Add Rails request specs with ActiveRecord and fixtures

.github/workflows/main.yml

@@ -8,12 +8,17 @@ on:
 jobs:
   build:
     runs-on: ubuntu-latest
+    env:
+      FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true
     name: Ruby ${{ matrix.ruby }}
     strategy:
+      fail-fast: false
       matrix:
         ruby:
           - "3.2"
           - "3.3"
+          - "3.4"
+          - "4.0"
           - "ruby-head"
 
     steps:

.gitignore

@@ -16,3 +16,10 @@ Gemfile.lock
 
 # MacOS
 .DS_Store
+
+# Dummy app artifacts
+spec/dummy/log/
+spec/dummy/tmp/
+
+# Claude
+.claude/settings.local.json

.rubocop_todo.yml

@@ -1,12 +1,17 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2025-11-17 23:28:22 UTC using RuboCop version 1.81.7.
+# on 2026-01-25 10:40:25 UTC using RuboCop version 1.81.7.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
 # versions of RuboCop, may require this file to be generated again.
 
-# Offense count: 2
+# Offense count: 1
+# Configuration parameters: CountComments, CountAsOne, AllowedMethods, AllowedPatterns.
+Metrics/MethodLength:
+  Max: 12
+
+# Offense count: 6
 # Configuration parameters: CountAsOne.
 RSpec/ExampleLength:
   Max: 14

AGENTS.md

@@ -0,0 +1,5 @@
+# Agents
+
+## Style
+
+- Always use Ruby keyword argument shorthand (e.g., `super(**kwargs, json:)` not `super(**kwargs, json: json)`).

Gemfile

@@ -7,7 +7,10 @@ gemspec
 
 gem "rake", "~> 13.0"
 
+gem "rails", ">= 7.2"
+
 gem "rspec", "~> 3.0"
+gem "rspec-rails", "~> 7.0"
 
 gem "rubocop", "~> 1.21"
 gem "rubocop-rspec", require: false
@@ -18,5 +21,7 @@ gem "undercover"
 
 gem "pry"
 
+gem "sqlite3"
+
 gem "gem-release", require: false
 gem "solargraph", require: false

lib/transmutation/serialization/rendering.rb

@@ -4,11 +4,26 @@ module Transmutation
   module Serialization
     module Rendering
       # Serializes the value of the `json` parameter before calling the existing render method.
-      def render(json: nil, serialize: true, namespace: nil, serializer: nil, max_depth: 1, **args)
-        return super(**args) unless json
-        return super(**args, json:) unless serialize
+      #
+      # Handles both Rails-style hash arguments (e.g., from send_data) and keyword arguments.
+      def render(options = nil, **kwargs)
+        # Handle Rails-style positional hash argument (e.g., from send_data calling render(body: data))
+        if options.is_a?(Hash)
+          return super(options) unless options.key?(:json)
 
-        super(**args, json: serialize(json, namespace:, serializer:, max_depth:))
+          kwargs = options.merge(kwargs)
+        end
+
+        json = kwargs.delete(:json)
+        should_serialize = kwargs.key?(:serialize) ? kwargs.delete(:serialize) : true
+        namespace = kwargs.delete(:namespace)
+        serializer = kwargs.delete(:serializer)
+        max_depth = kwargs.delete(:max_depth) || Transmutation.max_depth
+
+        return super(**kwargs) unless json
+        return super(**kwargs, json:) unless should_serialize
+
+        super(**kwargs, json: serialize(json, namespace:, serializer:, max_depth:))
       end
     end
   end

spec/system/dummy/controllers/api/application_controller.rb → spec/dummy/app/controllers/api/application_controller.rb

@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 module Api
-  class ApplicationController < BaseController
+  class ApplicationController < ::ApplicationController
     include Transmutation::Serialization
   end
 end

spec/system/dummy/controllers/api/v1/health_controller.rb → spec/dummy/app/controllers/api/v1/health_controller.rb

@@ -4,11 +4,11 @@ module Api
   module V1
     class HealthController < Api::ApplicationController
       def index
-        render(json: { ok: true })
+        render json: { ok: true }
       end
 
       def download
-        send_data("binary data content", filename: "report.txt", type: "text/plain")
+        send_data "binary data content", filename: "report.txt", type: "text/plain"
       end
     end
   end

spec/system/dummy/controllers/api/v1/posts_controller.rb → spec/dummy/app/controllers/api/v1/posts_controller.rb

@@ -5,13 +5,11 @@ module V1
     class PostsController < Api::ApplicationController
       def index
         posts = Post.all
-
         render json: posts
       end
 
-      def show(id)
-        post = Post.find(id)
-
+      def show
+        post = Post.find(params[:id])
         render json: post, namespace: "Detailed"
       end
     end

spec/system/dummy/controllers/api/v1/products_controller.rb → spec/dummy/app/controllers/api/v1/products_controller.rb

@@ -3,10 +3,9 @@
 module Api
   module V1
     class ProductsController < Api::ApplicationController
-      def show(id)
-        post = Product.find(id)
-
-        render json: post
+      def show
+        product = Product.find(params[:id])
+        render json: product
       end
     end
   end

spec/system/dummy/controllers/api/v1/users_controller.rb → spec/dummy/app/controllers/api/v1/users_controller.rb

