[Python] Why does black output a different format when code has comments?

Examples 1


python code:

def long_long_long_long_long_long_long_long_long_long_long_long_func(arg: list): ...


long_long_long_long_long_long_long_long_long_long_long_name = (
long_long_long_long_long_long_long_long_long_long_long_long_func(
arg=[
"long_long_long_long_long_long_long_long_long_long_long_string",
"long_long_long_long_long_long_long_long_long_long_long_string",
]
)
)


after black, nothing changed. That's good.

Examples 2


python code:

def long_long_long_long_long_long_long_long_long_long_long_long_func(arg: list): ...


long_long_long_long_long_long_long_long_long_long_long_name = (
long_long_long_long_long_long_long_long_long_long_long_long_func(
arg=[
"long_long_long_long_long_long_long_long_long_long_long_string",
# a comment
"long_long_long_long_long_long_long_long_long_long_long_string",
]
)
)


after black, I got below. This is obviously not what I want.

def long_long_long_long_long_long_long_long_long_long_long_long_func(arg: list): ...


long_long_long_long_long_long_long_long_long_long_long_name = long_long_long_long_long_long_long_long_long_long_long_long_func(
arg=[
"long_long_long_long_long_long_long_long_long_long_long_string",
# a comment
"long_long_long_long_long_long_long_long_long_long_long_string",
]
)

env

• black, 24.8.0 (compiled: yes)
• Python (CPython) 3.9.19
• macOS Sonoma 14.5

what I try

• I've simplified the sample code to the point where it can at least reproduce the problem.
• I looked in Black's documentation for line breaks, maximum length, and there was no explanation for this
• I searched stackoverflow. Com and Google and found no instructions.

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