public DefaultIssue setStatus(String s) {
    Preconditions.checkArgument(!Strings.isNullOrEmpty(s), "Status must be set");
    this.status = s;
    return this;
  }
@Test
  void fail_on_empty_status() {
    try {
      issue.setStatus("");
      fail();
    } catch (IllegalArgumentException e) {
      assertThat(e).hasMessage("Status must be set");
    }
  }