bug#58158: 29.0.50; [overlay] Interval tree iteration considered harmful

[Dmitry Gutov]

On 07.10.2022 22:47, Eli Zaretskii wrote:
> > Date: Fri, 7 Oct 2022 01:36:17 +0300
> > Cc: 58158@debbugs.gnu.org, monnier@iro.umontreal.ca
> > From: Dmitry Gutov <dgutov@yandex.ru>
> >
> > On 30.09.2022 09:11, Eli Zaretskii wrote:
> > > "M-x xref-query-replace-in-results RET"
> >
> > JFYI this command has the convenient binding 'r' in Xref output buffers.
>
> It also works only when invoked from the Xref buffer, right?

Yep.

But we also have commands like xref-find-references-and-replace and 
dired-do-find-regexp-and-replace.

> Btw, what am I doing wrong below?
>
>   emacs -Q
>   C-x C-f src/character.h RET
>   M-x visit-tags-table RET RET
>   M-. char_string RET
>   r whatever RET
>
> Unexpected result: "No suitable matches here".  Huh? what did I miss?

We can't replace over "find definition" matches: they are more abstract 
and don't contain the necessary information to perform the replacement 
(such as the length of a match, for instance).

And such xrefs might navigate you to the beginning of the line, for 
example, rather than to the beginning of the name.

But that makes sense, doesn't it? If replacing over "find definitions" 
results worked fine, in the end you would get a codebase where all 
declarations of a method 'foo' got renamed, but all callsites of it 
remain unchanged. That couldn't have been your intention, could it?

The error message could use some improvement, I suppose, but I'm not 
sure how to make it better.