UglifyJS Webpack Plugin
Note that webpack contains the same plugin under
webpack.optimize.UglifyJsPlugin. This is a standalone version for those that want to control the version of UglifyJS. The documentation is valid apart from the installation instructions in that case.
yarn add uglifyjs-webpack-plugin --dev
npm install uglifyjs-webpack-plugin --save-dev
Important! The plugin has a peer dependency to uglify-js, so in order to use the plugin, also uglify-js has to be installed. The currently (2017/1/25) available uglify-js npm packages; however, do not support minification of ES6 code. In order to support ES6, an ES6-capable, a.k.a. harmony, version of UglifyJS has to be provided.
If your minification target is ES6:
yarn add git://github.com/mishoo/UglifyJS2#harmony-v2.8.22 --dev
If your minification target is ES5:
yarn add uglify-js --dev
const UglifyJSPlugin = ;moduleexports =entry: ...output: ...module: ...plugins:;
This plugin supports UglifyJS features as discussed below:
|compress||boolean, object||true||See UglifyJS documentation.|
|mangle||boolean, object||true||See below.|
|output||An object providing options for UglifyJS OutputStream||Lower level access to UglifyJS output.|
|comments||boolean, RegExp, function(astNode, comment) -> boolean||Defaults to preserving comments containing
||Comment related configuration.|
|extractComments||boolean, RegExp, function (astNode, comment) -> boolean, object||false||Whether comments shall be extracted to a separate file, (see details, since webpack 2.3.0)|
|sourceMap||boolean||false||Use SourceMaps to map error message locations to modules. This slows down the compilation. Important!
||Test to match files against.|
|include||RegExp, Array||Test only
|exclude||RegExp, Array||Files to
|warningsFilter||function(source) -> boolean||Allow to filter uglify warnings (since webpack 2.3.0)|
mangle (boolean|object) - Passing
true or an object enables and provides options for UglifyJS name mangling. See UglifyJS documentation for mangle options. Example configuration, this will not mangle properties (see below):
mangle:// Skip mangling theseexcept: '$super' '$' 'exports' 'require'
mangle.props (boolean|object) - Passing
true or an object enables and provides options for UglifyJS property mangling - see UglifyJS documentation for mangleProperties options.
Note: the UglifyJS docs warn that you will probably break your source if you use property mangling, so if you aren’t sure why you’d need this feature, you most likely shouldn’t be using it! This is not enabled by default.
Example configuration, this will mangle both names and properties:
extractComments option can be
true: All comments that normally would be preserved by the
commentsoption will be moved to a separate file. If the original file is named
foo.js, then the comments will be stored to
- regular expression (given as
string) or a
function (astNode, comment) -> boolean: All comments that match the given expression (resp. are evaluated to
trueby the function) will be extracted to the separate file. The
commentsoption specifies whether the comment will be preserved, i.e. it is possible to preserve some comments (e.g. annotations) while extracting others or even preserving comments that have been extracted.
objectconsisting of the following keys, all optional:
condition: regular expression or function (see previous point)
filename: The file where the extracted comments will be stored. Can be either a
function (string) -> stringwhich will be given the original filename. Default is to append the suffix
.LICENSEto the original filename.
banner: The banner text that points to the extracted file and will be added on top of the original file. will be added to the original file. Can be
false(no banner), a
string, or a
function (string) -> stringthat will be called with the filename where extracted comments have been stored. Will be wrapped into comment. Default:
/*! For license information please see foo.js.LICENSE */