Testing PHPUnit

I'm running the unit tests included in PHPUnit to verify my installation.

I get the same results running from the IDE and from the command line.

Says it can't find the Success class. But the IDE finds it with no problem in C:\Users\user\Documents\Projects\PHP\vendor\phpunit\phpunit\tests\_files with all the rest of the support files.

I can't see any reason for it not to be found.

"C:\Program Files\PHP\5.6\php.exe" C:/Users/user/AppData/Local/Temp/ide-phpunit.php --configuration C:\Users\user\Documents\Projects\PHP\vendor\phpunit\phpunit.xml

Testing started at 4:26 AM ...

PHP Fatal error: Class 'Success' not found in C:\Users\user\Documents\Projects\PHP\vendor\phpunit\phpunit\tests\Extensions\RepeatedTestTest.php on line 23

PHP v 5.6

PHPUnit v 5.0.3