Allow building newer GHCs from git

The user will have to pass --overwrite-version=<ver> because
we can't discover the GHC version from git anymore.

https://gitlab.haskell.org/ghc/ghc/-/issues/22322

app/ghcup/BrickMain.hs

@@ -13,7 +13,6 @@ import           GHCup.Errors
 import           GHCup.Types.Optics ( getDirs )
 import           GHCup.Types         hiding ( LeanAppState(..) )
 import           GHCup.Utils
-import           GHCup.OptParse.Common (logGHCPostRm)
 import           GHCup.Prelude ( decUTF8Safe )
 import           GHCup.Prelude.File
 import           GHCup.Prelude.Logger
@@ -555,7 +554,6 @@ del' _ (_, ListResult {..}) = do
     )
     >>= \case
           VRight vi -> do
-            logGHCPostRm (mkTVer lVer)
             forM_ (_viPostRemove =<< vi) $ \msg ->
               logInfo msg
             pure $ Right ()

app/ghcup/GHCup/OptParse/Common.hs

@@ -25,7 +25,6 @@ import           Control.DeepSeq
 import           Control.Concurrent
 import           Control.Concurrent.Async
 import           Control.Exception.Safe
-import           Control.Monad.Identity (Identity(..))
 #if !MIN_VERSION_base(4,13,0)
 import           Control.Monad.Fail             ( MonadFail )
 #endif
@@ -65,7 +64,6 @@ import qualified Text.Megaparsec               as MP
 import qualified System.FilePath.Posix         as FP
 import GHCup.Version
 import Control.Exception (evaluate)
-import qualified Cabal.Config            as CC
 
 
     -------------
@@ -791,12 +789,3 @@ checkForUpdates = do
   pure $ catMaybes (ghcup:otherTools)
  where
   forMM a f = fmap join $ forM a f
-
-
-logGHCPostRm :: (MonadReader env m, HasLog env, MonadIO m) => GHCTargetVersion -> m ()
-logGHCPostRm ghcVer = do
-  cabalStore <- liftIO $ handleIO (\_ -> if isWindows then pure "C:\\cabal\\store" else pure "~/.cabal/store")
-    (runIdentity . CC.cfgStoreDir <$> CC.readConfig)
-  let storeGhcDir = cabalStore </> ("ghc-" <> T.unpack (prettyVer $ _tvVersion ghcVer))
-  logInfo $ T.pack $ "After removing GHC you might also want to clean up your cabal store at: " <> storeGhcDir
-

app/ghcup/GHCup/OptParse/Rm.hs

@@ -175,8 +175,8 @@ rm rmCommand runAppState runLogger = case rmCommand of
       )
       >>= \case
             VRight vi -> do
-              runLogger $ logGHCPostRm ghcVer
-              postRmLog vi
+              forM_ (_viPostRemove =<< vi) $ \msg ->
+                runLogger $ logInfo msg
               pure ExitSuccess
             VLeft  e -> do
               runLogger $ logError $ T.pack $ prettyShow e
@@ -191,7 +191,8 @@ rm rmCommand runAppState runLogger = case rmCommand of
       )
       >>= \case
             VRight vi -> do
-              postRmLog vi
+              forM_ (_viPostRemove =<< vi) $ \msg ->
+                runLogger $ logInfo msg
               pure ExitSuccess
             VLeft  e -> do
               runLogger $ logError $ T.pack $ prettyShow e
@@ -206,7 +207,8 @@ rm rmCommand runAppState runLogger = case rmCommand of
       )
       >>= \case
             VRight vi -> do
-              postRmLog vi
+              forM_ (_viPostRemove =<< vi) $ \msg ->
+                runLogger $ logInfo msg
               pure ExitSuccess
             VLeft  e -> do
               runLogger $ logError $ T.pack $ prettyShow e
@@ -221,12 +223,10 @@ rm rmCommand runAppState runLogger = case rmCommand of
       )
       >>= \case
             VRight vi -> do
-              postRmLog vi
+              forM_ (_viPostRemove =<< vi) $ \msg ->
+                runLogger $ logInfo msg
               pure ExitSuccess
             VLeft  e -> do
               runLogger $ logError $ T.pack $ prettyShow e
               pure $ ExitFailure 15
 
-  postRmLog vi =
-    forM_ (_viPostRemove =<< vi) $ \msg ->
-      runLogger $ logInfo msg

ghcup.cabal

@@ -247,7 +247,6 @@ executable ghcup
     , base                  >=4.12     && <5
     , bytestring            >=0.10     && <0.12
     , cabal-plan            ^>=0.7.2
-    , cabal-install-parsers >=0.4.5
     , containers            ^>=0.6
     , deepseq               ^>=1.4
     , directory             ^>=1.3.6.0

lib/GHCup/GHC.hs

@@ -676,7 +676,7 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patches aargs buildFlavour hadr
                          (view dlSubdir dlInfo)
         liftE $ applyAnyPatch patches (fromGHCupPath workdir)
 
-        pure (workdir, tmpUnpack, tver)
+        pure (workdir, tmpUnpack, Just tver)
 
