Ruby Encoder - Strategy Pattern

encoder.rb

class Encoder
  
  def initialize(algorithm)
    @algorithm = algorithm
  end
  
  def encode(line)
    tokens = line.split(" ")
    results = []
    for word in tokens do
      results << @algorithm.encode_word(word)
    end
    results.join(" ")
  end
  
end

class Reverser
  def encode_word(word)
    word.reverse
  end
end

class Doubler 
  def encode_word(word)
    word * 2
  end
end

encoder_spec.rb

require './encoder'

describe Reverser do
  it "reverses each word in the input" do
    encoder = Encoder.new(Reverser.new)
    encoder.encode("abcde 123").should == "edcba 321" 
  end
end

describe Doubler do
  it "doubles each word in the input" do
    encoder = Encoder.new(Doubler.new)
    encoder.encode("abcde 123").should == "abcdeabcde 123123" 
  end
end