Fixed #1727 bug where :nth-child() was non-standard with CSS3 plus two minor white...

[jquery.git] / src / selector.js

diff --git a/src/selector.js b/src/selector.js
index 82627e1..b272acd 100644 (file)
--- a/src/selector.js
+++ b/src/selector.js
@@ -192,7 +192,7 @@ jQuery.extend({
                                        
                                        // Re-organize the results, so that they're consistent
                                        if ( m ) {
-                                          m = [ 0, m[2], m[3], m[1] ];
+                                               m = [ 0, m[2], m[3], m[1] ];
 
                                        } else {
                                                // Otherwise, do a traditional filter check for
@@ -297,7 +297,7 @@ jQuery.extend({
                var last;
 
                // Look for common filter expressions
-               while ( t  && t != last ) {
+               while ( t && t != last ) {
                        last = t;
 
                        var p = jQuery.parse, m;
@@ -349,11 +349,14 @@ jQuery.extend({
                        // We can get a speed boost by handling nth-child here
                        } else if ( m[1] == ":" && m[2] == "nth-child" ) {
                                var merge = {}, tmp = [],
-                                       test = /(\d*)n\+?(\d*)/.exec(
+                                       // parse equations like 'even', 'odd', '5', '2n', '3n+2', '4n-1', '-n+6'
+                                       test = /(-?)(\d*)n((?:\+|-)?\d*)/.exec(
                                                m[3] == "even" && "2n" || m[3] == "odd" && "2n+1" ||
-                                               !/\D/.test(m[3]) && "n+" + m[3] || m[3]),
-                                       first = (test[1] || 1) - 0, last = test[2] - 0;
-
+                                               !/\D/.test(m[3]) && "0n+" + m[3] || m[3]),
+                                       // calculate the numbers (first)n+(last) including if they are negative
+                                       first = (test[1] + (test[2] || 1)) - 0, last = test[3] - 0;
+ 
+                               // loop through all the elements left in the jQuery object
                                for ( var i = 0, rl = r.length; i < rl; i++ ) {
                                        var node = r[i], parentNode = node.parentNode, id = jQuery.data(parentNode);
 
@@ -369,10 +372,10 @@ jQuery.extend({
 
                                        var add = false;
 
-                                       if ( first == 1 ) {
-                                               if ( last == 0 || node.nodeIndex == last )
+                                       if ( first == 0 ) {
+                                               if ( node.nodeIndex == last )
                                                        add = true;
-                                       } else if ( (node.nodeIndex + last) % first == 0 )
+                                       } else if ( (node.nodeIndex - last) % first == 0 && (node.nodeIndex - last) / first >= 0 )
                                                add = true;
 
                                        if ( add ^ not )