Add lexical cookie to new init files

* lisp/cus-edit.el (custom-save-all):
Add lexical cookie if the file is empty.

(cherry picked from commit 2f5c9b31161306b2b4c46c77c351c6ea6a46ff98)

diff --git a/lisp/cus-edit.el b/lisp/cus-edit.el
index 32cfef6bae48a1eba6fdf9a75a2aa96cb7131c93..e94c7fa2376e08269486c2db555d4da31e074c64 100644 (file)
--- a/lisp/cus-edit.el
+++ b/lisp/cus-edit.el
@@ -4996,6 +4996,8 @@ if only the first line of the docstring is shown."))
             ;; readably.  (Bug#52554)
             (print-escape-control-characters t))
         (atomic-change-group
+          (when (eobp)
+            (insert ";;; -*- lexical-binding: t -*-\n"))
          (custom-save-variables)
          (custom-save-faces)
           (custom-save-icons)))