public void testAddAllAtIndex_nullSupported() {
    List<E> containsNull = singletonList(null);
    assertTrue("addAll(n, containsNull) should return true", getList().addAll(0, containsNull));
    /*
     * We need (E) to force interpretation of null as the single element of a
     * varargs array, not the array itself
     */
    expectAdded(0, (E) null);
  }

  @ListFeature.Require(SUPPORTS_ADD_WITH_INDEX)

    // may change and break assumptions in this test [*]. This is not a bug in the implementation of
    // Ascii.equalsIgnoreCase(), but it is a signal that its documentation may need updating as
    // regards edge cases.

    // The Unicode point {@code 00df} is the lowercase form of sharp-S (ß), whose uppercase is "SS".
    assertEquals("PASSWORD", "pa\u00dfword".toUpperCase()); // [*]

  @VisibleForTesting
  static class MemoizingSupplier<T extends @Nullable Object> implements Supplier<T>, Serializable {
    final Supplier<T> delegate;
    transient volatile boolean initialized;
    // "value" does not need to be volatile; visibility piggy-backs
    // on volatile read of "initialized".
    @CheckForNull transient T value;

    MemoizingSupplier(Supplier<T> delegate) {
      this.delegate = checkNotNull(delegate);
    }

  public void testAddAll_nullSupported() {
    List<E> containsNull = singletonList(null);
    assertTrue("addAll(containsNull) should return true", collection.addAll(containsNull));
    /*
     * We need (E) to force interpretation of null as the single element of a
     * varargs array, not the array itself
     */
    expectAdded((E) null);
  }

/**
 * A rate limiter. Conceptually, a rate limiter distributes permits at a configurable rate. Each
 * {@link #acquire()} blocks if necessary until a permit is available, and then takes it. Once
 * acquired, permits need not be released.
 *
 * <p>{@code RateLimiter} is safe for concurrent use: It will restrict the total rate of calls from
 * all threads. Note, however, that it does not guarantee fairness.
 *

 * CompletableFuture}. {@code FluentFuture} is targeted at people who use {@code ListenableFuture},
 * who can't use Java 8, or who want an API more focused than {@code CompletableFuture}. (If you
 * need to adapt between {@code CompletableFuture} and {@code ListenableFuture}, consider <a
 * href="https://github.com/lukas-krecan/future-converter">Future Converter</a>.)
 *
 * <h3>Extension</h3>
 *

  }

  /** Checks that thread does not terminate within the given millisecond delay. */
  void assertThreadStaysAlive(Thread thread, long millis) {
    try {
      // No need to optimize the failing case via Thread.join.
      delay(millis);
      assertTrue(thread.isAlive());
    } catch (InterruptedException ie) {
      fail("Unexpected InterruptedException");
    }
  }

  /**

 * randomly ordered data (the probability decreases faster than exponentially in N), but if you are
 * passing in unsanitized user data then a malicious user could force it. A light shuffle of the
 * data using an unpredictable seed should normally be enough to thwart this attack.
 *
 * <p>The time taken to compute multiple quantiles on the same dataset using {@link Scale#indexes

   * with the UTF-8 character encoding. The caller is responsible for <a
   * href="https://goo.gl/9EfkM1">replacing any unpaired carriage return or line feed characters
   * with a CR+LF pair</a> on any non-file inputs before escaping them with this escaper.
   *
   * <p>When escaping a String, the following rules apply:
   *
   * <ul>

    Runnable submittedTask;
    long oldRunCount;
    synchronized (queue) {
      // If the worker is already running (or execute() on the delegate returned successfully, and
      // the worker has yet to start) then we don't need to start the worker.
      if (workerRunningState == RUNNING || workerRunningState == QUEUED) {
        queue.add(task);
        return;
      }

      oldRunCount = workerRunCount;