From 2fb7328a6edf4e81561c2b5153ace898d0740b3e Mon Sep 17 00:00:00 2001
From: Julian Ospald <hasufell@posteo.de>
Date: Sat, 15 Jul 2023 19:07:21 +0800
Subject: [PATCH] Detect hadrian/make automatically, wrt #846

---
 app/ghcup/GHCup/OptParse/Compile.hs | 14 +++++++++----
 lib/GHCup/GHC.hs                    | 31 ++++++++++++++++++++++-------
 lib/GHCup/Types.hs                  |  4 +++-
 3 files changed, 37 insertions(+), 12 deletions(-)

diff --git a/app/ghcup/GHCup/OptParse/Compile.hs b/app/ghcup/GHCup/OptParse/Compile.hs
index f50fb9d..d605597 100644
--- a/app/ghcup/GHCup/OptParse/Compile.hs
+++ b/app/ghcup/GHCup/OptParse/Compile.hs
@@ -76,7 +76,7 @@ data GHCCompileOptions = GHCCompileOptions
   , setCompile   :: Bool
   , ovewrwiteVer :: Maybe Version
   , buildFlavour :: Maybe String
-  , hadrian      :: Bool
+  , buildSystem  :: Maybe BuildSystem
   , isolateDir   :: Maybe FilePath
   }
 
@@ -268,9 +268,15 @@ ghcCompileOpts =
               "Set the compile build flavour (this value depends on the build system type: 'make' vs 'hadrian')"
             )
           )
-    <*> switch
-          (long "hadrian" <> help "Use the hadrian build system instead of make (only git versions seem to be properly supported atm)"
+    <*> (
+         (\b -> if b then Just Hadrian else Nothing) <$> switch
+          (long "hadrian" <> help "Use the hadrian build system instead of make. Tries to detect by default."
           )
+         <|>
+         (\b -> if b then Just Make else Nothing) <$> switch
+          (long "make" <> help "Use the make build system instead of hadrian. Tries to detect by default."
+          )
+        )
     <*> optional
           (option
             (eitherReader isolateParser)
@@ -577,7 +583,7 @@ compile compileCommand settings Dirs{..} runAppState runLogger = do
                     patches
                     addConfArgs
                     buildFlavour
-                    hadrian
+                    buildSystem
                     (maybe GHCupInternal IsolateDir isolateDir)
         GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
         let vi = getVersionInfo targetVer GHC dls
diff --git a/lib/GHCup/GHC.hs b/lib/GHCup/GHC.hs
index df59031..0b05bfe 100644
--- a/lib/GHCup/GHC.hs
+++ b/lib/GHCup/GHC.hs
@@ -764,7 +764,7 @@ compileGHC :: ( MonadMask m
            -> Maybe (Either FilePath [URI])  -- ^ patches
            -> [Text]                   -- ^ additional args to ./configure
            -> Maybe String             -- ^ build flavour
-           -> Bool
+           -> Maybe BuildSystem
            -> InstallDir
            -> Excepts
                 '[ AlreadyInstalled
@@ -793,7 +793,7 @@ compileGHC :: ( MonadMask m
                  ]
                 m
                 GHCTargetVersion
-compileGHC targetGhc crossTarget ov bstrap jobs mbuildConfig patches aargs buildFlavour hadrian installDir
+compileGHC targetGhc crossTarget ov bstrap jobs mbuildConfig patches aargs buildFlavour buildSystem installDir
   = do
     PlatformRequest { .. } <- lift getPlatformReq
     GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
@@ -927,11 +927,28 @@ compileGHC targetGhc crossTarget ov bstrap jobs mbuildConfig patches aargs build
     (mBindist, bmk) <- liftE $ runBuildAction
       tmpUnpack
       (do
-        b <- if hadrian
-             -- 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
+        -- prefer 'tver', because the real version carries out compatibility checks
+        -- we don't want the user to do funny things with it
+        let doHadrian = compileHadrianBindist (fromMaybe installVer tver) (fromGHCupPath workdir) ghcdir
+            doMake    = compileMakeBindist (fromMaybe installVer tver) (fromGHCupPath workdir) ghcdir
+        b <- case buildSystem of
+               Just Hadrian -> do
+                 lift $ logInfo "Requested to use Hadrian"
+                 liftE doHadrian
+               Just Make -> do
+                 lift $ logInfo "Requested to use Make"
+                 doMake
+               Nothing -> do
+                 supportsHadrian <- liftE $ catchE @HadrianNotFound @'[HadrianNotFound] @'[] (\_ -> return False)
+                                      $ fmap (const True)
+                                      $ findHadrianFile (fromGHCupPath workdir)
+                 if supportsHadrian
+                 then do
+                   lift $ logInfo "Detected Hadrian"
+                   liftE doHadrian
+                 else do
+                   lift $ logInfo "Detected Make"
+                   doMake
         bmk <- liftIO $ handleIO (\_ -> pure "") $ B.readFile (build_mk $ fromGHCupPath workdir)
         pure (b, bmk)
       )
diff --git a/lib/GHCup/Types.hs b/lib/GHCup/Types.hs
index e67e720..e71b2a5 100644
--- a/lib/GHCup/Types.hs
+++ b/lib/GHCup/Types.hs
@@ -719,4 +719,6 @@ instance Pretty ToolVersion where
 
 
 
-
+data BuildSystem = Hadrian
+                 | Make
+  deriving (Show, Eq)