Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in /home/www/drupal8/test/core/tests/Drupal/Tests/Component/Datetime/TimeTest.php:18
Stack trace:
#0 {main}
thrown in /home/www/drupal8/test/core/tests/Drupal/Tests/Component/Datetime/TimeTest.php on line 18