Make mix.webpackConfig() run *after* extensions - closes #2439

src/builder/WebpackConfig.js

@@ -27,7 +27,6 @@ class WebpackConfig {
         await this.buildRules();
         await this.buildPlugins();
         this.buildChunks();
-        this.mergeCustomConfig();
 
         // We'll announce that the core config object has been
         // generated by Mix. At this point, any plugins may
@@ -175,18 +174,6 @@ class WebpackConfig {
             this.chunks.config()
         );
     }
-
-    /**
-     * Merge the user's custom Webpack configuration.
-     */
-    mergeCustomConfig() {
-        if (Config.webpackConfig) {
-            this.webpackConfig = require('./MergeWebpackConfig')(
-                this.webpackConfig,
-                Config.webpackConfig
-            );
-        }
-    }
 }
 
 module.exports = WebpackConfig;

src/components/WebpackConfig.js

@@ -1,15 +1,12 @@
-let webpack = require('webpack');
+let merge = require('../builder/MergeWebpackConfig');
 
 class WebpackConfig {
     register(config) {
-        config = typeof config == 'function' ? config(webpack) : config;
+        mix.override(webpackConfig => {
+            config = typeof config == 'function' ? config(webpackConfig) : config;
 
-        Config.webpackConfig = require('../builder/MergeWebpackConfig')(
-            Config.webpackConfig,
-            config
-        );
-
-        return this;
+            Object.assign(webpackConfig, merge(webpackConfig, config));
+        });
     }
 }
 

test/features/webpackConfig.js

@@ -3,31 +3,13 @@ import test from 'ava';
 import '../helpers/mix';
 import { buildConfig } from '../helpers/webpack';
 
-test('mix.webpackConfig()', t => {
-    // Test config passed as an object.
-    let config = { context: 'changed' };
-    let response = mix.webpackConfig(config);
-
-    t.deepEqual(mix, response);
-
-    t.deepEqual(config, Config.webpackConfig);
-
-    // Test config passed via a callback.
-    config = { context: 'changed again' };
-    response = mix.webpackConfig(webpack => config);
-
-    t.deepEqual(mix, response);
-
-    t.deepEqual(config, Config.webpackConfig);
-});
-
-test('Custom user config can be merged', async t => {
+test('Custom webpack config can be merged', async t => {
     mix.webpackConfig({ context: 'changed' });
 
     t.is('changed', (await buildConfig()).context);
 });
 
-test('Custom user config can be merged as a callback function', async t => {
+test('Custom webpack config can be merged as a callback function', async t => {
     mix.webpackConfig(webpack => {
         return {
             context: 'changed'
@@ -36,3 +18,19 @@ test('Custom user config can be merged as a callback function', async t => {
 
     t.is('changed', (await buildConfig()).context);
 });
+
+test('Custom webpack config is called and merged *after* all plugins and extensions', async t => {
+    mix.extend('extension', {
+        webpackConfig(config) {
+            config.foo = 'extension foo';
+        }
+    });
+
+    mix.extension().webpackConfig(() => {
+        return {
+            foo: 'webpackConfig foo'
+        };
+    });
+
+    t.is('webpackConfig foo', (await buildConfig()).foo);
+});