Route.js

import invariant from 'invariant';
import React from 'react';
import BaseRoute from 'react-router/lib/Route';

import LoadingIndicator from './LoadingIndicator';

// This is not a component.
/* eslint-disable react/prop-types */
function render({ props, element }) {
  if (!props) {
    return <LoadingIndicator />;
  }

  if (this.renderFetched) {
    return this.renderFetched(props);
  }

  return React.cloneElement(element, props);
}
/* eslint-enable react/prop-types */

function createRoute(element) {
  const route = BaseRoute.createRouteFromReactElement(element);

  if (!route.render && (route.queries || route.getQueries)) {
    route.render = render;
  }

  return route;
}

function Route() {
  invariant(false, '`<Route>` should not be rendered.');
}

Route.createRouteFromReactElement = createRoute;

export default Route;

function createIndexRoute(element, parentRoute) {
  invariant(parentRoute, 'An `<IndexRoute>` must have a parent.');

  /* eslint-disable no-param-reassign */
  parentRoute.indexRoute = createRoute(element);
  /* eslint-enable no-param-reassign */
}

function IndexRoute() {
  invariant(false, '`<IndexRoute>` should not be rendered.');
}

IndexRoute.createRouteFromReactElement = createIndexRoute;

export { IndexRoute };