That is not a "testcase". A "testcase" is something that, when run, returns SUCCESS, FAILURE or ERROR dependent on how it performs and how it is coded based on expectations.

That aside, you decide to run non-transactional and then use an extension based on being transactional (loadResultsAtCommit), which makes no sense.

You also run non-transactional and expect any connection to be held open until the end of PM, without specifying datanucleus.connection.nontx.releaseAfterUse.
https://www.datanucleus.org/products/accessplatform_5_2/jdo/persistence.html#_nontransactional_context



Clearly better error messages could be provided, but then people could contribute such handling.