This is an example of autoloading classes and including unit tests.

tests/unit/src/Example/HelloTest.php

@@ -0,0 +1,23 @@
+<?php namespace Friendica\Directory\Example;
+
+class HelloTest extends \PHPUnit_Framework_TestCase
+{
+	
+	/**
+	 * Test the sayHello() method.
+	 */
+	public function testSayHello()
+	{
+		
+		//Create a new Hello class instance.
+		$instance = new Hello();
+		
+		//Call the method sayHello() that we want to test.
+		$output = $instance->sayHello();
+		
+		//Check that it returns the message we expect.
+		$this->assertEquals("Hello world!", $output);
+		
+	}
+	
+}