Bug report

Unpack information oftyping.GenericAlias is not transferred from string annotations to interpreted annotations.typing.Unpacked works as expected.

A fix could be to addif getattr(t, "__unpacked__", False): return next(iter(GenericAlias(t.__origin__, ev_args))) clause here:

NOTE: This bug is in typing's internal API and I don't think there's issues in the public API (but haven't looked hard). However, this issue pops up quickly if you try to do anything wrt PEP 646 typing at runtime.

Minimal example

fromtypingimportForwardReffromtypingimportTypeVarTupleTs=TypeVarTuple("Ts")typ=ForwardRef("*Ts")._evaluate({}, {"Ts":Ts},frozenset())asserttyp==next(iter(Ts))# <-- PASSES AS EXPECTEDtyp=ForwardRef("*tuple[int]")._evaluate({}, {},frozenset())asserttyp==tuple[int]# <-- PASSES BUT SHOULDN'Tasserttyp==next(iter(tuple[int]))# <-- SHOULD PASS BUT DOESN'T

Your environment

Python 3.11

Linked PRs

• gh-101015: Fixtyping.get_type_hints with unpacked*tuple (PEP 646) #101031
• [3.11] gh-101015: Fixtyping.get_type_hints with unpacked*tuple (PEP 646) (GH-101031) #101254