pyreadline_display(matches_to_display) @staticmethod def _determine_ap_completer_type(parser: argparse.ArgumentParser) -> Type[argparse_completer.ArgparseCompleter]: """ Determine what type of ArgparseCompleter to use on a given parser. If the parser does not have one set, then use argparse_completer.DEFAULT_AP_COMPLETER. :param parser: the parser to examine :return: type of ArgparseCompleter """ Completer = Optional[Type[argparse_completer.ArgparseCompleter]] completer_type: Completer = parser.get_ap_completer_type() # type: ignore[attr-defined] if completer_type is None: completer_type = argparse_completer.DEFAULT_AP_COMPLETER return completer_type def _perform_completion( self, text: str, line: str, begidx: int, endidx: int, custom_settings: Optional[utils.CustomCompletionSettings] = None ) -> None: """ Helper function for complete() that performs the actual completion :param text: the string prefix we are attempting to match (all matches must begin with it) :param line: the current input line with leading whitespace removed :param begidx: the beginning index of the prefix text :param endidx: the ending index of the prefix text :param custom_settings: optional prepopulated completion settings """ # If custom_settings is None, then we are completing a command's argument. # Parse the command line to get the command token. command = '' if custom_settings is None: statement = self.statement_parser.parse_command_only(line) command = statement.command # Malformed command line (e.g. quoted command token) if not command: return expanded_line = statement.command_and_args if not expanded_line[-1:].isspace(): # Unquoted trailing whitespace gets stripped by parse_command_only(). # Restore it since line is only supposed to be lstripped when passed # to completer functions according to the Python cmd docs. Regardless # of what type of whitespace (' ', \n) was stripped, just append spaces # since shlex treats whitespace characters the same when splitting. rstripped_len = len(line) - len(line.rstrip()) expanded_line += ' ' * rstripped_len # Fix the index values if expanded_line has a different size than line if len(expanded_line) != len(line): diff = len(expanded_line) - len(line) begidx += diff endidx += diff # Overwrite line to pass into completers line = expanded_line # Get all tokens through the one being completed tokens, raw_tokens = self.tokens_for_completion(line, begidx, endidx) if not tokens: # pragma: no cover return # Determine the completer function to use for the command's argument if custom_settings is None: # Check if a macro was entered if command in self.macros: completer_func = self.path_complete # Check if a command was entered elif command in self.get_all_commands(): # Get the completer function for this command func_attr = getattr(self, constants.COMPLETER_FUNC_PREFIX + command, None) if func_attr is not None: completer_func = func_attr else: # There's no completer function, next see if the command uses argparse func = self.cmd_func(command) argparser = None if func is None else self._command_parsers.get(func) if func is not None and argparser is not None: # Get arguments for complete() preserve_quotes = getattr(func, constants.CMD_ATTR_PRESERVE_QUOTES) cmd_set = self.find_commandset_for_command(command) # Create the argparse completer completer_type = self._determine_ap_completer_type(argparser) completer = completer_type(argparser, self) completer_func = functools.partial( completer.complete, tokens=raw_tokens[1:] if preserve_quotes else tokens[1:], cmd_set=cmd_set ) else: completer_func = self.completedefault # type: ignore[assignment] # Not a recognized macro or command else: # Check if this command should be run as a shell command if self.default_to_shell and command in utils.get_exes_in_path(command): completer_func = self.path_complete else: completer_func = self.completedefault # type: ignore[assignment] # Otherwise we are completing the command token or performing custom completion else: # Create the argparse completer completer_type = self._determine_ap_completer_type(custom_settings.parser) completer = completer_type(custom_settings.parser, self) completer_func = functools.partial( completer.complete, tokens=raw_tokens if custom_settings.preserve_quotes else tokens, cmd_set=None ) # Text we need to remove from completions later text_to_remove = '' # Get the token being completed with any opening quote preserved raw_completion_token = raw_tokens[-1] # Used for adding quotes to the completion token completion_token_quote = '' # Check if the token being completed has an opening quote if raw_completion_token and raw_completion_token[0] in constants.QUOTES: # Since the token is still being completed, we know the opening quote is unclosed. # Save the quote so we can add a matching closing quote later. completion_token_quote = raw_completion_token[0] # readline still performs word breaks after a quote. Therefore, something like quoted search # text with a space would have resulted in begidx pointing to the middle of the token we # we want to complete. Figure out where that token actually begins and save the beginning # portion of it that was not part of the text readline gave us. We will remove it from the # completions later since readline expects them to start with the original text. actual_begidx = line[:endidx].rfind(tokens[-1]) if actual_begidx != begidx: text_to_remove = line[actual_begidx:begidx] # Adjust text and where it begins so the completer routines # get unbroken search text to complete on. text = text_to_remove + text begidx = actual_begidx # Attempt tab completion for redirection first, and if that isn't occurring, # call the completer function for the current command self.completion_matches = self._redirect_complete(text, line, begidx, endidx, completer_func) if self.completion_matches: # Eliminate duplicates self.completion_matches = utils.remove_duplicates(self.completion_matches) self.display_matches = utils.remove_duplicates(self.display_matches) if not self.display_matches: # Since self.display_matches is empty, set it to self.completion_matches # before we alter them. That way the suggestions will reflect how we parsed # the token being completed and not how readline did. import copy self.display_matches = copy.copy(self.completion_matches) # Check if we need to add an opening quote if not completion_token_quote: add_quote = False # This is the tab completion text that will appear on the command line. common_prefix = os.path.commonprefix(self.completion_matches) if self.matches_delimited: # Check if any portion of the display matches appears in the tab completion display_prefix = os.path.commonprefix(self.display_matches) # For delimited matches, we check for a space in what appears before the display # matches (common_prefix) as well as in the display matches themselves. if ' ' in common_prefix or (display_prefix and any(' ' in match for match in self.display_matches)): add_quote = True # If there is a tab completion and any match has a space, then add an opening quote elif common_prefix and any(' ' in match for match in self.completion_matches): add_quote = True if add_quote: # Figure out what kind of quote to add and save it as the unclosed_quote if any('"' in match for match in self.completion_matches): completion_token_quote = "'" else: completion_token_quote = '"' self.completion_matches = [completion_token_quote + match for match in self.completion_matches] # Check if we need to remove text from the beginning of tab completions elif text_to_remove: self.completion_matches = [match.replace(text_to_remove, '', 1) for match in self.completion_matches] # If we have one result, then add a closing quote if needed and allowed if len(self.completion_matches) == 1 and self.allow_closing_quote and completion_token_quote: self.completion_matches[0] += completion_token_quote def complete( # type: ignore[override] self, text: str, state: int, custom_settings: Optional[utils.CustomCompletionSettings] = None ) -> Optional[str]: """Override of cmd's complete method which returns the next possible completion for 'text' This completer function is called by readline as complete(text, state), for state in 0, 1, 2, …, until it returns a non-string value. It should return the next possible completion starting with text. Since readline suppresses any exception raised in completer functions, they can be difficult to debug. Therefore, this function wraps the actual tab completion logic and prints to stderr any exception that occurs before returning control to readline. :param text: the current word that user is typing :param state: non-negative integer :param custom_settings: used when not tab completing the main command line :return: the next possible completion for text or None """ try: if state == 0: self._reset_completion_defaults() # Check if we are completing a multiline command if self._at_continuation_prompt: # lstrip and prepend the previously typed portion of this multiline command lstripped_previous = self._multiline_in_progress.lstrip() line = lstripped_previous + readline.get_line_buffer() # Increment the indexes to account for the prepended text begidx = len(lstripped_previous) + readline.get_begidx() endidx = len(lstripped_previous) + readline.get_endidx() else: # lstrip the original line orig_line = readline.get_line_buffer() line = orig_line.lstrip() num_stripped = len(orig_line) - len(line) # Calculate new indexes for the stripped line. If the cursor is at a position before the end of a # line of spaces, then the following math could result in negative indexes. Enforce a max of 0. begidx = max(readline.get_begidx() - num_stripped, 0) endidx = max(readline.get_endidx() - num_stripped, 0) # Shortcuts are not word break characters when tab completing. Therefore, shortcuts become part # of the text variable if there isn't a word break, like a space, after it. We need to remove it # from text and update the indexes. This only applies if we are at the beginning of the command line. shortcut_to_restore = '' if begidx == 0 and custom_settings is None: for shortcut, _ in self.statement_parser.shortcuts: if text.startswith(shortcut): # Save the shortcut to restore later shortcut_to_restore = shortcut # Adjust text and where it begins text = text[len(shortcut_to_restore) :] begidx += len(shortcut_to_restore) break else: # No shortcut was found. Complete the command token. parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(add_help=False) parser.add_argument( 'command', metavar="COMMAND", help="command, alias, or macro name", choices=self._get_commands_aliases_and_macros_for_completion(), ) custom_settings = utils.CustomCompletionSettings(parser) self._perform_completion(text, line, begidx, endidx, custom_settings) # Check if we need to restore a shortcut in the tab completions # so it doesn't get erased from the command line if shortcut_to_restore: self.completion_matches = [shortcut_to_restore + match for match in self.completion_matches] # If we have one result and we are at the end of the line, then add a space if allowed if len(self.completion_matches) == 1 and endidx == len(line) and self.allow_appended_space: self.completion_matches[0] += ' ' # Sort matches if they haven't already been sorted if not self.matches_sorted: self.completion_matches.sort(key=self.default_sort_key) self.display_matches.sort(key=self.default_sort_key) self.matches_sorted = True try: return self.completion_matches[state] except IndexError: return None except CompletionError as ex: # Don't print error and redraw the prompt unless the error has length err_str = str(ex) if err_str: if ex.apply_style: err_str = ansi.style_error(err_str) ansi.style_aware_write(sys.stdout, '\n' + err_str + '\n') rl_force_redisplay() return None except Exception as ex: # Insert a newline so the exception doesn't print in the middle of the command line being tab completed self.perror() self.pexcept(ex) rl_force_redisplay() return None def in_script(self) -> bool: """Return whether a text script is running""" return self._current_script_dir is not None def in_pyscript(self) -> bool: """Return whether running inside a Python shell or pyscript""" return self._in_py @property def aliases(self) -> Dict[str, str]: """Read-only property to access the aliases stored in the StatementParser""" return self.statement_parser.aliases def get_names(self) -> List[str]: """Return an alphabetized list of names comprising the attributes of the cmd2 class instance.""" return dir(self) def get_all_commands(self) -> List[str]: """Return a list of all commands""" return [ name[len(constants.COMMAND_FUNC_PREFIX) :] for name in self.get_names() if name.startswith(constants.COMMAND_FUNC_PREFIX) and callable(getattr(self, name)) ] def get_visible_commands(self) -> List[str]: """Return a list of commands that have not been hidden or disabled""" return [ command for command in self.get_all_commands() if command not in self.hidden_commands and command not in self.disabled_commands ] # Table displayed when tab completing aliases _alias_completion_table = SimpleTable([Column('Value', width=80)], divider_char=None) def _get_alias_completion_items(self) -> List[CompletionItem]: """Return list of alias names and values as CompletionItems""" results: List[CompletionItem] = [] for cur_key in self.aliases: row_data = [self.aliases[cur_key]] results.append(CompletionItem(cur_key, self._alias_completion_table.generate_data_row(row_data))) return results # Table displayed when tab completing macros _macro_completion_table = SimpleTable([Column('Value', width=80)], divider_char=None) def _get_macro_completion_items(self) -> List[CompletionItem]: """Return list of macro names and values as CompletionItems""" results: List[CompletionItem] = [] for cur_key in self.macros: row_data = [self.macros[cur_key].value] results.append(CompletionItem(cur_key, self._macro_completion_table.generate_data_row(row_data))) return results # Table displayed when tab completing Settables _settable_completion_table = SimpleTable([Column('Value', width=30), Column('Description', width=60)], divider_char=None) def _get_settable_completion_items(self) -> List[CompletionItem]: """Return list of Settable names, values, and descriptions as CompletionItems""" results: List[CompletionItem] = [] for cur_key in self.settables: row_data = [self.settables[cur_key].get_value(), self.settables[cur_key].description] results.append(CompletionItem(cur_key, self._settable_completion_table.generate_data_row(row_data))) return results def _get_commands_aliases_and_macros_for_completion(self) -> List[str]: """Return a list of visible commands, aliases, and macros for tab completion""" visible_commands = set(self.get_visible_commands()) alias_names = set(self.aliases) macro_names = set(self.macros) return list(visible_commands | alias_names | macro_names) def get_help_topics(self) -> List[str]: """Return a list of help topics""" all_topics = [ name[len(constants.HELP_FUNC_PREFIX) :] for name in self.get_names() if name.startswith(constants.HELP_FUNC_PREFIX) and callable(getattr(self, name)) ] # Filter out hidden and disabled commands return [topic for topic in all_topics if topic not in self.hidden_commands and topic not in self.disabled_commands] def sigint_handler(self, signum: int, _: Optional[FrameType]) -> None: """Signal handler for SIGINTs which typically come from Ctrl-C events. If you need custom SIGINT behavior, then override this method. :param signum: signal number :param _: the current stack frame or None """ if self._cur_pipe_proc_reader is not None: # Pass the SIGINT to the current pipe process self._cur_pipe_proc_reader.send_sigint() # Check if we are allowed to re-raise the KeyboardInterrupt if not self.sigint_protection: raise_interrupt = True if self.current_command is not None: command_set = self.find_commandset_for_command(self.current_command.command) if command_set is not None: raise_interrupt = not command_set.sigint_handler() if raise_interrupt: self._raise_keyboard_interrupt() def termination_signal_handler(self, signum: int, _: Optional[FrameType]) -> None: """ Signal handler for SIGHUP and SIGTERM. Only runs on Linux and Mac. SIGHUP - received when terminal window is closed SIGTERM - received when this app has been requested to terminate The basic purpose of this method is to call sys.exit() so our exit handler will run and save the persistent history file. If you need more complex behavior like killing threads and performing cleanup, then override this method. :param signum: signal number :param _: the current stack frame or None """ # POSIX systems add 128 to signal