# File lib/whiskey_disk.rb, line 85
    def apply_staleness_check(commands)
      needs(:deploy_to, :repository)
      
      check = "cd #{self[:deploy_to]}; " +
              "ml=\`cat .git/refs/heads/#{branch}\`; " +
              "mr=\`git ls-remote #{self[:repository]} refs/heads/#{branch}\`; "
      
      if self[:deploy_config_to]
        check += "cd #{self[:deploy_config_to]}; " +
                 "cl=\`cat .git/refs/heads/#{config_branch}\`; " +
                 "cr=\`git ls-remote #{self[:config_repository]} refs/heads/#{config_branch}\`; "
      end
      
      check += "if [[ $ml != ${mr%%\t*} ]] " +
               (self[:deploy_config_to] ? "|| [[ $cl != ${cr%%\t*} ]]" : '') +
               "; then #{commands}; else echo \"No changes to deploy.\"; fi"
    end