Fix disabling installation of stack

Fixes #429

CHANGELOG.md

@@ -1,5 +1,36 @@
 # Revision history for ghcup
 
+## 0.1.18.1 -- 2022-08-06
+
+* fix sdist and unbreak hackage, wrt [#399](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/399)
+
+## 0.1.18.0 -- 2022-07-30
+
+* Fix tui set wrt [#266](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/266) by Arjun Kathuria
+    - Ask the user to install the tool via prompt when setting an non-installed version
+* improvements to safe (un-)installations
+    - bindists that don't support `make DESTDIR=/some/tmp/dir install` are now unsupported
+    - installed GHC files are now recorded to avoid use of `removePathForcibly`
+    - internally uses a newtype wrapper for user-input paths and restrict destructive operations to validated paths
+* Add `--disable-ld-override` for darwin bindists wrt #391
+* Allow passing bindist configure args wrt #377
+* use of `TMPDIR` is dropped... now uses an internal tmp dir `~/.ghcup/tmp`
+* improvements to error handling and warnings
+* Require --isolate to have an absolute directory, fixes #367
+* Fix mingw PATH handling wrt #371
+* Add --mingw-path switch to `ghcup run`
+* Fix `ghcup run` on windows, fixes #375
+* Improve `ghcup compile <hls|ghc>`
+    - short hashes now work
+    - print the long hash in addition to the detected version
+* Improve `ghcup compile hls`
+    - add `--git-describe-version` switch as an alternative to `--overwrite-version`
+    - Allow to build HLS from hackage (now is the default)
+	- Allow to run 'cabal update' automatically before the HLS build
+	- Fix parser and completer for 'ghcup compile hls --version'
+* Improve `ghcup compile ghc`
+    - Allow to build from arbitrary GHC source dists
+
 ## 0.1.17.10 -- 2022-05-12
 
 * windows hotfix (hackage-only release)

app/ghcup/BrickMain.hs

@@ -17,6 +17,7 @@ import           GHCup.Prelude ( decUTF8Safe )
 import           GHCup.Prelude.File
 import           GHCup.Prelude.Logger
 import           GHCup.Prelude.Process
+import           GHCup.Prompts
 
 import           Brick
 import           Brick.Widgets.Border
@@ -52,6 +53,8 @@ import           Text.PrettyPrint.HughesPJClass ( prettyShow )
 import           URI.ByteString
 
 import qualified Data.Text                     as T
+import qualified Data.Text.Lazy.Builder        as B
+import qualified Data.Text.Lazy                as L
 import qualified Graphics.Vty                  as Vty
 import qualified Data.Vector                   as V
 import System.Environment (getExecutablePath)
@@ -98,7 +101,7 @@ keyHandlers KeyBindings {..} =
   [ (bQuit, const "Quit"     , halt)
   , (bInstall, const "Install"  , withIOAction install')
   , (bUninstall, const "Uninstall", withIOAction del')
-  , (bSet, const "Set"      , withIOAction ((liftIO .) . set'))
+  , (bSet, const "Set"      , withIOAction set')
   , (bChangelog, const "ChangeLog", withIOAction changelog')
   , ( bShowAllVersions
     , \BrickSettings {..} ->
@@ -486,9 +489,12 @@ install' _ (_, ListResult {..}) = do
             <> "Also check the logs in ~/.ghcup/logs"
 
 
-set' :: BrickState -> (Int, ListResult) -> IO (Either String ())
-set' _ (_, ListResult {..}) = do
-  settings <- readIORef settings'
+set' :: (MonadReader AppState m, MonadIO m, MonadThrow m, MonadFail m, MonadMask m, MonadUnliftIO m)
+     => BrickState
+     -> (Int, ListResult)
+     -> m (Either String ())
+set' bs input@(_, ListResult {..}) = do
+  settings <- liftIO $ readIORef settings'
 
   let run =
         flip runReaderT settings
@@ -504,7 +510,28 @@ set' _ (_, ListResult {..}) = do
     )
     >>= \case
           VRight _ -> pure $ Right ()
-          VLeft  e -> pure $ Left (prettyShow e)
+          VLeft  e -> case e of
+            (V (NotInstalled tool _)) -> do
+              promptAnswer <- getUserPromptResponse userPrompt
+              case promptAnswer of
+                PromptYes -> do
+                  res <- install' bs input
+                  case res of
+                    (Left err) -> pure $ Left err
+                    (Right _) -> do
+                      logInfo "Setting now..."
+                      set' bs input
+
+                PromptNo -> pure $ Left (prettyShow e)
+              where
+                userPrompt = L.toStrict . B.toLazyText . B.fromString $
+                  "This Version of "
+                  <> show tool
+                  <> " you are trying to set is not installed.\n"
+                  <> "Would you like to install it first? [Y/N]: "
+
+            _ -> pure $ Left (prettyShow e)
+
 
 
 del' :: (MonadReader AppState m, MonadIO m, MonadFail m, MonadMask m, MonadUnliftIO m)

app/ghcup/GHCup/OptParse/Common.hs

@@ -452,9 +452,11 @@ tagCompleter tool add = listIOCompleter $ do
       pure $ nub $ (add ++) $ fmap tagToString allTags
     VLeft _ -> pure  (nub $ ["recommended", "latest"] ++ add)
 
-
 versionCompleter :: Maybe ListCriteria -> Tool -> Completer
-versionCompleter criteria tool = listIOCompleter $ do
+versionCompleter criteria tool = versionCompleter' criteria tool (const True)
+
+versionCompleter' :: Maybe ListCriteria -> Tool -> (Version -> Bool) -> Completer
+versionCompleter' criteria tool filter' = listIOCompleter $ do
   dirs' <- liftIO getAllDirs
   let loggerConfig = LoggerConfig
         { lcPrintDebug   = False
@@ -483,7 +485,7 @@ versionCompleter criteria tool = listIOCompleter $ do
           runEnv = flip runReaderT appState
 
       installedVersions <- runEnv $ listVersions (Just tool) criteria
-      return $ T.unpack . prettyVer . lVer <$> installedVersions
+      return $ fmap (T.unpack . prettyVer) . filter filter' . fmap lVer $ installedVersions
 
 
 toolDlCompleter :: Tool -> Completer

app/ghcup/GHCup/OptParse/Compile.hs

@@ -12,6 +12,8 @@ module GHCup.OptParse.Compile where
 
 
 import           GHCup
+import qualified GHCup.GHC as GHC
+import qualified GHCup.HLS as HLS
 import           GHCup.Errors
 import           GHCup.Types
 import           GHCup.Types.Optics
@@ -30,7 +32,8 @@ import           Control.Monad.Trans.Resource
 import           Data.Bifunctor
 import           Data.Functor
 import           Data.Maybe
-import           Data.Versions                  ( Version, prettyVer, version )
+import           Data.Versions                  ( Version, prettyVer, version, pvp )
+import qualified Data.Versions as V
 import           Data.Text                      ( Text )
 import           Haskus.Utils.Variant.Excepts
 import           Options.Applicative     hiding ( style )
@@ -41,7 +44,7 @@ import           Text.PrettyPrint.HughesPJClass ( prettyShow )
 
 import           URI.ByteString          hiding ( uriParser )
 import qualified Data.Text                     as T
-import Control.Exception.Safe (MonadMask)
+import Control.Exception.Safe (MonadMask, displayException)
 import System.FilePath (isPathSeparator)
 import Text.Read (readEither)
 
@@ -64,7 +67,7 @@ data CompileCommand = CompileGHC GHCCompileOptions
 
 
 data GHCCompileOptions = GHCCompileOptions
-  { targetGhc    :: Either Version GitBranch
+  { targetGhc    :: GHC.GHCVer Version
   , bootstrapGhc :: Either Version FilePath
   , jobs         :: Maybe Int
   , buildConfig  :: Maybe FilePath
@@ -78,10 +81,12 @@ data GHCCompileOptions = GHCCompileOptions
   , isolateDir   :: Maybe FilePath
   }
 
+
 data HLSCompileOptions = HLSCompileOptions
-  { targetHLS    :: Either Version GitBranch
+  { targetHLS    :: HLS.HLSVer
   , jobs         :: Maybe Int
   , setCompile   :: Bool
+  , updateCabal  :: Bool
   , ovewrwiteVer :: Either Bool Version
   , isolateDir   :: Maybe FilePath
   , cabalProject :: Maybe (Either FilePath URI)
@@ -149,10 +154,10 @@ Examples:
   These need to be available in PATH prior to compilation.
 
