Do not allow to use Final and ClassVar at same time #10478
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| from typing import Final, ClassVar | ||
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| class A: | ||
| a: Final[ClassVar[int]] # E: Variable should not be annotated with both ClassVar and Final |
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Can you test some other variants, such as a: ClassVar[Final] = 1, a: ClassVar[Final[int]]?
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Such cases will produce an error with message:
Final can be only used as an outermost qualifier in a variable annotation.
Should it be changed to Variable should not be annotated with both ClassVar and Final?
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If it's easy to do, then yes. The existing error message would make users first swap the qualifiers, then get an error anyway from your new check, which is not very user-friendly. But don't worry about changing the error message if it's complicated.
Either way I think it would be useful to test all these variations here. They can all go in the same test case.
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I have added tests that you mention, thanks for pointing this out.
Looks like it is not easy to change message for a ClassVar[Final[int]] case.
I will skip this for this moment.
This PR allows to use Final and ClassVar after python 3.13 I saw this [PR](#10478) and I saw recent changes of python 3.13 https://docs.python.org/3/library/typing.html#typing.Final Final now can be nested with ClassVar. so I added a version check! --------- Co-authored-by: triumph1 <seungwon.jeong@wesang.com> Co-authored-by: hauntsaninja <hauntsaninja@gmail.com>
Description
Fixes #10477
Do not allow to use Final and ClassVar at same time.
Test Plan
Code bellow:
After this PR will produce an error:
But currently, it will not raise any error.