Generate --rspack configs under config/rspack

react_on_rails/lib/generators/react_on_rails/base_generator.rb

@@ -70,7 +70,7 @@ def copy_js_bundle_files
       end
 
       def copy_webpack_config
-        puts "Adding Webpack config"
+        puts "Adding #{options.rspack? ? 'Rspack' : 'Webpack'} config"
         base_path = "base/base"
         base_files = %w[babel.config.js
                         config/webpack/clientWebpackConfig.js
@@ -83,7 +83,9 @@ def copy_webpack_config
         config = {
           message: "// The source code including full typescript support is available at:"
         }
-        base_files.each { |file| template("#{base_path}/#{file}.tt", file, config) }
+        base_files.each do |file|
+          template("#{base_path}/#{file}.tt", destination_config_path(file), config)
+        end
 
         # Handle webpack.config.js separately with smart replacement
         copy_webpack_main_config(base_path, config)
@@ -155,7 +157,7 @@ def append_to_spec_rails_helper
       private
 
       def copy_webpack_main_config(base_path, config)
-        webpack_config_path = "config/webpack/webpack.config.js"
+        webpack_config_path = bundler_main_config_path
 
         if File.exist?(webpack_config_path)
           existing_content = File.read(webpack_config_path)
@@ -167,7 +169,7 @@ def copy_webpack_main_config(base_path, config)
             # Show what we're doing
             puts "   #{set_color('replace', :green)}  #{webpack_config_path} " \
                  "(auto-upgrading from standard Shakapacker to React on Rails config)"
-            template("#{base_path}/#{webpack_config_path}.tt", webpack_config_path, config)
+            template("#{base_path}/config/webpack/webpack.config.js.tt", webpack_config_path, config)
           elsif react_on_rails_config?(existing_content)
             puts "   #{set_color('identical', :blue)}  #{webpack_config_path} " \
                  "(already React on Rails compatible)"
@@ -177,29 +179,45 @@ def copy_webpack_main_config(base_path, config)
           end
         else
           # File doesn't exist, create it
-          template("#{base_path}/#{webpack_config_path}.tt", webpack_config_path, config)
+          template("#{base_path}/config/webpack/webpack.config.js.tt", webpack_config_path, config)
         end
       end
 
       def handle_custom_webpack_config(base_path, config, webpack_config_path)
         # Custom config - ask user
-        puts "\n#{set_color('NOTICE:', :yellow)} Your webpack.config.js appears to be customized."
+        config_file_name = File.basename(webpack_config_path)
+        bundler_name = options.rspack? ? "rspack" : "webpack"
+        puts "\n#{set_color('NOTICE:', :yellow)} Your #{config_file_name} appears to be customized."
         puts "React on Rails needs to replace it with an environment-specific loader."
-        puts "Your current config will be backed up to webpack.config.js.backup"
+        puts "Your current config will be backed up to #{config_file_name}.backup"
 
-        if yes?("Replace webpack.config.js with React on Rails version? (Y/n)")
+        if yes?("Replace #{config_file_name} with React on Rails version? (Y/n)")
           # Create backup
           backup_path = "#{webpack_config_path}.backup"
           if File.exist?(webpack_config_path)
             FileUtils.cp(webpack_config_path, backup_path)
             puts "   #{set_color('create', :green)}  #{backup_path} (backup of your custom config)"
           end
 
-          template("#{base_path}/#{webpack_config_path}.tt", webpack_config_path, config)
+          template("#{base_path}/config/webpack/webpack.config.js.tt", webpack_config_path, config)
         else
           puts "   #{set_color('skip', :yellow)}  #{webpack_config_path}"
           puts "   #{set_color('WARNING:', :red)} React on Rails may not work correctly " \
-               "without the environment-specific webpack config"
+               "without the environment-specific #{bundler_name} config"
+        end
+      end
+
+      def destination_config_path(path)
+        return path unless options.rspack?
+
+        path.sub("config/webpack/", "config/rspack/")
+      end
+
+      def bundler_main_config_path
+        if options.rspack?
+          "config/rspack/rspack.config.js"
+        else
+          "config/webpack/webpack.config.js"
         end
       end
 

