title: Testing models using Simpletest and CodeIgniter
body: <p>I am new to the PHP world and I am trying to setup some tests for my models. I am using CodeIgniter and Simpletest. I keep getting this error:</p>
  
  <pre><code>Fatal error: Class 'CI_Model' not found...
  </code></pre>
  
  <p>I assume that this happens because my model extends from <code>CI_Model</code>. <code>CI_Model</code> class has the following code:</p>
  
  <pre><code>if ( ! defined('BASEPATH')) exit('No direct script access allowed');
  </code></pre>
  
  <p>So my question is: how can I test my models using Simpletest?</p>