React native package `main` field related error.

Hei,

I’m trying to plug supertruct to a react-native app, but i’m getting this error

error: Error: While trying to resolve module `superstruct` from file `validation.js`, the package `node_modules/superstruct/package.json` was successfully found. 
However, this package itself specifies a `main` module field that could not be resolved (`node_modules/superstruct/index.cjs`. Indeed, none of these files exist:

[leolangen]

We have a different version of metro-config in our project, using RN version 0.61.2. The following worked for me

...
const defaultSourceExts = require('metro-config/src/defaults/defaults').sourceExts 

module.exports = {
  ...
  resolver: {
    sourceExts: [...defaultSourceExts, 'cjs'],
    ...
  }
}

[isnifer]

But this config for metro bundler helped me:

// https://github.com/ioveracker/demo-react-native-emotion/blob/master/metro.config.js

const { getDefaultConfig } = require('metro-config');

module.exports = (async () => {
    const {
        resolver: { sourceExts },
    } = await getDefaultConfig();
    return {
        resolver: {
            // Add cjs extension so stylis will load.
            sourceExts: [...sourceExts, 'cjs'],
        },
        transformer: {
            getTransformOptions: async () => ({
                transform: {
                    experimentalImportSupport: false,
                    inlineRequires: false,
                },
            }),
        },
    };
})();