IMPORTANT

The pre-commit hooks are reverting my work-around for the "ty" issue, even with an attempted work around for the pre-commit issue. Rather than adding yet another work-around, I'm going to see what the maintainers suggest.

Summary

Replaces #1495 (I renamed my branch, which closed the draft PR.)

The optional validator (attrs.validators.optional) should accept any tuple of validators, just as it accepts any list of validators. It looks like the peculiar type annotation syntax for variable-length tuples (tuple[<type>, ...]) was overlooked, and the exactly-one-element form (tuple[<type>]) was inadvertently used instead.

The proposed change corrects the annotation.

Pull Request Check List

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• (N/A) Added tests for changed code.
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• Changes or additions to public APIs are reflected in our type stubs (files ending in .pyi).
  • ...and used in the stub test file typing-examples/baseline.py or, if necessary, typing-examples/mypy.py.
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    The next version is the second number in the current release + 1.
    The first number represents the current year.
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    If the next version is the first in the new year, it'll be 23.1.0.
    • If something changed that affects both attrs.define() and attr.s(), you have to add version directives to both.
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