instance method qualified_const_defined?

# File activesupport/lib/active_support/core_ext/module/qualified_const.rb, line 29
  def qualified_const_defined?(path, search_parents=true)
    ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
      Module#qualified_const_defined? is deprecated in favour of the builtin
      Module#const_defined? and will be removed in Rails 5.1.
    MESSAGE

    ActiveSupport::QualifiedConstUtils.raise_if_absolute(path)

    ActiveSupport::QualifiedConstUtils.names(path).inject(self) do |mod, name|
      return unless mod.const_defined?(name, search_parents)
      mod.const_get(name)
    end
    return true
  end