ManyAssetsTestHooks.php

<?php

declare (strict_types=1);
namespace Drupal\many_assets_test\Hook;

use Drupal\Core\Hook\Attribute\Hook;

/**
 * Hook implementations for many_assets_test.
 */
class ManyAssetsTestHooks {
  
  /**
   * Implements hook_library_info_build().
   */
  public function libraryInfoBuild() : array {
    $libraries = [];
    // Load the local javascript as an "external" asset varied by query string.
    $base_javascript = \Drupal::request()->getBasePath() . '/' . \Drupal::service('extension.list.module')->getPath('many_assets_test') . '/js/noop.js';
    $base_css = \Drupal::request()->getBasePath() . '/' . \Drupal::service('extension.list.module')->getPath('many_assets_test') . '/css/noop.css';
    // Build a library dependency containing 100 javascript assets.
    for ($i = 1; $i <= 150; $i++) {
      $libraries['many-dependencies']['js'][$base_javascript . '?dep' . $i] = [
        'type' => 'external',
      ];
      $libraries['many-dependencies']['css']['component'][$base_css . '?dep' . $i] = [
        'type' => 'external',
      ];
    }
    return $libraries;
  }

}