Popsu-coloque/web/core/modules/system/tests/themes/test_subtheme/test_subtheme.theme

<?php

/**
 * @file
 * Add hooks for tests to use.
 */

use Drupal\views\Plugin\views\cache\CachePluginBase;
use Drupal\views\ViewExecutable;

/**
 * Implements hook_views_pre_render().
 */
function test_subtheme_views_pre_render(ViewExecutable $view) {
  // We append the function name to the title for test to check for.
  $view->setTitle($view->getTitle() . ":" . __FUNCTION__);
}

/**
 * Implements hook_views_post_render().
 */
function test_subtheme_views_post_render(ViewExecutable $view, &$output, CachePluginBase $cache) {
  // We append the function name to the title for test to check for.
  $view->setTitle($view->getTitle() . ":" . __FUNCTION__);
  if ($view->id() == 'test_page_display') {
    $output['#rows'][0]['#title'] = t('%total_rows items found.', ['%total_rows' => $view->total_rows]);
  }
}

/**
 * Implements hook_preprocess_HOOK() for theme_test_template_test templates.
 */
function test_subtheme_preprocess_theme_test_template_test(&$variables) {
}