ChooseRunnerAction extends AbstractRunnerActions implements CustomComponentAction { public void setEmptyDefaultRunner() { dropDownHeaderWidget.selectElement(null, ""); } @Inject  ChooseRunnerAction(RunnerResources resources,
                              RunnerLocalizationConstant locale,
                              AppContext appContext,
                              ActionManager actionManager,
                              DropDownListFactory dropDownListFactory); @Override void actionPerformed(ActionEvent e); @Override Widget createCustomComponent(Presentation presentation); void addSystemRunners(@NotNull List<Environment> systemEnvironments); void addProjectRunners(@NotNull List<Environment> projectEnvironments); @Nullable Environment selectEnvironment(); void selectDefaultRunner(); void setEmptyDefaultRunner();  }
@Test public void emptyDefaultRunnerShouldBeSet() throws Exception { action.setEmptyDefaultRunner(); verify(dropDownHeaderWidget).selectElement(null, ""); }