bug#37820: 25.2; xref using etags incorrect case fold during completion

[Radey Shouman <shouman@comcast.net>]

Dmitry Gutov writes:
 > On 19.10.2019 9:53, Eli Zaretskii wrote:
 > > Isn't that a contradiction of sorts?  How can we know which of these
 > > two should have precedence?
 > 
 > I think completion-ignore-case should have precedence in this example 
 > because the user called an xref command.
 > 
 > Whether tags are used, or something else, is an implementation detail. 
 > Behavior should be as similar as possible.

I doubt that many users actually set the default value of
completion-ignore-case, it is normally used by binding it during a
completion according to the need of the particular application.

Tags search behavior should follow the documentation and many years of
precedent, regardless of whether xref is the front end.  Case folding
during tags search completion, or any other search completion should
be consistent with the search itself.

If you are proposing to add a variable to control case-folding during all xref
searches, analogous to tags-case-fold-search, then I agree.