esm-webpack-plugin issue #15 playground

When using the @purtuga/esm-webpack-plugin together with the webpack-dev-server while having hot: true the ESM plugin generates an invalid module.

The desired behavior

Will launch a webpage with two links that render basic components. They are defined in the webpack-dev-server hosted http://localhost/index.js. One of them is code-split.

git clone https://github.com/riovir/esm-webpack-plugin-i15-reprod.git
cd esm-webpack-plugin-i15-reprod
npm install
npm start

The problem

When the HMR gets turned on it will generate an extra module which confused the esm-webpack-plugin causing extra default exports to be added to the result, making it invalid.

When trying to npm start the app with the hot: true, the following error will be shown in the console

index.js:1394 Uncaught (in promise) SyntaxError: Identifier '.default' has already been declared

Opening http://localhost/index.js will reveal it to end like this:

// ...

export default examplePackage;
export { examplePackage };

/** caused by the dev-server generated HMR module */
export default examplePackage; 
export { examplePackage };

const _examplePackage$getRoutes = examplePackage['getRoutes'];

export {
    _examplePackage$getRoutes as getRoutes
}