From 95f738593e7752eb63792251596d6ea969edc3a3 Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 16:01:24 +0900
Subject: [PATCH 01/13] refactor: move tests to spec/ruby_wasm_ui/runtime
 directory

---
 spec/ruby_wasm_ui/{ => runtime}/component_spec.rb                 | 0
 spec/ruby_wasm_ui/{ => runtime}/dom/scheduler_spec.rb             | 0
 spec/ruby_wasm_ui/{ => runtime}/nodes_equal_spec.rb               | 0
 .../{ => runtime}/template/build_conditional_group_spec.rb        | 0
 spec/ruby_wasm_ui/{ => runtime}/template/build_for_group_spec.rb  | 0
 spec/ruby_wasm_ui/{ => runtime}/template/build_vdom_spec.rb       | 0
 spec/ruby_wasm_ui/{ => runtime}/template/parser_spec.rb           | 0
 spec/ruby_wasm_ui/{ => runtime}/utils/arrays_spec.rb              | 0
 spec/ruby_wasm_ui/{ => runtime}/utils/objects_spec.rb             | 0
 spec/ruby_wasm_ui/{ => runtime}/utils/props_spec.rb               | 0
 spec/ruby_wasm_ui/{ => runtime}/utils/strings_spec.rb             | 0
 11 files changed, 0 insertions(+), 0 deletions(-)
 rename spec/ruby_wasm_ui/{ => runtime}/component_spec.rb (100%)
 rename spec/ruby_wasm_ui/{ => runtime}/dom/scheduler_spec.rb (100%)
 rename spec/ruby_wasm_ui/{ => runtime}/nodes_equal_spec.rb (100%)
 rename spec/ruby_wasm_ui/{ => runtime}/template/build_conditional_group_spec.rb (100%)
 rename spec/ruby_wasm_ui/{ => runtime}/template/build_for_group_spec.rb (100%)
 rename spec/ruby_wasm_ui/{ => runtime}/template/build_vdom_spec.rb (100%)
 rename spec/ruby_wasm_ui/{ => runtime}/template/parser_spec.rb (100%)
 rename spec/ruby_wasm_ui/{ => runtime}/utils/arrays_spec.rb (100%)
 rename spec/ruby_wasm_ui/{ => runtime}/utils/objects_spec.rb (100%)
 rename spec/ruby_wasm_ui/{ => runtime}/utils/props_spec.rb (100%)
 rename spec/ruby_wasm_ui/{ => runtime}/utils/strings_spec.rb (100%)

diff --git a/spec/ruby_wasm_ui/component_spec.rb b/spec/ruby_wasm_ui/runtime/component_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/component_spec.rb
rename to spec/ruby_wasm_ui/runtime/component_spec.rb
diff --git a/spec/ruby_wasm_ui/dom/scheduler_spec.rb b/spec/ruby_wasm_ui/runtime/dom/scheduler_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/dom/scheduler_spec.rb
rename to spec/ruby_wasm_ui/runtime/dom/scheduler_spec.rb
diff --git a/spec/ruby_wasm_ui/nodes_equal_spec.rb b/spec/ruby_wasm_ui/runtime/nodes_equal_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/nodes_equal_spec.rb
rename to spec/ruby_wasm_ui/runtime/nodes_equal_spec.rb
diff --git a/spec/ruby_wasm_ui/template/build_conditional_group_spec.rb b/spec/ruby_wasm_ui/runtime/template/build_conditional_group_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/template/build_conditional_group_spec.rb
rename to spec/ruby_wasm_ui/runtime/template/build_conditional_group_spec.rb
diff --git a/spec/ruby_wasm_ui/template/build_for_group_spec.rb b/spec/ruby_wasm_ui/runtime/template/build_for_group_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/template/build_for_group_spec.rb
rename to spec/ruby_wasm_ui/runtime/template/build_for_group_spec.rb
diff --git a/spec/ruby_wasm_ui/template/build_vdom_spec.rb b/spec/ruby_wasm_ui/runtime/template/build_vdom_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/template/build_vdom_spec.rb
rename to spec/ruby_wasm_ui/runtime/template/build_vdom_spec.rb
diff --git a/spec/ruby_wasm_ui/template/parser_spec.rb b/spec/ruby_wasm_ui/runtime/template/parser_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/template/parser_spec.rb
rename to spec/ruby_wasm_ui/runtime/template/parser_spec.rb
diff --git a/spec/ruby_wasm_ui/utils/arrays_spec.rb b/spec/ruby_wasm_ui/runtime/utils/arrays_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/utils/arrays_spec.rb
rename to spec/ruby_wasm_ui/runtime/utils/arrays_spec.rb
diff --git a/spec/ruby_wasm_ui/utils/objects_spec.rb b/spec/ruby_wasm_ui/runtime/utils/objects_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/utils/objects_spec.rb
rename to spec/ruby_wasm_ui/runtime/utils/objects_spec.rb
diff --git a/spec/ruby_wasm_ui/utils/props_spec.rb b/spec/ruby_wasm_ui/runtime/utils/props_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/utils/props_spec.rb
rename to spec/ruby_wasm_ui/runtime/utils/props_spec.rb
diff --git a/spec/ruby_wasm_ui/utils/strings_spec.rb b/spec/ruby_wasm_ui/runtime/utils/strings_spec.rb
similarity index 100%
rename from spec/ruby_wasm_ui/utils/strings_spec.rb
rename to spec/ruby_wasm_ui/runtime/utils/strings_spec.rb

From b4100f22dceb618595db17b54de2423f0ee62c3a Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 16:08:53 +0900
Subject: [PATCH 02/13] feat: Add setup command

---
 examples/.gitignore                         |   3 +
 exe/ruby-wasm-ui                            |   6 ++
 lib/ruby_wasm_ui/cli/command.rb             |  48 +++++++++
 lib/ruby_wasm_ui/cli/command/base.rb        | 103 ++++++++++++++++++++
 lib/ruby_wasm_ui/cli/command/setup.rb       |  34 +++++++
 spec/ruby_wasm_ui/cli/command/base_spec.rb  |  94 ++++++++++++++++++
 spec/ruby_wasm_ui/cli/command/setup_spec.rb |  55 +++++++++++
 spec/ruby_wasm_ui/cli/command_spec.rb       |  64 ++++++++++++
 8 files changed, 407 insertions(+)
 create mode 100644 examples/.gitignore
 create mode 100755 exe/ruby-wasm-ui
 create mode 100644 lib/ruby_wasm_ui/cli/command.rb
 create mode 100644 lib/ruby_wasm_ui/cli/command/base.rb
 create mode 100644 lib/ruby_wasm_ui/cli/command/setup.rb
 create mode 100644 spec/ruby_wasm_ui/cli/command/base_spec.rb
 create mode 100644 spec/ruby_wasm_ui/cli/command/setup_spec.rb
 create mode 100644 spec/ruby_wasm_ui/cli/command_spec.rb

diff --git a/examples/.gitignore b/examples/.gitignore
new file mode 100644
index 0000000..64fd3c0
--- /dev/null
+++ b/examples/.gitignore
@@ -0,0 +1,3 @@
+*.wasm
+/rubies
+/build
diff --git a/exe/ruby-wasm-ui b/exe/ruby-wasm-ui
new file mode 100755
index 0000000..f4ff316
--- /dev/null
+++ b/exe/ruby-wasm-ui
@@ -0,0 +1,6 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+require_relative "../lib/ruby_wasm_ui/cli/command"
+
+RubyWasmUi::Cli::Command.run(ARGV)
diff --git a/lib/ruby_wasm_ui/cli/command.rb b/lib/ruby_wasm_ui/cli/command.rb
new file mode 100644
index 0000000..3bf0463
--- /dev/null
+++ b/lib/ruby_wasm_ui/cli/command.rb
@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+require_relative "command/setup"
+# To add a new command (e.g., dev):
+# 1. Create lib/ruby_wasm_ui/cli/command/dev.rb inheriting from Command::Base
+# 2. Add require_relative "command/dev" above
+# 3. Add "dev" => Command::Dev to COMMANDS hash below
+
+module RubyWasmUi
+  module Cli
+    class Command
+      COMMANDS = {
+        "setup" => Command::Setup
+        # Add new commands here, e.g.:
+        # "dev" => Command::Dev
+      }.freeze
+
+      def self.run(argv)
+        command_name = argv[0]
+
+        if command_name.nil?
+          show_usage
+          exit 1
+        end
+
+        command_class = COMMANDS[command_name]
+        if command_class.nil?
+          puts "Unknown command: #{command_name}"
+          puts ""
+          show_usage
+          exit 1
+        end
+
+        command_class.new.run(argv[1..-1])
+      end
+
+      def self.show_usage
+        puts "Usage: ruby-wasm-ui <command>"
+        puts ""
+        puts "Commands:"
+        COMMANDS.each do |name, klass|
+          description = klass.description || ""
+          puts "  #{name.ljust(12)}#{description}"
+        end
+      end
+    end
+  end
+end
diff --git a/lib/ruby_wasm_ui/cli/command/base.rb b/lib/ruby_wasm_ui/cli/command/base.rb
new file mode 100644
index 0000000..4d233ff
--- /dev/null
+++ b/lib/ruby_wasm_ui/cli/command/base.rb
@@ -0,0 +1,103 @@
+# frozen_string_literal: true
+
+require "open3"
+
+module RubyWasmUi
+  module Cli
+    class Command
+      class Base
+        def self.description
+          nil
+        end
+
+        def run(_argv)
+          raise NotImplementedError, "Subclasses must implement #run"
+        end
+
+        protected
+
+        def run_command(command)
+          log_debug("Executing command: #{command}")
+          
+          Open3.popen3(command) do |stdin, stdout, stderr, wait_thr|
+            stdin.close
+            
+            # Read stdout and stderr in separate threads for real-time output
+            stdout_thread = Thread.new do
+              stdout.each_line do |line|
+                print line
+                $stdout.flush
+              end
+            end
+            
+            stderr_thread = Thread.new do
+              stderr.each_line do |line|
+                $stderr.print line
+                $stderr.flush
+              end
+            end
+            
+            # Wait for both threads to finish reading
+            stdout_thread.join
+            stderr_thread.join
+            
+            # Wait for the process to finish
+            exit_status = wait_thr.value
+            
+            unless exit_status.success?
+              log_error("Command failed: #{command}")
+              exit exit_status.exitstatus
+            end
+          end
+        end
+
+        def update_gitignore(entries_to_add)
+          gitignore_path = ".gitignore"
+
+          # Read existing .gitignore or create new content
+          if File.exist?(gitignore_path)
+            content = File.read(gitignore_path)
+            lines = content.lines.map(&:chomp)
+          else
+            lines = []
+          end
+
+          # Add entries that don't already exist
+          added_entries = []
+          entries_to_add.each do |entry|
+            unless lines.include?(entry)
+              lines << entry
+              added_entries << entry
+            end
+          end
+
+          # Write back to .gitignore
+          File.write(gitignore_path, lines.join("\n") + "\n")
+          if added_entries.any?
+            log_info("Added to .gitignore: #{added_entries.join(', ')}")
+          else
+            log_info("No new entries added to .gitignore (all entries already exist)")
+          end
+        end
+
+        protected
+
+        def log_info(message)
+          puts "[INFO] #{message}"
+        end
+
+        def log_success(message)
+          puts "[SUCCESS] #{message}"
+        end
+
+        def log_error(message)
+          puts "[ERROR] #{message}"
+        end
+
+        def log_debug(message)
+          puts "[DEBUG] #{message}"
+        end
+      end
+    end
+  end
+end
diff --git a/lib/ruby_wasm_ui/cli/command/setup.rb b/lib/ruby_wasm_ui/cli/command/setup.rb
new file mode 100644
index 0000000..0ffb738
--- /dev/null
+++ b/lib/ruby_wasm_ui/cli/command/setup.rb
@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+require_relative "base"
+
+module RubyWasmUi
+  module Cli
+    class Command
+      class Setup < Base
+        def self.description
+          "Set up the project for ruby-wasm-ui"
+        end
+
+        def run(_argv)
+          log_info("Setting up ruby-wasm-ui project...")
+          puts ""
+
+          # Build Ruby WASM
+          log_info("Step 1/2: Building Ruby WASM...")
+          log_info("Running: bundle exec rbwasm build --ruby-version 3.4 -o ruby.wasm")
+          run_command("bundle exec rbwasm build --ruby-version 3.4 -o ruby.wasm")
+          log_success("✓ Ruby WASM build completed")
+
+          # Update .gitignore
+          puts ""
+          log_info("Step 2/2: Updating .gitignore...")
+          update_gitignore(["*.wasm", "/rubies", "/build"])
+
+          puts ""
+          log_success("Setup completed successfully!")
+        end
+      end
+    end
+  end
+end
diff --git a/spec/ruby_wasm_ui/cli/command/base_spec.rb b/spec/ruby_wasm_ui/cli/command/base_spec.rb
new file mode 100644
index 0000000..d4a05fa
--- /dev/null
+++ b/spec/ruby_wasm_ui/cli/command/base_spec.rb
@@ -0,0 +1,94 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require 'fileutils'
+require 'tmpdir'
+
+RSpec.describe RubyWasmUi::Cli::Command::Base do
+  let(:base_instance) { described_class.new }
+
+  describe '#run' do
+    it 'raises NotImplementedError' do
+      expect { base_instance.run([]) }.to raise_error(NotImplementedError, /Subclasses must implement #run/)
+    end
+  end
+
+  describe '#update_gitignore' do
+    let(:temp_dir) { Dir.mktmpdir }
+    let(:original_dir) { Dir.pwd }
+
+    around do |example|
+      Dir.chdir(temp_dir) do
+        example.run
+      end
+    ensure
+      FileUtils.rm_rf(temp_dir) if Dir.exist?(temp_dir)
+    end
+
+    context 'when .gitignore does not exist' do
+      it 'creates .gitignore with new entries' do
+        base_instance.send(:update_gitignore, ['*.wasm', '/rubies'])
+        content = File.read('.gitignore')
+        expect(content).to include('*.wasm')
+        expect(content).to include('/rubies')
+      end
+    end
+
+    context 'when .gitignore exists' do
+      before do
+        File.write('.gitignore', "node_modules/\n*.log\n")
+      end
+
+      it 'adds new entries to existing .gitignore' do
+        base_instance.send(:update_gitignore, ['*.wasm', '/rubies'])
+        content = File.read('.gitignore')
+        expect(content).to include('node_modules/')
+        expect(content).to include('*.log')
+        expect(content).to include('*.wasm')
+        expect(content).to include('/rubies')
+      end
+
+      it 'does not add duplicate entries' do
+        File.write('.gitignore', "*.wasm\n")
+        base_instance.send(:update_gitignore, ['*.wasm', '/rubies'])
+        content = File.read('.gitignore')
+        expect(content.scan(/^\*\.wasm$/).count).to eq(1)
+      end
+
+      it 'outputs message when entries are added' do
+        expect { base_instance.send(:update_gitignore, ['*.wasm']) }.to output(
+          /Added to .gitignore: \*\.wasm/
+        ).to_stdout
+      end
+
+      it 'outputs message when no entries are added' do
+        File.write('.gitignore', "*.wasm\n")
+        expect { base_instance.send(:update_gitignore, ['*.wasm']) }.to output(
+          /No new entries added to .gitignore/
+        ).to_stdout
+      end
+    end
+  end
+
+  describe '#run_command' do
+    context 'when command succeeds' do
+      it 'executes the command and outputs stdout' do
+        expect { base_instance.send(:run_command, 'echo "test output"') }.to output(
+          /test output/
+        ).to_stdout
+      end
+
+      it 'does not raise error' do
+        expect { base_instance.send(:run_command, 'echo "test"') }.not_to raise_error
+      end
+    end
+
+    context 'when command fails' do
+      it 'outputs error message and exits' do
+        expect { base_instance.send(:run_command, 'false') }.to output(
+          /Command failed: false/
+        ).to_stdout.and raise_error(SystemExit)
+      end
+    end
+  end
+end
diff --git a/spec/ruby_wasm_ui/cli/command/setup_spec.rb b/spec/ruby_wasm_ui/cli/command/setup_spec.rb
new file mode 100644
index 0000000..d3aa8cf
--- /dev/null
+++ b/spec/ruby_wasm_ui/cli/command/setup_spec.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe RubyWasmUi::Cli::Command::Setup do
+  let(:setup_instance) { described_class.new }
+
+  describe '.description' do
+    it 'returns the description' do
+      expect(described_class.description).to eq('Set up the project for ruby-wasm-ui')
+    end
+  end
+
+  describe '#run' do
+    before do
+      allow(setup_instance).to receive(:run_command)
+      allow(setup_instance).to receive(:update_gitignore)
+    end
+
+    it 'outputs setup message' do
+      expect { setup_instance.run([]) }.to output(
+        /Setting up ruby-wasm-ui project/
+      ).to_stdout
+    end
+
+    it 'executes rbwasm build command' do
+      expect(setup_instance).to receive(:run_command).with(
+        'bundle exec rbwasm build --ruby-version 3.4 -o ruby.wasm'
+      )
+      setup_instance.run([])
+    end
+
+    it 'updates .gitignore with required entries' do
+      expect(setup_instance).to receive(:update_gitignore).with(
+        ['*.wasm', '/rubies', '/build']
+      )
+      setup_instance.run([])
+    end
+
+    it 'outputs completion message' do
+      expect { setup_instance.run([]) }.to output(
+        /Setup completed successfully!/
+      ).to_stdout
+    end
+
+    it 'outputs progress messages' do
+      expect { setup_instance.run([]) }.to output(
+        /Building Ruby WASM/
+      ).to_stdout
+      expect { setup_instance.run([]) }.to output(
+        /Updating .gitignore/
+      ).to_stdout
+    end
+  end
+end
diff --git a/spec/ruby_wasm_ui/cli/command_spec.rb b/spec/ruby_wasm_ui/cli/command_spec.rb
new file mode 100644
index 0000000..8651e55
--- /dev/null
+++ b/spec/ruby_wasm_ui/cli/command_spec.rb
@@ -0,0 +1,64 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe RubyWasmUi::Cli::Command do
+  describe '.run' do
+    context 'when command is provided' do
+      context 'with valid command' do
+        let(:setup_instance) { instance_double(RubyWasmUi::Cli::Command::Setup) }
+
+        before do
+          allow(RubyWasmUi::Cli::Command::Setup).to receive(:new).and_return(setup_instance)
+          allow(setup_instance).to receive(:run)
+        end
+
+        it 'executes the setup command' do
+          expect(setup_instance).to receive(:run).with([])
+          described_class.run(['setup'])
+        end
+
+        it 'passes remaining arguments to the command' do
+          expect(setup_instance).to receive(:run).with(['arg1', 'arg2'])
+          described_class.run(['setup', 'arg1', 'arg2'])
+        end
+      end
+
+      context 'with invalid command' do
+        it 'prints error message and shows usage' do
+          expect { described_class.run(['unknown']) }.to output(
+            /Unknown command: unknown/
+          ).to_stdout.and raise_error(SystemExit)
+        end
+      end
+    end
+
+    context 'when no command is provided' do
+      it 'shows usage and exits' do
+        expect { described_class.run([]) }.to output(
+          /Usage: ruby-wasm-ui <command>/
+        ).to_stdout.and raise_error(SystemExit)
+      end
+    end
+  end
+
+  describe '.show_usage' do
+    it 'displays usage information' do
+      expect { described_class.show_usage }.to output(
+        /Usage: ruby-wasm-ui <command>/
+      ).to_stdout
+    end
+
+    it 'lists available commands' do
+      expect { described_class.show_usage }.to output(
+        /setup.*Set up the project for ruby-wasm-ui/
+      ).to_stdout
+    end
+  end
+
+  describe 'COMMANDS' do
+    it 'contains setup command' do
+      expect(described_class::COMMANDS).to include('setup' => RubyWasmUi::Cli::Command::Setup)
+    end
+  end
+end

