module RSpec::Rails::HelperExampleGroup

def _controller_path(example)
  example.example_group.described_class.to_s.sub(/Helper/, '').underscore
end

mixed in, along with any of the built-in rails helpers.
Returns an instance of ActionView::Base with the helper being specified

def helper
  _view.tap do |v|
    v.extend(ApplicationHelper) if defined?(ApplicationHelper)
    v.assign(view_assigns)
  end
end