stdlib: fix signatures for some functions with unrepresentable defaults

[JelleZijlstra]

Found with python/mypy#16433

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉

[AlexWaygood]

These all look correct.

I pick up 14 more errors running stdlib stubtest locally on Python 3.12 with a Windows machine with your stubtest PR branch -- you could do those as well? But I'm also happy to defer those to another PR

Additional errors

error: _warnings.warn is inconsistent, stub does not have argument "skip_file_prefixes"
Stub: in file stdlib\_warnings.pyi:7
Overload(def (message: builtins.str, category: Union[Type[builtins.Warning], None] =, stacklevel: builtins.int =, source: Union[Any, None] =), def (message: builtins.Warning, category: Any =, stacklevel: builtins.int =, source: Union[Any, None] =))
Inferred signature: def (message: Union[builtins.str, builtins.Warning], category: Union[Type[builtins.Warning], None, Any] = ..., stacklevel: builtins.int = ..., source: Union[Any, None] = ...)
Runtime:
def (message, category=None, stacklevel=1, source=None, *, skip_file_prefixes=<unrepresentable>)

error: builtins.getattr is inconsistent, stub argument "__name" has a default value but runtime argument does not
Stub: in file stdlib\builtins.pyi:1426
Overload(def (builtins.object, builtins.str) -> Any, def (builtins.object, builtins.str, None) -> Union[Any, None], def (builtins.object, builtins.str, builtins.bool) -> Union[Any, builtins.bool], def (builtins.object, name: builtins.str, builtins.list[Any]) -> Union[Any, builtins.list[Any]], def (builtins.object, name: builtins.str, builtins.dict[Any, Any]) -> Union[Any, builtins.dict[Any, Any]], def [_T] (builtins.object, builtins.str, _T`-1) -> Union[Any, _T`-1])
Inferred signature: def (__o: builtins.object, __name: builtins.str = ..., name: builtins.str = ..., __default: Union[None, builtins.bool, builtins.list[Any], builtins.dict[Any, Any], _T`-1] = ...)
Runtime:
def (object, name, default=<unrepresentable>, /)

error: builtins.getattr is inconsistent, stub argument "name" differs from runtime argument "default"
Stub: in file stdlib\builtins.pyi:1426
Overload(def (builtins.object, builtins.str) -> Any, def (builtins.object, builtins.str, None) -> Union[Any, None], def (builtins.object, builtins.str, builtins.bool) -> Union[Any, builtins.bool], def (builtins.object, name: builtins.str, builtins.list[Any]) -> Union[Any, builtins.list[Any]], def (builtins.object, name: builtins.str, builtins.dict[Any, Any]) -> Union[Any, builtins.dict[Any, Any]], def [_T] (builtins.object, builtins.str, _T`-1) -> Union[Any, _T`-1])
Inferred signature: def (__o: builtins.object, __name: builtins.str = ..., name: builtins.str = ..., __default: Union[None, builtins.bool, builtins.list[Any], builtins.dict[Any, Any], _T`-1] = ...)
Runtime:
def (object, name, default=<unrepresentable>, /)

error: builtins.getattr is inconsistent, stub argument "name" should be positional-only (rename with a leading double underscore, i.e. "__default")
Stub: in file stdlib\builtins.pyi:1426
Overload(def (builtins.object, builtins.str) -> Any, def (builtins.object, builtins.str, None) -> Union[Any, None], def (builtins.object, builtins.str, builtins.bool) -> Union[Any, builtins.bool], def (builtins.object, name: builtins.str, builtins.list[Any]) -> Union[Any, builtins.list[Any]], def (builtins.object, name: builtins.str, builtins.dict[Any, Any]) -> Union[Any, builtins.dict[Any, Any]], def [_T] (builtins.object, builtins.str, _T`-1) -> Union[Any, _T`-1])
Inferred signature: def (__o: builtins.object, __name: builtins.str = ..., name: builtins.str = ..., __default: Union[None, builtins.bool, builtins.list[Any], builtins.dict[Any, Any], _T`-1] = ...)
Runtime:
def (object, name, default=<unrepresentable>, /)

