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

[Eli Zaretskii]

> From: Filipp Gunbin <fgunbin@fastmail.fm>
> Cc: 64089@debbugs.gnu.org,  jschmidt4gnu@vodafonemail.de,
>   monnier@iro.umontreal.ca
> Date: Mon, 19 Jun 2023 21:38:19 +0300
> 
> On 19/06/2023 20:24 +0300, Eli Zaretskii wrote:
> 
> >> 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?

Where is its return format documented for the withdn=t case?