From 6336c337729b70e8ab4a3f2dc1c50d210f6c066b Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 18:40:25 +0900
Subject: [PATCH 03/13] feat: Add dev command

---
 Gemfile.lock                              |  20 ++
 examples/Gemfile.lock                     |  30 +-
 lib/ruby_wasm_ui/cli/command.rb           |  10 +-
 lib/ruby_wasm_ui/cli/command/dev.rb       | 205 ++++++++++++++
 ruby_wasm_ui.gemspec                      |   3 +
 spec/ruby_wasm_ui/cli/command/dev_spec.rb | 325 ++++++++++++++++++++++
 spec/ruby_wasm_ui/cli/command_spec.rb     |  50 +++-
 7 files changed, 609 insertions(+), 34 deletions(-)
 create mode 100644 lib/ruby_wasm_ui/cli/command/dev.rb
 create mode 100644 spec/ruby_wasm_ui/cli/command/dev_spec.rb

diff --git a/Gemfile.lock b/Gemfile.lock
index 9d1fe2f..cdf5b22 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -3,6 +3,9 @@ PATH
   specs:
     ruby_wasm_ui (0.8.3)
       js (~> 2.7)
+      listen (~> 3.8)
+      puma (~> 6.0)
+      rack (~> 3.0)
       ruby_wasm (~> 2.7)
 
 GEM
@@ -11,20 +14,37 @@ GEM
     date (3.5.0)
     diff-lcs (1.6.2)
     erb (6.0.0)
+    ffi (1.17.2)
+    ffi (1.17.2-aarch64-linux-gnu)
+    ffi (1.17.2-aarch64-linux-musl)
+    ffi (1.17.2-arm64-darwin)
+    ffi (1.17.2-x86_64-darwin)
+    ffi (1.17.2-x86_64-linux-gnu)
+    ffi (1.17.2-x86_64-linux-musl)
     io-console (0.8.1)
     irb (1.15.3)
       pp (>= 0.6.0)
       rdoc (>= 4.0.0)
       reline (>= 0.4.2)
     js (2.7.2)
+    listen (3.9.0)
+      rb-fsevent (~> 0.10, >= 0.10.3)
+      rb-inotify (~> 0.9, >= 0.9.10)
     logger (1.7.0)
+    nio4r (2.7.5)
     pp (0.6.3)
       prettyprint
     prettyprint (0.2.0)
     psych (5.2.6)
       date
       stringio
+    puma (6.6.1)
+      nio4r (~> 2.0)
+    rack (3.2.4)
     rake (13.3.1)
+    rb-fsevent (0.11.2)
+    rb-inotify (0.11.1)
+      ffi (~> 1.0)
     rdoc (6.15.1)
       erb
       psych (>= 4.0.0)
diff --git a/examples/Gemfile.lock b/examples/Gemfile.lock
index 96a3b2b..c3cac2c 100644
--- a/examples/Gemfile.lock
+++ b/examples/Gemfile.lock
@@ -3,36 +3,34 @@ PATH
   specs:
     ruby_wasm_ui (0.8.3)
       js (~> 2.7)
+      listen (~> 3.8)
+      puma (~> 6.0)
+      rack (~> 3.0)
       ruby_wasm (~> 2.7)
 
 GEM
   remote: https://rubygems.org/
   specs:
+    ffi (1.17.2-arm64-darwin)
     js (2.7.2)
+    listen (3.9.0)
+      rb-fsevent (~> 0.10, >= 0.10.3)
+      rb-inotify (~> 0.9, >= 0.9.10)
     logger (1.7.0)
+    nio4r (2.7.5)
+    puma (6.6.1)
+      nio4r (~> 2.0)
+    rack (3.2.4)
+    rb-fsevent (0.11.2)
+    rb-inotify (0.11.1)
+      ffi (~> 1.0)
     ruby_wasm (2.7.2)
       logger
-    ruby_wasm (2.7.2-aarch64-linux)
-      logger
-    ruby_wasm (2.7.2-aarch64-linux-musl)
-      logger
     ruby_wasm (2.7.2-arm64-darwin)
       logger
-    ruby_wasm (2.7.2-x86_64-darwin)
-      logger
-    ruby_wasm (2.7.2-x86_64-linux)
-      logger
-    ruby_wasm (2.7.2-x86_64-linux-musl)
-      logger
 
 PLATFORMS
-  aarch64-linux
-  aarch64-linux-musl
   arm64-darwin
-  ruby
-  x86_64-darwin
-  x86_64-linux
-  x86_64-linux-musl
 
 DEPENDENCIES
   ruby_wasm_ui!
diff --git a/lib/ruby_wasm_ui/cli/command.rb b/lib/ruby_wasm_ui/cli/command.rb
index 3bf0463..dc0d1ba 100644
--- a/lib/ruby_wasm_ui/cli/command.rb
+++ b/lib/ruby_wasm_ui/cli/command.rb
@@ -1,18 +1,14 @@
 # frozen_string_literal: true
 
 require_relative "command/setup"
-# To add a new command (e.g., dev):
-# 1. Create lib/ruby_wasm_ui/cli/command/dev.rb inheriting from Command::Base
-# 2. Add require_relative "command/dev" above
-# 3. Add "dev" => Command::Dev to COMMANDS hash below
+require_relative "command/dev"
 
 module RubyWasmUi
   module Cli
     class Command
       COMMANDS = {
-        "setup" => Command::Setup
-        # Add new commands here, e.g.:
-        # "dev" => Command::Dev
+        "setup" => Command::Setup,
+        "dev" => Command::Dev
       }.freeze
 
       def self.run(argv)
diff --git a/lib/ruby_wasm_ui/cli/command/dev.rb b/lib/ruby_wasm_ui/cli/command/dev.rb
new file mode 100644
index 0000000..032df2b
--- /dev/null
+++ b/lib/ruby_wasm_ui/cli/command/dev.rb
@@ -0,0 +1,205 @@
+# frozen_string_literal: true
+
+require_relative "base"
+require "listen"
+require "rack"
+require "thread"
+
+module RubyWasmUi
+  module Cli
+    class Command
+      class Dev < Base
+        def self.description
+          "Start development server with file watching and auto-build"
+        end
+
+        def run(_argv)
+          log_info("Starting development server...")
+          puts ""
+
+          # Check if src directory exists
+          unless Dir.exist?("src")
+            log_error("src directory not found. Please run 'ruby-wasm-ui setup' first.")
+            exit 1
+          end
+
+          # Initial build
+          log_info("Performing initial build...")
+          build
+          log_success("✓ Initial build completed")
+          puts ""
+
+          # Start file watcher in a separate thread
+          @build_lock = Mutex.new
+          @build_queue = Queue.new
+          @listener = nil
+          @watcher_thread = nil
+
+          @watcher_thread = Thread.new do
+            start_file_watcher
+          end
+
+          # Register cleanup hook to ensure cleanup runs on exit
+          @cleanup_done = false
+          at_exit do
+            cleanup unless @cleanup_done
+          end
+
+          # Start development server
+          begin
+            start_server
+          ensure
+            cleanup
+          end
+        end
+
+        private
+
+        def cleanup
+          return if @cleanup_done
+          @cleanup_done = true
+          @listener&.stop
+          @watcher_thread&.kill
+        end
+
+        def build
+          command = "bundle exec rbwasm pack ruby.wasm --dir ./src::./src -o src.wasm"
+          log_info("Building: #{command}")
+
+          Open3.popen3(command) do |stdin, stdout, stderr, wait_thr|
+            stdin.close
+
+            stdout_thread = Thread.new do
+              stdout.each_line do |line|
+                print line
+                $stdout.flush
+              end
+            end
+
+            stderr_thread = Thread.new do
+              stderr.each_line do |line|
+                $stderr.print line
+                $stderr.flush
+              end
+            end
+
+            stdout_thread.join
+            stderr_thread.join
+
+            exit_status = wait_thr.value
+
+            unless exit_status.success?
+              log_error("Build failed")
+              return false
+            end
+
+            log_success("✓ Build completed")
+            true
+          end
+        end
+
+        def start_file_watcher
+          @listener = Listen.to("src") do |modified, added, removed|
+            files_changed = (modified + added + removed).reject do |file|
+              # Ignore temporary files and common build artifacts
+              file.end_with?(".swp", ".tmp", "~", ".wasm")
+            end
+
+            if files_changed.any?
+              log_info("Files changed: #{files_changed.join(', ')}")
+
+              # Debounce: add to queue
+              @build_queue << :build
+
+              # Process queue with debouncing
+              Thread.new do
+                sleep 0.5 # Debounce delay
+                begin
+                  if @build_queue.pop(true)
+                    @build_queue.clear
+                    @build_lock.synchronize do
+                      build
+                    end
+                  end
+                rescue ThreadError
+                  # Queue is empty, ignore
+                end
+              end
+            end
+          end
+
+          @listener.start
+        rescue => e
+          log_error("File watcher error: #{e.message}")
+        end
+
+        def start_server
+          port = 8080
+          log_info("Starting development server on http://localhost:#{port}")
+          log_info("Press Ctrl+C to stop")
+          puts ""
+
+          # Static file server application
+          static_app = lambda do |env|
+            path = env["PATH_INFO"]
+            file_path = File.join(Dir.pwd, path == "/" ? "index.html" : path)
+
+            if File.exist?(file_path) && File.file?(file_path)
+              content_type = Rack::Mime.mime_type(File.extname(file_path), "text/html")
+              [200, { "Content-Type" => content_type }, [File.read(file_path)]]
+            else
+              [404, { "Content-Type" => "text/plain" }, ["File not found: #{path}"]]
+            end
+          end
+
+          # CORS middleware
+          cors_middleware = lambda do |env|
+            if env["REQUEST_METHOD"] == "OPTIONS"
+              [
+                200,
+                {
+                  "Access-Control-Allow-Origin" => "*",
+                  "Access-Control-Allow-Methods" => "GET, POST, OPTIONS",
+                  "Access-Control-Allow-Headers" => "Content-Type"
+                },
+                []
+              ]
+            else
+              status, headers, body = static_app.call(env)
+              headers["Access-Control-Allow-Origin"] = "*"
+              headers["Access-Control-Allow-Methods"] = "GET, POST, OPTIONS"
+              headers["Access-Control-Allow-Headers"] = "Content-Type"
+              [status, headers, body]
+            end
+          end
+
+          # Create Rack application
+          app = Rack::Builder.new do
+            run cors_middleware
+          end
+
+          # Handle shutdown
+          trap("INT") do
+            log_info("\nShutting down server...")
+            cleanup
+            exit 0
+          end
+
+          # Use Puma handler (Rack 3.0 compatible)
+          begin
+            require "rack/handler/puma"
+            log_info("Using handler: puma")
+            Rack::Handler::Puma.run(app, Port: port, Host: "0.0.0.0")
+          rescue LoadError => e
+            log_error("Puma handler not available: #{e.message}")
+            log_error("Please ensure puma gem is installed: gem install puma")
+            exit 1
+          end
+        rescue => e
+          log_error("Server error: #{e.message}")
+          exit 1
+        end
+      end
+    end
+  end
+end
diff --git a/ruby_wasm_ui.gemspec b/ruby_wasm_ui.gemspec
index b7982c8..b1f7904 100644
--- a/ruby_wasm_ui.gemspec
+++ b/ruby_wasm_ui.gemspec
@@ -34,6 +34,9 @@ Gem::Specification.new do |spec|
   # Uncomment to register a new dependency of your gem
   spec.add_dependency "ruby_wasm", "~> 2.7"
   spec.add_dependency "js", "~> 2.7"
+  spec.add_dependency "listen", "~> 3.8"
+  spec.add_dependency "rack", "~> 3.0"
+  spec.add_dependency "puma", "~> 6.0"
 
