Rspec Integration Test with Grape and Rails 4.2.x

Issue:
Your using grape, rails 4.2.x and rspec and you get an error about Array not responding to url_helpers

Fix:

    if Rails.version >= '4.2' && Rails.version < '5'
      #see actionpack/lib/action_dispatch/testing/integration.rb:184 rails 4.2.6
      #expects a rails app if resposnds to routes but we've got a grape app that responds to routes
      module ActionDispatch
        module Integration
          class Session
            def initialize(app)
              super()
              @app = app
              if app.respond_to?(:routes) && app.routes.respond_to?(:url_helpers)
                singleton_class.class_eval do
                  include app.routes.url_helpers
                  include app.routes.mounted_helpers
                end
              end
              reset!
            end
          end
        end
      end
    end

Reproduce the integration-test failure with Grape, Rails 4.2.x, and RSpec, then inspect actionpack/lib/action_dispatch/testing/integration.rb around line 184 as identified in the issue. Compare the behavior for a Grape app and a Rails app, and verify that the integration test runs without the Array/url_helpers error across the stated Rails versions.