public void testEquality() {
    new EqualsTester()
        .addEqualityGroup(idn("google.com"), idn("google.com"), idn("GOOGLE.COM"))
        .addEqualityGroup(idn("www.google.com"))
        .addEqualityGroup(UNICODE_EXAMPLE)
        .addEqualityGroup(PUNYCODE_EXAMPLE)
        .testEquals();
  }

  private static InternetDomainName idn(String domain) {
    return InternetDomainName.from(domain);
  }