PhpCsFixer\Fixer\ControlStructure\ElseifFixer::fix PHP Метод

    public function fix(\SplFileInfo $file, Tokens $tokens)
    {
        foreach ($tokens as $index => $token) {
            if (!$token->isGivenKind(T_ELSE)) {
                continue;
            }
            $ifTokenIndex = $tokens->getNextMeaningfulToken($index);
            $beforeIfTokenIndex = $tokens->getPrevNonWhitespace($ifTokenIndex);
            // if next meaning token is not T_IF - continue searching, this is not the case for fixing
            if (!$tokens[$ifTokenIndex]->isGivenKind(T_IF)) {
                continue;
            }
            // now we have T_ELSE following by T_IF so we could fix this
            // 1. clear whitespaces between T_ELSE and T_IF
            $tokens[$index + 1]->clear();
            // 2. change token from T_ELSE into T_ELSEIF
            $tokens->overrideAt($index, array(T_ELSEIF, 'elseif'));
            // 3. clear succeeding T_IF
            $tokens[$ifTokenIndex]->clear();
            // 4. clear extra whitespace after T_IF in T_COMMENT,T_WHITESPACE?,T_IF,T_WHITESPACE sequence
            if ($tokens[$beforeIfTokenIndex]->isComment() && $tokens[$ifTokenIndex + 1]->isWhitespace()) {
                $tokens[$ifTokenIndex + 1]->clear();
            }
        }
    }