Nuxt/packages/webpack/src/presets/vue.ts

import { resolve } from 'pathe'
import VueLoaderPlugin from 'vue-loader/dist/pluginWebpack5.js'
import VueSSRClientPlugin from '../plugins/vue/client'
import VueSSRServerPlugin from '../plugins/vue/server'
import type { WebpackConfigContext } from '../utils/config'

import { webpack } from '#builder'

export function vue (ctx: WebpackConfigContext) {
  // @ts-expect-error de-default vue-loader
  ctx.config.plugins!.push(new (VueLoaderPlugin.default || VueLoaderPlugin)())

  ctx.config.module!.rules!.push({
    test: /\.vue$/i,
    loader: 'vue-loader',
    options: ctx.userConfig.loaders.vue,
  })

  if (ctx.isClient) {
    ctx.config.plugins!.push(new VueSSRClientPlugin({
      filename: resolve(ctx.options.buildDir, 'dist/server', `${ctx.name}.manifest.json`),
      nuxt: ctx.nuxt,
    }))
  } else {
    ctx.config.plugins!.push(new VueSSRServerPlugin({
      filename: `${ctx.name}.manifest.json`,
    }))
  }

  // Feature flags
  // https://github.com/vuejs/vue-next/tree/master/packages/vue#bundler-build-feature-flags
  // TODO: Provide options to toggle
  ctx.config.plugins!.push(new webpack.DefinePlugin({
    '__VUE_OPTIONS_API__': 'true',
    '__VUE_PROD_DEVTOOLS__': 'false',
    '__VUE_PROD_HYDRATION_MISMATCH_DETAILS__': ctx.nuxt.options.debug && ctx.nuxt.options.debug.hydration,
  }))
}