index now works in reverse when passed a selector or undefined. fixes #3971

[jquery.git] / src / core.js

diff --git a/src/core.js b/src/core.js
index f00d9b0..86c9982 100644 (file)
--- a/src/core.js
+++ b/src/core.js
@@ -182,10 +182,16 @@ jQuery.fn = jQuery.prototype = {
        // Determine the position of an element within
        // the matched set of elements
        index: function( elem ) {
+               if ( !elem || typeof elem === "string" ) {
+                       return jQuery.inArray( this[0],
+                               // If it receives a string, the selector is used
+                               // If it receives nothing, the siblings are used
+                               elem ? jQuery( elem ) : this.parent().children() );
+               }
                // Locate the position of the desired element
                return jQuery.inArray(
                        // If it receives a jQuery object, the first element is used
-                       elem && elem.jquery ? elem[0] : elem, this );
+                       elem.jquery ? elem[0] : elem, this );
        },
 
        is: function( selector ) {
@@ -355,7 +361,7 @@ jQuery.extend({
 
                if ( array != null ) {
                        i = array.length;
-                       
+
                        // The window, strings (and functions) also have 'length'
                        if ( i == null || typeof array === "string" || jQuery.isFunction(array) || array.setInterval ) {
                                ret[0] = array;
@@ -383,7 +389,7 @@ jQuery.extend({
                // We have to loop this way because IE & Opera overwrite the length
                // expando of getElementsByTagName
                var i = 0, elem, pos = first.length;
-               
+
                // Also, we need to make sure that the correct elements are being returned
                // (IE returns comment nodes in a '*' query)
                if ( !jQuery.support.getAll ) {