[CHORE] Add trailing comma to multiline elements

[genedan]

There are several places in the code where multiline elements do not have a trailing comma, e.g.,

my_list = [
    'a',
    'b',
    'c',
    'd
]

What Ruff format will do is put them all on the same line. The initial author who wrote the multiline code probably intended for it to stay that way and simply forgot the trailing comma, so we should add them, e.g.,

my_list = [
    'a',
    'b',
    'c',
    'd,
]

While rule COM812 enforces the comma, it interferes with the formatter, so shouldn't be used.

We'll need to use another tool. One can probably make quick work of this issue with an LLM.

[henrydingliu]

ruff format already checks for this. please double check and close if satisfied

[genedan]

For my own code, there are several places where I intentionally make lists multiline even when it doesn't hit the line limit, for readability, alphabetizing, and commenting on specific elements.

This issue might just be limited to me, I just need to go back in and put the trailing commas on my own lines.

[henrydingliu]

well, this is why we didn't adopt a formatter for a very long time, because personal preference eventually gets involved. you either let go of your personal preference, or we discard the formatter as a repo. it can't be a thing where we have a formatter but reviewers insist on their personal formatting preferences anyway. i.e. the only acceptable resolution to this ticket, beside closing, is removing the formatter.

[kennethshsu]

I like using commas too, even on the last element. It does make commenting things easier, it also looks nicer (imo). And I agree that we shouldn't have COM812. This currently works as is no?

• No comma after the last element: if list fits on the same line, it will be consolidated by ruff
• Comma on the last element: stays as a multiline list by ruff