Implement ghcup unset

Fixes after formatting changes.

.gitlab/ghcup_env

@@ -1,9 +1,11 @@
 if [ "${OS}" = "WINDOWS" ] ; then
 	export GHCUP_INSTALL_BASE_PREFIX="$CI_PROJECT_DIR"
-	export PATH="$GHCUP_INSTALL_BASE_PREFIX/ghcup/bin:$CI_PROJECT_DIR/.local/bin:$PATH"
+	export GHCUP_BIN="$CI_PROJECT_DIR/ghcup/bin"
+	export PATH="$GHCUP_BIN:$CI_PROJECT_DIR/.local/bin:$PATH"
 	export TMPDIR="$CI_PROJECT_DIR/tmp"
 else
 	export GHCUP_INSTALL_BASE_PREFIX="$CI_PROJECT_DIR"
-	export PATH="$CI_PROJECT_DIR/.ghcup/bin:$CI_PROJECT_DIR/.local/bin:/opt/llvm/bin:$PATH"
+	export GHCUP_BIN="$CI_PROJECT_DIR/.ghcup/bin"
+	export PATH="$GHCUP_BIN:$CI_PROJECT_DIR/.local/bin:/opt/llvm/bin:$PATH"
 	export TMPDIR="$CI_PROJECT_DIR/tmp"
 fi

.gitlab/script/ghcup_version.sh

@@ -101,6 +101,10 @@ eghcup install ghc ${GHC_VERSION}
 eghcup set ghc ${GHC_VERSION}
 eghcup install cabal ${CABAL_VERSION}
 [ `$(eghcup whereis cabal ${CABAL_VERSION}) --numeric-version` = "${CABAL_VERSION}" ]
+eghcup unset cabal
+"$GHCUP_BIN"/cabal --version && exit || echo yes
+eghcup set cabal ${CABAL_VERSION}
+[ `$(eghcup whereis cabal ${CABAL_VERSION}) --numeric-version` = "${CABAL_VERSION}" ]
 
 cabal --version
 
@@ -151,9 +155,13 @@ else
 	[ "$(ghc --numeric-version)" = "8.10.3" ]
 	eghcup set ${GHC_VERSION}
 	[ "$(ghc --numeric-version)" = "${ghc_ver}" ]
+	eghcup unset ghc
+    "$GHCUP_BIN"/ghc --numeric-version && exit || echo yes
+	eghcup set ${GHC_VERSION}
 	eghcup --offline rm 8.10.3
 	[ "$(ghc --numeric-version)" = "${ghc_ver}" ]
 
+
 	if [ "${OS}" = "DARWIN" ] ; then
 		eghcup install hls
 		$(eghcup whereis hls) --version
@@ -164,9 +172,13 @@ else
 		if [ "${ARCH}" = "64" ] ; then
 			eghcup install hls
 			haskell-language-server-wrapper --version
+			eghcup unset hls
+			"$GHCUP_BIN"/haskell-language-server-wrapper --version && exit || echo yes
 
 			eghcup install stack
 			stack --version
+			eghcup unset hls
+			"$GHCUP_BIN"/stack --version && exit || echo yes
 		fi
 	fi
 fi

README.md

@@ -13,11 +13,12 @@ Similar in scope to [rustup](https://github.com/rust-lang-nursery/rustup.rs), [p
 <a href="https://opencollective.com/ghcup#category-CONTRIBUTE"><img src="https://opencollective.com/webpack/donate/button@2x.png?color=blue" alt="Donate" width="150"></a>
 
    * [Installation](#installation)
-     * [Simple bootstrap](#simple-bootstrap)
+     * [Supported platforms](#supported-platforms)
      * [Manual install](#manual-install)
      * [Vim integration](#vim-integration)
    * [Usage](#usage)
      * [Configuration](#configuration)
+     * [GPG verification](#gpg-verification)
      * [Manpages](#manpages)
      * [Shell-completion](#shell-completion)
      * [Compiling GHC from source](#compiling-ghc-from-source)
@@ -35,9 +36,59 @@ Similar in scope to [rustup](https://github.com/rust-lang-nursery/rustup.rs), [p
 
 ## Installation
 
-### Simple bootstrap
+Most users should follow the instructions at [https://www.haskell.org/ghcup/](https://www.haskell.org/ghcup/).
+Advanced users may want to perform a [manual installation](#manual-install).
 
