Move React/Shakapacker version compatibility to generator smoke tests

This moves React and Shakapacker version compatibility testing from
spec/dummy to the generator smoke tests, as suggested in PR #2114 review.

Changes:
- Update spec/dummy to always use latest React 19 and Shakapacker 9.4.0
- Add minimum version example apps (basic-minimum, basic-server-rendering-minimum)
  that use React 18.0.0 and Shakapacker 8.2.0
- Add ExampleType.minimum_versions flag to support version-specific examples
- Add rake tasks for filtered testing:
  - run_rspec:shakapacker_examples_latest (for latest versions only)
  - run_rspec:shakapacker_examples_minimum (for minimum versions only)
- Simplify script/convert to only handle Node.js tooling compatibility
  (removed React/Shakapacker version modifications)
- Update CI workflows to run appropriate examples per dependency level

Benefits:
- Clearer separation: spec/dummy tests latest, generators test compatibility
- Simpler CI configuration for integration tests
- Better reflects real-world usage patterns

Closes #2123

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: justin808

.github/workflows/examples.yml

@@ -137,7 +137,7 @@ jobs:
           echo "Node version: "; node -v
           echo "pnpm version: "; pnpm --version
           echo "Bundler version: "; bundle --version
-      - name: run conversion script to support shakapacker v6
+      - name: Run conversion script for older Node compatibility
         if: matrix.dependency-level == 'minimum'
         run: script/convert
       - name: Save root ruby gems to cache
@@ -180,8 +180,12 @@ jobs:
       - name: Set packer version environment variable
         run: |
           echo "CI_DEPENDENCY_LEVEL=${{ matrix.dependency-level }}" >> $GITHUB_ENV
-      - name: Main CI
-        run: cd react_on_rails && bundle exec rake run_rspec:shakapacker_examples
+      - name: Main CI - Latest version examples
+        if: matrix.dependency-level == 'latest'
+        run: cd react_on_rails && bundle exec rake run_rspec:shakapacker_examples_latest
+      - name: Main CI - Minimum version examples
+        if: matrix.dependency-level == 'minimum'
+        run: cd react_on_rails && bundle exec rake run_rspec:shakapacker_examples_minimum
       - name: Store test results
         uses: actions/upload-artifact@v4
         with:

.github/workflows/integration-tests.yml

@@ -140,7 +140,7 @@ jobs:
           echo "Node version: "; node -v
           echo "pnpm version: "; pnpm --version
           echo "Bundler version: "; bundle --version
-      - name: run conversion script to support shakapacker v6
+      - name: Run conversion script for older Node compatibility
         if: matrix.dependency-level == 'minimum'
         run: script/convert
       - name: Install Node modules with pnpm for renderer package
@@ -229,7 +229,7 @@ jobs:
           echo "Node version: "; node -v
           echo "pnpm version: "; pnpm --version
           echo "Bundler version: "; bundle --version
-      - name: run conversion script to support shakapacker v6
+      - name: Run conversion script for older Node compatibility
         if: matrix.dependency-level == 'minimum'
         run: script/convert
       - name: Save root ruby gems to cache

package.json

@@ -55,8 +55,8 @@
     "prettier": "^3.5.2",
     "prop-types": "^15.8.1",
     "publint": "^0.3.4",
-    "react": "18.0.0",
-    "react-dom": "18.0.0",
+    "react": "^19.0.0",
+    "react-dom": "^19.0.0",
     "react-on-rails-rsc": "19.0.2",
     "redux": "^4.2.1",
     "stylelint": "^16.14.0",

react_on_rails/rakelib/example_type.rb

@@ -13,12 +13,17 @@ def self.all
         @all ||= { shakapacker_examples: [] }
       end
 
-      attr_reader :packer_type, :name, :generator_options
+      # Minimum supported versions for compatibility testing
+      MINIMUM_REACT_VERSION = "18.0.0"
+      MINIMUM_SHAKAPACKER_VERSION = "8.2.0"
 
