// void addModelChangeListener(IErlModelChangeListener listener);
// void removeModelChangeListener(IErlModelChangeListener listener);
@Test
public void addModelChangeListener() throws Exception {
final List<IErlElement> changed = Lists.newArrayList();
final IErlModelChangeListener listener = new IErlModelChangeListener() {
@Override
public void elementChanged(final IErlElement element) {
changed.add(element);
}