public void testTypingDoesNotInterfereWithDuplicates() throws Exception {
    SliceTreeStructure treeStructure = configureTree("DupSlice");
    SliceNode root = (SliceNode) treeStructure.getRootElement();
    List<SliceNode> nodes = new ArrayList<SliceNode>();
    expandNodesTo(root, nodes);

    for (int i = 0; i < nodes.size() - 1; i++) {
      SliceNode node = nodes.get(i);
      assertNull(node.getDuplicate());
    }
    SliceNode last = nodes.get(nodes.size() - 1);
    assertNotNull(last.getDuplicate());

    type("   xx");
    PsiDocumentManager.getInstance(getProject()).commitAllDocuments();
    backspace();
    backspace();
    PsiDocumentManager.getInstance(getProject()).commitAllDocuments();

    nodes.clear();
    expandNodesTo(root, nodes);
    for (int i = 0; i < nodes.size() - 1; i++) {
      SliceNode node = nodes.get(i);
      assertNull(node.getDuplicate());
    }
    assertNotNull(last.getDuplicate());
  }