Python 3.12 def f[T: Generics](...)

[leaver2000]

Describe the style change

I have found the way black is handling inline generics ie def f[T](...) a little unexpected and less consistent with prior style.

Examples in the current Black style

[tool.black]
line-length = 119
target-version = ['py312']

Using non inline generics, the function is split along the arguments, this is expected.

T = TypeVar("T", bound=float)

def function_name(
    x1: datetime.datetime, x2: datetime.datetime, x3: datetime.datetime, dtype: type[T] = float
) -> None: ...

Using python312 inline generics, the function is split within the generics declaration. If you consider the git diff this is a much more substantial change vs the Desired style.

def function_name[
    T: float
](x1: datetime.datetime, x2: datetime.datetime, x3: datetime.datetime, dtype: type[T] = float) -> None: ...

Desired style

Retain the prior style and keep the inline generics inline with the function name

def function_name[T: float](
    x1: datetime.datetime, x2: datetime.datetime, x3: datetime.datetime, dtype: type[T] = float
) -> None: ...

Additional context

There appears to be a bug with trailing comma's?

def function_name[
    T: float
](x1: datetime.datetime, x2: datetime.datetime, x3: datetime.datetime, dtype: type[T] = float,) -> None: ...
# -------------------------------------------------------------------------------------------------^ what about my trailing comma
# would have expected....
def function_name[T: float](
    x1: datetime.datetime, 
    x2: datetime.datetime, 
    x3: datetime.datetime, 
    dtype: type[T] = float,
) -> None: ...

[leaver2000]

# this is case that prompted the Issue
def get[
    T: np.generic
](
    name: Vars = "VIL", *, file: str = "latest", datetime: datetime.datetime | None = None, dtype: type[T] = np.float64
) -> Array[Nd[Y, X], T]:

# save 2 lines of code
def get[T: np.generic](
    name: Vars = "VIL", *, file: str = "latest", datetime: datetime.datetime | None = None, dtype: type[T] = np.float64
) -> Array[Nd[Y, X], T]:

[cobaltt7]

Duplicate of #4254