bug#23455: 25.0.93; profiler-report doesn't configure xref for elisp

[Lars Ingebrigtsen <larsi@gnus.org>]

Juliusz Chroboczek <jch@pps.univ-paris-diderot.fr> writes:

> Pressing M-. in the buffer generated by profiler-report prompts me for
> a TAGS file rather than behaving like it does in an elisp buffer.

(I'm going through old Emacs bug reports that haven't received any
response.)

The following patch seems to make `M-.' work as expected in the report
buffers, but I'm wholly unfamiliar with how xref works -- I just
cargo-culted the code in elisp-mode.el.

Perhaps somebody who knows how this works can say whether it looks OK:

diff --git a/lisp/profiler.el b/lisp/profiler.el
index ee11ff68c5..92495e2de8 100644
--- a/lisp/profiler.el
+++ b/lisp/profiler.el
@@ -615,9 +615,12 @@ profiler-report-setup-buffer
       (profiler-report-render-calltree))
     buffer))
 
+(defun profiler--xref-backend () 'elisp)
+
 (define-derived-mode profiler-report-mode special-mode "Profiler-Report"
   "Profiler Report Mode."
   (add-to-invisibility-spec '(profiler . t))
+  (add-hook 'xref-backend-functions #'profiler--xref-backend nil t)
   (setq buffer-read-only t
 	buffer-undo-list t
 	truncate-lines t))

-- 
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   bloggy blog: http://lars.ingebrigtsen.no