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

tests/phpunit.xml

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+<phpunit bootstrap="../autoload.php">
+  <testsuites>
+    <testsuite>
+      <directory>unit/src</directory>
+    </testsuite>
+  </testsuites>
+  <filter>
+    <whitelist processUncoveredFilesFromWhitelist="true">
+      <directory>../src</directory>
+    </whitelist>
+  </filter>
+</phpunit>

tests/unit/src/Example/HelloTest.php

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+<?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);
+		
+	}
+	
+}