Merge pull request haskell#9330 from ulysses4ever/ci-ghc-9.8

GHC 9.8 compat and CI

.github/workflows/validate.yml

@@ -49,7 +49,7 @@ jobs:
     strategy:
       matrix:
         os: ["ubuntu-latest", "macos-latest", "windows-latest"]
-        ghc: ["9.6.3", "9.4.7", "9.2.8", "9.0.2", "8.10.7", "8.8.4", "8.6.5", "8.4.4"]
+        ghc: ["9.8.1", "9.6.3", "9.4.8", "9.2.8", "9.0.2", "8.10.7", "8.8.4", "8.6.5", "8.4.4"]
         exclude:
           # corrupts GHA cache or the fabric of reality itself, see https://github.com/haskell/cabal/issues/8356
           - os: "windows-latest"
@@ -83,7 +83,7 @@ jobs:
         id: setup-haskell
         with:
           ghc-version: ${{ matrix.ghc }}
-          cabal-version: '3.10.1.0'
+          cabal-version: latest # latest is mandatory for cabal-testsuite, see https://github.com/haskell/cabal/issues/8133
 
       - name: Work around git problem https://bugs.launchpad.net/ubuntu/+source/git/+bug/1993586 (cabal PR #8546)
         run: |
@@ -117,11 +117,6 @@ jobs:
           fi
           echo "FLAGS=$FLAGS" >> $GITHUB_ENV
 
-      - name: Allow newer dependencies when built with latest GHC
-        if: ${{ matrix.ghc }} == '9.6.3'
-        run: |
-          echo "allow-newer: rere:base, rere:transformers" >> cabal.project.validate
-
       - name: Validate print-config
         run: sh validate.sh $FLAGS -s print-config
 

Cabal-tests/tests/UnitTests/Distribution/Utils/Structured.hs

@@ -25,7 +25,12 @@ tests = testGroup "Distribution.Utils.Structured"
     , testCase "SPDX.License" $
       md5Check (Proxy :: Proxy License) 0xd3d4a09f517f9f75bc3d16370d5a853a
     -- The difference is in encoding of newtypes
-#if MIN_VERSION_base(4,7,0)
+#if MIN_VERSION_base(4,19,0)
+    , testCase "GenericPackageDescription" $
+      md5Check (Proxy :: Proxy GenericPackageDescription) 0xf5fdb32b43aca790192f44d9ecaa9689
+    , testCase "LocalBuildInfo" $
+      md5Check (Proxy :: Proxy LocalBuildInfo) 0x205fbe2649bc5e488bce50c07a71cadb
+#elif MIN_VERSION_base(4,7,0)
     , testCase "GenericPackageDescription" $
       md5Check (Proxy :: Proxy GenericPackageDescription) 0xb287a6f04e34ef990cdd15bc6cb01c76
     , testCase "LocalBuildInfo" $

Cabal/src/Distribution/Simple/GHC.hs

@@ -161,14 +161,14 @@ configure verbosity hcPath hcPkgPath conf0 = do
       (userMaybeSpecifyPath "ghc" hcPath conf0)
   let implInfo = ghcVersionImplInfo ghcVersion
 
-  -- Cabal currently supports ghc >= 7.0.1 && < 9.8
+  -- Cabal currently supports ghc >= 7.0.1 && < 9.10
   -- ... and the following odd development version
-  unless (ghcVersion < mkVersion [9, 8]) $
+  unless (ghcVersion < mkVersion [9, 10]) $
     warn verbosity $
       "Unknown/unsupported 'ghc' version detected "
         ++ "(Cabal "
         ++ prettyShow cabalVersion
-        ++ " supports 'ghc' version < 9.8): "
+        ++ " supports 'ghc' version < 9.10): "
         ++ programPath ghcProg
         ++ " is version "
         ++ prettyShow ghcVersion

cabal-dev-scripts/cabal-dev-scripts.cabal

@@ -18,7 +18,7 @@ executable gen-spdx
   ghc-options:      -Wall
   build-depends:
     , aeson                 ^>=1.4.1.0 || ^>=1.5.2.0 || ^>=2.1.1.0
-    , base                  >=4.10     && <4.19
+    , base                  >=4.10     && <4.20
     , bytestring
     , containers
     , Diff                  ^>=0.4
@@ -35,7 +35,7 @@ executable gen-spdx-exc
   ghc-options:      -Wall
   build-depends:
     , aeson                 ^>=1.4.1.0 || ^>=1.5.2.0 || ^>=2.1.1.0
-    , base                  >=4.10     && <4.19
+    , base                  >=4.10     && <4.20
     , bytestring
     , containers
     , Diff                  ^>=0.4