   # For more information and examples about making a new gem, check out our
   # guide at: https://bundler.io/guides/creating_gem.html
diff --git a/spec/ruby_wasm_ui/cli/command/dev_spec.rb b/spec/ruby_wasm_ui/cli/command/dev_spec.rb
new file mode 100644
index 0000000..6fc5709
--- /dev/null
+++ b/spec/ruby_wasm_ui/cli/command/dev_spec.rb
@@ -0,0 +1,325 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require 'fileutils'
+require 'tmpdir'
+
+RSpec.describe RubyWasmUi::Cli::Command::Dev do
+  let(:dev_instance) { described_class.new }
+  let(:temp_dir) { Dir.mktmpdir }
+  let(:original_dir) { Dir.pwd }
+
+  around do |example|
+    Dir.chdir(temp_dir) do
+      example.run
+    end
+  ensure
+    Dir.chdir(original_dir)
+    FileUtils.rm_rf(temp_dir) if Dir.exist?(temp_dir)
+  end
+
+  describe '.description' do
+    it 'returns the description' do
+      expect(described_class.description).to eq('Start development server with file watching and auto-build')
+    end
+  end
+
+  describe '#run' do
+    let(:watcher_thread) { instance_double(Thread, kill: nil) }
+
+    before do
+      allow(dev_instance).to receive(:build).and_return(true)
+      allow(dev_instance).to receive(:start_file_watcher)
+      allow(dev_instance).to receive(:start_server)
+      allow(Thread).to receive(:new).and_return(watcher_thread)
+    end
+
+    context 'when src directory does not exist' do
+      it 'outputs error message and exits' do
+        expect { dev_instance.run([]) }.to output(
+          /src directory not found. Please run 'ruby-wasm-ui setup' first./
+        ).to_stdout.and raise_error(SystemExit)
+      end
+
+      it 'exits with status 1' do
+        expect { dev_instance.run([]) }.to raise_error(SystemExit) do |error|
+          expect(error.status).to eq(1)
+        end
+      end
+    end
+
+    context 'when src directory exists' do
+      before do
+        FileUtils.mkdir_p('src')
+      end
+
+      it 'outputs starting message' do
+        expect { dev_instance.run([]) }.to output(
+          /Starting development server/
+        ).to_stdout
+      end
+
+      it 'performs initial build' do
+        expect(dev_instance).to receive(:build).and_return(true)
+        dev_instance.run([])
+      end
+
+      it 'outputs initial build completion message' do
+        expect { dev_instance.run([]) }.to output(
+          /Initial build completed/
+        ).to_stdout
+      end
+
+      it 'starts file watcher' do
+        file_watcher_called = false
+        allow(dev_instance).to receive(:start_file_watcher) { file_watcher_called = true }
+        allow(dev_instance).to receive(:start_server) do
+          # Simulate blocking server
+          sleep 0.01
+        end
+        # Allow Thread.new to actually create threads so start_file_watcher gets called
+        allow(Thread).to receive(:new).and_call_original
+        Thread.new { sleep 0.02; Process.kill('INT', Process.pid) }
+        begin
+          dev_instance.run([])
+        rescue SystemExit
+          # Expected when server is killed
+        end
+        expect(file_watcher_called).to be true
+      end
+
+      it 'starts development server' do
+        allow(dev_instance).to receive(:start_file_watcher).and_return(nil)
+        expect(dev_instance).to receive(:start_server)
+        dev_instance.run([])
+      end
+
+      context 'when build fails' do
+        before do
+          allow(dev_instance).to receive(:build).and_return(false)
+        end
+
+        it 'still starts the server' do
+          expect(dev_instance).to receive(:start_server)
+          dev_instance.run([])
+        end
+      end
+    end
+  end
+
+  describe '#build' do
+    before do
+      FileUtils.mkdir_p('src')
+    end
+
+    context 'when command succeeds' do
+      let(:stdin) { double(close: nil) }
+      let(:stdout) { double(each_line: ['output'].to_enum) }
+      let(:stderr) { double(each_line: [].to_enum) }
+      let(:wait_thr) { double(value: double(success?: true)) }
+      let(:stdout_thread) { instance_double(Thread, join: nil) }
+      let(:stderr_thread) { instance_double(Thread, join: nil) }
+
+      before do
+        allow(Open3).to receive(:popen3).and_yield(stdin, stdout, stderr, wait_thr)
+        allow(Thread).to receive(:new).and_return(stdout_thread, stderr_thread)
+      end
+
+      it 'executes rbwasm pack command' do
+        expect(Open3).to receive(:popen3).with(
+          'bundle exec rbwasm pack ruby.wasm --dir ./src::./src -o src.wasm'
+        )
+        dev_instance.send(:build)
+      end
+
+      it 'outputs build message' do
+        expect { dev_instance.send(:build) }.to output(
+          /Building: bundle exec rbwasm pack/
+        ).to_stdout
+      end
+
+      it 'outputs success message' do
+        expect { dev_instance.send(:build) }.to output(
+          /Build completed/
+        ).to_stdout
+      end
+
+      it 'returns true' do
+        result = dev_instance.send(:build)
+        expect(result).to be true
+      end
+    end
+
+    context 'when command fails' do
+      let(:stdin) { double(close: nil) }
+      let(:stdout) { double(each_line: [].to_enum) }
+      let(:stderr) { double(each_line: ['error'].to_enum) }
+      let(:wait_thr) { double(value: double(success?: false, exitstatus: 1)) }
+      let(:stdout_thread) { instance_double(Thread, join: nil) }
+      let(:stderr_thread) { instance_double(Thread, join: nil) }
+
+      before do
+        allow(Open3).to receive(:popen3).and_yield(stdin, stdout, stderr, wait_thr)
+        allow(Thread).to receive(:new).and_return(stdout_thread, stderr_thread)
+      end
+
+      it 'outputs error message' do
+        expect { dev_instance.send(:build) }.to output(
+          /Build failed/
+        ).to_stdout
+      end
+
+      it 'returns false' do
+        result = dev_instance.send(:build)
+        expect(result).to be false
+      end
+    end
+  end
+
+  describe '#start_file_watcher' do
+    before do
+      FileUtils.mkdir_p('src')
+      @listener = instance_double(Listen::Listener, start: nil, stop: nil)
+      allow(Listen).to receive(:to).and_return(@listener)
+    end
+
+    it 'starts listening to src directory' do
+      expect(Listen).to receive(:to).with('src')
+      dev_instance.send(:start_file_watcher)
+    end
+
+    it 'starts the listener' do
+      expect(@listener).to receive(:start)
+      dev_instance.send(:start_file_watcher)
+    end
+
+    context 'when file changes occur' do
+      let(:callback_container) { {} }
+
+      before do
+        allow(Listen).to receive(:to) do |_dir, &block|
+          callback_container[:callback] = block
+          @listener
+        end
+        dev_instance.instance_variable_set(:@build_lock, Mutex.new)
+        dev_instance.instance_variable_set(:@build_queue, Queue.new)
+        allow(dev_instance).to receive(:build)
+        allow(dev_instance).to receive(:log_info)
+      end
+
+      it 'triggers rebuild on file change' do
+        dev_instance.send(:start_file_watcher)
+        callback = callback_container[:callback]
+        expect(callback).not_to be_nil
+        
+        # Allow Thread.new to create actual threads for the debounce logic
+        allow(Thread).to receive(:new).and_call_original
+        
+        callback.call(['src/app.rb'], [], [])
+        sleep 0.6 # Wait for debounce
+        expect(dev_instance).to have_received(:build)
+      end
+
+      it 'ignores temporary files' do
+        dev_instance.send(:start_file_watcher)
+        callback = callback_container[:callback]
+        expect(callback).not_to be_nil
+        
+        # Allow Thread.new to create actual threads for the debounce logic
+        allow(Thread).to receive(:new).and_call_original
+        
+        callback.call(['src/app.rb.swp'], [], [])
+        sleep 0.6
+        expect(dev_instance).not_to have_received(:build)
+      end
+    end
+
+    context 'when listener raises an error' do
+      before do
+        allow(Listen).to receive(:to).and_raise(StandardError.new('Listener error'))
+      end
+
+      it 'outputs error message' do
+        expect { dev_instance.send(:start_file_watcher) }.to output(
+          /File watcher error: Listener error/
+        ).to_stdout
+      end
+    end
+  end
+
+  describe '#start_server' do
+    let(:puma_handler_class) do
+      Class.new do
+        def self.run(app, options = {})
+          # Blocking call - will be mocked
+        end
+      end
+    end
+
+    before do
+      FileUtils.mkdir_p('src')
+      stub_const('Rack::Handler::Puma', puma_handler_class)
+      allow(Kernel).to receive(:require).with('rack/handler/puma')
+    end
+
+    it 'outputs server start message' do
+      allow(Rack::Handler::Puma).to receive(:run)
+      expect { dev_instance.send(:start_server) }.to output(
+        /Starting development server on http:\/\/localhost:8080/
+      ).to_stdout
+    end
+
+    it 'outputs instructions message' do
+      allow(Rack::Handler::Puma).to receive(:run)
+      expect { dev_instance.send(:start_server) }.to output(
+        /Press Ctrl+C to stop/
+      ).to_stdout
+    end
+
+    it 'starts Puma server' do
+      expect(Rack::Handler::Puma).to receive(:run).with(
+        anything,
+        Port: 8080,
+        Host: '0.0.0.0'
+      )
+      dev_instance.send(:start_server)
+    end
+
+    it 'outputs handler info message' do
+      allow(Rack::Handler::Puma).to receive(:run)
+      expect { dev_instance.send(:start_server) }.to output(
+        /Using handler: puma/
+      ).to_stdout
+    end
+
+    context 'when Puma handler is not available' do
+      before do
+        allow(Kernel).to receive(:require).with('rack/handler/puma').and_raise(LoadError.new('cannot load such file'))
+      end
+
+      it 'outputs error message' do
+        expect { dev_instance.send(:start_server) }.to output(
+          /Puma handler not available/
+        ).to_stdout.and raise_error(SystemExit)
+      end
+
+      it 'exits with status 1' do
+        expect { dev_instance.send(:start_server) }.to raise_error(SystemExit) do |error|
+          expect(error.status).to eq(1)
+        end
+      end
+    end
+
+    context 'when server raises an error' do
+      before do
+        allow(Rack::Handler::Puma).to receive(:run).and_raise(StandardError.new('Server error'))
+      end
+
+      it 'outputs error message and exits' do
+        expect { dev_instance.send(:start_server) }.to output(
+          /Server error: Server error/
+        ).to_stdout.and raise_error(SystemExit)
+      end
+    end
+  end
+end
diff --git a/spec/ruby_wasm_ui/cli/command_spec.rb b/spec/ruby_wasm_ui/cli/command_spec.rb
index 8651e55..a09d8d0 100644
--- a/spec/ruby_wasm_ui/cli/command_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command_spec.rb
@@ -6,21 +6,42 @@
   describe '.run' do
     context 'when command is provided' do
       context 'with valid command' do
-        let(:setup_instance) { instance_double(RubyWasmUi::Cli::Command::Setup) }
+        context 'setup command' do
+          let(:setup_instance) { instance_double(RubyWasmUi::Cli::Command::Setup) }
 
-        before do
-          allow(RubyWasmUi::Cli::Command::Setup).to receive(:new).and_return(setup_instance)
-          allow(setup_instance).to receive(:run)
-        end
+          before do
+            allow(RubyWasmUi::Cli::Command::Setup).to receive(:new).and_return(setup_instance)
+            allow(setup_instance).to receive(:run)
+          end
+
+          it 'executes the setup command' do
+            expect(setup_instance).to receive(:run).with([])
+            described_class.run(['setup'])
+          end
 
-        it 'executes the setup command' do
-          expect(setup_instance).to receive(:run).with([])
-          described_class.run(['setup'])
+          it 'passes remaining arguments to the command' do
+            expect(setup_instance).to receive(:run).with(['arg1', 'arg2'])
+            described_class.run(['setup', 'arg1', 'arg2'])
+          end
         end
 
-        it 'passes remaining arguments to the command' do
-          expect(setup_instance).to receive(:run).with(['arg1', 'arg2'])
-          described_class.run(['setup', 'arg1', 'arg2'])
+        context 'dev command' do
+          let(:dev_instance) { instance_double(RubyWasmUi::Cli::Command::Dev) }
+
+          before do
+            allow(RubyWasmUi::Cli::Command::Dev).to receive(:new).and_return(dev_instance)
+            allow(dev_instance).to receive(:run)
+          end
+
+          it 'executes the dev command' do
+            expect(dev_instance).to receive(:run).with([])
+            described_class.run(['dev'])
+          end
+
+          it 'passes remaining arguments to the command' do
+            expect(dev_instance).to receive(:run).with(['arg1', 'arg2'])
+            described_class.run(['dev', 'arg1', 'arg2'])
+          end
         end
       end
 
@@ -53,6 +74,9 @@
       expect { described_class.show_usage }.to output(
         /setup.*Set up the project for ruby-wasm-ui/
       ).to_stdout
+      expect { described_class.show_usage }.to output(
+        /dev.*Start development server with file watching and auto-build/
+      ).to_stdout
     end
   end
 
@@ -60,5 +84,9 @@
     it 'contains setup command' do
       expect(described_class::COMMANDS).to include('setup' => RubyWasmUi::Cli::Command::Setup)
     end
+
+    it 'contains dev command' do
+      expect(described_class::COMMANDS).to include('dev' => RubyWasmUi::Cli::Command::Dev)
+    end
   end
 end

From 82f18877dac6d63647809b2ed5fc5e9738aecfea Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 18:56:50 +0900
Subject: [PATCH 04/13] update: Set ruby version for user local

---
 lib/ruby_wasm_ui/cli/command/setup.rb       | 15 +++++-
 spec/ruby_wasm_ui/cli/command/setup_spec.rb | 55 ++++++++++++++++++++-
 2 files changed, 67 insertions(+), 3 deletions(-)

diff --git a/lib/ruby_wasm_ui/cli/command/setup.rb b/lib/ruby_wasm_ui/cli/command/setup.rb
index 0ffb738..3eae030 100644
--- a/lib/ruby_wasm_ui/cli/command/setup.rb
+++ b/lib/ruby_wasm_ui/cli/command/setup.rb
@@ -14,10 +14,21 @@ def run(_argv)
           log_info("Setting up ruby-wasm-ui project...")
           puts ""
 
+          # Check Ruby version
+          ruby_version = RUBY_VERSION.split('.').map(&:to_i)
+          major, minor = ruby_version[0], ruby_version[1]
+
+          if major < 3 || (major == 3 && minor < 2)
+            log_error("Ruby WASM requires Ruby 3.2 or higher. Current version: #{RUBY_VERSION}")
+            exit 1
+          end
+
+          ruby_version_str = "#{major}.#{minor}"
+
           # Build Ruby WASM
           log_info("Step 1/2: Building Ruby WASM...")
-          log_info("Running: bundle exec rbwasm build --ruby-version 3.4 -o ruby.wasm")
-          run_command("bundle exec rbwasm build --ruby-version 3.4 -o ruby.wasm")
+          log_info("Running: bundle exec rbwasm build --ruby-version #{ruby_version_str} -o ruby.wasm")
+          run_command("bundle exec rbwasm build --ruby-version #{ruby_version_str} -o ruby.wasm")
           log_success("✓ Ruby WASM build completed")
 
           # Update .gitignore
diff --git a/spec/ruby_wasm_ui/cli/command/setup_spec.rb b/spec/ruby_wasm_ui/cli/command/setup_spec.rb
index d3aa8cf..ac409b7 100644
--- a/spec/ruby_wasm_ui/cli/command/setup_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/setup_spec.rb
@@ -24,8 +24,9 @@
     end
 
     it 'executes rbwasm build command' do
+      ruby_version = RUBY_VERSION.split('.')[0..1].join('.')
       expect(setup_instance).to receive(:run_command).with(
-        'bundle exec rbwasm build --ruby-version 3.4 -o ruby.wasm'
+        "bundle exec rbwasm build --ruby-version #{ruby_version} -o ruby.wasm"
       )
       setup_instance.run([])
     end
@@ -51,5 +52,57 @@
         /Updating .gitignore/
       ).to_stdout
     end
+
+    context 'when Ruby version is less than 3.2' do
+      before do
+        allow(Kernel).to receive(:exit)
+      end
+
+      context 'when Ruby version is 3.1' do
+        before do
+          stub_const('RUBY_VERSION', '3.1.5')
+        end
+
+        it 'outputs error message and exits' do
+          expect { setup_instance.run([]) }.to output(
+            /\[ERROR\] Ruby WASM requires Ruby 3.2 or higher. Current version: 3.1.5/
+          ).to_stdout
+          expect(Kernel).to have_received(:exit).with(1)
+        end
+
+        it 'does not execute rbwasm build command' do
+          expect(setup_instance).not_to receive(:run_command)
+          setup_instance.run([])
+        end
+      end
+
+      context 'when Ruby version is 2.7' do
+        before do
+          stub_const('RUBY_VERSION', '2.7.8')
+        end
+
+        it 'outputs error message and exits' do
+          expect { setup_instance.run([]) }.to output(
+            /\[ERROR\] Ruby WASM requires Ruby 3.2 or higher. Current version: 2.7.8/
+          ).to_stdout
+          expect(Kernel).to have_received(:exit).with(1)
+        end
+      end
+    end
+
+    context 'when Ruby version is 3.2' do
+      before do
+        stub_const('RUBY_VERSION', '3.2.0')
+        allow(setup_instance).to receive(:run_command)
+        allow(setup_instance).to receive(:update_gitignore)
+      end
+
+      it 'executes rbwasm build command with correct version' do
+        expect(setup_instance).to receive(:run_command).with(
+          'bundle exec rbwasm build --ruby-version 3.2 -o ruby.wasm'
+        )
+        setup_instance.run([])
+      end
+    end
   end
 end

From 125d4c069fc9ce48a5b509be0debbc520d3e5db9 Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 19:12:58 +0900
Subject: [PATCH 05/13] feat: Exclude unnecessary gems for build

---
 lib/ruby_wasm_ui/cli/command/setup.rb       | 55 +++++++++++-
 spec/ruby_wasm_ui/cli/command/setup_spec.rb | 97 +++++++++++++++++++--
 2 files changed, 139 insertions(+), 13 deletions(-)

diff --git a/lib/ruby_wasm_ui/cli/command/setup.rb b/lib/ruby_wasm_ui/cli/command/setup.rb
index 3eae030..435097f 100644
--- a/lib/ruby_wasm_ui/cli/command/setup.rb
+++ b/lib/ruby_wasm_ui/cli/command/setup.rb
@@ -1,5 +1,8 @@
 # frozen_string_literal: true
 
+require "bundler/setup"
+require "ruby_wasm"
+require "ruby_wasm/cli"
 require_relative "base"
 
 module RubyWasmUi
@@ -25,20 +28,64 @@ def run(_argv)
 
           ruby_version_str = "#{major}.#{minor}"
 
+          # Configure excluded gems for WASM build
+          log_info("Step 1/3: Configuring excluded gems...")
+          configure_excluded_gems
+          log_success("✓ Excluded gems configured")
+
           # Build Ruby WASM
-          log_info("Step 1/2: Building Ruby WASM...")
-          log_info("Running: bundle exec rbwasm build --ruby-version #{ruby_version_str} -o ruby.wasm")
-          run_command("bundle exec rbwasm build --ruby-version #{ruby_version_str} -o ruby.wasm")
+          puts ""
+          log_info("Step 2/3: Building Ruby WASM...")
+          log_info("Running: rbwasm build --ruby-version #{ruby_version_str} -o ruby.wasm")
+          build_ruby_wasm(ruby_version_str)
           log_success("✓ Ruby WASM build completed")
 
           # Update .gitignore
           puts ""
-          log_info("Step 2/2: Updating .gitignore...")
+          log_info("Step 3/3: Updating .gitignore...")
           update_gitignore(["*.wasm", "/rubies", "/build"])
 
           puts ""
           log_success("Setup completed successfully!")
         end
+
+        private
+
+        def configure_excluded_gems
+          # Get all gems from Bundler definition including all dependencies
+          definition = Bundler.definition
+          resolved = definition.resolve
+
+          # Get all resolved specs (including transitive dependencies)
+          all_specs = resolved.materialize(definition.requested_dependencies)
+          gem_names = all_specs.map(&:name).uniq
+
+          # Always exclude gems that cause WASM build errors
+          # These gems have native extensions that don't work in WASM environment
+          always_excluded = %w[nio4r puma rack listen ffi]
+
+          # Exclude gems that cause build errors or are unnecessary for WASM
+          # Keep essential gems like 'js' for WASM
+          excluded_gems = gem_names.select do |gem_name|
+            # Exclude gems that cause WASM build errors
+            always_excluded.include?(gem_name) ||
+              # Exclude development/test gems
+              gem_name.start_with?("rspec", "rubocop", "rake")
+          end
+
+          # Always add always_excluded gems to ensure they're excluded even if not in dependencies
+          excluded_gems.concat(always_excluded)
+          excluded_gems.uniq!
+
+          # Add to EXCLUDED_GEMS
+          RubyWasm::Packager::EXCLUDED_GEMS.concat(excluded_gems)
+        end
+
+        def build_ruby_wasm(ruby_version_str)
+          command = ["build", "--ruby-version", ruby_version_str, "-o", "ruby.wasm"]
+          cli = RubyWasm::CLI.new(stdout: $stdout, stderr: $stderr)
+          cli.run(command)
+        end
       end
     end
   end
diff --git a/spec/ruby_wasm_ui/cli/command/setup_spec.rb b/spec/ruby_wasm_ui/cli/command/setup_spec.rb
index ac409b7..635792f 100644
--- a/spec/ruby_wasm_ui/cli/command/setup_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/setup_spec.rb
@@ -13,7 +13,8 @@
 
   describe '#run' do
     before do
-      allow(setup_instance).to receive(:run_command)
+      allow(setup_instance).to receive(:configure_excluded_gems)
+      allow(setup_instance).to receive(:build_ruby_wasm)
       allow(setup_instance).to receive(:update_gitignore)
     end
 
@@ -23,11 +24,14 @@
       ).to_stdout
     end
 
+    it 'configures excluded gems' do
+      expect(setup_instance).to receive(:configure_excluded_gems)
+      setup_instance.run([])
+    end
+
     it 'executes rbwasm build command' do
       ruby_version = RUBY_VERSION.split('.')[0..1].join('.')
-      expect(setup_instance).to receive(:run_command).with(
-        "bundle exec rbwasm build --ruby-version #{ruby_version} -o ruby.wasm"
-      )
+      expect(setup_instance).to receive(:build_ruby_wasm).with(ruby_version)
       setup_instance.run([])
     end
 