 Examples:
-  # compile 1.7.0.0 for ghc 8.10.5 and 8.10.7, passing '--allow-newer' to cabal
-  ghcup compile hls -v 1.7.0.0 -j 12 --ghc 8.10.5 --ghc 8.10.7 -- --allow-newer
-  # compile from master for ghc 9.2.3 and use 'git describe' to name the binary
-  ghcup compile hls -g master --git-describe-version --ghc 9.2.3
+  # compile 1.7.0.0 from hackage for 8.10.7, running 'cabal update' before the build
+  ghcup compile hls --version 1.7.0.0 --ghc 8.10.7 --cabal-update
+  # compile from master for ghc 9.2.3 using 'git describe' to name the binary and ignore the pinned index state
+  ghcup compile hls -g master --git-describe-version --ghc 9.2.3 -- --index-state=@(date '+%s')
   # compile a specific commit for ghc 9.2.3 and set a specifc version for the binary name
   ghcup compile hls -g a32db0b -o 1.7.0.0-p1 --ghc 9.2.3|]
 
@@ -160,7 +165,7 @@ Examples:
 ghcCompileOpts :: Parser GHCCompileOptions
 ghcCompileOpts =
   GHCCompileOptions
-    <$> ((Left <$> option
+    <$> ((GHC.SourceDist <$> option
           (eitherReader
             (first (const "Not a valid version") . version . T.pack)
           )
@@ -169,7 +174,7 @@ ghcCompileOpts =
             <> (completer $ versionCompleter Nothing GHC)
           )
           ) <|>
-          (Right <$> (GitBranch <$> option
+          (GHC.GitDist <$> (GitBranch <$> option
           str
           (short 'g' <> long "git-ref" <> metavar "GIT_REFERENCE" <> help
             "The git commit/branch/ref to build from"
@@ -178,7 +183,18 @@ ghcCompileOpts =
             short 'r' <> long "repository" <> metavar "GIT_REPOSITORY" <> help "The git repository to build from (defaults to GHC upstream)"
             <> completer (gitFileUri ["https://gitlab.haskell.org/ghc/ghc.git"])
             ))
-          )))
+          ))
+          <|>
+          (
+           GHC.RemoteDist <$> (option
+            (eitherReader uriParser)
+            (long "remote-source-dist" <> metavar "URI" <> help
+              "URI (https/http/file) to a GHC source distribution"
+              <> completer fileUri
+            )
+          )
+          )
+          )
     <*> option
           (eitherReader
             (\x ->
@@ -270,16 +286,17 @@ ghcCompileOpts =
 hlsCompileOpts :: Parser HLSCompileOptions
 hlsCompileOpts =
   HLSCompileOptions
-    <$> ((Left <$> option
+    <$> ((HLS.HackageDist <$> option
           (eitherReader
-            (first (const "Not a valid version") . version . T.pack)
+            ((>>= first displayException . V.version . V.prettyPVP) . first (const "Not a valid PVP version") . pvp . T.pack)
           )
           (short 'v' <> long "version" <> metavar "VERSION" <> help
-            "The tool version to compile"
-            <> (completer $ versionCompleter Nothing HLS)
+            "The version to compile (pulled from hackage)"
+            <> (completer $ versionCompleter' Nothing HLS (either (const False) (const True) . V.pvp . V.prettyVer))
           )
-          ) <|>
-          (Right <$> (GitBranch <$> option
+          )
+          <|>
+          (HLS.GitDist <$> (GitBranch <$> option
           str
           (short 'g' <> long "git-ref" <> metavar "GIT_REFERENCE" <> help
             "The git commit/branch/ref to build from (accepts anything 'git checkout' accepts)"
@@ -287,7 +304,28 @@ hlsCompileOpts =
           optional (option str (short 'r' <> long "repository" <> metavar "GIT_REPOSITORY" <> help "The git repository to build from (defaults to HLS upstream)"
             <> completer (gitFileUri ["https://github.com/haskell/haskell-language-server.git"])
           ))
-          )))
+          ))
+          <|>
+          (HLS.SourceDist <$> (option
+            (eitherReader
+              (first (const "Not a valid version") . version . T.pack)
+            )
+          (long "source-dist" <> metavar "VERSION" <> help
+            "The version to compile (pulled from packaged git sources)"
+            <> (completer $ versionCompleter Nothing HLS)
+          )
+          ))
+          <|>
+          (
+           HLS.RemoteDist <$> (option
+            (eitherReader uriParser)
+            (long "remote-source-dist" <> metavar "URI" <> help
+              "URI (https/http/file) to a HLS source distribution"
+              <> completer fileUri
+            )
+          )
+          )
+          )
     <*> optional
           (option
             (eitherReader (readEither @Int))
@@ -297,6 +335,7 @@ hlsCompileOpts =
             )
           )
     <*> fmap (fromMaybe True) (invertableSwitch "set" Nothing True (help "Don't set as active version after install"))
+    <*> switch (long "cabal-update" <> help "Run 'cabal update' before the build")
     <*>
          (
           (Right <$> option
@@ -468,7 +507,7 @@ compile compileCommand settings Dirs{..} runAppState runLogger = do
     (CompileHLS HLSCompileOptions { .. }) -> do
       runCompileHLS runAppState (do
         case targetHLS of
-          Left targetVer -> do
+          HLS.SourceDist targetVer -> do
             GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
             let vi = getVersionInfo targetVer HLS dls
             forM_ (_viPreCompile =<< vi) $ \msg -> do
@@ -476,7 +515,7 @@ compile compileCommand settings Dirs{..} runAppState runLogger = do
               lift $ logInfo
                 "...waiting for 5 seconds, you can still abort..."
               liftIO $ threadDelay 5000000 -- for compilation, give the user a sec to intervene
-          Right _ -> pure ()
+          _ -> pure ()
         ghcs <- liftE $ forM targetGHCs (\ghc -> fmap (_tvVersion . fst) . fromVersion (Just ghc) $ GHC)
         targetVer <- liftE $ compileHLS
                     targetHLS
@@ -486,6 +525,7 @@ compile compileCommand settings Dirs{..} runAppState runLogger = do
                     (maybe GHCupInternal IsolateDir isolateDir)
                     cabalProject
                     cabalProjectLocal
+                    updateCabal
                     patches
                     cabalArgs
         GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
@@ -519,7 +559,7 @@ compile compileCommand settings Dirs{..} runAppState runLogger = do
     (CompileGHC GHCCompileOptions {..}) ->
       runCompileGHC runAppState (do
         case targetGhc of
-          Left targetVer -> do
+          GHC.SourceDist targetVer -> do
             GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
             let vi = getVersionInfo targetVer GHC dls
             forM_ (_viPreCompile =<< vi) $ \msg -> do
@@ -527,9 +567,12 @@ compile compileCommand settings Dirs{..} runAppState runLogger = do
               lift $ logInfo
                 "...waiting for 5 seconds, you can still abort..."
               liftIO $ threadDelay 5000000 -- for compilation, give the user a sec to intervene
-          Right _ -> pure ()
+          _ -> pure ()
         targetVer <- liftE $ compileGHC
-                    (first (GHCTargetVersion crossTarget) targetGhc)
+                    ((\case
+                        GHC.SourceDist v -> GHC.SourceDist $ GHCTargetVersion crossTarget v
+                        GHC.GitDist g -> GHC.GitDist g
+                        GHC.RemoteDist r -> GHC.RemoteDist r) targetGhc)
                     ovewrwiteVer
                     bootstrapGhc
                     jobs

