}

  @JsFunction
  interface IThenOnRejectedCallbackFn<V extends @Nullable Object> {
    V onInvoke(Object p0);
  }
}

/** Subset of the elemental2 Promise API. */
@JsType(isNative = true, namespace = JsPackage.GLOBAL, name = "Promise")
class Promise<T extends @Nullable Object> implements IThenable<T> {

  @JsFunction
  interface PromiseExecutorCallbackFn<T extends @Nullable Object> {
    @JsFunction

       * we're copying into a `contents` array whose type allows it to contain nulls. Still, it's
       * worth noting that we promise not to put nulls into the array in the first `size` elements.
       * We uphold that promise here because our callers promise that `elements` will not contain
       * nulls in its first `n` elements.
       */
      System.arraycopy(elements, 0, contents, size, n);
      size += n;

       * we're copying into a `contents` array whose type allows it to contain nulls. Still, it's
       * worth noting that we promise not to put nulls into the array in the first `size` elements.
       * We uphold that promise here because our callers promise that `elements` will not contain
       * nulls in its first `n` elements.
       */
      System.arraycopy(elements, 0, contents, size, n);
      size += n;

  }

  public void testPowerSetIteration_manual() {
    ImmutableSet<Integer> elements = ImmutableSet.of(1, 2, 3);
    Set<Set<Integer>> powerSet = powerSet(elements);
    // The API doesn't promise this iteration order, but it's convenient here.
    Iterator<Set<Integer>> i = powerSet.iterator();
    assertEquals(ImmutableSet.of(), i.next());
    assertEquals(ImmutableSet.of(1), i.next());

            // callable actually completes. (We could detect completion in our wrapper
            // `AsyncCallable task`.) However, our contract also promises:
            //
            // 2. not to cancel any Future the user returned from an AsyncCallable
            //
            // We promise this because, once we cancel that Future, we would no longer be able to

        Iterable<?> locks2 = striped.bulkGet(objects);
        assertEquals(Lists.newArrayList(locks), Lists.newArrayList(locks2));
      }
    }
  }

  /** Checks idempotency, and that we observe the promised number of stripes. */
  public void testBasicInvariants() {
    for (Striped<?> striped : allImplementations()) {
      assertBasicInvariants(striped);
    }
  }

        Arrays.asList(1, 2, 3, 4, 5),
        Ordering.<Integer>natural().leastOf(list.iterator(), Integer.MAX_VALUE));
  }

  public void testGreatestOfIterable_simple() {
    /*
     * If greatestOf() promised to be implemented as reverse().leastOf(), this
     * test would be enough. It doesn't... but we'll cheat and act like it does
     * anyway. There's a comment there to remind us to fix this if we change it.
     */

        Arrays.asList(1, 2, 3, 4, 5),
        Ordering.<Integer>natural().leastOf(list.iterator(), Integer.MAX_VALUE));
  }

  public void testGreatestOfIterable_simple() {
    /*
     * If greatestOf() promised to be implemented as reverse().leastOf(), this
     * test would be enough. It doesn't... but we'll cheat and act like it does
     * anyway. There's a comment there to remind us to fix this if we change it.
     */

  }

  public void testFromNullable() {
    Optional<String> optionalName = Optional.fromNullable("bob");
    assertEquals("bob", optionalName.get());
  }

  public void testFromNullable_null() {
    // not promised by spec, but easier to test
    assertSame(Optional.absent(), Optional.fromNullable(null));
  }

  public void testIsPresent_no() {
    assertFalse(Optional.absent().isPresent());
  }

        Iterable<?> locks2 = striped.bulkGet(objects);
        assertEquals(Lists.newArrayList(locks), Lists.newArrayList(locks2));
      }
    }
  }

  /** Checks idempotency, and that we observe the promised number of stripes. */
  public void testBasicInvariants() {
    for (Striped<?> striped : allImplementations()) {
      assertBasicInvariants(striped);
    }
  }