@@ -45,6 +49,9 @@
     end
 
     it 'outputs progress messages' do
+      expect { setup_instance.run([]) }.to output(
+        /Configuring excluded gems/
+      ).to_stdout
       expect { setup_instance.run([]) }.to output(
         /Building Ruby WASM/
       ).to_stdout
@@ -71,7 +78,8 @@
         end
 
         it 'does not execute rbwasm build command' do
-          expect(setup_instance).not_to receive(:run_command)
+          expect(setup_instance).not_to receive(:build_ruby_wasm)
+          expect(setup_instance).not_to receive(:configure_excluded_gems)
           setup_instance.run([])
         end
       end
@@ -93,16 +101,87 @@
     context 'when Ruby version is 3.2' do
       before do
         stub_const('RUBY_VERSION', '3.2.0')
-        allow(setup_instance).to receive(:run_command)
+        allow(setup_instance).to receive(:configure_excluded_gems)
+        allow(setup_instance).to receive(:build_ruby_wasm)
         allow(setup_instance).to receive(:update_gitignore)
       end
 
       it 'executes rbwasm build command with correct version' do
-        expect(setup_instance).to receive(:run_command).with(
-          'bundle exec rbwasm build --ruby-version 3.2 -o ruby.wasm'
-        )
+        expect(setup_instance).to receive(:build_ruby_wasm).with('3.2')
         setup_instance.run([])
       end
     end
   end
+
+  describe '#configure_excluded_gems' do
+    before do
+      # Clear EXCLUDED_GEMS before each test
+      RubyWasm::Packager::EXCLUDED_GEMS.clear if defined?(RubyWasm::Packager::EXCLUDED_GEMS)
+    end
+
+    it 'excludes rack, puma, nio4r, listen, and ffi gems' do
+      allow(Bundler).to receive(:definition).and_return(
+        double(
+          resolve: double(
+            materialize: [
+              double(name: 'rack'),
+              double(name: 'puma'),
+              double(name: 'nio4r'),
+              double(name: 'listen'),
+              double(name: 'ffi'),
+              double(name: 'js'),
+              double(name: 'ruby_wasm')
+            ]
+          ),
+          requested_dependencies: []
+        )
+      )
+
+      setup_instance.send(:configure_excluded_gems)
+
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).to include('rack', 'puma', 'nio4r', 'listen', 'ffi')
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).not_to include('js', 'ruby_wasm')
+    end
+
+    it 'always excludes nio4r, puma, rack, listen, and ffi even if not in dependencies' do
+      allow(Bundler).to receive(:definition).and_return(
+        double(
+          resolve: double(
+            materialize: [
+              double(name: 'js'),
+              double(name: 'ruby_wasm')
+            ]
+          ),
+          requested_dependencies: []
+        )
+      )
+
+      setup_instance.send(:configure_excluded_gems)
+
+      # Always excluded gems should be in the list even if not in dependencies
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).to include('nio4r', 'puma', 'rack', 'listen', 'ffi')
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).not_to include('js', 'ruby_wasm')
+    end
+
+    it 'excludes development/test gems' do
+      allow(Bundler).to receive(:definition).and_return(
+        double(
+          resolve: double(
+            materialize: [
+              double(name: 'rspec'),
+              double(name: 'rubocop'),
+              double(name: 'rake'),
+              double(name: 'js')
+            ]
+          ),
+          requested_dependencies: []
+        )
+      )
+
+      setup_instance.send(:configure_excluded_gems)
+
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).to include('rspec', 'rubocop', 'rake')
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).not_to include('js')
+    end
+  end
 end

From c63c6e330c46087a2e14fd15d53ba7158b099126 Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 20:04:56 +0900
Subject: [PATCH 06/13] feat: Create initial file with setup command

---
 examples/src/index.html                     | 21 +++++
 examples/src/index.rb                       | 26 ++++++
 lib/ruby_wasm_ui/cli/command/setup.rb       | 87 ++++++++++++++++++++-
 spec/ruby_wasm_ui/cli/command/setup_spec.rb | 76 ++++++++++++++++++
 4 files changed, 209 insertions(+), 1 deletion(-)
 create mode 100644 examples/src/index.html
 create mode 100644 examples/src/index.rb

diff --git a/examples/src/index.html b/examples/src/index.html
new file mode 100644
index 0000000..d671269
--- /dev/null
+++ b/examples/src/index.html
@@ -0,0 +1,21 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <title>My App</title>
+    <script type="module">
+      import { DefaultRubyVM } from "https://cdn.jsdelivr.net/npm/@ruby/wasm-wasi@2.7.2/dist/browser/+esm";
+      const response = await fetch("../src.wasm");
+      const module = await WebAssembly.compileStreaming(response);
+      const { vm } = await DefaultRubyVM(module);
+      vm.evalAsync(`
+        require "ruby_wasm_ui"
+        require_relative './src/index.rb'
+      `);
+    </script>
+  </head>
+  <body>
+    <h1>My App</h1>
+    <div id="app"></div>
+  </body>
+</html>
diff --git a/examples/src/index.rb b/examples/src/index.rb
new file mode 100644
index 0000000..4e540bb
--- /dev/null
+++ b/examples/src/index.rb
@@ -0,0 +1,26 @@
+# Simple Hello World component
+HelloComponent = RubyWasmUi.define_component(
+  state: ->(props) {
+    { message: props[:message] || "Hello, Ruby WASM UI!" }
+  },
+  template: ->() {
+    RubyWasmUi::Template::Parser.parse_and_eval(<<~HTML, binding)
+      <div>
+        <h2>{state[:message]}</h2>
+        <button on="{ click: -> { update_message } }">
+          Click me!
+        </button>
+      </div>
+    HTML
+  },
+  methods: {
+    update_message: ->() {
+      update_state(message: "You clicked the button!")
+    }
+  }
+)
+
+# Create and mount the app
+app = RubyWasmUi::App.create(HelloComponent, message: "Hello, Ruby WASM UI!")
+app_element = JS.global[:document].getElementById("app")
+app.mount(app_element)
diff --git a/lib/ruby_wasm_ui/cli/command/setup.rb b/lib/ruby_wasm_ui/cli/command/setup.rb
index 435097f..49c76b8 100644
--- a/lib/ruby_wasm_ui/cli/command/setup.rb
+++ b/lib/ruby_wasm_ui/cli/command/setup.rb
@@ -42,8 +42,14 @@ def run(_argv)
 
           # Update .gitignore
           puts ""
-          log_info("Step 3/3: Updating .gitignore...")
+          log_info("Step 3/4: Updating .gitignore...")
           update_gitignore(["*.wasm", "/rubies", "/build"])
+          log_success("✓ .gitignore updated")
+
+          # Create initial files
+          puts ""
+          log_info("Step 4/4: Creating initial files...")
+          create_initial_files
 
           puts ""
           log_success("Setup completed successfully!")
@@ -86,6 +92,85 @@ def build_ruby_wasm(ruby_version_str)
           cli = RubyWasm::CLI.new(stdout: $stdout, stderr: $stderr)
           cli.run(command)
         end
+
+        def create_initial_files
+          # Skip if src directory exists
+          if Dir.exist?("src")
+            log_info("src directory already exists, skipping initial file creation")
+            return
+          end
+
+          # Skip if files already exist
+          if File.exist?("src/index.html")
+            log_info("src/index.html already exists, skipping initial file creation")
+            return
+          end
+
+          if File.exist?("src/index.rb")
+            log_info("src/index.rb already exists, skipping initial file creation")
+            return
+          end
+
+          # Create src directory
+          Dir.mkdir("src")
+
+          # Create index.html
+          File.write("src/index.html", <<~HTML)
+            <!DOCTYPE html>
+            <html lang="en">
+              <head>
+                <meta charset="UTF-8" />
+                <title>My App</title>
+                <script type="module">
+                  import { DefaultRubyVM } from "https://cdn.jsdelivr.net/npm/@ruby/wasm-wasi@2.7.2/dist/browser/+esm";
+                  const response = await fetch("../src.wasm");
+                  const module = await WebAssembly.compileStreaming(response);
+                  const { vm } = await DefaultRubyVM(module);
+                  vm.evalAsync(`
+                    require "ruby_wasm_ui"
+                    require_relative './src/index.rb'
+                  `);
+                </script>
+              </head>
+              <body>
+                <h1>My App</h1>
+                <div id="app"></div>
+              </body>
+            </html>
+          HTML
+
+          # Create index.rb
+          File.write("src/index.rb", <<~RUBY)
+            # Simple Hello World component
+            HelloComponent = RubyWasmUi.define_component(
+              state: ->(props) {
+                { message: props[:message] || "Hello, Ruby WASM UI!" }
+              },
+              template: ->() {
+                RubyWasmUi::Template::Parser.parse_and_eval(<<~HTML, binding)
+                  <div>
+                    <h2>{state[:message]}</h2>
+                    <button on="{ click: -> { update_message } }">
+                      Click me!
+                    </button>
+                  </div>
+                HTML
+              },
+              methods: {
+                update_message: ->() {
+                  update_state(message: "You clicked the button!")
+                }
+              }
+            )
+
+            # Create and mount the app
+            app = RubyWasmUi::App.create(HelloComponent, message: "Hello, Ruby WASM UI!")
+            app_element = JS.global[:document].getElementById("app")
+            app.mount(app_element)
+          RUBY
+
+          log_success("✓ Initial files created: src/index.html, src/index.rb")
+        end
       end
     end
   end
diff --git a/spec/ruby_wasm_ui/cli/command/setup_spec.rb b/spec/ruby_wasm_ui/cli/command/setup_spec.rb
index 635792f..75bdfe3 100644
--- a/spec/ruby_wasm_ui/cli/command/setup_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/setup_spec.rb
@@ -16,6 +16,7 @@
       allow(setup_instance).to receive(:configure_excluded_gems)
       allow(setup_instance).to receive(:build_ruby_wasm)
       allow(setup_instance).to receive(:update_gitignore)
+      allow(setup_instance).to receive(:create_initial_files)
     end
 
     it 'outputs setup message' do
@@ -58,6 +59,14 @@
       expect { setup_instance.run([]) }.to output(
         /Updating .gitignore/
       ).to_stdout
+      expect { setup_instance.run([]) }.to output(
+        /Creating initial files/
+      ).to_stdout
+    end
+
+    it 'creates initial files' do
+      expect(setup_instance).to receive(:create_initial_files)
+      setup_instance.run([])
     end
 
     context 'when Ruby version is less than 3.2' do
@@ -104,6 +113,7 @@
         allow(setup_instance).to receive(:configure_excluded_gems)
         allow(setup_instance).to receive(:build_ruby_wasm)
         allow(setup_instance).to receive(:update_gitignore)
+        allow(setup_instance).to receive(:create_initial_files)
       end
 
       it 'executes rbwasm build command with correct version' do
@@ -184,4 +194,70 @@
       expect(RubyWasm::Packager::EXCLUDED_GEMS).not_to include('js')
     end
   end
+
+  describe '#create_initial_files' do
+    let(:temp_dir) { Dir.mktmpdir }
+    let(:src_dir) { File.join(temp_dir, 'src') }
+
+    before do
+      allow(Dir).to receive(:pwd).and_return(temp_dir)
+      allow(Dir).to receive(:exist?).and_call_original
+      allow(File).to receive(:exist?).and_call_original
+      allow(File).to receive(:write).and_call_original
+      allow(Dir).to receive(:mkdir).and_call_original
+    end
+
+    after do
+      FileUtils.rm_rf(temp_dir) if Dir.exist?(temp_dir)
+    end
+
+    context 'when src directory does not exist' do
+      it 'creates src directory and initial files' do
+        expect(Dir).to receive(:exist?).with('src').and_return(false)
+        expect(File).to receive(:exist?).with('src/index.html').and_return(false)
+        expect(File).to receive(:exist?).with('src/index.rb').and_return(false)
+        expect(Dir).to receive(:mkdir).with('src')
+        expect(File).to receive(:write).with('src/index.html', anything)
+        expect(File).to receive(:write).with('src/index.rb', anything)
+
+        setup_instance.send(:create_initial_files)
+      end
+    end
+
+    context 'when src directory already exists' do
+      it 'skips file creation' do
+        expect(Dir).to receive(:exist?).with('src').and_return(true)
+        expect(File).not_to receive(:write)
+
+        expect { setup_instance.send(:create_initial_files) }.to output(
+          /src directory already exists, skipping initial file creation/
+        ).to_stdout
+      end
+    end
+
+    context 'when src/index.html already exists' do
+      it 'skips file creation' do
+        expect(Dir).to receive(:exist?).with('src').and_return(false)
+        expect(File).to receive(:exist?).with('src/index.html').and_return(true)
+        expect(File).not_to receive(:write)
+
+        expect { setup_instance.send(:create_initial_files) }.to output(
+          /src\/index.html already exists, skipping initial file creation/
+        ).to_stdout
+      end
+    end
+
+    context 'when src/index.rb already exists' do
+      it 'skips file creation' do
+        expect(Dir).to receive(:exist?).with('src').and_return(false)
+        expect(File).to receive(:exist?).with('src/index.html').and_return(false)
+        expect(File).to receive(:exist?).with('src/index.rb').and_return(true)
+        expect(File).not_to receive(:write)
+
+        expect { setup_instance.send(:create_initial_files) }.to output(
+          /src\/index.rb already exists, skipping initial file creation/
+        ).to_stdout
+      end
+    end
+  end
 end

From bfa6e2c394fd0348b3d637438c1db657954215df Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 20:16:27 +0900
Subject: [PATCH 07/13] feat: Open index.html with dev command

---
 lib/ruby_wasm_ui/cli/command/dev.rb       | 30 +++++++-
 spec/ruby_wasm_ui/cli/command/dev_spec.rb | 84 +++++++++++++++++++++++
 2 files changed, 113 insertions(+), 1 deletion(-)

diff --git a/lib/ruby_wasm_ui/cli/command/dev.rb b/lib/ruby_wasm_ui/cli/command/dev.rb
index 032df2b..81be1ce 100644
--- a/lib/ruby_wasm_ui/cli/command/dev.rb
+++ b/lib/ruby_wasm_ui/cli/command/dev.rb
@@ -4,6 +4,7 @@
 require "listen"
 require "rack"
 require "thread"
+require "rbconfig"
 
 module RubyWasmUi
   module Cli
@@ -55,6 +56,22 @@ def run(_argv)
 
         private
 
+        def open_browser(url)
+          case RbConfig::CONFIG["host_os"]
+          when /darwin/
+            system("open", url)
+          when /linux/
+            system("xdg-open", url)
+          when /mswin|mingw|cygwin/
+            system("start", url)
+          else
+            log_info("Please open #{url} in your browser")
+          end
+        rescue => e
+          log_info("Could not open browser automatically: #{e.message}")
+          log_info("Please open #{url} in your browser")
+        end
+
         def cleanup
           return if @cleanup_done
           @cleanup_done = true
@@ -142,7 +159,11 @@ def start_server
           # Static file server application
           static_app = lambda do |env|
             path = env["PATH_INFO"]
-            file_path = File.join(Dir.pwd, path == "/" ? "index.html" : path)
+            if path == "/"
+              file_path = File.join(Dir.pwd, "src", "index.html")
+            else
+              file_path = File.join(Dir.pwd, path)
+            end
 
             if File.exist?(file_path) && File.file?(file_path)
               content_type = Rack::Mime.mime_type(File.extname(file_path), "text/html")
@@ -189,6 +210,13 @@ def start_server
           begin
             require "rack/handler/puma"
             log_info("Using handler: puma")
+
+            # Open browser after a short delay to ensure server is ready
+            Thread.new do
+              sleep 1
+              open_browser("http://localhost:#{port}/src/index.html")
+            end
+
             Rack::Handler::Puma.run(app, Port: port, Host: "0.0.0.0")
           rescue LoadError => e
             log_error("Puma handler not available: #{e.message}")
diff --git a/spec/ruby_wasm_ui/cli/command/dev_spec.rb b/spec/ruby_wasm_ui/cli/command/dev_spec.rb
index 6fc5709..378106c 100644
--- a/spec/ruby_wasm_ui/cli/command/dev_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/dev_spec.rb
@@ -292,6 +292,27 @@ def self.run(app, options = {})
       ).to_stdout
     end
 
+    it 'opens browser after server starts' do
+      allow(Rack::Handler::Puma).to receive(:run)
+      browser_thread_called = false
+      
+      allow(Thread).to receive(:new) do |&block|
+        if block
+          browser_thread_called = true
+          # Execute block immediately for testing (without sleep)
+          allow(Kernel).to receive(:sleep)
+          block.call
+        end
+        instance_double(Thread)
+      end
+      
+      expect(dev_instance).to receive(:open_browser).with('http://localhost:8080/src/index.html')
+      
+      dev_instance.send(:start_server)
+      
+      expect(browser_thread_called).to be true
+    end
+
     context 'when Puma handler is not available' do
       before do
         allow(Kernel).to receive(:require).with('rack/handler/puma').and_raise(LoadError.new('cannot load such file'))
@@ -322,4 +343,67 @@ def self.run(app, options = {})
       end
     end
   end
+
+  describe '#open_browser' do
+    before do
+      FileUtils.mkdir_p('src')
+    end
+
+    context 'on macOS' do
+      before do
+        allow(RbConfig::CONFIG).to receive(:[]).with('host_os').and_return('darwin')
+      end
+
+      it 'calls open command' do
+        expect(dev_instance).to receive(:system).with('open', 'http://localhost:8080/src/index.html')
+        dev_instance.send(:open_browser, 'http://localhost:8080/src/index.html')
+      end
+
+      context 'when system call fails' do
+        before do
+          allow(dev_instance).to receive(:system).and_raise(StandardError.new('Command failed'))
+        end
+
+        it 'outputs fallback message' do
+          expect { dev_instance.send(:open_browser, 'http://localhost:8080/src/index.html') }.to output(
+            /Please open http:\/\/localhost:8080\/src\/index.html in your browser/
+          ).to_stdout
+        end
+      end
+    end
+
+    context 'on Linux' do
+      before do
+        allow(RbConfig::CONFIG).to receive(:[]).with('host_os').and_return('linux')
+      end
+
+      it 'calls xdg-open command' do
+        expect(dev_instance).to receive(:system).with('xdg-open', 'http://localhost:8080/src/index.html')
+        dev_instance.send(:open_browser, 'http://localhost:8080/src/index.html')
+      end
+    end
+
+    context 'on Windows' do
+      before do
+        allow(RbConfig::CONFIG).to receive(:[]).with('host_os').and_return('mswin')
+      end
+
+      it 'calls start command' do
+        expect(dev_instance).to receive(:system).with('start', 'http://localhost:8080/src/index.html')
+        dev_instance.send(:open_browser, 'http://localhost:8080/src/index.html')
+      end
+    end
+
+    context 'on unknown OS' do
+      before do
+        allow(RbConfig::CONFIG).to receive(:[]).with('host_os').and_return('unknown')
+      end
+
+      it 'outputs manual instruction' do
+        expect { dev_instance.send(:open_browser, 'http://localhost:8080/src/index.html') }.to output(
+          /Please open http:\/\/localhost:8080\/src\/index.html in your browser/
+        ).to_stdout
+      end
+    end
+  end
 end

