    @Test
    void shouldFailOnStartDateOnlySpecified() {

        // given
        Rule rule = new Rule(new LinkedHashSet<>(Arrays.asList(
                new Attribute("ruleName", String.class, "ruleName"),
                new Attribute("startDate", ZonedDateTime.class, ZonedDateTime.parse("2012-01-05T00:00:00+12:34"))
        )), Collections.emptyList(), null, Collections.emptyList());

        // when
        ValidationResults results = validator.validate(rule);

        // then
        assertThat(results.getResults()).containsExactly(
                ValidationResult.error("rule.attribute.expire-date-attribute-not-defined", "Attribute Error: \"expireDate\" was not specified while \"startDate\" was")
        );
    }