1 files changed, 28 insertions, 16 deletions
diff --git a/app/TreeGrepper/Comment.hs b/app/TreeGrepper/Comment.hs
index 0ca9543..7c2ca90 100644
--- a/app/TreeGrepper/Comment.hs
+++ b/app/TreeGrepper/Comment.hs
@@ -7,7 +7,7 @@ module TreeGrepper.Comment
   )
 where
 
-import Control.Exception (throw)
+import Control.Exception (catch, throw)
 import Data.Aeson qualified as A
 import Data.Binary (Binary)
 import Data.ByteString.Lazy.Char8 qualified as B
@@ -15,11 +15,15 @@ import Data.Function ((&))
 import Data.List (find)
 import Data.Maybe (fromMaybe)
 import Data.Text qualified as T
+import Data.Text.Lazy.IO qualified as LT
 import Exception qualified as E
 import GHC.Generics (Generic)
+import Git qualified
 import Process (proc, sh)
-import System.FilePath (takeExtension)
-import System.Process.Typed (setWorkingDir)
+import System.Directory (createDirectoryIfMissing)
+import System.FilePath (takeDirectory, takeExtension, takeFileName, (</>))
+import System.IO.Temp (withSystemTempDirectory)
+import System.Process.Typed qualified as P
 import TreeGrepper.FileType (FileType (..))
 import TreeGrepper.FileType qualified as G
 import TreeGrepper.Match (Match (..), Position (..))
@@ -90,20 +94,28 @@ stripBlockComment blockStart blockEnd text =
 fromMatch :: Result -> Match -> Comment
 fromMatch Result {..} Match {..} = Comment {..}
 
-getComments :: FilePath -> FilePath -> IO [Comment]
-getComments cwd fn = do
+getComments :: Git.CommitHash -> FilePath -> IO [Comment]
+getComments commitHash fn = do
   let ext = takeExtension fn
-  concatMap (\result -> map (fromMatch result) result.matches)
-    . map fixTreeGrepper
-    . decode
-    <$> sh
-      ( proc
-          "tree-grepper --query % % --format json %"
-          (treeGrepperLanguage ext)
-          (treeGrepperQuery ext)
-          fn
-          & setWorkingDir cwd
-      )
+  s <-
+    catch
+      (Git.readTextFileOf commitHash fn)
+      (\(_ :: E.ProcessException) -> pure "")
+  withSystemTempDirectory (takeFileName fn) $ \cwd -> do
+    createDirectoryIfMissing True (cwd </> takeDirectory fn)
+    LT.writeFile (cwd </> fn) s
+    concatMap (\result -> map (fromMatch result) result.matches)
+      . map fixTreeGrepper
+      . decode
+      <$> sh
+        ( ( proc
+              "tree-grepper % --query % % --format json"
+              fn
+              (treeGrepperLanguage ext)
+              (treeGrepperQuery ext)
+          )
+            & P.setWorkingDir cwd
+        )
 
 decode :: B.ByteString -> [Result]
 decode = either (throw . E.InvalidTreeGrepperResult) id . A.eitherDecode