materio-base-d7/modules/system/tests/system_cron_test.module

<?php

/**
 * @file
 * Helper module for CronRunTestCase::testCronCacheExpiration().
 */

/**
 * Implements hook_flush_caches().
 */
function system_cron_test_flush_caches() {
  // Set a variable to indicate that this hook was invoked.
  variable_set('system_cron_test_flush_caches', 1);
  return array();
}