Bug report

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

A fix could be to add if 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

from typing import ForwardRef
from typing import TypeVarTuple

Ts = TypeVarTuple("Ts")
typ = ForwardRef("*Ts")._evaluate({}, {"Ts": Ts}, frozenset())
assert typ == next(iter(Ts))  # <-- PASSES AS EXPECTED

typ = ForwardRef("*tuple[int]")._evaluate({}, {}, frozenset())
assert typ == tuple[int]  # <-- PASSES BUT SHOULDN'T
assert typ == next(iter(tuple[int]))  # <-- SHOULD PASS BUT DOESN'T

Your environment

Python 3.11

Linked PRs

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