PhpCsFixer\Fixer\PhpTag\BlankLineAfterOpeningTagFixer::fix PHP Method

    public function fix(\SplFileInfo $file, Tokens $tokens)
    {
        $lineEnding = $this->whitespacesConfig->getLineEnding();
        // ignore files with short open tag and ignore non-monolithic files
        if (!$tokens[0]->isGivenKind(T_OPEN_TAG) || !$tokens->isMonolithicPhp()) {
            return;
        }
        $newlineFound = false;
        /** @var Token $token */
        foreach ($tokens as $token) {
            if ($token->isWhitespace() && false !== strpos($token->getContent(), "\n")) {
                $newlineFound = true;
                break;
            }
        }
        // ignore one-line files
        if (!$newlineFound) {
            return;
        }
        $token = $tokens[0];
        if (false === strpos($token->getContent(), "\n")) {
            $token->setContent(rtrim($token->getContent()) . $lineEnding);
        }
        if (!$tokens[1]->isWhitespace() && false === strpos($tokens[1]->getContent(), "\n")) {
            $tokens->insertAt(1, new Token(array(T_WHITESPACE, $lineEnding)));
        }
    }