Add debug gem for development and implement scaffold generator tests

Author: raphox

Gemfile

@@ -9,3 +9,7 @@ gem "minitest", "~> 5.0"
 gem "rake", "~> 13.0"
 gem "rubocop", "~> 1.21"
 gem "tty-prompt", "~> 0.23.1"
+
+group :development do
+  gem "debug", platforms: %i[mri windows], require: "debug/prelude"
+end

Gemfile.lock

@@ -90,6 +90,9 @@ GEM
     connection_pool (2.4.1)
     crass (1.0.6)
     date (3.3.4)
+    debug (1.8.0)
+      irb (>= 1.5.0)
+      reline (>= 0.3.1)
     drb (2.2.0)
       ruby2_keywords
     erubi (1.12.0)
@@ -228,6 +231,7 @@ PLATFORMS
   x86_64-linux
 
 DEPENDENCIES
+  debug
   minitest (~> 5.0)
   next_rails_scaffold!
   rake (~> 13.0)

lib/generators/next_rails_scaffold/node_package_manager.rb

@@ -0,0 +1,98 @@
+# frozen_string_literal: true
+
+require "open3"
+require "tty-prompt"
+
+module NextRailsScaffold
+  module Generators
+    NodePackageManagerStruct = Struct.new(:fetch, :run, :add, :lock_file, :version) do
+      def to_s = run.split.first
+
+      def available?
+        version.present?
+      end
+
+      def version
+        @version ||= NodePackageManager.get_version(to_s)
+      end
+    end
+
+    NODE_REQUIRED_VERSION = ENV.fetch("NODE_REQUIRED_VERSION", ">= 18.20")
+    NEXT_VERSION = ENV.fetch("NEXT_VERSION", "15.1.6")
+
+    PACKAGE_MANAGERS = {
+      "npm" => NodePackageManagerStruct.new("npx", "npm run", "npm install", "package-lock.json"),
+      "yarn" => NodePackageManagerStruct.new("npx", "yarn", "yarn add", "yarn.lock"),
+      "pnpm" => NodePackageManagerStruct.new("pnpm dlx", "pnpm", "pnpm add", "pnpm-lock.yaml"),
+      "bun" => NodePackageManagerStruct.new("bunx", "bun run", "bun add", "bun.lock.json")
+    }.freeze
+
+    class NodePackageManager
+      attr_reader :selected_package_manager
+
+      def self.get_version(command)
+        Open3.capture3(command, "--version").first.gsub(/[^0-9.]/, "")
+      rescue Errno::ENOENT
+        nil
+      end
+
+      def initialize(shell)
+        @prompt = TTY::Prompt.new
+        @shell = shell
+      end
+
+      def check_node!
+        node_version = self.class.get_version("node")
+
+        return if Gem::Dependency.new("", NODE_REQUIRED_VERSION).match?("", node_version)
+
+        raise node_version ? "Your Node version is '#{node_version}'" : "Node not found"
+      end
+
+      def check_pm_version!
+        package_manager = @shell.base.options[:package_manager]
+
+        unless package_manager
+          PACKAGE_MANAGERS.each do |manager, details|
+            if File.exist?(details.lock_file)
+              package_manager = manager
+              break
+            end
+          end
+        end
+
+        until PACKAGE_MANAGERS.keys.include?(package_manager)
+          raise "Invalid package manager" unless package_manager.nil?
+
+          package_manager = @prompt.select(
+            "Which package manager do you want to use?",
+            PACKAGE_MANAGERS.keys.map { |pm| { name: pm, value: pm, disabled: !PACKAGE_MANAGERS[pm].available? } }
+          )
+        end
+
+        @selected_package_manager = PACKAGE_MANAGERS[package_manager]
+      end
+
+      def create_next_app!
+        return if File.exist?("package.json")
+
+        system(
+          "#{selected_package_manager.fetch} create-next-app@#{NEXT_VERSION} . --use-#{selected_package_manager} " \
+          "--no-app --src-dir --import-alias \"@/*\" #{Rails.env.test? ? "--yes" : ""}"
+        )
+
+        if selected_package_manager.to_s == "yarn" &&
+           Gem::Dependency.new("", ">= 2.0").match?("", selected_package_manager.version)
+          system("yarn config set nodeLinker node-modules")
+        end
+      end
+
+      def install_hygen!
+        return if Dir.exist?("_templates")
+
+        system("#{selected_package_manager.add} -D hygen hygen-add")
+        system("#{selected_package_manager.fetch} hygen-add next-rails-scaffold")
+      end
+    end
+  end
+end

lib/generators/next_rails_scaffold/scaffold_generator.rb

@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+require "rails/generators/rails/scaffold/scaffold_generator"
+require_relative "node_package_manager"
+
+module NextRailsScaffold
+  module Generators
+    class ScaffoldGenerator < Rails::Generators::ScaffoldGenerator
+      include ::NextRailsScaffold::Actions
+
+      source_root File.expand_path("templates", __dir__)
+
+      argument :attributes, type: :array, default: [], banner: "field:type field:type"
+      class_option :package_manager, type: :string, desc: "Package manager to use for frontend project"
+      class_option :skip_build, type: :boolean, default: false, desc: "Skip running Next.js build"
+      class_option :skip_routes, type: :boolean, default: false, desc: "Skip adding resources to routes.rb"
+
+      attr_accessor :selected_package_manager
+
+      def initialize(args, *options) # :nodoc:
+        super
+        self.attributes = shell.base.attributes
+      end
+
+      def add_resource_route
+        return if options[:actions].present? || options[:skip_routes]
+
+        route "resources :#{file_name.pluralize}", namespace: regular_class_path, scope: "/api"
+      end
+
+      def create_root_folder
+        empty_directory "frontend"
+      end
+
+      # Check Javascript dependencies and create a new Next.js project. Install the the useful packages and create the
+      # scaffold code for frontend application.
+      def create_frontend_project
+        return say_status :remove, "skip frontend folder", :yellow if shell.base.behavior == :revoke
+
+        append_gitignore!
+
+        node_package_manager = NodePackageManager.new(shell)
+
+        inside("frontend") do
+          node_package_manager.check_node!
+          node_package_manager.check_pm_version!
+          node_package_manager.create_next_app!
+          node_package_manager.install_hygen!
+
+          return if Rails.env.test?
+
+          selected_package_manager = node_package_manager.selected_package_manager
+          language = File.exist?("tsconfig.json") ? "typescript" : "javascript"
+
+          run("#{selected_package_manager.fetch} hygen scaffold #{language} #{name} #{mapped_attributes.join(" ")}")
+          if !options[:skip_build] && !@prompt.no?("Do you want to build your Next.js project?")
+            run("#{selected_package_manager.run} build")
+          end
+        end
+      end
+
+      private
+
+      def append_gitignore!
+        path = File.join(destination_root, ".gitignore")
+
+        return unless File.exist?(path)
+
+        rows = <<~HEREDOC
+
+          # Ignoring node modules for Rails and Next.js projects
+          node_modules/
+        HEREDOC
+
+        append_to_file path, rows
+      end
+
+      def mapped_attributes
+        attributes.map { |attr| "#{attr.name}:#{attr.type}" }
+      end
+    end
+  end
+end