Function buildFallbackWorker

build-fallback-worker.js:57–144

({ id, fallbacks, basedir, destdir, minify, pageExtensions })

}

const buildFallbackWorker = ({ id, fallbacks, basedir, destdir, minify, pageExtensions }) => {
  const envs = getFallbackEnvs({ fallbacks, basedir, id, pageExtensions })
  if (!envs) return

  const name = `fallback-${id}.js`
  const fallbackJs = path.join(__dirname, `fallback.js`)

  webpack({
    mode: 'none',
    target: 'webworker',
    entry: {
      main: fallbackJs
    },
    resolve: {
      extensions: ['.js'],
      fallback: {
        module: false,
        dgram: false,
        dns: false,
        path: false,
        fs: false,
        os: false,
        crypto: false,
        stream: false,
        http2: false,
        net: false,
        tls: false,
        zlib: false,
        child_process: false
      }
    },
    module: {
      rules: [
        {
          test: /\.js$/i,
          use: [
            {
              loader: 'babel-loader',
              options: {
                presets: [
                  [
                    'next/babel',
                    {
                      'transform-runtime': {
                        corejs: false,
                        helpers: true,
                        regenerator: false,
                        useESModules: true
                      },
                      'preset-env': {
                        modules: false,
                        targets: 'chrome >= 56'
                      }
                    }
                  ]
                ]
              }
            }