ManyAssetsLoadOrderTest.php

<?php

namespace Drupal\FunctionalTests\Libraries;

use Drupal\Tests\BrowserTestBase;

/**
 * Tests the loading of many weighted assets.
 *
 * @group libraries
 */
class ManyAssetsLoadOrderTest extends BrowserTestBase {
    
    /**
     * {@inheritdoc}
     */
    protected $defaultTheme = 'stark';
    
    /**
     * {@inheritdoc}
     */
    protected static $modules = [
        'many_assets_test',
    ];
    
    /**
     * Loads a page with many assets that have different but close weights.
     *
     * Confirms the load order reflects the configured weights for each asset.
     */
    public function testLoadOrder() {
        $this->drupalGet('many_assets_test');
        $js = $this->getSession()
            ->getPage()
            ->findAll('css', 'script[data-weight]');
        $js_files = array_map(function ($item) {
            return $item->getAttribute('data-weight');
        }, $js);
        $this->assertGreaterThan(0, count($js_files));
        $js_files_sorted = $js_files;
        asort($js_files_sorted);
        // If the JavaScript files are loading in the proper order, the sorted array
        // should match the unsorted one.
        $this->assertSame($js_files_sorted, $js_files);
        $css = $this->getSession()
            ->getPage()
            ->findAll('css', 'link[data-weight]');
        $css_files = array_map(function ($item) {
            return $item->getAttribute('data-weight');
        }, $css);
        $this->assertGreaterThan(0, count($css_files));
        $css_files_sorted = $css_files;
        asort($css_files_sorted);
        // If the CSS files are loading in the proper order, the sorted array should
        // match the unsorted one.
        $this->assertSame($css_files_sorted, $css_files);
    }

}