bug#60285: xref-query-replace-in-results could show an arrow pointing to the current item being replaced

[Juri Linkov]

>> Indeed, there is a special hook for such cases:
>> 'replace-update-post-hook'.
>
> That one seems problematic. First of all, I think (?) that we need to
> update the arrow's position when the replacement prompt appears, not after
> a replacement.

Maybe another pre-hook is needed that will run before the prompt?

> Second, it fires in all cases -- whether the replacement is going forward,
> or it being undone, is that right? I suppose this will mean we'll need to
> maintain a reverse mapping: from the markers back to the Xref buffer
> lines. Hopefully they will be in expected position after the "undo" actions
> too.

This needs more experimentation to see how it works.