Little helper for GNU Emacs to "karma run"

karma-compile.el

(require 'ansi-color)
(defvar karma-buffer
  "*karma-node-specs-buffer*")

(defun karma-compile ()
  "Run Karma"
  (interactive)
  (shell-command "karma run" (get-buffer-create karma-buffer))
  (display-buffer karma-buffer)
  (with-current-buffer karma-buffer
    (ansi-color-apply-on-region (point-min) (point-max))
    (save-excursion
      (while (re-search-forward "^.*\n\\[1A\\[2K" nil t)
	(replace-match "" nil nil)
      (beginning-of-buffer)))))

;; bind to key (M-r) in js-mode, adapt to your liking
(add-hook 'js-mode-hook
          (lambda ()
	    (local-set-key (kbd "M-r") 'karma-compile)))