Added song

lib/model/song.rb

@@ -0,0 +1,17 @@
+module Rhythmic
+  class Song
+
+    def initialize
+      @playables = []
+    end
+
+    def add(playable)
+      @playables.push playable
+    end
+
+    def play
+      @playables.each {|playable| playable.play}
+
+    end
+  end
+end

rhythmic.rb

@@ -9,6 +9,7 @@
 require "./lib/model/drumkit_loader_yaml"
 require "./lib/model/drumkit"
 require "./lib/model/sample"
+require "./lib/model/song"
 
 if defined?(Rubygame::Sound).nil?
   puts "Couldn't load SDL and SDL_Mixer. Are they correcly installed?. Please check https://github.com/rafadc/rythmic for installation instructions."

spec/song_spec.rb

@@ -0,0 +1,17 @@
+require "rspec"
+
+require_relative("../rhythmic")
+
+describe "Song playing" do
+
+  it "should play a drumkit and a loop if added to a song" do
+    drumkit = double("Drumkit")
+    loop = double("Loop")
+    song = Rhythmic::Song.new
+    song.add drumkit
+    song.add loop
+    drumkit.should_receive(:play)
+    loop.should_receive(:play)
+    song.play
+  end
+end