MenuLinkPluginTest.php

<?php

namespace Drupal\Tests\menu_link_content\Unit;

use Drupal\menu_link_content\Plugin\Menu\MenuLinkContent;
use Drupal\Tests\UnitTestCase;

/**
 * @coversDefaultClass \Drupal\menu_link_content\Plugin\Menu\MenuLinkContent
 *
 * @group Menu
 */
class MenuLinkPluginTest extends UnitTestCase {
    
    /**
     * @covers ::getUuid
     */
    public function testGetInstanceReflection() {
        
        /** @var \Drupal\menu_link_content\Plugin\Menu\MenuLinkContent $menu_link_content_plugin */
        $menu_link_content_plugin = $this->prophesize(MenuLinkContent::class);
        $menu_link_content_plugin->getDerivativeId()
            ->willReturn('test_id');
        $menu_link_content_plugin = $menu_link_content_plugin->reveal();
        $class = new \ReflectionClass(MenuLinkContent::class);
        $instance_method = $class->getMethod('getUuid');
        $instance_method->setAccessible(TRUE);
        $this->assertEquals('test_id', $instance_method->invoke($menu_link_content_plugin));
    }

}