Contents

module Structure
  def self.included(base)
    base.extend(ClassMethods).instance_variable_set(:@attribute_names, [])
  end

  def attributes
    attribute_names.reduce({}) { |ret, name|
      ret.update(name => self.send(name))
    }
  end

  def attribute_names
    self.class.attribute_names
  end

  def ==(other)
    return false unless other.respond_to?(:attributes)
    attributes == other.attributes
  end

  def inspect
    class_name = self.class.name || self.class.to_s.gsub(/[^\w:]/, '')

    "#<#{class_name} #{
      attributes
        .map { |key, val|
          if val.is_a?(Array) && val.size > 3
            "#{key}=[#{val.take(3).map(&:inspect).join(', ')}...]"
          else
            "#{key}=#{val.inspect}"
          end
        }
        .join(', ')
    }>"
  end

  alias_method :to_h, :attributes
  alias_method :eql?, :==
  alias_method :to_s, :inspect

  module ClassMethods
    attr_reader :attribute_names

    def double(&blk)
      klass = Class.new(self)

      (private_instance_methods(false) + protected_instance_methods(false) - [:initialize])
        .each do |mth|
          klass.send(:undef_method, mth)
        end

      klass.module_eval do
        def initialize(data = {})
          data.each { |key, val| instance_variable_set(:"@#{key}", val.freeze) }
        end

        attribute_names.each do |name|
          module_eval "def _#{name}; @#{name}; end"
          private "_#{name}"
        end

        module_eval(&blk) if block_given?
      end

      klass
    end

    def inherited(subclass)
      subclass.instance_variable_set(:@attribute_names, @attribute_names.dup)
    end

    private

    def attribute(name, &blk)
      name = name.to_s
      module_eval "def #{name}?; #{name}; end" if name.chomp!('?')
      module_eval "def #{name}; @#{name} ||= _#{name}.freeze; end"
      define_method("_#{name}", blk)
      private "_#{name}"

      @attribute_names << name
    end
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
structure-0.28.1	structure.rb