@TestOnly
  void assertNoReferencesKept(@NotNull Disposable aDisposable) {
    assert getObject() != aDisposable;
    for (ObjectNode node : myChildren.getAllNodes()) {
      node.assertNoReferencesKept(aDisposable);
    }
  }
@TestOnly
  void assertNoReferencesKept(@NotNull Disposable aDisposable)