使用babel和webpack构建捆绑包时生成的重复帮助程序功能

编程问答 2022-07-27

问题描述

我正在尝试使用webpack和babel构建尽可能小的捆绑包。

我知道，为了跳过extends，classCallCheck等的重复，我应该使用 @ babel / plugin-transform-runtime ，它可以按预期工作。

不幸的是，仍然有一些函数在使用它们的模块的开头定义了很多次。其中一些是：

function ownKeys(object,enumerableOnly) { var keys = Object.keys(object); if (Object.getownPropertySymbols) { var symbols = Object.getownPropertySymbols(object); if (enumerableOnly) symbols = symbols.filter(function (sym) { return Object.getownPropertyDescriptor(object,sym).enumerable; }); keys.push.apply(keys,symbols); } return keys; }

function _arrayLiketoArray(arr,len) { if (len == null || len > arr.length) len = arr.length; for (var i = 0,arr2 = new Array(len); i < len; i++) { arr2[i] = arr[i]; } return arr2; }

function _createForOfIteratorHelper(o,allowArrayLike) { var it; if (typeof Symbol === "undefined" || o[Symbol.iterator] == null) { if (Array.isArray(o) || (it = _unsupportedIterabletoArray(o)) || allowArrayLike && o && typeof o.length === "number") { if (it) o = it; var i = 0; var F = function F() {}; return { s: F,n: function n() { if (i >= o.length) return { done: true }; return { done: false,value: o[i++] }; },e: function e(_e) { throw _e; },f: F }; } throw new TypeError("Invalid attempt to iterate non-iterable instance.\nIn order to be iterable,non-array objects must have a [Symbol.iterator]() method."); } var normalCompletion = true,didErr = false,err; return { s: function s() { it = o[Symbol.iterator](); },n: function n() { var step = it.next(); normalCompletion = step.done; return step; },e: function e(_e2) { didErr = true; err = _e2; },f: function f() { try { if (!normalCompletion && it.return != null) it.return(); } finally { if (didErr) throw err; } } }; }

依此类推...

我的配置文件是：

babel.config.js 

module.exports = function(api) {
  api.cache(false);
  const presets = [
    ["@babel/preset-typescript"],[
      "@babel/preset-env",{
        "targets": {
          "edge": "14","chrome": "61","safari": "11.1","ie": "11","ios": "8"
        }
      }
    ]
  ];
  const plugins = [
    ["@babel/plugin-proposal-class-properties",{ "loose": true }],["@babel/plugin-transform-runtime"]]
  return {
    presets,plugins,sourceType: "unambiguous"
  };
};

webpack：

      config.entry = [
        "core-js/stable/array/includes","core-js/stable/array/find","core-js/stable/array/from","core-js/stable/promise","core-js/stable/map","core-js/stable/set","core-js/stable/symbol/async-iterator","regenerator-runtime/runtime","intersection-observer",bundleEntry];

我在配置Babel上玩了很多，但没有成功。任何帮助将不胜感激。

解决方法

原来，github中有最近的问题：
https://github.com/preconstruct/preconstruct/issues/297 https://github.com/preconstruct/preconstruct/issues/318

TL; DR;

@ babel / plugin-transform-runtime 的

version 参数应添加到babel配置文件中：

 ["@babel/plugin-transform-runtime",{"version": "7.11.5"}]
babel-pluginbabeljsjavascriptwebpackwebpackwebpack