feat: support minify function option

README.md

@@ -50,6 +50,7 @@ module.exports = {
 |**`cacheKeys`**|`{Function(defaultCacheKeys, file) -> {Object}}`|`defaultCacheKeys => defaultCacheKeys`|Allows you to override default cache keys|
 |**`parallel`**|`{Boolean\|Number}`|`false`|Use multi-process parallel running to improve the build speed|
 |**`sourceMap`**|`{Boolean}`|`false`|Use source maps to map error message locations to modules (This slows down the compilation) ⚠️ **`cheap-source-map` options don't work with this plugin**|
+|**`minify`**|`{Function}`|`undefined`|Allows you to override default minify function|
 |**`uglifyOptions`**|`{Object}`|[`{...defaults}`](https://github.com/webpack-contrib/uglifyjs-webpack-plugin/tree/master#uglifyoptions)|`uglify` [Options](https://github.com/mishoo/UglifyJS2/tree/harmony#minify-options)|
 |**`extractComments`**|`{Boolean\|RegExp\|Function<(node, comment) -> {Boolean\|Object}>}`|`false`|Whether comments shall be extracted to a separate file, (see [details](https://github.com/webpack/webpack/commit/71933e979e51c533b432658d5e37917f9e71595a) (`webpack >= 2.3.0`)|
 |**`warningsFilter`**|`{Function(source) -> {Boolean}}`|`() => true`|Allow to filter uglify warnings|
@@ -89,6 +90,8 @@ module.exports = {
 
 ### `cache`
 
+If you use custom `minify` function please read `minify` option section for cache invalidation correctly.
+
 #### `{Boolean}`
 
