Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /data/htmlwww/workspace/web-tubanzhang/vendor/guzzlehttp/promises/tests/TaskQueueTest.php:7 Stack trace: #0 {main} thrown in /data/htmlwww/workspace/web-tubanzhang/vendor/guzzlehttp/promises/tests/TaskQueueTest.php on line 7