app/ghcup/GHCup/OptParse/Install.hs

@@ -171,7 +171,7 @@ Examples:
   ghcup install ghc 8.10.2
 
   # install GHC head fedora bindist
-  ghcup install ghc -u https://gitlab.haskell.org/api/v4/projects/1/jobs/artifacts/master/raw/ghc-x86_64-fedora27-linux.tar.xz?job=validate-x86_64-linux-fedora27 head|]
+  ghcup install ghc -u 'https://gitlab.haskell.org/ghc/ghc/-/jobs/artifacts/master/raw/ghc-x86_64-linux-fedora33-release.tar.xz?job=x86_64-linux-fedora33-release' head|]
 
 
 installOpts :: Maybe Tool -> Parser InstallOptions
@@ -546,4 +546,3 @@ install installCommand settings getAppState' runLogger = case installCommand of
                 logError $ T.pack $ prettyShow e
                 logError $ "Also check the logs in " <> T.pack (fromGHCupPath logsDir)
               pure $ ExitFailure 4
-

app/ghcup/Main.hs

@@ -14,6 +14,8 @@ module Main where
 import           BrickMain                    ( brickMain )
 #endif
 
+import qualified GHCup.GHC as GHC
+import qualified GHCup.HLS as HLS
 import           GHCup.OptParse
 
 import           GHCup.Download
@@ -338,11 +340,13 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
   alreadyInstalling (Install (Left (InstallStack InstallOptions{..})))   (Stack, ver) = cmp' Stack instVer ver
   alreadyInstalling (Compile (CompileGHC GHCCompileOptions{ ovewrwiteVer = Just over }))
     (GHC, ver)   = cmp' GHC (Just $ GHCVersion (mkTVer over)) ver
-  alreadyInstalling (Compile (CompileGHC GHCCompileOptions{ targetGhc = Left tver }))
+  alreadyInstalling (Compile (CompileGHC GHCCompileOptions{ targetGhc = GHC.SourceDist tver }))
     (GHC, ver)   = cmp' GHC (Just $ ToolVersion tver) ver
   alreadyInstalling (Compile (CompileHLS HLSCompileOptions{ ovewrwiteVer = Right over }))
     (HLS, ver)   = cmp' HLS (Just $ ToolVersion over) ver
-  alreadyInstalling (Compile (CompileHLS HLSCompileOptions{ targetHLS = Left tver }))
+  alreadyInstalling (Compile (CompileHLS HLSCompileOptions{ targetHLS = HLS.SourceDist tver }))
+    (HLS, ver)   = cmp' HLS (Just $ ToolVersion tver) ver
+  alreadyInstalling (Compile (CompileHLS HLSCompileOptions{ targetHLS = HLS.HackageDist tver }))
     (HLS, ver)   = cmp' HLS (Just $ ToolVersion tver) ver
   alreadyInstalling (Upgrade {}) (GHCup, _) = pure True
   alreadyInstalling _ _ = pure False

docs/guide.md

@@ -4,7 +4,7 @@ This is a more in-depth guide specific to GHCup. `ghcup --help` is your friend.
 
 ## Basic usage
 
-For the simple interactive TUI (not available on windows), run:
+For the simple, interactive, text-based user interface (TUI) (not available on windows), run:
 
 ```sh
 ghcup tui
@@ -186,6 +186,51 @@ url-source:
 
 # More on installation
 
+## Customisation of the installation scripts
+
+The scripts offered to install GHCup are available here:
+
+* [bootstrap-haskell](https://gitlab.haskell.org/haskell/ghcup-hs/-/blob/master/scripts/bootstrap/bootstrap-haskell#L7)
+  for Unix-like operating systems
+* [bootstrap-haskell.ps1](https://gitlab.haskell.org/haskell/ghcup-hs/-/blob/master/scripts/bootstrap/bootstrap-haskell.ps1#L17)
+  for Windows (PowerShell). This will, in turn, run the final bootstrap script
+  (by default, that for the Unix-like operating systems).
+
+The effect of the scripts can be customised by setting one or more
+`BOOTSTRAP_HASKELL_*` environment variables (as set out in the first script)
+and, in the case of Windows, by specifying parameters (as set out in the
+PowerShell script).
+
+For example, you can toggle:
+
+* non-interactive installation
+* a more verbose installation
+* whether to install only GHCup (and, on Windows, MSYS2)
+* not to trigger the upgrade of GHCup
+* whether to install the latest version of HLS
+* whether to install the latest version of Stack
+* whether to respect the XDG Base Directory Specification
+* whether to adjust (prepend) the PATH in `bashrc`
+* on Windows, whether to adjust MINGW paths in `cabal.config`
+
+You can also specify:
+
+* the GHC version to install
+* the Cabal version to install
+* which downloader to use (the default is `curl`)
+* the base URL for the download of the GHCup binary distribution
+
+On Windows, you can also use the parameters to:
+
+* toggle whether to overwrite a previous installation
+* specify the GHCup installation root directory
+* specify the Cabal root directory
+* specify the directory of an existing installation of MSYS2 (for example,
+  the one supplied by Stack)
+* specify the URL of the final bootstrap script
+* toggle whether to run the final bootstrap script via `bash` (instead of in a
+  new MSYS2 shell)
+
 ## Installing custom bindists
 
 There are a couple of good use cases to install custom bindists:
@@ -193,7 +238,8 @@ There are a couple of good use cases to install custom bindists:
 1. manually built bindists (e.g. with patches)
     - example: `ghcup install ghc -u 'file:///home/mearwald/tmp/ghc-eff-patches/ghc-8.10.2-x86_64-deb10-linux.tar.xz' 8.10.2-eff`
 2. GHC head CI bindists
-    - example: `ghcup install ghc -u 'https://gitlab.haskell.org/api/v4/projects/1/jobs/artifacts/master/raw/ghc-x86_64-fedora27-linux.tar.xz?job=validate-x86_64-linux-fedora27' head`
+    - example specifying a branch (`master`): `ghcup install ghc -u 'https://gitlab.haskell.org/ghc/ghc/-/jobs/artifacts/master/raw/ghc-x86_64-linux-fedora33-release.tar.xz?job=x86_64-linux-fedora33-release' head`
