plugin_test.module

<?php

/**
 * @file
 * Helper module for the plugin tests.
 */

/**
 * Implements hook_plugin_test_alter().
 */
function plugin_test_plugin_test_alter(&$definitions) {
  foreach ($definitions as &$definition) {
    $definition['altered'] = TRUE;
  }
  $definitions['user_login']['altered_single'] = TRUE;
}