Add mapPatch

src/DiffSummary.hs

@@ -44,12 +44,8 @@ diffSummaries sources = para $ \diff ->
       annotateWithCategory children = maybeToList (prependSummary (Both.snd sources) <$> (afterTerm diff')) <*> (children >>= snd) in
   case diff of
     -- Skip comments and leaves since they don't have any changes
-    Free (_ :< Leaf _) -> []
-    Free (_ :< (S.Comment _)) -> []
     (Free (_ :< syntax)) -> annotateWithCategory (toList syntax)
-    (Pure (Insert term)) -> [ DiffSummary (Insert $ termToDiffInfo afterSource term) [] ]
-    (Pure (Delete term)) -> [ DiffSummary (Delete $ termToDiffInfo beforeSource term) [] ]
-    (Pure (Replace t1 t2)) -> [ DiffSummary (Replace (termToDiffInfo beforeSource t1) (termToDiffInfo afterSource t2)) [] ]
+    (Pure patch) -> [ DiffSummary (mapPatch (termToDiffInfo beforeSource) (termToDiffInfo afterSource) patch) [] ]
   where
     (beforeSource, afterSource) = runJoin sources
 
@@ -122,7 +118,7 @@ toTermName source term = case unwrap term of
 maybeParentContext :: [(Category, Text)] -> Doc
 maybeParentContext annotations = case annotations of
   [] -> ""
-  (annotation:xs) -> space <> "in the" <+> (toDoc $ snd annotation) <+> toDoc (toCategoryName $ fst annotation)
+  (annotation:_) -> space <> "in the" <+> (toDoc $ snd annotation) <+> toDoc (toCategoryName $ fst annotation)
 toDoc :: Text -> Doc
 toDoc = string . toS
 

src/Patch.hs

@@ -9,6 +9,7 @@ module Patch
 , patchSum
 , maybeFst
 , maybeSnd
+, mapPatch
 ) where
 
 import Data.These
@@ -51,6 +52,11 @@ unPatch (Replace a b) = These a b
 unPatch (Insert b) = That b
 unPatch (Delete a) = This a
 
+mapPatch :: (a -> b) -> (a -> b) -> Patch a -> Patch b
+mapPatch f _ (Delete  a  ) = Delete  (f a)
+mapPatch _ g (Insert    b) = Insert  (g b)
+mapPatch f g (Replace a b) = Replace (f a) (g b)
+
 -- | Calculate the cost of the patch given a function to compute the cost of a item.
 patchSum :: (a -> Integer) -> Patch a -> Integer
 patchSum termCost patch = maybe 0 termCost (before patch) + maybe 0 termCost (after patch)