Long address texts are overlapped on invoice/creditmemo pdf

[HirokazuNishi]

Preconditions

1. Install Magento2.3.4 with sample data.
2. Install CommunityEngineering_ConfigurablePdfFont.
3. Create customer account with long address text data.
4. Create order.
5. Create invoice.

Expected result

• Invoice pdf generated without any broken layout.

Actual result

• Invoice pdf generated with broken layout. Cannot read customer address.

Issue reason

Magento\Framework\Stdlib\StringUtils has 2 methods strlen and split. These are useful for single byte characters for PDF generation. For pdf generation, we have to check the text contains double byte characters or not.

[lenaorobei]

@HirokazuNishi looks like strlen uses mb_strlen and split uses binary safe split so this might be not the reason of the issue.

[HirokazuNishi]

@lenaorobei for PDF generation, we have to mind character width , too. mb_strwidth can detect the given string contain only single bytes or not. The issue reason is, strlen and split functions in StringUtils doesn't check string width against double byte characters.

[sukeshini-kot]

Same issue occurs when there are long product names in the invoice or in other PDFs. Is there any workaround for this?

[HirokazuNishi]

@sukeshini-kot You need to define plugin against StringUtils.

[sukeshini-kot]

@HirokazuNishi Thank you very much. Adding an around plugin to strlen() solved the issue.

public function aroundStrlen(
        \Magento\Framework\Stdlib\StringUtils $subject,
        \Closure $proceed,
        $string
    ) {
        if ($string !== null) {
            if (mb_strlen($string, 'UTF-8') !== strlen($string)) {
                // String contains multibyte characters
                return strlen($string);
            }
            return $proceed($string);
        }
        return 0;
    }