-Follow the instructions at [https://www.haskell.org/ghcup/](https://www.haskell.org/ghcup/)
+### Supported platforms
+
+This list may not be exhaustive and specifies support for bindists only.
+
+| Platform | Architecture | ghcup | GHC | cabal | HLS | stack | 
+| ------ | ------ | ------ | ------ | ------ | ------ | ------ |
+| Windows 7 | amd64 | ❔ | ✅ | ✅ | ✅ | ✅ |
+| Windows 10 | amd64 | ✅ | ✅ | ✅ | ✅ | ✅ |
+| Windows Server 2016 | amd64 | ✅ | ✅ | ✅ | ✅ | ✅ |
+| Windows Server 2019 | amd64 | ✅ | ✅ | ✅ | ✅ | ✅ |
+| Windows Server 2022 | amd64 | ✅ | ✅ | ✅ | ✅ | ✅ |
+| Windows WSL1 | amd64 | ❌ | ❔ | ❔ | ❔ | ❔ |
+| Windows WSL2 | amd64 | ✅ | ✅ | ✅ | ✅ | ✅ |
+| MacOS >=13 | amd64 | ✅ | ✅ | ✅ | ✅ | ✅ |
+| MacOS <13 | amd64 | ❌ | ❔ | ❔ | ❔ | ❔ |
+| MacOS | aarch64 | ✅ | ✅ | ✅ | ⚠️ | ❌ |
+| FreeBSD | amd64 | ✅ | ⚠️ | ✅ | ⚠️ | ❌ |
+| Linux generic | x86 | ✅ | ✅ | ✅ | ✅ | ✅ |
+| Linux generic | amd64 | ✅ | ✅ | ✅ | ✅ | ✅ |
+| Linux generic | aarch64 | ✅ | ⚠️ | ✅ | ⚠️ | ❌ |
+| Linux generic | armv7 | ✅ | ⚠️ | ✅ | ⚠️ | ❌ |
+
+#### Windows 7
+
+May or may not work, several issues:
+
+* https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/140
+* https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/197
+
+#### WSL1
+
+Unsupported. GHC may or may not work. Upgrade to WSL2.
+
+#### MacOS <13
+
+Not supported. Would require separate binaries, since >=13 binaries are incompatible.
+Please upgrade.
+
+#### MacOS aarch64
+
+HLS bindists are still experimental. Stack is theoretically supported, but has no binaries yet.
+
+#### FreeBSD
+
+Lacks some upstream bindists and may need compat libs, since most bindists are built on FreeBSD-12.
+HLS bindists are experimental.
+
+#### Linux ARMv7/AARCH64
+
+Lower availability of bindists. HLS only has experimental ones. Stack not supported currently.
 
 ### Manual install
 
@@ -96,6 +147,34 @@ explaining all possible configurations can be found in this repo: [config.yaml](
 
 Partial configuration is fine. Command line options always override the config file settings.
 
+### GPG verification
+
+GHCup supports verifying the GPG signature of the metadata file. The metadata file then contains SHA256 hashes of all downloads, so
+this is cryptographically secure.
+
+First, obtain the gpg key:
+
+```sh
+gpg --batch --keyserver keys.openpgp.org --recv-keys 7784930957807690A66EBDBE3786C5262ECB4A3F
+```
+
+Then verify the gpg key in one of these ways:
+
+1. find out where I live and visit me to do offline key signing
+2. figure out my mobile phone number and call me to verify the fingerprint
+3. more boring: contact me on Libera IRC (`maerwald`) and verify the fingerprint
+
+Once you've verified the key, you have to figure out if you trust me.
+
+If you trust me, then you can configure gpg in `~/.ghcup/config.yaml`:
+
+```yml
+gpg-setting: GPGLax # GPGStrict | GPGLax | GPGNone
+```
+
+In `GPGStrict` mode, ghcup will fail if verification fails. In `GPGLax` mode it will just print a warning.
+You can also pass the mode via `ghcup --gpg <strict|lax|none>`.
+
 ### Manpages
 
