Webpack5打包web3.js1.4.0出现Cannot read property 'custom' of undefined错误如何解决

API 探路者

2026-10-11

修复方案

错误根因

Webpack 5 默认移除了Node.js核心模块的内置polyfill，你使用的node-polyfill-webpack-plugin对util模块的polyfill覆盖不完整，导致assert库调用require('util/').inspect时返回undefined，读取inspect.custom属性时报错。

修复步骤

第一步：手动安装完整的util polyfill

npm install util --save

第二步：修改webpack配置，新增resolve配置明确指向util polyfill，修改后的完整配置如下：

// webpack configuration file
const NodePolyfillPlugin = require("node-polyfill-webpack-plugin");
const path = require('path');

module.exports = {
    mode: 'development',
    output: {
        path: path.resolve(__dirname, 'dist/dev'),
        filename: '[name].bundle.js',
    },
    entry: {
        index: './src/index.js'
    },
    // 新增以下resolve配置
    resolve: {
        alias: {
            'util': require.resolve('util/')
        },
        fallback: {
            "util": require.resolve("util/")
        }
    },
    module: {
        rules: [
            {
                test: /\.css$/,
                use: ['css-loader'],
            }
        ]
    },
    plugins: [
        new NodePolyfillPlugin()
    ]
}