Ysul
$ phpcs ERROR: PHP_CodeSniffer requires the tokenizer extension to be enabled. $ psysh Fatal error: Uncaught Error: Call to undefined function PhpParser\token_name() in phar:///opt/psysh/psysh/build-vendor/nikic/php-parser/lib/PhpParser/Lexer.php:359 Stack trace: #0 phar:///opt/psysh/psysh/build-vendor/nikic/php-parser/lib/PhpParser/Lexer.php(32): PhpParser\Lexer->createTokenMap() #1 phar:///opt/psysh/psysh/build-vendor/nikic/php-parser/lib/PhpParser/Lexer/Emulative.php(24): PhpParser\Lexer->__construct(Array) #2 phar:///opt/psysh/psysh/build-vendor/nikic/php-parser/lib/PhpParser/ParserFactory.php(22): PhpParser\Lexer\Emulative->__construct() #3 phar:///opt/psysh/psysh/src/Psy/ParserFactory.php(80): PhpParser\ParserFactory->create(3) #4 phar:///opt/psysh/psysh/src/Psy/CodeCleaner.php(64): Psy\ParserFactory->createParser() #5 phar:///opt/psysh/psysh/src/Psy/Configuration.php(761): Psy\CodeCleaner->__construct() #6 phar:///opt/psysh/psysh/src/Psy/Shell.php(79): Psy\Configuration->getCodeCleaner() #7 phar:///opt/psysh/psysh/src/Psy/functions.php(286): Psy\Shell->__construct(Object(Psy\Configuration)) #8 /opt/p in phar:///opt/psysh/psysh/build-vendor/nikic/php-parser/lib/PhpParser/Lexer.php on line 359
phpcs prints this message if extension_loaded('tokenizer') returns False.