Process violations in order

Since we now collect all violations before changing the original contents, we
can process the violations in order instead of from last to first (otherwise
locations within the file would change).

src/Annotator.hs

@@ -16,7 +16,7 @@ import Control.Monad.IO.Class
 import Control.Monad.Trans.Reader
 import Control.Exception (evaluate)
 import Data.Function (on)
-import Data.List (delete, intercalate, foldl')
+import Data.List (delete, intercalate, foldl', sortBy)
 import Data.Char (isSpace)
 import Data.Ord
 import Data.Monoid
@@ -29,7 +29,7 @@ import Annotator.Rule
 import Annotator.Annotation
 
 version :: Vsn.Version
-version = Vsn.makeVersion [0,0,2,0]
+version = Vsn.makeVersion [0,0,2,1]
 
 type App a = ReaderT Options IO a
 
@@ -200,7 +200,7 @@ genericMain file = do
 
   case mviolations of
     Just violations -> do
-      let sortedViolations = NE.sortBy reverseOccurrences violations
+      let sortedViolations = NE.sortBy compareLocation violations
           groupedViolations = NE.groupBy ((==) `on` filename) sortedViolations
       verbose Chatty $ "all violations: " <> show sortedViolations
       forM_ groupedViolations handleViolations
@@ -209,8 +209,8 @@ genericMain file = do
       liftIO $ hPutStrLn stderr "Defects file is empty"
 
   where
-    reverseOccurrences :: Violation -> Violation -> Ordering
-    reverseOccurrences = comparing filename <> flip (comparing line)
+    compareLocation :: Violation -> Violation -> Ordering
+    compareLocation = comparing filename <> comparing line
 
     isRelevant :: Bool -> Violation -> Bool
     isRelevant newestOnly v
@@ -235,14 +235,17 @@ handleViolations violations = do
   if fileExists
     then do
       liftIO $ hPutStrLn stderr header
-      contents <- liftIO $ readFile fname
-      _ <- liftIO $ evaluate (length contents) -- ensure file is completely read
 
-      let numberedContent = zip [1..] . lines $ contents
+      verbose Chatty $ show violations
 
-      annotations <- (catMaybes . NE.toList) <$> mapM (handleViolation contents) violations
+      content <- liftIO $ readFile fname
+      _ <- liftIO $ evaluate (length content) -- ensure file is completely read
 
-      let annotatedLines = fmap annotationToLine annotations
+      let numberedContent = zip [1..] . lines $ content
+
+      annotations <- (catMaybes . NE.toList) <$> mapM (handleViolation content) violations
+
+      let annotatedLines = sortBy (comparing fst) $ fmap annotationToLine annotations
           newContent = unlines . map snd $ mergeLines annotatedLines numberedContent
 
       liftIO $ writeFile fname' newContent
@@ -337,6 +340,8 @@ handleViolation content v@Violation{..} = do
       context = getContext (contextLines opts) before after
       indent = takeWhile isSpace (snd . head $ after)
 
+  verbose Chatty $ "indentation: " <> show indent
+
   -- print some context
   liftIO $ forM_ context (\(n, code) -> do
                     let marker = ">>>>"