codekingpro/portable-devtools

1"""2Basic Flag and Flags data structures.3"""4from __future__ import annotations5 6from collections.abc import Iterable, Iterator, MutableSet7from typing import NamedTuple8 9 10class Flag(NamedTuple):11    name: str12    bit: int13 14 15class Flags(MutableSet):  # type: ignore16    """17    A simple MutableSet implementation that will only accept known flags as18    elements.19 20    Will behave like a regular set(), except that a ValueError will be thrown21    when .add()ing unexpected flags.22    """23 24    def __init__(self, defined_flags: Iterable[Flag]) -> None:25        self._valid_flags = {flag.name for flag in defined_flags}26        self._flags: set[str] = set()27 28    def __repr__(self) -> str:29        return repr(sorted(self._flags))30 31    def __contains__(self, x: object) -> bool:32        return self._flags.__contains__(x)33 34    def __iter__(self) -> Iterator[str]:35        return self._flags.__iter__()36 37    def __len__(self) -> int:38        return self._flags.__len__()39 40    def discard(self, value: str) -> None:41        return self._flags.discard(value)42 43    def add(self, value: str) -> None:44        if value not in self._valid_flags:45            msg = f"Unexpected flag: {value}. Valid flags are: {self._valid_flags}"46            raise ValueError(msg)47        return self._flags.add(value)48