+    - example specifying a job id (`1129565`): `ghcup install ghc -u ' https://gitlab.haskell.org/api/v4/projects/1/jobs/1129565/artifacts/ghc-x86_64-linux-alpine3_12-validate+fully_static.tar.xz' mr7847`
 3. DWARF bindists
     - example: `ghcup install ghc -u 'https://downloads.haskell.org/~ghc/8.10.2/ghc-8.10.2-x86_64-deb10-linux-dwarf.tar.xz' 8.10.2-dwarf`
 
@@ -202,7 +248,9 @@ and produce the binaries `ghc-8.10.2-eff` and `ghc-head` respectively.
 GHCup always needs to know which version the bindist corresponds to (this is not automatically
 detected).
 
-## Compiling GHC from source
+## Compiling from source
+
+### GHC
 
 Compiling from source is supported for both source tarballs and arbitrary git refs. See `ghcup compile ghc --help`
 for a list of all available options.
@@ -214,6 +262,64 @@ Common `build.mk` options are explained [here](https://gitlab.haskell.org/ghc/gh
 
 Make sure your system meets all the [prerequisites](https://gitlab.haskell.org/ghc/ghc/-/wikis/building/preparation).
 
+### HLS
+
+There are 3 main ways to compile HLS from source.
+
+1. from hackage (should have up to date version bounds)
+    - `ghcup compile hls --version 1.7.0.0 --ghc 9.2.3`
+2. from git (allows to build latest sources and PRs)
+    - `ghcup compile hls --git-ref master --ghc 9.2.3`
+    - `ghcup compile hls --git-ref a32db0b --ghc 9.2.3`
+    - `ghcup compile hls --git-ref 1.7.0.0 --ghc 9.2.3`
+3. from source distribution that's packaged during release from the corresponding git sources
+    - `ghcup compile hls --source-dist 1.7.0.0 --ghc 9.2.3`
+
+All these use `cabal v2-install` under the hood, so all build components are cached.
+You can pass arbitrary arguments to cabal, e.g. set the index state like so:
+
+```sh
+ghcup compile hls --git-ref master --ghc 9.2.3 -- --index-state=2022-06-12T00:00:00Z --allow-newer
+```
+
+You can pass `--ghc <ver>` multiple times to install for many GHCs at once.
+
+When building from git sources, ghcup will auto-detect the HLS version that the git commit corresponds to
+from the `haskell-language-server.cabal` file. This version might not have been updated since the last release.
+If you want to avoid overwriting the existing installed HLS version, you can instruct ghcup to use `git describe`
+to set the HLS version instead:
+
+```sh
+ghcup compile hls --git-ref master --ghc 9.2.3 --git-describe-version
+```
+
+You can also set the version explicitly:
+
+```sh
+ghcup compile hls --git-ref master --ghc 9.2.3 --overwrite-version 1.7.0.0-p1
+```
+
+To instruct cabal to run `cabal update` before building, run `ghcup compile hls --version 1.7.0.0 --ghc 9.2.3 --cabal-update`
+
+As always, check `ghcup compile hls --help`.
+
+#### Updating HLS for a new GHC version
+
+First try to build from hackage with some tricks:
+
+```sh
+ghcup compile hls --version 1.7.0.0 --ghc 9.2.4 --cabal-update -- --allow-newer --index-state=2022-06-12T00:00:00Z
+```
+
+This augments the currently installed 1.7.0.0 official bindists in ghcup with new GHC versions support.
+
+If that fails (since `--allow-newer` is quite brutal), you can install from HLS master branch (which may contain new fixes) like so:
+```
+ghcup compile hls --git-ref master --git-describe-version --ghc 8.10.7 --ghc 9.2.4 --cabal-update
+```
+
+This however will create a new HLS version in ghcup, e.g. `1.7.0.0-105-gdc682ba1`, for both 8.10.7 and 9.2.4. If you want to switch back to the official bindists, run `ghcup set hls 1.7.0.0`.
+
 ### Cross support
 
 ghcup can compile and install a cross GHC for any target. However, this
@@ -241,24 +347,26 @@ You need to use the `--isolate` or `-i` flag followed by the directory path.
 
 Examples:
 
-1. install an isolated GHC version at location /home/user/isolated_dir/ghc/  
+1. install an isolated GHC version at location /home/user/isolated_dir/ghc/
     - `ghcup install ghc 8.10.5 --isolate /home/user/isolated_dir/ghc`
 
-2. isolated install Cabal at a location you desire  
+2. isolated install Cabal at a location you desire
     - `ghcup install cabal --isolate /home/username/my_isolated_dir/`
 
-3. do an isolated install with a custom bindist  
-    - `ghcup install ghc --isolate /home/username/my_isolated_dir/ -u 'https://gitlab.haskell.org/api/v4/projects/1/jobs/artifacts/master/raw/ghc-x86_64-fedora27-linux.tar.xz?job=validate-x86_64-linux-fedora27' head`
+3. do an isolated install with a custom bindist
+    - `ghcup install ghc --isolate /home/username/my_isolated_dir/ -u 'https://gitlab.haskell.org/ghc/ghc/-/jobs/artifacts/master/raw/ghc-x86_64-linux-fedora33-release.tar.xz?job=x86_64-linux-fedora33-release' head`
 
-4. isolated install HLS  
+4. isolated install HLS
     - `ghcup install hls --isolate /home/username/dir/hls/`
 
-5. you can even compile ghc to an isolated location.  
-    - `ghcup compile ghc -j 4 -v 9.0.1 -b 8.10.5 -i /home/username/my/dir/ghc` 
+5. you can even compile ghc to an isolated location.
+    - `ghcup compile ghc -j 4 -v 9.0.1 -b 8.10.5 -i /home/username/my/dir/ghc`
 
 ## Continuous integration
 
-On windows, ghcup can be installed automatically on a CI runner non-interactively like so:
+On Windows, GHCup can be installed automatically on a CI runner
+non-interactively, as below. The paramaters to the PowerShell script are
+specified positionally, after `-ArgumentList`:
 
