feat: Add support for ActiveModel::Attributes instance and class

gemfiles/mongoid_7.0.gemfile

@@ -5,11 +5,11 @@ source "https://rubygems.org"
 gem "appraisal", git: "https://github.com/thoughtbot/appraisal.git", branch: :main
 gem "bigdecimal"
 gem "fakefs", "~> 1.2"
-gem "mongoid", "~> 7.0.0"
 gem "nokogiri", "~> 1.10"
 gem "pry"
 gem "rspec", "~> 3.9"
 gem "rubocop", "~> 1.20"
 gem "rubocop-rspec", "~> 2.4"
+gem "mongoid", "~> 7.0.0"
 
 gemspec path: "../"

gemfiles/mongoid_8.0.gemfile

@@ -5,11 +5,11 @@ source "https://rubygems.org"
 gem "appraisal", git: "https://github.com/thoughtbot/appraisal.git", branch: :main
 gem "bigdecimal"
 gem "fakefs", "~> 1.2"
-gem "mongoid", "~> 8.0.0"
 gem "nokogiri", "~> 1.10"
 gem "pry"
 gem "rspec", "~> 3.9"
 gem "rubocop", "~> 1.20"
 gem "rubocop-rspec", "~> 2.4"
+gem "mongoid", "~> 8.0.0"
 
 gemspec path: "../"

gemfiles/rails_6.1.gemfile

@@ -2,16 +2,16 @@
 
 source "https://rubygems.org"
 
-gem "activerecord-jdbcsqlite3-adapter", "~> 61.0", platform: :jruby
 gem "appraisal", git: "https://github.com/thoughtbot/appraisal.git", branch: :main
 gem "bigdecimal"
 gem "fakefs", "~> 1.2"
 gem "nokogiri", "~> 1.10"
 gem "pry"
-gem "rails", "~> 6.1.0"
 gem "rspec", "~> 3.9"
 gem "rubocop", "~> 1.20"
 gem "rubocop-rspec", "~> 2.4"
+gem "activerecord-jdbcsqlite3-adapter", "~> 61.0", platform: :jruby
+gem "rails", "~> 6.1.0"
 gem "sqlite3", "~> 1.4", platform: :mri
 
 gemspec path: "../"

gemfiles/rails_7.0.gemfile

@@ -2,16 +2,16 @@
 
 source "https://rubygems.org"
 
-gem "activerecord-jdbcsqlite3-adapter", "~> 70.0", platform: :jruby
 gem "appraisal", git: "https://github.com/thoughtbot/appraisal.git", branch: :main
 gem "bigdecimal"
 gem "fakefs", "~> 1.2"
 gem "nokogiri", "~> 1.10"
 gem "pry"
-gem "rails", "~> 7.0.0"
 gem "rspec", "~> 3.9"
 gem "rubocop", "~> 1.20"
 gem "rubocop-rspec", "~> 2.4"
+gem "activerecord-jdbcsqlite3-adapter", "~> 70.0", platform: :jruby
+gem "rails", "~> 7.0.0"
 gem "sqlite3", "~> 1.4", platform: :mri
 
 gemspec path: "../"

gemfiles/sequel_5.0.gemfile

@@ -5,12 +5,12 @@ source "https://rubygems.org"
 gem "appraisal", git: "https://github.com/thoughtbot/appraisal.git", branch: :main
 gem "bigdecimal"
 gem "fakefs", "~> 1.2"
-gem "jdbc-sqlite3", platform: :jruby
 gem "nokogiri", "~> 1.10"
 gem "pry"
 gem "rspec", "~> 3.9"
 gem "rubocop", "~> 1.20"
 gem "rubocop-rspec", "~> 2.4"
+gem "jdbc-sqlite3", platform: :jruby
 gem "sequel", "~> 5.0"
 gem "sqlite3", "~> 1.4", platform: :mri
 

lib/amazing_print/ext/active_record.rb

@@ -20,6 +20,10 @@ def cast_with_active_record(object, type)
 
       if object.is_a?(::ActiveRecord::Base)
         cast = :active_record_instance
+      elsif object.is_a?(Class) && object.include?(::ActiveModel::Attributes)
+        cast = :active_model_class
+      elsif object.is_a?(::ActiveModel::Attributes)
+        cast = :active_model_instance
       elsif object.is_a?(::ActiveModel::Errors)
         cast = :active_model_error
       elsif object.is_a?(Class) && object.ancestors.include?(::ActiveRecord::Base)
@@ -71,6 +75,32 @@ def awesome_active_record_class(object)
       [awesome_simple("class #{object} < #{object.superclass}", :class), awesome_hash(data)].join(' ')
     end
 
+    # Format ActiveModel instance object.
+    #------------------------------------------------------------------------------
+    def awesome_active_model_instance(object)
+      return object.inspect unless defined?(::ActiveSupport::OrderedHash)
+      return awesome_object(object) if @options[:raw]
+
+      data = object.attributes.each_with_object(::ActiveSupport::OrderedHash.new) do |c, hash|
+        hash[c.first.to_sym] = c.last
+      end
+
+      [awesome_simple(object.to_s, :active_model_instance), awesome_hash(data)].join(' ')
+    end
+
+    # Format ActiveModel class object.
+    #------------------------------------------------------------------------------
+    def awesome_active_model_class(object)
+      return object.inspect unless defined?(::ActiveSupport::OrderedHash)
+      return awesome_class(object) if @options[:raw]
+
+      data = object.attribute_types.each_with_object(::ActiveSupport::OrderedHash.new) do |c, hash|
+        hash[c.first.to_sym] = c.last.type
+      end
+
+      [awesome_simple("class #{object} < #{object.superclass}", :class), awesome_hash(data)].join(' ')
+    end
+
     # Format ActiveModel error object.
     #------------------------------------------------------------------------------
     def awesome_active_model_error(object)

spec/active_record_helper.rb

@@ -40,4 +40,11 @@ def attributes
       { 'name' => name }
     end
   end
+
+  class ActiveModelModel
+    include ::ActiveModel::Model
+    include ::ActiveModel::Attributes
+    attribute :name, :string
+    attribute :rank, :integer, default: 0
+  end
 end

spec/ext/active_model_spec.rb

@@ -3,11 +3,34 @@
 require 'spec_helper'
 require 'active_record_helper'
 
-RSpec.describe 'ActiveModel::Errors formatting', skip: -> { !ExtVerifier.has_rails? }.call do
+RSpec.describe 'ActiveModel formatting', skip: -> { !ExtVerifier.has_rails? }.call do
   before do
     @ap = AmazingPrint::Inspector.new(plain: true)
   end
 
+  describe 'ActiveModel class' do
+    it 'prints the class' do
+      expect(@ap.awesome(ActiveModelModel)).to eq <<~PRINT.strip
+        class ActiveModelModel < Object {
+            :name => :string,
+            :rank => :integer
+        }
+      PRINT
+    end
+  end
+
+  describe 'ActiveModel instance' do
+    it 'prints the instance' do
+      model = ActiveModelModel.new(name: 'John', rank: 1)
+      expect(@ap.awesome(model)).to be_similar_to <<~PRINT.strip
+        #<ActiveModelModel:placeholder_id> {
+            :name => "John",
+            :rank => 1
+        }
+      PRINT
+    end
+  end
+
   it 'formats active_model_errors properly' do
     model = TableFreeModel.new
     model.errors.add(:name, "can't be blank")