Use _typeshed.OptExcInfo in pydoc and unittest (#7668)

Author: AlexWaygood

stdlib/pydoc.pyi

@@ -1,17 +1,13 @@
-from _typeshed import SupportsWrite
+from _typeshed import OptExcInfo, SupportsWrite
 from abc import abstractmethod
 from builtins import list as _list  # "list" conflicts with method name
 from collections.abc import Callable, Container, Mapping, MutableMapping
 from reprlib import Repr
 from types import MethodType, ModuleType, TracebackType
 from typing import IO, Any, AnyStr, NoReturn, TypeVar
-from typing_extensions import TypeAlias
 
 __all__ = ["help"]
 
-# the return type of sys.exc_info(), used by ErrorDuringImport.__init__
-_Exc_Info: TypeAlias = tuple[type[BaseException] | None, BaseException | None, TracebackType | None]
-
 _T = TypeVar("_T")
 
 __author__: str
@@ -39,7 +35,7 @@ class ErrorDuringImport(Exception):
     exc: type[BaseException] | None
     value: BaseException | None
     tb: TracebackType | None
-    def __init__(self, filename: str, exc_info: _Exc_Info) -> None: ...
+    def __init__(self, filename: str, exc_info: OptExcInfo) -> None: ...
 
 def importfile(path: str) -> ModuleType: ...
 def safeimport(path: str, forceload: bool = ..., cache: MutableMapping[str, ModuleType] = ...) -> ModuleType: ...

stdlib/unittest/result.pyi

@@ -1,10 +1,7 @@
 import unittest.case
+from _typeshed import OptExcInfo
 from collections.abc import Callable
-from types import TracebackType
-from typing import Any, TextIO, TypeVar, Union
-from typing_extensions import TypeAlias
-
-_SysExcInfoType: TypeAlias = Union[tuple[type[BaseException], BaseException, TracebackType], tuple[None, None, None]]
+from typing import Any, TextIO, TypeVar
 
 _F = TypeVar("_F", bound=Callable[..., Any])
 
@@ -33,10 +30,10 @@ class TestResult:
     def stopTest(self, test: unittest.case.TestCase) -> None: ...
     def startTestRun(self) -> None: ...
     def stopTestRun(self) -> None: ...
-    def addError(self, test: unittest.case.TestCase, err: _SysExcInfoType) -> None: ...
-    def addFailure(self, test: unittest.case.TestCase, err: _SysExcInfoType) -> None: ...
+    def addError(self, test: unittest.case.TestCase, err: OptExcInfo) -> None: ...
+    def addFailure(self, test: unittest.case.TestCase, err: OptExcInfo) -> None: ...
     def addSuccess(self, test: unittest.case.TestCase) -> None: ...
     def addSkip(self, test: unittest.case.TestCase, reason: str) -> None: ...
-    def addExpectedFailure(self, test: unittest.case.TestCase, err: _SysExcInfoType) -> None: ...
+    def addExpectedFailure(self, test: unittest.case.TestCase, err: OptExcInfo) -> None: ...
     def addUnexpectedSuccess(self, test: unittest.case.TestCase) -> None: ...
-    def addSubTest(self, test: unittest.case.TestCase, subtest: unittest.case.TestCase, err: _SysExcInfoType | None) -> None: ...
+    def addSubTest(self, test: unittest.case.TestCase, subtest: unittest.case.TestCase, err: OptExcInfo | None) -> None: ...