| #!/usr/bin/env python3 |
| # |
| # Copyright 2023 The Fuchsia Authors |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); |
| # you may not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| |
| from enum import Enum |
| from typing import Type, TypeVar |
| |
| T = TypeVar("T", bound="StrEnum") |
| |
| |
| class StrEnum(str, Enum): |
| def __str__(self) -> str: |
| if not isinstance(self.value, str): |
| raise TypeError(f"Expected a str, got {type(self.value)}") |
| return self.value |
| |
| @classmethod |
| def all(cls: Type[T]) -> list[T]: |
| return [e for e in cls] |
| |
| @classmethod |
| def from_str(cls: Type[T], s: str) -> T: |
| lookup_table = {mode.value: mode for mode in cls.all()} |
| if s in lookup_table: |
| return lookup_table[s] |
| raise TypeError(f'Unknown {cls.__name__} string "{s}"') |
