To rename and delete buffer/file

gistfile1.el

(defun rename-this-buffer-and-file ()
  "Renames current buffer and file it is visiting."
  (interactive)
  (let ((name (buffer-name))
        (filename (buffer-file-name)))
    (if (not (and filename (file-exists-p filename)))
        (error "Buffer '%s' is not visiting a file!" name)
      (let ((new-name (read-file-name "New name: " filename)))
        (cond ((get-buffer new-name)
               (error "A buffer named '%s' already exists!" new-name))
              (t
               (rename-file filename new-name 1)
               (rename-buffer new-name)
               (set-visited-file-name new-name)
               (set-buffer-modified-p nil)
               (message "File '%s' successfully renamed to '%s'" name (file-name-nondirectory new-name))))))))

(defun delete-this-buffer-and-file ()
  "Removes file connected to current buffer and kills buffer."
  (interactive)
  (let ((filename (buffer-file-name))
        (buffer (current-buffer))
        (name (buffer-name)))
    (if (not (and filename (file-exists-p filename)))
        (error "Buffer '%s' is not visiting a file!" name)
      (when (yes-or-no-p "Are you sure you want to remove this file? ")
        (delete-file filename)
        (kill-buffer buffer)
        (message "File '%s' successfully removed" filename)))))