Module: ActiveSupport::DescendantsTracker

Relationships & Source Files
Extension / Inclusion / Inheritance Descendants
Extended In: `::AbstractController::Base`, ActionCable::Engine, `::ActionController::API`, `::ActionController::Base`, `::ActionController::Metal`, ActionController::Railtie, ActionDispatch::Railtie, `::ActionMailbox::Engine`, `::ActionMailer::Base`, `::ActionMailer::Preview`, ActionMailer::Railtie, `::ActionText::Engine`, ActionView::Railtie, `::ActionView::TestCase::TestController`, ActiveJob::Railtie, ActiveModel::Railtie, `::ActiveRecord::Base`, ActiveRecord::Railtie, ActiveStorage::Engine, ActiveSupport::Railtie, I18n::Railtie, `::Rails::Application`, Rails::ApplicationController, `::Rails::Engine`, `::Rails::HealthController`, Rails::InfoController, Rails::MailersController, Rails::PwaController, `::Rails::Railtie`, `::Rails::TestUnitRailtie`, Rails::WelcomeController
Defined in:	activesupport/lib/active_support/descendants_tracker.rb

Overview

This module provides an internal implementation to track descendants which is faster than iterating through ObjectSpace.

However Ruby 3.1 provide a fast native Class#subclasses method, so if you know your code won’t be executed on older rubies, including DescendantsTracker does not provide any benefit.

Instance Method Summary

#descendants

Class Method Details

.descendants(klass)

[ GitHub ]

# File 'activesupport/lib/active_support/descendants_tracker.rb', line 102


def descendants(klass)
  klass.descendants
end

.subclasses(klass)

[ GitHub ]

# File 'activesupport/lib/active_support/descendants_tracker.rb', line 98


def subclasses(klass)
  klass.subclasses
end

Instance Method Details

#descendants

[ GitHub ]

# File 'activesupport/lib/active_support/descendants_tracker.rb', line 107


def descendants
  subclasses = DescendantsTracker.reject!(self.subclasses)
  subclasses.concat(subclasses.flat_map(&:descendants))
end