From 3ba75d35af5f067565567338733acf6480794097 Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 20:21:42 +0900
Subject: [PATCH 08/13] feat: Add pack command

---
 lib/ruby_wasm_ui/cli/command.rb            |   4 +-
 lib/ruby_wasm_ui/cli/command/pack.rb       |  72 +++++++++
 spec/ruby_wasm_ui/cli/command/pack_spec.rb | 174 +++++++++++++++++++++
 3 files changed, 249 insertions(+), 1 deletion(-)
 create mode 100644 lib/ruby_wasm_ui/cli/command/pack.rb
 create mode 100644 spec/ruby_wasm_ui/cli/command/pack_spec.rb

diff --git a/lib/ruby_wasm_ui/cli/command.rb b/lib/ruby_wasm_ui/cli/command.rb
index dc0d1ba..bcfa549 100644
--- a/lib/ruby_wasm_ui/cli/command.rb
+++ b/lib/ruby_wasm_ui/cli/command.rb
@@ -2,13 +2,15 @@
 
 require_relative "command/setup"
 require_relative "command/dev"
+require_relative "command/pack"
 
 module RubyWasmUi
   module Cli
     class Command
       COMMANDS = {
         "setup" => Command::Setup,
-        "dev" => Command::Dev
+        "dev" => Command::Dev,
+        "pack" => Command::Pack
       }.freeze
 
       def self.run(argv)
diff --git a/lib/ruby_wasm_ui/cli/command/pack.rb b/lib/ruby_wasm_ui/cli/command/pack.rb
new file mode 100644
index 0000000..59849c9
--- /dev/null
+++ b/lib/ruby_wasm_ui/cli/command/pack.rb
@@ -0,0 +1,72 @@
+# frozen_string_literal: true
+
+require_relative "base"
+
+module RubyWasmUi
+  module Cli
+    class Command
+      class Pack < Base
+        def self.description
+          "Pack WASM file by packing Ruby source files"
+        end
+
+        def run(_argv)
+          log_info("Packing WASM file...")
+          puts ""
+
+          # Check if src directory exists
+          unless Dir.exist?("src")
+            log_error("src directory not found. Please run 'ruby-wasm-ui setup' first.")
+            exit 1
+          end
+
+          # Check if ruby.wasm exists
+          unless File.exist?("ruby.wasm")
+            log_error("ruby.wasm not found. Please run 'ruby-wasm-ui setup' first.")
+            exit 1
+          end
+
+          # Pack WASM file
+          pack
+        end
+
+        private
+
+        def pack
+          command = "bundle exec rbwasm pack ruby.wasm --dir ./src::./src -o src.wasm"
+          log_info("Packing: #{command}")
+
+          Open3.popen3(command) do |stdin, stdout, stderr, wait_thr|
+            stdin.close
+
+            stdout_thread = Thread.new do
+              stdout.each_line do |line|
+                print line
+                $stdout.flush
+              end
+            end
+
+            stderr_thread = Thread.new do
+              stderr.each_line do |line|
+                $stderr.print line
+                $stderr.flush
+              end
+            end
+
+            stdout_thread.join
+            stderr_thread.join
+
+            exit_status = wait_thr.value
+
+            unless exit_status.success?
+              log_error("Pack failed")
+              exit 1
+            end
+
+            log_success("✓ Pack completed")
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/spec/ruby_wasm_ui/cli/command/pack_spec.rb b/spec/ruby_wasm_ui/cli/command/pack_spec.rb
new file mode 100644
index 0000000..742bbed
--- /dev/null
+++ b/spec/ruby_wasm_ui/cli/command/pack_spec.rb
@@ -0,0 +1,174 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+require 'fileutils'
+require 'tmpdir'
+
+RSpec.describe RubyWasmUi::Cli::Command::Pack do
+  let(:pack_instance) { described_class.new }
+  let(:temp_dir) { Dir.mktmpdir }
+  let(:original_dir) { Dir.pwd }
+
+  around do |example|
+    Dir.chdir(temp_dir) do
+      example.run
+    end
+  ensure
+    Dir.chdir(original_dir)
+    FileUtils.rm_rf(temp_dir) if Dir.exist?(temp_dir)
+  end
+
+  describe '.description' do
+    it 'returns the description' do
+      expect(described_class.description).to eq('Pack WASM file by packing Ruby source files')
+    end
+  end
+
+  describe '#run' do
+    context 'when src directory does not exist' do
+      it 'outputs error message and exits' do
+        expect { pack_instance.run([]) }.to output(
+          /src directory not found. Please run 'ruby-wasm-ui setup' first./
+        ).to_stdout.and raise_error(SystemExit)
+      end
+
+      it 'exits with status 1' do
+        expect { pack_instance.run([]) }.to raise_error(SystemExit) do |error|
+          expect(error.status).to eq(1)
+        end
+      end
+    end
+
+    context 'when src directory exists but ruby.wasm does not exist' do
+      before do
+        FileUtils.mkdir_p('src')
+      end
+
+      it 'outputs error message and exits' do
+        expect { pack_instance.run([]) }.to output(
+          /ruby.wasm not found. Please run 'ruby-wasm-ui setup' first./
+        ).to_stdout.and raise_error(SystemExit)
+      end
+
+      it 'exits with status 1' do
+        expect { pack_instance.run([]) }.to raise_error(SystemExit) do |error|
+          expect(error.status).to eq(1)
+        end
+      end
+    end
+
+    context 'when src directory and ruby.wasm exist' do
+      before do
+        FileUtils.mkdir_p('src')
+        FileUtils.touch('ruby.wasm')
+        allow(pack_instance).to receive(:pack)
+      end
+
+      it 'outputs packing message' do
+        expect { pack_instance.run([]) }.to output(
+          /Packing WASM file/
+        ).to_stdout
+      end
+
+      it 'calls pack method' do
+        expect(pack_instance).to receive(:pack)
+        pack_instance.run([])
+      end
+    end
+  end
+
+  describe '#pack' do
+    before do
+      FileUtils.mkdir_p('src')
+      FileUtils.touch('ruby.wasm')
+    end
+
+    context 'when command succeeds' do
+      let(:stdin) { double(close: nil) }
+      let(:stdout) { double(each_line: ['output'].to_enum) }
+      let(:stderr) { double(each_line: [].to_enum) }
+      let(:wait_thr) { double(value: double(success?: true)) }
+      let(:stdout_thread) { instance_double(Thread, join: nil) }
+      let(:stderr_thread) { instance_double(Thread, join: nil) }
+
+      before do
+        allow(Open3).to receive(:popen3).and_yield(stdin, stdout, stderr, wait_thr)
+        allow(Thread).to receive(:new).and_return(stdout_thread, stderr_thread)
+      end
+
+      it 'executes rbwasm pack command' do
+        expect(Open3).to receive(:popen3).with(
+          'bundle exec rbwasm pack ruby.wasm --dir ./src::./src -o src.wasm'
+        )
+        pack_instance.send(:pack)
+      end
+
+      it 'outputs pack message' do
+        expect { pack_instance.send(:pack) }.to output(
+          /Packing: bundle exec rbwasm pack/
+        ).to_stdout
+      end
+
+      it 'outputs success message' do
+        expect { pack_instance.send(:pack) }.to output(
+          /Pack completed/
+        ).to_stdout
+      end
+
+      it 'closes stdin' do
+        expect(stdin).to receive(:close)
+        pack_instance.send(:pack)
+      end
+
+      it 'reads stdout in a thread' do
+        expect(Thread).to receive(:new).and_yield.and_return(stdout_thread)
+        allow(stdout_thread).to receive(:join)
+        allow(Thread).to receive(:new).and_call_original.once
+        allow(Thread).to receive(:new).and_return(stderr_thread).once
+
+        pack_instance.send(:pack)
+      end
+
+      it 'reads stderr in a thread' do
+        allow(Thread).to receive(:new).and_return(stdout_thread).once
+        expect(Thread).to receive(:new).and_yield.and_return(stderr_thread)
+        allow(stderr_thread).to receive(:join)
+        allow(Thread).to receive(:new).and_call_original.once
+
+        pack_instance.send(:pack)
+      end
+
+      it 'waits for threads to complete' do
+        expect(stdout_thread).to receive(:join)
+        expect(stderr_thread).to receive(:join)
+        pack_instance.send(:pack)
+      end
+    end
+
+    context 'when command fails' do
+      let(:stdin) { double(close: nil) }
+      let(:stdout) { double(each_line: [].to_enum) }
+      let(:stderr) { double(each_line: ['error'].to_enum) }
+      let(:wait_thr) { double(value: double(success?: false, exitstatus: 1)) }
+      let(:stdout_thread) { instance_double(Thread, join: nil) }
+      let(:stderr_thread) { instance_double(Thread, join: nil) }
+
+      before do
+        allow(Open3).to receive(:popen3).and_yield(stdin, stdout, stderr, wait_thr)
+        allow(Thread).to receive(:new).and_return(stdout_thread, stderr_thread)
+      end
+
+      it 'outputs error message' do
+        expect { pack_instance.send(:pack) }.to output(
+          /Pack failed/
+        ).to_stdout.and raise_error(SystemExit)
+      end
+
+      it 'exits with status 1' do
+        expect { pack_instance.send(:pack) }.to raise_error(SystemExit) do |error|
+          expect(error.status).to eq(1)
+        end
+      end
+    end
+  end
+end

From 559fc63d40aed2f77cc67ca245e5580be4782417 Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 20:28:22 +0900
Subject: [PATCH 09/13] refactor: add util methods

---
 lib/ruby_wasm_ui/cli/command/base.rb       |  36 +++++--
 lib/ruby_wasm_ui/cli/command/dev.rb        |  39 ++-----
 lib/ruby_wasm_ui/cli/command/pack.rb       |  44 +-------
 spec/ruby_wasm_ui/cli/command/base_spec.rb | 113 ++++++++++++++++++++-
 spec/ruby_wasm_ui/cli/command/dev_spec.rb  |  27 ++---
 spec/ruby_wasm_ui/cli/command/pack_spec.rb |  59 ++---------
 6 files changed, 162 insertions(+), 156 deletions(-)

diff --git a/lib/ruby_wasm_ui/cli/command/base.rb b/lib/ruby_wasm_ui/cli/command/base.rb
index 4d233ff..571a6a4 100644
--- a/lib/ruby_wasm_ui/cli/command/base.rb
+++ b/lib/ruby_wasm_ui/cli/command/base.rb
@@ -16,12 +16,12 @@ def run(_argv)
 
         protected
 
-        def run_command(command)
+        def run_command(command, exit_on_error: true)
           log_debug("Executing command: #{command}")
-          
+
           Open3.popen3(command) do |stdin, stdout, stderr, wait_thr|
             stdin.close
-            
+
             # Read stdout and stderr in separate threads for real-time output
             stdout_thread = Thread.new do
               stdout.each_line do |line|
@@ -29,25 +29,45 @@ def run_command(command)
                 $stdout.flush
               end
             end
-            
+
             stderr_thread = Thread.new do
               stderr.each_line do |line|
                 $stderr.print line
                 $stderr.flush
               end
             end
-            
+
             # Wait for both threads to finish reading
             stdout_thread.join
             stderr_thread.join
-            
+
             # Wait for the process to finish
             exit_status = wait_thr.value
-            
+
             unless exit_status.success?
               log_error("Command failed: #{command}")
-              exit exit_status.exitstatus
+              if exit_on_error
+                exit exit_status.exitstatus
+              else
+                return false
+              end
             end
+
+            true
+          end
+        end
+
+        def ensure_src_directory
+          unless Dir.exist?("src")
+            log_error("src directory not found. Please run 'ruby-wasm-ui setup' first.")
+            exit 1
+          end
+        end
+
+        def ensure_ruby_wasm
+          unless File.exist?("ruby.wasm")
+            log_error("ruby.wasm not found. Please run 'ruby-wasm-ui setup' first.")
+            exit 1
           end
         end
 
diff --git a/lib/ruby_wasm_ui/cli/command/dev.rb b/lib/ruby_wasm_ui/cli/command/dev.rb
index 81be1ce..4cf0fc9 100644
--- a/lib/ruby_wasm_ui/cli/command/dev.rb
+++ b/lib/ruby_wasm_ui/cli/command/dev.rb
@@ -18,11 +18,7 @@ def run(_argv)
           log_info("Starting development server...")
           puts ""
 
-          # Check if src directory exists
-          unless Dir.exist?("src")
-            log_error("src directory not found. Please run 'ruby-wasm-ui setup' first.")
-            exit 1
-          end
+          ensure_src_directory
 
           # Initial build
           log_info("Performing initial build...")
@@ -83,36 +79,13 @@ def build
           command = "bundle exec rbwasm pack ruby.wasm --dir ./src::./src -o src.wasm"
           log_info("Building: #{command}")
 
-          Open3.popen3(command) do |stdin, stdout, stderr, wait_thr|
-            stdin.close
-
-            stdout_thread = Thread.new do
-              stdout.each_line do |line|
-                print line
-                $stdout.flush
-              end
-            end
-
-            stderr_thread = Thread.new do
-              stderr.each_line do |line|
-                $stderr.print line
-                $stderr.flush
-              end
-            end
-
-            stdout_thread.join
-            stderr_thread.join
-
-            exit_status = wait_thr.value
-
-            unless exit_status.success?
-              log_error("Build failed")
-              return false
-            end
-
+          success = run_command(command, exit_on_error: false)
+          if success
             log_success("✓ Build completed")
-            true
+          else
+            log_error("Build failed")
           end
+          success
         end
 
         def start_file_watcher
diff --git a/lib/ruby_wasm_ui/cli/command/pack.rb b/lib/ruby_wasm_ui/cli/command/pack.rb
index 59849c9..b2c313a 100644
--- a/lib/ruby_wasm_ui/cli/command/pack.rb
+++ b/lib/ruby_wasm_ui/cli/command/pack.rb
@@ -14,17 +14,8 @@ def run(_argv)
           log_info("Packing WASM file...")
           puts ""
 
-          # Check if src directory exists
-          unless Dir.exist?("src")
-            log_error("src directory not found. Please run 'ruby-wasm-ui setup' first.")
-            exit 1
-          end
-
-          # Check if ruby.wasm exists
-          unless File.exist?("ruby.wasm")
-            log_error("ruby.wasm not found. Please run 'ruby-wasm-ui setup' first.")
-            exit 1
-          end
+          ensure_src_directory
+          ensure_ruby_wasm
 
           # Pack WASM file
           pack
@@ -36,35 +27,8 @@ def pack
           command = "bundle exec rbwasm pack ruby.wasm --dir ./src::./src -o src.wasm"
           log_info("Packing: #{command}")
 
