开门见山

在使用webpack构建vue中遇到了一些插件问题，插件是copy-webpack-plugin ，报错信息如下

ERROR in Cannot read property 'map' of undefined

一开始我以为是html-webpack-plugin的问题，后来才发现是copy-webpack-plugin的问题

错误代码

const CopyWebpackPlugin = require('copy-webpack-plugin');

 new CopyWebpackPlugin([  { from: 'from/file.txt' },

            // equivalent
            'from/file.txt',

            // {output}/to/file.txt
            { from: 'from/file.txt', to: 'to/file.txt' },

            // {output}/to/directory/file.txt
            { from: 'from/file.txt', to: 'to/directory' },
            
            ])
            
这种写法是webpack中文网上面的写法，实际上这种写法不对

正确写法

const CopyWebpackPlugin = require("copy-webpack-plugin");

     new CopyWebpackPlugin({
            patterns: [{
                    from: path.join(__dirname, '../public/favicon.ico'),
                    to: '.'
                },
                {
                    from: path.join(__dirname, '../public/cloud.jpeg'),
                    to: '.'
                }

            ],
            options: {
                concurrency: 100,
            },
        })
这才是正确写法，这是npm上面的写法，中文网害死人，白耽误我时间

谢谢观看，如有不足，敬请指教