 ```ps
 Set-ExecutionPolicy Bypass -Scope Process -Force;[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072;Invoke-Command -ScriptBlock ([ScriptBlock]::Create((Invoke-WebRequest https://www.haskell.org/ghcup/sh/bootstrap-haskell.ps1 -UseBasicParsing))) -ArgumentList $false,$true,$true,$false,$false,$false,$false,"C:\"
@@ -270,12 +378,10 @@ On linux/darwin/freebsd, run the following on your runner:
 curl --proto '=https' --tlsv1.2 -sSf https://get-ghcup.haskell.org | BOOTSTRAP_HASKELL_NONINTERACTIVE=1 BOOTSTRAP_HASKELL_MINIMAL=1 sh
 ```
 
-This will just install `ghcup` and on windows additionally `msys2`.
+This will just install `ghcup` and on Windows additionally MSYS2.
 
-For the full list of env variables and parameters to tweak the script behavior, see:
-
-* [bootstrap-haskell for linux/darwin/freebsd](https://gitlab.haskell.org/haskell/ghcup-hs/-/blob/master/scripts/bootstrap/bootstrap-haskell#L7)
-* [bootstrap-haskell.ps1 for windows](https://gitlab.haskell.org/haskell/ghcup-hs/-/blob/master/scripts/bootstrap/bootstrap-haskell.ps1#L17)
+See the installation scripts referred to above for the full list of environment
+variables and, in the case of Windows, parameters to tweak the script behavior.
 
 ### github workflows
 

docs/install.md

@@ -55,7 +55,9 @@ GHCup supports the following tools, which are also known as the **Haskell Toolch
 <table>
 <thead><tr><th>GHC Version</th><th>Tags</th></tr></thead>
 <tbody>
-<tr><td>9.2.3</td><td><span style="color:blue">latest</span>, base-4.16.2.0</td></tr>
+<tr><td>9.4.1</td><td><span style="color:blue">latest</span>, base-4.17.0.0</td></tr>
+<tr><td>9.2.4</td><td>base-4.16.3.0</td></tr>
+<tr><td>9.2.3</td><td>base-4.16.2.0</td></tr>
 <tr><td>9.2.2</td><td>base-4.16.1.0</td></tr>
 <tr><td>9.2.1</td><td>base-4.16.0.0</td></tr>
 <tr><td>9.0.2</td><td>base-4.15.1.0</td></tr>
@@ -208,6 +210,8 @@ The developers of the Haskell Language Server offer an [extension](https://githu
 3. Make sure your project uses the GHC version installed from GHCup (otherwise HLS is likely to fail on launch):
     - instructions for [stack](https://docs.haskellstack.org/en/stable/yaml_configuration/#system-ghc)
 
+On Linux, some users have reported an issue when VSCode is not launched from a terminal ("cannot find ghc version"). A solution is to [let HLS know about your GHCup on $PATH](https://github.com/haskell/vscode-haskell#stackcabalghc-can-not-be-found).
+
 ## Get help
 
 * [Libera IRC chat on #haskell-ghcup or #haskell](https://kiwiirc.com/nextclient/irc.libera.chat/?nick=Guest%7C?#haskell,#haskell-ghcup)

docs/steps.md

@@ -335,7 +335,7 @@ see the [Cabal user guide](https://cabal.readthedocs.io/en/stable/getting-starte
 
 To learn Haskell, try any of those:
 
-- A beginner friendly [4-lectures course](https://github.com/haskell-beginners-2022/course-plan) with exercises (by [Kowainik](https://kowainik.github.io/))
+- A beginner friendly [4-lectures course](https://github.com/haskell-beginners-2022/course-plan) with exercises (by [Dmitrii Kovanikov](https://kodimensional.dev/))
 - An in-depth university [CIS 194 Haskell course](https://www.cis.upenn.edu/~cis194/spring13/) including exercises (by [Brent Yorgey](https://byorgey.wordpress.com/))
 
 ## Projects to contribute to

ghcup.cabal

@@ -1,6 +1,6 @@
 cabal-version:      3.0
 name:               ghcup
-version:            0.1.18.0
+version:            0.1.18.1
 license:            LGPL-3.0-only
 license-file:       LICENSE
 copyright:          Julian Ospald 2020
@@ -21,6 +21,8 @@ extra-doc-files:
   README.md
 
 extra-source-files:
+  cbits/dirutils.c
+  cbits/dirutils.h
   data/build_mk/cross
   data/build_mk/default
   test/golden/GHCupInfo.json
@@ -69,6 +71,7 @@ library
     GHCup.Prelude.Process
     GHCup.Prelude.String.QQ
     GHCup.Prelude.Version.QQ
+    GHCup.Prompts
     GHCup.Requirements
     GHCup.Stack
     GHCup.Types
@@ -161,14 +164,13 @@ library
       , terminal-progress-bar  >=0.4.1
 
   if os(windows)
-    cpp-options:   -DIS_WINDOWS
+    cpp-options:     -DIS_WINDOWS
     other-modules:
       GHCup.Prelude.File.Windows
       GHCup.Prelude.Windows
-    -- GHCup.OptParse.Run uses this
-    exposed-modules:
-      GHCup.Prelude.Process.Windows
 
+    -- GHCup.OptParse.Run uses this
+    exposed-modules: GHCup.Prelude.Process.Windows
     build-depends:
       , bzlib
       , process  ^>=1.6.11.0
@@ -182,7 +184,10 @@ library
       GHCup.Prelude.Posix
       GHCup.Prelude.Process.Posix
 
-    c-sources:     cbits/dirutils.c
+    include-dirs:     cbits
+    includes:         dirutils.h
+    install-includes: dirutils.h
+    c-sources:        cbits/dirutils.c
     build-depends:
       , bz2              >=0.5.0.5 && <1.1
       , terminal-size    ^>=0.3.2.1
@@ -236,7 +241,7 @@ executable ghcup
     , aeson-pretty          ^>=0.8.8
     , async                 ^>=2.2.3
     , base                  >=4.12     && <5
-    , bytestring            >=0.10       && <0.12
+    , bytestring            >=0.10     && <0.12
     , cabal-plan            ^>=0.7.2
     , containers            ^>=0.6
     , deepseq               ^>=1.4
@@ -313,11 +318,11 @@ test-suite ghcup-test
 
   build-depends:
     , base                      >=4.12    && <5
-    , bytestring            >=0.10       && <0.12
+    , bytestring                >=0.10    && <0.12
     , containers                ^>=0.6
     , directory                 ^>=1.3.6.0
     , filepath                  ^>=1.4.2.1
-    , generic-arbitrary         >=0.1.0  && < 0.2.1 || >=0.2.2 && <0.3
+    , generic-arbitrary         >=0.1.0   && <0.2.1 || >=0.2.2 && <0.3
     , ghcup
     , hspec                     >=2.7.10  && <2.10
     , hspec-golden-aeson        ^>=0.9

lib/GHCup.hs

@@ -33,8 +33,8 @@ module GHCup (
 
 
 import           GHCup.Cabal
-import           GHCup.GHC
-import           GHCup.HLS
+import           GHCup.GHC             hiding ( GHCVer(..) )
+import           GHCup.HLS             hiding ( HLSVer(..) )
 import           GHCup.Stack
 import           GHCup.List
 import           GHCup.Download
@@ -206,9 +206,8 @@ rmGhcupDirs = do
       | isWindows = removeDirIfEmptyOrIsSymlink binDir
       | otherwise = do
           isXDGStyle <- liftIO useXDG
-          if not isXDGStyle
-            then removeDirIfEmptyOrIsSymlink binDir
-            else pure ()
+          when (not isXDGStyle) $
+            removeDirIfEmptyOrIsSymlink binDir
 
     reportRemainingFiles :: (MonadMask m, MonadIO m) => FilePath -> m [FilePath]
     reportRemainingFiles dir = do

lib/GHCup/Errors.hs

@@ -138,7 +138,7 @@ data AlreadyInstalled = AlreadyInstalled Tool Version
 instance Pretty AlreadyInstalled where
   pPrint (AlreadyInstalled tool ver') =
     (pPrint tool <> text "-" <> pPrint ver') <+> text "is already installed;"
-    <+> text "if you really want to reinstall it, you may want to run 'ghcup install cabal --force" <+> (pPrint ver' <> text "'")
+    <+> text "if you really want to reinstall it, you may want to run 'ghcup install" <+> pPrint tool <+> text "--force" <+> (pPrint ver' <> text "'")
 
 
 -- | The Directory is supposed to be empty, but wasn't.

lib/GHCup/GHC.hs

@@ -80,6 +80,12 @@ import qualified Data.Text.Encoding            as E
 import qualified Text.Megaparsec               as MP
 
 
+data GHCVer v = SourceDist v
+              | GitDist GitBranch
+              | RemoteDist URI
+
+
+
     ---------------------
     --[ Tool fetching ]--
     ---------------------
@@ -295,8 +301,9 @@ installUnpackedGHC path inst ver forceInstall addConfArgs
