bug#65797: `buffer-match-p` should not use `func-arity`

[Joseph Turner]

Dmitry Gutov <dmitry@gutov.dev> writes:

> On 19/09/2023 16:56, Philip Kaludercic wrote:
>> Dmitry Gutov<dmitry@gutov.dev>  writes:
>>
>>> On 19/09/2023 11:34, Philip Kaludercic wrote:
>>>>> [ BTW, changing the code to use `&rest args` instead of `&optional arg`
>>>>>     would help for this, right?  ]
>>>> How come?
>>> In project.el buffer-match-p would be called without an extra
>>> argument, so the predicates would be called without an extra argument
>>> as well.
>>>
>>> That should take care of that compatibility, I think.
>> But what does that have to do with &rest vs &optional?
>
> Stringly speaking, nothing, because you can manage the same scheme
> with &optional - just dispatching to pred with different number of
> arguments depending on whether the &optional arg is nil. Though that
> breaks a little when nil is a meaningful value (probably a rare case).
>
> Rewriting the function in terms of &rest just makes this solution the
> most natural one, I suppose.

I am in favor of this solution as well.

> Though we'll still have to document the distinction in the docstrings
> of project-kill-buffer-conditions and etc (the number of the arguments
> called with).

How do the project.el docstrings need to be updated?

Thank you!

Joseph