@Test
public void positives() {

    assertThat(new PageNumbersListAdapter("1").getPageNumbers(), contains(1));
    assertThat(new PageNumbersListAdapter("1,3,6").getPageNumbers(), contains(1, 3, 6));
    assertThat(new PageNumbersListAdapter(" 1, 3, 6 ").getPageNumbers(), contains(1, 3, 6));
}