search for: sender_has_invit

...ipient_email, :token, :sent_at belongs_to :sender, :class_name => ''User'' has_one :recipient, :class_name => ''User'' ###validation validates_presence_of :recipient_email validate :recipient_is_not_registered validate :sender_has_invitations, :if => :sender before_create :generate_token before_create :decrement_sender_count, :if => :sender private def recipient_is_not_registered errors.add :recipient_email, ''Is already registered'' if User.find_by_email(recipient_email) end...