Plugin Factory validatePluginInfoElement

gistfile1.aw

<?php
  /**
   * Validate that the plugin info array contains the all of the required keys
   *
   * @param $plugin_info
   * @param $element_key
   * @param $element
   *
   * @throws Exception\InvalidPluginException
   *
   *
   * @return \Drupal\sps\PluginFactory
   *  self
   */
  protected function validatePluginInfoElement($plugin_info, $element_key, $element) {
    if (is_array($element)) {
      if (!isset($plugin_info[$element_key])) {
        throw new InvalidPluginException(
          "Plugin {$plugin_info['name']} does not contain required element $element_key");
      }
    }
    else {
      if (!isset($plugin_info[$element])) {
        throw new InvalidPluginException(
          "Plugin {$plugin_info['name']} does not contain required element $element");
      }
    }

    return $this;
  }

So I am thining that this function does not do what it is suppose to do, but I want to see if you had any idea on what it might be trying to do?