numbers for the exit code sys.exit(128 + signum) def _raise_keyboard_interrupt(self) -> None: """Helper function to raise a KeyboardInterrupt""" raise KeyboardInterrupt("Got a keyboard interrupt") def precmd(self, statement: Union[Statement, str]) -> Statement: """Hook method executed just before the command is executed by :meth:`~cmd2.Cmd.onecmd` and after adding it to history. :param statement: subclass of str which also contains the parsed input :return: a potentially modified version of the input Statement object See :meth:`~cmd2.Cmd.register_postparsing_hook` and :meth:`~cmd2.Cmd.register_precmd_hook` for more robust ways to run hooks before the command is executed. See :ref:`features/hooks:Postparsing Hooks` and :ref:`features/hooks:Precommand Hooks` for more information. """ return Statement(statement) if not isinstance(statement, Statement) else statement def postcmd(self, stop: bool, statement: Union[Statement, str]) -> bool: """Hook method executed just after a command is executed by :meth:`~cmd2.Cmd.onecmd`. :param stop: return `True` to request the command loop terminate :param statement: subclass of str which also contains the parsed input See :meth:`~cmd2.Cmd.register_postcmd_hook` and :meth:`~cmd2.Cmd.register_cmdfinalization_hook` for more robust ways to run hooks after the command is executed. See :ref:`features/hooks:Postcommand Hooks` and :ref:`features/hooks:Command Finalization Hooks` for more information. """ return stop def preloop(self) -> None: """Hook method executed once when the :meth:`~.cmd2.Cmd.cmdloop()` method is called. See :meth:`~cmd2.Cmd.register_preloop_hook` for a more robust way to run hooks before the command loop begins. See :ref:`features/hooks:Application Lifecycle Hooks` for more information. """ pass def postloop(self) -> None: """Hook method executed once when the :meth:`~.cmd2.Cmd.cmdloop()` method is about to return. See :meth:`~cmd2.Cmd.register_postloop_hook` for a more robust way to run hooks after the command loop completes. See :ref:`features/hooks:Application Lifecycle Hooks` for more information. """ pass def parseline(self, line: str) -> Tuple[str, str, str]: """Parse the line into a command name and a string containing the arguments. NOTE: This is an override of a parent class method. It is only used by other parent class methods. Different from the parent class method, this ignores self.identchars. :param line: line read by readline :return: tuple containing (command, args, line) """ statement = self.statement_parser.parse_command_only(line) return statement.command, statement.args, statement.command_and_args def onecmd_plus_hooks( self, line: str, *, add_to_history: bool = True, raise_keyboard_interrupt: bool = False, py_bridge_call: bool = False, orig_rl_history_length: Optional[int] = None, ) -> bool: """Top-level function called by cmdloop() to handle parsing a line and running the command and all of its hooks. :param line: command line to run :param add_to_history: If True, then add this command to history. Defaults to True. :param raise_keyboard_interrupt: if True, then KeyboardInterrupt exceptions will be raised if stop isn't already True. This is used when running commands in a loop to be able to stop the whole loop and not just the current command. Defaults to False. :param py_bridge_call: This should only ever be set to True by PyBridge to signify the beginning of an app() call from Python. It is used to enable/disable the storage of the command's stdout. :param orig_rl_history_length: Optional length of the readline history before the current command was typed. This is used to assist in combining multiline readline history entries and is only populated by cmd2. Defaults to None. :return: True if running of commands should stop """ import datetime stop = False statement = None try: # Convert the line into a Statement statement = self._input_line_to_statement(line, orig_rl_history_length=orig_rl_history_length) # call the postparsing hooks postparsing_data = plugin.PostparsingData(False, statement) for postparsing_func in self._postparsing_hooks: postparsing_data = postparsing_func(postparsing_data) if postparsing_data.stop: break # unpack the postparsing_data object statement = postparsing_data.statement stop = postparsing_data.stop if stop: # we should not run the command, but # we need to run the finalization hooks raise EmptyStatement redir_saved_state: Optional[utils.RedirectionSavedState] = None try: # Get sigint protection while we set up redirection with self.sigint_protection: if py_bridge_call: # Start saving command's stdout at this point self.stdout.pause_storage = False # type: ignore[attr-defined] redir_saved_state = self._redirect_output(statement) timestart = datetime.datetime.now() # precommand hooks precmd_data = plugin.PrecommandData(statement) for precmd_func in self._precmd_hooks: precmd_data = precmd_func(precmd_data) statement = precmd_data.statement # call precmd() for compatibility with cmd.Cmd statement = self.precmd(statement) # go run the command function stop = self.onecmd(statement, add_to_history=add_to_history) # postcommand hooks postcmd_data = plugin.PostcommandData(stop, statement) for postcmd_func in self._postcmd_hooks: postcmd_data = postcmd_func(postcmd_data) # retrieve the final value of stop, ignoring any statement modification from the hooks stop = postcmd_data.stop # call postcmd() for compatibility with cmd.Cmd stop = self.postcmd(stop, statement) if self.timing: self.pfeedback(f'Elapsed: {datetime.datetime.now() - timestart}') finally: # Get sigint protection while we restore stuff with self.sigint_protection: if redir_saved_state is not None: self._restore_output(statement, redir_saved_state) if py_bridge_call: # Stop saving command's stdout before command finalization hooks run self.stdout.pause_storage = True # type: ignore[attr-defined] except (SkipPostcommandHooks, EmptyStatement): # Don't do anything, but do allow command finalization hooks to run pass except Cmd2ShlexError as ex: self.perror(f"Invalid syntax: {ex}") except RedirectionError as ex: self.perror(ex) except KeyboardInterrupt as ex: if raise_keyboard_interrupt and not stop: raise ex except SystemExit as ex: if isinstance(ex.code, int): self.exit_code = ex.code stop = True except PassThroughException as ex: raise ex.wrapped_ex except Exception as ex: self.pexcept(ex) finally: try: stop = self._run_cmdfinalization_hooks(stop, statement) except KeyboardInterrupt as ex: if raise_keyboard_interrupt and not stop: raise ex except SystemExit as ex: if isinstance(ex.code, int): self.exit_code = ex.code stop = True except PassThroughException as ex: raise ex.wrapped_ex except Exception as ex: self.pexcept(ex) return stop def _run_cmdfinalization_hooks(self, stop: bool, statement: Optional[Statement]) -> bool: """Run the command finalization hooks""" with self.sigint_protection: if not sys.platform.startswith('win') and self.stdin.isatty(): # Before the next command runs, fix any terminal problems like those # caused by certain binary characters having been printed to it. import subprocess proc = subprocess.Popen(['stty', 'sane']) proc.communicate() data = plugin.CommandFinalizationData(stop, statement) for func in self._cmdfinalization_hooks: data = func(data) # retrieve the final value of stop, ignoring any # modifications to the statement return data.stop def runcmds_plus_hooks( self, cmds: Union[List[HistoryItem], List[str]], *, add_to_history: bool = True, stop_on_keyboard_interrupt: bool = False, ) -> bool: """ Used when commands are being run in an automated fashion like text scripts or history replays. The prompt and command line for each command will be printed if echo is True. :param cmds: commands to run :param add_to_history: If True, then add these commands to history. Defaults to True. :param stop_on_keyboard_interrupt: if True, then stop running contents of cmds if Ctrl-C is pressed instead of moving to the next command in the list. This is used when the commands are part of a group, like a text script, which should stop upon Ctrl-C. Defaults to False. :return: True if running of commands should stop """ for line in cmds: if isinstance(line, HistoryItem): line = line.raw if self.echo: self.poutput(f'{self.prompt}{line}') try: if self.onecmd_plus_hooks( line, add_to_history=add_to_history, raise_keyboard_interrupt=stop_on_keyboard_interrupt ): return True except KeyboardInterrupt as ex: if stop_on_keyboard_interrupt: self.perror(ex) break return False def _complete_statement(self, line: str, *, orig_rl_history_length: Optional[int] = None) -> Statement: """Keep accepting lines of input until the command is complete. There is some pretty hacky code here to handle some quirks of self._read_command_line(). It returns a literal 'eof' if the input pipe runs out. We can't refactor it because we need to retain backwards compatibility with the standard library version of cmd. :param line: the line being parsed :param orig_rl_history_length: Optional length of the readline history before the current command was typed. This is used to assist in combining multiline readline history entries and is only populated by cmd2. Defaults to None. :return: the completed Statement :raises: Cmd2ShlexError if a shlex error occurs (e.g. No closing quotation) :raises: EmptyStatement when the resulting Statement is blank """ def combine_rl_history(statement: Statement) -> None: """Combine all lines of a multiline command into a single readline history entry""" if orig_rl_history_length is None or not statement.multiline_command: return # Remove all previous lines added to history for this command while readline.get_current_history_length() > orig_rl_history_length: readline.remove_history_item(readline.get_current_history_length() - 1) formatted_command = single_line_format(statement) # If formatted command is different than the previous history item, add it if orig_rl_history_length == 0 or formatted_command != readline.get_history_item(orig_rl_history_length): readline.add_history(formatted_command) while True: try: statement = self.statement_parser.parse(line) if statement.multiline_command and statement.terminator: # we have a completed multiline command, we are done break if not statement.multiline_command: # it's not a multiline command, but we parsed it ok # so we are done break except Cmd2ShlexError: # we have an unclosed quotation mark, let's parse only the command # and see if it's a multiline statement = self.statement_parser.parse_command_only(line) if not statement.multiline_command: # not a multiline command, so raise the exception raise # if we get here we must have: # - a multiline command with no terminator # - a multiline command with unclosed quotation marks try: self._at_continuation_prompt = True # Save the command line up to this point for tab completion self._multiline_in_progress = line + '\n' # Get next line of this command nextline = self._read_command_line(self.continuation_prompt) if nextline == 'eof': # they entered either a blank line, or we hit an EOF # for some other reason. Turn the literal 'eof' # into a blank line, which serves as a command # terminator nextline = '\n' self.poutput(nextline) line += f'\n{nextline}' # Combine all history lines of this multiline command as we go. if nextline: statement = self.statement_parser.parse_command_only(line) combine_rl_history(statement) except KeyboardInterrupt: self.poutput('^C') statement = self.statement_parser.parse('') break finally: self._at_continuation_prompt = False if not statement.command: raise EmptyStatement else: # If necessary, update history with completed multiline command. combine_rl_history(statement) return statement def _input_line_to_statement(self, line: str, *, orig_rl_history_length: Optional[int] = None) -> Statement: """ Parse the user's input line and convert it to a Statement, ensuring that all macros are also resolved :param line: the line being parsed :param orig_rl_history_length: Optional length of the readline history before the current command was typed. This is used to assist in combining multiline readline history entries and is only populated by cmd2. Defaults to None. :return: parsed command line as a Statement :raises: Cmd2ShlexError if a shlex error occurs (e.g. No closing quotation) :raises: EmptyStatement when the resulting Statement is blank """ used_macros = [] orig_line = None # Continue until all macros are resolved while True: # Make sure all input has been read and convert it to a Statement statement = self._complete_statement(line, orig_rl_history_length=orig_rl_history_length) # If this is the first loop iteration, save the original line and stop # combining multiline history entries in the remaining iterations. if orig_line is None: orig_line = statement.raw orig_rl_history_length = None # Check if this command matches a macro and wasn't already processed to avoid an infinite loop if statement.command in self.macros.keys() and statement.command not in used_macros: used_macros.append(statement.command) resolve_result = self._resolve_macro(statement) if resolve_result is None: raise EmptyStatement line = resolve_result else: break # This will be true when a macro was used if orig_line != statement.raw: # Build a Statement that contains the resolved macro line # but the originally typed line for its raw member. statement = Statement( statement.args, raw=orig_line, command=statement.command, arg_list=statement.arg_list, multiline_command=statement.multiline_command, terminator=statement.terminator, suffix=statement.suffix, pipe_to=statement.pipe_to, output=statement.output, output_to=statement.output_to, ) return statement def _resolve_macro(self, statement: Statement) -> Optional[str]: """ Resolve a macro and return the resulting string :param statement: the parsed statement from the command line :return: the resolved macro or None on error """ if statement.command not in self.macros.keys(): raise KeyError(f"{statement.command} is not a macro") macro = self.macros[statement.command] # Make sure enough arguments were passed in if len(statement.arg_list) < macro.minimum_arg_count: plural = '' if macro.minimum_arg_count == 1 else 's' self.perror(f"The macro '{statement.command}' expects at least {macro.minimum_arg_count} argument{plural}") return None # Resolve the arguments in reverse and read their values from statement.argv since those # are unquoted. Macro args should have been quoted when the macro was created. resolved = macro.value reverse_arg_list = sorted(macro.arg_list, key=lambda ma: ma.start_index, reverse=True) for macro_arg in reverse_arg_list: if macro_arg.is_escaped: to_replace = '{{' + macro_arg.number_str + '}}' replacement = '{' + macro_arg.number_str + '}' else: to_replace = '{' + macro_arg.number_str + '}' replacement = statement.argv[int(macro_arg.number_str)] parts = resolved.rsplit(to_replace, maxsplit=1) resolved = parts[0] + replacement + parts[1] # Append extra arguments and use statement.arg_list since these arguments need their quotes preserved for stmt_arg in statement.arg_list[macro.minimum_arg_count :]: resolved += ' ' + stmt_arg # Restore any terminator, suffix, redirection, etc. return resolved + statement.post_command def _redirect_output(self, statement: Statement) -> utils.RedirectionSavedState: """Set up a command's output redirection for >, >>, and |. :param statement: a parsed statement from the user :return: A bool telling if an error occurred and a utils.RedirectionSavedState object :raises: RedirectionError if an error occurs trying to pipe or redirect """ import io import subprocess # Initialize the redirection saved state redir_saved_state = utils.RedirectionSavedState( cast(TextIO, self.stdout), sys.stdout, self._cur_pipe_proc_reader, self._redirecting ) # The ProcReader for this command cmd_pipe_proc_reader: Optional[utils.ProcReader] = None if not self.allow_redirection: # Don't return since we set some state variables at the end of the function pass elif statement.pipe_to: # Create a pipe with read and write sides read_fd, write_fd = os.pipe() # Open each side of the pipe subproc_stdin = io.open(read_fd, 'r') new_stdout: TextIO = cast(TextIO, io.open(write_fd, 'w')) # Create pipe process in a separate group to isolate our signals from it. If a Ctrl-C event occurs, # our sigint handler will forward it only to the most recent pipe process. This makes sure pipe # processes close in the right order (most recent first). kwargs: Dict[str, Any] = dict() if sys.platform == 'win32': kwargs['creationflags'] = subprocess.CREATE_NEW_PROCESS_GROUP else: kwargs['start_new_session'] = True # Attempt to run the pipe process in the user's preferred shell instead of the default behavior of using sh. shell = os.environ.get("SHELL") if shell: kwargs['executable'] = shell # For any stream that is a StdSim, we will use a pipe so we can capture its output proc = subprocess.Popen( # type: ignore[call-overload] statement.pipe_to, stdin=subproc_stdin, stdout=subprocess.PIPE if isinstance(self.stdout, utils.StdSim) else self.stdout, # type: ignore[unreachable] stderr=subprocess.PIPE if isinstance(sys.stderr, utils.StdSim) else sys.stderr, # type: ignore[unreachable] shell=True, **kwargs, ) # Popen was called with shell=True so the user can chain pipe commands and redirect their output # like: !ls -l | grep user | wc -l > out.txt. But this makes it difficult to know if the pipe process # started OK, since the shell itself always starts. Therefore, we will wait a short time and check # if the pipe process is still running. try: proc.wait(0.2) except subprocess.TimeoutExpired: pass # Check if the pipe process already exited if proc.returncode is not None: subproc_stdin.close() new_stdout.close() raise RedirectionError(f'Pipe process exited with code {proc.returncode} before command could run') else: redir_saved_state.redirecting = True # type: ignore[unreachable] cmd_pipe_proc_reader = utils.ProcReader(proc, cast(TextIO, self.stdout), sys.stderr) sys.stdout = self.stdout = new_stdout elif statement.output: if statement.output_to: # redirecting to a file # statement.output can only contain REDIRECTION_APPEND or REDIRECTION_OUTPUT mode = 'a' if statement.output == constants.REDIRECTION_APPEND else 'w' try: # Use line buffering new_stdout = cast(TextIO, open(utils.strip_quotes(statement.output_to), mode=mode, buffering=1)) except OSError as ex: raise RedirectionError(f'Failed to redirect because: {ex}') redir_saved_state.redirecting = True sys.stdout = self.stdout = new_stdout else: # Redirecting to a paste buffer # we are going to direct output to a temporary file, then read it back in and # put it in the paste buffer later if not self.allow_clipboard: raise RedirectionError("Clipboard access not allowed") # attempt to get the paste buffer, this forces pyperclip to go figure # out if it can actually interact with the paste buffer, and will throw exceptions # if it's not gonna work. That way we throw the exception before we go # run the command and queue up all the output. if this is going to fail, # no point opening up the temporary file current_paste_buffer = get_paste_buffer() # create a temporary file to store output new_stdout = cast(TextIO, tempfile.TemporaryFile(mode="w+")) redir_saved_state.redirecting = True sys.stdout = self.stdout = new_stdout if statement.output == constants.REDIRECTION_APPEND: self.stdout.write(current_paste_buffer) self.stdout.flush() # These are updated regardless of whether the command redirected self._cur_pipe_proc_reader = cmd_pipe_proc_reader self._redirecting = redir_saved_state.redirecting return redir_saved_state def _restore_output(self, statement: Statement, saved_redir_state: utils.RedirectionSavedState) -> None: """Handles restoring state after output redirection :param statement: Statement object which contains the parsed input from the user :param saved_redir_state: contains information needed to restore state data """ if saved_redir_state.redirecting: # If we redirected output to the clipboard if statement.output and not statement.output_to: self.stdout.seek(0) write_to_paste_buffer(self.stdout.read()) try: # Close the file or pipe that stdout was redirected to self.stdout.close() except BrokenPipeError: pass # Restore the stdout values self.stdout = cast(TextIO, saved_redir_state.saved_self_stdout) sys.stdout = cast(TextIO, saved_redir_state.saved_sys_stdout) # Check if we need to wait for the process being piped to if self._cur_pipe_proc_reader is not None: self._cur_pipe_proc_reader.wait() # These are restored regardless of whether the command redirected self._cur_pipe_proc_reader = saved_redir_state.saved_pipe_proc_reader self._redirecting = saved_redir_state.saved_redirecting def cmd_func(self, command: str) -> Optional[CommandFunc]: """ Get the function for a command :param command: the name of the command :Example: >>> helpfunc = self.cmd_func('help') helpfunc now contains a reference to the ``do_help`` method """ func_name = constants.COMMAND_FUNC_PREFIX + command func = getattr(self, func_name, None) return cast(CommandFunc, func) if callable(func) else None def onecmd(self, statement: Union[Statement, str], *, add_to_history: bool = True) -> bool: """This executes the actual do_* method for a command. If the command provided doesn't exist, then it executes default() instead. :param statement: intended to be a Statement instance parsed command from the input stream, alternative acceptance of a str is present only for backward compatibility with cmd :param add_to_history: If True, then add this command to history. Defaults to True. :return: a flag indicating whether the interpretation of commands should stop """ # For backwards compatibility with cmd, allow a str to be passed in if not isinstance(statement, Statement): statement = self._input_line_to_statement(statement) func = self.cmd_func(statement.command) if func: # Check to see if this command should be stored in history if ( statement.command not in self.exclude_from_history and statement.command not in self.disabled_commands and add_to_history ): self.history.append(statement) try: self.current_command = statement stop = func(statement) finally: self.current_command = None else: stop = self.default(statement) return stop if stop is not None else False def default(self, statement: Statement) -> Optional[bool]: # type: ignore[override] """Executed when the command given isn't a recognized command implemented by a do_* method. :param statement: Statement object with parsed input """ if self.default_to_shell: if 'shell' not in self.exclude_from_history: self.history.append(statement) return self.do_shell(statement.command_and_args) else: err_msg = self.default_error.format(statement.command) if self.suggest_similar_command and (suggested_command := self._suggest_similar_command(statement.command)): err_msg += f"\n{self.default_suggestion_message.format(suggested_command)}" # Set apply_style to False so styles for default_error and default_suggestion_message are not overridden self.perror(err_msg, apply_style=False) return None def _suggest_similar_command(self, command: str) -> Optional[str]: return suggest_similar(command, self.get_visible_commands()) def read_input( self, prompt: str, *, history: Optional[List[str]] = None, completion_mode: utils.CompletionMode = utils.CompletionMode.NONE, preserve_quotes: bool = False, choices: Optional[Iterable[Any]] = None, choices_provider: Optional[ChoicesProviderFunc] = None, completer: Optional[CompleterFunc] = None, parser: Optional[argparse.ArgumentParser] = None, ) -> str: """ Read input from appropriate stdin value. Also supports tab completion and up-arrow history while input is being entered. :param prompt: prompt to display to user :param history: optional list of strings to use for up-arrow history. If completion_mode is CompletionMode.COMMANDS and this is None, then cmd2's command list history will be used. The passed in history will not be edited. It is the caller's responsibility to add the returned input to history if desired. Defaults to None. :param completion_mode: tells what type of tab completion to support. Tab completion only works when self.use_rawinput is True and sys.stdin is a terminal. Defaults to CompletionMode.NONE. The following optional settings apply when completion_mode is CompletionMode.CUSTOM: :param preserve_quotes: if True, then quoted tokens will keep their quotes when processed by ArgparseCompleter. This is helpful in cases when you're tab completing flag-like tokens (e.g. -o, --option) and you don't want them to be treated as argparse flags when quoted. Set this to True if you plan on passing the string to argparse with the tokens still quoted. A maximum of one of these should be provided: :param choices: iterable of accepted values for single argument :param choices_provider: function that provides choices for single argument :param completer: tab completion function that provides choices for single argument :param parser: an argument parser which supports the tab completion of multiple arguments :return: the line read from stdin with all trailing new lines removed :raises: any exceptions raised by input() and stdin.readline() """ readline_configured = False saved_completer: Optional[CompleterFunc] = None saved_history: Optional[List[str]] = None def configure_readline() -> None: """Configure readline tab completion and history""" nonlocal readline_configured nonlocal saved_completer nonlocal saved_history nonlocal parser if readline_configured or rl_type == RlType.NONE: # pragma: no cover return # Configure tab completion if self._completion_supported(): saved_completer = readline.get_completer() # Disable completion if completion_mode == utils.CompletionMode.NONE: def complete_none(text: str, state: int) -> Optional[str]: # pragma: no cover return None complete_func = complete_none # Complete commands elif completion_mode == utils.CompletionMode.COMMANDS: complete_func = self.complete # Set custom completion settings else: if parser is None: parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(add_help=False) parser.add_argument( 'arg', suppress_tab_hint=True, choices=choices, # type: ignore[arg-type] choices_provider=choices_provider, completer=completer, ) custom_settings = utils.CustomCompletionSettings(parser, preserve_quotes=preserve_quotes) complete_func = functools.partial(self.complete, custom_settings=custom_settings) readline.set_completer(complete_func) # Overwrite history if not completing commands or new history was provided if completion_mode != utils.CompletionMode.COMMANDS or history is not None: saved_history = [] for i in range(1, readline.get_current_history_length() + 1): saved_history.append(readline.get_history_item(i)) readline.clear_history() if history is not None: for item in history: readline.add_history(item) readline_configured = True def restore_readline() -> None: """Restore readline tab completion and history""" nonlocal readline_configured if not readline_configured or rl_type == RlType.NONE: # pragma: no cover return if self._completion_supported(): readline.set_completer(saved_completer) if saved_history is not None: readline.clear_history() for item in saved_history: readline.add_history(item) readline_configured = False # Check we are reading from sys.stdin if self.use_rawinput: if sys.stdin.isatty(): try: # Deal with the vagaries of readline and ANSI escape codes escaped_prompt = rl_escape_prompt(prompt) with self.sigint_protection: configure_readline() line = input(escaped_prompt) finally: with self.sigint_protection: restore_readline() else: line = input() if self.echo: sys.stdout.write(f'{prompt}{line}\n') # Otherwise read from self.stdin else: if self.stdin.isatty(): # on a tty, print the prompt first, then read the line self.poutput(prompt, end='') self.stdout.flush() line = self.stdin.readline() if len(line) == 0: line = 'eof' else: # we are reading from a pipe, read the line to see if there is # anything there, if so, then decide whether to print the # prompt or not line = self.stdin.readline() if len(line): # we read something, output the prompt and the something if self.echo: self.poutput(f'{prompt}{line}') else: line = 'eof' return line.rstrip('\r\n') def _read_command_line(self, prompt: str) -> str: """ Read command line from appropriate stdin :param prompt: prompt to display to user :return: command line text of 'eof' if an EOFError was caught :raises: whatever exceptions are raised by input() except for EOFError """ try: # Wrap in try since terminal_lock may not be locked try: # Command line is about to be drawn. Allow asynchronous changes to the terminal. self.terminal_lock.release() except RuntimeError: pass return self.read_input(prompt, completion_mode=utils.CompletionMode.COMMANDS) except EOFError: return 'eof' finally: # Command line is gone. Do not allow asynchronous changes to the terminal. self.terminal_lock.acquire() def _set_up_cmd2_readline(self) -> _SavedReadlineSettings: """ Called at beginning of command loop to set up readline with cmd2-specific settings :return: Class containing saved readline settings """ readline_settings = _SavedReadlineSettings() if rl_type == RlType.GNU: # To calculate line count when printing async_alerts, we rely on commands wider than # the terminal to wrap across multiple lines. The default for horizontal-scroll-mode # is "off" but a user may have overridden it in their readline initialization file. readline.parse_and_bind("set horizontal-scroll-mode off") if self._completion_supported(): # Set up readline for our tab completion needs if rl_type == RlType.GNU: # GNU readline automatically adds a closing quote if the text being completed has an opening quote. # We don't want this behavior since cmd2 only adds a closing quote when self.allow_closing_quote is True. # To fix this behavior, set readline's rl_basic_quote_characters to NULL. We don't need to worry about setting # rl_completion_suppress_quote since we never declared rl_completer_quote_characters. readline_settings.basic_quotes = cast(bytes, ctypes.cast(rl_basic_quote_characters, ctypes.c_void_p).value) rl_basic_quote_characters.value = None readline_settings.completer = readline.get_completer() readline.set_completer(self.complete) # Set the readline word delimiters for completion completer_delims = " \t\n" completer_delims += ''.join(constants.QUOTES) completer_delims += ''.join(constants.REDIRECTION_CHARS) completer_delims += ''.join(self.statement_parser.terminators) readline_settings.delims = readline.get_completer_delims() readline.set_completer_delims(completer_delims) # Enable tab completion readline.parse_and_bind(self.completekey + ": complete") return readline_settings def _restore_readline(self, readline_settings: _SavedReadlineSettings) -> None: """ Called at end of command loop to restore saved readline settings :param readline_settings: the readline settings to restore """ if self._completion_supported(): # Restore what we changed in readline readline.set_completer(readline_settings.completer) readline.set_completer_delims(readline_settings.delims) if rl_type == RlType.GNU: readline.set_completion_display_matches_hook(None) rl_basic_quote_characters.value = readline_settings.basic_quotes elif rl_type == RlType.PYREADLINE: readline.rl.mode._display_completions = orig_pyreadline_display def _cmdloop(self) -> None: """Repeatedly issue a prompt, accept input, parse an initial prefix off the received input, and dispatch to action methods, passing them the remainder of the line as argument. This serves the same role as cmd.cmdloop(). """ saved_readline_settings = None try: # Get sigint protection while we set up readline for cmd2 with self.sigint_protection: saved_readline_settings = self._set_up_cmd2_readline() # Run startup commands stop = self.runcmds_plus_hooks(self._startup_commands) self._startup_commands.clear() while not stop: # Used in building multiline readline history entries. Only applies # when command line is read by input() in a terminal. if rl_type != RlType.NONE and self.use_rawinput and sys.stdin.isatty(): orig_rl_history_length = readline.get_current_history_length() else: orig_rl_history_length = None # Get commands from user try: line = self._read_command_line(self.prompt) except KeyboardInterrupt: self.poutput('^C') line = '' # Run the command along with all associated pre and post hooks stop = self.onecmd_plus_hooks(line, orig_rl_history_length=orig_rl_history_length) finally: # Get sigint protection while we restore readline settings with self.sigint_protection: if saved_readline_settings is not None: self._restore_readline(saved_readline_settings) ############################################################# # Parsers and functions for alias command and subcommands ############################################################# # Top-level parser for alias alias_description = "Manage aliases\n" "\n" "An alias is a command that enables replacement of a word by another string." alias_epilog = "See also:\n" " macro" alias_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description=alias_description, epilog=alias_epilog) alias_parser.add_subparsers(metavar='SUBCOMMAND', required=True) # Preserve quotes since we are passing strings to other commands @with_argparser(alias_parser, preserve_quotes=True) def do_alias(self, args: argparse.Namespace) -> None: """Manage aliases""" # Call handler for whatever subcommand was selected handler = args.cmd2_handler.get() handler(args) # alias -> create alias_create_description = "Create or overwrite an alias" alias_create_epilog = ( "Notes:\n" " If you want to use redirection, pipes, or terminators in the value of the\n" " alias, then quote them.