@Override
    public void setParameters(Collection<CompoundVariable> parameters)
            throws InvalidVariableException {
        checkParameterCount(parameters, MIN_PARAMETER_COUNT,
                MAX_PARAMETER_COUNT);
        values = parameters.toArray(new CompoundVariable[parameters.size()]);
    }
@Test
    public void testIsPropDefinedError() {
        Assertions.assertThrows(
                InvalidVariableException.class,
                () -> isPropDefined.setParameters(params));
    }