Fixed incorrect extension management

[lgiordani]

@justinmayer I'm sorry to report that the solution you suggested here does not work. I had to restore the original format of the variable (a list) and add a weird typing to satisfy Ruff.

[justinmayer]

Thank you for letting me know about this. I think see what happened here.

I originally intended to change the assignment to a non-mutable tuple:

file_extensions = ("mau")

… forgetting for a moment that a single-item tuple must have a trailing comma — otherwise it just becomes a string. So when I later ran Black, it dropped the "unnecessary" parentheses, and I didn't notice the change.

In short, unless there is a reason for this value to be mutable, I think perhaps my originally-intended change might be the best solution:

file_extensions = ("mau",)

Would that work?

(Side note: astral-sh/ruff#5243)

[lgiordani]

That makes sense @justinmayer, I didn't think about it, even though it tripped me over multiple times (usually converting values with a comma into tuples, not the other way around). Anyway, have a look if that is OK now. Thanks!

[justinmayer]

Thank you for fixing this!