ElementInfoIntegrationTest.php

<?php

namespace Drupal\KernelTests\Core\Render;

use Drupal\KernelTests\KernelTestBase;

/**
 * Tests the element info.
 *
 * @group Render
 */
class ElementInfoIntegrationTest extends KernelTestBase {
  
  /**
   * {@inheritdoc}
   */
  protected function setUp() : void {
    parent::setUp();
    $this->container
      ->get('theme_installer')
      ->install([
      'test_theme',
      'starterkit_theme',
    ]);
  }
  
  /**
   * Ensures that the element info can be altered by themes.
   */
  public function testElementInfoByTheme() {
    /** @var \Drupal\Core\Theme\ThemeInitializationInterface $theme_initializer */
    $theme_initializer = $this->container
      ->get('theme.initialization');
    /** @var \Drupal\Core\Theme\ThemeManagerInterface $theme_manager */
    $theme_manager = $this->container
      ->get('theme.manager');
    /** @var \Drupal\Core\Render\ElementInfoManagerInterface $element_info */
    $element_info = $this->container
      ->get('plugin.manager.element_info');
    $theme_manager->setActiveTheme($theme_initializer->getActiveThemeByName('starterkit_theme'));
    $this->assertEquals(60, $element_info->getInfo('textfield')['#size']);
    $theme_manager->setActiveTheme($theme_initializer->getActiveThemeByName('test_theme'));
    $this->assertEquals(40, $element_info->getInfo('textfield')['#size']);
  }

}