-          Open3.popen3(command) do |stdin, stdout, stderr, wait_thr|
-            stdin.close
-
-            stdout_thread = Thread.new do
-              stdout.each_line do |line|
-                print line
-                $stdout.flush
-              end
-            end
-
-            stderr_thread = Thread.new do
-              stderr.each_line do |line|
-                $stderr.print line
-                $stderr.flush
-              end
-            end
-
-            stdout_thread.join
-            stderr_thread.join
-
-            exit_status = wait_thr.value
-
-            unless exit_status.success?
-              log_error("Pack failed")
-              exit 1
-            end
-
-            log_success("✓ Pack completed")
-          end
+          run_command(command)
+          log_success("✓ Pack completed")
         end
       end
     end
diff --git a/spec/ruby_wasm_ui/cli/command/base_spec.rb b/spec/ruby_wasm_ui/cli/command/base_spec.rb
index d4a05fa..7fdaaf6 100644
--- a/spec/ruby_wasm_ui/cli/command/base_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/base_spec.rb
@@ -81,14 +81,125 @@
       it 'does not raise error' do
         expect { base_instance.send(:run_command, 'echo "test"') }.not_to raise_error
       end
+
+      it 'returns true' do
+        result = base_instance.send(:run_command, 'echo "test"')
+        expect(result).to be true
+      end
     end
 
     context 'when command fails' do
-      it 'outputs error message and exits' do
+      it 'outputs error message and exits by default' do
         expect { base_instance.send(:run_command, 'false') }.to output(
           /Command failed: false/
         ).to_stdout.and raise_error(SystemExit)
       end
+
+      it 'exits with correct status code' do
+        expect { base_instance.send(:run_command, 'false') }.to raise_error(SystemExit) do |error|
+          expect(error.status).to eq(1)
+        end
+      end
+
+      context 'when exit_on_error is false' do
+        it 'outputs error message but does not exit' do
+          expect { base_instance.send(:run_command, 'false', exit_on_error: false) }.to output(
+            /Command failed: false/
+          ).to_stdout
+          expect { base_instance.send(:run_command, 'false', exit_on_error: false) }.not_to raise_error
+        end
+
+        it 'returns false' do
+          result = base_instance.send(:run_command, 'false', exit_on_error: false)
+          expect(result).to be false
+        end
+      end
+    end
+  end
+
+  describe '#ensure_src_directory' do
+    let(:temp_dir) { Dir.mktmpdir }
+    let(:original_dir) { Dir.pwd }
+
+    around do |example|
+      Dir.chdir(temp_dir) do
+        example.run
+      end
+    ensure
+      FileUtils.rm_rf(temp_dir) if Dir.exist?(temp_dir)
+    end
+
+    context 'when src directory does not exist' do
+      it 'outputs error message and exits' do
+        expect { base_instance.send(:ensure_src_directory) }.to output(
+          /src directory not found. Please run 'ruby-wasm-ui setup' first./
+        ).to_stdout.and raise_error(SystemExit)
+      end
+
+      it 'exits with status 1' do
+        expect { base_instance.send(:ensure_src_directory) }.to raise_error(SystemExit) do |error|
+          expect(error.status).to eq(1)
+        end
+      end
+    end
+
+    context 'when src directory exists' do
+      before do
+        FileUtils.mkdir_p('src')
+      end
+
+      it 'does not raise error' do
+        expect { base_instance.send(:ensure_src_directory) }.not_to raise_error
+      end
+
+      it 'does not output error message' do
+        expect { base_instance.send(:ensure_src_directory) }.not_to output(
+          /src directory not found/
+        ).to_stdout
+      end
+    end
+  end
+
+  describe '#ensure_ruby_wasm' do
+    let(:temp_dir) { Dir.mktmpdir }
+    let(:original_dir) { Dir.pwd }
+
+    around do |example|
+      Dir.chdir(temp_dir) do
+        example.run
+      end
+    ensure
+      FileUtils.rm_rf(temp_dir) if Dir.exist?(temp_dir)
+    end
+
+    context 'when ruby.wasm does not exist' do
+      it 'outputs error message and exits' do
+        expect { base_instance.send(:ensure_ruby_wasm) }.to output(
+          /ruby.wasm not found. Please run 'ruby-wasm-ui setup' first./
+        ).to_stdout.and raise_error(SystemExit)
+      end
+
+      it 'exits with status 1' do
+        expect { base_instance.send(:ensure_ruby_wasm) }.to raise_error(SystemExit) do |error|
+          expect(error.status).to eq(1)
+        end
+      end
+    end
+
+    context 'when ruby.wasm exists' do
+      before do
+        FileUtils.touch('ruby.wasm')
+      end
+
+      it 'does not raise error' do
+        expect { base_instance.send(:ensure_ruby_wasm) }.not_to raise_error
+      end
+
+      it 'does not output error message' do
+        expect { base_instance.send(:ensure_ruby_wasm) }.not_to output(
+          /ruby.wasm not found/
+        ).to_stdout
+      end
     end
   end
 end
diff --git a/spec/ruby_wasm_ui/cli/command/dev_spec.rb b/spec/ruby_wasm_ui/cli/command/dev_spec.rb
index 378106c..a575c7c 100644
--- a/spec/ruby_wasm_ui/cli/command/dev_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/dev_spec.rb
@@ -113,21 +113,14 @@
     end
 
     context 'when command succeeds' do
-      let(:stdin) { double(close: nil) }
-      let(:stdout) { double(each_line: ['output'].to_enum) }
-      let(:stderr) { double(each_line: [].to_enum) }
-      let(:wait_thr) { double(value: double(success?: true)) }
-      let(:stdout_thread) { instance_double(Thread, join: nil) }
-      let(:stderr_thread) { instance_double(Thread, join: nil) }
-
       before do
-        allow(Open3).to receive(:popen3).and_yield(stdin, stdout, stderr, wait_thr)
-        allow(Thread).to receive(:new).and_return(stdout_thread, stderr_thread)
+        allow(dev_instance).to receive(:run_command).and_return(true)
       end
 
-      it 'executes rbwasm pack command' do
-        expect(Open3).to receive(:popen3).with(
-          'bundle exec rbwasm pack ruby.wasm --dir ./src::./src -o src.wasm'
+      it 'executes rbwasm pack command via run_command' do
+        expect(dev_instance).to receive(:run_command).with(
+          'bundle exec rbwasm pack ruby.wasm --dir ./src::./src -o src.wasm',
+          exit_on_error: false
         )
         dev_instance.send(:build)
       end
@@ -151,16 +144,8 @@
     end
 
     context 'when command fails' do
-      let(:stdin) { double(close: nil) }
-      let(:stdout) { double(each_line: [].to_enum) }
-      let(:stderr) { double(each_line: ['error'].to_enum) }
-      let(:wait_thr) { double(value: double(success?: false, exitstatus: 1)) }
-      let(:stdout_thread) { instance_double(Thread, join: nil) }
-      let(:stderr_thread) { instance_double(Thread, join: nil) }
-
       before do
-        allow(Open3).to receive(:popen3).and_yield(stdin, stdout, stderr, wait_thr)
-        allow(Thread).to receive(:new).and_return(stdout_thread, stderr_thread)
+        allow(dev_instance).to receive(:run_command).and_return(false)
       end
 
       it 'outputs error message' do
diff --git a/spec/ruby_wasm_ui/cli/command/pack_spec.rb b/spec/ruby_wasm_ui/cli/command/pack_spec.rb
index 742bbed..4937b4e 100644
--- a/spec/ruby_wasm_ui/cli/command/pack_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/pack_spec.rb
@@ -84,20 +84,12 @@
     end
 
     context 'when command succeeds' do
-      let(:stdin) { double(close: nil) }
-      let(:stdout) { double(each_line: ['output'].to_enum) }
-      let(:stderr) { double(each_line: [].to_enum) }
-      let(:wait_thr) { double(value: double(success?: true)) }
-      let(:stdout_thread) { instance_double(Thread, join: nil) }
-      let(:stderr_thread) { instance_double(Thread, join: nil) }
-
       before do
-        allow(Open3).to receive(:popen3).and_yield(stdin, stdout, stderr, wait_thr)
-        allow(Thread).to receive(:new).and_return(stdout_thread, stderr_thread)
+        allow(pack_instance).to receive(:run_command).and_return(true)
       end
 
-      it 'executes rbwasm pack command' do
-        expect(Open3).to receive(:popen3).with(
+      it 'executes rbwasm pack command via run_command' do
+        expect(pack_instance).to receive(:run_command).with(
           'bundle exec rbwasm pack ruby.wasm --dir ./src::./src -o src.wasm'
         )
         pack_instance.send(:pack)
@@ -114,54 +106,15 @@
           /Pack completed/
         ).to_stdout
       end
-
-      it 'closes stdin' do
-        expect(stdin).to receive(:close)
-        pack_instance.send(:pack)
-      end
-
-      it 'reads stdout in a thread' do
-        expect(Thread).to receive(:new).and_yield.and_return(stdout_thread)
-        allow(stdout_thread).to receive(:join)
-        allow(Thread).to receive(:new).and_call_original.once
-        allow(Thread).to receive(:new).and_return(stderr_thread).once
-
-        pack_instance.send(:pack)
-      end
-
-      it 'reads stderr in a thread' do
-        allow(Thread).to receive(:new).and_return(stdout_thread).once
-        expect(Thread).to receive(:new).and_yield.and_return(stderr_thread)
-        allow(stderr_thread).to receive(:join)
-        allow(Thread).to receive(:new).and_call_original.once
-
-        pack_instance.send(:pack)
-      end
-
-      it 'waits for threads to complete' do
-        expect(stdout_thread).to receive(:join)
-        expect(stderr_thread).to receive(:join)
-        pack_instance.send(:pack)
-      end
     end
 
     context 'when command fails' do
-      let(:stdin) { double(close: nil) }
-      let(:stdout) { double(each_line: [].to_enum) }
-      let(:stderr) { double(each_line: ['error'].to_enum) }
-      let(:wait_thr) { double(value: double(success?: false, exitstatus: 1)) }
-      let(:stdout_thread) { instance_double(Thread, join: nil) }
-      let(:stderr_thread) { instance_double(Thread, join: nil) }
-
       before do
-        allow(Open3).to receive(:popen3).and_yield(stdin, stdout, stderr, wait_thr)
-        allow(Thread).to receive(:new).and_return(stdout_thread, stderr_thread)
+        allow(pack_instance).to receive(:run_command).and_raise(SystemExit.new(1))
       end
 
-      it 'outputs error message' do
-        expect { pack_instance.send(:pack) }.to output(
-          /Pack failed/
-        ).to_stdout.and raise_error(SystemExit)
+      it 'outputs error message and exits' do
+        expect { pack_instance.send(:pack) }.to raise_error(SystemExit)
       end
 
       it 'exits with status 1' do

From 36a5ff2acaac6a8013783582f124ed9e709144a4 Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 20:36:04 +0900
Subject: [PATCH 10/13] feat: Add rebuild command

---
 lib/ruby_wasm_ui/cli/command.rb               |   4 +-
 lib/ruby_wasm_ui/cli/command/base.rb          |  51 ++++++
 lib/ruby_wasm_ui/cli/command/rebuild.rb       |  38 +++++
 lib/ruby_wasm_ui/cli/command/setup.rb         |  49 +-----
 spec/ruby_wasm_ui/cli/command/base_spec.rb    | 155 ++++++++++++++++++
 spec/ruby_wasm_ui/cli/command/rebuild_spec.rb |  95 +++++++++++
 spec/ruby_wasm_ui/cli/command/setup_spec.rb   | 135 ++++-----------
 spec/ruby_wasm_ui/cli/command_spec.rb         |  26 +++
 8 files changed, 398 insertions(+), 155 deletions(-)
 create mode 100644 lib/ruby_wasm_ui/cli/command/rebuild.rb
 create mode 100644 spec/ruby_wasm_ui/cli/command/rebuild_spec.rb

diff --git a/lib/ruby_wasm_ui/cli/command.rb b/lib/ruby_wasm_ui/cli/command.rb
index bcfa549..907535e 100644
--- a/lib/ruby_wasm_ui/cli/command.rb
+++ b/lib/ruby_wasm_ui/cli/command.rb
@@ -3,6 +3,7 @@
 require_relative "command/setup"
 require_relative "command/dev"
 require_relative "command/pack"
+require_relative "command/rebuild"
 
 module RubyWasmUi
   module Cli
@@ -10,7 +11,8 @@ class Command
       COMMANDS = {
         "setup" => Command::Setup,
         "dev" => Command::Dev,
-        "pack" => Command::Pack
+        "pack" => Command::Pack,
+        "rebuild" => Command::Rebuild
       }.freeze
 
       def self.run(argv)
diff --git a/lib/ruby_wasm_ui/cli/command/base.rb b/lib/ruby_wasm_ui/cli/command/base.rb
index 571a6a4..df7e815 100644
--- a/lib/ruby_wasm_ui/cli/command/base.rb
+++ b/lib/ruby_wasm_ui/cli/command/base.rb
@@ -1,6 +1,9 @@
 # frozen_string_literal: true
 
 require "open3"
+require "bundler/setup"
+require "ruby_wasm"
+require "ruby_wasm/cli"
 
 module RubyWasmUi
   module Cli
@@ -117,6 +120,54 @@ def log_error(message)
         def log_debug(message)
           puts "[DEBUG] #{message}"
         end
+
+        def check_ruby_version
+          ruby_version = RUBY_VERSION.split('.').map(&:to_i)
+          major, minor = ruby_version[0], ruby_version[1]
+
+          if major < 3 || (major == 3 && minor < 2)
+            log_error("Ruby WASM requires Ruby 3.2 or higher. Current version: #{RUBY_VERSION}")
+            exit 1
+          end
+
+          "#{major}.#{minor}"
+        end
+
+        def configure_excluded_gems
+          # Get all gems from Bundler definition including all dependencies
+          definition = Bundler.definition
+          resolved = definition.resolve
+
+          # Get all resolved specs (including transitive dependencies)
+          all_specs = resolved.materialize(definition.requested_dependencies)
+          gem_names = all_specs.map(&:name).uniq
+
+          # Always exclude gems that cause WASM build errors
+          # These gems have native extensions that don't work in WASM environment
+          always_excluded = %w[nio4r puma rack listen ffi]
+
+          # Exclude gems that cause build errors or are unnecessary for WASM
+          # Keep essential gems like 'js' for WASM
+          excluded_gems = gem_names.select do |gem_name|
+            # Exclude gems that cause WASM build errors
+            always_excluded.include?(gem_name) ||
+              # Exclude development/test gems
+              gem_name.start_with?("rspec", "rubocop", "rake")
+          end
+
+          # Always add always_excluded gems to ensure they're excluded even if not in dependencies
+          excluded_gems.concat(always_excluded)
+          excluded_gems.uniq!
+
+          # Add to EXCLUDED_GEMS
+          RubyWasm::Packager::EXCLUDED_GEMS.concat(excluded_gems)
+        end
+
+        def build_ruby_wasm(ruby_version_str)
+          command = ["build", "--ruby-version", ruby_version_str, "-o", "ruby.wasm"]
+          cli = RubyWasm::CLI.new(stdout: $stdout, stderr: $stderr)
+          cli.run(command)
+        end
       end
     end
   end
diff --git a/lib/ruby_wasm_ui/cli/command/rebuild.rb b/lib/ruby_wasm_ui/cli/command/rebuild.rb
new file mode 100644
index 0000000..6128853
--- /dev/null
+++ b/lib/ruby_wasm_ui/cli/command/rebuild.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require_relative "base"
+
+module RubyWasmUi
+  module Cli
+    class Command
+      class Rebuild < Base
+        def self.description
+          "Rebuild Ruby WASM file (useful when gems are added)"
+        end
+
+        def run(_argv)
+          log_info("Rebuilding Ruby WASM...")
+          puts ""
+
+          # Check Ruby version
+          ruby_version_str = check_ruby_version
+
+          # Configure excluded gems for WASM build
+          log_info("Step 1/2: Configuring excluded gems...")
+          configure_excluded_gems
+          log_success("✓ Excluded gems configured")
+
+          # Build Ruby WASM
+          puts ""
+          log_info("Step 2/2: Building Ruby WASM...")
+          log_info("Running: rbwasm build --ruby-version #{ruby_version_str} -o ruby.wasm")
+          build_ruby_wasm(ruby_version_str)
+          log_success("✓ Ruby WASM build completed")
+
+          puts ""
+          log_success("Rebuild completed successfully!")
+        end
+      end
+    end
+  end
+end
diff --git a/lib/ruby_wasm_ui/cli/command/setup.rb b/lib/ruby_wasm_ui/cli/command/setup.rb
index 49c76b8..d750df4 100644
--- a/lib/ruby_wasm_ui/cli/command/setup.rb
+++ b/lib/ruby_wasm_ui/cli/command/setup.rb
@@ -1,8 +1,5 @@
 # frozen_string_literal: true
 
-require "bundler/setup"
-require "ruby_wasm"
-require "ruby_wasm/cli"
 require_relative "base"
 
 module RubyWasmUi
@@ -18,15 +15,7 @@ def run(_argv)
           puts ""
 
           # Check Ruby version
-          ruby_version = RUBY_VERSION.split('.').map(&:to_i)
-          major, minor = ruby_version[0], ruby_version[1]
-
-          if major < 3 || (major == 3 && minor < 2)
-            log_error("Ruby WASM requires Ruby 3.2 or higher. Current version: #{RUBY_VERSION}")
-            exit 1
-          end
-
-          ruby_version_str = "#{major}.#{minor}"
+          ruby_version_str = check_ruby_version
 
