@Test
  public void testClone() {
    graph = createGraph();
    graph.edge(1, 2, 10, true);
    NodeAccess na = graph.getNodeAccess();
    na.setNode(0, 12, 23);
    na.setNode(1, 8, 13);
    na.setNode(2, 2, 10);
    na.setNode(3, 5, 9);
    graph.edge(1, 3, 10, true);

    Graph clone = graph.copyTo(createGraph(locationParent + "/clone", false));
    assertEquals(graph.getNodes(), clone.getNodes());
    assertEquals(
        count(carOutExplorer.setBaseNode(1)),
        count(clone.createEdgeExplorer(carOutFilter).setBaseNode(1)));
    clone.edge(1, 4, 10, true);
    assertEquals(3, count(clone.createEdgeExplorer(carOutFilter).setBaseNode(1)));
    assertEquals(graph.getBounds(), clone.getBounds());
    Helper.close((Closeable) clone);
  }