| from contextlib import ExitStack, contextmanager |
| from typing import ContextManager, Generator, TypeVar |
| |
| _T = TypeVar("_T", covariant=True) |
| |
| |
| class CommandContextMixIn: |
| def __init__(self) -> None: |
| super().__init__() |
| self._in_main_context = False |
| self._main_context = ExitStack() |
| |
| @contextmanager |
| def main_context(self) -> Generator[None, None, None]: |
| assert not self._in_main_context |
| |
| self._in_main_context = True |
| try: |
| with self._main_context: |
| yield |
| finally: |
| self._in_main_context = False |
| |
| def enter_context(self, context_provider: ContextManager[_T]) -> _T: |
| assert self._in_main_context |
| |
| return self._main_context.enter_context(context_provider) |
