title: Node modules issue: Only one default export allowed per module
body: <p>This a issue we faced while doing an <code>npm install</code> on server which loaded new set of version for node_modules. </p>
  
  <p>We have a module which looks like</p>
  
  <pre><code>export default class DemoComponent extend React.Component {
    render() {
      return(
        &lt;h1&gt;Hello&lt;/h1&gt;
      );
    }
  }
  
  export default connect(
    mapStateToProps,
    { ... }
  )(DemoComponent);
  </code></pre>
  
  <p>It used to work fine before we  did <code>npm install</code> which loaded a new version of development dependencies. </p>
  
  <p>ERROR LOG:</p>
  
  <blockquote>
    <p>Only one default export allowed per module.
        at File.buildCodeFrameError (/home/workspace/node_modules/babel-core/lib/transformation/file/index.js:431:15)
        at NodePath.buildCodeFrameError (/home/workspace/node_modules/babel-traverse/lib/path/index.js:140:26)
        at PluginPass.exit (/home/workspace/node_modules/babel-plugin-transform-es2015-modules-commonjs/lib/index.js:253:29)
        at newFn (/home/workspace/node_modules/babel-traverse/lib/visitors.js:276:21)
        at NodePath._call (/home/workspace/node_modules/babel-traverse/lib/path/context.js:76:18)
        at NodePath.call (/home/workspace/node_modules/babel-traverse/lib/path/context.js:48:17)
        at NodePath.visit (/home/workspace/node_modules/babel-traverse/lib/path/context.js:117:8)
        at TraversalContext.visitQueue (/home/workspace/node_modules/babel-traverse/lib/context.js:150:16)
        at TraversalContext.visitSingle (/home/workspace/node_modules/babel-traverse/lib/context.js:108:19)
        at TraversalContext.visit (/home/workspace/node_modules/babel-traverse/lib/context.js:192:19)
        at Function.traverse.node (/home/workspace/node_modules/babel-traverse/lib/index.js:161:17)</p>
  </blockquote>