Backport: xref--next-error-function: Move xref's window point

* lisp/progmodes/xref.el (xref--next-error-function): Move
xref's window point if it's visible.  When we don't do that,
navigation can start looping after a while.

(cherry picked from commit 108ce84432d597f92637ea74bd0a094224d157de)

1 files changed, 4 insertions, 0 deletions

diff --git a/lisp/progmodes/xref.el b/lisp/progmodes/xref.el
index e0f5b2d3670..b0bdd62ae98 100644
--- a/lisp/progmodes/xref.el
+++ b/lisp/progmodes/xref.el
@@ -692,6 +692,10 @@ references displayed in the current *xref* buffer."
     (dotimes (_ n)
       (setq xref (xref--search-property 'xref-item backward)))
     (cond (xref
+           ;; Save the current position (when the buffer is visible,
+           ;; it gets reset to that window's point from time to time).
+           (let ((win (get-buffer-window (current-buffer))))
+             (and win (set-window-point win (point))))
            (xref--show-location (xref-item-location xref) t))
           (t
            (error "No %s xref" (if backward "previous" "next"))))))