return null;
    }
    long accum = -digit;

    long cap = Long.MIN_VALUE / radix;

    while (index < string.length()) {
      digit = AsciiDigits.digit(string.charAt(index++));
      if (digit < 0 || digit >= radix || accum < cap) {
        return null;
      }
      accum *= radix;
      if (accum < Long.MIN_VALUE + digit) {
        return null;
      }
      accum -= digit;
    }

    frame.writeByte(Http2.TYPE_SETTINGS)
    frame.writeByte(FLAG_NONE)
    frame.writeInt(0) // Settings are always on the connection stream 0.
    frame.writeShort(4) // SETTINGS_INITIAL_WINDOW_SIZE
    frame.writeInt(Int.MIN_VALUE)
    assertFailsWith<IOException> {
      reader.nextFrame(requireSettings = false, BaseTestHandler())
    }.also { expected ->
      assertThat(expected.message).isEqualTo(

            Lists.newArrayList(),
            null)
        .inOrder();
  }

  public void testNatural() {
    Ordering<Integer> comparator = Ordering.natural();
    Helpers.testComparator(comparator, Integer.MIN_VALUE, -1, 0, 1, Integer.MAX_VALUE);
    try {
      comparator.compare(1, null);
      fail();
    } catch (NullPointerException expected) {
    }
    try {
      comparator.compare(null, 2);
      fail();

   * worthwhile tradeoff in a browser.
   */
  public CharMatcher precomputed() {
    return Platform.precomputeCharMatcher(this);
  }

  private static final int DISTINCT_CHARS = Character.MAX_VALUE - Character.MIN_VALUE + 1;

  /**
   * This is the actual implementation of {@link #precomputed}, but we bounce calls through a method
   * on {@link Platform} so that we can have different behavior in GWT.
   *

   * worthwhile tradeoff in a browser.
   */
  public CharMatcher precomputed() {
    return Platform.precomputeCharMatcher(this);
  }

  private static final int DISTINCT_CHARS = Character.MAX_VALUE - Character.MIN_VALUE + 1;

  /**
   * This is the actual implementation of {@link #precomputed}, but we bounce calls through a method
   * on {@link Platform} so that we can have different behavior in GWT.
   *

@GwtCompatible
@ElementTypesAreNonnullByDefault
public final class UnsignedInts {
  static final long INT_MASK = 0xffffffffL;

  private UnsignedInts() {}

  static int flip(int value) {
    return value ^ Integer.MIN_VALUE;
  }

  /**
   * Compares the two specified {@code int} values, treating them as unsigned values between {@code
   * 0} and {@code 2^32 - 1} inclusive.
   *

@GwtCompatible
@ElementTypesAreNonnullByDefault
public final class UnsignedInts {
  static final long INT_MASK = 0xffffffffL;

  private UnsignedInts() {}

  static int flip(int value) {
    return value ^ Integer.MIN_VALUE;
  }

  /**
   * Compares the two specified {@code int} values, treating them as unsigned values between {@code
   * 0} and {@code 2^32 - 1} inclusive.
   *

  private static final byte[] EMPTY = {};
  private static final byte[] ARRAY1 = {(byte) 1};
  private static final byte[] ARRAY234 = {(byte) 2, (byte) 3, (byte) 4};

  private static final byte[] VALUES = {Byte.MIN_VALUE, -1, 0, 1, Byte.MAX_VALUE};

  public void testHashCode() {
    for (byte value : VALUES) {
      assertThat(Bytes.hashCode(value)).isEqualTo(((Byte) value).hashCode());
    }
  }

  public void testContains() {

   * longs, that is, {@code a <= b} as unsigned longs if and only if {@code flip(a) <= flip(b)} as
   * signed longs.
   */
  private static long flip(long a) {
    return a ^ Long.MIN_VALUE;
  }

  /**
   * Compares the two specified {@code long} values, treating them as unsigned values between {@code
   * 0} and {@code 2^64 - 1} inclusive.
   *

   * longs, that is, {@code a <= b} as unsigned longs if and only if {@code flip(a) <= flip(b)} as
   * signed longs.
   */
  private static long flip(long a) {
    return a ^ Long.MIN_VALUE;
  }

  /**
   * Compares the two specified {@code long} values, treating them as unsigned values between {@code
   * 0} and {@code 2^64 - 1} inclusive.
   *