Merge webpack plugin configuration / DefinePlugin

Current Behavior

If you add a DefinePlugin section to your webpack.haul.js / config plugins, it will override the default DefinePlugin stuff set up for you by makeReactNativeConfig. For example, you could have a webpack.haul.js like:

module.exports = ({ platform }) => ({
  entry: `./index.js`,
  plugins: [
    new webpack.DefinePlugin({
      'API_HOST': JSON.stringify(process.env.API_HOST),
    }),
  ]
});

If you try to run your app, you’ll get mysterious errors such as undefined variable __DEV__, but after looking into it the problem is that the plugins are overridden.

Expected Behavior

I think there are a few options here.

1. haul should be able to intelligently merge plugins
2. haul should provide documentation / a clear path for merging of plugins
3. Just for my specific case, haul should provide the ability to forward environment variables or other fine grained configuration.

Haul Configuration (webpack.haul.js)

Sufficient to reproduce:

module.exports = ({ platform }) => ({
  entry: `./index.js`,
  plugins: [],
});

Your Environment

software	version
Haul	v1.0.0-beta.13
react-native	0.53.0
node	9.5
npm or yarn	1.3.2

[baygeldin]

That’s a good point. Although looking at webpack-merge sources I’m not sure if it can merge plugins configuration, but it can swap plugins though. Anyway, babel-plugin-transform-inline-environment-variables works perfectly for my usecase, so it’s okay. Thanks for your help. Keep it up, Haul is a great tool 😃

[satya164]

@baygeldin with the new config format you can use something like webpack-merge to do the merging. I think it’s better that we don’t try to solve this problem because there are other tools which try to solve it already.