# File lib/chef/knife/cookbook_test.rb, line 45
      def run
        config[:cookbook_path] ||= Chef::Config[:cookbook_path]

        checked_a_cookbook = false
        if config[:all]
          cookbook_loader.each do |key, cookbook|
            checked_a_cookbook = true
            test_cookbook(key)
          end
        else
          @name_args.each do |cb|
            puts "checking #{cb}"
            next unless cookbook_loader.cookbook_exists?(cb)
            checked_a_cookbook = true
            test_cookbook(cb)
          end
        end
        unless checked_a_cookbook
          ui.warn("No cookbooks to test in #{Array(config[:cookbook_path]).join(',')} - is your cookbook path misconfigured?")
        end
      end