-      def initialize(packer_type: nil, name: nil, generator_options: nil)
+      attr_reader :packer_type, :name, :generator_options, :minimum_versions
+
+      def initialize(packer_type: nil, name: nil, generator_options: nil, minimum_versions: false)
         @packer_type = packer_type
         @name = name
         @generator_options = generator_options
+        @minimum_versions = minimum_versions
         self.class.all[packer_type.to_sym] << self
       end
 

react_on_rails/rakelib/examples_config.yml

@@ -7,3 +7,10 @@ example_type_data:
     generator_options: --redux
   - name: redux-server-rendering
     generator_options: --redux --example-server-rendering
+  # Minimum version compatibility tests - tests React 18 and Shakapacker 8.2.0
+  - name: basic-minimum
+    generator_options: ''
+    minimum_versions: true
+  - name: basic-server-rendering-minimum
+    generator_options: --example-server-rendering
+    minimum_versions: true

react_on_rails/rakelib/run_rspec.rake

@@ -90,6 +90,25 @@ namespace :run_rspec do
     ExampleType.all[:shakapacker_examples].each { |example_type| Rake::Task[example_type.rspec_task_name].invoke }
   end
 
+  # Helper methods for filtering examples
+  def latest_examples
+    ExampleType.all[:shakapacker_examples].reject(&:minimum_versions)
+  end
+
+  def minimum_examples
+    ExampleType.all[:shakapacker_examples].select(&:minimum_versions)
+  end
+
+  desc "Runs Rspec for latest version example apps only (excludes minimum version tests)"
+  task shakapacker_examples_latest: latest_examples.map(&:gen_task_name) do
+    latest_examples.each { |example_type| Rake::Task[example_type.rspec_task_name].invoke }
+  end
+
+  desc "Runs Rspec for minimum version example apps only (React 18, Shakapacker 8.2.0)"
+  task shakapacker_examples_minimum: minimum_examples.map(&:gen_task_name) do
+    minimum_examples.each { |example_type| Rake::Task[example_type.rspec_task_name].invoke }
+  end
+
   Coveralls::RakeTask.new if ENV["USE_COVERALLS"] == "TRUE"
 
   desc "run all tests no examples"

react_on_rails/rakelib/shakapacker_examples.rake

@@ -8,13 +8,40 @@
 require "yaml"
 require "rails/version"
 require "pathname"
+require "json"
 
 require_relative "example_type"
 require_relative "task_helpers"
 
 namespace :shakapacker_examples do # rubocop:disable Metrics/BlockLength
   include ReactOnRails::TaskHelpers
 
+  # Updates package.json to use minimum supported versions for compatibility testing
+  def apply_minimum_versions(dir)
+    package_json_path = File.join(dir, "package.json")
+    return unless File.exist?(package_json_path)
+
+    package_json = JSON.parse(File.read(package_json_path))
+
+    # Update React versions to minimum supported
+    if package_json["dependencies"]
+      package_json["dependencies"]["react"] = ExampleType::MINIMUM_REACT_VERSION
+      package_json["dependencies"]["react-dom"] = ExampleType::MINIMUM_REACT_VERSION
+    end
+
+    # Update Shakapacker to minimum supported version
+    if package_json["devDependencies"]&.key?("shakapacker")
+      package_json["devDependencies"]["shakapacker"] = ExampleType::MINIMUM_SHAKAPACKER_VERSION
+    elsif package_json["dependencies"]&.key?("shakapacker")
+      package_json["dependencies"]["shakapacker"] = ExampleType::MINIMUM_SHAKAPACKER_VERSION
+    end
+
+    File.write(package_json_path, "#{JSON.pretty_generate(package_json)}\n")
+    puts "  Updated package.json with minimum versions:"
+    puts "    React: #{ExampleType::MINIMUM_REACT_VERSION}"
+    puts "    Shakapacker: #{ExampleType::MINIMUM_SHAKAPACKER_VERSION}"
+  end
+
   # Define tasks for each example type
   ExampleType.all[:shakapacker_examples].each do |example_type|
     relative_gem_root = Pathname(gem_root).relative_path_from(Pathname(example_type.dir))
@@ -46,6 +73,10 @@ namespace :shakapacker_examples do # rubocop:disable Metrics/BlockLength
         "REACT_ON_RAILS_SKIP_VALIDATION=true #{cmd}"
       end
       sh_in_dir(example_type.dir, generator_commands)
+
+      # Apply minimum versions for compatibility testing examples
+      apply_minimum_versions(example_type.dir) if example_type.minimum_versions
+
       sh_in_dir(example_type.dir, "npm install")
       # Generate the component packs after running the generator to ensure all
       # auto-bundled components have corresponding pack files created

