babelHelpers 默認就是 bundled ,打成umi格式包時,需要配合 @rollup/plugin-node-resolve 和 rollup-plugin-commonjs 這倆插件一起使用。參考:import babel from '@rollup/plugin-babel';import resolve from '@rollup/plugin-node-resolve';import commonjs from 'rollup-plugin-commonjs';export default { input: 'index.js', output: { file: 'dist/index.js', format: 'umd', name: 'test', strict: false }, plugins: [ commonjs(), resolve(), babel({ babelrc: false, babelHelpers: 'bundled', exclude: 'node_modules/**', presets: [ [ '@babel/preset-env', { targets: { browsers: '> 1%, ie >= 11' }, useBuiltIns: 'usage', corejs: 3 } ] ] }) ]};