help-follow-symbol now complains if no symbol found (bug#38248)

* lisp/help-mode.el (help-follow-symbol): Signal 'user-error' if
there's no symbol at POS.

* etc/NEWS: Document it.

2 files changed, 9 insertions, 4 deletions

diff --git a/etc/NEWS b/etc/NEWS
index b92fdeb6757..ad349b1613a 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -2588,6 +2588,10 @@ pointer is over.  To change this behaviour, you can customize the user
 option 'mouse-wheel-follow-mouse'.  Note that this will also affect
 scrolling.
 
+---
+** help-follow-symbol now signals 'user-error' if point (or the
+position pointed to by the argument POS) is not in a symbol.
+
 
 * Lisp Changes in Emacs 27.1
 
diff --git a/lisp/help-mode.el b/lisp/help-mode.el
index 054a1ef8c24..e70570c3eed 100644
--- a/lisp/help-mode.el
+++ b/lisp/help-mode.el
@@ -749,10 +749,11 @@ Show all docs for that symbol as either a variable, function or face."
             (buffer-substring (point)
                               (progn (skip-syntax-forward "w_")
                                      (point)))))))
-    (when (or (boundp sym)
-              (get sym 'variable-documentation)
-              (fboundp sym) (facep sym))
-      (help-do-xref pos #'describe-symbol (list sym)))))
+    (if (or (boundp sym)
+            (get sym 'variable-documentation)
+            (fboundp sym) (facep sym))
+        (help-do-xref pos #'describe-symbol (list sym))
+      (user-error "No symbol here"))))
 
 (defun help-mode-revert-buffer (_ignore-auto noconfirm)
   (when (or noconfirm (yes-or-no-p "Revert help buffer? "))