CS2613/utils/python-venv/Lib/site-packages/exceptiongroup/_exceptions.py

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2022-10-31 10:10:52 -03:00
from __future__ import annotations
from collections.abc import Sequence
from functools import partial
from inspect import getmro, isclass
from typing import Any, Callable, Generic, Tuple, Type, TypeVar, Union, cast
T = TypeVar("T", bound="BaseExceptionGroup")
EBase = TypeVar("EBase", bound=BaseException)
E = TypeVar("E", bound=Exception)
_SplitCondition = Union[
Type[EBase],
Tuple[Type[EBase], ...],
Callable[[EBase], bool],
]
def check_direct_subclass(
exc: BaseException, parents: tuple[type[BaseException]]
) -> bool:
for cls in getmro(exc.__class__)[:-1]:
if cls in parents:
return True
return False
def get_condition_filter(condition: _SplitCondition) -> Callable[[BaseException], bool]:
if isclass(condition) and issubclass(
cast(Type[BaseException], condition), BaseException
):
return partial(check_direct_subclass, parents=(condition,))
elif isinstance(condition, tuple):
if all(isclass(x) and issubclass(x, BaseException) for x in condition):
return partial(check_direct_subclass, parents=condition)
elif callable(condition):
return cast(Callable[[BaseException], bool], condition)
raise TypeError("expected a function, exception type or tuple of exception types")
class BaseExceptionGroup(BaseException, Generic[EBase]):
"""A combination of multiple unrelated exceptions."""
def __new__(
cls, __message: str, __exceptions: Sequence[EBase]
) -> BaseExceptionGroup[EBase] | ExceptionGroup[E]:
if not isinstance(__message, str):
raise TypeError(f"argument 1 must be str, not {type(__message)}")
if not isinstance(__exceptions, Sequence):
raise TypeError("second argument (exceptions) must be a sequence")
if not __exceptions:
raise ValueError(
"second argument (exceptions) must be a non-empty sequence"
)
for i, exc in enumerate(__exceptions):
if not isinstance(exc, BaseException):
raise ValueError(
f"Item {i} of second argument (exceptions) is not an " f"exception"
)
if cls is BaseExceptionGroup:
if all(isinstance(exc, Exception) for exc in __exceptions):
cls = ExceptionGroup
return super().__new__(cls, __message, __exceptions)
def __init__(self, __message: str, __exceptions: Sequence[EBase], *args: Any):
super().__init__(__message, __exceptions, *args)
self._message = __message
self._exceptions = __exceptions
def add_note(self, note: str) -> None:
if not isinstance(note, str):
raise TypeError(
f"Expected a string, got note={note!r} (type {type(note).__name__})"
)
if not hasattr(self, "__notes__"):
self.__notes__: list[str] = []
self.__notes__.append(note)
@property
def message(self) -> str:
return self._message
@property
def exceptions(self) -> tuple[EBase, ...]:
return tuple(self._exceptions)
def subgroup(self: T, __condition: _SplitCondition[EBase]) -> T | None:
condition = get_condition_filter(__condition)
modified = False
if condition(self):
return self
exceptions: list[BaseException] = []
for exc in self.exceptions:
if isinstance(exc, BaseExceptionGroup):
subgroup = exc.subgroup(condition)
if subgroup is not None:
exceptions.append(subgroup)
if subgroup is not exc:
modified = True
elif condition(exc):
exceptions.append(exc)
else:
modified = True
if not modified:
return self
elif exceptions:
group = self.derive(exceptions)
group.__cause__ = self.__cause__
group.__context__ = self.__context__
group.__traceback__ = self.__traceback__
return group
else:
return None
def split(
self: T, __condition: _SplitCondition[EBase]
) -> tuple[T | None, T | None]:
condition = get_condition_filter(__condition)
if condition(self):
return self, None
matching_exceptions: list[BaseException] = []
nonmatching_exceptions: list[BaseException] = []
for exc in self.exceptions:
if isinstance(exc, BaseExceptionGroup):
matching, nonmatching = exc.split(condition)
if matching is not None:
matching_exceptions.append(matching)
if nonmatching is not None:
nonmatching_exceptions.append(nonmatching)
elif condition(exc):
matching_exceptions.append(exc)
else:
nonmatching_exceptions.append(exc)
matching_group: T | None = None
if matching_exceptions:
matching_group = self.derive(matching_exceptions)
matching_group.__cause__ = self.__cause__
matching_group.__context__ = self.__context__
matching_group.__traceback__ = self.__traceback__
nonmatching_group: T | None = None
if nonmatching_exceptions:
nonmatching_group = self.derive(nonmatching_exceptions)
nonmatching_group.__cause__ = self.__cause__
nonmatching_group.__context__ = self.__context__
nonmatching_group.__traceback__ = self.__traceback__
return matching_group, nonmatching_group
def derive(self: T, __excs: Sequence[EBase]) -> T:
eg = BaseExceptionGroup(self.message, __excs)
if hasattr(self, "__notes__"):
# Create a new list so that add_note() only affects one exceptiongroup
eg.__notes__ = list(self.__notes__)
return eg
def __str__(self) -> str:
suffix = "" if len(self._exceptions) == 1 else "s"
return f"{self.message} ({len(self._exceptions)} sub-exception{suffix})"
def __repr__(self) -> str:
return f"{self.__class__.__name__}({self.message!r}, {self._exceptions!r})"
class ExceptionGroup(BaseExceptionGroup[E], Exception, Generic[E]):
def __new__(cls, __message: str, __exceptions: Sequence[E]) -> ExceptionGroup[E]:
instance: ExceptionGroup[E] = super().__new__(cls, __message, __exceptions)
if cls is ExceptionGroup:
for exc in __exceptions:
if not isinstance(exc, Exception):
raise TypeError("Cannot nest BaseExceptions in an ExceptionGroup")
return instance