Don't choke when controller is not present in the request

Co-authored-by: Bijan Rahnema <bijan@screenisland.com>

Author: jorgemanrubia

lib/hotwire/spark/middleware.rb

@@ -6,7 +6,7 @@ def initialize(app)
   def call(env)
     status, headers, response = @app.call(env)
 
-    if html_response?(headers)
+    if interceptable_request?(headers) && html_response?(headers)
       @request = ActionDispatch::Request.new(env)
       html = html_from(response)
       html = inject_javascript(html)
@@ -19,6 +19,10 @@ def call(env)
   end
 
   private
+    def interceptable_request?(headers)
+      headers["action_controller.instance"]
+    end
+
     def html_response?(headers)
       headers["Content-Type"]&.include?("text/html")
     end

test/middleware_test.rb

@@ -0,0 +1,7 @@
+require "application_system_test_case"
+
+class MiddlewareTest < ActionDispatch::IntegrationTest
+  test "error" do
+    get "/redirected"
+  end
+end