zoro-cli/lib/plugins/config-webpack/template/script/config/babel.js

https://github.com/vuejs/vue-cli

const { resolveCwd } = require('zoro-cli-util/resolve')

module.exports = ({ api, options, envUtil }) => {
  const isProd = envUtil.isProduction()
  const useThreads = isProd && options.parallel

  api.chainWebpack(webpackConfig => {
    const versions = {}
    /* eslint-disable import/no-unresolved */
    if (resolveCwd('babel-preset-zoro-vue')) {
      versions[
        'babel-preset-zoro-vue'
      ] = require('babel-preset-zoro-vue/package.json').version
    } else if (resolveCwd('babel-preset-zoro-react')) {
      versions[
        'babel-preset-zoro-react'
      ] = require('babel-preset-zoro-react/package.json').version
    }
    /* eslint-enable import/no-unresolved */

    const jsRule = webpackConfig.module
      .rule('js')
      .test(/\.(j|t)sx?$/)
      .exclude.add(filepath => {
        // always transpile js in vue files
        // but do not transpile those in node_modules, because they maybe compiled already
        // if you need to compile vue in node_modules, please use transpileDependencies
        if (
          /\.vue\.(j|t)sx?$/.test(filepath) &&
          !/node_modules/.test(filepath)
        ) {
          return false
        }
        // FIXME:
        // exclude dynamic entries from cli-service
        // if (filepath.startsWith(cliServicePath)) {
        //   return true
        // }
        // check if this is something the user explicitly wants to transpile
        if (options.transpileDependencies.some(dep => filepath.match(dep))) {
          return false
        }
        // Don't transpile node_modules
        return /node_modules/.test(filepath)
      })
      .end()
      .use('cache-loader')
      .loader('cache-loader')
      .options(
        api.genCacheConfig(
          'babel-loader',
          {
            '@babel/core': require('@babel/core/package.json').version,
              'babel-loader': require('babel-loader/package.json').version,
            ...versions,
          },
          [
            'src/.babelrc.js',
            'src/babel.config.js',
            '.babelrc.js',
            'babel.config.js',
          ],
        ),
      )
      .end()

    if (useThreads) {
      jsRule.use('thread-loader').loader('thread-loader')
    }

    jsRule.use('babel-loader').loader('babel-loader')
  })
}