bug#64089: 30.0.50; `ldap-search' errors out with `wrong-type-argument listp' when called WITHDN == t

[Filipp Gunbin <fgunbin@fastmail.fm>]

On 19/06/2023 20:24 +0300, Eli Zaretskii wrote:

>> From: Filipp Gunbin <fgunbin@fastmail.fm>
>> Cc: 64089@debbugs.gnu.org,  jschmidt4gnu@vodafonemail.de,
>>   monnier@iro.umontreal.ca
>> Date: Mon, 19 Jun 2023 17:27:05 +0300
>> 
>> On 18/06/2023 08:22 +0300, Eli Zaretskii wrote:
>> 
>> >> Date: Sun, 18 Jun 2023 02:14:31 +0300
>> >> From: "Filipp Gunbin" <fgunbin@fastmail.fm>
>> >> Cc: 64089@debbugs.gnu.org, monnier@iro.umontreal.ca
>> >> 
>> >> Thanks, but the problem is that
>> >> 
>> >> - the code before the fix prepended dn as string (and it's not
>> >> totally broken - you can skip attribute translation via
>> >> var/defcustom, in which case the error should not be triggered)
>> >> - the fix on emacs-29 now prepends it as cons cell
>> >> - my change on master will again use string form
>> >> 
>> >> So I'd prefer that we leave that unfixed on emacs-29 instead of
>> >> creating this mess.. Or correct cons cell -> string, if it's worth
>> >> the trouble.
>> >
>> > Sorry, I don't understand why we'd like to leave it unfixed.  Please
>> > elaborate.  In particular, it is entirely legitimate for master to
>> > have a different solution.
>> 
>> Hi Eli, this is what I meant:
>> 
>> Previously ldap-search withdn=t returned:
>> 
>> (("<dn value>" ("mail" "...")))
>> 
>> But now it will return:
>> 
>> ((("dn" "<dn value>") ("mail" "...")))
>
> In which situations will the current code cause trouble, where the
> original code didn't?

The above formats are what ldap-search returns when given withdn=t.

Emacs codebase doesn't use withdn=t at all, but ldap-search is a "public"
API function, and we're not supposed to change its return format?