\n" "\n" " Since aliases are resolved during parsing, tab completion will function as\n" " it would for the actual command the alias resolves to.\n" "\n" "Examples:\n" " alias create ls !ls -lF\n" " alias create show_log !cat \"log file.txt\"\n" " alias create save_results print_results \">\" out.txt\n" ) alias_create_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER( description=alias_create_description, epilog=alias_create_epilog ) alias_create_parser.add_argument('name', help='name of this alias') alias_create_parser.add_argument( 'command', help='what the alias resolves to', choices_provider=_get_commands_aliases_and_macros_for_completion ) alias_create_parser.add_argument( 'command_args', nargs=argparse.REMAINDER, help='arguments to pass to command', completer=path_complete ) @as_subcommand_to('alias', 'create', alias_create_parser, help=alias_create_description.lower()) def _alias_create(self, args: argparse.Namespace) -> None: """Create or overwrite an alias""" self.last_result = False # Validate the alias name valid, errmsg = self.statement_parser.is_valid_command(args.name) if not valid: self.perror(f"Invalid alias name: {errmsg}") return if args.name in self.get_all_commands(): self.perror("Alias cannot have the same name as a command") return if args.name in self.macros: self.perror("Alias cannot have the same name as a macro") return # Unquote redirection and terminator tokens tokens_to_unquote = constants.REDIRECTION_TOKENS tokens_to_unquote.extend(self.statement_parser.terminators) utils.unquote_specific_tokens(args.command_args, tokens_to_unquote) # Build the alias value string value = args.command if args.command_args: value += ' ' + ' '.join(args.command_args) # Set the alias result = "overwritten" if args.name in self.aliases else "created" self.poutput(f"Alias '{args.name}' {result}") self.aliases[args.name] = value self.last_result = True # alias -> delete alias_delete_help = "delete aliases" alias_delete_description = "Delete specified aliases or all aliases if --all is used" alias_delete_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description=alias_delete_description) alias_delete_parser.add_argument('-a', '--all', action='store_true', help="delete all aliases") alias_delete_parser.add_argument( 'names', nargs=argparse.ZERO_OR_MORE, help='alias(es) to delete', choices_provider=_get_alias_completion_items, descriptive_header=_alias_completion_table.generate_header(), ) @as_subcommand_to('alias', 'delete', alias_delete_parser, help=alias_delete_help) def _alias_delete(self, args: argparse.Namespace) -> None: """Delete aliases""" self.last_result = True if args.all: self.aliases.clear() self.poutput("All aliases deleted") elif not args.names: self.perror("Either --all or alias name(s) must be specified") self.last_result = False else: for cur_name in utils.remove_duplicates(args.names): if cur_name in self.aliases: del self.aliases[cur_name] self.poutput(f"Alias '{cur_name}' deleted") else: self.perror(f"Alias '{cur_name}' does not exist") # alias -> list alias_list_help = "list aliases" alias_list_description = ( "List specified aliases in a reusable form that can be saved to a startup\n" "script to preserve aliases across sessions\n" "\n" "Without arguments, all aliases will be listed." ) alias_list_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description=alias_list_description) alias_list_parser.add_argument( 'names', nargs=argparse.ZERO_OR_MORE, help='alias(es) to list', choices_provider=_get_alias_completion_items, descriptive_header=_alias_completion_table.generate_header(), ) @as_subcommand_to('alias', 'list', alias_list_parser, help=alias_list_help) def _alias_list(self, args: argparse.Namespace) -> None: """List some or all aliases as 'alias create' commands""" self.last_result = {} # Dict[alias_name, alias_value] tokens_to_quote = constants.REDIRECTION_TOKENS tokens_to_quote.extend(self.statement_parser.terminators) if args.names: to_list = utils.remove_duplicates(args.names) else: to_list = sorted(self.aliases, key=self.default_sort_key) not_found: List[str] = [] for name in to_list: if name not in self.aliases: not_found.append(name) continue # Quote redirection and terminator tokens for the 'alias create' command tokens = shlex_split(self.aliases[name]) command = tokens[0] command_args = tokens[1:] utils.quote_specific_tokens(command_args, tokens_to_quote) val = command if command_args: val += ' ' + ' '.join(command_args) self.poutput(f"alias create {name} {val}") self.last_result[name] = val for name in not_found: self.perror(f"Alias '{name}' not found") ############################################################# # Parsers and functions for macro command and subcommands ############################################################# # Top-level parser for macro macro_description = "Manage macros\n" "\n" "A macro is similar to an alias, but it can contain argument placeholders." macro_epilog = "See also:\n" " alias" macro_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description=macro_description, epilog=macro_epilog) macro_parser.add_subparsers(metavar='SUBCOMMAND', required=True) # Preserve quotes since we are passing strings to other commands @with_argparser(macro_parser, preserve_quotes=True) def do_macro(self, args: argparse.Namespace) -> None: """Manage macros""" # Call handler for whatever subcommand was selected handler = args.cmd2_handler.get() handler(args) # macro -> create macro_create_help = "create or overwrite a macro" macro_create_description = "Create or overwrite a macro" macro_create_epilog = ( "A macro is similar to an alias, but it can contain argument placeholders.\n" "Arguments are expressed when creating a macro using {#} notation where {1}\n" "means the first argument.\n" "\n" "The following creates a macro called my_macro that expects two arguments:\n" "\n" " macro create my_macro make_dinner --meat {1} --veggie {2}\n" "\n" "When the macro is called, the provided arguments are resolved and the\n" "assembled command is run. For example:\n" "\n" " my_macro beef broccoli ---> make_dinner --meat beef --veggie broccoli\n" "\n" "Notes:\n" " To use the literal string {1} in your command, escape it this way: {{1}}.\n" "\n" " Extra arguments passed to a macro are appended to resolved command.\n" "\n" " An argument number can be repeated in a macro. In the following example the\n" " first argument will populate both {1} instances.\n" "\n" " macro create ft file_taxes -p {1} -q {2} -r {1}\n" "\n" " To quote an argument in the resolved command, quote it during creation.\n" "\n" " macro create backup !cp \"{1}\" \"{1}.orig\"\n" "\n" " If you want to use redirection, pipes, or terminators in the value of the\n" " macro, then quote them.\n" "\n" " macro create show_results print_results -type {1} \"|\" less\n" "\n" " Because macros do not resolve until after hitting Enter, tab completion\n" " will only complete paths while typing a macro." ) macro_create_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER( description=macro_create_description, epilog=macro_create_epilog ) macro_create_parser.add_argument('name', help='name of this macro') macro_create_parser.add_argument( 'command', help='what the macro resolves to', choices_provider=_get_commands_aliases_and_macros_for_completion ) macro_create_parser.add_argument( 'command_args', nargs=argparse.REMAINDER, help='arguments to pass to command', completer=path_complete ) @as_subcommand_to('macro', 'create', macro_create_parser, help=macro_create_help) def _macro_create(self, args: argparse.Namespace) -> None: """Create or overwrite a macro""" self.last_result = False # Validate the macro name valid, errmsg = self.statement_parser.is_valid_command(args.name) if not valid: self.perror(f"Invalid macro name: {errmsg}") return if args.name in self.get_all_commands(): self.perror("Macro cannot have the same name as a command") return if args.name in self.aliases: self.perror("Macro cannot have the same name as an alias") return # Unquote redirection and terminator tokens tokens_to_unquote = constants.REDIRECTION_TOKENS tokens_to_unquote.extend(self.statement_parser.terminators) utils.unquote_specific_tokens(args.command_args, tokens_to_unquote) # Build the macro value string value = args.command if args.command_args: value += ' ' + ' '.join(args.command_args) # Find all normal arguments arg_list = [] normal_matches = re.finditer(MacroArg.macro_normal_arg_pattern, value) max_arg_num = 0 arg_nums = set() while True: try: cur_match = normal_matches.__next__() # Get the number string between the braces cur_num_str = re.findall(MacroArg.digit_pattern, cur_match.group())[0] cur_num = int(cur_num_str) if cur_num < 1: self.perror("Argument numbers must be greater than 0") return arg_nums.add(cur_num) if cur_num > max_arg_num: max_arg_num = cur_num arg_list.append(MacroArg(start_index=cur_match.start(), number_str=cur_num_str, is_escaped=False)) except StopIteration: break # Make sure the argument numbers are continuous if len(arg_nums) != max_arg_num: self.perror(f"Not all numbers between 1 and {max_arg_num} are present in the argument placeholders") return # Find all escaped arguments escaped_matches = re.finditer(MacroArg.macro_escaped_arg_pattern, value) while True: try: cur_match = escaped_matches.__next__() # Get the number string between the braces cur_num_str = re.findall(MacroArg.digit_pattern, cur_match.group())[0] arg_list.append(MacroArg(start_index=cur_match.start(), number_str=cur_num_str, is_escaped=True)) except StopIteration: break # Set the macro result = "overwritten" if args.name in self.macros else "created" self.poutput(f"Macro '{args.name}' {result}") self.macros[args.name] = Macro(name=args.name, value=value, minimum_arg_count=max_arg_num, arg_list=arg_list) self.last_result = True # macro -> delete macro_delete_help = "delete macros" macro_delete_description = "Delete specified macros or all macros if --all is used" macro_delete_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description=macro_delete_description) macro_delete_parser.add_argument('-a', '--all', action='store_true', help="delete all macros") macro_delete_parser.add_argument( 'names', nargs=argparse.ZERO_OR_MORE, help='macro(s) to delete', choices_provider=_get_macro_completion_items, descriptive_header=_macro_completion_table.generate_header(), ) @as_subcommand_to('macro', 'delete', macro_delete_parser, help=macro_delete_help) def _macro_delete(self, args: argparse.Namespace) -> None: """Delete macros""" self.last_result = True if args.all: self.macros.clear() self.poutput("All macros deleted") elif not args.names: self.perror("Either --all or macro name(s) must be specified") self.last_result = False else: for cur_name in utils.remove_duplicates(args.names): if cur_name in self.macros: del self.macros[cur_name] self.poutput(f"Macro '{cur_name}' deleted") else: self.perror(f"Macro '{cur_name}' does not exist") # macro -> list macro_list_help = "list macros" macro_list_description = ( "List specified macros in a reusable form that can be saved to a startup script\n" "to preserve macros across sessions\n" "\n" "Without arguments, all macros will be listed." ) macro_list_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description=macro_list_description) macro_list_parser.add_argument( 'names', nargs=argparse.ZERO_OR_MORE, help='macro(s) to list', choices_provider=_get_macro_completion_items, descriptive_header=_macro_completion_table.generate_header(), ) @as_subcommand_to('macro', 'list', macro_list_parser, help=macro_list_help) def _macro_list(self, args: argparse.Namespace) -> None: """List some or all macros as 'macro create' commands""" self.last_result = {} # Dict[macro_name, macro_value] tokens_to_quote = constants.REDIRECTION_TOKENS tokens_to_quote.extend(self.statement_parser.terminators) if args.names: to_list = utils.remove_duplicates(args.names) else: to_list = sorted(self.macros, key=self.default_sort_key) not_found: List[str] = [] for name in to_list: if name not in self.macros: not_found.append(name) continue # Quote redirection and terminator tokens for the 'macro create' command tokens = shlex_split(self.macros[name].value) command = tokens[0] command_args = tokens[1:] utils.quote_specific_tokens(command_args, tokens_to_quote) val = command if command_args: val += ' ' + ' '.join(command_args) self.poutput(f"macro create {name} {val}") self.last_result[name] = val for name in not_found: self.perror(f"Macro '{name}' not found") def complete_help_command(self, text: str, line: str, begidx: int, endidx: int) -> List[str]: """Completes the command argument of help""" # Complete token against topics and visible commands topics = set(self.get_help_topics()) visible_commands = set(self.get_visible_commands()) strs_to_match = list(topics | visible_commands) return self.basic_complete(text, line, begidx, endidx, strs_to_match) def complete_help_subcommands( self, text: str, line: str, begidx: int, endidx: int, arg_tokens: Dict[str, List[str]] ) -> List[str]: """Completes the subcommands argument of help""" # Make sure we have a command whose subcommands we will complete command = arg_tokens['command'][0] if not command: return [] # Check if this command uses argparse if (func := self.cmd_func(command)) is None or (argparser := self._command_parsers.get(func)) is None: return [] completer = argparse_completer.DEFAULT_AP_COMPLETER(argparser, self) return completer.complete_subcommand_help(text, line, begidx, endidx, arg_tokens['subcommands']) help_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER( description="List available commands or provide " "detailed help for a specific command" ) help_parser.add_argument( '-v', '--verbose', action='store_true', help="print a list of all commands with descriptions of each" ) help_parser.add_argument( 'command', nargs=argparse.OPTIONAL, help="command to retrieve help for", completer=complete_help_command ) help_parser.add_argument( 'subcommands', nargs=argparse.REMAINDER, help="subcommand(s) to retrieve help for", completer=complete_help_subcommands ) # Get rid of cmd's complete_help() functions so ArgparseCompleter will complete the help command if getattr(cmd.Cmd, 'complete_help', None) is not None: delattr(cmd.Cmd, 'complete_help') @with_argparser(help_parser) def do_help(self, args: argparse.Namespace) -> None: """List available commands or provide detailed help for a specific command""" self.last_result = True if not args.command or args.verbose: self._help_menu(args.verbose) else: # Getting help for a specific command func = self.cmd_func(args.command) help_func = getattr(self, constants.HELP_FUNC_PREFIX + args.command, None) argparser = None if func is None else self._command_parsers.get(func) # If the command function uses argparse, then use argparse's help if func is not None and argparser is not None: completer = argparse_completer.DEFAULT_AP_COMPLETER(argparser, self) # Set end to blank so the help output matches how it looks when "command -h" is used self.poutput(completer.format_help(args.subcommands), end='') # If there is a help func delegate to do_help elif help_func is not None: super().do_help(args.command) # If there's no help_func __doc__ then format and output it elif func is not None and func.