chore: check for existing arr

Author: evenstensberg

lib/groups/advanced.js

@@ -43,8 +43,13 @@ class AdvancedGroup extends GroupHelper {
     resolveOptions() {
         const { args } = this;
         if (args.hot) {
-            const HotModuleReplacementPlugin = require('webpack').HotModuleReplacementPlugin;
-            this.opts.options.plugins = [new HotModuleReplacementPlugin()];
+            const { HotModuleReplacementPlugin } = require('webpack');
+            const hotModuleVal = new HotModuleReplacementPlugin();
+            if (this.opts.options && this.opts.options.plugins) {
+                this.opts.options.plugins.unshift(hotModuleVal);
+            } else {
+                this.opts.options.plugins = [hotModuleVal];
+            }
         }
         if (args.prefetch) {
             const { PrefetchPlugin } = require('webpack');