ClaroTableTest.php

<?php

namespace Drupal\KernelTests\Core\Theme;

use Drupal\KernelTests\KernelTestBase;

/**
 * Tests Claro specific table functionality.
 *
 * @group Theme
 */
class ClaroTableTest extends KernelTestBase {
    
    /**
     * {@inheritdoc}
     */
    protected static $modules = [
        'system',
    ];
    
    /**
     * Confirm that Claro tables override use of the `sticky-enabled` class.
     */
    public function testThemeTableStickyHeaders() {
        // Enable the Claro theme.
        \Drupal::service('theme_installer')->install([
            'claro',
        ]);
        $this->config('system.theme')
            ->set('default', 'claro')
            ->save();
        $header = [
            'one',
            'two',
            'three',
        ];
        $rows = [
            [
                1,
                2,
                3,
            ],
            [
                4,
                5,
                6,
            ],
            [
                7,
                8,
                9,
            ],
        ];
        $table = [
            '#type' => 'table',
            '#header' => $header,
            '#rows' => $rows,
            '#sticky' => TRUE,
        ];
        $this->render($table);
        // Confirm that position-sticky is used instead of sticky-enabled.
        $this->assertNoRaw('sticky-enabled');
        $this->assertRaw('position-sticky');
    }

}