active_model_serializers/lib/active_model/serializer/config.rb

module ActiveModel
  class Serializer
    class Config
      def initialize
        @data = {}
      end

      def [](key)
        @data[key.to_s]
      end

      def []=(key, value)
        @data[key.to_s] = value
      end

      def each(&block)
        @data.each(&block)
      end

      def clear
        @data.clear
      end

      def method_missing(name, *args)
        name = name.to_s
        return @data[name] if @data.include?(name)
        match = name.match(/\A(.*?)([?=]?)\Z/)
        case match[2]
        when "="
          @data[match[1]] = args.first
        when "?"
          !!@data[match[1]]
        end
      end
    end

    CONFIG = Config.new
  end
end