Fatal error: Uncaught Error: Class "Tests\TestCase" not found in C:\AppServ\Apache\2.4.69\htdocs\isha_security\tests\Feature\ClassTests\RectangleCollectionTest.php:13 Stack trace: #0 {main} thrown in C:\AppServ\Apache\2.4.69\htdocs\isha_security\tests\Feature\ClassTests\RectangleCollectionTest.php on line 13