   | otherwise = do
       PlatformRequest {..} <- lift getPlatformReq
 
-      let alpineArgs
-           | ver >= [vver|8.2.2|], Linux Alpine <- _rPlatform
+      let ldOverride
+           | ver >= [vver|8.2.2|]
+           , _rPlatform `elem` [Linux Alpine, Darwin]
            = ["--disable-ld-override"]
            | otherwise
            = []
@@ -304,7 +311,7 @@ installUnpackedGHC path inst ver forceInstall addConfArgs
       lift $ logInfo "Installing GHC (this may take a while)"
       lEM $ execLogged "sh"
                        ("./configure" : ("--prefix=" <> fromInstallDir inst)
-                        : (alpineArgs <> (T.unpack <$> addConfArgs))
+                        : (ldOverride <> (T.unpack <$> addConfArgs))
                        )
                        (Just $ fromGHCupPath path)
                        "ghc-configure"
@@ -607,7 +614,7 @@ compileGHC :: ( MonadMask m
               , MonadUnliftIO m
               , MonadFail m
               )
-           => Either GHCTargetVersion GitBranch          -- ^ version to install
+           => GHCVer GHCTargetVersion
            -> Maybe Version            -- ^ overwrite version
            -> Either Version FilePath  -- ^ version to bootstrap with
            -> Maybe Int                -- ^ jobs
@@ -650,7 +657,7 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patches aargs buildFlavour hadr
 
     (workdir, tmpUnpack, tver) <- case targetGhc of
       -- unpack from version tarball
-      Left tver -> do
+      SourceDist tver -> do
         lift $ logDebug $ "Requested to compile: " <> tVerToText tver <> " with " <> either prettyVer T.pack bstrap
 
         -- download source tarball
@@ -671,8 +678,31 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patches aargs buildFlavour hadr
 
         pure (workdir, tmpUnpack, tver)
 
+      RemoteDist uri -> do
+        lift $ logDebug $ "Requested to compile (from uri): " <> T.pack (show uri)
+
+        -- download source tarball
+        tmpDownload <- lift withGHCupTmpDir
+        tmpUnpack <- lift mkGhcupTmpDir
+        tar <- liftE $ download uri Nothing Nothing (fromGHCupPath tmpDownload) Nothing False
+        (bf, tver) <- liftE $ cleanUpOnError @'[UnknownArchive, ArchiveResult, ProcessError] tmpUnpack $ do
+          liftE $ unpackToDir (fromGHCupPath tmpUnpack) tar
+          let regex = [s|^(.*/)*boot$|] :: B.ByteString
+          [bootFile] <- liftIO $ findFilesDeep
+            tmpUnpack
+            (makeRegexOpts compExtended
+                           execBlank
+                           regex
+            )
+          tver <- liftE $ getGHCVer (appendGHCupPath tmpUnpack (takeDirectory bootFile))
+          pure (bootFile, tver)
+
+        let workdir = appendGHCupPath tmpUnpack (takeDirectory bf)
+
+        pure (workdir, tmpUnpack, mkTVer tver)
+
       -- clone from git
-      Right GitBranch{..} -> do
+      GitDist GitBranch{..} -> do
         tmpUnpack <- lift mkGhcupTmpDir
         let git args = execLogged "git" ("--no-pager":args) (Just $ fromGHCupPath tmpUnpack) "git" Nothing
         tver <- reThrowAll @_ @'[PatchFailed, ProcessError, NotFoundInPATH, DigestError, DownloadFailed, GPGError] DownloadFailed $ do
@@ -715,14 +745,7 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patches aargs buildFlavour hadr
           liftE $ applyAnyPatch patches (fromGHCupPath tmpUnpack)
 
           -- bootstrap
-          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)
-          tver <- case _exitCode of
-            ExitSuccess -> throwEither . MP.parse ghcProjectVersion "" . T.pack . stripNewlineEnd . T.unpack . decUTF8Safe' $ _stdOut
-            ExitFailure c -> fail ("Could not figure out GHC project version. Exit code was: " <> show c <> ". Error was: " <> T.unpack (decUTF8Safe' _stdErr))
-
+          tver <- liftE $ 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 <>
@@ -795,11 +818,29 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patches aargs buildFlavour hadr
     pure installVer
 
  where
+  getGHCVer :: ( MonadReader env m
+               , HasSettings env
+               , HasDirs env
+               , HasLog env
+               , MonadIO m
+               , MonadThrow m
+               )
+            => GHCupPath
+            -> Excepts '[ProcessError] 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
+      ExitFailure c -> throwE $ NonZeroExit c "make" ["show!", "--quiet", "VALUE=ProjectVersion" ]
+
   defaultConf =
     let cross_mk = $(LitE . StringL <$> (qAddDependentFile "data/build_mk/cross" >> runIO (readFile "data/build_mk/cross")))
         default_mk = $(LitE . StringL <$> (qAddDependentFile "data/build_mk/default" >> runIO (readFile "data/build_mk/default")))
     in case targetGhc of
-         Left (GHCTargetVersion (Just _) _) -> cross_mk
+         SourceDist (GHCTargetVersion (Just _) _) -> cross_mk
          _ -> default_mk
 
   compileHadrianBindist :: ( MonadReader env m
@@ -976,7 +1017,7 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patches aargs buildFlavour hadr
 
    -- for cross, we need Stage1Only
     case targetGhc of
-      Left (GHCTargetVersion (Just _) _) -> when ("Stage1Only = YES" `notElem` lines') $ throwE
+      SourceDist (GHCTargetVersion (Just _) _) -> when ("Stage1Only = YES" `notElem` lines') $ throwE
         (InvalidBuildConfig
           [s|Cross compiling needs to be a Stage1 build, add "Stage1Only = YES" to your config!|]
         )

lib/GHCup/HLS.hs

@@ -71,6 +71,12 @@ import qualified Text.Megaparsec               as MP
 import Text.PrettyPrint.HughesPJClass (prettyShow)
 
 
+data HLSVer = SourceDist Version
+            | GitDist GitBranch
+            | HackageDist Version
+            | RemoteDist URI
+
+
 
     --------------------
     --[ Installation ]--
@@ -324,13 +330,14 @@ compileHLS :: ( MonadMask m
               , MonadUnliftIO m
               , MonadFail m
               )
-           => Either Version GitBranch
+           => HLSVer
            -> [Version]
            -> Maybe Int
            -> Either Bool Version
            -> InstallDir
            -> Maybe (Either FilePath URI)
            -> Maybe URI
+           -> Bool
            -> Maybe (Either FilePath [URI])  -- ^ patches
            -> [Text]                   -- ^ additional args to cabal install
            -> Excepts '[ NoDownload
@@ -343,15 +350,18 @@ compileHLS :: ( MonadMask m
                        , BuildFailed
                        , NotInstalled
                        ] m Version
-compileHLS targetHLS ghcs jobs ov installDir cabalProject cabalProjectLocal patches cabalArgs = do
+compileHLS targetHLS ghcs jobs ov installDir cabalProject cabalProjectLocal updateCabal patches cabalArgs = do
   PlatformRequest { .. } <- lift getPlatformReq
   GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
   Dirs { .. } <- lift getDirs
 
+  when updateCabal $ reThrowAll @_ @'[ProcessError] DownloadFailed $ do
+    lift $ logInfo "Updating cabal DB"
+    lEM $ exec "cabal" ["update"] (Just $ fromGHCupPath tmpDir) Nothing
 
-  (workdir, tver, git_describe) <- case targetHLS of
+  (workdir, tmpUnpack, tver, git_describe) <- case targetHLS of
     -- unpack from version tarball
-    Left tver -> do
+    SourceDist tver -> do
       lift $ logDebug $ "Requested to compile: " <> prettyVer tver
 
       -- download source tarball
@@ -369,10 +379,47 @@ compileHLS targetHLS ghcs jobs ov installDir cabalProject cabalProjectLocal patc
                        (liftE . intoSubdir tmpUnpack)
