getNextConfig.js

'use strict'

const { resolve } = require('path')

const { defaultFailBuild } = require('./defaultFailBuild')
const moize = require('moize')

// Load next.config.js
const getNextConfig = async function (params = {}) {
  const { failBuild = defaultFailBuild, publishPath = '.' } = params

  // We cannot load `next` at the top-level because we validate whether the
  // site is using `next` inside `onPreBuild`.
  const { PHASE_PRODUCTION_BUILD } = require('next/constants')
  const loadConfig = require('next/dist/next-server/server/config').default

  try {
    return await loadConfig(PHASE_PRODUCTION_BUILD, resolve(publishPath))
  } catch (error) {
    return failBuild('Error loading your next.config.js.', { error })
  }
}

const moizedGetNextConfig = moize(getNextConfig, { maxSize: 1e3, isPromise: true, isDeepEqual: true })

module.exports = moizedGetNextConfig