Update artist spec.

models/artist.rb

@@ -7,10 +7,6 @@ class Artist
     @name = name
   end
 
-  def <=>(artist)
-    name <=> artist.name
-  end
-
   def self.all
     MPDConnection.mpd.artists.sort.map { |artist| Artist.new(artist) }
   end

spec/models/artist_spec.rb

@@ -3,9 +3,16 @@ require 'spec_helper'
 describe Artist do
 
   let(:artist) { Artist.new('Alice Cooper') }
+  let(:artists) { ['Alice Cooper', 'Jimmy Eat World', 'Dream Theater'] }
 
   it 'has attributes' do
     expect(artist.name).to eq('Alice Cooper')
   end
 
+  it 'returns all artists' do
+    MPDConnection.mpd.stub(:artists).and_return(artists)
+    expect(Artist.all).to have(3).items
+    expect(Artist.all.map(&:name)).to eq(artists.sort)
+  end
+
 end