assertStillOpen(closeable1, closeable2, closeable3);
                    return "value";
                  }
                },
                executor);
    assertThat(getFinalValue(closingFuture)).isEqualTo("value");
    waitUntilClosed(closingFuture);
    assertClosed(closeable1, closeable2);
    assertStillOpen(closeable3);
  }