};
    int[] bases = {2, 5, 7, 8, 10, 16};
    for (int base : bases) {
      for (String x : tests) {
        BigInteger xValue = new BigInteger(x, 16);
        long xLong = xValue.longValue(); // signed
        assertThat(UnsignedLongs.toString(xLong, base)).isEqualTo(xValue.toString(base));
      }
    }
  }

  public void testJoin() {
    assertThat(UnsignedLongs.join(",")).isEmpty();

    };
    int[] bases = {2, 5, 7, 8, 10, 16};
    for (int base : bases) {
      for (String x : tests) {
        BigInteger xValue = new BigInteger(x, 16);
        long xLong = xValue.longValue(); // signed
        assertThat(UnsignedLongs.toString(xLong, base)).isEqualTo(xValue.toString(base));
      }
    }
  }

  public void testJoin() {
    assertThat(UnsignedLongs.join(",")).isEmpty();