(require 'ert)

(ert-deftest undo-after-revert-buffer ()
  (should-not
   (unwind-protect
       (progn
         (find-file "simple-file.txt")
         (goto-char (point-min))
         (insert "\n")
         (revert-buffer t t)
         (undo-auto--needs-boundary-p))
     (kill-buffer
      (get-file-buffer
       "simple-file.txt")))))