}
  }

  @GwtIncompatible // DoubleMath.roundToLong(double, RoundingMode)
  public void testRoundNaNToLongAlwaysFails() {
    for (RoundingMode mode : ALL_ROUNDING_MODES) {
      assertThrows(ArithmeticException.class, () -> DoubleMath.roundToLong(Double.NaN, mode));
    }
  }

  @GwtIncompatible // DoubleMath.roundToLong(double, RoundingMode)

    }
  }

  @GwtIncompatible // DoubleMath.roundToLong(double, RoundingMode)
  public void testRoundNaNToLongAlwaysFails() {
    for (RoundingMode mode : ALL_ROUNDING_MODES) {
      assertThrows(ArithmeticException.class, () -> DoubleMath.roundToLong(Double.NaN, mode));
    }
  }

  @GwtIncompatible // DoubleMath.roundToLong(double, RoundingMode)

     * is close to 1 (why?), gives the following formula.
     */
    double fractionOfBitsSet = (double) bitCount / bitSize;
    return DoubleMath.roundToLong(
        -Math.log1p(-fractionOfBitsSet) * bitSize / numHashFunctions, RoundingMode.HALF_UP);
  }

  /** Returns the number of bits in the underlying bit array. */
  @VisibleForTesting
  long bitSize() {