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bpo-46553: allow bare typing.ClassVar annotations (#30983) · python/cpython@5445e17

3 files changed

lines changed

Original file line numberDiff line numberDiff line change

@@ -2071,7 +2071,7 @@ def test_fail_with_bare_union(self):

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with self.assertRaises(TypeError):

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Tuple[Optional]

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with self.assertRaises(TypeError):

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ClassVar[ClassVar]

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ClassVar[ClassVar[int]]

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with self.assertRaises(TypeError):

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List[ClassVar[int]]

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@@ -2896,12 +2896,16 @@ def test_special_forms_forward(self):

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class C:

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a: Annotated['ClassVar[int]', (3, 5)] = 4

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b: Annotated['Final[int]', "const"] = 4

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x: 'ClassVar' = 4

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y: 'Final' = 4

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class CF:

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b: List['Final[int]'] = 4

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self.assertEqual(get_type_hints(C, globals())['a'], ClassVar[int])

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self.assertEqual(get_type_hints(C, globals())['b'], Final[int])

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self.assertEqual(get_type_hints(C, globals())['x'], ClassVar)

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self.assertEqual(get_type_hints(C, globals())['y'], Final)

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with self.assertRaises(TypeError):

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get_type_hints(CF, globals()),

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Original file line numberDiff line numberDiff line change

@@ -173,7 +173,7 @@ def _type_check(arg, msg, is_argument=True, module=None, *, allow_special_forms=

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if (isinstance(arg, _GenericAlias) and

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arg.__origin__ in invalid_generic_forms):

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raise TypeError(f"{arg} is not valid as type argument")

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if arg in (Any, NoReturn, Final):

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if arg in (Any, NoReturn, ClassVar, Final):

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return arg

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if isinstance(arg, _SpecialForm) or arg in (Generic, Protocol):

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raise TypeError(f"Plain {arg} is not valid as type argument")

Original file line numberDiff line numberDiff line change

@@ -0,0 +1 @@

1+

In :func:`typing.get_type_hints`, support evaluating bare stringified ``ClassVar`` annotations. Patch by Gregory Beauregard.