### Question:
FeatureActionsMenuProvider implements ContextMenuProvider<DataGroupContextKey> { public DataTypeInfo getDataTypes(DataGroupContextKey key) { Collection<DataTypeInfo> dataTypes = New.list(key.getDataTypes()); key.getDataGroups().stream().filter(Objects::nonNull).forEach(group -> dataTypes.addAll(group.getMembers(false))); for (DataTypeInfo layer : dataTypes) { if (DataTypeChecker.isFeatureType(layer)) { return layer; } } return null; } FeatureActionsMenuProvider(ActionEditorDisplayer displayer, UIRegistry uiRegistry); @Override Collection<? extends Component> getMenuItems(String contextId, DataGroupContextKey key); @Override int getPriority(); Collection<? extends Component> menuItemsForLayer(DataTypeInfo layer); DataTypeInfo getDataTypes(DataGroupContextKey key);  }### Answer:
@Test public void testGroup() { DataTypeInfo tileLayer = new DefaultDataTypeInfo(null, "bla", ourLayerId, ourLayerName, ourLayerName, true); DataGroupInfo group = createDataGroup(tileLayer, ourLayer); FeatureActionsMenuProvider menuProvider = new FeatureActionsMenuProvider(null, null); DataGroupContextKey key = new DataGroupContextKey(group, ourLayer); DataTypeInfo gotLayer = menuProvider.getDataTypes(key); assertEquals(gotLayer, ourLayer); }