Make hpack default to only outputting warnings #2011

src/Stack/Package.hs

@@ -42,7 +42,7 @@ import Prelude.Compat
 
 import           Control.Arrow ((&&&))
 import           Control.Exception hiding (try,catch)
-import           Control.Monad (liftM, liftM2, (<=<), when, forM)
+import           Control.Monad (liftM, liftM2, (<=<), when, forM, forM_)
 import           Control.Monad.Catch
 import           Control.Monad.IO.Class
 import           Control.Monad.Logger
@@ -1125,8 +1125,18 @@ hpack pkgDir = do
     when exists $ do
         let fpt = T.pack (toFilePath hpackFile)
         $logDebug $ "Running hpack on " <> fpt
-        liftIO $ Hpack.hpack (toFilePath pkgDir) True
-        $logDebug  $ "Done running hpack on " <> fpt
+        r <- liftIO $ Hpack.hpackResult (toFilePath pkgDir)
+        forM_ (Hpack.resultWarnings r) $ \w -> $logWarn ("WARNING: " <> T.pack w)
+        let cabalFile = T.pack (Hpack.resultCabalFile r)
+        case Hpack.resultStatus r of
+            Hpack.Generated -> $logDebug $
+                "hpack generated a modified version of " <> cabalFile
+            Hpack.OutputUnchanged -> $logDebug $
+                "hpack output unchanged in " <> cabalFile
+            -- NOTE: this is 'logInfo' so it will be outputted to the
+            -- user by default.
+            Hpack.AlreadyGeneratedByNewerHpack -> $logWarn $
+                "WARNING: " <> cabalFile <> " was generated with a newer version of hpack, please upgrade and try again."
 
 -- | Path for the package's build log.
 buildLogPath :: (MonadReader env m, HasBuildConfig env, MonadThrow m)

stack-7.8.yaml

@@ -31,7 +31,7 @@ extra-deps:
 - process-1.2.1.0
 - time-1.5.0.1
 - base-compat-0.9.0
-- hpack-0.10.0
+- hpack-0.14.0
 - microlens-0.4.1.0
 - open-browser-0.2.1.0
 - tls-1.3.5

stack-8.0.yaml

@@ -19,7 +19,7 @@ nix:
   packages:
     - zlib
 extra-deps:
-- hpack-0.12.0
+- hpack-0.14.0
 - path-0.5.7
 - path-io-1.1.0
 - transformers-0.5.2.0

stack.cabal

@@ -218,7 +218,7 @@ library
                    , hastache
                    , project-template >= 0.2
                    , zip-archive
-                   , hpack >= 0.10.0 && < 0.15
+                   , hpack >= 0.14.0 && < 0.15
   if os(windows)
     cpp-options:     -DWINDOWS
     build-depends:   Win32