Rule idea: check for complex function type annotations

[tjkuson]

It would be nice to have a lint rule that checks for convoluted type annotations, similar to rules that check for complicated functions.

The recommendation would be to move the type information to a type alias or to create a new data type (such as a NamedTuple) to refactor type information.

I don't have a specific idea about how the rule should measure type complexity (it could involve measuring nesting, unions, or just the number of parameters); I am more interested in checking if there would be an appetite for any such rule in Ruff at the moment!

[strmwalker]

There is a rule in wemake-python-styleguide https://wemake-python-styleguide.readthedocs.io/en/latest/pages/usage/violations/complexity.html#wemake_python_styleguide.violations.complexity.TooComplexAnnotationViolation
You can take a look at #3845

[AlexWaygood]

Thanks for the feature request! I'm going to close this in favour of #2323, as it seems like basically the same idea to me (happy to reopen if I'm mistaken!)