__doc__ is not None: self.poutput(pydoc.getdoc(func)) # If there is no help information then print an error else: err_msg = self.help_error.format(args.command) # Set apply_style to False so help_error's style is not overridden self.perror(err_msg, apply_style=False) self.last_result = False def print_topics(self, header: str, cmds: Optional[List[str]], cmdlen: int, maxcol: int) -> None: """ Print groups of commands and topics in columns and an optional header Override of cmd's print_topics() to handle headers with newlines, ANSI style sequences, and wide characters :param header: string to print above commands being printed :param cmds: list of topics to print :param cmdlen: unused, even by cmd's version :param maxcol: max number of display columns to fit into """ if cmds: self.poutput(header) if self.ruler: divider = utils.align_left('', fill_char=self.ruler, width=ansi.widest_line(header)) self.poutput(divider) self.columnize(cmds, maxcol - 1) self.poutput() def columnize(self, str_list: Optional[List[str]], display_width: int = 80) -> None: """Display a list of single-line strings as a compact set of columns. Override of cmd's columnize() to handle strings with ANSI style sequences and wide characters Each column is only as wide as necessary. Columns are separated by two spaces (one was not legible enough). """ if not str_list: self.poutput("") return nonstrings = [i for i in range(len(str_list)) if not isinstance(str_list[i], str)] if nonstrings: raise TypeError(f"str_list[i] not a string for i in {nonstrings}") size = len(str_list) if size == 1: self.poutput(str_list[0]) return # Try every row count from 1 upwards for nrows in range(1, len(str_list)): ncols = (size + nrows - 1) // nrows colwidths = [] totwidth = -2 for col in range(ncols): colwidth = 0 for row in range(nrows): i = row + nrows * col if i >= size: break x = str_list[i] colwidth = max(colwidth, ansi.style_aware_wcswidth(x)) colwidths.append(colwidth) totwidth += colwidth + 2 if totwidth > display_width: break if totwidth <= display_width: break else: # The output is wider than display_width. Print 1 column with each string on its own row. nrows = len(str_list) ncols = 1 colwidths = [1] for row in range(nrows): texts = [] for col in range(ncols): i = row + nrows * col if i >= size: x = "" else: x = str_list[i] texts.append(x) while texts and not texts[-1]: del texts[-1] for col in range(len(texts)): texts[col] = utils.align_left(texts[col], width=colwidths[col]) self.poutput(" ".join(texts)) def _help_menu(self, verbose: bool = False) -> None: """Show a list of commands which help can be displayed for""" cmds_cats, cmds_doc, cmds_undoc, help_topics = self._build_command_info() if not cmds_cats: # No categories found, fall back to standard behavior self.poutput(self.doc_leader) self._print_topics(self.doc_header, cmds_doc, verbose) else: # Categories found, Organize all commands by category self.poutput(self.doc_leader) self.poutput(self.doc_header, end="\n\n") for category in sorted(cmds_cats.keys(), key=self.default_sort_key): self._print_topics(category, cmds_cats[category], verbose) self._print_topics(self.default_category, cmds_doc, verbose) self.print_topics(self.misc_header, help_topics, 15, 80) self.print_topics(self.undoc_header, cmds_undoc, 15, 80) def _build_command_info(self) -> Tuple[Dict[str, List[str]], List[str], List[str], List[str]]: # Get a sorted list of help topics help_topics = sorted(self.get_help_topics(), key=self.default_sort_key) # Get a sorted list of visible command names visible_commands = sorted(self.get_visible_commands(), key=self.default_sort_key) cmds_doc: List[str] = [] cmds_undoc: List[str] = [] cmds_cats: Dict[str, List[str]] = {} for command in visible_commands: func = cast(CommandFunc, self.cmd_func(command)) has_help_func = False has_parser = func in self._command_parsers if command in help_topics: # Prevent the command from showing as both a command and help topic in the output help_topics.remove(command) # Non-argparse commands can have help_functions for their documentation has_help_func = not has_parser if hasattr(func, constants.CMD_ATTR_HELP_CATEGORY): category: str = getattr(func, constants.CMD_ATTR_HELP_CATEGORY) cmds_cats.setdefault(category, []) cmds_cats[category].append(command) elif func.__doc__ or has_help_func or has_parser: cmds_doc.append(command) else: cmds_undoc.append(command) return cmds_cats, cmds_doc, cmds_undoc, help_topics def _print_topics(self, header: str, cmds: List[str], verbose: bool) -> None: """Customized version of print_topics that can switch between verbose or traditional output""" import io if cmds: if not verbose: self.print_topics(header, cmds, 15, 80) else: # Find the widest command widest = max([ansi.style_aware_wcswidth(command) for command in cmds]) # Define the table structure name_column = Column('', width=max(widest, 20)) desc_column = Column('', width=80) topic_table = SimpleTable([name_column, desc_column], divider_char=self.ruler) # Build the topic table table_str_buf = io.StringIO() if header: table_str_buf.write(header + "\n") divider = topic_table.generate_divider() if divider: table_str_buf.write(divider + "\n") # Try to get the documentation string for each command topics = self.get_help_topics() for command in cmds: if (cmd_func := self.cmd_func(command)) is None: continue doc: Optional[str] # If this is an argparse command, use its description. if (cmd_parser := self._command_parsers.get(cmd_func)) is not None: doc = cmd_parser.description # Non-argparse commands can have help_functions for their documentation elif command in topics: help_func = getattr(self, constants.HELP_FUNC_PREFIX + command) result = io.StringIO() # try to redirect system stdout with redirect_stdout(result): # save our internal stdout stdout_orig = self.stdout try: # redirect our internal stdout self.stdout = cast(TextIO, result) help_func() finally: # restore internal stdout self.stdout = stdout_orig doc = result.getvalue() else: doc = cmd_func.__doc__ # Attempt to locate the first documentation block cmd_desc = strip_doc_annotations(doc) if doc else '' # Add this command to the table table_row = topic_table.generate_data_row([command, cmd_desc]) table_str_buf.write(table_row + '\n') self.poutput(table_str_buf.getvalue()) shortcuts_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description="List available shortcuts") @with_argparser(shortcuts_parser) def do_shortcuts(self, _: argparse.Namespace) -> None: """List available shortcuts""" # Sort the shortcut tuples by name sorted_shortcuts = sorted(self.statement_parser.shortcuts, key=lambda x: self.default_sort_key(x[0])) result = "\n".join('{}: {}'.format(sc[0], sc[1]) for sc in sorted_shortcuts) self.poutput(f"Shortcuts for other commands:\n{result}") self.last_result = True eof_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER( description="Called when Ctrl-D is pressed", epilog=INTERNAL_COMMAND_EPILOG ) @with_argparser(eof_parser) def do_eof(self, _: argparse.Namespace) -> Optional[bool]: """ Called when Ctrl-D is pressed and calls quit with no arguments. This can be overridden if quit should be called differently. """ self.poutput() # self.last_result will be set by do_quit() return self.do_quit('') quit_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description="Exit this application") @with_argparser(quit_parser) def do_quit(self, _: argparse.Namespace) -> Optional[bool]: """Exit this application""" # Return True to stop the command loop self.last_result = True return True def select(self, opts: Union[str, List[str], List[Tuple[Any, Optional[str]]]], prompt: str = 'Your choice? ') -> Any: """Presents a numbered menu to the user. Modeled after the bash shell's SELECT. Returns the item chosen. Argument ``opts`` can be: | a single string -> will be split into one-word options | a list of strings -> will be offered as options | a list of tuples -> interpreted as (value, text), so that the return value can differ from the text advertised to the user""" local_opts: Union[List[str], List[Tuple[Any, Optional[str]]]] if isinstance(opts, str): local_opts = cast(List[Tuple[Any, Optional[str]]], list(zip(opts.split(), opts.split()))) else: local_opts = opts fulloptions: List[Tuple[Any, Optional[str]]] = [] for opt in local_opts: if isinstance(opt, str): fulloptions.append((opt, opt)) else: try: fulloptions.append((opt[0], opt[1])) except IndexError: fulloptions.append((opt[0], opt[0])) for idx, (_, text) in enumerate(fulloptions): self.poutput(' %2d. %s' % (idx + 1, text)) while True: try: response = self.read_input(prompt) except EOFError: response = '' self.poutput() except KeyboardInterrupt as ex: self.poutput('^C') raise ex if not response: continue try: choice = int(response) if choice < 1: raise IndexError return fulloptions[choice - 1][0] except (ValueError, IndexError): self.poutput(f"'{response}' isn't a valid choice. Pick a number between 1 and {len(fulloptions)}:") def complete_set_value( self, text: str, line: str, begidx: int, endidx: int, arg_tokens: Dict[str, List[str]] ) -> List[str]: """Completes the value argument of set""" param = arg_tokens['param'][0] try: settable = self.settables[param] except KeyError: raise CompletionError(param + " is not a settable parameter") # Create a parser with a value field based on this settable settable_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(parents=[Cmd.set_parser_parent]) # Settables with choices list the values of those choices instead of the arg name # in help text and this shows in tab completion hints. Set metavar to avoid this. arg_name = 'value' settable_parser.add_argument( arg_name, metavar=arg_name, help=settable.description, choices=settable.choices, # type: ignore[arg-type] choices_provider=settable.choices_provider, completer=settable.completer, ) completer = argparse_completer.DEFAULT_AP_COMPLETER(settable_parser, self) # Use raw_tokens since quotes have been preserved _, raw_tokens = self.tokens_for_completion(line, begidx, endidx) return completer.complete(text, line, begidx, endidx, raw_tokens[1:]) # When tab completing value, we recreate the set command parser with a value argument specific to # the settable being edited. To make this easier, define a parent parser with all the common elements. set_description = ( "Set a settable parameter or show current settings of parameters\n" "Call without arguments for a list of all settable parameters with their values.\n" "Call with just param to view that parameter's value." ) set_parser_parent = argparse_custom.DEFAULT_ARGUMENT_PARSER(description=set_description, add_help=False) set_parser_parent.add_argument( 'param', nargs=argparse.OPTIONAL, help='parameter to set or view', choices_provider=_get_settable_completion_items, descriptive_header=_settable_completion_table.generate_header(), ) # Create the parser for the set command set_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(parents=[set_parser_parent]) set_parser.add_argument( 'value', nargs=argparse.OPTIONAL, help='new value for settable', completer=complete_set_value, suppress_tab_hint=True ) # Preserve quotes so users can pass in quoted empty strings and flags (e.g. -h) as the value @with_argparser(set_parser, preserve_quotes=True) def do_set(self, args: argparse.Namespace) -> None: """Set a settable parameter or show current settings of parameters""" self.last_result = False if not self.settables: self.pwarning("There are no settable parameters") return if args.param: try: settable = self.settables[args.param] except KeyError: self.perror(f"Parameter '{args.param}' not supported (type 'set' for list of parameters).") return if args.value: # Try to update the settable's value try: orig_value = settable.get_value() settable.set_value(utils.strip_quotes(args.value)) except Exception as ex: self.perror(f"Error setting {args.param}: {ex}") else: self.poutput(f"{args.param} - was: {orig_value!r}\nnow: {settable.get_value()!r}") self.last_result = True return # Show one settable to_show = [args.param] else: # Show all settables to_show = list(self.settables.keys()) # Define the table structure name_label = 'Name' max_name_width = max([ansi.style_aware_wcswidth(param) for param in to_show]) max_name_width = max(max_name_width, ansi.style_aware_wcswidth(name_label)) cols: List[Column] = [ Column(name_label, width=max_name_width), Column('Value', width=30), Column('Description', width=60), ] table = SimpleTable(cols, divider_char=self.ruler) self.poutput(table.generate_header()) # Build the table and populate self.last_result self.last_result = {} # Dict[settable_name, settable_value] for param in sorted(to_show, key=self.default_sort_key): settable = self.settables[param] row_data = [param, settable.get_value(), settable.description] self.poutput(table.generate_data_row(row_data)) self.last_result[param] = settable.get_value() shell_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description="Execute a command as if at the OS prompt") shell_parser.add_argument('command', help='the command to run', completer=shell_cmd_complete) shell_parser.add_argument( 'command_args', nargs=argparse.REMAINDER, help='arguments to pass to command', completer=path_complete ) # Preserve quotes since we are passing these strings to the shell @with_argparser(shell_parser, preserve_quotes=True) def do_shell(self, args: argparse.Namespace) -> None: """Execute a command as if at the OS prompt""" import signal import subprocess kwargs: Dict[str, Any] = dict() # Set OS-specific parameters if sys.platform.startswith('win'): # Windows returns STATUS_CONTROL_C_EXIT when application stopped by Ctrl-C ctrl_c_ret_code = 0xC000013A else: # On POSIX, Popen() returns -SIGINT when application stopped by Ctrl-C ctrl_c_ret_code = signal.SIGINT.value * -1 # On POSIX with shell=True, Popen() defaults to /bin/sh as the shell. # sh reports an incorrect return code for some applications when Ctrl-C is pressed within that # application (e.g. less). Since sh received the SIGINT, it sets the return code to reflect being # closed by SIGINT even though less did not exit upon a Ctrl-C press. In the same situation, other # shells like bash and zsh report the actual return code of less. Therefore, we will try to run the # user's preferred shell which most likely will be something other than sh. This also allows the user # to run builtin commands of their preferred shell. shell = os.environ.get("SHELL") if shell: kwargs['executable'] = shell # Create a list of arguments to shell tokens = [args.command] + args.command_args # Expand ~ where needed utils.expand_user_in_tokens(tokens) expanded_command = ' '.join(tokens) # Prevent KeyboardInterrupts while in the shell process. The shell process will # still receive the SIGINT since it is in the same process group as us. with self.sigint_protection: # For any stream that is a StdSim, we will use a pipe so we can capture its output proc = subprocess.Popen( # type: ignore[call-overload] expanded_command, stdout=subprocess.PIPE if isinstance(self.stdout, utils.StdSim) else self.stdout, # type: ignore[unreachable] stderr=subprocess.PIPE if isinstance(sys.stderr, utils.StdSim) else sys.stderr, # type: ignore[unreachable] shell=True, **kwargs, ) proc_reader = utils.ProcReader(proc, cast(TextIO, self.stdout), sys.stderr) # type: ignore[arg-type] proc_reader.wait() # Save the return code of the application for use in a pyscript self.last_result = proc.returncode # If the process was stopped by Ctrl-C, then inform the caller by raising a KeyboardInterrupt. # This is to support things like stop_on_keyboard_interrupt in runcmds_plus_hooks(). if proc.returncode == ctrl_c_ret_code: self._raise_keyboard_interrupt() @staticmethod def _reset_py_display() -> None: """ Resets the dynamic objects in the sys module that the py and ipy consoles fight over. When a Python console starts it adopts certain display settings if they've already been set. If an ipy console has previously been run, then py uses its settings and ends up looking like an ipy console in terms of prompt and exception text. This method forces the Python console to create its own display settings since they won't exist. IPython does not have this problem since it always overwrites the display settings when it is run. Therefore, this method only needs to be called before creating a Python console. """ # Delete any prompts that have been set attributes = ['ps1', 'ps2', 'ps3'] for cur_attr in attributes: try: del sys.__dict__[cur_attr] except KeyError: pass # Reset functions sys.displayhook = sys.__displayhook__ sys.excepthook = sys.