error: builtins.getattr is inconsistent, runtime does not have argument "__default"
Stub: in file stdlib\builtins.pyi:1426
Overload(def (builtins.object, builtins.str) -> Any, def (builtins.object, builtins.str, None) -> Union[Any, None], def (builtins.object, builtins.str, builtins.bool) -> Union[Any, builtins.bool], def (builtins.object, name: builtins.str, builtins.list[Any]) -> Union[Any, builtins.list[Any]], def (builtins.object, name: builtins.str, builtins.dict[Any, Any]) -> Union[Any, builtins.dict[Any, Any]], def [_T] (builtins.object, builtins.str, _T`-1) -> Union[Any, _T`-1])
Inferred signature: def (__o: builtins.object, __name: builtins.str = ..., name: builtins.str = ..., __default: Union[None, builtins.bool, builtins.list[Any], builtins.dict[Any, Any], _T`-1] = ...)
Runtime:
def (object, name, default=<unrepresentable>, /)

error: builtins.iter is inconsistent, stub argument "__iterable" differs from runtime argument "object"
Stub: in file stdlib\builtins.pyi:1453
Overload(def [_SupportsNextT <: _typeshed.SupportsNext[Any]] (_typeshed.SupportsIter[_SupportsNextT`-1]) -> _SupportsNextT`-1, def [_T] (builtins._GetItemIterable[_T`-1]) -> typing.Iterator[_T`-1], def [_T] (def () -> Union[_T`-1, None], None) -> typing.Iterator[_T`-1], def [_T] (def () -> _T`-1, builtins.object) -> typing.Iterator[_T`-1])
Inferred signature: def (__iterable: Union[_typeshed.SupportsIter[_SupportsNextT`-1], builtins._GetItemIterable[_T`-1], def () -> Union[_T`-1, None]], __sentinel: builtins.object = ...)
Runtime:
def (object, sentinel=<unrepresentable>, /)

error: codecs.StreamReader.__getattr__ is inconsistent, runtime argument "getattr" has a default value of type def (Any, Any, Any =) -> Any, which is incompatible with stub argument type def (builtins.str) -> Any
Stub: in file stdlib\codecs.pyi:230
def (codecs.StreamReader, builtins.str, def (builtins.str) -> Any =) -> Any
Runtime: in file <frozen codecs>
def (self, name, getattr=<built-in function getattr>)

error: codecs.StreamWriter.__getattr__ is inconsistent, runtime argument "getattr" has a default value of type def (Any, Any, Any =) -> Any, which is incompatible with stub argument type def (builtins.str) -> Any
Stub: in file stdlib\codecs.pyi:216
def (codecs.StreamWriter, builtins.str, def (builtins.str) -> Any =) -> Any
Runtime: in file <frozen codecs>
def (self, name, getattr=<built-in function getattr>)

error: collections.OrderedDict.pop is inconsistent, stub argument "__key" should be positional or keyword (remove leading double underscore)
Stub: in file stdlib\collections\__init__.pyi:1106
Overload(def (self: builtins.dict[_KT`1, _VT`2], _KT`1) -> _VT`2, def (self: builtins.dict[_KT`1, _VT`2], _KT`1, _VT`2) -> _VT`2, def [_T] (self: builtins.dict[_KT`1, _VT`2], _KT`1, _T`-1) -> Union[_VT`2, _T`-1])
Inferred signature: def (self: builtins.dict[_KT`1, _VT`2], __key: _KT`1, __default: Union[_VT`2, _T`-1] = ...)
Runtime:
def (self, /, key, default=<unrepresentable>)

