Indent in ruby

indent-partial.el

;;
;; Permits to indent like that :
;; class Comment < ActiveRecord::Base
;;   after_create :send_email_to_author,
;;                :if => :author_wants_emails?,
;;                :unless => Proc.new { |comment| comment.post.ignore_comments? }
;; end
;;

(defadvice ruby-indent-line (after line-up-args activate)
  (let (indent prev-indent arg-indent)
    (save-excursion
      (back-to-indentation)
      (when (zerop (car (syntax-ppss)))
        (setq indent (current-column))
        (skip-chars-backward " \t\n")
        (when (eq ?, (char-before))
          (ruby-backward-sexp)
          (back-to-indentation)
          (setq prev-indent (current-column))
          (skip-syntax-forward "w_.")
          (skip-chars-forward " ")
          (setq arg-indent (current-column)))))
    (when prev-indent
      (let ((offset (- (current-column) indent)))
        (cond ((< indent prev-indent)
               (indent-line-to prev-indent))
              ((= indent prev-indent)
               (indent-line-to arg-indent)))
        (when (> offset 0) (forward-char offset))))))