Fatal error: Uncaught Error: Class 'Doctrine\Common\Lexer\AbstractLexer' not found in E:\xampp\htdocs\key1\vendor\doctrine\lexer\tests\Doctrine\Common\Lexer\ConcreteLexer.php:7 Stack trace: #0 {main} thrown in E:\xampp\htdocs\key1\vendor\doctrine\lexer\tests\Doctrine\Common\Lexer\ConcreteLexer.php on line 7