reallyTestNoMatchThenMatch(matcher.precomputed().negate(), s);
  }

  private void doTestNoMatchThenMatch(CharMatcher matcher, String s) {
    reallyTestNoMatchThenMatch(matcher, s);
    reallyTestMatchThenNoMatch(matcher.negate(), s);
    reallyTestNoMatchThenMatch(matcher.precomputed(), s);
    reallyTestMatchThenNoMatch(matcher.negate().precomputed(), s);

    reallyTestNoMatchThenMatch(matcher.precomputed().negate(), s);
  }

  private void doTestNoMatchThenMatch(CharMatcher matcher, String s) {
    reallyTestNoMatchThenMatch(matcher, s);
    reallyTestMatchThenNoMatch(matcher.negate(), s);
    reallyTestNoMatchThenMatch(matcher.precomputed(), s);
    reallyTestMatchThenNoMatch(matcher.negate().precomputed(), s);

/** @author Jesse Wilson */
final class Platform {
  static CharMatcher precomputeCharMatcher(CharMatcher matcher) {
    // CharMatcher.precomputed() produces CharMatchers that are maybe a little
    // faster (and that's debatable), but definitely more memory-hungry. We're
    // choosing to turn .precomputed() into a no-op in GWT, because it doesn't
    // seem to be a worthwhile tradeoff in a browser.
    return matcher;
  }

   * worthwhile only if the precomputed matcher is queried many thousands of times.
   *
   * <p>This method has no effect (returns {@code this}) when called in GWT: it's unclear whether a
   * precomputed matcher is faster, but it certainly consumes more memory, which doesn't seem like a
   * worthwhile tradeoff in a browser.
   */
  public CharMatcher precomputed() {
    return Platform.precomputeCharMatcher(this);

   * worthwhile only if the precomputed matcher is queried many thousands of times.
   *
   * <p>This method has no effect (returns {@code this}) when called in GWT: it's unclear whether a
   * precomputed matcher is faster, but it certainly consumes more memory, which doesn't seem like a
   * worthwhile tradeoff in a browser.
   */
  public CharMatcher precomputed() {
    return Platform.precomputeCharMatcher(this);

        return isPowerOfTwo(x) ? logFloor : logFloor + 1;

      case HALF_DOWN:
      case HALF_UP:
      case HALF_EVEN:
        if (logFloor < SQRT2_PRECOMPUTE_THRESHOLD) {
          BigInteger halfPower =
              SQRT2_PRECOMPUTED_BITS.shiftRight(SQRT2_PRECOMPUTE_THRESHOLD - logFloor);
          if (x.compareTo(halfPower) <= 0) {
            return logFloor;
          } else {
            return logFloor + 1;

  @GwtIncompatible // TODO
  public void testConstantSqrt2PrecomputedBits() {
    assertEquals(
        BigIntegerMath.sqrt(
            BigInteger.ZERO.setBit(2 * BigIntegerMath.SQRT2_PRECOMPUTE_THRESHOLD + 1), FLOOR),
        BigIntegerMath.SQRT2_PRECOMPUTED_BITS);
  }

  public void testIsPowerOfTwo() {
    for (BigInteger x : ALL_BIGINTEGER_CANDIDATES) {
      // Checks for a single bit set.

  @GwtIncompatible // TODO
  public void testConstantSqrt2PrecomputedBits() {
    assertEquals(
        BigIntegerMath.sqrt(
            BigInteger.ZERO.setBit(2 * BigIntegerMath.SQRT2_PRECOMPUTE_THRESHOLD + 1), FLOOR),
        BigIntegerMath.SQRT2_PRECOMPUTED_BITS);
  }

  public void testIsPowerOfTwo() {
    for (BigInteger x : ALL_BIGINTEGER_CANDIDATES) {
      // Checks for a single bit set.

  @Param({"64", "1024"})
  int length;

  // Percent of string that the CharMatcher matches
  @Param({"0", "10", "50", "100"})
  int percent;

  // Whether to use a precomputed CharMatcher
  @Param("true")
  boolean precomputed;

  enum Size {
    DEFAULT,
    SMALL;
  }

  @Param Size size;

  // Whether to ensure there is a matching character in the first position

  @Param({"64", "1024"})
  int length;

  // Percent of string that the CharMatcher matches
  @Param({"0", "10", "50", "100"})
  int percent;

  // Whether to use a precomputed CharMatcher
  @Param("true")
  boolean precomputed;

  enum Size {
    DEFAULT,
    SMALL;
  }

  @Param Size size;

  // Whether to ensure there is a matching character in the first position