function user_system_info_alter in Drupal 7

Implements hook_system_info_alter().

Drupal 7 ships with two methods to add additional fields to users: Profile module, a legacy module dating back from 2002, and Field API integration with users. While Field API support for users currently provides less end user features, the inefficient data storage mechanism of Profile module, as well as its lack of consistency with the rest of the entity / field based systems in Drupal 7, make this a sub-optimal solution to those who were not using it in previous releases of Drupal.

To prevent new Drupal 7 sites from installing Profile module, and unwittingly ending up with two completely different and incompatible methods of extending users, only make the Profile module available if the profile_* tables are present.

@todo: Remove in D8, pending upgrade path.

File

modules/user/user.module, line 4104

Enables the user registration and login system.

Code

function user_system_info_alter(&$info, $file, $type) {
  if ($type == 'module' && $file->name == 'profile' && db_table_exists('profile_field')) {
    $info['hidden'] = FALSE;
  }
}