【规范】统一项目中包管理器的使用

npm/6.14.5 node/v14.17.1 win32 x64
yarn/1.22.10 npm/? node/v14.17.1 win32 x64

const allowPM = 'yarn'
const userAgent = process.env.npm_config_user_agent || ''
if (userAgent !== '') {
  const pmName = userAgent.substring(0, userAgent.indexOf('/'))
  if (pmName !== allowPM) {
    console.warn(
      `\u001b[33m This repository requires using ${allowPM} as the package manager for scripts to work properly.\u001b[39m\n`
    )
    process.exit(1)
  }
}

{
  "scripts": {
    "preinstall": "node ./preinstall.js"
  }
}

C:\Users\OSpoon\AppData\Roaming\nvm\v14.17.1\node_modules\npm\bin\npm-cli.js
C:\Users\OSpoon\AppData\Roaming\npm\node_modules\yarn\bin\yarn.js

const allowPM = 'yarn'
const execpath = process.env.npm_execpath || ''
if (!new RegExp(`${allowPM}`).test(execpath)) {
  console.warn(
    `\u001b[33m This repository requires using ${allowPM} as the package manager for scripts to work properly.\u001b[39m\n`
  )
  process.exit(1)
}

{
  "scripts": {
    "preinstall": "node ./preinstall.js"
  }
}

{
  "scripts": {
    "preinstall": "npx only-allow yarn"
  }
}