__excepthook__ def _set_up_py_shell_env(self, interp: InteractiveConsole) -> _SavedCmd2Env: """ Set up interactive Python shell environment :return: Class containing saved up cmd2 environment """ cmd2_env = _SavedCmd2Env() # Set up readline for Python shell if rl_type != RlType.NONE: # Save cmd2 history for i in range(1, readline.get_current_history_length() + 1): cmd2_env.history.append(readline.get_history_item(i)) readline.clear_history() # Restore py's history for item in self._py_history: readline.add_history(item) if self._completion_supported(): # Set up tab completion for the Python console # rlcompleter relies on the default settings of the Python readline module if rl_type == RlType.GNU: cmd2_env.readline_settings.basic_quotes = cast( bytes, ctypes.cast(rl_basic_quote_characters, ctypes.c_void_p).value ) rl_basic_quote_characters.value = orig_rl_basic_quotes if 'gnureadline' in sys.modules: # rlcompleter imports readline by name, so it won't use gnureadline # Force rlcompleter to use gnureadline instead so it has our settings and history if 'readline' in sys.modules: cmd2_env.readline_module = sys.modules['readline'] sys.modules['readline'] = sys.modules['gnureadline'] cmd2_env.readline_settings.delims = readline.get_completer_delims() readline.set_completer_delims(orig_rl_delims) # rlcompleter will not need cmd2's custom display function # This will be restored by cmd2 the next time complete() is called if rl_type == RlType.GNU: readline.set_completion_display_matches_hook(None) elif rl_type == RlType.PYREADLINE: readline.rl.mode._display_completions = orig_pyreadline_display # Save off the current completer and set a new one in the Python console # Make sure it tab completes from its locals() dictionary cmd2_env.readline_settings.completer = readline.get_completer() interp.runcode("from rlcompleter import Completer") # type: ignore[arg-type] interp.runcode("import readline") # type: ignore[arg-type] interp.runcode("readline.set_completer(Completer(locals()).complete)") # type: ignore[arg-type] # Set up sys module for the Python console self._reset_py_display() cmd2_env.sys_stdout = sys.stdout sys.stdout = self.stdout # type: ignore[assignment] cmd2_env.sys_stdin = sys.stdin sys.stdin = self.stdin # type: ignore[assignment] return cmd2_env def _restore_cmd2_env(self, cmd2_env: _SavedCmd2Env) -> None: """ Restore cmd2 environment after exiting an interactive Python shell :param cmd2_env: the environment settings to restore """ sys.stdout = cmd2_env.sys_stdout # type: ignore[assignment] sys.stdin = cmd2_env.sys_stdin # type: ignore[assignment] # Set up readline for cmd2 if rl_type != RlType.NONE: # Save py's history self._py_history.clear() for i in range(1, readline.get_current_history_length() + 1): self._py_history.append(readline.get_history_item(i)) readline.clear_history() # Restore cmd2's history for item in cmd2_env.history: readline.add_history(item) if self._completion_supported(): # Restore cmd2's tab completion settings readline.set_completer(cmd2_env.readline_settings.completer) readline.set_completer_delims(cmd2_env.readline_settings.delims) if rl_type == RlType.GNU: rl_basic_quote_characters.value = cmd2_env.readline_settings.basic_quotes if 'gnureadline' in sys.modules: # Restore what the readline module pointed to if cmd2_env.readline_module is None: del sys.modules['readline'] else: sys.modules['readline'] = cmd2_env.readline_module def _run_python(self, *, pyscript: Optional[str] = None) -> Optional[bool]: """ Called by do_py() and do_run_pyscript(). If pyscript is None, then this function runs an interactive Python shell. Otherwise, it runs the pyscript file. :param pyscript: optional path to a pyscript file to run. This is intended only to be used by do_run_pyscript() after it sets up sys.argv for the script. (Defaults to None) :return: True if running of commands should stop """ self.last_result = False def py_quit() -> None: """Function callable from the interactive Python console to exit that environment""" raise EmbeddedConsoleExit from .py_bridge import ( PyBridge, ) add_to_history = self.scripts_add_to_history if pyscript else True py_bridge = PyBridge(self, add_to_history=add_to_history) saved_sys_path = None if self.in_pyscript(): self.perror("Recursively entering interactive Python shells is not allowed") return None try: self._in_py = True py_code_to_run = '' # Make a copy of self.py_locals for the locals dictionary in the Python environment we are creating. # This is to prevent pyscripts from editing it. (e.g. locals().clear()). It also ensures a pyscript's # environment won't be filled with data from a previously run pyscript. Only make a shallow copy since # it's OK for py_locals to contain objects which are editable in a pyscript. local_vars = self.py_locals.copy() local_vars[self.py_bridge_name] = py_bridge local_vars['quit'] = py_quit local_vars['exit'] = py_quit if self.self_in_py: local_vars['self'] = self # Handle case where we were called by do_run_pyscript() if pyscript is not None: # Read the script file expanded_filename = os.path.expanduser(pyscript) try: with open(expanded_filename) as f: py_code_to_run = f.read() except OSError as ex: self.perror(f"Error reading script file '{expanded_filename}': {ex}") return None local_vars['__name__'] = '__main__' local_vars['__file__'] = expanded_filename # Place the script's directory at sys.path[0] just as Python does when executing a script saved_sys_path = list(sys.path) sys.path.insert(0, os.path.dirname(os.path.abspath(expanded_filename))) else: # This is the default name chosen by InteractiveConsole when no locals are passed in local_vars['__name__'] = '__console__' # Create the Python interpreter self.last_result = True interp = InteractiveConsole(locals=local_vars) # Check if we are running Python code if py_code_to_run: try: interp.runcode(py_code_to_run) # type: ignore[arg-type] except BaseException: # We don't care about any exception that happened in the Python code pass # Otherwise we will open an interactive Python shell else: cprt = 'Type "help", "copyright", "credits" or "license" for more information.' instructions = ( 'Use `Ctrl-D` (Unix) / `Ctrl-Z` (Windows), `quit()`, `exit()` to exit.\n' f'Run CLI commands with: {self.py_bridge_name}("command ...")' ) banner = f"Python {sys.version} on {sys.platform}\n{cprt}\n\n{instructions}\n" saved_cmd2_env = None try: # Get sigint protection while we set up the Python shell environment with self.sigint_protection: saved_cmd2_env = self._set_up_py_shell_env(interp) # Since quit() or exit() raise an EmbeddedConsoleExit, interact() exits before printing # the exitmsg. Therefore, we will not provide it one and print it manually later. interp.interact(banner=banner, exitmsg='') except BaseException: # We don't care about any exception that happened in the interactive console pass finally: # Get sigint protection while we restore cmd2 environment settings with self.sigint_protection: if saved_cmd2_env is not None: self._restore_cmd2_env(saved_cmd2_env) self.poutput("Now exiting Python shell...") finally: with self.sigint_protection: if saved_sys_path is not None: sys.path = saved_sys_path self._in_py = False return py_bridge.stop py_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description="Run an interactive Python shell") @with_argparser(py_parser) def do_py(self, _: argparse.Namespace) -> Optional[bool]: """ Run an interactive Python shell :return: True if running of commands should stop """ # self.last_resort will be set by _run_python() return self._run_python() run_pyscript_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description="Run a Python script file inside the console") run_pyscript_parser.add_argument('script_path', help='path to the script file', completer=path_complete) run_pyscript_parser.add_argument( 'script_arguments', nargs=argparse.REMAINDER, help='arguments to pass to script', completer=path_complete ) @with_argparser(run_pyscript_parser) def do_run_pyscript(self, args: argparse.Namespace) -> Optional[bool]: """ Run a Python script file inside the console :return: True if running of commands should stop """ self.last_result = False # Expand ~ before placing this path in sys.argv just as a shell would args.script_path = os.path.expanduser(args.script_path) # Add some protection against accidentally running a non-Python file. The happens when users # mix up run_script and run_pyscript. if not args.script_path.endswith('.py'): self.pwarning(f"'{args.script_path}' does not have a .py extension") selection = self.select('Yes No', 'Continue to try to run it as a Python script? ') if selection != 'Yes': return None # Save current command line arguments orig_args = sys.argv try: # Overwrite sys.argv to allow the script to take command line arguments sys.argv = [args.script_path] + args.script_arguments # self.last_resort will be set by _run_python() py_return = self._run_python(pyscript=args.script_path) finally: # Restore command line arguments to original state sys.argv = orig_args return py_return ipython_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description="Run an interactive IPython shell") @with_argparser(ipython_parser) def do_ipy(self, _: argparse.Namespace) -> Optional[bool]: # pragma: no cover """ Enter an interactive IPython shell :return: True if running of commands should stop """ self.last_result = False # Detect whether IPython is installed try: import traitlets.config.loader as TraitletsLoader # type: ignore[import] # Allow users to install ipython from a cmd2 prompt when needed and still have ipy command work try: start_ipython # noqa F823 except NameError: from IPython import start_ipython # type: ignore[import] from IPython.terminal.interactiveshell import ( # type: ignore[import] TerminalInteractiveShell, ) from IPython.terminal.ipapp import ( # type: ignore[import] TerminalIPythonApp, ) except ImportError: self.perror("IPython package is not installed") return None from .py_bridge import ( PyBridge, ) if self.in_pyscript(): self.perror("Recursively entering interactive Python shells is not allowed") return None self.last_result = True try: self._in_py = True py_bridge = PyBridge(self) # Make a copy of self.py_locals for the locals dictionary in the IPython environment we are creating. # This is to prevent ipy from editing it. (e.g. locals().clear()). Only make a shallow copy since # it's OK for py_locals to contain objects which are editable in ipy. local_vars = self.py_locals.copy() local_vars[self.py_bridge_name] = py_bridge if self.self_in_py: local_vars['self'] = self # Configure IPython config = TraitletsLoader.Config() # type: ignore config.InteractiveShell.banner2 = ( 'Entering an IPython shell. Type exit, quit, or Ctrl-D to exit.\n' f'Run CLI commands with: {self.py_bridge_name}("command ...")\n' ) # Start IPython start_ipython(config=config, argv=[], user_ns=local_vars) # type: ignore[no-untyped-call] self.poutput("Now exiting IPython shell...") # The IPython application is a singleton and won't be recreated next time # this function runs. That's a problem since the contents of local_vars # may need to be changed. Therefore, we must destroy all instances of the # relevant classes. TerminalIPythonApp.clear_instance() TerminalInteractiveShell.clear_instance() return py_bridge.stop finally: self._in_py = False history_description = "View, run, edit, save, or clear previously entered commands" history_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description=history_description) history_action_group = history_parser.add_mutually_exclusive_group() history_action_group.add_argument('-r', '--run', action='store_true', help='run selected history items') history_action_group.add_argument('-e', '--edit', action='store_true', help='edit and then run selected history items') history_action_group.add_argument( '-o', '--output_file', metavar='FILE', help='output commands to a script file, implies -s', completer=path_complete ) history_action_group.add_argument( '-t', '--transcript', metavar='TRANSCRIPT_FILE', help='output commands and results to a transcript file,\nimplies -s', completer=path_complete, ) history_action_group.add_argument('-c', '--clear', action='store_true', help='clear all history') history_format_group = history_parser.add_argument_group(title='formatting') history_format_group.add_argument( '-s', '--script', action='store_true', help='output commands in script format, i.e. without command\n' 'numbers' ) history_format_group.add_argument( '-x', '--expanded', action='store_true', help='output fully parsed commands with any aliases and\n' 'macros expanded, instead of typed commands', ) history_format_group.add_argument( '-v', '--verbose', action='store_true', help='display history and include expanded commands if they\n' 'differ from the typed command', ) history_format_group.add_argument( '-a', '--all', action='store_true', help='display all commands, including ones persisted from\n' 'previous sessions' ) history_arg_help = ( "empty all history items\n" "a one history item by number\n" "a..b, a:b, a:, ..b items by indices (inclusive)\n" "string items containing string\n" "/regex/ items matching regular expression" ) history_parser.add_argument('arg', nargs=argparse.OPTIONAL, help=history_arg_help) @with_argparser(history_parser) def do_history(self, args: argparse.Namespace) -> Optional[bool]: """ View, run, edit, save, or clear previously entered commands :return: True if running of commands should stop """ self.last_result = False # -v must be used alone with no other options if args.verbose: if args.clear or args.edit or args.output_file or args.run or args.transcript or args.expanded or args.script: self.poutput("-v cannot be used with any other options") self.poutput(self.history_parser.format_usage()) return None # -s and -x can only be used if none of these options are present: [-c -r -e -o -t] if (args.script or args.expanded) and (args.clear or args.edit or args.output_file or args.run or args.transcript): self.poutput("-s and -x cannot be used with -c, -r, -e, -o, or -t") self.poutput(self.history_parser.format_usage()) return None if args.clear: self.last_result = True # Clear command and readline history self.history.clear() if self.persistent_history_file: try: os.remove(self.persistent_history_file) except FileNotFoundError: pass except OSError as ex: self.perror(f"Error removing history file '{self.persistent_history_file}': {ex}") self.last_result = False return None if rl_type != RlType.NONE: readline.clear_history() return None # If an argument was supplied, then retrieve partial contents of the history, otherwise retrieve it all history = self._get_history(args) if args.run: if not args.arg: self.perror("Cowardly refusing to run all previously entered commands.") self.perror("If this is what you want to do, specify '1:' as the range of history.") else: stop = self.runcmds_plus_hooks(list(history.values())) self.last_result = True return stop elif args.edit: fd, fname = tempfile.mkstemp(suffix='.txt', text=True) fobj: TextIO with os.fdopen(fd, 'w') as fobj: for command in history.values(): if command.statement.multiline_command: fobj.write(f'{command.expanded}\n') else: fobj.write(f'{command.raw}\n') try: self.run_editor(fname) # self.last_resort will be set by do_run_script() return self.do_run_script(utils.quote_string(fname)) finally: os.remove(fname) elif args.output_file: full_path = os.path.abspath(os.path.expanduser(args.output_file)) try: with open(full_path, 'w') as fobj: for item in history.values(): if item.statement.multiline_command: fobj.write(f"{item.expanded}\n") else: fobj.write(f"{item.raw}\n") plural = '' if len(history) == 1 else 's' except OSError as ex: self.perror(f"Error saving history file '{full_path}': {ex}") else: self.pfeedback(f"{len(history)} command{plural} saved to {full_path}") self.last_result = True elif args.transcript: # self.last_resort will be set by _generate_transcript() self._generate_transcript(list(history.values()), args.transcript) else: # Display the history items retrieved for idx, hi in history.items(): self.poutput(hi.pr(idx, script=args.script, expanded=args.expanded, verbose=args.verbose)) self.last_result = history return None def _get_history(self, args: argparse.Namespace) -> 'OrderedDict[int, HistoryItem]': """If an argument was supplied, then retrieve partial contents of the history; otherwise retrieve entire history. This function returns a dictionary with history items keyed by their 1-based index in ascending order. """ if args.arg: try: int_arg = int(args.arg) return OrderedDict({int_arg: self.history.get(int_arg)}) except ValueError: pass if '..' in args.arg or ':' in args.arg: # Get a slice of history history = self.history.span(args.arg, args.all) elif args.arg.startswith(r'/') and args.arg.endswith(r'/'): history = self.history.regex_search(args.arg, args.all) else: history = self.history.str_search(args.arg, args.all) else: # Get a copy of the history so it doesn't get mutated while we are using it history = self.history.span(':', args.all) return history def _initialize_history(self, hist_file: str) -> None: """Initialize history using history related attributes :param hist_file: optional path to persistent history file. If specified, then history from previous sessions will be included. Additionally, all history will be written to this file when the application exits. """ self.history = History() # With no persistent history, nothing else in this method is relevant if not hist_file: