decorator_perf.rb

require "benchmark"
require "delegate"
require "forwardable"

class Person
  def initialize(name, ip)
    @name = name
    @ip = ip
  end

  def name
    @name
  end

  def ip
    @ip
  end

  def to_hash
    {
      name: name,
      ip: ip,
    }
  end
end

class PersonDelegator < SimpleDelegator
  def initialize(person)
    super(person)
  end
end

class PersonForwarder
  extend Forwardable

  def_delegator :@person, :name
  def_delegator :@person, :ip

  def initialize(person)
    @person = person
  end
end

class PersonCopy
  def initialize(person)
    attributes = person.to_hash
    person.public_methods(false).each do |method_name|
      define_singleton_method(method_name) { attributes[method_name] }
    end
  end
end

class PersonMissing
  def method_missing(method_name)
    if @person.respond_to?(method_name)
      @person.send(method_name)
    else
      super
    end
  end

  def initialize(person)
    @person = person
  end
end

bob = Person.new("Bob", "1.2.3.4")

Benchmark.bmbm do |bm|
  bm.report("Sending message directly") do
    1_000_000.times do
      bob.name
    end
  end

  bm.report "Sending message through SimpleDelegator" do
    1_000_000.times do
      PersonDelegator.new(bob).name
    end
  end

  bm.report "Forwarding message using Forwardable" do
    1_000_000.times do
      PersonForwarder.new(bob).name
    end
  end

  bm.report "Forwarding message using define_singleton_method" do
    1_000_000.times do
      PersonCopy.new(bob).name
    end
  end

  bm.report "Sending message using method_missing" do
    1_000_000.times do
      PersonMissing.new(bob).name
    end
  end
end