react_on_rails/spec/dummy/package.json

@@ -18,8 +18,8 @@
     "node-libs-browser": "^2.2.1",
     "null-loader": "^4.0.0",
     "prop-types": "^15.7.2",
-    "react": "18.0.0",
-    "react-dom": "18.0.0",
+    "react": "^19.0.0",
+    "react-dom": "^19.0.0",
     "react-helmet": "^6.1.0",
     "react-on-rails": "link:.yalc/react-on-rails",
     "react-redux": "^8.0.2",

script/convert

@@ -1,6 +1,14 @@
 #!/usr/bin/env ruby
 # frozen_string_literal: true
 
+# This script converts the codebase to use minimum supported dependency versions.
+# It's run during CI when testing the "minimum" dependency matrix to ensure
+# backward compatibility.
+#
+# React/Shakapacker version compatibility is now tested through generator smoke tests
+# (see examples_config.yml for minimum version examples like basic-minimum).
+# This script only handles Node.js/tooling compatibility and Pro package test adjustments.
+
 def gsub_file_content(path, old_content, new_content)
   path = File.expand_path(path, __dir__)
 
@@ -17,19 +25,6 @@ def gsub_file_content(path, old_content, new_content)
   File.binwrite(path, content)
 end
 
-def move(old_path, new_path)
-  old_path = File.expand_path(old_path, __dir__)
-  new_path = File.expand_path(new_path, __dir__)
-  File.rename(old_path, new_path)
-end
-
-# Keep shakapacker.yml since we're using Shakapacker 8+
-# move("../react_on_rails/spec/dummy/config/shakapacker.yml", "../react_on_rails/spec/dummy/config/webpacker.yml")
-
-# Shakapacker - use version with async script loading support (8.2.0+)
-gsub_file_content("../react_on_rails/Gemfile.development_dependencies", /gem "shakapacker", "[^"]*"/, 'gem "shakapacker", "8.2.0"')
-gsub_file_content("../react_on_rails/spec/dummy/package.json", /"shakapacker": "[^"]*",/, '"shakapacker": "8.2.0",')
-
 # The below packages don't work on the oldest supported Node version and aren't needed there anyway
 # Note: All dev dependencies remain in root package.json even after workspace migration
 gsub_file_content("../package.json", /"[^"]*eslint[^"]*": "[^"]*",?/, "")
@@ -42,11 +37,7 @@ gsub_file_content("../package.json", %r{"@testing-library/[^"]*": "[^"]*",}, "")
 # Clean up any trailing commas before closing braces
 gsub_file_content("../package.json", /,(\s*})/, "\\1")
 
-# Switch to minimum supported React version (React 18 since we removed PropTypes)
-gsub_file_content("../package.json", /"react": "[^"]*",/, '"react": "18.0.0",')
-gsub_file_content("../package.json", /"react-dom": "[^"]*",/, '"react-dom": "18.0.0",')
-gsub_file_content("../react_on_rails/spec/dummy/package.json", /"react": "[^"]*",/, '"react": "18.0.0",')
-gsub_file_content("../react_on_rails/spec/dummy/package.json", /"react-dom": "[^"]*",/, '"react-dom": "18.0.0",')
+# Pro package: Skip RSC tests on React 18 since RSC requires React 19
 gsub_file_content(
   "../packages/react-on-rails-pro/package.json",
   /"test:non-rsc": "(?:\\"|[^"])*",/,