Fix bin/dev pack generation in Bundler context

lib/react_on_rails/dev/pack_generator.rb

@@ -9,10 +9,10 @@ class << self
         def generate(verbose: false)
           if verbose
             puts "📦 Generating React on Rails packs..."
-            success = system "bundle exec rake react_on_rails:generate_packs"
+            success = run_pack_generation
           else
             print "📦 Generating packs... "
-            success = system "bundle exec rake react_on_rails:generate_packs > /dev/null 2>&1"
+            success = run_pack_generation(silent: true)
             puts success ? "✅" : "❌"
           end
 
@@ -21,6 +21,100 @@ def generate(verbose: false)
           puts "❌ Pack generation failed"
           exit 1
         end
+
+        private
+
+        def run_pack_generation(silent: false)
+          # If we're already inside a Bundler context AND Rails is available (e.g., called from bin/dev),
+          # we can directly require and run the task. Otherwise, use bundle exec.
+          if should_run_directly?
+            run_rake_task_directly(silent: silent)
+          else
+            run_via_bundle_exec(silent: silent)
+          end
+        end
+
+        def should_run_directly?
+          # Check if we're in a meaningful Bundler context with BUNDLE_GEMFILE
+          return false unless defined?(Bundler)
+          return false unless ENV["BUNDLE_GEMFILE"]
+          return false unless rails_available?
+
+          true
+        end
+
+        def rails_available?
+          return false unless defined?(Rails)
+          return false unless Rails.respond_to?(:application)
+          return false if Rails.application.nil?
+
+          # Verify Rails app can actually load tasks
+          begin
+            Rails.application.respond_to?(:load_tasks)
+          rescue StandardError
+            false
+          end
+        end
+
+        def run_rake_task_directly(silent: false)
+          require "rake"
+
+          load_rake_tasks
+          task = prepare_rake_task
+
+          capture_output(silent) do
+            task.invoke
+            true
+          end
+        rescue StandardError => e
+          handle_rake_error(e, silent)
+          false
+        end
+
+        def load_rake_tasks
+          return if Rake::Task.task_defined?("react_on_rails:generate_packs")
+
+          Rails.application.load_tasks
+        end
+
+        def prepare_rake_task
+          task = Rake::Task["react_on_rails:generate_packs"]
+          task.reenable # Allow re-execution if called multiple times
+          task
+        end
+
+        def capture_output(silent)
+          return yield unless silent
+
+          original_stdout = $stdout
+          original_stderr = $stderr
+          output_buffer = StringIO.new
+          $stdout = output_buffer
+          $stderr = output_buffer
+
+          begin
+            yield
+          ensure
+            $stdout = original_stdout
+            $stderr = original_stderr
+          end
+        end
+
+        def handle_rake_error(error, _silent)
+          error_msg = "Error generating packs: #{error.message}"
+          error_msg += "\n#{error.backtrace.join("\n")}" if ENV["DEBUG"]
+
+          # Always write to stderr, even in silent mode
+          warn error_msg
+        end
+
+        def run_via_bundle_exec(silent: false)
+          if silent
+            system "bundle exec rake react_on_rails:generate_packs > /dev/null 2>&1"
+          else
+            system "bundle exec rake react_on_rails:generate_packs"
+          end
+        end
       end
     end
   end