Allow to replace options in configuration callbacks

Author: Lyrkan

lib/loaders/babel.js

@@ -68,11 +68,15 @@ module.exports = {
             }
 
             // allow for babel config to be controlled
-            webpackConfig.babelConfigurationCallback.apply(
+            const callbackResult = webpackConfig.babelConfigurationCallback.apply(
                 // use babelConfig as the this variable
                 babelConfig,
                 [babelConfig]
             );
+
+            if (callbackResult instanceof Object) {
+                babelConfig = callbackResult;
+            }
         }
 
         return [

lib/loaders/coffee-script.js

@@ -19,19 +19,23 @@ module.exports = {
     getLoaders(webpackConfig) {
         loaderFeatures.ensurePackagesExist('coffeescript');
 
-        const options = {
+        let options = {
             sourceMap: webpackConfig.useSourceMaps,
             transpile: {
                 presets: ['env']
             }
         };
 
         // allow options to be configured
-        webpackConfig.coffeeScriptConfigurationCallback.apply(
+        const callbackResult = webpackConfig.coffeeScriptConfigurationCallback.apply(
             options,
             [options]
         );
 
+        if (callbackResult instanceof Object) {
+            options = callbackResult;
+        }
+
         return [
             {
                 loader: 'coffee-loader',

lib/loaders/css.js

@@ -38,17 +38,21 @@ module.exports = {
         if (usePostCssLoader) {
             loaderFeatures.ensurePackagesExist('postcss');
 
-            const postCssLoaderOptions = {
+            let postCssLoaderOptions = {
                 sourceMap: webpackConfig.useSourceMaps
             };
 
             // allow options to be configured
-            webpackConfig.postCssLoaderOptionsCallback.apply(
+            const callbackResult = webpackConfig.postCssLoaderOptionsCallback.apply(
                 // use config as the this variable
                 postCssLoaderOptions,
                 [postCssLoaderOptions]
             );
 
+            if (callbackResult instanceof Object) {
+                postCssLoaderOptions = callbackResult;
+            }
+
             cssLoaders.push({
                 loader: 'postcss-loader',
                 options: postCssLoaderOptions

lib/loaders/less.js

@@ -21,17 +21,21 @@ module.exports = {
     getLoaders(webpackConfig, ignorePostCssLoader = false) {
         loaderFeatures.ensurePackagesExist('less');
 
-        const config = {
+        let config = {
             sourceMap: webpackConfig.useSourceMaps
         };
 
         // allow options to be configured
-        webpackConfig.lessLoaderOptionsCallback.apply(
+        const callbackResult = webpackConfig.lessLoaderOptionsCallback.apply(
             // use config as the this variable
             config,
             [config]
         );
 
+        if (callbackResult instanceof Object) {
+            config = callbackResult;
+        }
+
         return [
             ...cssLoader.getLoaders(webpackConfig, ignorePostCssLoader),
             {

lib/loaders/sass.js

@@ -41,12 +41,16 @@ module.exports = {
         });
 
         // allow options to be configured
-        webpackConfig.sassLoaderOptionsCallback.apply(
+        const callbackResult = webpackConfig.sassLoaderOptionsCallback.apply(
             // use config as the this variable
             config,
             [config]
         );
 
+        if (callbackResult instanceof Object) {
+            config = callbackResult;
+        }
+
         sassLoaders.push({
             loader: 'sass-loader',
             options: config,

lib/loaders/stylus.js

@@ -21,17 +21,21 @@ module.exports = {
     getLoaders(webpackConfig, ignorePostCssLoader = false) {
         loaderFeatures.ensurePackagesExist('stylus');
 
-        const config = {
+        let config = {
             sourceMap: webpackConfig.useSourceMaps
         };
 
         // allow options to be configured
-        webpackConfig.stylusLoaderOptionsCallback.apply(
+        const callbackResult = webpackConfig.stylusLoaderOptionsCallback.apply(
             // use config as the this variable
             config,
             [config]
         );
 
+        if (callbackResult instanceof Object) {
+            config = callbackResult;
+        }
+
         return [
             ...cssLoader.getLoaders(webpackConfig, ignorePostCssLoader),
             {

lib/loaders/typescript.js

@@ -26,12 +26,16 @@ module.exports = {
         };
 
         // allow for ts-loader config to be controlled
-        webpackConfig.tsConfigurationCallback.apply(
+        const callbackResult = webpackConfig.tsConfigurationCallback.apply(
             // use config as the this variable
             config,
             [config]
         );
 
+        if (callbackResult instanceof Object) {
+            config = callbackResult;
+        }
+
         // fork-ts-checker-webpack-plugin integration
         if (webpackConfig.useForkedTypeScriptTypeChecking) {
             loaderFeatures.ensurePackagesExist('forkedtypecheck');

lib/loaders/vue.js

@@ -120,8 +120,13 @@ module.exports = {
         let options = {
             loaders: loaders
         };
+
         // allow the options to be mutated via a callback
-        vueLoaderOptionsCallback(options);
+        const callbackResult = vueLoaderOptionsCallback(options);
+
+        if (callbackResult instanceof Object) {
+            options = callbackResult;
+        }
 
         return [
             {

lib/plugins/clean.js

@@ -25,16 +25,20 @@ module.exports = function(plugins, webpackConfig) {
         return;
     }
 
-    const cleanWebpackPluginOptions = {
+    let cleanWebpackPluginOptions = {
         root: webpackConfig.outputPath,
         verbose: false,
     };
 
-    webpackConfig.cleanWebpackPluginOptionsCallback.apply(
+    const callbackResult = webpackConfig.cleanWebpackPluginOptionsCallback.apply(
         cleanWebpackPluginOptions,
         [cleanWebpackPluginOptions]
     );
 
+    if (callbackResult instanceof Object) {
+        cleanWebpackPluginOptions = callbackResult;
+    }
+
     plugins.push({
         plugin: new CleanWebpackPlugin(
             webpackConfig.cleanWebpackPluginPaths,

lib/plugins/define.js

@@ -18,17 +18,21 @@ const PluginPriorities = require('./plugin-priorities');
  * @return {void}
  */
 module.exports = function(plugins, webpackConfig) {
-    const definePluginOptions = {
+    let definePluginOptions = {
         'process.env': {
             NODE_ENV: webpackConfig.isProduction() ? '"production"' : '"development"'
         }
     };
 
-    webpackConfig.definePluginOptionsCallback.apply(
+    const callbackResult = webpackConfig.definePluginOptionsCallback.apply(
         definePluginOptions,
         [definePluginOptions]
     );
 
+    if (callbackResult instanceof Object) {
+        definePluginOptions = callbackResult;
+    }
+
     plugins.push({
         plugin: new webpack.DefinePlugin(definePluginOptions),
         priority: PluginPriorities.DefinePlugin