@Test
public void invokeInvalidParams() {

    FunctionTestUtil.assertResultError(appendFunction.invoke((List) null, null), InvalidParametersEvent.class);
    FunctionTestUtil.assertResultError(appendFunction.invoke((List) null, new Object[]{}), InvalidParametersEvent.class);
    FunctionTestUtil.assertResultError(appendFunction.invoke(Collections.emptyList(), null), InvalidParametersEvent.class);
}