    // @tag dom,core
    /**
     */
    Ext.define('Ext.dom.AbstractElement_traversal', {
        override: 'Ext.dom.AbstractElement',

        /**
         * Looks at this node and then at parent nodes for a match of the passed simple selector (e.g. div.some-class or span:first-child)
         * @param {String} selector The simple selector to test
         * @param {Number/String/HTMLElement/Ext.Element} [limit]
         * The max depth to search as a number or an element which causes the upward traversal to stop
         * and is <b>not</b> considered for inclusion as the result. (defaults to 50 || document.documentElement)
         * @param {Boolean} [returnEl=false] True to return a Ext.Element object instead of DOM node
         * @return {HTMLElement} The matching DOM node (or null if no match was found)
         */
        findParent: function(simpleSelector, limit, returnEl) {
            var target = this.dom,
                topmost = document.documentElement,
                depth = 0,
                stopEl;

            limit = limit || 50;
            if (isNaN(limit)) {
                stopEl = Ext.getDom(limit);
                limit = Number.MAX_VALUE;
            }
            while (target && target.nodeType == 1 && depth < limit && target != topmost && target != stopEl) {
                if (Ext.DomQuery.is(target, simpleSelector)) {
                    return returnEl ? Ext.get(target) : target;
                }
                depth++;
                target = target.parentNode;
            }
            return null;
        },

        /**
         * Looks at parent nodes for a match of the passed simple selector (e.g. div.some-class or span:first-child)
         * @param {String} selector The simple selector to test
         * @param {Number/String/HTMLElement/Ext.Element} [limit]
         * The max depth to search as a number or an element which causes the upward traversal to stop
         * and is <b>not</b> considered for inclusion as the result. (defaults to 50 || document.documentElement)
         * @param {Boolean} [returnEl=false] True to return a Ext.Element object instead of DOM node
         * @return {HTMLElement} The matching DOM node (or null if no match was found)
         */
        findParentNode: function(simpleSelector, limit, returnEl) {
            var p = Ext.fly(this.dom.parentNode, '_internal');
            return p ? p.findParent(simpleSelector, limit, returnEl) : null;
        },

        /**
         * Walks up the DOM looking for a parent node that matches the passed simple selector (e.g. div.some-class or span:first-child).
         * This is a shortcut for findParentNode() that always returns an Ext.dom.Element.
         * @param {String} selector The simple selector to test
         * @param {Number/String/HTMLElement/Ext.Element} [limit]
         * The max depth to search as a number or an element which causes the upward traversal to stop
         * and is <b>not</b> considered for inclusion as the result. (defaults to 50 || document.documentElement)
         * @param {Boolean} [returnDom=false] True to return the DOM node instead of Ext.dom.Element
         * @return {Ext.Element} The matching DOM node (or null if no match was found)
         */
        up: function(simpleSelector, limit, returnDom) {
            return this.findParentNode(simpleSelector, limit, !returnDom);
        },

        /**
         * Creates a {@link Ext.CompositeElement} for child nodes based on the passed CSS selector (the selector should not contain an id).
         * @param {String} selector The CSS selector
         * @param {Boolean} [unique] True to create a unique Ext.Element for each element. Defaults to a shared flyweight object.
         * @return {Ext.CompositeElement} The composite element
         */
        select: function(selector, composite) {
            return Ext.dom.Element.select(selector, this.dom, composite);
        },

        /**
         * Selects child nodes based on the passed CSS selector (the selector should not contain an id).
         * @param {String} selector The CSS selector
         * @return {HTMLElement[]} An array of the matched nodes
         */
        query: function(selector) {
            return Ext.DomQuery.select(selector, this.dom);
        },

        /**
         * Selects a single child at any depth below this element based on the passed CSS selector (the selector should not contain an id).
         * @param {String} selector The CSS selector
         * @param {Boolean} [returnDom=false] True to return the DOM node instead of Ext.dom.Element
         * @return {HTMLElement/Ext.dom.Element} The child Ext.dom.Element (or DOM node if returnDom = true)
         */
        down: function(selector, returnDom) {
            var n = Ext.DomQuery.selectNode(selector, this.dom);
            return returnDom ? n : Ext.get(n);
        },

        /**
         * Selects a single *direct* child based on the passed CSS selector (the selector should not contain an id).
         * @param {String} selector The CSS selector
         * @param {Boolean} [returnDom=false] True to return the DOM node instead of Ext.dom.Element.
         * @return {HTMLElement/Ext.dom.Element} The child Ext.dom.Element (or DOM node if returnDom = true)
         */
        child: function(selector, returnDom) {
            var node,
                me = this,
                id;

            // Pull the ID from the DOM (Ext.id also ensures that there *is* an ID).
            // If this object is a Flyweight, it will not have an ID
            id = Ext.id(me.dom);
            // Escape "invalid" chars
            id = Ext.escapeId(id);
            node = Ext.DomQuery.selectNode('#' + id + " > " + selector, me.dom);
            return returnDom ? node : Ext.get(node);
        },

         /**
         * Gets the parent node for this element, optionally chaining up trying to match a selector
         * @param {String} [selector] Find a parent node that matches the passed simple selector
         * @param {Boolean} [returnDom=false] True to return a raw dom node instead of an Ext.dom.Element
         * @return {Ext.dom.Element/HTMLElement} The parent node or null
         */
        parent: function(selector, returnDom) {
            return this.matchNode('parentNode', 'parentNode', selector, returnDom);
        },

         /**
         * Gets the next sibling, skipping text nodes
         * @param {String} [selector] Find the next sibling that matches the passed simple selector
         * @param {Boolean} [returnDom=false] True to return a raw dom node instead of an Ext.dom.Element
         * @return {Ext.dom.Element/HTMLElement} The next sibling or null
         */
        next: function(selector, returnDom) {
            return this.matchNode('nextSibling', 'nextSibling', selector, returnDom);
        },

        /**
         * Gets the previous sibling, skipping text nodes
         * @param {String} [selector] Find the previous sibling that matches the passed simple selector
         * @param {Boolean} [returnDom=false] True to return a raw dom node instead of an Ext.dom.Element
         * @return {Ext.dom.Element/HTMLElement} The previous sibling or null
         */
        prev: function(selector, returnDom) {
            return this.matchNode('previousSibling', 'previousSibling', selector, returnDom);
        },

        /**
         * Gets the first child, skipping text nodes
         * @param {String} [selector] Find the next sibling that matches the passed simple selector
         * @param {Boolean} [returnDom=false] True to return a raw dom node instead of an Ext.dom.Element
         * @return {Ext.dom.Element/HTMLElement} The first child or null
         */
        first: function(selector, returnDom) {
            return this.matchNode('nextSibling', 'firstChild', selector, returnDom);
        },

        /**
         * Gets the last child, skipping text nodes
         * @param {String} [selector] Find the previous sibling that matches the passed simple selector
         * @param {Boolean} [returnDom=false] True to return a raw dom node instead of an Ext.dom.Element
         * @return {Ext.dom.Element/HTMLElement} The last child or null
         */
        last: function(selector, returnDom) {
            return this.matchNode('previousSibling', 'lastChild', selector, returnDom);
        },

        matchNode: function(dir, start, selector, returnDom) {
            if (!this.dom) {
                return null;
            }

            var n = this.dom[start];
            while (n) {
                if (n.nodeType == 1 && (!selector || Ext.DomQuery.is(n, selector))) {
                    return !returnDom ? Ext.get(n) : n;
                }
                n = n[dir];
            }
            return null;
        },

        isAncestor: function(element) {
            return this.self.isAncestor.call(this.self, this.dom, element);
        }
    });