Got/Sniffs/Strings/ConcatenationSpacingSniff.php
public function process(PHP_CodeSniffer_File $phpCsFile, $stackPtr)
    {
        $tokens = $phpCsFile->getTokens();
        if ($tokens[($stackPtr - 1)]['code'] !== T_WHITESPACE or $tokens[($stackPtr + 1)]['code'] !== T_WHITESPACE) {
            $phpCsFile->addError('Concat operator must be surrounded by spaces', $stackPtr, 'Missing');
        }
    }
public function process(PHP_CodeSniffer_File $phpCsFile, $stackPtr)
    {
        $tokens = $phpCsFile->getTokens();
        if ($tokens[($stackPtr - 1)]['code'] !== T_WHITESPACE or $tokens[($stackPtr + 1)]['code'] !== T_WHITESPACE) {
            $phpCsFile->addError('Concat operator must be surrounded by spaces', $stackPtr, 'Missing');
        }
    }
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