apps/meteor/packages/flow-router/lib/router.js
Router.prototype.url = function () {
// We need to remove the leading base path, or "/", as it will be inserted
// automatically by `Meteor.absoluteUrl` as documented in:
// http://docs.meteor.com/#/full/meteor_absoluteurl
var completePath = this.path.apply(this, arguments);
var basePath = this._basePath || '/';
var pathWithoutBase = completePath.replace(new RegExp('^' + basePath), '');
return Meteor.absoluteUrl(pathWithoutBase);
};