Line wrapping on generic functions using the type parameter syntax

[PaulWassermann]

Describe the style change

The suggested style change regards the type parameter syntax introduced in Python 3.12.

When formatting lines too long, I think line-wrapping should occur in the arguments' parenthesis rather than in the type parameters' brackets.

Examples in the current Black style

This would work with any generic function using the new type parameter syntax with a long enough signature (longer than the line-length).

type SupportedDataTypes = float
type Tensor = list

def sum_backward[
T: SupportedDataTypes
](a: Tensor[T], grad: Tensor[T]) -> dict[Tensor[T], Tensor[T]]:
    ...

Desired style

I think this kind of line-wrapping, keeping the type parameters list on a single line when possible, should be preferred over what currently happens as it is more readable.

type SupportedDataTypes = float
type Tensor = list

def sum_backward[T: SupportedDataTypes](
    a: Tensor[T], 
    grad: Tensor[T]
) -> dict[Tensor[T], Tensor[T]]:
    ...

[arre-ankit]

In which section we have to implement this syntax can you give more context about the files where we have to change the syntax ?

[kanugurajesh]

hi can you assign me this issue?

[JelleZijlstra]

We don't generally assign issues. However, PRs are welcome!

[hauntsaninja]

Duplicate of #4071 , PR welcome