2 files changed, 23 insertions, 5 deletions
diff --git a/actionpack/lib/action_controller/metal/live.rb b/actionpack/lib/action_controller/metal/live.rb
index d60f1b0d44..43cf9b9723 100644
--- a/actionpack/lib/action_controller/metal/live.rb
+++ b/actionpack/lib/action_controller/metal/live.rb
@@ -177,13 +177,17 @@ module ActionController
         end
       end
 
-      def commit!
-        headers.freeze
+      private
+
+      def finalize_response
         super
+        jar = request.cookie_jar
+        # The response can be committed multiple times
+        jar.write self unless jar.committed?
+        jar.commit!
+        headers.freeze
       end
 
-      private
-
       def build_buffer(response, body)
         buf = Live::Buffer.new response
         body.each { |part| buf.write part }
diff --git a/actionpack/lib/action_controller/test_case.rb b/actionpack/lib/action_controller/test_case.rb
index 33a5858766..009f83861d 100644
--- a/actionpack/lib/action_controller/test_case.rb
+++ b/actionpack/lib/action_controller/test_case.rb
@@ -267,6 +267,18 @@ module ActionController
     def body
       @body ||= super
     end
+
+    # Was the response successful?
+    alias_method :success?, :successful?
+
+    # Was the URL not found?
+    alias_method :missing?, :not_found?
+
+    # Were we redirected?
+    alias_method :redirect?, :redirection?
+
+    # Was there a server-side error?
+    alias_method :error?, :server_error?
   end
 
   # Methods #destroy and #load! are overridden to avoid calling methods on the
@@ -583,7 +595,9 @@ module ActionController
         @controller.process(name)
 
         if cookies = @request.env['action_dispatch.cookies']
-          cookies.write(@response)
+          unless cookies.committed?
+            cookies.write(@response)
+          end
         end
         @response.prepare!