@@ -5,13 +5,11 @@ module V1
     class UsersController < Api::ApplicationController
       def index
         users = User.all
-
         render json: users
       end
 
-      def show(id)
-        user = User.find(id)
-
+      def show
+        user = User.find(params[:id])
         render json: user, serializer: "Detailed::UserSerializer"
       end
     end

spec/dummy/app/controllers/application_controller.rb

@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+class ApplicationController < ActionController::API
+end

spec/dummy/app/models/comment.rb

@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+class Comment < ActiveRecord::Base
+  belongs_to :user, optional: true
+end

spec/dummy/app/models/post.rb

@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+class Post < ActiveRecord::Base
+  belongs_to :user, optional: true
+end

spec/dummy/app/models/product.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class Product < ActiveRecord::Base
+  def price
+    Money.new(price_subunit, price_currency)
+  end
+end

spec/dummy/app/models/user.rb

@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+class User < ActiveRecord::Base
+  has_many :posts
+  has_many :comments
+end

spec/dummy/config/application.rb

@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+require_relative "boot"
+
+require "rails"
+require "active_record/railtie"
+require "action_controller/railtie"
+
+Bundler.require(*Rails.groups)
+
+require "transmutation"
+
+module Dummy
+  class Application < Rails::Application
+    config.root = File.expand_path("..", __dir__)
+
+    config.load_defaults Rails::VERSION::STRING.to_f
+
+    config.autoload_paths << config.root.join("app/serializers")
+
+    config.api_only = true
+    config.eager_load = false
+  end
+end

spec/dummy/config/boot.rb

@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../../../Gemfile", __dir__)
+
+require "bundler/setup" if File.exist?(ENV["BUNDLE_GEMFILE"])
+$LOAD_PATH.unshift File.expand_path("../../../lib", __dir__)

spec/dummy/config/database.yml

@@ -0,0 +1,3 @@
+test:
+  adapter: sqlite3
+  database: ":memory:"

spec/dummy/config/environment.rb

@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+require_relative "application"
+
+Rails.application.initialize!

spec/dummy/config/environments/test.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+Rails.application.configure do
+  config.eager_load = false
+  config.consider_all_requests_local = true
+  config.action_controller.perform_caching = false
+  config.action_controller.allow_forgery_protection = false
+  config.active_support.deprecation = :stderr
+end

spec/dummy/config/routes.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+Rails.application.routes.draw do
+  namespace :api do
+    namespace :v1 do
+      resources :users, only: %i[index show]
+      resources :posts, only: %i[index show]
+      resources :products, only: [:show]
+      resources :health, only: [:index] do
+        collection do
+          get :download
+        end
+      end
+    end
+  end
+end

spec/dummy/db/schema.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+ActiveRecord::Schema.define(version: 0) do
+  create_table :users, force: true do |t|
+    t.string :first_name, null: false
+    t.string :last_name, null: false
+  end
+
+  create_table :posts, force: true do |t|
+    t.string :title, null: false
+    t.text :body, null: false
+    t.references :user, foreign_key: true
+    t.datetime :published_at
+  end
+
+  create_table :comments, force: true do |t|
+    t.text :body, null: false
+    t.references :user, foreign_key: true
+  end
+
+  create_table :products, force: true do |t|
+    t.string :name, null: false
+    t.string :description
+    t.integer :price_subunit, null: false
+    t.string :price_currency, null: false
+  end
+end

spec/dummy/test/fixtures/comments.yml

@@ -0,0 +1,14 @@
+first_comment:
+  id: 1
+  body: "First!"
+  user_id: 1
+
+second_comment:
+  id: 2
+  body: "Second!"
+  user_id: 2
+
+third_comment:
+  id: 3
+  body: "Third!"
+  user_id: 1

spec/dummy/test/fixtures/posts.yml

@@ -0,0 +1,20 @@
+first_post:
+  id: 1
+  title: First post
+  body: "First!"
+  user_id: 1
+  published_at: 2025-01-01 00:00:00
+
+second_post:
+  id: 2
+  title: How does this work?
+  body: body
+  user_id: 2
+  published_at: 2025-01-01 00:00:00
+
+third_post:
+  id: 3
+  title: "Second post!?"
+  body: "Nope..."
+  user_id: 1
+  published_at: null

spec/dummy/test/fixtures/products.yml

@@ -0,0 +1,6 @@
+shoes:
+  id: 1
+  name: Shoes
+  description: A pair of shoes
+  price_subunit: 1000
+  price_currency: GBP

spec/dummy/test/fixtures/users.yml

@@ -0,0 +1,19 @@
+john:
+  id: 1
+  first_name: John
+  last_name: Doe
+
+jane:
+  id: 2
+  first_name: Jane
+  last_name: Doe
+
+adam:
+  id: 3
+  first_name: Adam
+  last_name: Smith
+
+eve:
+  id: 4
+  first_name: Eve
+  last_name: Smith

spec/lib/transmutation/serialization_spec.rb

@@ -180,6 +180,10 @@ def initialize(id:)
         Transmutation.max_depth = 2
       end
 
+      after do
+        Transmutation.max_depth = 1
+      end
+
       it "returns the maximum depth of the serializer" do
         expect(Transmutation.max_depth).to eq(2)
       end