Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in E:\www\doctor\v1.0\mvc\lib\aliyun-dysms-php-sdk\api_sdk\vendor\sebastian\diff\tests\ChunkTest.php:18 Stack trace: #0 {main} thrown in E:\www\doctor\v1.0\mvc\lib\aliyun-dysms-php-sdk\api_sdk\vendor\sebastian\diff\tests\ChunkTest.php on line 18