@Test
public void testToString() {

  BigIntegerFieldDefinition fd500 = new BigIntegerFieldDefinition(
      ModulusFinder.findSuitableModulus(8));
  DummyArithmeticSInt value = new DummyArithmeticSInt(fd500.createElement(42));
  String toString = value.toString();
  Assert.assertThat(toString, StringContains.containsString("42"));
  Assert.assertThat(value.toString(), Is.is(toString));
}