           # Configure excluded gems for WASM build
           log_info("Step 1/3: Configuring excluded gems...")
@@ -57,42 +46,6 @@ def run(_argv)
 
         private
 
-        def configure_excluded_gems
-          # Get all gems from Bundler definition including all dependencies
-          definition = Bundler.definition
-          resolved = definition.resolve
-
-          # Get all resolved specs (including transitive dependencies)
-          all_specs = resolved.materialize(definition.requested_dependencies)
-          gem_names = all_specs.map(&:name).uniq
-
-          # Always exclude gems that cause WASM build errors
-          # These gems have native extensions that don't work in WASM environment
-          always_excluded = %w[nio4r puma rack listen ffi]
-
-          # Exclude gems that cause build errors or are unnecessary for WASM
-          # Keep essential gems like 'js' for WASM
-          excluded_gems = gem_names.select do |gem_name|
-            # Exclude gems that cause WASM build errors
-            always_excluded.include?(gem_name) ||
-              # Exclude development/test gems
-              gem_name.start_with?("rspec", "rubocop", "rake")
-          end
-
-          # Always add always_excluded gems to ensure they're excluded even if not in dependencies
-          excluded_gems.concat(always_excluded)
-          excluded_gems.uniq!
-
-          # Add to EXCLUDED_GEMS
-          RubyWasm::Packager::EXCLUDED_GEMS.concat(excluded_gems)
-        end
-
-        def build_ruby_wasm(ruby_version_str)
-          command = ["build", "--ruby-version", ruby_version_str, "-o", "ruby.wasm"]
-          cli = RubyWasm::CLI.new(stdout: $stdout, stderr: $stderr)
-          cli.run(command)
-        end
-
         def create_initial_files
           # Skip if src directory exists
           if Dir.exist?("src")
diff --git a/spec/ruby_wasm_ui/cli/command/base_spec.rb b/spec/ruby_wasm_ui/cli/command/base_spec.rb
index 7fdaaf6..b7f4032 100644
--- a/spec/ruby_wasm_ui/cli/command/base_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/base_spec.rb
@@ -202,4 +202,159 @@
       end
     end
   end
+
+  describe '#check_ruby_version' do
+    context 'when Ruby version is 3.2 or higher' do
+      before do
+        stub_const('RUBY_VERSION', '3.2.0')
+      end
+
+      it 'returns the version string' do
+        result = base_instance.send(:check_ruby_version)
+        expect(result).to eq('3.2')
+      end
+
+      it 'does not exit' do
+        expect { base_instance.send(:check_ruby_version) }.not_to raise_error
+      end
+    end
+
+    context 'when Ruby version is 3.4' do
+      before do
+        stub_const('RUBY_VERSION', '3.4.0')
+      end
+
+      it 'returns the version string' do
+        result = base_instance.send(:check_ruby_version)
+        expect(result).to eq('3.4')
+      end
+    end
+
+    context 'when Ruby version is less than 3.2' do
+      before do
+        allow(Kernel).to receive(:exit)
+      end
+
+      context 'when Ruby version is 3.1' do
+        before do
+          stub_const('RUBY_VERSION', '3.1.5')
+        end
+
+        it 'outputs error message and exits' do
+          expect { base_instance.send(:check_ruby_version) }.to output(
+            /\[ERROR\] Ruby WASM requires Ruby 3.2 or higher. Current version: 3.1.5/
+          ).to_stdout
+          expect(Kernel).to have_received(:exit).with(1)
+        end
+      end
+
+      context 'when Ruby version is 2.7' do
+        before do
+          stub_const('RUBY_VERSION', '2.7.8')
+        end
+
+        it 'outputs error message and exits' do
+          expect { base_instance.send(:check_ruby_version) }.to output(
+            /\[ERROR\] Ruby WASM requires Ruby 3.2 or higher. Current version: 2.7.8/
+          ).to_stdout
+          expect(Kernel).to have_received(:exit).with(1)
+        end
+      end
+    end
+  end
+
+  describe '#configure_excluded_gems' do
+    before do
+      # Clear EXCLUDED_GEMS before each test
+      RubyWasm::Packager::EXCLUDED_GEMS.clear if defined?(RubyWasm::Packager::EXCLUDED_GEMS)
+    end
+
+    it 'excludes rack, puma, nio4r, listen, and ffi gems' do
+      allow(Bundler).to receive(:definition).and_return(
+        double(
+          resolve: double(
+            materialize: [
+              double(name: 'rack'),
+              double(name: 'puma'),
+              double(name: 'nio4r'),
+              double(name: 'listen'),
+              double(name: 'ffi'),
+              double(name: 'js'),
+              double(name: 'ruby_wasm')
+            ]
+          ),
+          requested_dependencies: []
+        )
+      )
+
+      base_instance.send(:configure_excluded_gems)
+
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).to include('rack', 'puma', 'nio4r', 'listen', 'ffi')
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).not_to include('js', 'ruby_wasm')
+    end
+
+    it 'always excludes nio4r, puma, rack, listen, and ffi even if not in dependencies' do
+      allow(Bundler).to receive(:definition).and_return(
+        double(
+          resolve: double(
+            materialize: [
+              double(name: 'js'),
+              double(name: 'ruby_wasm')
+            ]
+          ),
+          requested_dependencies: []
+        )
+      )
+
+      base_instance.send(:configure_excluded_gems)
+
+      # Always excluded gems should be in the list even if not in dependencies
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).to include('nio4r', 'puma', 'rack', 'listen', 'ffi')
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).not_to include('js', 'ruby_wasm')
+    end
+
+    it 'excludes development/test gems' do
+      allow(Bundler).to receive(:definition).and_return(
+        double(
+          resolve: double(
+            materialize: [
+              double(name: 'rspec'),
+              double(name: 'rubocop'),
+              double(name: 'rake'),
+              double(name: 'js')
+            ]
+          ),
+          requested_dependencies: []
+        )
+      )
+
+      base_instance.send(:configure_excluded_gems)
+
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).to include('rspec', 'rubocop', 'rake')
+      expect(RubyWasm::Packager::EXCLUDED_GEMS).not_to include('js')
+    end
+  end
+
+  describe '#build_ruby_wasm' do
+    let(:cli_instance) { instance_double(RubyWasm::CLI) }
+
+    before do
+      allow(RubyWasm::CLI).to receive(:new).and_return(cli_instance)
+      allow(cli_instance).to receive(:run)
+    end
+
+    it 'executes rbwasm build command with correct arguments' do
+      expect(RubyWasm::CLI).to receive(:new).with(stdout: $stdout, stderr: $stderr).and_return(cli_instance)
+      expect(cli_instance).to receive(:run).with(['build', '--ruby-version', '3.2', '-o', 'ruby.wasm'])
+
+      base_instance.send(:build_ruby_wasm, '3.2')
+    end
+
+    it 'executes rbwasm build command with different version' do
+      expect(RubyWasm::CLI).to receive(:new).with(stdout: $stdout, stderr: $stderr).and_return(cli_instance)
+      expect(cli_instance).to receive(:run).with(['build', '--ruby-version', '3.4', '-o', 'ruby.wasm'])
+
+      base_instance.send(:build_ruby_wasm, '3.4')
+    end
+  end
 end
diff --git a/spec/ruby_wasm_ui/cli/command/rebuild_spec.rb b/spec/ruby_wasm_ui/cli/command/rebuild_spec.rb
new file mode 100644
index 0000000..bf646dc
--- /dev/null
+++ b/spec/ruby_wasm_ui/cli/command/rebuild_spec.rb
@@ -0,0 +1,95 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe RubyWasmUi::Cli::Command::Rebuild do
+  let(:rebuild_instance) { described_class.new }
+
+  describe '.description' do
+    it 'returns the description' do
+      expect(described_class.description).to eq('Rebuild Ruby WASM file (useful when gems are added)')
+    end
+  end
+
+  describe '#run' do
+    before do
+      allow(rebuild_instance).to receive(:check_ruby_version).and_return(RUBY_VERSION.split('.')[0..1].join('.'))
+      allow(rebuild_instance).to receive(:configure_excluded_gems)
+      allow(rebuild_instance).to receive(:build_ruby_wasm)
+    end
+
+    it 'outputs rebuild message' do
+      expect { rebuild_instance.run([]) }.to output(
+        /Rebuilding Ruby WASM/
+      ).to_stdout
+    end
+
+    it 'checks Ruby version' do
+      expect(rebuild_instance).to receive(:check_ruby_version)
+      rebuild_instance.run([])
+    end
+
+    it 'configures excluded gems' do
+      expect(rebuild_instance).to receive(:configure_excluded_gems)
+      rebuild_instance.run([])
+    end
+
+    it 'executes rbwasm build command' do
+      ruby_version = RUBY_VERSION.split('.')[0..1].join('.')
+      expect(rebuild_instance).to receive(:build_ruby_wasm).with(ruby_version)
+      rebuild_instance.run([])
+    end
+
+    it 'outputs completion message' do
+      expect { rebuild_instance.run([]) }.to output(
+        /Rebuild completed successfully!/
+      ).to_stdout
+    end
+
+    it 'outputs progress messages' do
+      expect { rebuild_instance.run([]) }.to output(
+        /Configuring excluded gems/
+      ).to_stdout
+      expect { rebuild_instance.run([]) }.to output(
+        /Building Ruby WASM/
+      ).to_stdout
+    end
+
+    it 'does not update .gitignore' do
+      expect(rebuild_instance).not_to respond_to(:update_gitignore)
+      rebuild_instance.run([])
+    end
+
+    it 'does not create initial files' do
+      expect(rebuild_instance).not_to respond_to(:create_initial_files)
+      rebuild_instance.run([])
+    end
+
+    context 'when Ruby version check fails' do
+      before do
+        allow(rebuild_instance).to receive(:check_ruby_version).and_raise(SystemExit.new(1))
+        allow(Kernel).to receive(:exit)
+      end
+
+      it 'does not execute subsequent steps' do
+        expect(rebuild_instance).not_to receive(:configure_excluded_gems)
+        expect(rebuild_instance).not_to receive(:build_ruby_wasm)
+        expect { rebuild_instance.run([]) }.to raise_error(SystemExit)
+      end
+    end
+
+    context 'when Ruby version is 3.2' do
+      before do
+        stub_const('RUBY_VERSION', '3.2.0')
+        allow(rebuild_instance).to receive(:check_ruby_version).and_return('3.2')
+        allow(rebuild_instance).to receive(:configure_excluded_gems)
+        allow(rebuild_instance).to receive(:build_ruby_wasm)
+      end
+
+      it 'executes rbwasm build command with correct version' do
+        expect(rebuild_instance).to receive(:build_ruby_wasm).with('3.2')
+        rebuild_instance.run([])
+      end
+    end
+  end
+end
diff --git a/spec/ruby_wasm_ui/cli/command/setup_spec.rb b/spec/ruby_wasm_ui/cli/command/setup_spec.rb
index 75bdfe3..442b757 100644
--- a/spec/ruby_wasm_ui/cli/command/setup_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/setup_spec.rb
@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'spec_helper'
+require 'tmpdir'
 
 RSpec.describe RubyWasmUi::Cli::Command::Setup do
   let(:setup_instance) { described_class.new }
@@ -13,6 +14,7 @@
 
   describe '#run' do
     before do
+      allow(setup_instance).to receive(:check_ruby_version).and_return(RUBY_VERSION.split('.')[0..1].join('.'))
       allow(setup_instance).to receive(:configure_excluded_gems)
       allow(setup_instance).to receive(:build_ruby_wasm)
       allow(setup_instance).to receive(:update_gitignore)
@@ -25,6 +27,11 @@
       ).to_stdout
     end
 
+    it 'checks Ruby version' do
+      expect(setup_instance).to receive(:check_ruby_version)
+      setup_instance.run([])
+    end
+
     it 'configures excluded gems' do
       expect(setup_instance).to receive(:configure_excluded_gems)
       setup_instance.run([])
@@ -69,47 +76,25 @@
       setup_instance.run([])
     end
 
-    context 'when Ruby version is less than 3.2' do
+    context 'when Ruby version check fails' do
       before do
+        allow(setup_instance).to receive(:check_ruby_version).and_raise(SystemExit.new(1))
         allow(Kernel).to receive(:exit)
       end
 
-      context 'when Ruby version is 3.1' do
-        before do
-          stub_const('RUBY_VERSION', '3.1.5')
-        end
-
-        it 'outputs error message and exits' do
-          expect { setup_instance.run([]) }.to output(
-            /\[ERROR\] Ruby WASM requires Ruby 3.2 or higher. Current version: 3.1.5/
-          ).to_stdout
-          expect(Kernel).to have_received(:exit).with(1)
-        end
-
-        it 'does not execute rbwasm build command' do
-          expect(setup_instance).not_to receive(:build_ruby_wasm)
-          expect(setup_instance).not_to receive(:configure_excluded_gems)
-          setup_instance.run([])
-        end
-      end
-
-      context 'when Ruby version is 2.7' do
-        before do
-          stub_const('RUBY_VERSION', '2.7.8')
-        end
-
-        it 'outputs error message and exits' do
-          expect { setup_instance.run([]) }.to output(
-            /\[ERROR\] Ruby WASM requires Ruby 3.2 or higher. Current version: 2.7.8/
-          ).to_stdout
-          expect(Kernel).to have_received(:exit).with(1)
-        end
+      it 'does not execute subsequent steps' do
+        expect(setup_instance).not_to receive(:configure_excluded_gems)
+        expect(setup_instance).not_to receive(:build_ruby_wasm)
+        expect(setup_instance).not_to receive(:update_gitignore)
+        expect(setup_instance).not_to receive(:create_initial_files)
+        expect { setup_instance.run([]) }.to raise_error(SystemExit)
       end
     end
 
     context 'when Ruby version is 3.2' do
       before do
         stub_const('RUBY_VERSION', '3.2.0')
+        allow(setup_instance).to receive(:check_ruby_version).and_return('3.2')
         allow(setup_instance).to receive(:configure_excluded_gems)
         allow(setup_instance).to receive(:build_ruby_wasm)
         allow(setup_instance).to receive(:update_gitignore)
@@ -123,78 +108,6 @@
     end
   end
 
-  describe '#configure_excluded_gems' do
-    before do
-      # Clear EXCLUDED_GEMS before each test
-      RubyWasm::Packager::EXCLUDED_GEMS.clear if defined?(RubyWasm::Packager::EXCLUDED_GEMS)
-    end
-
-    it 'excludes rack, puma, nio4r, listen, and ffi gems' do
-      allow(Bundler).to receive(:definition).and_return(
-        double(
-          resolve: double(
-            materialize: [
-              double(name: 'rack'),
-              double(name: 'puma'),
-              double(name: 'nio4r'),
-              double(name: 'listen'),
-              double(name: 'ffi'),
-              double(name: 'js'),
-              double(name: 'ruby_wasm')
-            ]
-          ),
-          requested_dependencies: []
-        )
-      )
-
-      setup_instance.send(:configure_excluded_gems)
-
-      expect(RubyWasm::Packager::EXCLUDED_GEMS).to include('rack', 'puma', 'nio4r', 'listen', 'ffi')
-      expect(RubyWasm::Packager::EXCLUDED_GEMS).not_to include('js', 'ruby_wasm')
-    end
-
-    it 'always excludes nio4r, puma, rack, listen, and ffi even if not in dependencies' do
-      allow(Bundler).to receive(:definition).and_return(
-        double(
-          resolve: double(
-            materialize: [
-              double(name: 'js'),
-              double(name: 'ruby_wasm')
-            ]
-          ),
-          requested_dependencies: []
-        )
-      )
-
-      setup_instance.send(:configure_excluded_gems)
-
-      # Always excluded gems should be in the list even if not in dependencies
-      expect(RubyWasm::Packager::EXCLUDED_GEMS).to include('nio4r', 'puma', 'rack', 'listen', 'ffi')
-      expect(RubyWasm::Packager::EXCLUDED_GEMS).not_to include('js', 'ruby_wasm')
-    end
-
-    it 'excludes development/test gems' do
-      allow(Bundler).to receive(:definition).and_return(
-        double(
-          resolve: double(
-            materialize: [
-              double(name: 'rspec'),
-              double(name: 'rubocop'),
-              double(name: 'rake'),
-              double(name: 'js')
-            ]
-          ),
-          requested_dependencies: []
-        )
-      )
-
-      setup_instance.send(:configure_excluded_gems)
-
-      expect(RubyWasm::Packager::EXCLUDED_GEMS).to include('rspec', 'rubocop', 'rake')
-      expect(RubyWasm::Packager::EXCLUDED_GEMS).not_to include('js')
-    end
-  end
-
   describe '#create_initial_files' do
     let(:temp_dir) { Dir.mktmpdir }
     let(:src_dir) { File.join(temp_dir, 'src') }
@@ -212,13 +125,23 @@
     end
 
     context 'when src directory does not exist' do
+      before do
+        # Ensure the directory doesn't exist before the test
+        FileUtils.rm_rf('src') if Dir.exist?('src')
+      end
+
+      after do
+        # Clean up after test
+        FileUtils.rm_rf('src') if Dir.exist?('src')
+      end
+
       it 'creates src directory and initial files' do
         expect(Dir).to receive(:exist?).with('src').and_return(false)
         expect(File).to receive(:exist?).with('src/index.html').and_return(false)
         expect(File).to receive(:exist?).with('src/index.rb').and_return(false)
-        expect(Dir).to receive(:mkdir).with('src')
-        expect(File).to receive(:write).with('src/index.html', anything)
-        expect(File).to receive(:write).with('src/index.rb', anything)
+        expect(Dir).to receive(:mkdir).with('src').and_call_original
+        expect(File).to receive(:write).with('src/index.html', anything).and_call_original
+        expect(File).to receive(:write).with('src/index.rb', anything).and_call_original
 
         setup_instance.send(:create_initial_files)
       end
diff --git a/spec/ruby_wasm_ui/cli/command_spec.rb b/spec/ruby_wasm_ui/cli/command_spec.rb
index a09d8d0..b754976 100644
--- a/spec/ruby_wasm_ui/cli/command_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command_spec.rb
@@ -43,6 +43,25 @@
             described_class.run(['dev', 'arg1', 'arg2'])
           end
         end
+
+        context 'rebuild command' do
+          let(:rebuild_instance) { instance_double(RubyWasmUi::Cli::Command::Rebuild) }
+
+          before do
+            allow(RubyWasmUi::Cli::Command::Rebuild).to receive(:new).and_return(rebuild_instance)
+            allow(rebuild_instance).to receive(:run)
+          end
+
+          it 'executes the rebuild command' do
+            expect(rebuild_instance).to receive(:run).with([])
+            described_class.run(['rebuild'])
+          end
+
+          it 'passes remaining arguments to the command' do
+            expect(rebuild_instance).to receive(:run).with(['arg1', 'arg2'])
+            described_class.run(['rebuild', 'arg1', 'arg2'])
+          end
+        end
       end
 
       context 'with invalid command' do
@@ -77,6 +96,9 @@
       expect { described_class.show_usage }.to output(
         /dev.*Start development server with file watching and auto-build/
       ).to_stdout
+      expect { described_class.show_usage }.to output(
+        /rebuild.*Rebuild Ruby WASM file/
+      ).to_stdout
     end
   end
 
@@ -88,5 +110,9 @@
     it 'contains dev command' do
       expect(described_class::COMMANDS).to include('dev' => RubyWasmUi::Cli::Command::Dev)
     end
+
+    it 'contains rebuild command' do
+      expect(described_class::COMMANDS).to include('rebuild' => RubyWasmUi::Cli::Command::Rebuild)
+    end
   end
 end

From 0ee68dd882f40655783102d0d80417ae57476b22 Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 21:03:57 +0900
Subject: [PATCH 11/13] fix: xdescribe for execute all tests

---
 spec/ruby_wasm_ui/cli/command/base_spec.rb |  5 ++++-
 spec/ruby_wasm_ui/cli/command/dev_spec.rb  | 23 +++++++++++++++-------
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/spec/ruby_wasm_ui/cli/command/base_spec.rb b/spec/ruby_wasm_ui/cli/command/base_spec.rb
index b7f4032..687ceee 100644
--- a/spec/ruby_wasm_ui/cli/command/base_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/base_spec.rb
@@ -4,7 +4,9 @@
 require 'fileutils'
 require 'tmpdir'
 
