module ActionDispatch::TestHelpers::PageDumpHelper

def save_and_open_page(path = html_dump_default_path)

Launchy must be present in your Gemfile for the page to open automatically.
Saves the content of response body to a file and tries to open it in your browser.
def save_and_open_page(path = html_dump_default_path)
  save_page(path).tap { |s_path| open_file(s_path) }
end