Add option to trigger JS framework-specific installation as part of webpack setup

railties/CHANGELOG.md

+*   Add Webpack support in new apps via the --webpack option, which will delegate to the rails/webpacker gem.
+
+    To generate a new app that has Webpack dependencies configured and binstubs for webpack and webpack-watcher:
+
+      rails new myapp --webpack
+
+    To generate a new app that has Webpack + React configured and an example intalled:
+    
+      rails new myapp --webpack=react
+    
+    *DHH*
+
 *   Add Yarn support in new apps with a yarn binstub and vendor/package.json. Skippable via --skip-yarn option.
 
     *Liceth Ovalles*, *Guillermo Iguaran*, *DHH*

railties/lib/rails/generators/app_base.rb

@@ -33,7 +33,7 @@ def self.add_shared_options_for(name)
         class_option :javascript,         type: :string, aliases: "-j",
                                           desc: "Preconfigure for selected JavaScript library"
 
-        class_option :webpack,            type: :boolean, default: false,
+        class_option :webpack,            type: :string, default: "base",
                                           desc: "Preconfigure for app-like JavaScript with Webpack"
 
         class_option :skip_yarn,          type: :boolean, default: false,
@@ -426,7 +426,10 @@ def run_bundle
       end
 
       def run_webpack
-        rails_command "webpacker:install" if options[:webpack]
+        if !(webpack = options[:webpack]).nil?
+          rails_command "webpacker:install"
+          rails_command "webpacker:install:#{webpack}" unless webpack == "base"
+        end
       end
 
       def generate_spring_binstubs