Docs: Improve JSDoc for wp-admin/js/user-suggest.js.

Props timhavinga.
Fixes #43270.


git-svn-id: https://develop.svn.wordpress.org/trunk@42708 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/js/user-suggest.js

@@ -1,4 +1,14 @@
 /* global ajaxurl, current_site_id, isRtl */
+/**
+ * Suggests users in a multisite environment.
+ *
+ * For input fields where the admin can select a user based on email or
+ * username, this script shows an autocompletion menu for these inputs. Should
+ * only be used in a multisite environment. Only users in the currently active
+ * site are shown.
+ *
+ * @since 3.4.0
+ */
 
 (function( $ ) {
 	var id = ( typeof current_site_id !== 'undefined' ) ? '&site_id=' + current_site_id : '';
@@ -8,6 +18,29 @@
 			position.my = 'right top';
 			position.at = 'right bottom';
 		}
+
+		/**
+		 * Adds an autocomplete function to input fields marked with the class
+		 * 'wp-suggest-user'.
+		 *
+		 * A minimum of two characters is required to trigger
+		 * the suggestions. The autocompletion menu is shown at the left bottom of the input
+		 * field. On RTL installations, it is shown at the right top.
+		 * Adds the class 'open' to the input field when the autocompletion menu
+		 * is shown.
+		 *
+		 * Does a backend call to retrieve the users.
+		 *
+		 * Optional data-attributes:
+		 * - data-autocomplete-type (add, search)
+		 *   The action that is going to be performed: search for existing users
+		 *   or add a new one. Default: add
+		 * - data-autocomplete-field (user_login, user_email)
+		 *   The field that is returned as the value for the suggestion.
+		 *   Default: user_login
+		 *
+		 * @see wp-admin/includes/admin-actions.php:wp_ajax_autocomplete_user()
+		 */
 		$( '.wp-suggest-user' ).each( function(){
 			var $this = $( this ),
 				autocompleteType = ( typeof $this.data( 'autocompleteType' ) !== 'undefined' ) ? $this.data( 'autocompleteType' ) : 'add',