getExtenders example

/** * Tests display extenders. */
  public function testDisplayExtenders() {
    $this->config('views.settings')->set('display_extenders', ['display_extender_test'])->save();
    $this->assertCount(1, Views::getEnabledDisplayExtenders(), 'Make sure that there is only one enabled display extender.');

    $view = Views::getView('test_view');
    $view->initDisplay();

    $this->assertCount(1, $view->display_handler->getExtenders(), 'Make sure that only one extender is initialized.');

    $display_extender = $view->display_handler->getExtenders()['display_extender_test'];
    $this->assertInstanceOf(DisplayExtenderTestData::class, $display_extender);

    $view->preExecute();
    $this->assertTrue($display_extender->testState['preExecute'], 'Make sure the display extender was able to react on preExecute.');
    $view->execute();
    $this->assertTrue($display_extender->testState['query'], 'Make sure the display extender was able to react on query.');
  }

  /** * Tests display extenders validation. */