cabal-install/src/Distribution/Client/Dependency.hs

@@ -67,7 +67,6 @@ module Distribution.Client.Dependency
   ) where
 
 import Distribution.Client.Compat.Prelude
-import qualified Prelude as Unsafe (head)
 
 import Distribution.Client.Dependency.Types
   ( PackagesPreferenceDefault (..)
@@ -950,8 +949,11 @@ planPackagesProblems platform cinfo pkgs =
   , let packageProblems = configuredPackageProblems platform cinfo pkg
   , not (null packageProblems)
   ]
-    ++ [ DuplicatePackageSolverId (Graph.nodeKey (Unsafe.head dups)) dups
+    ++ [ DuplicatePackageSolverId (Graph.nodeKey aDup) dups
        | dups <- duplicatesBy (comparing Graph.nodeKey) pkgs
+       , aDup <- case dups of
+          [] -> []
+          (ad : _) -> [ad]
        ]
 
 data PackageProblem

cabal-install/src/Distribution/Client/Init/NonInteractive/Command.hs

@@ -40,7 +40,7 @@ import Distribution.Client.Init.Types
 import Distribution.Client.Compat.Prelude hiding (getLine, head, last, putStr, putStrLn)
 import Prelude ()
 
-import Data.List (head, last)
+import Data.List (last)
 import qualified Data.List.NonEmpty as NEL
 
 import Distribution.CabalSpecVersion (CabalSpecVersion (..))
@@ -340,12 +340,18 @@ packageTypeHeuristics flags = getPackageType flags $ guessPackageType flags
 --   to a default value.
 mainFileHeuristics :: Interactive m => InitFlags -> m HsFilePath
 mainFileHeuristics flags = do
-  appDir <- head <$> appDirsHeuristics flags
+  appDirs <- appDirsHeuristics flags
+  let appDir = case appDirs of
+        [] -> error "impossible: appDirsHeuristics returned empty list of dirs"
+        (appDir' : _) -> appDir'
   getMainFile flags . guessMainFile $ appDir
 
 testMainHeuristics :: Interactive m => InitFlags -> m HsFilePath
 testMainHeuristics flags = do
-  testDir <- head <$> testDirsHeuristics flags
+  testDirs' <- testDirsHeuristics flags
+  let testDir = case testDirs' of
+        [] -> error "impossible: testDirsHeuristics returned empty list of dirs"
+        (testDir' : _) -> testDir'
   guessMainFile testDir
 
 initializeTestSuiteHeuristics :: Interactive m => InitFlags -> m Bool

cabal-install/src/Distribution/Client/Init/NonInteractive/Heuristics.hs

@@ -54,9 +54,9 @@ guessMainFile pkgDir = do
     then do
       files <- filter isMain <$> listFilesRecursive pkgDir
       return $
-        if null files
-          then defaultMainIs
-          else toHsFilePath $ L.head files
+        case files of
+          [] -> defaultMainIs
+          (f : _) -> toHsFilePath f
     else return defaultMainIs
 
 -- | Juggling characters around to guess the desired cabal version based on

cabal-install/src/Distribution/Client/InstallPlan.hs

@@ -72,9 +72,9 @@ module Distribution.Client.InstallPlan
   , reverseDependencyClosure
   ) where
 
-import Distribution.Client.Compat.Prelude hiding (lookup, tail, toList)
+import Distribution.Client.Compat.Prelude hiding (lookup, toList)
 import Distribution.Compat.Stack (WithCallStack)
-import Prelude (tail)
+import Prelude ()
 
