module ActiveSupport::Autoload

def self.extended(base) # :nodoc:
  if RUBY_VERSION < "3"
    base.class_eval do
      @_autoloads = nil
      @_under_path = nil
      @_at_path = nil
      @_eager_autoload = false
      @_eagerloaded_constants = nil
    end
  end
end

def autoload(const_name, path = @_at_path)
  unless path
    full = [name, @_under_path, const_name.to_s].compact.join("::")
    path = Inflector.underscore(full)
  end
  if @_eager_autoload
    @_eagerloaded_constants ||= []
    @_eagerloaded_constants << const_name
  end
  super const_name, path
end

def autoload_at(path)
  @_at_path, old_path = path, @_at_path
  yield
ensure
  @_at_path = old_path
end

def autoload_under(path)
  @_under_path, old_path = path, @_under_path
  yield
ensure
  @_under_path = old_path
end

def eager_autoload
  old_eager, @_eager_autoload = @_eager_autoload, true
  yield
ensure
  @_eager_autoload = old_eager
end

def eager_load!
  if @_eagerloaded_constants
    @_eagerloaded_constants.each { |const_name| const_get(const_name) }
    @_eagerloaded_constants = nil
  end
end