js webpack extracted public code tree-shaking difference js

Resolve

Js block first extracts the common program is arranged for multi-inlet

Configuration is as follows:

js custom code block

name: Specifies the name of the file pack out

chunks: Look

minSize: 1 package file size

minChunks: indicates how many times the module is referenced to the common module

priority: 1 indicating priority when there are a plurality of common modules when 

 output: {
        path: path.resolve(__dirname, 'dist'),
        filename: '[name][hash:3].bundle.js',
        //将公共 js单独提取到该输出文件 其他模块将不再包含这里面的内容
        chunkFilename: '[name][hash:3].js'
    },

optimization: {
        splitChunks: {
            cacheGroups: {
                common: {
                    chunks: 'all',
                    minSize: 1,
                    // minChunks: 2,
                    name: 'common',
                    priority: 2,
                    test: /\.js$/
                }
            }
        },
     
    },

 

For when referring to third-party software libraries

Configuration is as follows

Regular test pack which indicates a third-party library

 

Difference between the two:

 

C shows the first file tree-shaking referenced B in terms of B file for a particular document references a file A is a longitudinal reference js

As scope chain itself as webpack js-tree-shaing does not have scope filtering. FIG. A method of file references a

Shaking does not have the function mode npm run dev

Under npm run prod a packing mode a, c, d method does not have the functionality to be removed scope filters c, d depth tree-shaking

Depth tree-shaking not only relates to a package outside the scope of the code