Single line with binary operator in commented list causes additional line breaks #4026

Describe the bug

Inside a list, a comment followed by a single line with division operator causes additional lines breaks before each division operator.

To Reproduce

For example, take this code:

import pathlib

foobar = [
    # comment
    pathlib.Path("foo") / "bar" / "baz",
]

fizzbuzz = [
    # comment
    23 / 7
]

And run black on it with the default config.

The resulting formatted code is:

import pathlib

foobar = [
    # comment
    pathlib.Path("foo")
    / "bar"
    / "baz",
]

fizzbuzz = [
    # comment
    23
    / 7
]

Expected behavior

The formatting doesn't change (apart from maybe the trailing comma).

Environment

• Black's version: 23.10.1 (compiled: yes)
• OS and Python version: Fedora Linux 38 / Python 3.11.6

Additional context

Formatting does not occur if the expression is enclosed in parentheses, e.g.

(pathlib.Path("foo") / "bar" / "baz")

It also doesn't happen any more once additional lines are introduced to the lists.