j-gallery/example/node_modules/react-hot-loader/RootInstanceProvider.js

a picture layout library

'use strict';

var getRootInstancesFromReactMount = require('./getRootInstancesFromReactMount');

var injectedProvider = null,
    didWarn = false;

function warnOnce() {
  if (!didWarn) {
    console.warn(
      'It appears that React Hot Loader isn\'t configured correctly. ' +
      'If you\'re using NPM, make sure your dependencies don\'t drag duplicate React distributions into their node_modules and that require("react") corresponds to the React instance you render your app with.',
      'If you\'re using a precompiled version of React, see https://github.com/gaearon/react-hot-loader/tree/master/docs#usage-with-external-react for integration instructions.'
    );
  }

  didWarn = true;
}

var RootInstanceProvider = {
  injection: {
    injectProvider: function (provider) {
      injectedProvider = provider;
    }
  },

  getRootInstances: function (ReactMount) {
    if (injectedProvider) {
      return injectedProvider.getRootInstances();
    }

    var instances = ReactMount && getRootInstancesFromReactMount(ReactMount) || [];
    if (!Object.keys(instances).length) {
      warnOnce();
    }

    return instances;
  }
};

module.exports = RootInstanceProvider;