Fix cloning of eieio-named objects (Bug#22840)

* lisp/emacs-lisp/eieio-base.el (clone): Correctly set the name of the
  cloned objects from eieio-named instances.

1 files changed, 11 insertions, 9 deletions

diff --git a/lisp/emacs-lisp/eieio-base.el b/lisp/emacs-lisp/eieio-base.el
index 7a9f905c6fe..3aeda92db12 100644
--- a/lisp/emacs-lisp/eieio-base.el
+++ b/lisp/emacs-lisp/eieio-base.el
@@ -510,16 +510,18 @@ instance."
 All slots are unbound, except those initialized with PARAMS."
   (let* ((newname (and (stringp (car params)) (pop params)))
          (nobj (apply #'cl-call-next-method obj params))
-         (nm (slot-value obj 'object-name)))
-    (eieio-oset obj 'object-name
+         (nm (slot-value nobj 'object-name)))
+    (eieio-oset nobj 'object-name
                 (or newname
-                    (save-match-data
-                      (if (and nm (string-match "-\\([0-9]+\\)" nm))
-                          (let ((num (1+ (string-to-number
-                                          (match-string 1 nm)))))
-                            (concat (substring nm 0 (match-beginning 0))
-                                    "-" (int-to-string num)))
-                        (concat nm "-1")))))
+                    (if (equal nm (slot-value obj 'object-name))
+                        (save-match-data
+                          (if (and nm (string-match "-\\([0-9]+\\)" nm))
+                              (let ((num (1+ (string-to-number
+                                              (match-string 1 nm)))))
+                                (concat (substring nm 0 (match-beginning 0))
+                                        "-" (int-to-string num)))
+                            (concat nm "-1")))
+                      nm)))
     nobj))
 
 (cl-defmethod make-instance ((class (subclass eieio-named)) &rest args)