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<?php
/**
 * Squiz_Sniffs_Functions_FunctionDuplicateArgumentSpacingSniff.
 *
 * PHP version 5
 *
 * @category  PHP
 * @package   PHP_CodeSniffer
 * @author    Greg Sherwood <gsherwood@squiz.net>
 * @author    Marc McIntyre <mmcintyre@squiz.net>
 * @copyright 2006-2014 Squiz Pty Ltd (ABN 77 084 670 600)
 * @license   https://github.com/squizlabs/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
 * @link      http://pear.php.net/package/PHP_CodeSniffer
 */

/**
 * Squiz_Sniffs_Functions_FunctionDuplicateArgumentSpacingSniff.
 *
 * Checks that duplicate arguments are not used in function declarations.
 *
 * @category  PHP
 * @package   PHP_CodeSniffer
 * @author    Greg Sherwood <gsherwood@squiz.net>
 * @author    Marc McIntyre <mmcintyre@squiz.net>
 * @copyright 2006-2014 Squiz Pty Ltd (ABN 77 084 670 600)
 * @license   https://github.com/squizlabs/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
 * @version   Release: 1.5.5
 * @link      http://pear.php.net/package/PHP_CodeSniffer
 */
class Squiz_Sniffs_Functions_FunctionDuplicateArgumentSniff implements PHP_CodeSniffer_Sniff
{


    /**
     * Returns an array of tokens this test wants to listen for.
     *
     * @return array
     */
    public function register()
    {
        return array(T_FUNCTION);

    }//end register()


    /**
     * Processes this test, when one of its tokens is encountered.
     *
     * @param PHP_CodeSniffer_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(PHP_CodeSniffer_File $phpcsFile, $stackPtr)
    {
        $tokens = $phpcsFile->getTokens();

        $openBracket  = $tokens[$stackPtr]['parenthesis_opener'];
        $closeBracket = $tokens[$stackPtr]['parenthesis_closer'];

        $foundVariables = array();
        for ($i = ($openBracket + 1); $i < $closeBracket; $i++) {
            if ($tokens[$i]['code'] === T_VARIABLE) {
                $variable = $tokens[$i]['content'];
                if (in_array($variable, $foundVariables) === true) {
                    $error = 'Variable "%s" appears more than once in function declaration';
                    $data  = array($variable);
                    $phpcsFile->addError($error, $i, 'Found', $data);
                } else {
                    $foundVariables[] = $variable;
                }
            }
        }

    }//end process()


}//end class

?>