false positive with divmod and overloaded __divmod__ #9835
Description
from typing import Self, overload
class A:
@overload
def __divmod__(self, x: Self, /) -> tuple[Self, Self]: ...
@overload
def __divmod__(self, x: int, /) -> tuple[int, int]: ...
def __divmod__(self, x: Self | int, /) -> tuple[Self, Self] | tuple[int, int]:
return (self, self) if isinstance(x, A) else (x, x)
reveal_type(divmod(A(), 1))reports two errors:
No overloads for "divmod" match the provided arguments (reportCallIssue)
Argument of type "Literal[1]" cannot be assigned to parameter "y" of type "SupportsRDivMod[_T_contra@divmod, _T_co@divmod]" in function "divmod"
"Literal[1]" is incompatible with protocol "SupportsRDivMod[A, _T_co@divmod]"
"__rdivmod__" is an incompatible type
Type "(value: int, /) -> tuple[int, int]" is not assignable to type "(other: _T_contra@SupportsRDivMod, /) -> _T_co@SupportsRDivMod"
Parameter 1: type "_T_contra@SupportsRDivMod" is incompatible with type "int"
"A" is not assignable to "int" (reportArgumentType)
mypy behaves correctly, and reports:
revealed type is "tuple[builtins.int, builtins.int]"