[Feature request] Allow html to be saved on failiure for rspecs ran with rack_test driver

rubyonrails-core
1

My goal is to have an rspec system spec run with rack_test and to save the html on failure to be able to investigate.

This is possible for selenium driver, but I can’t find a way to make it work for rack_test and I feel like I am missing something so I am suggesting this new feature.

I would imagine that it should be possible to go to spec/rails_helper.rb and define

RSpec.configure do |config|
  config.after(:each) do 
     save_html? # this does not work
  end
end

In this way we can save the html of the page. The problem is the page.body at this stage is “”, because the method Capybara.reset_session! was called. And it is called here:

# frozen_string_literal: true

module ActionDispatch
  module SystemTesting
    module TestHelpers
      module SetupAndTeardown # :nodoc:
        def host!(host)
          ActiveSupport::Deprecation.warn \
            "ActionDispatch::SystemTestCase#host! is deprecated with no replacement. " \
            "Set Capybara.app_host directly or rely on Capybara's default host."

          Capybara.app_host = host
        end

        def before_teardown
          take_failed_screenshot
        ensure
          super
        end

        def after_teardown
          Capybara.reset_sessions!
        ensure
          super
        end
      end
    end
  end
end

This means that the session is reset and only then the config(:after) in the spec/rails_helper is executed.

The call to take_failed_screenshot is

   44:         def take_failed_screenshot 
   45:           take_screenshot if failed? && supports_screenshot?
   46:         end

which checks if screenshot is supported

[128, 137] in /home/kireto/.rvm/gems/ruby-2.7.4/gems/actionpack-6.1.5/lib/action_dispatch/system_testing/test_helpers/screenshot_helper.rb
   128:           def failed?
   129:             !passed? && !skipped?
   130:           end
   131: 
   132:           def supports_screenshot?
=> 133:             Capybara.current_driver != :rack_test
   134:           end
   135:       end
   136:     end
   137:   end

Because the driver is rack_test we naturally skip the rest. And after that the session is reset with Capybara.reset_session! and after that our config.after(:each) block is called and there is no longer a session and a page and the html can not be saved.

I understand that a screenshot can not be taken with the rack_test. That’s find. But the html can be saved?

What do you think about introducing a feature where at least the HTML of the page could be saved for an rspec ran with rack_test?