def test_update_instance_err(self, mockInst):
testWork = Work()
testWork.session = 'session'
mockInst.update.side_effect = DataError('test err')
testWork.updateInstance(mockInst, 'inst1')
self.assertEqual(testWork.instances, set())
def test_update_instance(self, mockInst):
testWork = Work()
testWork.epubsToLoad = []
testWork.session = 'session'
testWork.updateInstance(mockInst, 'newInst')
mockInst.update.assert_called_once_with('session', 'newInst')