通过Babel来判断是否安装了某个依赖包(非原创)

/**
 * 判断是否安装了某个包
 * @param {string} pkg 包名
 */
const hasPkg = pkg => {
  const pkgPath = path.join(process.cwd(), `package.json`);
  const pkgJson = fs.existsSync(pkgPath) ? fse.readJsonSync(pkgPath) : {};
  const { dependencies = {}, devDependencies = {} } = pkgJson;
  return dependencies[pkg] || devDependencies[pkg];
}

/**
 * 通过 npm 安装包
 * @param {string} pkg 包名
 */
const installPkg = pkg => {
  console.log(`开始安装 ${pkg}`);
  const npm = shell.which('npm');
  if (!npm) {
    console.log('请先安装 npm');
    return;
  }
  const { code } = shell.exec(`${npm.stdout} install ${pkg} -S`);
  if (code) {
    console.log(`安装 ${pkg} 失败，请手动安装`);
  }
};

if (!hasPkg(TARGET_PKG_NAME)) {
  installPkg(TARGET_PKG_NAME);
}