drupal_routes/sites/all/modules/contrib/leaflet/leaflet.install

<?php

/**
 * @file
 * Install, update, and uninstall functions for the leaflet module.
 */

/**
 * Implements hook_requirements().
 */
function leaflet_requirements($phase) {
  $requirements = array();
  $t = get_t();

  // Verify the Leaflet library is installed correctly.
  if (in_array($phase, array('runtime', 'update'))) {
    $library = libraries_detect('leaflet');
    $requirements['leaflet'] = array(
      'title' => $t('Leaflet'),
    );

    if ($library['installed']) {
      $requirements['leaflet'] += array(
        'value' => $library['version'],
        'description' => t('The Leaflet Javascript library is installed correctly. @maps available.', array(
          '@maps' => format_plural(count(leaflet_map_get_info()),'One map', '@count maps'))),
        'severity' => REQUIREMENT_OK,
      );
    }
    else {
      $requirements['leaflet'] += array(
        'value' => $library['error'],
        'description' => $library['error message'],
        'severity' => REQUIREMENT_ERROR,
      );
    }
  }

  return $requirements;
}