### Question:
DataTypeListItemView implements DataTypeListItem.View { @Override public void showEditButton() { show(getEditButton()); show(getAddDataTypeRowButton()); show(getRemoveButton()); hide(getSaveButton()); hide(getCloseButton()); } @Inject  DataTypeListItemView(final HTMLDivElement view,
                                final TranslationService translationService,
                                final @DMNEditor ReadOnlyProvider readOnlyProvider); @Override void init(final DataTypeListItem presenter); @Override HTMLElement getElement(); @Override void toggleArrow(final boolean show); @Override void expand(); @Override void collapse(); @Override void showEditButton(); @Override void showSaveButton(); @Override void enableFocusMode(); @Override void disableFocusMode(); @Override boolean isOnFocusMode(); @Override String getName(); @Override void setName(final String name); @Override void showDataTypeNameInput(); @Override void hideDataTypeNameInput(); @Override void setupSelectComponent(final DataTypeSelect typeSelect); @Override void setupConstraintComponent(final DataTypeConstraint dataTypeConstraintComponent); @Override void setupListComponent(final SmallSwitchComponent dataTypeListComponent); @Override void showListContainer(); @Override void hideListContainer(); @Override void showListYesLabel(); @Override void hideListYesLabel(); @Override boolean isCollapsed(); @Override void setDataType(final DataType dataType); static final String UUID_ATTR; static final String NAME_DATA_FIELD; static final String PARENT_UUID_ATTR; }### Answer:
@Test public void testShowEditButton() { editButton.classList = mock(DOMTokenList.class); addDataTypeRow.classList = mock(DOMTokenList.class); removeButton.classList = mock(DOMTokenList.class); saveButton.classList = mock(DOMTokenList.class); closeButton.classList = mock(DOMTokenList.class); doReturn(editButton).when(view).getEditButton(); doReturn(addDataTypeRow).when(view).getAddDataTypeRowButton(); doReturn(removeButton).when(view).getRemoveButton(); doReturn(saveButton).when(view).getSaveButton(); doReturn(closeButton).when(view).getCloseButton(); view.showEditButton(); verify(editButton.classList).remove(HIDDEN_CSS_CLASS); verify(addDataTypeRow.classList).remove(HIDDEN_CSS_CLASS); verify(removeButton.classList).remove(HIDDEN_CSS_CLASS); verify(saveButton.classList).add(HIDDEN_CSS_CLASS); verify(closeButton.classList).add(HIDDEN_CSS_CLASS); }