*     zero instead.
   */
  @CanIgnoreReturnValue
  int setCount(@ParametricNullness E element, int count);

  /**
   * Conditionally sets the count of an element to a new value, as described in {@link
   * #setCount(Object, int)}, provided that the element has the expected current count. If the
   * current count is not {@code oldCount}, no change is made.
   *

    // 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;
  }

  static String formatCompact4Digits(double value) {
    return toPrecision(value, 4);
  }

  @JsMethod(name = "Number.prototype.toPrecision.call", namespace = JsPackage.GLOBAL)
  private static native String toPrecision(double value, int precision);

  @JsMethod

  public void testConcat_overflow_negative() {
    int dim1 = 1 << 16;
    int dim2 = 1 << 15;
    assertThat(dim1 * dim2).isLessThan(0);
    testConcatOverflow(dim1, dim2);
  }

  @GwtIncompatible // different overflow behavior; could probably be made to work by using ~~
  public void testConcat_overflow_nonNegative() {
    int dim1 = 1 << 16;
    int dim2 = 1 << 16;
    assertThat(dim1 * dim2).isAtLeast(0);

  public void testConcat_overflow_negative() {
    int dim1 = 1 << 16;
    int dim2 = 1 << 15;
    assertThat(dim1 * dim2).isLessThan(0);
    testConcatOverflow(dim1, dim2);
  }

  @GwtIncompatible // different overflow behavior; could probably be made to work by using ~~
  public void testConcat_overflow_nonNegative() {
    int dim1 = 1 << 16;
    int dim2 = 1 << 16;
    assertThat(dim1 * dim2).isAtLeast(0);

   */
  public static void checkPositionIndexes(int start, int end, int size) {
    // Carefully optimized for execution by hotspot (explanatory comment above)
    if (start < 0 || end < start || end > size) {
      throw new IndexOutOfBoundsException(badPositionIndexes(start, end, size));
    }
  }

  private static String badPositionIndexes(int start, int end, int size) {
    if (start < 0 || start > size) {

      ByteSource
  {

    final byte[] bytes;
    final int offset;
    final int length;

    ByteArrayByteSource(byte[] bytes) {
      this(bytes, 0, bytes.length);
    }

    // NOTE: Preconditions are enforced by slice, the only non-trivial caller.
    ByteArrayByteSource(byte[] bytes, int offset, int length) {
      this.bytes = bytes;
      this.offset = offset;

    SerializableTester.reserializeAndAssert(Equivalence.equals());
    SerializableTester.reserializeAndAssert(Equivalence.identity());
  }

  private static class IntValue {
    private final int value;

    IntValue(int value) {
      this.value = value;
    }

    @Override
    public String toString() {
      return "value = " + value;
    }
  }

  public void testOnResultOf() {

    SerializableTester.reserializeAndAssert(Equivalence.equals());
    SerializableTester.reserializeAndAssert(Equivalence.identity());
  }

  private static class IntValue {
    private final int value;

    IntValue(int value) {
      this.value = value;
    }

    @Override
    public String toString() {
      return "value = " + value;
    }
  }

  public void testOnResultOf() {

  })
  @ParametricNullness
  final V blockingGet(long timeout, TimeUnit unit)
      throws InterruptedException, TimeoutException, ExecutionException {
    // NOTE: if timeout < 0, remainingNanos will be < 0 and we will fall into the while(true) loop
    // at the bottom and throw a timeoutexception.
    long timeoutNanos = unit.toNanos(timeout); // we rely on the implicit null check on unit.
    long remainingNanos = timeoutNanos;

     *
     * @param crudMode the actual CRUD mode provided
     * @param expectedMode the expected CRUD mode
     */
    protected void verifyCrudMode(final int crudMode, final int expectedMode) {
        if (crudMode != expectedMode) {
            throwValidationError(messages -> {
                messages.addErrorsCrudInvalidMode(GLOBAL, String.valueOf(expectedMode), String.valueOf(crudMode));