AlterTest.php

<?php

declare (strict_types=1);
namespace Drupal\Tests\system\Kernel\Common;

use Drupal\KernelTests\KernelTestBase;

/**
 * Tests alteration of arguments passed to \Drupal::moduleHandler->alter().
 *
 * @group Common
 */
class AlterTest extends KernelTestBase {
    
    /**
     * {@inheritdoc}
     */
    protected static $modules = [
        'block',
        'common_test',
        'system',
    ];
    
    /**
     * Tests if the theme has been altered.
     */
    public function testDrupalAlter() : void {
        // This test depends on Olivero, so make sure that it is always the current
        // active theme.
        \Drupal::service('theme_installer')->install([
            'olivero',
        ]);
        \Drupal::theme()->setActiveTheme(\Drupal::service('theme.initialization')->initTheme('olivero'));
        $array = [
            'foo' => 'bar',
        ];
        $entity = new \stdClass();
        $entity->foo = 'bar';
        // Verify alteration of a single argument.
        $array_copy = $array;
        $array_expected = [
            'foo' => 'Drupal theme',
        ];
        \Drupal::moduleHandler()->alter('drupal_alter', $array_copy);
        \Drupal::theme()->alter('drupal_alter', $array_copy);
        $this->assertEquals($array_expected, $array_copy, 'Single array was altered.');
        $entity_copy = clone $entity;
        $entity_expected = clone $entity;
        $entity_expected->foo = 'Drupal theme';
        \Drupal::moduleHandler()->alter('drupal_alter', $entity_copy);
        \Drupal::theme()->alter('drupal_alter', $entity_copy);
        $this->assertEquals($entity_expected, $entity_copy, 'Single object was altered.');
        // Verify alteration of multiple arguments.
        $array_copy = $array;
        $entity_copy = clone $entity;
        $entity_expected = clone $entity;
        $entity_expected->foo = 'Drupal theme';
        $array2_copy = $array;
        $array2_expected = [
            'foo' => 'Drupal theme',
        ];
        \Drupal::moduleHandler()->alter('drupal_alter', $array_copy, $entity_copy, $array2_copy);
        \Drupal::theme()->alter('drupal_alter', $array_copy, $entity_copy, $array2_copy);
        $this->assertEquals($array_expected, $array_copy, 'First argument to \\Drupal::moduleHandler->alter() was altered.');
        $this->assertEquals($entity_expected, $entity_copy, 'Second argument to \\Drupal::moduleHandler->alter() was altered.');
        $this->assertEquals($array2_expected, $array2_copy, 'Third argument to \\Drupal::moduleHandler->alter() was altered.');
        // Verify alteration order when passing an array of types to \Drupal::moduleHandler->alter().
        // common_test_module_implements_alter() places 'block' implementation after
        // other modules.
        $array_copy = $array;
        $array_expected = [
            'foo' => 'Drupal block theme',
        ];
        \Drupal::moduleHandler()->alter([
            'drupal_alter',
            'drupal_alter_foo',
        ], $array_copy);
        \Drupal::theme()->alter([
            'drupal_alter',
            'drupal_alter_foo',
        ], $array_copy);
        $this->assertEquals($array_expected, $array_copy, 'hook_TYPE_alter() implementations ran in correct order.');
    }

}