diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py index 58781e52aca6d8..703fe84f3aad10 100644 --- a/Lib/test/test_typing.py +++ b/Lib/test/test_typing.py @@ -978,6 +978,38 @@ def foo(**kwargs: Unpack[Movie]): ... self.assertEqual(repr(foo.__annotations__['kwargs']), f"typing.Unpack[{__name__}.Movie]") + def test_builtin_tuple(self): + Ts = TypeVarTuple("Ts") + + class Old(Generic[*Ts]): ... + class New[*Ts]: ... + + PartOld = Old[int, *Ts] + self.assertEqual(PartOld[str].__args__, (int, str)) + self.assertEqual(PartOld[*tuple[str]].__args__, (int, str)) + self.assertEqual(PartOld[*Tuple[str]].__args__, (int, str)) + self.assertEqual(PartOld[Unpack[tuple[str]]].__args__, (int, str)) + self.assertEqual(PartOld[Unpack[Tuple[str]]].__args__, (int, str)) + + PartNew = New[int, *Ts] + self.assertEqual(PartNew[str].__args__, (int, str)) + self.assertEqual(PartNew[*tuple[str]].__args__, (int, str)) + self.assertEqual(PartNew[*Tuple[str]].__args__, (int, str)) + self.assertEqual(PartNew[Unpack[tuple[str]]].__args__, (int, str)) + self.assertEqual(PartNew[Unpack[Tuple[str]]].__args__, (int, str)) + + def test_unpack_wrong_type(self): + Ts = TypeVarTuple("Ts") + class Gen[*Ts]: ... + PartGen = Gen[int, *Ts] + + bad_unpack_param = re.escape("Unpack[...] must be used with a tuple type") + with self.assertRaisesRegex(TypeError, bad_unpack_param): + PartGen[Unpack[list[int]]] + with self.assertRaisesRegex(TypeError, bad_unpack_param): + PartGen[Unpack[List[int]]] + + class TypeVarTupleTests(BaseTestCase): def assertEndsWith(self, string, tail): diff --git a/Lib/typing.py b/Lib/typing.py index a0b68f593ca0d9..b3f4ba99f9ec21 100644 --- a/Lib/typing.py +++ b/Lib/typing.py @@ -1786,8 +1786,9 @@ def __typing_unpacked_tuple_args__(self): assert self.__origin__ is Unpack assert len(self.__args__) == 1 arg, = self.__args__ - if isinstance(arg, _GenericAlias): - assert arg.__origin__ is tuple + if isinstance(arg, (_GenericAlias, types.GenericAlias)): + if arg.__origin__ is not tuple: + raise TypeError("Unpack[...] must be used with a tuple type") return arg.__args__ return None diff --git a/Misc/NEWS.d/next/Library/2024-04-22-20-42-29.gh-issue-118168.Igni7h.rst b/Misc/NEWS.d/next/Library/2024-04-22-20-42-29.gh-issue-118168.Igni7h.rst new file mode 100644 index 00000000000000..78c3e0fe17979a --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-04-22-20-42-29.gh-issue-118168.Igni7h.rst @@ -0,0 +1,4 @@ +Fix incorrect argument substitution when :data:`typing.Unpack` is used with +the builtin :class:`tuple`. :data:`!typing.Unpack` now raises +:exc:`TypeError` when used with certain invalid types. Patch by Jelle +Zijlstra.