def wasSuccessful(self):
        """Overrides to check that there are no errors in errorClasses
        lists that are marked as errors and should cause a run to
        fail.
        """
        if self.errors or self.failures:
            return False
        for cls in self.errorClasses.keys():
            storage, label, isfail = self.errorClasses[cls]
            if not isfail:
                continue
            if storage:
                return False
        return True