                        (view dlSubdir dlInfo)
 
-      pure (workdir, tver, Nothing)
+      pure (workdir, tmpUnpack, tver, Nothing)
+
+    HackageDist tver -> do
+      lift $ logDebug $ "Requested to compile (from hackage): " <> prettyVer tver
+
+      -- download source tarball
+      tmpUnpack <- lift mkGhcupTmpDir
+      let hls = "haskell-language-server-" <> T.unpack (prettyVer tver)
+      reThrowAll @_ @'[ProcessError] DownloadFailed $ do
+        -- unpack
+        lEM $ exec "cabal" ["unpack", hls] (Just $ fromGHCupPath tmpUnpack) Nothing
+
+      let workdir = appendGHCupPath tmpUnpack hls
+
+      pure (workdir, tmpUnpack, tver, Nothing)
+
+    RemoteDist uri -> do
+      lift $ logDebug $ "Requested to compile (from uri): " <> T.pack (show uri)
+
+      -- download source tarball
+      tmpDownload <- lift withGHCupTmpDir
+      tmpUnpack <- lift mkGhcupTmpDir
+      tar <- liftE $ download uri Nothing Nothing (fromGHCupPath tmpDownload) Nothing False
+      (cf, tver) <- liftE $ cleanUpOnError tmpUnpack $ do
+        unpackToDir (fromGHCupPath tmpUnpack) tar
+        let regex = [s|^(.*/)*haskell-language-server\.cabal$|] :: B.ByteString
+        [cabalFile] <- liftIO $ findFilesDeep
+          tmpUnpack
+          (makeRegexOpts compExtended
+                         execBlank
+                         regex
+          )
+        tver <- getCabalVersion (fromGHCupPath tmpUnpack </> cabalFile)
+        pure (cabalFile, tver)
+
+      let workdir = appendGHCupPath tmpUnpack (takeDirectory cf)
+
+      pure (workdir, tmpUnpack, tver, Nothing)
 
     -- clone from git
-    Right GitBranch{..} -> do
+    GitDist GitBranch{..} -> do
       tmpUnpack <- lift mkGhcupTmpDir
       let git args = execLogged "git" ("--no-pager":args) (Just $ fromGHCupPath tmpUnpack) "git" Nothing
       reThrowAll @_ @'[ProcessError] DownloadFailed $ do
@@ -409,15 +456,7 @@ compileHLS targetHLS ghcs jobs ov installDir cabalProject cabalProjectLocal patc
                         then pure Nothing
                         else fmap Just $ gitOut ["describe", "--tags"] (fromGHCupPath tmpUnpack)
         chash <- gitOut ["rev-parse", "HEAD" ] (fromGHCupPath tmpUnpack)
-        (Just gpd) <- parseGenericPackageDescriptionMaybe
-          <$> liftIO (B.readFile (fromGHCupPath tmpUnpack </> "haskell-language-server.cabal"))
-        let tver = (\c -> Version Nothing c [] Nothing)
-                 . NE.fromList . fmap (NE.fromList . (:[]) . digits . fromIntegral)
-                 . versionNumbers
-                 . pkgVersion
-                 . package
-                 . packageDescription
-                 $ gpd
+        tver <- getCabalVersion (fromGHCupPath tmpUnpack </> "haskell-language-server.cabal")
 
         liftE $ catchWarn $ lEM @_ @'[ProcessError] $ darwinNotarization _rPlatform (fromGHCupPath tmpUnpack)
         lift $ logInfo $ "Examining git ref " <> T.pack ref <> "\n  " <>
@@ -425,7 +464,7 @@ compileHLS targetHLS ghcs jobs ov installDir cabalProject cabalProjectLocal patc
                                     (if not shallow_clone then "\n  " <> "'git describe' output: " <> fromJust git_describe else mempty) <>
                                     (if isCommitHash ref then mempty else "\n  " <> "commit hash: " <> chash)
 
-        pure (tmpUnpack, tver, git_describe)
+        pure (tmpUnpack, tmpUnpack, tver, git_describe)
 
   -- the version that's installed may differ from the
   -- compiled version, so the user can overwrite it
@@ -441,7 +480,7 @@ compileHLS targetHLS ghcs jobs ov installDir cabalProject cabalProjectLocal patc
                   Right v -> pure v
 
   liftE $ runBuildAction
-    workdir
+    tmpUnpack
     (reThrowAll @_ @'[GPGError, DownloadFailed, DigestError, PatchFailed, ProcessError, FileAlreadyExistsError, CopyError] @'[BuildFailed] (BuildFailed $ fromGHCupPath workdir) $ do
       let tmpInstallDir = fromGHCupPath workdir </> "out"
       liftIO $ createDirRecursive' tmpInstallDir
@@ -457,14 +496,22 @@ compileHLS targetHLS ghcs jobs ov installDir cabalProject cabalProjectLocal patc
               pure "cabal.project"
           | otherwise -> pure (takeFileName cp)
         Just (Right uri) -> do
-          tmpUnpack <- lift withGHCupTmpDir
-          cp <- liftE $ download uri Nothing Nothing (fromGHCupPath tmpUnpack) (Just "cabal.project") False
+          tmpUnpack' <- lift withGHCupTmpDir
+          cp <- liftE $ download uri Nothing Nothing (fromGHCupPath tmpUnpack') (Just "cabal.project") False
           copyFileE cp (fromGHCupPath workdir </> "cabal.project") False
           pure "cabal.project"
-        Nothing -> pure "cabal.project"
+        Nothing
+          | HackageDist _ <- targetHLS -> do
+              liftIO $ B.writeFile (fromGHCupPath workdir </> "cabal.project") "packages: ./"
+              pure "cabal.project"
+          | RemoteDist _ <- targetHLS -> do
+              let cabalFile = fromGHCupPath workdir </> "cabal.project"
+              liftIO $ whenM (not <$> doesFileExist cabalFile) $ B.writeFile cabalFile "packages: ./"
+              pure "cabal.project"
+          | otherwise -> pure "cabal.project"
       forM_ cabalProjectLocal $ \uri -> do
-        tmpUnpack <- lift withGHCupTmpDir
-        cpl <- liftE $ download uri Nothing Nothing (fromGHCupPath tmpUnpack) (Just (cp <.> "local")) False
+        tmpUnpack' <- lift withGHCupTmpDir
+        cpl <- liftE $ download uri Nothing Nothing (fromGHCupPath tmpUnpack') (Just (cp <.> "local")) False
         copyFileE cpl (fromGHCupPath workdir </> cp <.> "local") False
       artifacts <- forM (sort ghcs) $ \ghc -> do
         let ghcInstallDir = tmpInstallDir </> T.unpack (prettyVer ghc)
@@ -658,3 +705,19 @@ rmHLSVer ver = do
     case headMay . reverse . sort $ hlsVers of
       Just latestver -> liftE $ setHLS latestver SetHLSOnly Nothing
       Nothing        -> pure ()
+
+
+getCabalVersion :: (MonadIO m, MonadFail m) => FilePath -> m Version
+getCabalVersion fp = do
+  contents <- liftIO $ B.readFile fp
+  gpd <- case parseGenericPackageDescriptionMaybe contents of
+           Nothing -> fail $ "could not parse cabal file: " <> fp
+           Just r -> pure r
+  let tver = (\c -> Version Nothing c [] Nothing)
+           . NE.fromList . fmap (NE.fromList . (:[]) . digits . fromIntegral)
+           . versionNumbers
+           . pkgVersion
+           . package
+           . packageDescription
+           $ gpd
+  pure tver

lib/GHCup/Prompts.hs

@@ -0,0 +1,28 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE FlexibleContexts #-}
+
+module GHCup.Prompts
+  ( PromptQuestion,
+    PromptResponse (..),
+    getUserPromptResponse,
+  )
+where
+
+import Control.Monad.Reader
+import qualified Data.Text.IO as TIO
+import GHCup.Prelude.Logger
+import GHCup.Types.Optics
+import GHCup.Types (PromptQuestion, PromptResponse(..))
+
+getUserPromptResponse :: ( HasLog env
+                         , MonadReader env m
+                         , MonadIO m)
+                      => PromptQuestion
+                      -> m PromptResponse
+
+getUserPromptResponse prompt = do
+  logInfo prompt
+  resp <- liftIO TIO.getLine
+  if resp `elem` ["YES", "yes", "y", "Y"]
+    then pure PromptYes
+    else pure PromptNo

lib/GHCup/Types.hs

@@ -657,10 +657,7 @@ isSafeDir (IsolateDirResolved _) = False
 isSafeDir (GHCupDir _)           = True
 isSafeDir (GHCupBinDir _)        = False
 
+type PromptQuestion = Text
 
-
-
-
-
-
-
+data PromptResponse = PromptYes | PromptNo
