Find a path from one node to another

DOMTreePath

var getPath = function (start, end) {
    
    var getParents = function (el) {
    
        var parents = [el];
            el = el.parentElement;

            while (el.parentElement) {
                parents.push(el = el.parentElement);
            }
            return parents;
        },
        
        intersection = function (a, b) {
        
            var shorter = (a.length < b.length) ? a : b,
                longer = (shorter === a) ? b : a,
                shorterLen = shorter.length,
                intersection = [],
                i;

            for (i = 0; i < shorterLen; i++) {
                if (longer.indexOf(shorter[i]) >= 0 ) {
                    intersection.push(shorter[i]);
                }
            }
            
            return intersection;
        },
        
        getSelectorPath = function (ancestry) {
            var i, len, _ref, nodeName, selPath = [];

            for (i = 0, len = ancestry.length; i < len; i++) {
                _ref = ancestry[i];
                nodeName = _ref.nodeName;
                selPath.push(nodeName.toLowerCase() + (_ref.id ? '#' + _ref.id : '') + (_ref.className ? '.' + _ref.className.split(' ').join('.') : ''));
            }

            return selPath;
        },

        parentsA = getParents(start),
        parentsB = getParents(end),
        commonParent = intersection(parentsA, parentsB)[0],
        pathA, pathB;

    parentsA = parentsA.slice(0, parentsA.indexOf(commonParent) + 1);
    parentsB = parentsB.slice(0, parentsB.indexOf(commonParent));
    pathA = getSelectorPath(parentsA);
    pathB = getSelectorPath(parentsB)

    return {
        length: pathA.length + pathB.length,
        path: pathA.join(' < ') + pathB.join(' > ')
    }
};