}

  private boolean runCollectionTests = true;

  /**
   * Specify whether to skip the general collection tests. Call this method when testing a
   * collection that's both a queue and a list, to avoid running the common collection tests twice.
   * By default, collection tests do run.
   */
  @CanIgnoreReturnValue
  public QueueTestSuiteBuilder<E> skipCollectionTests() {

  /**
   * Returns the set of values that are contained in both this set and the other.
   *
   * <p>This method should always be used instead of {@link Sets#intersection} for {@link
   * ContiguousSet} instances.
   */
  public abstract ContiguousSet<C> intersection(ContiguousSet<C> other);

  /**
   * Returns a range, closed on both ends, whose endpoints are the minimum and maximum values

    assertThrows(IllegalArgumentException.class, () -> DoubleUtils.ensureNonNegative(Double.NaN));
  }

  public void testOneBits() {
    assertEquals(DoubleUtils.ONE_BITS, Double.doubleToRawLongBits(1.0));
  }

  private static void failFormat(String template, Object... args) {
    fail(String.format(template, args));
  }

   * default rounding mode: if the two nearest representable values are equally near, the one with
   * the least significant bit zero is chosen. (In such cases, both of the nearest representable
   * values are even integers; this method returns the one that is a multiple of a greater power of
   * two.)
   *

 * @param <V> Value parameter type
 */
@ElementTypesAreNonnullByDefault
final class DirectedGraphConnections<N, V> implements GraphConnections<N, V> {
  /**
   * A wrapper class to indicate a node is both a predecessor and successor while still providing
   * the successor value.
   */
  private static final class PredAndSucc {
    private final Object successorValue;

    PredAndSucc(Object successorValue) {

    } catch (IllegalStateException expected) {
    }
  }

  // Technically we should test other reentrant scenarios (4 combinations of
  // hasNext/next), but we'll cop out for now, knowing that
  // next() both start by invoking hasNext() anyway.

  /** Throws an undeclared checked exception. */
  private static void sneakyThrow(Throwable t) {
    class SneakyThrower<T extends Throwable> {

    ExecutorService exec = Executors.newCachedThreadPool();

    int listenerCount = 20;
    CountDownLatch listenerLatch = new CountDownLatch(listenerCount);

    // Test that listeners added both before and after the value is available
    // get called correctly.
    for (int i = 0; i < 20; i++) {

      // Right in the middle start up a thread to close the latch.
      if (i == 10) {

    } catch (IllegalStateException expected) {
    }
  }

  // Technically we should test other reentrant scenarios (4 combinations of
  // hasNext/next), but we'll cop out for now, knowing that
  // next() both start by invoking hasNext() anyway.

  /** Throws an undeclared checked exception. */
  private static void sneakyThrow(Throwable t) {
    class SneakyThrower<T extends Throwable> {

    String safeInput = "\uD800\uDC00"; // 0x10000
    assertEquals(safeInput, surrogateEscaper.escape(safeInput));

    // A surrogate pair defining a code point outside the safe range (but both
    // of the surrogate characters lie within the safe range). It is important
    // not to accidentally treat this as a sequence of safe characters.
    String unsafeInput = "\uDBFF\uDFFF"; // 0x10FFFF

      canRemove = false;
      expectedModCount++;
      if (cursor < size()) {
        MoveDesc<E> moved = removeAt(cursor);
        if (moved != null) {
          // Either both are null or neither is, but we check both to satisfy the nullness checker.
          if (forgetMeNot == null || skipMe == null) {
            forgetMeNot = new ArrayDeque<>();
            skipMe = new ArrayList<>(3);
          }