### Question:
CellEditorControlsViewImpl implements CellEditorControlsView { void removeOnClosedByKeyboardCallback(final PopupEditorControls editor) { if (editor instanceof CanBeClosedByKeyboard) { ((CanBeClosedByKeyboard) editor).setOnClosedByKeyboardCallback(null); } } CellEditorControlsViewImpl(); @Inject  CellEditorControlsViewImpl(final Document document,
                                      final Div cellEditorControls,
                                      final Div cellEditorControlsContainer); Optional<PopupEditorControls> getActiveEditor(); void setActiveEditor(final Optional<PopupEditorControls> activeEditor); @PostConstruct void setup(); @PreDestroy void destroy(); @Override void show(final PopupEditorControls editor,
                     final int x,
                     final int y); @Override void hide(); static final String LEFT; static final String TOP; }### Answer:
@Test public void testRemoveOnClosedByKeyboardCallback() { final PopupEditorControls editor = mock(PopupEditorControls.class, withSettings().extraInterfaces(CanBeClosedByKeyboard.class)); view.removeOnClosedByKeyboardCallback(editor); verify((CanBeClosedByKeyboard) editor).setOnClosedByKeyboardCallback(null); }