Yii 1.1.x is not perfectly compatible with Phpunit 4.x
While waiting for a clean and definitive solution provided by Yii development team, I commented these lines in my CTestCase.php:
//require_once('PHPUnit/Runner/Version.php');
//require_once('PHPUnit/Util/Filesystem.php'); // workaround for PHPUnit <= 3.6.11
spl_autoload_unregister(array('YiiBase','autoload'));
//require_once('PHPUnit/Autoload.php');
spl_autoload_register(array('YiiBase','autoload')); // put yii's autoloader at the end
I found that this issue was already reported on Yii Issue tracker (I can’t post here the link, because the forum security policy doesn’t allow me to write a link…)
The current version of CTestCase.php on GitHub Yii repository has been modified to solve problems with Phpunit 3.8+