Support ParamSpec for TypeAliasType #449
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| self.assertEqual(get_args(callable_concat), (Concatenate[int, P],)) | ||
| concat_usage = callable_concat[str] | ||
| self.assertEqual(get_args(concat_usage), ((int, str),)) | ||
| self.assertEqual(concat_usage, callable_concat[[str]]) |
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Should this block be removed? This is more about GenericAlias usage here and how Concatenate/Unpack is handled.
I think the self.assertEqual(concat_usage, callable_concat[[str]]) test is interesting, but I am not sure about the specifications if this should be valid and stay here.
See also the test_invalid_cases tests where this is redone with a TypeVar.
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Since using types.GenericAlias these tests became much clearer. Given that Concatenate might need some special treatmeant in TypeAliasType.__getitem__ (currently done by isinstance(param, list)) and this is the only test where this is looked into with a bit more detail, I think it should probaly stay.
AlexWaygood
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AlexWaygood
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I haven't looked deeply at the changes in this PR yet (will do so either today or tomorrow), but here's some comments from skimming through:
Related to: python/cpython#124787
minor comment corrections
| return self.__name__ | ||
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| if sys.version_info < (3, 11): | ||
| def _check_single_param(self, param, recursion=0): |
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Doesn't seem like this needs to be a generator, it always yields a single value. Let's make it return that value instead and simplify _check_parameters.
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Looking at it again. As the current cpython implementation does not not seems to use _type_convert or any restrictions, should we just drop all checks here?
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Changes in #489 are necessary to remove _check_parameters / _type_convert. More specifically, _ConcatenateGenericAlias needs _copy_with and __getitem__ if it is not converted to a list via the above functions to be handled correctly in 3.8 & 3.9.
| with self.subTest("get_args of Concatenate in TypeAliasType"): | ||
| if not TYPING_3_9_0: | ||
| # args are: ([<class 'int'>, ~P2],) | ||
| self.skipTest("Nested ParamSpec is not substituted") |
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Fixes #448 that usage of ParamSpec with TypeAliasType was limited for < Python 3.11
This PR enables
TypeAliasTypeto use Ellipsis and list arguments forParamSpectype params.