image-dired: Mark 'per-directory' as :safe

* lisp/image/image-dired.el (image-dired-thumbnail-storage): Mark
'per-directory' value as :safe.

diff --git a/lisp/image/image-dired.el b/lisp/image/image-dired.el
index 07c76a2a1ffb58bc1f5db2584345042697421a76..d84734f4d4656beb53f0f1914a8bfce7941c33cd 100644 (file)
--- a/lisp/image/image-dired.el
+++ b/lisp/image/image-dired.el
@@ -209,6 +209,7 @@ https://specifications.freedesktop.org/thumbnail-spec/thumbnail-spec-latest.html
                  (const :tag "Thumbnail Managing Standard (extra large 1024x1024)"
                         standard-xx-large)
                  (const :tag "Per-directory" per-directory))
+  :safe (lambda (value) (eq value 'per-directory))
   :version "29.1")
 
 (define-obsolete-variable-alias 'image-dired-db-file