毎回rakeの前にバッファをキルする変更

gistfile1.el

(defun motion-execute-rake-command ()
  (let* ((use-bundler (motion-bundler-p))
         (buf (let ((buffer-name (concat "*" motion-execute-rake-buffer "*")))
                (when (get-buffer buffer-name)
                  (let ((kill-buffer-query-functions nil))
                    (kill-buffer buffer-name)))
                (get-buffer-create buffer-name)))
         (sub-command (motion-get-rake-sub-command use-bundler))
         (params (motion-construct-rake-command use-bundler sub-command)))
    (message "%s" (mapconcat (lambda (p) (if p (concat p " ") "")) params ""))
    (apply 'make-comint motion-execute-rake-buffer params)
    (pop-to-buffer buf)))