self.persistent_history_file = hist_file return hist_file = os.path.abspath(os.path.expanduser(hist_file)) # On Windows, trying to open a directory throws a permission # error, not a `IsADirectoryError`. So we'll check it ourselves. if os.path.isdir(hist_file): self.perror(f"Persistent history file '{hist_file}' is a directory") return # Create the directory for the history file if it doesn't already exist hist_file_dir = os.path.dirname(hist_file) try: os.makedirs(hist_file_dir, exist_ok=True) except OSError as ex: self.perror(f"Error creating persistent history file directory '{hist_file_dir}': {ex}") return # Read history file try: with open(hist_file, 'rb') as fobj: compressed_bytes = fobj.read() except FileNotFoundError: compressed_bytes = bytes() except OSError as ex: self.perror(f"Cannot read persistent history file '{hist_file}': {ex}") return # Register a function to write history at save import atexit self.persistent_history_file = hist_file atexit.register(self._persist_history) # Empty or nonexistent history file. Nothing more to do. if not compressed_bytes: return # Decompress history data try: import lzma as decompress_lib decompress_exceptions: Tuple[type[Exception]] = (decompress_lib.LZMAError,) except ModuleNotFoundError: # pragma: no cover import bz2 as decompress_lib # type: ignore[no-redef] decompress_exceptions: Tuple[type[Exception]] = (OSError, ValueError) # type: ignore[no-redef] try: history_json = decompress_lib.decompress(compressed_bytes).decode(encoding='utf-8') except decompress_exceptions as ex: self.perror( f"Error decompressing persistent history data '{hist_file}': {ex}\n" f"The history file will be recreated when this application exits." ) return # Decode history json import json try: self.history = History.from_json(history_json) except (json.JSONDecodeError, KeyError, ValueError) as ex: self.perror( f"Error processing persistent history data '{hist_file}': {ex}\n" f"The history file will be recreated when this application exits." ) return self.history.start_session() # Populate readline history if rl_type != RlType.NONE: for item in self.history: formatted_command = single_line_format(item.statement) # If formatted command is different than the previous history item, add it cur_history_length = readline.get_current_history_length() if cur_history_length == 0 or formatted_command != readline.get_history_item(cur_history_length): readline.add_history(formatted_command) def _persist_history(self) -> None: """Write history out to the persistent history file as compressed JSON""" if not self.persistent_history_file: return try: import lzma as compress_lib except ModuleNotFoundError: # pragma: no cover import bz2 as compress_lib # type: ignore[no-redef] self.history.truncate(self._persistent_history_length) history_json = self.history.to_json() compressed_bytes = compress_lib.compress(history_json.encode(encoding='utf-8')) try: with open(self.persistent_history_file, 'wb') as fobj: fobj.write(compressed_bytes) except OSError as ex: self.perror(f"Cannot write persistent history file '{self.persistent_history_file}': {ex}") def _generate_transcript( self, history: Union[List[HistoryItem], List[str]], transcript_file: str, *, add_to_history: bool = True, ) -> None: """Generate a transcript file from a given history of commands""" self.last_result = False # Validate the transcript file path to make sure directory exists and write access is available transcript_path = os.path.abspath(os.path.expanduser(transcript_file)) transcript_dir = os.path.dirname(transcript_path) if not os.path.isdir(transcript_dir) or not os.access(transcript_dir, os.W_OK): self.perror(f"'{transcript_dir}' is not a directory or you don't have write access") return commands_run = 0 try: with self.sigint_protection: # Disable echo while we manually redirect stdout to a StringIO buffer saved_echo = self.echo saved_stdout = self.stdout self.echo = False # The problem with supporting regular expressions in transcripts # is that they shouldn't be processed in the command, just the output. # In addition, when we generate a transcript, any slashes in the output # are not really intended to indicate regular expressions, so they should # be escaped. # # We have to jump through some hoops here in order to catch the commands # separately from the output and escape the slashes in the output. transcript = '' for history_item in history: # build the command, complete with prompts. When we replay # the transcript, we look for the prompts to separate # the command from the output first = True command = '' if isinstance(history_item, HistoryItem): history_item = history_item.raw for line in history_item.splitlines(): if first: command += f"{self.prompt}{line}\n" first = False else: command += f"{self.continuation_prompt}{line}\n" transcript += command # Use a StdSim object to capture output stdsim = utils.StdSim(cast(TextIO, self.stdout)) self.stdout = cast(TextIO, stdsim) # then run the command and let the output go into our buffer try: stop = self.onecmd_plus_hooks( history_item, add_to_history=add_to_history, raise_keyboard_interrupt=True, ) except KeyboardInterrupt as ex: self.perror(ex) stop = True commands_run += 1 # add the regex-escaped output to the transcript transcript += stdsim.getvalue().replace('/', r'\/') # check if we are supposed to stop if stop: break finally: with self.sigint_protection: # Restore altered attributes to their original state self.echo = saved_echo self.stdout = cast(TextIO, saved_stdout) # Check if all commands ran if commands_run < len(history): self.pwarning(f"Command {commands_run} triggered a stop and ended transcript generation early") # finally, we can write the transcript out to the file try: with open(transcript_path, 'w') as fout: fout.write(transcript) except OSError as ex: self.perror(f"Error saving transcript file '{transcript_path}': {ex}") else: # and let the user know what we did if commands_run == 1: plural = 'command and its output' else: plural = 'commands and their outputs' self.pfeedback(f"{commands_run} {plural} saved to transcript file '{transcript_path}'") self.last_result = True edit_description = ( "Run a text editor and optionally open a file with it\n" "\n" "The editor used is determined by a settable parameter. To set it:\n" "\n" " set editor (program-name)" ) edit_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description=edit_description) edit_parser.add_argument( 'file_path', nargs=argparse.OPTIONAL, help="optional path to a file to open in editor", completer=path_complete ) @with_argparser(edit_parser) def do_edit(self, args: argparse.Namespace) -> None: """Run a text editor and optionally open a file with it""" # self.last_result will be set by do_shell() which is called by run_editor() self.run_editor(args.file_path) def run_editor(self, file_path: Optional[str] = None) -> None: """ Run a text editor and optionally open a file with it :param file_path: optional path of the file to edit. Defaults to None. :raises: EnvironmentError if self.editor is not set """ if not self.editor: raise EnvironmentError("Please use 'set editor' to specify your text editing program of choice.") command = utils.quote_string(os.path.expanduser(self.editor)) if file_path: command += " " + utils.quote_string(os.path.expanduser(file_path)) self.do_shell(command) @property def _current_script_dir(self) -> Optional[str]: """Accessor to get the current script directory from the _script_dir LIFO queue.""" if self._script_dir: return self._script_dir[-1] else: return None run_script_description = ( "Run commands in script file that is encoded as either ASCII or UTF-8 text\n" "\n" "Script should contain one command per line, just like the command would be\n" "typed in the console.\n" "\n" "If the -t/--transcript flag is used, this command instead records\n" "the output of the script commands to a transcript for testing purposes.\n" ) run_script_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER(description=run_script_description) run_script_parser.add_argument( '-t', '--transcript', metavar='TRANSCRIPT_FILE', help='record the output of the script as a transcript file', completer=path_complete, ) run_script_parser.add_argument('script_path', help="path to the script file", completer=path_complete) @with_argparser(run_script_parser) def do_run_script(self, args: argparse.Namespace) -> Optional[bool]: """Run commands in script file that is encoded as either ASCII or UTF-8 text. :return: True if running of commands should stop """ self.last_result = False expanded_path = os.path.abspath(os.path.expanduser(args.script_path)) # Add some protection against accidentally running a Python file. The happens when users # mix up run_script and run_pyscript. if expanded_path.endswith('.py'): self.pwarning(f"'{expanded_path}' appears to be a Python file") selection = self.select('Yes No', 'Continue to try to run it as a text script? ') if selection != 'Yes': return None try: # An empty file is not an error, so just return if os.path.getsize(expanded_path) == 0: self.last_result = True return None # Make sure the file is ASCII or UTF-8 encoded text if not utils.is_text_file(expanded_path): self.perror(f"'{expanded_path}' is not an ASCII or UTF-8 encoded text file") return None # Read all lines of the script with open(expanded_path, encoding='utf-8') as target: script_commands = target.read().splitlines() except OSError as ex: self.perror(f"Problem accessing script from '{expanded_path}': {ex}") return None orig_script_dir_count = len(self._script_dir) try: self._script_dir.append(os.path.dirname(expanded_path)) if args.transcript: # self.last_resort will be set by _generate_transcript() self._generate_transcript( script_commands, os.path.expanduser(args.transcript), add_to_history=self.scripts_add_to_history, ) else: stop = self.runcmds_plus_hooks( script_commands, add_to_history=self.scripts_add_to_history, stop_on_keyboard_interrupt=True, ) self.last_result = True return stop finally: with self.sigint_protection: # Check if a script dir was added before an exception occurred if orig_script_dir_count != len(self._script_dir): self._script_dir.pop() return None relative_run_script_description = run_script_description relative_run_script_description += ( "\n\n" "If this is called from within an already-running script, the filename will be\n" "interpreted relative to the already-running script's directory." ) relative_run_script_epilog = "Notes:\n" " This command is intended to only be used within text file scripts." relative_run_script_parser = argparse_custom.DEFAULT_ARGUMENT_PARSER( description=relative_run_script_description, epilog=relative_run_script_epilog ) relative_run_script_parser.add_argument('file_path', help='a file path pointing to a script') @with_argparser(relative_run_script_parser) def do__relative_run_script(self, args: argparse.Namespace) -> Optional[bool]: """ Run commands in script file that is encoded as either ASCII or UTF-8 text :return: True if running of commands should stop """ file_path = args.file_path # NOTE: Relative path is an absolute path, it is just relative to the current script directory relative_path = os.path.join(self._current_script_dir or '', file_path) # self.last_result will be set by do_run_script() return self.do_run_script(utils.quote_string(relative_path)) def _run_transcript_tests(self, transcript_paths: List[str]) -> None: """Runs transcript tests for provided file(s). This is called when either -t is provided on the command line or the transcript_files argument is provided during construction of the cmd2.Cmd instance. :param transcript_paths: list of transcript test file paths """ import time import unittest import cmd2 from .transcript import ( Cmd2TestCase, ) class TestMyAppCase(Cmd2TestCase): cmdapp = self # Validate that there is at least one transcript file transcripts_expanded = utils.files_from_glob_patterns(transcript_paths, access=os.R_OK) if not transcripts_expanded: self.perror('No test files found - nothing to test') self.exit_code = 1 return verinfo = ".".join(map(str, sys.version_info[:3])) num_transcripts = len(transcripts_expanded) plural = '' if len(transcripts_expanded) == 1 else 's' self.poutput(ansi.style(utils.align_center(' cmd2 transcript test ', fill_char='='), bold=True)) self.poutput(f'platform {sys.platform} -- Python {verinfo}, cmd2-{cmd2.__version__}, readline-{rl_type}') self.poutput(f'cwd: {os.getcwd()}') self.poutput(f'cmd2 app: {sys.argv[0]}') self.poutput(ansi.style(f'collected {num_transcripts} transcript{plural}', bold=True)) setattr(self.__class__, 'testfiles', transcripts_expanded) sys.argv = [sys.argv[0]] # the --test argument upsets unittest.main() testcase = TestMyAppCase() stream = cast(TextIO, utils.StdSim(sys.stderr)) runner = unittest.TextTestRunner(stream=stream) start_time = time.time() test_results = runner.run(testcase) execution_time = time.time() - start_time if test_results.wasSuccessful(): ansi.style_aware_write(sys.stderr, stream.read()) finish_msg = f' {num_transcripts} transcript{plural} passed in {execution_time:.3f} seconds ' finish_msg = utils.align_center(finish_msg, fill_char='=') self.psuccess(finish_msg) else: # Strip off the initial traceback which isn't particularly useful for end users error_str = stream.read() end_of_trace = error_str.find('AssertionError:') file_offset = error_str[end_of_trace:].find('File ') start = end_of_trace + file_offset # But print the transcript file name and line number followed by what was expected and what was observed self.perror(error_str[start:]) # Return a failure error code to support automated transcript-based testing self.exit_code = 1 def async_alert(self, alert_msg: str, new_prompt: Optional[str] = None) -> None: # pragma: no cover """ Display an important message to the user while they are at a command line prompt. To the user it appears as if an alert message is printed above the prompt and their current input text and cursor location is left alone. This function needs to acquire self.terminal_lock to ensure a prompt is on screen. Therefore, it is best to acquire the lock before calling this function to avoid raising a RuntimeError. This function is only needed when you need to print an alert or update the prompt while the main thread is blocking at the prompt. Therefore, this should never be called from the main thread. Doing so will raise a RuntimeError. :param alert_msg: the message to display to the user :param new_prompt: If you also want to change the prompt that is displayed, then include it here. See async_update_prompt() docstring for guidance on updating a prompt. :raises RuntimeError: if called from the main thread. :raises RuntimeError: if called while another thread holds `terminal_lock` """ if threading.current_thread() is threading.main_thread(): raise RuntimeError("async_alert should not be called from the main thread") if not (vt100_support and self.use_rawinput): return # Sanity check that can't fail if self.terminal_lock was acquired before calling this function if self.terminal_lock.acquire(blocking=False): # Windows terminals tend to flicker when we redraw the prompt and input lines. # To reduce how often this occurs, only update terminal if there are changes. update_terminal = False if alert_msg: alert_msg += '\n' update_terminal = True if new_prompt is not None: self.prompt = new_prompt # Check if the onscreen prompt needs to be refreshed to match self.prompt. if self.need_prompt_refresh(): update_terminal = True rl_set_prompt(self.prompt) if update_terminal: import shutil # Prior to Python 3.11 this can return 0, so use a fallback if needed. terminal_columns = shutil.get_terminal_size().columns or constants.DEFAULT_TERMINAL_WIDTH # Print a string which replaces the onscreen prompt and input lines with the alert. terminal_str = ansi.async_alert_str( terminal_columns=terminal_columns, prompt=rl_get_display_prompt(), line=readline.get_line_buffer(), cursor_offset=rl_get_point(), alert_msg=alert_msg, ) if rl_type == RlType.GNU: sys.stderr.write(terminal_str) sys.stderr.flush() elif rl_type == RlType.PYREADLINE: readline.rl.mode.console.write(terminal_str) # Redraw the prompt and input lines below the alert rl_force_redisplay() self.terminal_lock.release() else: raise RuntimeError("another thread holds terminal_lock") def async_update_prompt(self, new_prompt: str) -> None: # pragma: no cover """ Update the command line prompt while the user is still typing at it. This is good for alerting the user to system changes dynamically in between commands. For instance you could alter the color of the prompt to indicate