TOSQUASH annoying GHC version fixup

Author: nfrisby

ouroboros-consensus/ouroboros-consensus.cabal

@@ -379,6 +379,7 @@ library unstable-consensus-testlib
     Test.CsjModel.NonEmptySeq
     Test.CsjModel.Perm
     Test.CsjModel.StateTypes
+    Test.CsjModel.UglyStylishHaskellCppWorkaround
     Test.LedgerTables
     Test.Ouroboros.Consensus.ChainGenerator.Adversarial
     Test.Ouroboros.Consensus.ChainGenerator.BitVector

ouroboros-consensus/src/ouroboros-consensus/Ouroboros/Consensus/MiniProtocol/ChainSync/Client/Jumping.hs

@@ -4,6 +4,7 @@
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE StandaloneDeriving #-}
@@ -303,7 +304,11 @@ mkJumping peerContext = Jumping
         atomically (nextInstruction (pure ()) peerContext) >>= \case
             Strict.Right instr -> pure instr
             Strict.Left () -> do
-                traceWith (tracer peerContext) BlockedOnJump
+                -- Need to use NamedFieldPuns somewhere in this module,
+                -- otherwise stylish-haskell complains. But if I remove the
+                -- LANGUAGE pragma, then there's a lot of name-shadowing
+                -- warnings.
+                traceWith (let Context{tracer} = peerContext in tracer) BlockedOnJump
                 id
                   $ fmap (Strict.either absurd id)
                   $ atomically

ouroboros-consensus/src/unstable-consensus-testlib/Test/CsjModel.hs

@@ -30,7 +30,6 @@ import           Control.Applicative ((<|>))
 import           Control.Arrow (first)
 import           Control.Monad (guard)
 import qualified Control.Monad.State.Strict as State
-import           Data.Foldable (foldl')
 import qualified Data.Map.Strict as Map
 import qualified Data.Maybe as L (Maybe (Just, Nothing), isJust, maybe)
 import           Data.Sequence (Seq)
@@ -48,6 +47,7 @@ import           Prelude hiding (Either (Left, Right), Maybe (Just, Nothing),
 import           Test.CsjModel.NonEmptySeq
 import           Test.CsjModel.Perm
 import           Test.CsjModel.StateTypes
+import           Test.CsjModel.UglyStylishHaskellCppWorkaround (foldl')
 
 {-------------------------------------------------------------------------------
   Stimuli to and reactions of the CSJ governor

ouroboros-consensus/src/unstable-consensus-testlib/Test/CsjModel/UglyStylishHaskellCppWorkaround.hs

@@ -0,0 +1,12 @@
+{-# LANGUAGE CPP #-}
+
+-- | This module exists because:
+--
+-- - @foldl'@ was added as an export of 'Prelude' starting with GHC 9.10.1
+--
+-- - @stylish-haskell@ mangles import lists that involve CPP
+module Test.CsjModel.UglyStylishHaskellCppWorkaround (foldl') where
+
+#if __GLASGOW_HASKELL__ < 9101
+import           Data.Foldable (foldl')
+#endif