       RemoteDist uri -> do
         lift $ logDebug $ "Requested to compile (from uri): " <> T.pack (show uri)
@@ -694,12 +694,13 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patches aargs buildFlavour hadr
                            execBlank
                            regex
             )
-          tver <- liftE $ getGHCVer (appendGHCupPath tmpUnpack (takeDirectory bootFile))
+          tver <- liftE $ catchAllE @_ @'[ProcessError, ParseError] @'[] (\_ -> pure Nothing) $ fmap Just $ getGHCVer
+            (appendGHCupPath tmpUnpack (takeDirectory bootFile))
           pure (bootFile, tver)
 
         let workdir = appendGHCupPath tmpUnpack (takeDirectory bf)
 
-        pure (workdir, tmpUnpack, mkTVer tver)
+        pure (workdir, tmpUnpack, mkTVer <$> tver)
 
       -- clone from git
       GitDist GitBranch{..} -> do
@@ -745,20 +746,23 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patches aargs buildFlavour hadr
           liftE $ applyAnyPatch patches (fromGHCupPath tmpUnpack)
 
           -- bootstrap
-          tver <- liftE $ getGHCVer tmpUnpack
+          tver <- liftE $ catchAllE @_ @'[ProcessError, ParseError] @'[] (\_ -> pure Nothing) $ fmap Just $ getGHCVer
+            tmpUnpack
           liftE $ catchWarn $ lEM @_ @'[ProcessError] $ darwinNotarization _rPlatform (fromGHCupPath tmpUnpack)
           lift $ logInfo $ "Examining git ref " <> T.pack ref <> "\n  " <>
-                           "GHC version (from Makefile): " <> prettyVer tver <>
+                           "GHC version (from Makefile): " <> T.pack (show (prettyVer <$> tver)) <>
                            (if not shallow_clone then "\n  " <> "'git describe' output: " <> fromJust git_describe else mempty) <>
                            (if isCommitHash ref then mempty else "\n  " <> "commit hash: " <> chash)
           liftIO $ threadDelay 5000000 -- give the user a sec to intervene
 
           pure tver
 
-        pure (tmpUnpack, tmpUnpack, GHCTargetVersion Nothing tver)
+        pure (tmpUnpack, tmpUnpack, mkTVer <$> tver)
     -- the version that's installed may differ from the
     -- compiled version, so the user can overwrite it
-    let installVer = maybe tver (\ov' -> tver { _tvVersion = ov' }) ov
+    installVer <- if | Just ov'   <- ov   -> pure (mkTVer ov')
+                     | Just tver' <- tver -> pure tver'
+                     | otherwise          -> fail "Newer GHCs don't support discovering the version in git. Complain to GHC devs: https://gitlab.haskell.org/ghc/ghc/-/issues/22322"
 
     alreadyInstalled <- lift $ ghcInstalled installVer
     alreadySet <- fmap (== Just installVer) $ lift $ ghcSet (_tvTarget installVer)
@@ -781,8 +785,10 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patches aargs buildFlavour hadr
       tmpUnpack
       (do
         b <- if hadrian
-             then compileHadrianBindist tver (fromGHCupPath workdir) ghcdir
-             else compileMakeBindist tver (fromGHCupPath workdir) ghcdir
+             -- prefer 'tver', because the real version carries out compatibility checks
+             -- we don't want the user to do funny things with it
+             then compileHadrianBindist (fromMaybe installVer tver) (fromGHCupPath workdir) ghcdir
+             else compileMakeBindist (fromMaybe installVer tver) (fromGHCupPath workdir) ghcdir
         bmk <- liftIO $ handleIO (\_ -> pure "") $ B.readFile (build_mk $ fromGHCupPath workdir)
         pure (b, bmk)
       )
@@ -826,14 +832,14 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patches aargs buildFlavour hadr
                , MonadThrow m
                )
             => GHCupPath
-            -> Excepts '[ProcessError] m Version
+            -> Excepts '[ProcessError, ParseError] m Version
   getGHCVer tmpUnpack = do
     lEM $ execWithGhcEnv "python3" ["./boot"] (Just $ fromGHCupPath tmpUnpack) "ghc-bootstrap"
     lEM $ execWithGhcEnv "sh" ["./configure"] (Just $ fromGHCupPath tmpUnpack) "ghc-bootstrap"
     CapturedProcess {..} <- lift $ makeOut
       ["show!", "--quiet", "VALUE=ProjectVersion" ] (Just $ fromGHCupPath tmpUnpack)
     case _exitCode of
-      ExitSuccess -> throwEither . MP.parse ghcProjectVersion "" . T.pack . stripNewlineEnd . T.unpack . decUTF8Safe' $ _stdOut
+      ExitSuccess -> either (throwE . ParseError . show) pure . MP.parse ghcProjectVersion "" . T.pack . stripNewlineEnd . T.unpack . decUTF8Safe' $ _stdOut
       ExitFailure c -> throwE $ NonZeroExit c "make" ["show!", "--quiet", "VALUE=ProjectVersion" ]
 
   defaultConf =