<!-- TODO(cpovirk): Enable NullArgumentForNonNullParameter for
                   prod code. It's disabled automatically for "test code"
                   (which is good: our tests have intentional violations), but
                   Error Prone doesn't know it's building test code unless we
                   pass -XepCompilingTestOnlyCode, and that argument needs to

   */
  @Override
  public ImmutableSet<K> keySet() {
    ImmutableSet<K> result = keySet;
    return (result == null) ? keySet = createKeySet() : result;
  }

  /*
   * This could have a good default implementation of return new ImmutableKeySet<K, V>(this),
   * but ProGuard can't figure out how to eliminate that default when RegularImmutableMap
   * overrides it.
   */
  abstract ImmutableSet<K> createKeySet();

    // do n swaps, minus a delta (0 or 2 for Reversal, gcd(d, n) for Successive), so that's about
    // twice as many reads and writes. But benchmarking shows that they usually perform better than
    // Dolphin. Reversal is about as good as Successive on average, and it is much simpler,
    // especially since we already have a `reverse` method.
    checkNotNull(array);
    checkPositionIndexes(fromIndex, toIndex, array.length);
    if (array.length <= 1) {

 *
 * <p>{@code containsKey(k)}, {@code put(k, v)} and {@code remove(k)} are all (expected and
 * amortized) constant time operations. Expected in the hashtable sense (depends on the hash
 * function doing a good job of distributing the elements to the buckets to a distribution not far
 * from uniform), and amortized since some operations can trigger a hash table resize.
 *

   */
  @Override
  public ImmutableSet<K> keySet() {
    ImmutableSet<K> result = keySet;
    return (result == null) ? keySet = createKeySet() : result;
  }

  /*
   * This could have a good default implementation of return new ImmutableKeySet<K, V>(this),
   * but ProGuard can't figure out how to eliminate that default when RegularImmutableMap
   * overrides it.
   */

    frame.writeByte(TYPE_GOAWAY)
    frame.writeByte(FLAG_NONE)
    frame.writeInt(0) // connection-scope
    frame.writeInt(expectedStreamId) // last good stream.
    frame.writeInt(expectedError.httpCode)

    // Check writer sends the same bytes.
    assertThat(sendGoAway(expectedStreamId, expectedError, EMPTY_BYTE_ARRAY))
      .isEqualTo(frame)

  }

  /**
   * All of the infrastructure of split and splitToString is identical, so we do one test of
   * splitToString. All other cases should be covered by testing of split.
   *
   * <p>TODO(user): It would be good to make all the relevant tests run on both split and
   * splitToString automatically.
   */
  public void testCharacterSimpleSplitToList() {
    String simple = "a,b,c";

   * Returns a new builder with a hint for how many distinct keys are expected to be added. The
   * generated builder is equivalent to that returned by {@link #builder}, but may perform better if
   * {@code expectedKeys} is a good estimate.
   *
   * @throws IllegalArgumentException if {@code expectedKeys} is negative
   * @since 33.3.0
   */
  public static <K, V> Builder<K, V> builderWithExpectedKeys(int expectedKeys) {

   * Returns a new builder with a hint for how many distinct keys are expected to be added. The
   * generated builder is equivalent to that returned by {@link #builder}, but may perform better if
   * {@code expectedKeys} is a good estimate.
   *
   * @throws IllegalArgumentException if {@code expectedKeys} is negative
   * @since 33.3.0
   */
  public static <K, V> Builder<K, V> builderWithExpectedKeys(int expectedKeys) {

		for _, startLen := range []int{0, 100, 1000, 10000, 100000} {
			xBytes := Repeat(x, startLen)

			buf := NewBuffer(xBytes)
			// If we read, this affects buf.off, which is good to test.
			readBytes, _ := buf.Read(tmp)
			yBytes := Repeat(y, growLen)
			allocs := testing.AllocsPerRun(100, func() {
				buf.Grow(growLen)
				buf.Write(yBytes)
			})