title: Rspec uninitialized constant ActiveRecord(NameError)
body: <p>I followed codeschool tutorial, but I encountered some troubles.</p>
  
  <p>Here is <strong>zombie_spec.rb</strong></p>
  
  <pre><code>#spec/model/zombie_spec.rb
  require 'spec_helper'
  require 'zombie'
  
  
  describe Zombie do
  it 'is invalid without a name' do
      zombie = Zombie.new 
      zombie.should_not be_valid
      end     
  end
  </code></pre>
  
  <p><strong>zombie.rb</strong></p>
  
  <pre><code>#spec/zombie.rb
  class Zombie &lt; ActiveRecord::Base 
      validates :name, presence: true
      ...
  end
  </code></pre>
  
  <p>After I typed <code>rspec spec/models/zombie_spec.rb</code>, it throw <code>uninitialized constant ActiveRecord (NameError)
  </code></p>
  
  <p>I've put this project on <a href="https://github.com/fifiteen82726/Rspec_pra/" rel="nofollow">github</a></p>