+(defun diff-apply-buffer ()
+ "Apply the diff in the entire diff buffer.
+When applying all hunks was successful, then save the changed buffers."
+ (interactive)
+ (let ((buffer-edits nil)
+ (failures 0)
+ (diff-refine nil))
+ (save-excursion
+ (goto-char (point-min))
+ (diff-beginning-of-hunk t)
+ (while (pcase-let ((`(,buf ,line-offset ,pos ,_src ,dst ,switched)
+ (diff-find-source-location nil nil)))
+ (cond ((and line-offset (not switched))
+ (push (cons pos dst)
+ (alist-get buf buffer-edits)))
+ (t (setq failures (1+ failures))))
+ (not (or (eq (prog1 (point) (diff-hunk-next)) (point))
+ (eobp))))))
+ (cond ((zerop failures)
+ (dolist (buf-edits (reverse buffer-edits))
+ (with-current-buffer (car buf-edits)
+ (dolist (edit (cdr buf-edits))
+ (let ((pos (car edit))
+ (dst (cdr edit))
+ (inhibit-read-only t))
+ (goto-char (car pos))
+ (delete-region (car pos) (cdr pos))
+ (insert (car dst))))
+ (save-buffer)))
+ (message "Saved %d buffers" (length buffer-edits)))
+ (t
+ (message "%d hunks failed; no buffers changed" failures)))))