Reduced the number of function calls required for .find() (single element root),...

diff --git a/src/core.js b/src/core.js
index a9e7536..a67b5f0 100644 (file)
--- a/src/core.js
+++ b/src/core.js
@@ -22,7 +22,16 @@ var
 jQuery.fn = jQuery.prototype = {
        init: function( selector, context ) {
                // Make sure that a selection was provided
-               selector = selector || document;
+               if ( selector === undefined ) {
+                       selector = document;
+               }
+
+               // Handle "", null
+               if ( !selector ) {
+                       this.length = 0;
+                       this.context = document;
+                       return this;
+               }
 
                // Handle $(DOMElement)
                if ( selector.nodeType ) {
@@ -31,6 +40,7 @@ jQuery.fn = jQuery.prototype = {
                        this.context = selector;
                        return this;
                }
+
                // Handle HTML strings
                if ( typeof selector === "string" ) {
                        // Are we dealing with HTML string or an ID?
@@ -40,17 +50,18 @@ jQuery.fn = jQuery.prototype = {
                        if ( match && (match[1] || !context) ) {
 
                                // HANDLE: $(html) -> $(array)
-                               if ( match[1] )
+                               if ( match[1] ) {
                                        selector = jQuery.clean( [ match[1] ], context );
 
                                // HANDLE: $("#id")
-                               else {
+                               } else {
                                        var elem = document.getElementById( match[3] );
 
                                        // Handle the case where IE and Opera return items
                                        // by name instead of ID
-                                       if ( elem && elem.id != match[3] )
+                                       if ( elem && elem.id != match[3] ) {
                                                return jQuery().find( selector );
+                                       }
 
                                        // Otherwise, we inject the element directly into the jQuery object
                                        var ret = jQuery( elem || [] );
@@ -61,13 +72,21 @@ jQuery.fn = jQuery.prototype = {
 
                        // HANDLE: $(expr, [context])
                        // (which is just equivalent to: $(content).find(expr)
-                       } else
-                               return jQuery( context ).find( selector );
+                       } else if ( !context || context.nodeType ) {
+                               this[0] = context || document;
+                               this.length = 1;
+                               this.context = context;
+                               return this.find( selector );
+
+                       } else {
+                               return (context.jquery ? context : jQuery( context )).find( selector );
+                       }
 
                // HANDLE: $(function)
                // Shortcut for document ready
-               } else if ( jQuery.isFunction( selector ) )
+               } else if ( jQuery.isFunction( selector ) ) {
                        return jQuery( document ).ready( selector );
+               }
 
                // Make sure that old selector state is passed along
                if ( selector.selector && selector.context ) {
@@ -274,8 +293,7 @@ jQuery.fn = jQuery.prototype = {
 
        find: function( selector ) {
                if ( this.length === 1 ) {
-                       var ret = this.pushStack( [], "find", selector );
-                       ret.length = 0;
+                       var ret = this.pushStack( "", "find", selector );
                        jQuery.find( selector, this[0], ret );
                        return ret;
                } else {