fix(corrections-grade-r): add get following post

Fixes #532

src/Handler/Corrections.hs

@@ -1132,26 +1132,24 @@ postCorrectionsGradeR = do
     { dbParamsFormAction = Just $ SomeRoute CorrectionsGradeR
     }
 
-  case tableRes of
-    FormMissing -> return ()
-    FormFailure errs -> forM_ errs $ addMessage Error . toHtml
-    FormSuccess resMap -> do
-      now <- liftIO getCurrentTime
-      subs <- fmap catMaybes . runDB . forM (Map.toList resMap) $ \(subId, (rated, mPoints, mComment)) -> do
-        s@Submission{..} <- get404 subId
-        if
-          | submissionRatingPoints /= mPoints || submissionRatingComment /= mComment || rated /= submissionRatingDone s
-            -> do audit $ TransactionSubmissionEdit subId $ s ^. _submissionSheet
-                  Just subId <$ update subId [ SubmissionRatingPoints =. mPoints
-                                             , SubmissionRatingComment =. mComment
-                                             , SubmissionRatingBy =. Just uid
-                                             , SubmissionRatingTime =. now <$ guard rated
-                                             ]
-          | otherwise -> return Nothing
-      subs' <- traverse (\x -> (,) <$> encrypt x <*> encrypt x) subs :: Handler [(CryptoFileNameSubmission, CryptoUUIDSubmission)]
-      let trigger = [whamlet|_{MsgCorrectionsUploaded (genericLength subs')}|]
-          content = Right $(widgetFile "messages/correctionsUploaded")
-      unless (null subs') $ addMessageModal Success trigger content
+  formResult tableRes $ \resMap -> do
+    now <- liftIO getCurrentTime
+    subs <- fmap catMaybes . runDB . forM (Map.toList resMap) $ \(subId, (rated, mPoints, mComment)) -> do
+      s@Submission{..} <- get404 subId
+      if
+        | submissionRatingPoints /= mPoints || submissionRatingComment /= mComment || rated /= submissionRatingDone s
+          -> do audit $ TransactionSubmissionEdit subId $ s ^. _submissionSheet
+                Just subId <$ update subId [ SubmissionRatingPoints =. mPoints
+                                           , SubmissionRatingComment =. mComment
+                                           , SubmissionRatingBy =. Just uid
+                                           , SubmissionRatingTime =. now <$ guard rated
+                                           ]
+        | otherwise -> return Nothing
+    subs' <- traverse (\x -> (,) <$> encrypt x <*> encrypt x) subs :: Handler [(CryptoFileNameSubmission, CryptoUUIDSubmission)]
+    let trigger = [whamlet|_{MsgCorrectionsUploaded (genericLength subs')}|]
+        content = Right $(widgetFile "messages/correctionsUploaded")
+    unless (null subs') $ addMessageModal Success trigger content
+    redirect CorrectionsGradeR
 
   siteLayoutMsg MsgCorrectionsGrade $ do
     setTitleI MsgCorrectionsGrade