Do you need to use the TestFilter? If it's as simple as testing an attribute for a code, you could use the AttributeFilter, this will allow you to import the codes from the csv

Thanks but some of the codes are not an exact match so i need to also use operators like "Begins with" or "Contains regex". I've just had a quick look and I don't see any option to do that with the AttributeFilter

I'd probably still try and use the attribute filter, anything to avoid having to write 100 test statements! So find some method of adding the code as it's own attribute to the data, and then use the attributefilter on that. e.g. you could use an inlinequerier to join the code to the attribute that contains the code, then use the code for your filter.