a system status or increase a counter to report an event. If you do alter the actual text of the prompt, it is best to keep the prompt the same width as what's on screen. Otherwise the user's input text will be shifted and the update will not be seamless. If user is at a continuation prompt while entering a multiline command, the onscreen prompt will not change. However, self.prompt will still be updated and display immediately after the multiline line command completes. :param new_prompt: what to change the prompt to :raises RuntimeError: if called from the main thread. :raises RuntimeError: if called while another thread holds `terminal_lock` """ self.async_alert('', new_prompt) def async_refresh_prompt(self) -> None: # pragma: no cover """ Refresh the oncreen prompt to match self.prompt. One case where the onscreen prompt and self.prompt can get out of sync is when async_alert() is called while a user is in search mode (e.g. Ctrl-r). To prevent overwriting readline's onscreen search prompt, self.prompt is updated but readline's saved prompt isn't. Therefore when a user aborts a search, the old prompt is still on screen until they press Enter or this method is called. Call need_prompt_refresh() in an async print thread to know when a refresh is needed. :raises RuntimeError: if called from the main thread. :raises RuntimeError: if called while another thread holds `terminal_lock` """ self.async_alert('') def need_prompt_refresh(self) -> bool: # pragma: no cover """Check whether the onscreen prompt needs to be asynchronously refreshed to match self.prompt.""" if not (vt100_support and self.use_rawinput): return False # Don't overwrite a readline search prompt or a continuation prompt. return not rl_in_search_mode() and not self._at_continuation_prompt and self.prompt != rl_get_prompt() @staticmethod def set_window_title(title: str) -> None: # pragma: no cover """ Set the terminal window title. NOTE: This function writes to stderr. Therefore, if you call this during a command run by a pyscript, the string which updates the title will appear in that command's CommandResult.stderr data. :param title: the new window title """ if not vt100_support: return try: sys.stderr.write(ansi.set_title(title)) sys.stderr.flush() except AttributeError: # Debugging in Pycharm has issues with setting terminal title pass def enable_command(self, command: str) -> None: """ Enable a command by restoring its functions :param command: the command being enabled """ # If the commands is already enabled, then return if command not in self.disabled_commands: return cmd_func_name = constants.COMMAND_FUNC_PREFIX + command help_func_name = constants.HELP_FUNC_PREFIX + command completer_func_name = constants.COMPLETER_FUNC_PREFIX + command # Restore the command function to its original value dc = self.disabled_commands[command] setattr(self, cmd_func_name, dc.command_function) # Restore the help function to its original value if dc.help_function is None: delattr(self, help_func_name) else: setattr(self, help_func_name, dc.help_function) # Restore the completer function to its original value if dc.completer_function is None: delattr(self, completer_func_name) else: setattr(self, completer_func_name, dc.completer_function) # Remove the disabled command entry del self.disabled_commands[command] def enable_category(self, category: str) -> None: """ Enable an entire category of commands :param category: the category to enable """ for cmd_name in list(self.disabled_commands): func = self.disabled_commands[cmd_name].command_function if getattr(func, constants.CMD_ATTR_HELP_CATEGORY, None) == category: self.enable_command(cmd_name) def disable_command(self, command: str, message_to_print: str) -> None: """ Disable a command and overwrite its functions :param command: the command being disabled :param message_to_print: what to print when this command is run or help is called on it while disabled The variable cmd2.COMMAND_NAME can be used as a placeholder for the name of the command being disabled. ex: message_to_print = f"{cmd2.COMMAND_NAME} is currently disabled" """ # If the commands is already disabled, then return if command in self.disabled_commands: return # Make sure this is an actual command command_function = self.cmd_func(command) if command_function is None: raise AttributeError(f"'{command}' does not refer to a command") cmd_func_name = constants.COMMAND_FUNC_PREFIX + command help_func_name = constants.HELP_FUNC_PREFIX + command completer_func_name = constants.COMPLETER_FUNC_PREFIX + command # Add the disabled command record self.disabled_commands[command] = DisabledCommand( command_function=command_function, help_function=getattr(self, help_func_name, None), completer_function=getattr(self, completer_func_name, None), ) # Overwrite the command and help functions to print the message new_func = functools.partial( self._report_disabled_command_usage, message_to_print=message_to_print.replace(constants.COMMAND_NAME, command) ) setattr(self, cmd_func_name, new_func) setattr(self, help_func_name, new_func) # Set the completer to a function that returns a blank list setattr(self, completer_func_name, lambda *args, **kwargs: []) def disable_category(self, category: str, message_to_print: str) -> None: """Disable an entire category of commands. :param category: the category to disable :param message_to_print: what to print when anything in this category is run or help is called on it while disabled. The variable cmd2.COMMAND_NAME can be used as a placeholder for the name of the command being disabled. ex: message_to_print = f"{cmd2.COMMAND_NAME} is currently disabled" """ all_commands = self.get_all_commands() for cmd_name in all_commands: func = self.cmd_func(cmd_name) if getattr(func, constants.CMD_ATTR_HELP_CATEGORY, None) == category: self.disable_command(cmd_name, message_to_print) def _report_disabled_command_usage(self, *_args: Any, message_to_print: str, **_kwargs: Any) -> None: """ Report when a disabled command has been run or had help called on it :param args: not used :param message_to_print: the message reporting that the command is disabled :param kwargs: not used """ # Set apply_style to False so message_to_print's style is not overridden self.perror(message_to_print, apply_style=False) def cmdloop(self, intro: Optional[str] = None) -> int: # type: ignore[override] """This is an outer wrapper around _cmdloop() which deals with extra features provided by cmd2. _cmdloop() provides the main loop equivalent to cmd.cmdloop(). This is a wrapper around that which deals with the following extra features provided by cmd2: - transcript testing - intro banner - exit code :param intro: if provided this overrides self.intro and serves as the intro banner printed once at start """ # cmdloop() expects to be run in the main thread to support extensive use of KeyboardInterrupts throughout the # other built-in functions. You are free to override cmdloop, but much of cmd2's features will be limited. if threading.current_thread() is not threading.main_thread(): raise RuntimeError("cmdloop must be run in the main thread") # Register signal handlers import signal original_sigint_handler = signal.getsignal(signal.SIGINT) signal.signal(signal.SIGINT, self.sigint_handler) if not sys.platform.startswith('win'): original_sighup_handler = signal.getsignal(signal.SIGHUP) signal.signal(signal.SIGHUP, self.termination_signal_handler) original_sigterm_handler = signal.getsignal(signal.SIGTERM) signal.signal(signal.SIGTERM, self.termination_signal_handler) # Grab terminal lock before the command line prompt has been drawn by readline self.terminal_lock.acquire() # Always run the preloop first for func in self._preloop_hooks: func() self.preloop() # If transcript-based regression testing was requested, then do that instead of the main loop if self._transcript_files is not None: self._run_transcript_tests([os.path.expanduser(tf) for tf in self._transcript_files]) else: # If an intro was supplied in the method call, allow it to override the default if intro is not None: self.intro = intro # Print the intro, if there is one, right after the preloop if self.intro is not None: self.poutput(self.intro) # And then call _cmdloop() to enter the main loop self._cmdloop() # Run the postloop() no matter what for func in self._postloop_hooks: func() self.postloop() # Release terminal lock now that postloop code should have stopped any terminal updater threads # This will also zero the lock count in case cmdloop() is called again self.terminal_lock.release() # Restore original signal handlers signal.signal(signal.SIGINT, original_sigint_handler) if not sys.platform.startswith('win'): signal.signal(signal.SIGHUP, original_sighup_handler) signal.signal(signal.SIGTERM, original_sigterm_handler) return self.exit_code ### # # plugin related functions # ### def _initialize_plugin_system(self) -> None: """Initialize the plugin system""" self._preloop_hooks: List[Callable[[], None]] = [] self._postloop_hooks: List[Callable[[], None]] = [] self._postparsing_hooks: List[Callable[[plugin.PostparsingData], plugin.PostparsingData]] = [] self._precmd_hooks: List[Callable[[plugin.PrecommandData], plugin.PrecommandData]] = [] self._postcmd_hooks: List[Callable[[plugin.PostcommandData], plugin.PostcommandData]] = [] self._cmdfinalization_hooks: List[Callable[[plugin.CommandFinalizationData], plugin.CommandFinalizationData]] = [] @classmethod def _validate_callable_param_count(cls, func: Callable[..., Any], count: int) -> None: """Ensure a function has the given number of parameters.""" signature = inspect.signature(func) # validate that the callable has the right number of parameters nparam = len(signature.parameters) if nparam != count: plural = '' if nparam == 1 else 's' raise TypeError(f'{func.__name__} has {nparam} positional argument{plural}, expected {count}') @classmethod def _validate_prepostloop_callable(cls, func: Callable[[], None]) -> None: """Check parameter and return types for preloop and postloop hooks.""" cls._validate_callable_param_count(func, 0) # make sure there is no return notation signature = inspect.signature(func) if signature.return_annotation is not None: raise TypeError(f"{func.__name__} must declare return a return type of 'None'") def register_preloop_hook(self, func: Callable[[], None]) -> None: """Register a function to be called at the beginning of the command loop.""" self._validate_prepostloop_callable(func) self._preloop_hooks.append(func) def register_postloop_hook(self, func: Callable[[], None]) -> None: """Register a function to be called at the end of the command loop.""" self._validate_prepostloop_callable(func) self._postloop_hooks.append(func) @classmethod def _validate_postparsing_callable(cls, func: Callable[[plugin.PostparsingData], plugin.PostparsingData]) -> None: """Check parameter and return types for postparsing hooks""" cls._validate_callable_param_count(cast(Callable[..., Any], func), 1) signature = inspect.signature(func) _, param = list(signature.parameters.items())[0] if param.annotation != plugin.PostparsingData: raise TypeError(f"{func.__name__} must have one parameter declared with type 'cmd2.plugin.PostparsingData'") if signature.return_annotation != plugin.PostparsingData: raise TypeError(f"{func.__name__} must declare return a return type of 'cmd2.plugin.PostparsingData'") def register_postparsing_hook(self, func: Callable[[plugin.PostparsingData], plugin.PostparsingData]) -> None: """Register a function to be called after parsing user input but before running the command""" self._validate_postparsing_callable(func) self._postparsing_hooks.append(func) CommandDataType = TypeVar('CommandDataType') @classmethod def _validate_prepostcmd_hook( cls, func: Callable[[CommandDataType], CommandDataType], data_type: Type[CommandDataType] ) -> None: """Check parameter and return types for pre and post command hooks.""" signature = inspect.signature(func) # validate that the callable has the right number of parameters cls._validate_callable_param_count(cast(Callable[..., Any], func), 1) # validate the parameter has the right annotation paramname = list(signature.parameters.keys())[0] param = signature.parameters[paramname] if param.annotation != data_type: raise TypeError(f'argument 1 of {func.__name__} has incompatible type {param.annotation}, expected {data_type}') # validate the return value has the right annotation if signature.return_annotation == signature.empty: raise TypeError(f'{func.__name__} does not have a declared return type, expected {data_type}') if signature.return_annotation != data_type: raise TypeError( f'{func.__name__} has incompatible return type {signature.return_annotation}, expected ' f'{data_type}' ) def register_precmd_hook(self, func: Callable[[plugin.PrecommandData], plugin.PrecommandData]) -> None: """Register a hook to be called before the command function.""" self._validate_prepostcmd_hook(func, plugin.PrecommandData) self._precmd_hooks.append(func) def register_postcmd_hook(self, func: Callable[[plugin.PostcommandData], plugin.PostcommandData]) -> None: """Register a hook to be called after the command function.""" self._validate_prepostcmd_hook(func, plugin.PostcommandData) self._postcmd_hooks.append(func) @classmethod def _validate_cmdfinalization_callable( cls, func: Callable[[plugin.CommandFinalizationData], plugin.CommandFinalizationData] ) -> None: """Check parameter and return types for command finalization hooks.""" cls._validate_callable_param_count(func, 1) signature = inspect.signature(func) _, param = list(signature.parameters.items())[0] if param.annotation != plugin.CommandFinalizationData: raise TypeError(f"{func.__name__} must have one parameter declared with type {plugin.CommandFinalizationData}") if signature.return_annotation != plugin.CommandFinalizationData: raise TypeError("{func.__name__} must declare return a return type of {plugin.CommandFinalizationData}") def register_cmdfinalization_hook( self, func: Callable[[plugin.CommandFinalizationData], plugin.CommandFinalizationData] ) -> None: """Register a hook to be called after a command is completed, whether it completes successfully or not.""" self._validate_cmdfinalization_callable(func) self._cmdfinalization_hooks.append(func) def _resolve_func_self( self, cmd_support_func: Callable[..., Any], cmd_self: Union[CommandSet, 'Cmd', None], ) -> Optional[object]: """ Attempt to resolve a candidate instance to pass as 'self' for an unbound class method that was used when defining command's argparse object. Since we restrict registration to only a single CommandSet instance of each type, using type is a reasonably safe way to resolve the correct object instance :param cmd_support_func: command support function. This could be a completer or namespace provider :param cmd_self: The `self` associated with the command or subcommand """ # figure out what class the command support function was defined in func_class: Optional[Type[Any]] = get_defining_class(cmd_support_func) # Was there a defining class identified? If so, is it a sub-class of CommandSet? if func_class is not None and issubclass(func_class, CommandSet): # Since the support function is provided as an unbound function, we need to locate the instance # of the CommandSet to pass in as `self` to emulate a bound method call. # We're searching for candidates that match the support function's defining class type in this order: # 1. Is the command's CommandSet a sub-class of the support function's class? # 2. Do any of the registered CommandSets in the Cmd2 application exactly match the type? # 3. Is there a registered CommandSet that is is the only matching subclass? func_self: Optional[Union[CommandSet, 'Cmd']] # check if the command's CommandSet is a sub-class of the support function's defining class if isinstance(cmd_self, func_class): # Case 1: Command's CommandSet is a sub-class of the support function's CommandSet func_self = cmd_self else: # Search all registered CommandSets func_self = None candidate_sets: List[CommandSet] = [] for installed_cmd_set in self._installed_command_sets: if type(installed_cmd_set) == func_class: # noqa: E721 # Case 2: CommandSet is an exact type match for the function's CommandSet func_self = installed_cmd_set break # Add candidate for Case 3: if isinstance(installed_cmd_set, func_class): candidate_sets.append(installed_cmd_set) if func_self is None and len(candidate_sets) == 1: # Case 3: There exists exactly 1 CommandSet that is a sub-class match of the function's CommandSet func_self = candidate_sets[0] return func_self else: return self