@Test
 public void should_return_this() {
   BigDecimalAssert returned = assertions.isZero();
   assertSame(assertions, returned);
 }
 @Test
 public void should_verify_that_actual_is_equal_to_zero() {
   assertions.isZero();
   verify(bigDecimals).assertIsZero(assertions.info, assertions.actual);
 }