error: collections.OrderedDict.pop is inconsistent, stub argument "__default" should be positional or keyword (remove leading double underscore)
Stub: in file stdlib\collections\__init__.pyi:1106
Overload(def (self: builtins.dict[_KT`1, _VT`2], _KT`1) -> _VT`2, def (self: builtins.dict[_KT`1, _VT`2], _KT`1, _VT`2) -> _VT`2, def [_T] (self: builtins.dict[_KT`1, _VT`2], _KT`1, _T`-1) -> Union[_VT`2, _T`-1])
Inferred signature: def (self: builtins.dict[_KT`1, _VT`2], __key: _KT`1, __default: Union[_VT`2, _T`-1] = ...)
Runtime:
def (self, /, key, default=<unrepresentable>)

error: contextvars.ContextVar.get is inconsistent, stub argument "default" should be positional-only (rename with a leading double underscore, i.e. "__default")
Stub: in file stdlib\contextvars.pyi:24
Overload(def (self: contextvars.ContextVar[_T`1]) -> _T`1, def (self: contextvars.ContextVar[_T`1], default: _T`1) -> _T`1, def [_D] (self: contextvars.ContextVar[_T`1], default: _D`-1) -> Union[_D`-1, _T`1])
Inferred signature: def (self: contextvars.ContextVar[_T`1], default: Union[_T`1, _D`-1] = ...)
Runtime:
def (self, default=<unrepresentable>, /)

error: sqlite3.Connection.cursor is inconsistent, stub argument "cursorClass" differs from runtime argument "factory"
Stub: in file stdlib\sqlite3\__init__.pyi:351
Overload(def (self: sqlite3.dbapi2.Connection, cursorClass: None =) -> sqlite3.dbapi2.Cursor, def [_CursorT <: sqlite3.dbapi2.Cursor] (self: sqlite3.dbapi2.Connection, cursorClass: def (sqlite3.dbapi2.Connection) -> _CursorT`-1) -> _CursorT`-1)
Inferred signature: def (self: sqlite3.dbapi2.Connection, cursorClass: Union[None, def (sqlite3.dbapi2.Connection) -> _CursorT`-1] = ...)
Runtime:
def (self, /, factory=<unrepresentable>)

error: sqlite3.dbapi2.Connection.cursor is inconsistent, stub argument "cursorClass" differs from runtime argument "factory"
Stub: in file stdlib\sqlite3\dbapi2.pyi:351
Overload(def (self: sqlite3.dbapi2.Connection, cursorClass: None =) -> sqlite3.dbapi2.Cursor, def [_CursorT <: sqlite3.dbapi2.Cursor] (self: sqlite3.dbapi2.Connection, cursorClass: def (sqlite3.dbapi2.Connection) -> _CursorT`-1) -> _CursorT`-1)
Inferred signature: def (self: sqlite3.dbapi2.Connection, cursorClass: Union[None, def (sqlite3.dbapi2.Connection) -> _CursorT`-1] = ...)
Runtime:
def (self, /, factory=<unrepresentable>)

error: warnings.warn is inconsistent, stub does not have argument "skip_file_prefixes"
Stub: in file stdlib\warnings.pyi:7
Overload(def (message: builtins.str, category: Union[Type[builtins.Warning], None] =, stacklevel: builtins.int =, source: Union[Any, None] =), def (message: builtins.Warning, category: Any =, stacklevel: builtins.int =, source: Union[Any, None] =))
Inferred signature: def (message: Union[builtins.str, builtins.Warning], category: Union[Type[builtins.Warning], None, Any] = ..., stacklevel: builtins.int = ..., source: Union[Any, None] = ...)
Runtime:
def (message, category=None, stacklevel=1, source=None, *, skip_file_prefixes=<unrepresentable>)

Found 14 errors (checked 726 modules)

[JelleZijlstra]

I was planning to point stubtest at my branch in a separate PR so I could see the fallout across versions and OSes.

Also the getattr() error in your output looks like a bug.

[AlexWaygood]

Also the getattr() error in your output looks like a bug.

yes