 import Distribution.Client.Types hiding (BuildOutcomes)
 import qualified Distribution.PackageDescription as PD
@@ -757,13 +757,13 @@ failed
   -> ([srcpkg], Processing)
 failed plan (Processing processingSet completedSet failedSet) pkgid =
   assert (pkgid `Set.member` processingSet) $
-    assert (all (`Set.notMember` processingSet) (tail newlyFailedIds)) $
-      assert (all (`Set.notMember` completedSet) (tail newlyFailedIds)) $
+    assert (all (`Set.notMember` processingSet) (drop 1 newlyFailedIds)) $
+      assert (all (`Set.notMember` completedSet) (drop 1 newlyFailedIds)) $
         -- but note that some newlyFailed may already be in the failed set
         -- since one package can depend on two packages that both fail and
         -- so would be in the rev-dep closure for both.
         assert (processingInvariant plan processing') $
-          ( map asConfiguredPackage (tail newlyFailed)
+          ( map asConfiguredPackage (drop 1 newlyFailed)
           , processing'
           )
   where

cabal-install/src/Distribution/Client/Upload.hs

@@ -1,7 +1,7 @@
 module Distribution.Client.Upload (upload, uploadDoc, report) where
 
 import Distribution.Client.Compat.Prelude
-import qualified Prelude as Unsafe (head, read, tail)
+import qualified Prelude as Unsafe (read)
 
 import Distribution.Client.HttpUtils
   ( HttpTransport (..)
@@ -155,11 +155,13 @@ uploadDoc verbosity repoCtxt mToken mUsername mPassword isCandidate path = do
         break
           (== '-')
           (reverse (takeFileName path))
-      pkgid = reverse $ Unsafe.tail reversePkgid
+      pkgid = reverse $ drop 1 reversePkgid
   when
     ( reverse reverseSuffix /= "docs.tar.gz"
-        || null reversePkgid
-        || Unsafe.head reversePkgid /= '-'
+        || ( case reversePkgid of
+              [] -> True
+              (c : _) -> c /= '-'
+           )
     )
     $ dieWithException verbosity ExpectedMatchingFileName
 

cabal-install/tests/IntegrationTests2.hs

@@ -80,7 +80,6 @@ import Test.Tasty
 import Test.Tasty.HUnit
 import Test.Tasty.Options
 import Data.Tagged (Tagged(..))
-import qualified Data.List as L
 
 import qualified Data.ByteString as BS
 import Distribution.Client.GlobalFlags (GlobalFlags, globalNix)
@@ -2180,9 +2179,10 @@ testConfigOptionComments = do
   where
     -- | Find lines containing a target string.
     findLineWith :: Bool -> String -> String -> String
-    findLineWith isComment target text
-      | not . null $ findLinesWith isComment target text = removeCommentValue . L.head $ findLinesWith isComment target text
-      | otherwise  = text
+    findLineWith isComment target text =
+      case findLinesWith isComment target text of
+        [] -> text
+        (l : _) -> removeCommentValue l
     findLinesWith :: Bool -> String -> String -> [String]
     findLinesWith isComment target
       | isComment = filter (isInfixOf (" " ++ target ++ ":")) . lines

cabal-install/tests/UnitTests/Distribution/Client/FileMonitor.hs

@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module UnitTests.Distribution.Client.FileMonitor (tests) where
 
 import Distribution.Parsec (simpleParsec)
@@ -31,8 +33,8 @@ tests mtimeChange =
   [ testGroup
       "Structured hashes"
       [ testCase "MonitorStateFile" $ structureHash (Proxy :: Proxy MonitorStateFile) @?= Fingerprint 0xe4108804c34962f6 0x06e94f8fc9e48e13
-      , testCase "MonitorStateGlob" $ structureHash (Proxy :: Proxy MonitorStateGlob) @?= Fingerprint 0xfd8f6be0e8258fe7 0xdb5fac737139bca6
-      , testCase "MonitorStateFileSet" $ structureHash (Proxy :: Proxy MonitorStateFileSet) @?= Fingerprint 0xb745f4ea498389a5 0x70db6adb5078aa27
+      , testCase "MonitorStateGlob" $ structureHash (Proxy :: Proxy MonitorStateGlob) @?= Fingerprint fingerprintStateGlob1 fingerprintStateGlob2
+      , testCase "MonitorStateFileSet" $ structureHash (Proxy :: Proxy MonitorStateFileSet) @?= Fingerprint fingerprintStateFileSet1 fingerprintStateFileSet2
       ]
   , testCase "sanity check mtimes" $ testFileMTimeSanity mtimeChange
   , testCase "sanity check dirs" $ testDirChangeSanity mtimeChange
@@ -85,6 +87,18 @@ tests mtimeChange =
     knownBrokenInWindows msg = case buildOS of
       Windows -> expectFailBecause msg
       _ -> id
+    fingerprintStateGlob1, fingerprintStateGlob2, fingerprintStateFileSet1, fingerprintStateFileSet2 :: Word64
+#if MIN_VERSION_base(4,19,0)
+    fingerprintStateGlob1 = 0xae70229aabb1ba1f
+    fingerprintStateGlob2 = 0xb53ed324c96f0d0d
+    fingerprintStateFileSet1 = 0x8e509e16f973e036
+    fingerprintStateFileSet2 = 0xa23f21d8dc8a2dee
+#else
+    fingerprintStateGlob1 = 0xfd8f6be0e8258fe7
+    fingerprintStateGlob2 = 0xdb5fac737139bca6
+    fingerprintStateFileSet1 = 0xb745f4ea498389a5
+    fingerprintStateFileSet2 = 0x70db6adb5078aa27
+#endif
 
