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