return s.equals("x") || s.equals("y") || s.equals("z");
              }
            }));
    assertEquals(newArrayList("a", "c", "e"), list);
  }

  public void testRemoveIf_randomAccess_notPermittingDuplicates() {
    // https://github.com/google/guava/issues/1596
    List<String> uniqueList = newArrayList("a", "b", "c", "d", "e");
    assertThat(uniqueList).containsNoDuplicates();