final FBFormItem formItem = EasyMock.createMock(FBFormItem.class);
final Map<String, Object> oldProps = new HashMap<String, Object>();
final Map<String, Object> newProps = new HashMap<String, Object>();
UndoableHandler handler = EasyMock.createMock(UndoableHandler.class);
handler.onEvent(EasyMock.isA(UndoableEvent.class));
EasyMock.expectLastCall().andAnswer(new IAnswer<Object>() {
public Object answer() throws Throwable {
Object[] params = EasyMock.getCurrentArguments();
UndoableEvent event = (UndoableEvent) params[0];
assertNotNull("oldItems shouldn't be null", event.getData("oldItems"));