Fix pretty printing of logging output

Language/Haskell/GhcMod/HomeModuleGraph.hs

@@ -222,7 +222,7 @@ updateHomeModuleGraph' env smp0 = do
           Left errs -> do
             -- TODO: Remember these and present them as proper errors if this is
             -- the file the user is looking at.
-            gmLog GmWarning ("preprocess' " ++ show fn) $ vcat $ map strDoc errs
+            gmLog GmWarning ("preprocess " ++ show fn) $ empty $+$ (vcat $ map text errs)
             return Nothing
 
    imports :: ModulePath -> String -> DynFlags -> MaybeT m (Set ModulePath)

Language/Haskell/GhcMod/Logging.hs

@@ -60,8 +60,8 @@ gmLog level loc' doc = do
   GhcModLog { gmLogLevel = level' } <- gmlHistory
 
   let loc | loc' == "" = empty
-          | otherwise = empty <+>: text loc'
-      msg = gmRenderDoc $ (gmLogLevelDoc level <> loc) <+>: doc
+          | otherwise = text loc' <+>: empty
+      msg = gmRenderDoc $ gmLogLevelDoc level <+>: sep [loc, doc]
       msg' = dropWhileEnd isSpace msg
 
   when (Just level <= level') $