new RoundToDoubleTester(BigInteger.valueOf((-1L << 53) - 1))
        .setExpectation(-Math.pow(2, 53), DOWN, CEILING, HALF_DOWN, HALF_EVEN)
        .setExpectation(DoubleUtils.nextDown(-Math.pow(2, 53)), FLOOR, UP, HALF_UP)
        .roundUnnecessaryShouldThrow()
        .test();
  }

  @J2ktIncompatible
  @GwtIncompatible
  public void testRoundToDouble_negativeTwoToThe54MinusOne() {

            ? roundArbitrarily
            : DoubleUtils.nextDown(roundArbitrarily);
      case CEILING:
        return (cmpXToRoundArbitrarily <= 0) ? roundArbitrarily : Math.nextUp(roundArbitrarily);
      case DOWN:
        if (x >= 0) {
          return (cmpXToRoundArbitrarily >= 0)
              ? roundArbitrarily
              : DoubleUtils.nextDown(roundArbitrarily);
        } else {

      for (int direction : new int[] {1, -1}) {
        double d = Double.longBitsToDouble(Double.doubleToLongBits(Math.scalb(1.0, i)) + direction);
        // Math.nextUp/nextDown
        if (d != Math.rint(d)) {
          fractionalBuilder.add(d);
        }
      }
    }
    for (double d :
        Doubles.asList(
            0,
            1,
            2,

      } while (approxCmp > 0);
    } else {
      BigInteger nextPow = BigInteger.TEN.multiply(approxPow);
      int nextCmp = nextPow.compareTo(x);
      while (nextCmp <= 0) {
        approxLog10++;
        approxPow = nextPow;
        approxCmp = nextCmp;
        nextPow = BigInteger.TEN.multiply(approxPow);
        nextCmp = nextPow.compareTo(x);
      }
    }

    int floorLog = approxLog10;