Fatal error: Uncaught Error: Class "PHPUnit_Framework_TestCase" not found in C:\xampp8\htdocs\Gsheet\vendor\paragonie\constant_time_encoding\tests\Base64DotSlashOrderedTest.php:4 Stack trace: #0 {main} thrown in C:\xampp8\htdocs\Gsheet\vendor\paragonie\constant_time_encoding\tests\Base64DotSlashOrderedTest.php on line 4