@Test
void should_return_negative_number_when_distance_not_found() {

    when(crudRepository.findById(any(DistanceKey.class))).thenReturn(Optional.empty());
    assertThat(repository.getDistance(from, to))
            .isNegative()
            // Shouldn't be necessary but improves mutation coverage report because Pitest does -(x + 1) mutation,
            // which turns -1 into -0, so this test wouldn't kill that mutation without the following:
            .isNotZero();
}