react_on_rails/lib/generators/react_on_rails/install_generator.rb

@@ -251,7 +251,13 @@ def shakapacker_configured?
         # Check for essential shakapacker configuration files and binaries
         shakapacker_binaries_exist? &&
           File.exist?("config/shakapacker.yml") &&
-          File.exist?("config/webpack/webpack.config.js")
+          shakapacker_config_file_exists?
+      end
+
+      def shakapacker_config_file_exists?
+        File.exist?("config/webpack/webpack.config.js") ||
+          File.exist?("config/rspack/rspack.config.js") ||
+          File.exist?("config/rspack/rspack.config.ts")
       end
 
       def print_shakapacker_setup_banner

react_on_rails/spec/react_on_rails/generators/install_generator_spec.rb

@@ -305,24 +305,31 @@
       end
     end
 
-    it "generates unified webpack config with bundler detection" do
-      assert_file "config/webpack/development.js" do |content|
+    it "generates unified rspack config with bundler detection" do
+      assert_file "config/rspack/development.js" do |content|
         expect(content).to include("const { devServer, inliningCss, config } = require('shakapacker')")
         expect(content).to include("if (config.assets_bundler === 'rspack')")
         expect(content).to include("@rspack/plugin-react-refresh")
         expect(content).to include("@pmmmwh/react-refresh-webpack-plugin")
       end
     end
 
-    it "generates server webpack config with bundler variable" do
-      assert_file "config/webpack/serverWebpackConfig.js" do |content|
+    it "generates server rspack config with bundler variable" do
+      assert_file "config/rspack/serverWebpackConfig.js" do |content|
         expect(content).to include("const bundler = config.assets_bundler === 'rspack'")
         expect(content).to include("? require('@rspack/core')")
         expect(content).to include(": require('webpack')")
         expect(content).to include("new bundler.optimize.LimitChunkCountPlugin")
       end
     end
 
+    it "writes the main rspack config to config/rspack/rspack.config.js" do
+      assert_file "config/rspack/rspack.config.js" do |content|
+        expect(content).to include("const envSpecificConfig = () =>")
+        expect(content).to include("const path = resolve(__dirname, `${env.nodeEnv}.js`)")
+      end
+    end
+
     it "configures rspack in shakapacker.yml" do
       assert_file "config/shakapacker.yml" do |content|
         # Should have rspack as the bundler (inherited by all environments via YAML anchor)
@@ -497,6 +504,32 @@
     end
   end
 
+  describe "#shakapacker_configured?" do
+    let(:install_generator) { described_class.new }
+
+    before do
+      allow(File).to receive(:exist?).and_call_original
+      allow(install_generator).to receive(:shakapacker_binaries_exist?).and_return(true)
+      allow(File).to receive(:exist?).with("config/shakapacker.yml").and_return(true)
+    end
+
+    it "returns true when rspack config exists in config/rspack" do
+      allow(File).to receive(:exist?).with("config/webpack/webpack.config.js").and_return(false)
+      allow(File).to receive(:exist?).with("config/rspack/rspack.config.js").and_return(true)
+      allow(File).to receive(:exist?).with("config/rspack/rspack.config.ts").and_return(false)
+
+      expect(install_generator.send(:shakapacker_configured?)).to be true
+    end
+
+    it "returns false when no supported bundler config file exists" do
+      allow(File).to receive(:exist?).with("config/webpack/webpack.config.js").and_return(false)
+      allow(File).to receive(:exist?).with("config/rspack/rspack.config.js").and_return(false)
+      allow(File).to receive(:exist?).with("config/rspack/rspack.config.ts").and_return(false)
+
+      expect(install_generator.send(:shakapacker_configured?)).to be false
+    end
+  end
+
   # Regression test for https://github.com/shakacode/react_on_rails/issues/2287
   # Bundler subprocess commands must run in unbundled environment to prevent
   # BUNDLE_GEMFILE inheritance from parent process