validate-lock-file.js

const fs = require('fs')
const path = require('path')
const url = require('url')
const lockfile = require('@yarnpkg/lockfile')

const errorsSymbol = Symbol('errors')

const packageRegistryShouldBeGlobal = entry => {
  const { resolved, [errorsSymbol]: errors } = entry
  const link = url.parse(resolved)
  if (link.host !== 'registry.yarnpkg.com') {
    errors.push(
      `package registry should be 'registry.yarnpkg.com' but locked to ${link.host}`
    )
  }
  return entry
}

const mapYarnLockEntries = cb => {
  const contents = fs.readFileSync(path.resolve('yarn.lock'), 'utf-8')
  const yarnLock = lockfile.parse(contents)
  return Object.keys(yarnLock.object).map(key =>
    cb({
      ...yarnLock.object[key],
      name: key,
      [errorsSymbol]: []
    })
  )
}

try {
  const errors = mapYarnLockEntries(packageRegistryShouldBeGlobal).reduce(
    (output, entry) => {
      entry[errorsSymbol].map(error => output.push(`[${entry.name}]: ${error}`))
      return output
    },
    []
  )
  if (errors.length) {
    // eslint-disable-next-line
    errors.map(error => console.error(error))
    process.exit(1)
  }
} catch (error) {
  // eslint-disable-next-line
  console.error(error.message)
  process.exit(1)
}