assertTrue(TEN.pow(result).compareTo(x) <= 0);
        assertTrue(TEN.pow(result + 1).compareTo(x) > 0);
      }
    }
  }

  @GwtIncompatible // TODO
  public void testLog10Ceiling() {
    for (BigInteger x : POSITIVE_BIGINTEGER_CANDIDATES) {
      for (RoundingMode mode : asList(CEILING, UP)) {
        int result = BigIntegerMath.log10(x, mode);