 -- Check the file system behaves the way we expect it to
 

cabal-install/tests/UnitTests/Distribution/Client/InstallPlan.hs

@@ -5,7 +5,6 @@
 module UnitTests.Distribution.Client.InstallPlan (tests) where
 
 import Distribution.Client.Compat.Prelude
-import qualified Prelude as Unsafe (tail)
 
 import Distribution.Client.InstallPlan (GenericInstallPlan, IsUnit)
 import qualified Distribution.Client.InstallPlan as InstallPlan
@@ -285,7 +284,7 @@ arbitraryAcyclicGraph genNRanks genNPerRank edgeChance = do
   nranks <- genNRanks
   rankSizes <- replicateM nranks genNPerRank
   let rankStarts = scanl (+) 0 rankSizes
-      rankRanges = drop 1 (zip rankStarts (Unsafe.tail rankStarts))
+      rankRanges = drop 1 (zip rankStarts (drop 1 rankStarts))
       totalRange = sum rankSizes
   rankEdges <- traverse (uncurry genRank) rankRanges
   return $ buildG (0, totalRange - 1) (concat rankEdges)

cabal-install/tests/UnitTests/Distribution/Client/Targets.hs

@@ -43,7 +43,10 @@ tests =
       "readUserConstraints"
       (uncurry readUserConstraintsTest)
       [ -- First example only.
-        (head exampleStrs, take 1 exampleUcs)
+
+        ( case exampleStrs of (e : _) -> e; _ -> error "empty examples"
+        , take 1 exampleUcs
+        )
       , -- All examples separated by commas.
         (intercalate ", " exampleStrs, exampleUcs)
       ]

cabal-testsuite/src/Test/Cabal/Prelude.hs

@@ -1163,7 +1163,7 @@ findDependencyInStore :: FilePath -- ^store dir
                       -> String -- ^package name prefix
                       -> IO FilePath -- ^package dir
 findDependencyInStore storeDir pkgName = do
-    storeDirForGhcVersion <- head <$> listDirectory storeDir
+    (storeDirForGhcVersion : _) <- listDirectory storeDir
     packageDirs <- listDirectory (storeDir </> storeDirForGhcVersion)
     -- Ideally, we should call 'hashedInstalledPackageId' from 'Distribution.Client.PackageHash'.
     -- But 'PackageHashInputs', especially 'PackageHashConfigInputs', is too hard to construct.

cabal.project

@@ -1,3 +1,5 @@
+import: cabal.project.latest-ghc
+
 packages: Cabal/
 packages: cabal-testsuite/
 packages: Cabal-syntax/

cabal.project.latest-ghc

@@ -0,0 +1,12 @@
+-- Usually, the latest GHC requires a few allow-newer's
+-- for some time after the release. This project file is meant to host these.
+-- The file is supposed to be included in the main project files used for
+-- Cabal development:
+--   - cabal.project (day-to-day development),
+--   - cabal.project.validate (Cabal CI),
+-- Commented out below are the usual suspects. Feel free to add more.
+
+-- NOTE: don't forget to update the compiler version in the conditional
+-- when upgrading to a newer GHC
+if impl(ghc >= 9.8.1)
+    -- allow-newer: windns:*

cabal.project.validate

@@ -1,3 +1,5 @@
+import: cabal.project.latest-ghc
+
 packages: Cabal-syntax/
 packages: Cabal/
 packages: cabal-testsuite/