@Test
public void aspectFiredAfterNodeExpand() {

  DefaultMutableTreeNode root = (DefaultMutableTreeNode)myModel.getRoot();
  AspectObserver observer = new AspectObserver();
  int[] treeModelChangeCount = new int[]{0};
  myModel.getAspect().addDependency(observer).onChange(CpuTreeModel.Aspect.TREE_MODEL, () -> ++treeModelChangeCount[0]);
  assertThat(treeModelChangeCount[0]).isEqualTo(0);
  myModel.expand(findNodeOnPath(root, "Root", "B"));
  assertThat(treeModelChangeCount[0]).isEqualTo(1);
}