@Test
public void invokeNull3ParamsMethod() {

    FunctionTestUtil.assertResultError(substringFunction.invoke(null, null, null), InvalidParametersEvent.class);
    FunctionTestUtil.assertResultError(substringFunction.invoke("test", null, null), InvalidParametersEvent.class);
    FunctionTestUtil.assertResultError(substringFunction.invoke("test", null, 2), InvalidParametersEvent.class);
    FunctionTestUtil.assertResultError(substringFunction.invoke(null, 0, null), InvalidParametersEvent.class);
    FunctionTestUtil.assertResultError(substringFunction.invoke(null, null, 2), InvalidParametersEvent.class);
    FunctionTestUtil.assertResultError(substringFunction.invoke(null, 0, 2), InvalidParametersEvent.class);
}