I've briefly looked through the documentation I could find based on some relevant searches, but I'm not 100% on what is actually handling the regex matching when using validation in my questions. Is it PHP-based or JavaScript-based?

Thank you!

PHP and JS

github.com/LimeSurvey/LimeSurvey/blob/ma...ore_helper.php#L2979

and

github.com/LimeSurvey/LimeSurvey/blob/ma...m_javascript.js#L388

Super helpful. Thank you for the links!

So, with that being said - how do I adequately test my regex patterns before making a survey live?

Hi, see for example: regex101.com/ . There are many more...

Thank you for the reply. To be direct - I'm aware of online tools such as www.regex101.com (my personal favorite) that can help me test my patterns. So, I apologize if I wasn't being clear enough with my previous question.

I was trying to ascertain when/if my patterns were being evaluated on the PHP side (using the PCRE engine) or on the front-end side (JavaScript). Which, would affect the patterns being valid when being executed, respectively.

I was having issues with some of in my inputs where I attached the aforementioned regex patterns and the error/notification messages weren't referring to any specific question that wasn't passing its validation. Hence, where my question was coming from.