webpack5和webpack4打包结果对比

// index.js
console.log("test");

// webpack4
(function (modules) { // webpackBootstrap
    // The module cache
    var installedModules = {};

    // The require function
    function __webpack_require__(moduleId) {
        // Check if module is in cache
        if (installedModules[moduleId]) {
            return installedModules[moduleId].exports;
        }
        // Create a new module (and put it into the cache)
        var module = installedModules[moduleId] = {
            i: moduleId,
            l: false,
            exports: {}
        };
        // 调用执行当前的函数
        modules[moduleId].call(module.exports, module, module.exports, __webpack_require__);
        return module.exports;
    }
    // Load entry module and return exports
    return __webpack_require__("./src/index.js");
})
({
    "./src/index.js": (function (module, exports) {
        console.log("test");
    })
});

// webpack5
(() => {
  console.log("test");
})();

// importInfo.js
export const data = "from import data";

// index.js
import {data} from "./importInfo";
console.log("test");
console.log(data);

// webpack4 还是那个熟悉的闭包那个自执行函数
(function (modules) { // webpackBootstrap
    // The module cache
    var installedModules = {};
    // The require function
    function __webpack_require__(moduleId) {
        // Check if module is in cache
        if (installedModules[moduleId]) {
            return installedModules[moduleId].exports;
        }
        // Create a new module (and put it into the cache)
        var module = installedModules[moduleId] = {
            i: moduleId,
            l: false,
            exports: {}
        };
        // 调用执行当前的函数
        modules[moduleId].call(module.exports, module, module.exports, __webpack_require__);
        // Flag the module as loaded
        module.l = true;
        // Return the exports of the module
        return module.exports;
    }

    // Load entry module and return exports
    return __webpack_require__("./src/index.js");
})
({
    "./src/importInfo.js": (function (module, __webpack_exports__, __webpack_require__) {
        Object.defineProperty(__webpack_exports__,
            "data", {
                get: function () {
                    return data;
                }
            });
        const data = "from import data";
    }),
    "./src/index.js": (function (module, __webpack_exports__, __webpack_require__) {
        var _importInfo__WEBPACK_IMPORTED_MODULE_0__ = __webpack_require__("./src/importInfo.js");
        console.log("test");
        console.log(_importInfo__WEBPACK_IMPORTED_MODULE_0__["data"]);
    })

});

// webpack5
// 将原本传入的key value 文件对象直接放到了函数里面
(() => {
  var __webpack_modules__ = ({
    "./src/importInfo.js": ((__unused_webpack_module, __webpack_exports__, __webpack_require__) => {
      // 这里的兼容写法有所变化
      const definition = {
        "data": () => data
      };
      for (var key in definition) {
        Object.defineProperty(exports, key, {
          get: definition[key]
        });
      }
      const data = "from import data";
    }),
    "./src/index.js": ((__unused_webpack_module, __webpack_exports__, __webpack_require__) => {
      var _importInfo__WEBPACK_IMPORTED_MODULE_0__ = __webpack_require__("./src/importInfo.js");
      console.log("test");
      console.log(_importInfo__WEBPACK_IMPORTED_MODULE_0__.data);
    })
  });
  var __webpack_module_cache__ = {};

  // The require function
  function __webpack_require__(moduleId) {
    // Check if module is in cache
    if (__webpack_module_cache__[moduleId]) {
      return __webpack_module_cache__[moduleId].exports;
    }
    // Create a new module (and put it into the cache)
    var module = __webpack_module_cache__[moduleId] = {
      //去除了不需要情况下的i 和 l
      // no module.id needed
      // no module.loaded needed
      exports: {}
    };
    // Execute the module function
    __webpack_modules__[moduleId](module, module.exports, __webpack_require__);

    // Return the exports of the module
    return module.exports;
  }
  __webpack_require__("./src/index.js");
  // This entry module used 'exports' so it can't be inlined
})();