class LowerCaseKeywordSniff

class LowerCaseKeywordSniff implements Sniff {
    
    /**
     * Returns an array of tokens this test wants to listen for.
     *
     * @return array<int|string>
     */
    public function register() {
        $targets = Tokens::$contextSensitiveKeywords;
        $targets += [
            T_ANON_CLASS => T_ANON_CLASS,
            T_CLOSURE => T_CLOSURE,
            T_ENUM_CASE => T_ENUM_CASE,
            T_MATCH_DEFAULT => T_MATCH_DEFAULT,
            T_PARENT => T_PARENT,
            T_SELF => T_SELF,
        ];
        return $targets;
    }
    
    //end register()
    
    /**
     * Processes this sniff, when one of its tokens is encountered.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
     * @param int                         $stackPtr  The position of the current token in the
     *                                               stack passed in $tokens.
     *
     * @return void
     */
    public function process(File $phpcsFile, $stackPtr) {
        $tokens = $phpcsFile->getTokens();
        $keyword = $tokens[$stackPtr]['content'];
        if (strtolower($keyword) !== $keyword) {
            if ($keyword === strtoupper($keyword)) {
                $phpcsFile->recordMetric($stackPtr, 'PHP keyword case', 'upper');
            }
            else {
                $phpcsFile->recordMetric($stackPtr, 'PHP keyword case', 'mixed');
            }
            $messageKeyword = Common::prepareForOutput($keyword);
            $error = 'PHP keywords must be lowercase; expected "%s" but found "%s"';
            $data = [
                strtolower($messageKeyword),
                $messageKeyword,
            ];
            $fix = $phpcsFile->addFixableError($error, $stackPtr, 'Found', $data);
            if ($fix === true) {
                $phpcsFile->fixer
                    ->replaceToken($stackPtr, strtolower($keyword));
            }
        }
        else {
            $phpcsFile->recordMetric($stackPtr, 'PHP keyword case', 'lower');
        }
        
        //end if
    }
    
    //end process()

}