# Copyright 2012-2023, Andrey Kislyuk and argcomplete contributors.
# Licensed under the Apache License. See https://github.com/kislyuk/argcomplete for more info.
import argparse
import os
import subprocess
from collections.abc import Callable, Generator, Iterable, Mapping
from shlex import quote
from typing import Final
_Ignored = object
def _call(*args, **kwargs):
# TODO: replace "universal_newlines" with "text" once 3.6 support is dropped
kwargs["universal_newlines"] = True
try:
return subprocess.check_output(*args, **kwargs).splitlines()
except subprocess.CalledProcessError:
return []
class BaseCompleter:
"""
This is the base class that all argcomplete completers should subclass.
"""
def __call__(
self, *, prefix: str, action: argparse.Action, parser: argparse.ArgumentParser, parsed_args: argparse.Namespace
) -> Iterable[str]:
raise NotImplementedError("This method should be implemented by a subclass.")
[docs]
class ChoicesCompleter(BaseCompleter):
choices: Final[Mapping[str, str | bytes]]
[docs]
def __init__(self, choices: Mapping[str, str | bytes]) -> None:
self.choices = choices
def _convert(self, choice):
if not isinstance(choice, str):
choice = str(choice)
return choice
[docs]
def __call__(self, **kwargs: _Ignored) -> Iterable[str]:
return (self._convert(c) for c in self.choices)
EnvironCompleter: Final[ChoicesCompleter] = ChoicesCompleter(os.environ)
[docs]
class FilesCompleter(BaseCompleter):
"""
File completer class, optionally takes a list of allowed extensions
"""
allowednames: Final[list[str]]
directories: Final[bool]
[docs]
def __init__(self, allowednames: Iterable[str] | str = (), directories: bool = True) -> None:
# Fix if someone passes in a string instead of a list
if isinstance(allowednames, (str, bytes)):
allowednames = [allowednames]
self.allowednames = [x.lstrip("*").lstrip(".") for x in allowednames]
self.directories = directories
[docs]
def __call__(self, prefix: str, **kwargs: _Ignored) -> list[str]:
completion: list[str] = []
if self.allowednames:
if self.directories:
# Using 'bind' in this and the following commands is a workaround to a bug in bash
# that was fixed in bash 5.3 but affects older versions. Environment variables are not treated
# correctly in older versions and calling bind makes them available. For details, see
# https://savannah.gnu.org/support/index.php?111125
files = _call(
["bash", "-c", "bind; compgen -A directory -- {p}".format(p=quote(prefix))],
stderr=subprocess.DEVNULL,
)
completion += [f + "/" for f in files]
for x in self.allowednames:
completion += _call(
["bash", "-c", "bind; compgen -A file -X '!*.{0}' -- {p}".format(x, p=quote(prefix))],
stderr=subprocess.DEVNULL,
)
else:
completion += _call(
["bash", "-c", "bind; compgen -A file -- {p}".format(p=quote(prefix))], stderr=subprocess.DEVNULL
)
anticomp = _call(
["bash", "-c", "bind; compgen -A directory -- {p}".format(p=quote(prefix))],
stderr=subprocess.DEVNULL,
)
completion = list(set(completion) - set(anticomp))
if self.directories:
completion += [f + "/" for f in anticomp]
return completion
class _FilteredFilesCompleter(BaseCompleter):
predicate: Final[Callable[[str], bool]]
def __init__(self, predicate: Callable[[str], bool]) -> None:
"""
Create the completer
A predicate accepts as its only argument a candidate path and either
accepts it or rejects it.
"""
assert predicate, "Expected a callable predicate" # type: ignore[truthy-function]
self.predicate = predicate
def __call__(self, prefix: str, **kwargs: _Ignored) -> Generator[str]:
"""
Provide completions on prefix
"""
# Expand a leading "~" so that filesystem operations below work on a
# real path (os.listdir("~") would otherwise raise FileNotFoundError).
expanded_prefix = os.path.expanduser(prefix)
target_dir = os.path.dirname(expanded_prefix)
try:
names = os.listdir(target_dir or ".")
except Exception:
return # empty iterator
incomplete_part = os.path.basename(expanded_prefix)
# Iterate on target_dir entries and filter on given predicate
for name in names:
if not name.startswith(incomplete_part):
continue
candidate = os.path.join(target_dir, name)
if not self.predicate(candidate):
continue
yield candidate + "/" if os.path.isdir(candidate) else candidate
[docs]
class DirectoriesCompleter(_FilteredFilesCompleter):
[docs]
def __init__(self) -> None:
_FilteredFilesCompleter.__init__(self, predicate=os.path.isdir)
[docs]
class SuppressCompleter(BaseCompleter):
"""
A completer used to suppress the completion of specific arguments
"""
[docs]
def __init__(self) -> None:
pass
[docs]
def suppress(self) -> bool:
"""
Decide if the completion should be suppressed
"""
return True