def METHOD_NAME(self):
    with set_refprune_flags('abc,per_bb,cde'):
        with self.assertWarns(NumbaInvalidConfigWarning) as cm:
            optval = _parse_refprune_flags()
        self.assertEqual(len(cm.warnings), 2)
        self.assertIn('abc', str(cm.warnings[0].message))
        self.assertIn('cde', str(cm.warnings[1].message))
        self.assertEqual(optval, llvm.RefPruneSubpasses.PER_BB)