I would appreciate a lot anyone who
would declare what I should test and why. eg. Xpath
expressions, functions etc.
That rather depends on what you want to find out.
If you are interested in performance when handling large source
documents, then test the performance when handling large source
If you are interested in the quality of the error messages, then test
how the processors react to errors.
Only you can know why you are embarking on this exercise.
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