find_or_create_filter

# File actionpack/lib/action_controller/filters.rb, line 64
        def find_or_create_filter(filter, filter_type, options = {})
          update_filter_in_chain([filter], options)

          if found_filter = find(filter) { |f| f.type == filter_type }
            found_filter
          else
            filter_kind = case
            when filter.respond_to?(:before) && filter_type == :before
              :before
            when filter.respond_to?(:after) && filter_type == :after
              :after
            else
              :filter
            end

            case filter_type
            when :before
              BeforeFilter.new(filter_kind, filter, options)
            when :after
              AfterFilter.new(filter_kind, filter, options)
            else
              AroundFilter.new(filter_kind, filter, options)
            end
          end
        end