List<Editor> editors = newArrayListWithCapacity(original.size());
for (Map.Entry<String, IndexNode> entry : original.entrySet()) {
final String path = entry.getKey();
editors.add(new SubtreeEditor(new DefaultEditor() {
@Override
public void leave(NodeState before, NodeState after) {
try {
// TODO: Use DirectoryReader.openIfChanged()
IndexNode index = IndexNode.open(path, after, cloner);