Reset Roles (or undo role changes on theme change)

Question

I am creating a theme that deletes some user roles that are not necessary and creates others. (It deletes author and contributor and renames subscriber).

Everything works, but on theme deactivation, I want to readd all the roles I deleted. Do I have to manually go in and create the roles (author and contributor), manually adding in all the capabilities listed here: http://codex.wordpress.org/Roles_and_Capabilities ?

There are two reasons I don't want to do this:

1. More code.
2. If capabilities and roles get updated, on every Wordpress update I'll have to manually check I'm adding the right capabilities back.

There must be a better solution for undoing all role changes I made on deactivation. Right?

Answer 1

Use a plugin to manage roles, not a theme. Roles are not for presentation.

In your plugin use register_activation_hook() and register_deactivation_hook() to add or remove new roles. Do not remove built-in roles, other plugins may rely on their existence.

Answer 2

The following code will reset a WordPress default role to it's default capabilities. Note: these defaults are for WordPress 3.5, any other versions might have different defaults. To be safe, only use this code on WordPress 3.5.

Warning

This cannot be undone! The role, in it's current state, is removed and recreated with it's default values.

/*
 * example usage: $results = reset_role_wpse_82378( 'subscriber' );
 * per add_role() (WordPress Codex):
 * $results "Returns a WP_Role object on success, null if that role already exists."
 *
 * possible $role values:
 * 'administrator'
 * 'editor'
 * 'author'
 * 'contributor'
 * 'subscriber'
 */
function reset_role_wpse_82378( $role ) {
    $default_roles = array(
        'administrator' => array(
            'switch_themes' => 1,
            'edit_themes' => 1,
            'activate_plugins' => 1,
            'edit_plugins' => 1,
            'edit_users' => 1,
            'edit_files' => 1,
            'manage_options' => 1,
            'moderate_comments' => 1,
            'manage_categories' => 1,
            'manage_links' => 1,
            'upload_files' => 1,
            'import' => 1,
            'unfiltered_html' => 1,
            'edit_posts' => 1,
            'edit_others_posts' => 1,
            'edit_published_posts' => 1,
            'publish_posts' => 1,
            'edit_pages' => 1,
            'read' => 1,
            'level_10' => 1,
            'level_9' => 1,
            'level_8' => 1,
            'level_7' => 1,
            'level_6' => 1,
            'level_5' => 1,
            'level_4' => 1,
            'level_3' => 1,
            'level_2' => 1,
            'level_1' => 1,
            'level_0' => 1,
            'edit_others_pages' => 1,
            'edit_published_pages' => 1,
            'publish_pages' => 1,
            'delete_pages' => 1,
            'delete_others_pages' => 1,
            'delete_published_pages' => 1,
            'delete_posts' => 1,
            'delete_others_posts' => 1,
            'delete_published_posts' => 1,
            'delete_private_posts' => 1,
            'edit_private_posts' => 1,
            'read_private_posts' => 1,
            'delete_private_pages' => 1,
            'edit_private_pages' => 1,
            'read_private_pages' => 1,
            'delete_users' => 1,
            'create_users' => 1,
            'unfiltered_upload' => 1,
            'edit_dashboard' => 1,
            'update_plugins' => 1,
            'delete_plugins' => 1,
            'install_plugins' => 1,
            'update_themes' => 1,
            'install_themes' => 1,
            'update_core' => 1,
            'list_users' => 1,
            'remove_users' => 1,
            'add_users' => 1,
            'promote_users' => 1,
            'edit_theme_options' => 1,
            'delete_themes' => 1,
            'export' => 1,
        ),
        'editor' => array(
            'moderate_comments' => 1,
            'manage_categories' => 1,
            'manage_links' => 1,
            'upload_files' => 1,
            'unfiltered_html' => 1,
            'edit_posts' => 1,
            'edit_others_posts' => 1,
            'edit_published_posts' => 1,
            'publish_posts' => 1,
            'edit_pages' => 1,
            'read' => 1,
            'level_7' => 1,
            'level_6' => 1,
            'level_5' => 1,
            'level_4' => 1,
            'level_3' => 1,
            'level_2' => 1,
            'level_1' => 1,
            'level_0' => 1,
            'edit_others_pages' => 1,
            'edit_published_pages' => 1,
            'publish_pages' => 1,
            'delete_pages' => 1,
            'delete_others_pages' => 1,
            'delete_published_pages' => 1,
            'delete_posts' => 1,
            'delete_others_posts' => 1,
            'delete_published_posts' => 1,
            'delete_private_posts' => 1,
            'edit_private_posts' => 1,
            'read_private_posts' => 1,
            'delete_private_pages' => 1,
            'edit_private_pages' => 1,
            'read_private_pages' => 1,
        ),
        'author' => array(
            'upload_files' => 1,
            'edit_posts' => 1,
            'edit_published_posts' => 1,
            'publish_posts' => 1,
            'read' => 1,
            'level_2' => 1,
            'level_1' => 1,
            'level_0' => 1,
            'delete_posts' => 1,
            'delete_published_posts' => 1,
        ),
        'contributor' => array(
            'edit_posts' => 1,
            'read' => 1,
            'level_1' => 1,
            'level_0' => 1,
            'delete_posts' => 1,
        ),
        'subscriber' => array(
            'read' => 1,
            'level_0' => 1,
        ),
        'display_name' => array(
            'administrator' => 'Administrator',
            'editor'        => 'Editor',
            'author'        => 'Author',
            'contributor'   => 'Contributor',
            'subscriber'    => 'Subscriber',
        ),
    );
    $role = strtolower( $role );
    remove_role( $role );
    return add_role( $role, $default_roles['display_name'][$role], $default_roles[$role] );
} // function reset_role_wpse_82378