@Test(expected = IllegalArgumentException.class)
public void should_throw_illegal_argument_exception_when_second_separator_is_null() {

    // given
    final Separator semiColonSeparator = new Separator(';');
    // when
    SeparatorAnalyzer separatorAnalyzer = new SeparatorAnalyzer(1, Collections.emptyList());
    // then
    separatorAnalyzer.compare(semiColonSeparator, null);
}