# File lib/chef/mixin/why_run.rb, line 166
          def failure_message(*args)
            case args.size
            when 1
              @failure_message = args[0]
            when 2
              @exception_type, @failure_message = args[0], args[1]
            else
              raise ArgumentError, "#{self.class}#failure_message takes 1 or 2 arguments, you gave #{args.inspect}"
            end
          end