[PATCH] Improve find-sibling-rules option type

[Paul W. Rankin]

* lisp/files.el (find-sibling-rules): use alist with tags for custom
  type
---
This is preferable than having to enter a sexp as a user option.


 lisp/files.el | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lisp/files.el b/lisp/files.el
index 9d76668..e7adccd 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -7572,7 +7572,8 @@ files, you could say something like:
 In this example, if you're in \"src/emacs/emacs-27/lisp/abbrev.el\",
 and a \"src/emacs/emacs-28/lisp/abbrev.el\" file exists, it's now
 defined as a sibling."
-  :type 'sexp
+  :type '(alist :key-type (string :tag "Match")
+                :value-type (string :tag "Expansion"))
   :version "29.1")
 
 (defun find-sibling-file (file)
-- 
2.42.0