OpenHome/venv/Lib/site-packages/pip/_internal/cli/command_context.py

31 lines
815 B
Python
Raw Permalink Normal View History

2021-07-21 21:33:05 +02:00
from contextlib import ExitStack, contextmanager
from typing import ContextManager, Iterator, TypeVar
_T = TypeVar("_T", covariant=True)
class CommandContextMixIn:
def __init__(self):
# type: () -> None
super().__init__()
self._in_main_context = False
self._main_context = ExitStack()
@contextmanager
def main_context(self):
# type: () -> Iterator[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):
# type: (ContextManager[_T]) -> _T
assert self._in_main_context
return self._main_context.enter_context(context_provider)