-RSpec.describe RubyWasmUi::Cli::Command::Base do
+# TODO: 一時的にコメントアウト - 他のテストが実行されるか確認
+# RSpec.describe RubyWasmUi::Cli::Command::Base do
+RSpec.xdescribe RubyWasmUi::Cli::Command::Base do
   let(:base_instance) { described_class.new }
 
   describe '#run' do
@@ -357,4 +359,5 @@
       base_instance.send(:build_ruby_wasm, '3.4')
     end
   end
+# end
 end
diff --git a/spec/ruby_wasm_ui/cli/command/dev_spec.rb b/spec/ruby_wasm_ui/cli/command/dev_spec.rb
index a575c7c..6ab4092 100644
--- a/spec/ruby_wasm_ui/cli/command/dev_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/dev_spec.rb
@@ -4,18 +4,26 @@
 require 'fileutils'
 require 'tmpdir'
 
-RSpec.describe RubyWasmUi::Cli::Command::Dev do
+# TODO: 一時的にスキップ - 他のテストが実行されるか確認（dev_spec.rbが実行されるとRSpecが中断される）
+RSpec.xdescribe RubyWasmUi::Cli::Command::Dev do
   let(:dev_instance) { described_class.new }
   let(:temp_dir) { Dir.mktmpdir }
   let(:original_dir) { Dir.pwd }
 
   around do |example|
-    Dir.chdir(temp_dir) do
-      example.run
+    begin
+      Dir.chdir(temp_dir) do
+        example.run
+      end
+    ensure
+      # 確実に元のディレクトリに戻る
+      begin
+        Dir.chdir(original_dir) if Dir.exist?(original_dir)
+      rescue => e
+        # ディレクトリが存在しない場合は無視
+      end
+      FileUtils.rm_rf(temp_dir) if Dir.exist?(temp_dir)
     end
-  ensure
-    Dir.chdir(original_dir)
-    FileUtils.rm_rf(temp_dir) if Dir.exist?(temp_dir)
   end
 
   describe '.description' do
@@ -70,7 +78,8 @@
         ).to_stdout
       end
 
-      it 'starts file watcher' do
+      # TODO: 一時的にスキップ - Process.kill('INT', Process.pid)がRSpec全体を中断させるため
+      xit 'starts file watcher' do
         file_watcher_called = false
         allow(dev_instance).to receive(:start_file_watcher) { file_watcher_called = true }
         allow(dev_instance).to receive(:start_server) do

From 2cdd82f933f4bff2f2640524bede845f469a06bd Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 21:47:29 +0900
Subject: [PATCH 12/13] fix: test skip problem

---
 lib/ruby_wasm_ui/cli/command.rb            |   4 +-
 lib/ruby_wasm_ui/cli/command/base.rb       |   8 +-
 lib/ruby_wasm_ui/cli/command/dev.rb        |   6 +-
 spec/ruby_wasm_ui/cli/command/base_spec.rb |  19 +--
 spec/ruby_wasm_ui/cli/command/dev_spec.rb  | 147 +++++++++++----------
 5 files changed, 94 insertions(+), 90 deletions(-)

diff --git a/lib/ruby_wasm_ui/cli/command.rb b/lib/ruby_wasm_ui/cli/command.rb
index 907535e..4b0a2a8 100644
--- a/lib/ruby_wasm_ui/cli/command.rb
+++ b/lib/ruby_wasm_ui/cli/command.rb
@@ -20,7 +20,7 @@ def self.run(argv)
 
         if command_name.nil?
           show_usage
-          exit 1
+          raise SystemExit.new(1)
         end
 
         command_class = COMMANDS[command_name]
@@ -28,7 +28,7 @@ def self.run(argv)
           puts "Unknown command: #{command_name}"
           puts ""
           show_usage
-          exit 1
+          raise SystemExit.new(1)
         end
 
         command_class.new.run(argv[1..-1])
diff --git a/lib/ruby_wasm_ui/cli/command/base.rb b/lib/ruby_wasm_ui/cli/command/base.rb
index df7e815..7113e19 100644
--- a/lib/ruby_wasm_ui/cli/command/base.rb
+++ b/lib/ruby_wasm_ui/cli/command/base.rb
@@ -50,7 +50,7 @@ def run_command(command, exit_on_error: true)
             unless exit_status.success?
               log_error("Command failed: #{command}")
               if exit_on_error
-                exit exit_status.exitstatus
+                raise SystemExit.new(exit_status.exitstatus)
               else
                 return false
               end
@@ -63,14 +63,14 @@ def run_command(command, exit_on_error: true)
         def ensure_src_directory
           unless Dir.exist?("src")
             log_error("src directory not found. Please run 'ruby-wasm-ui setup' first.")
-            exit 1
+            raise SystemExit.new(1)
           end
         end
 
         def ensure_ruby_wasm
           unless File.exist?("ruby.wasm")
             log_error("ruby.wasm not found. Please run 'ruby-wasm-ui setup' first.")
-            exit 1
+            raise SystemExit.new(1)
           end
         end
 
@@ -127,7 +127,7 @@ def check_ruby_version
 
           if major < 3 || (major == 3 && minor < 2)
             log_error("Ruby WASM requires Ruby 3.2 or higher. Current version: #{RUBY_VERSION}")
-            exit 1
+            raise SystemExit.new(1)
           end
 
           "#{major}.#{minor}"
diff --git a/lib/ruby_wasm_ui/cli/command/dev.rb b/lib/ruby_wasm_ui/cli/command/dev.rb
index 4cf0fc9..3b0be3e 100644
--- a/lib/ruby_wasm_ui/cli/command/dev.rb
+++ b/lib/ruby_wasm_ui/cli/command/dev.rb
@@ -176,7 +176,7 @@ def start_server
           trap("INT") do
             log_info("\nShutting down server...")
             cleanup
-            exit 0
+            raise SystemExit.new(0)
           end
 
           # Use Puma handler (Rack 3.0 compatible)
@@ -194,11 +194,11 @@ def start_server
           rescue LoadError => e
             log_error("Puma handler not available: #{e.message}")
             log_error("Please ensure puma gem is installed: gem install puma")
-            exit 1
+            raise SystemExit.new(1)
           end
         rescue => e
           log_error("Server error: #{e.message}")
-          exit 1
+          raise SystemExit.new(1)
         end
       end
     end
diff --git a/spec/ruby_wasm_ui/cli/command/base_spec.rb b/spec/ruby_wasm_ui/cli/command/base_spec.rb
index 687ceee..cd749f4 100644
--- a/spec/ruby_wasm_ui/cli/command/base_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/base_spec.rb
@@ -4,9 +4,7 @@
 require 'fileutils'
 require 'tmpdir'
 
-# TODO: 一時的にコメントアウト - 他のテストが実行されるか確認
-# RSpec.describe RubyWasmUi::Cli::Command::Base do
-RSpec.xdescribe RubyWasmUi::Cli::Command::Base do
+RSpec.describe RubyWasmUi::Cli::Command::Base do
   let(:base_instance) { described_class.new }
 
   describe '#run' do
@@ -233,10 +231,6 @@
     end
 
     context 'when Ruby version is less than 3.2' do
-      before do
-        allow(Kernel).to receive(:exit)
-      end
-
       context 'when Ruby version is 3.1' do
         before do
           stub_const('RUBY_VERSION', '3.1.5')
@@ -245,8 +239,9 @@
         it 'outputs error message and exits' do
           expect { base_instance.send(:check_ruby_version) }.to output(
             /\[ERROR\] Ruby WASM requires Ruby 3.2 or higher. Current version: 3.1.5/
-          ).to_stdout
-          expect(Kernel).to have_received(:exit).with(1)
+          ).to_stdout.and raise_error(SystemExit) do |error|
+            expect(error.status).to eq(1)
+          end
         end
       end
 
@@ -258,8 +253,9 @@
         it 'outputs error message and exits' do
           expect { base_instance.send(:check_ruby_version) }.to output(
             /\[ERROR\] Ruby WASM requires Ruby 3.2 or higher. Current version: 2.7.8/
-          ).to_stdout
-          expect(Kernel).to have_received(:exit).with(1)
+          ).to_stdout.and raise_error(SystemExit) do |error|
+            expect(error.status).to eq(1)
+          end
         end
       end
     end
@@ -359,5 +355,4 @@
       base_instance.send(:build_ruby_wasm, '3.4')
     end
   end
-# end
 end
diff --git a/spec/ruby_wasm_ui/cli/command/dev_spec.rb b/spec/ruby_wasm_ui/cli/command/dev_spec.rb
index 6ab4092..edcca7e 100644
--- a/spec/ruby_wasm_ui/cli/command/dev_spec.rb
+++ b/spec/ruby_wasm_ui/cli/command/dev_spec.rb
@@ -4,8 +4,7 @@
 require 'fileutils'
 require 'tmpdir'
 
-# TODO: 一時的にスキップ - 他のテストが実行されるか確認（dev_spec.rbが実行されるとRSpecが中断される）
-RSpec.xdescribe RubyWasmUi::Cli::Command::Dev do
+RSpec.describe RubyWasmUi::Cli::Command::Dev do
   let(:dev_instance) { described_class.new }
   let(:temp_dir) { Dir.mktmpdir }
   let(:original_dir) { Dir.pwd }
@@ -78,22 +77,20 @@
         ).to_stdout
       end
 
-      # TODO: 一時的にスキップ - Process.kill('INT', Process.pid)がRSpec全体を中断させるため
-      xit 'starts file watcher' do
+      it 'starts file watcher' do
         file_watcher_called = false
-        allow(dev_instance).to receive(:start_file_watcher) { file_watcher_called = true }
-        allow(dev_instance).to receive(:start_server) do
-          # Simulate blocking server
-          sleep 0.01
-        end
         # Allow Thread.new to actually create threads so start_file_watcher gets called
         allow(Thread).to receive(:new).and_call_original
-        Thread.new { sleep 0.02; Process.kill('INT', Process.pid) }
-        begin
-          dev_instance.run([])
-        rescue SystemExit
-          # Expected when server is killed
+        allow(dev_instance).to receive(:start_file_watcher) do
+          file_watcher_called = true
+        end
+        # Mock start_server to block briefly to allow thread to execute
+        allow(dev_instance).to receive(:start_server) do
+          sleep 0.1  # Give thread time to execute
         end
+
+        dev_instance.run([])
+
         expect(file_watcher_called).to be true
       end
 
@@ -205,10 +202,10 @@
         dev_instance.send(:start_file_watcher)
         callback = callback_container[:callback]
         expect(callback).not_to be_nil
-        
+
         # Allow Thread.new to create actual threads for the debounce logic
         allow(Thread).to receive(:new).and_call_original
-        
+
         callback.call(['src/app.rb'], [], [])
         sleep 0.6 # Wait for debounce
         expect(dev_instance).to have_received(:build)
@@ -218,10 +215,10 @@
         dev_instance.send(:start_file_watcher)
         callback = callback_container[:callback]
         expect(callback).not_to be_nil
-        
+
         # Allow Thread.new to create actual threads for the debounce logic
         allow(Thread).to receive(:new).and_call_original
-        
+
         callback.call(['src/app.rb.swp'], [], [])
         sleep 0.6
         expect(dev_instance).not_to have_received(:build)
@@ -252,64 +249,74 @@ def self.run(app, options = {})
 
     before do
       FileUtils.mkdir_p('src')
-      stub_const('Rack::Handler::Puma', puma_handler_class)
-      allow(Kernel).to receive(:require).with('rack/handler/puma')
     end
 
-    it 'outputs server start message' do
-      allow(Rack::Handler::Puma).to receive(:run)
-      expect { dev_instance.send(:start_server) }.to output(
-        /Starting development server on http:\/\/localhost:8080/
-      ).to_stdout
-    end
+    context 'when Puma handler is available' do
+      before do
+        stub_const('Rack::Handler::Puma', puma_handler_class)
+        # Mock require to prevent LoadError for rack/handler/puma
+        allow(dev_instance).to receive(:require).with('rack/handler/puma').and_return(true)
+        # Prevent browser from opening in all tests by default
+        allow(dev_instance).to receive(:open_browser)
+        # Prevent Thread.new from creating actual threads by default
+        allow(Thread).to receive(:new).and_return(instance_double(Thread))
+      end
 
-    it 'outputs instructions message' do
-      allow(Rack::Handler::Puma).to receive(:run)
-      expect { dev_instance.send(:start_server) }.to output(
-        /Press Ctrl+C to stop/
-      ).to_stdout
-    end
+      it 'outputs server start message' do
+        allow(Rack::Handler::Puma).to receive(:run)
+        expect { dev_instance.send(:start_server) }.to output(
+          a_string_including('Starting development server on http://localhost:8080')
+        ).to_stdout
+      end
 
-    it 'starts Puma server' do
-      expect(Rack::Handler::Puma).to receive(:run).with(
-        anything,
-        Port: 8080,
-        Host: '0.0.0.0'
-      )
-      dev_instance.send(:start_server)
-    end
+      it 'outputs instructions message' do
+        allow(Rack::Handler::Puma).to receive(:run)
+        expect { dev_instance.send(:start_server) }.to output(
+          a_string_including('Press Ctrl+C to stop')
+        ).to_stdout
+      end
 
-    it 'outputs handler info message' do
-      allow(Rack::Handler::Puma).to receive(:run)
-      expect { dev_instance.send(:start_server) }.to output(
-        /Using handler: puma/
-      ).to_stdout
-    end
+        it 'starts Puma server' do
+        expect(Rack::Handler::Puma).to receive(:run).with(
+          anything,
+          Port: 8080,
+          Host: '0.0.0.0'
+        )
+        dev_instance.send(:start_server)
+      end
+
+      it 'outputs handler info message' do
+        allow(Rack::Handler::Puma).to receive(:run)
+        expect { dev_instance.send(:start_server) }.to output(
+          a_string_including('Using handler: puma')
+        ).to_stdout
+      end
+
+        it 'opens browser after server starts' do
+        allow(Rack::Handler::Puma).to receive(:run)
+        browser_thread_called = false
 
-    it 'opens browser after server starts' do
-      allow(Rack::Handler::Puma).to receive(:run)
-      browser_thread_called = false
-      
-      allow(Thread).to receive(:new) do |&block|
-        if block
-          browser_thread_called = true
-          # Execute block immediately for testing (without sleep)
-          allow(Kernel).to receive(:sleep)
-          block.call
+        allow(Thread).to receive(:new) do |&block|
+          if block
+            browser_thread_called = true
+            # Execute block immediately for testing (without sleep)
+            allow(Kernel).to receive(:sleep)
+            block.call
+          end
+          instance_double(Thread)
         end
-        instance_double(Thread)
-      end
-      
-      expect(dev_instance).to receive(:open_browser).with('http://localhost:8080/src/index.html')
-      
-      dev_instance.send(:start_server)
-      
-      expect(browser_thread_called).to be true
-    end
+
+        expect(dev_instance).to receive(:open_browser).with('http://localhost:8080/src/index.html').and_return(nil)
+
+        dev_instance.send(:start_server)
+
+        expect(browser_thread_called).to be true
+        end
+      end
 
     context 'when Puma handler is not available' do
       before do
-        allow(Kernel).to receive(:require).with('rack/handler/puma').and_raise(LoadError.new('cannot load such file'))
+        allow(dev_instance).to receive(:require).with('rack/handler/puma').and_raise(LoadError.new('cannot load such file'))
       end
 
       it 'outputs error message' do
@@ -327,6 +334,8 @@ def self.run(app, options = {})
 
     context 'when server raises an error' do
       before do
+        stub_const('Rack::Handler::Puma', puma_handler_class)
+        allow(dev_instance).to receive(:require).with('rack/handler/puma').and_return(true)
         allow(Rack::Handler::Puma).to receive(:run).and_raise(StandardError.new('Server error'))
       end
 
@@ -349,7 +358,7 @@ def self.run(app, options = {})
       end
 
       it 'calls open command' do
-        expect(dev_instance).to receive(:system).with('open', 'http://localhost:8080/src/index.html')
+        expect(dev_instance).to receive(:system).with('open', 'http://localhost:8080/src/index.html').and_return(true)
         dev_instance.send(:open_browser, 'http://localhost:8080/src/index.html')
       end
 
@@ -372,7 +381,7 @@ def self.run(app, options = {})
       end
 
       it 'calls xdg-open command' do
-        expect(dev_instance).to receive(:system).with('xdg-open', 'http://localhost:8080/src/index.html')
+        expect(dev_instance).to receive(:system).with('xdg-open', 'http://localhost:8080/src/index.html').and_return(true)
         dev_instance.send(:open_browser, 'http://localhost:8080/src/index.html')
       end
     end
@@ -383,7 +392,7 @@ def self.run(app, options = {})
       end
 
       it 'calls start command' do
-        expect(dev_instance).to receive(:system).with('start', 'http://localhost:8080/src/index.html')
+        expect(dev_instance).to receive(:system).with('start', 'http://localhost:8080/src/index.html').and_return(true)
         dev_instance.send(:open_browser, 'http://localhost:8080/src/index.html')
       end
     end

From ea5b14f299f2db0b8e16b50d5a65620cfbf37772 Mon Sep 17 00:00:00 2001
From: t0yohei <inuneko690121@gmail.com>
Date: Mon, 8 Dec 2025 22:59:10 +0900
Subject: [PATCH 13/13] update: Build only runtime modules

---
 packages/npm-packages/runtime/rollup.config.mjs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/npm-packages/runtime/rollup.config.mjs b/packages/npm-packages/runtime/rollup.config.mjs
index ba92262..b45b8c9 100644
--- a/packages/npm-packages/runtime/rollup.config.mjs
+++ b/packages/npm-packages/runtime/rollup.config.mjs
@@ -18,7 +18,7 @@ const __dirname = dirname(fileURLToPath(import.meta.url));
 
 // Find all Ruby files in ruby_wasm_ui directory
 const rubyFiles = glob
-  .sync("src/ruby_wasm_ui/**/*.rb")
+  .sync("src/ruby_wasm_ui/runtime/**/*.rb")
   .map((file) => file.replace("src/", ""))
   .sort((a, b) => {
     // Files in root directory should be loaded first