 **webpack.config.js**
@@ -178,6 +181,8 @@ Number of concurrent runs.
 
 ### `sourceMap`
 
+If you use custom `minify` function please read `minify` option section for handle source maps correctly.
+
 **webpack.config.js**
 ```js
 [
@@ -189,6 +194,102 @@ Number of concurrent runs.
 
 > ⚠️ **`cheap-source-map` options don't work with this plugin**
 
+### `minify`
+
+**webpack.config.js**
+```js
+[
+  new UglifyJsPlugin({
+     minify(file, sourceMap) {
+       const extractedComments = [];
+
+       // Custom logic for extract comments
+
+       const { error, map, code, warnings } = minify(
+         file,
+         { /* Your options for minification */ },
+       );
+
+       return { error, map, code, warnings, extractedComments };
+      }
+  })
+]
+```
+
+By default plugin use `uglify-es` package.
+
+Examples:
+
+#### `uglify-js`
+
+```bash
+npm i -D uglify-js
+```
+
+**webpack.config.js**
+```js
+[
+  new UglifyJsPlugin({
+    // Uncomment lines below for cache invalidation correctly
+    // cache: true,
+    // cacheKeys(defaultCacheKeys) {
+    //   return Object.assign(
+    //     {},
+    //     defaultCacheKeys,
+    //     { 'uglify-js': require('uglify-js/package.json').version },
+    //   );
+    // },
+    minify(file, sourceMap) {
+      // Look https://github.com/mishoo/UglifyJS2#minify-options
+      const uglifyJsOptions = { /* your `uglify-js` package options */ };
+
+      if (sourceMap) {
+        uglifyJsOptions.sourceMap = {
+          content: sourceMap,
+        };
+      }
+
+      return require('uglify-js').minify(file, uglifyJsOptions);
+    }
+  })
+]
+```
+
+#### `terser`
+
+```bash
+npm i -D terser
+```
+
+**webpack.config.js**
+```js
+[
+  new UglifyJsPlugin({
+    // Uncomment lines below for cache invalidation correctly
+    // cache: true,
+    // cacheKeys(defaultCacheKeys) {
+    //   return Object.assign(
+    //     {},
+    //     defaultCacheKeys,
+    //     { terser: require('terser/package.json').version },
+    //   );
+    // },
+    minify(file, sourceMap) {
+      // Look https://github.com/fabiosantoscode/terser#minify-options
+      const terserOptions = { /* your `terser` package options */ };
+
+      if (sourceMap) {
+        terserOption.sourceMap = {
+          content: sourceMap,
+        };
+      }
+
+      return require('terser').minify(file, terserOptions);
+    }
+  })
+]
+```
+
 ### [`uglifyOptions`](https://github.com/mishoo/UglifyJS2/tree/harmony#minify-options)
 
 |Name|Type|Default|Description|

package.json

@@ -57,6 +57,8 @@
     "nsp": "^3.1.0",
     "pre-commit": "^1.2.2",
     "standard-version": "^4.3.0",
+    "terser": "^3.7.6",
+    "uglify-js": "^3.4.3",
     "webpack": "^3.10.0",
     "webpack-defaults": "^1.6.0"
   },

src/index.js

@@ -9,7 +9,7 @@ import RequestShortener from 'webpack/lib/RequestShortener';
 import ModuleFilenameHelpers from 'webpack/lib/ModuleFilenameHelpers';
 import validateOptions from 'schema-utils';
 import schema from './options.json';
-import Uglify from './uglify';
+import Runner from './uglify/Runner';
 import versions from './uglify/versions';
 import utils from './utils';
 
@@ -20,6 +20,7 @@ class UglifyJsPlugin {
     validateOptions(schema, options, 'UglifyJs Plugin');
 
     const {
+      minify,
       uglifyOptions = {},
       test = /\.js(\?.*)?$/i,
       warningsFilter = () => true,
@@ -42,6 +43,7 @@ class UglifyJsPlugin {
       parallel,
       include,
       exclude,
+      minify,
       uglifyOptions: {
         compress: {
           inline: 1,
@@ -114,7 +116,7 @@ class UglifyJsPlugin {
     };
 
     const optimizeFn = (compilation, chunks, callback) => {
-      const uglify = new Uglify({
+      const runner = new Runner({
         cache: this.options.cache,
         parallel: this.options.parallel,
       });
@@ -169,6 +171,7 @@ class UglifyJsPlugin {
               commentsFile,
               extractComments: this.options.extractComments,
               uglifyOptions: this.options.uglifyOptions,
+              minify: this.options.minify,
             };
 
             if (this.options.cache) {
@@ -196,7 +199,7 @@ class UglifyJsPlugin {
           }
         });
 
-      uglify.runTasks(tasks, (tasksError, results) => {
+      runner.runTasks(tasks, (tasksError, results) => {
         if (tasksError) {
           compilation.errors.push(tasksError);
           return;
@@ -294,7 +297,7 @@ class UglifyJsPlugin {
           }
         });
 
-        uglify.exit();
+        runner.exit();
 
         callback();
       });

src/options.json

@@ -24,6 +24,9 @@
     "sourceMap": {
       "type": "boolean"
     },
+    "minify": {
+      "instanceof": "Function"
+    },
     "uglifyOptions": {
       "additionalProperties": true,
       "type": "object",

src/uglify/index.js → src/uglify/Runner.js

@@ -12,7 +12,7 @@ try {
   workerFile = require.resolve('../../dist/uglify/worker');
 } catch (e) { } // eslint-disable-line no-empty
 
-export default class {
+export default class Runner {
   constructor(options = {}) {
     const { cache, parallel } = options;
     this.cacheDir = cache === true ? findCacheDir({ name: 'uglifyjs-webpack-plugin' }) : cache;

src/uglify/minify.js

@@ -127,7 +127,12 @@ const buildComments = (options, uglifyOptions, extractedComments) => {
 };
 
 const minify = (options) => {
-  const { file, input, inputSourceMap, extractComments } = options;
+  const { file, input, inputSourceMap, extractComments, minify: minifyFn } = options;
+
+  if (minifyFn) {
+    return minifyFn({ [file]: input }, inputSourceMap);
+  }
+
   // Copy uglify options
   const uglifyOptions = buildUglifyOptions(options.uglifyOptions);