if (waiter.isAlive()) {
      waiter.interrupt();
      fail("awaitTermination failed to trigger after shutdown()");
    }
  }

  /** Wait for the given thread to reach the {@link State#TIMED_WAITING} thread state. */
  @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
  void awaitTimedWaiting(Thread thread) {
    while (true) {

    if (waiter.isAlive()) {
      waiter.interrupt();
      fail("awaitTermination failed to trigger after shutdown()");
    }
  }

  /** Wait for the given thread to reach the {@link State#TIMED_WAITING} thread state. */
  @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
  void awaitTimedWaiting(Thread thread) {
    while (true) {

        assertThrows(
            TimeoutException.class, () -> service.startAsync().awaitRunning(1, MILLISECONDS));
    assertThat(e)
        .hasMessageThat()
        .isEqualTo("Timed out waiting for Foo [STARTING] to reach the RUNNING state.");
  }

  private class TestService extends AbstractScheduledService {
    final CyclicBarrier runFirstBarrier = new CyclicBarrier(2);
    final CyclicBarrier runSecondBarrier = new CyclicBarrier(2);

        assertThrows(
            TimeoutException.class, () -> service.startAsync().awaitRunning(1, MILLISECONDS));
    assertThat(e)
        .hasMessageThat()
        .isEqualTo("Timed out waiting for Foo [STARTING] to reach the RUNNING state.");
  }

  private class TestService extends AbstractScheduledService {
    final CyclicBarrier runFirstBarrier = new CyclicBarrier(2);
    final CyclicBarrier runSecondBarrier = new CyclicBarrier(2);

        // Will fail due to null user, but verifies depth check passes
        try {
            authenticator.getParentGroup(null, "test-id", 4);
            // If we reach here without NullPointerException, depth check passed
        } catch (NullPointerException e) {
            // Expected due to null user - depth check passed, processing attempted
            assertTrue(true);

            V entryValue = e.getValue();

            if (entryValue != null) {
              // TODO(kak): Remove this branch
            } else if (isCollected(e)) {
              // TODO(kak): Remove this branch
            } else {
              return null;
            }

            ++modCount;
            E newFirst = removeFromChain(first, e);

  public static boolean fuzzyEquals(double a, double b, double tolerance) {
    MathPreconditions.checkNonNegative("tolerance", tolerance);
    return Math.copySign(a - b, 1.0) <= tolerance
        // copySign(x, 1.0) is a branch-free version of abs(x), but with different NaN semantics
        || (a == b) // needed to ensure that infinities equal themselves
        || (Double.isNaN(a) && Double.isNaN(b));
  }

  /**

      KeyList<K, V> keyList = requireNonNull(keyToKeyList.remove(node.getKey()));
      keyList.count = 0;
      modCount++;
    } else {
      // requireNonNull is safe (under the conditions listed in the comment in the branch above).
      KeyList<K, V> keyList = requireNonNull(keyToKeyList.get(node.getKey()));
      keyList.count--;

      if (node.previousSibling == null) {

      KeyList<K, V> keyList = requireNonNull(keyToKeyList.remove(node.getKey()));
      keyList.count = 0;
      modCount++;
    } else {
      // requireNonNull is safe (under the conditions listed in the comment in the branch above).
      KeyList<K, V> keyList = requireNonNull(keyToKeyList.get(node.getKey()));
      keyList.count--;

      if (node.previousSibling == null) {

//
//   - Array: the number of elements in v (same as len(v)).
//   - Pointer to array: the number of elements in *v (same as len(v)).
//   - Slice: the maximum length the slice can reach when resliced;
//     if v is nil, cap(v) is zero.
//   - Channel: the channel buffer capacity, in units of elements;
//     if v is nil, cap(v) is zero.
//