bug#66567: [PATCH] use-package: Add ignored-files support to :vc keyword

[Tony Zorman via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

On Wed, Nov 01 2023 09:09, Philip Kaludercic wrote:
>> diff --git a/lisp/use-package/use-package-core.el b/lisp/use-package/use-package-core.el
>> index 34c45b7aec..5d0d554baf 100644
>> --- a/lisp/use-package/use-package-core.el
>> +++ b/lisp/use-package/use-package-core.el
>> @@ -1654,7 +1654,8 @@ use-package-normalize--vc-arg
>>                               (t (ensure-string v))))
>>                   (:vc-backend (ensure-symbol v))
>>                   (_ (ensure-string v)))))
>> -    (pcase-let ((valid-kws '(:url :branch :lisp-dir :main-file :vc-backend :rev))
>> +    (pcase-let ((valid-kws '( :url :branch :lisp-dir :main-file :vc-backend :rev
>> +                              :shell-command :make))
>
> Why is use-package checking for valid keywords in the first place?

Better error messages, mostly. Especially people switching from
quelpa/straight/vc-use-package might be surprised that :vc is not a
drop-in replacement for those packages. I feel like alerting them to
this fact sooner rather than later makes for a better experience.

>> * lisp/use-package/use-package-core.el (use-package-split-when):
>> New utility function to split a list whenever a specified predicate
>> returns t.
>> (use-package-vc-valid-keywords): A new defconst to gather all allowed
>> keywords.
>> (use-package-normalize--vc-arg): Properly normalize the :ignored-files
>> keyword, in that the following are all valid ways of entering files:
>>   :ignored-files "a"
>>   :ignored-files ("a")
>>   :ignored-files "a" "b" "c"
>>   :ignored-files ("a" "b" "c")
>> (use-package-normalize/:vc): Adjust normalization, now that we do not
>> necessarily receive a valid plist as an input.
>
> I would much prefer that package specifications have a canonical form
> and that use-package doesn't try to introduce variations that wouldn't
> be compatible with package-vc-install proper and elpa-admin.  Or is this
> necessary for use-package?

It's not *necessary*, but it's quite common for use-package keywords to
do their best in order to be as unobtrusive as possible. This includes
omitting parentheses that might not be strictly needed, or to cleverly
transform the input in some other way (e.g., :hook makes great use of
this).

>> I will cheekily bump this, and also Cc. Philip as the most likely
>> reviewer.
>
> I don't use use-package nor am I familiar with the code base, so I
> wouldn't value my input that much.

Oh, fair enough. In either case, I couldn't think of anyone else—sorry
for the noise :)

-- 
Tony Zorman | https://tony-zorman.com/