+  deriving (Show, Eq)

lib/GHCup/Utils.hs

@@ -1097,7 +1097,8 @@ runBuildAction bdir action = do
 
 -- | Clean up the given directory if the action fails,
 -- depending on the Settings.
-cleanUpOnError :: ( MonadReader env m
+cleanUpOnError :: forall e m a env .
+                  ( MonadReader env m
                   , HasDirs env
                   , HasSettings env
                   , MonadIO m

scripts/bootstrap/bootstrap-haskell

@@ -12,7 +12,8 @@
 #   * BOOTSTRAP_HASKELL_VERBOSE - any nonzero value for more verbose installation
 #   * BOOTSTRAP_HASKELL_GHC_VERSION - the ghc version to install
 #   * BOOTSTRAP_HASKELL_CABAL_VERSION - the cabal version to install
-#   * BOOTSTRAP_HASKELL_INSTALL_STACK - whether to install latest stack
+#   * BOOTSTRAP_HASKELL_INSTALL_NO_STACK - disable installation of stack
+#   * BOOTSTRAP_HASKELL_INSTALL_NO_STACK_HOOK - disable installation stack ghcup hook
 #   * BOOTSTRAP_HASKELL_INSTALL_HLS - whether to install latest hls
 #   * BOOTSTRAP_HASKELL_ADJUST_BASHRC - whether to adjust PATH in bashrc (prepend)
 #   * BOOTSTRAP_HASKELL_ADJUST_CABAL_CONFIG - whether to adjust mingw paths in cabal.config on windows
@@ -27,7 +28,7 @@
 
 plat="$(uname -s)"
 arch=$(uname -m)
-ghver="0.1.17.8"
+ghver="0.1.18.0"
 : "${GHCUP_BASE_URL:=https://downloads.haskell.org/~ghcup}"
 
 export GHCUP_SKIP_UPDATE_CHECK=yes
@@ -140,8 +141,12 @@ ecabal() {
 }
 
 _ecabal() {
-    # shellcheck disable=SC2086
-    "${GHCUP_BIN}/cabal" "$@"
+    if [ -n "${CABAL_BIN}" ] ; then
+        "${CABAL_BIN}" "$@"
+    else
+        # shellcheck disable=SC2086
+        "${GHCUP_BIN}/cabal" "$@"
+    fi
 }
 
 _done() {
@@ -655,7 +660,7 @@ ask_hls() {
 		warn "Do you want to install haskell-language-server (HLS)?"
 		warn "HLS is a language-server that provides IDE-like functionality"
 		warn "and can integrate with different editors, such as Vim, Emacs, VS Code, Atom, ..."
-		warn "Also see https://github.com/haskell/haskell-language-server/blob/master/README.md"
+		warn "Also see https://haskell-language-server.readthedocs.io/en/stable/"
 		warn ""
 		warn "[Y] Yes  [N] No  [?] Help (default is \"N\")."
 		warn ""
@@ -688,40 +693,44 @@ ask_hls() {
 }
 
 ask_stack() {
-	if [ -n "${BOOTSTRAP_HASKELL_INSTALL_STACK}" ] ; then
+    if [ -n "${BOOTSTRAP_HASKELL_INSTALL_NO_STACK}" ] ; then
+		return 0
+    elif [ -n "${BOOTSTRAP_HASKELL_INSTALL_NO_STACK_HOOK}" ] ; then
 		return 1
 	fi
 
 	if [ -z "${BOOTSTRAP_HASKELL_NONINTERACTIVE}" ] ; then
 		echo "-------------------------------------------------------------------------------"
 
-		warn "Do you want to install stack?"
-		warn "Stack is a haskell build tool similar to cabal that is used by some projects."
-		warn "Also see https://docs.haskellstack.org/"
+		warn "Do you want to enable better integration of stack with GHCup?"
+        warn "This means that stack won't install its own GHC versions, but uses GHCup's."
+        warn "For more information see:"
+        warn "  https://docs.haskellstack.org/en/stable/yaml_configuration/#ghc-installation-customisation-experimental"
+        warn "If you want to keep stacks vanilla behavior, answer 'No'."
 		warn ""
-		warn "[Y] Yes  [N] No  [?] Help (default is \"N\")."
+		warn "[Y] Yes  [N] No  [?] Help (default is \"Y\")."
 		warn ""
 
 		while true; do
 			read -r stack_answer </dev/tty
 
 			case $stack_answer in
-				[Yy]*)
+				[Yy]* | "")
+					return 2 ;;
+				[Nn]*)
 					return 1 ;;
-				[Nn]* | "")
-					return 0 ;;
 				*)
 					echo "Possible choices are:"
 					echo
-					echo "Y - Yes, install stack"
-					echo "N - No, don't install anything more (default)"
+                    echo "Y - Yes, enable better integration (default)"
+					echo "N - No, keep stacks vanilla behavior"
 					echo
 					echo "Please make your choice and press ENTER."
 					;;
 			esac
 		done
 	else
-		return 0
+		return 2
 	fi
 
 	unset stack_answer
@@ -738,7 +747,7 @@ echo "This script can download and install the following binaries:"
 echo "  * ghcup - The Haskell toolchain installer"
 echo "  * ghc   - The Glasgow Haskell Compiler"
 echo "  * cabal - The Cabal build tool for managing Haskell software"
-echo "  * stack - (optional) A cross-platform program for developing Haskell projects"
+echo "  * stack - A cross-platform program for developing Haskell projects (similar to cabal)"
 echo "  * hls   - (optional) A language server for developers to integrate with their editor/IDE"
 echo
 if [ -z "${GHCUP_USE_XDG_DIRS}" ] ; then
@@ -817,7 +826,7 @@ else # don't install ghc and cabal
 				# we'll remove it afterwards
 				tmp_dir="$(mktemp -d)"
 				eghcup --cache install cabal -i "${tmp_dir}" "${BOOTSTRAP_HASKELL_CABAL_VERSION}"
-				PATH="${tmp_dir}:$PATH" do_cabal_config_init $ask_cabal_config_init_answer
+				CABAL_BIN="${tmp_dir}/cabal" do_cabal_config_init $ask_cabal_config_init_answer
 				rm "${tmp_dir}/cabal"
 				unset tmp_dir
 				;;
@@ -835,7 +844,35 @@ esac
 
 case $ask_stack_answer in
 	1)
-		_eghcup --cache install stack || warn "Stack installation failed, continuing anyway"
+		_eghcup --cache install stack || die "Stack installation failed"
+		;;
+	2)
+		_eghcup --cache install stack || die "Stack installation failed"
+        edo mkdir -p "${STACK_ROOOT:-$HOME/.stack}"/hooks
+        hook_exe="${STACK_ROOOT:-$HOME/.stack}"/hooks/ghc-install.sh
+        hook_url="https://www.haskell.org/ghcup/sh/hooks/stack/ghc-install.sh"
+
+        if [ -e "${hook_exe}" ] ; then
+            warn "$hook_exe already exists, skipping hook installation."
+            warn "If you want to reinstall the hook, delete it manually and re-run"
+            warn "this script!"
+        else
+            case "${BOOTSTRAP_HASKELL_DOWNLOADER}" in
+                "curl")
+                    # shellcheck disable=SC2086
+                    edo curl -Lf ${GHCUP_CURL_OPTS} "${hook_url}" > "${hook_exe}"
+                    ;;
+                "wget")
+                    # shellcheck disable=SC2086
+                    edo wget -O /dev/stdout ${GHCUP_WGET_OPTS} "${hook_url}" > "${hook_exe}"
+                    ;;
+                *)
+                    die "Unknown downloader: ${BOOTSTRAP_HASKELL_DOWNLOADER}"
+                    ;;
+            esac
+            edo chmod +x "${hook_exe}"
+        fi
+
 		;;
 	*) ;;
 esac

scripts/bootstrap/bootstrap-haskell.ps1

@@ -577,8 +577,8 @@ $Msys2Shell = ('{0}\msys2_shell.cmd' -f $MsysDir)
 # The bootstrap script is always silent, since we ask relevant questions here
 $SilentExport = 'export BOOTSTRAP_HASKELL_NONINTERACTIVE=1 ;'
 
-if ($InstallStack) {
-  $StackInstallExport = 'export BOOTSTRAP_HASKELL_INSTALL_STACK=1 ;'
+if (!($InstallStack)) {
+  $StackInstallExport = 'export BOOTSTRAP_HASKELL_INSTALL_NO_STACK=1 ;'
 }
 
 if ($InstallHLS) {

scripts/hooks/stack/ghc-install.sh

@@ -0,0 +1,24 @@
+#!/bin/sh
+
+# !! KEEP THIS SCRIPT POSIX COMPLIANT !!
+
+# see https://docs.haskellstack.org/en/stable/yaml_configuration/#ghc-installation-customisation-experimental
+# for documentation about hooks
+
+set -eu
+
+case $HOOK_GHC_TYPE in
+    bindist)
+        ghcdir=$(ghcup whereis --directory ghc "$HOOK_GHC_VERSION" || ghcup run --ghc "$HOOK_GHC_VERSION" --install) || exit 3
+        printf "%s/ghc" "${ghcdir}"
+        ;;
+    git)
+        # TODO: should be somewhat possible
+        >&2 echo "Hook doesn't support installing from source"
+        exit 1
+        ;;
+    *)
+        >&2 echo "Unsupported GHC installation type: $HOOK_GHC_TYPE"
+        exit 2
+        ;;
+esac