Add an enabled option

README.md

@@ -51,6 +51,7 @@ The constructor takes a configuration object with the following properties.
 | `outputPath` | string | The path (relative to your Webpack `outputPath`) to store externals copied over by this plugin. | `vendor` |
 | `publicPath` | string \| null | Override Webpack config's `publicPath` for the externals files, or `null` to use the default `output.publicPath` value. | `null` |
 | `files` | string \| array<string> \| null | If you have multiple instances of HtmlWebpackPlugin, use this to specify globs of which files you want to inject assets into. Will add assets to all files by default. | `null` |
+| `enabled` | boolean | Set to `false` to disable the plugin (useful for disabling in development mode). | `true` |
 
 ## Examples
 
@@ -285,3 +286,20 @@ new HtmlWebpackExternalsPlugin({
   files: ['about.html'],
 })
 ```
+
+### Disabling the plugin
+
+Sometimes you only want the plugin to be activated in certain environments. Rather than create separate Webpack configs or mess with splicing the plugins array, simply set the `enabled` option to `false` to disable the externals plugin entirely.
+
+```js
+new HtmlWebpackExternalsPlugin({
+  externals: [
+    {
+      module: 'jquery',
+      entry: 'dist/jquery.min.js',
+      global: 'jQuery',
+    },
+  ],
+  enabled: process.env.NODE_ENV === 'production',
+})
+```

package.json

@@ -30,6 +30,7 @@
   },
   "homepage": "https://github.com/mmiller42/html-webpack-externals-plugin#readme",
   "devDependencies": {
+    "assertion-error": "^1.0.2",
     "babel-cli": "^6.24.1",
     "babel-core": "^6.25.0",
     "babel-plugin-add-module-exports": "^0.2.1",

src/HtmlWebpackExternalsPlugin.js

@@ -25,11 +25,12 @@ export default class HtmlWebpackExternalsPlugin {
     this.assetsToCopy = []
     this.externals = {}
 
-    const { externals, hash, outputPath, publicPath, files } = config
+    const { externals, hash, outputPath, publicPath, files, enabled } = config
     this.hash = hash
     this.outputPath = outputPath
     this.publicPath = publicPath
     this.files = files
+    this.enabled = enabled
 
     externals.forEach(({ module, entry, global, supplements, append }) => {
       this.externals[module] = global
@@ -63,6 +64,10 @@ export default class HtmlWebpackExternalsPlugin {
   }
 
   apply(compiler) {
+    if (!this.enabled) {
+      return
+    }
+
     if (!compiler.options.externals) {
       compiler.options.externals = this.externals
     } else if (Array.isArray(compiler.options.externals)) {

src/configSchema.json

@@ -75,6 +75,10 @@
       },
       "minItems": 1,
       "default": null
+    },
+    "enabled": {
+      "type": "boolean",
+      "default": true
     }
   },
   "required": ["externals"]

test/HtmlWebpackExternalsPlugin.spec.js

@@ -1,4 +1,5 @@
 import assert from 'assert'
+import AssertionError from 'assertion-error'
 import HtmlWebpackPlugin from 'html-webpack-plugin'
 import HtmlWebpackExternalsPlugin from '../lib/'
 import {
@@ -288,11 +289,58 @@ describe('HtmlWebpackExternalsPlugin', function() {
           )
             .then(() =>
               reject(
-                'index.html should not have had the assets inserted into the HTML'
+                new AssertionError(
+                  'index.html should not have had the assets inserted into the HTML'
+                )
               )
             )
-            .catch(() => resolve())
+            .catch(resolve)
         })
       })
   })
+
+  it('does not run when enabled is false', function() {
+    const wp = runWebpack(
+      new HtmlWebpackPlugin(),
+      new HtmlWebpackExternalsPlugin({
+        externals: [
+          {
+            module: 'jquery',
+            entry: 'dist/jquery.min.js',
+            global: 'jQuery',
+          },
+        ],
+        enabled: false,
+      })
+    )
+
+    return Promise.all([
+      new Promise((resolve, reject) => {
+        wp
+          .then(() => checkBundleExcludes('jQuery'))
+          .then(() =>
+            reject(new AssertionError('Plugin should not have excluded jQuery'))
+          )
+          .catch(resolve)
+      }),
+      new Promise((resolve, reject) => {
+        wp
+          .then(() => checkCopied('vendor/jquery/dist/jquery.min.js'))
+          .then(() =>
+            reject(new AssertionError('Plugin should not have copied jQuery'))
+          )
+          .catch(resolve)
+      }),
+      new Promise((resolve, reject) => {
+        wp
+          .then(() =>
+            checkHtmlIncludes('vendor/jquery/dist/jquery.min.js', 'js')
+          )
+          .then(() =>
+            reject(new AssertionError('Plugin should not have injected jQuery'))
+          )
+          .catch(resolve)
+      }),
+    ])
+  })
 })