 For man pages to work you need [man-db](http://man-db.nongnu.org/) as your `man` provider, then issue `man ghc`. Manpages only work for the currently set ghc.
@@ -156,6 +235,7 @@ This is the complete list of env variables that change GHCup behavior:
 * `GHCUP_INSTALL_BASE_PREFIX`: the base of ghcup (default: `$HOME`)
 * `GHCUP_CURL_OPTS`: additional options that can be passed to curl
 * `GHCUP_WGET_OPTS`: additional options that can be passed to wget
+* `GHCUP_GPG_OPTS`: additional options that can be passed to gpg
 * `GHCUP_SKIP_UPDATE_CHECK`: Skip the (possibly annoying) update check when you run a command
 * `CC`/`LD` etc.: full environment is passed to the build system when compiling GHC via GHCup
 

app/ghcup-gen/Main.hs

@@ -119,7 +119,7 @@ main = do
                                   , rawOutter    = \_ -> pure ()
                                   }
   dirs <- liftIO getAllDirs
-  let leanAppstate = LeanAppState (Settings True False Never Curl True GHCupURL False) dirs defaultKeyBindings loggerConfig
+  let leanAppstate = LeanAppState (Settings True False Never Curl True GHCupURL False GPGNone) dirs defaultKeyBindings loggerConfig
 
   pfreq <- (
     flip runReaderT leanAppstate . runE @'[NoCompatiblePlatform, NoCompatibleArch, DistroNotFound] $ platformRequest
@@ -129,7 +129,7 @@ main = do
               flip runReaderT leanAppstate $ logError $ T.pack $ prettyShow e
               liftIO $ exitWith (ExitFailure 2)
 
-  let appstate = AppState (Settings True False Never Curl True GHCupURL False) dirs defaultKeyBindings (GHCupInfo mempty mempty mempty) pfreq loggerConfig
+  let appstate = AppState (Settings True False Never Curl True GHCupURL False GPGNone) dirs defaultKeyBindings (GHCupInfo mempty mempty mempty) pfreq loggerConfig
 
   _ <- customExecParser (prefs showHelpOnError) (info (opts <**> helper) idm)
     >>= \Options {..} -> case optCommand of

app/ghcup-gen/Validate.hs

@@ -229,6 +229,7 @@ validateTarballs (TarballFilter etool versionRegex) dls gt = do
   downloadAll ref dli = do
     r <- runResourceT
       . runE @'[DigestError
+               , GPGError
                , DownloadFailed
                , UnknownArchive
                , ArchiveResult
@@ -237,7 +238,7 @@ validateTarballs (TarballFilter etool versionRegex) dls gt = do
         case etool of
           Right (Just GHCup) -> do
             tmpUnpack <- lift mkGhcupTmpDir
-            _ <- liftE $ download (_dlUri dli) (Just (_dlHash dli)) tmpUnpack Nothing False
+            _ <- liftE $ download (_dlUri dli) Nothing (Just (_dlHash dli)) tmpUnpack Nothing False
             pure Nothing
           Right _ -> do
             p <- liftE $ downloadCached dli Nothing
@@ -247,7 +248,7 @@ validateTarballs (TarballFilter etool versionRegex) dls gt = do
               $ p
           Left ShimGen -> do
             tmpUnpack <- lift mkGhcupTmpDir
-            _ <- liftE $ download (_dlUri dli) (Just (_dlHash dli)) tmpUnpack Nothing False
+            _ <- liftE $ download (_dlUri dli) Nothing (Just (_dlHash dli)) tmpUnpack Nothing False
             pure Nothing
     case r of
       VRight (Just basePath) -> do

app/ghcup/BrickMain.hs

@@ -429,6 +429,7 @@ install' _ (_, ListResult {..}) = do
               , BuildFailed
               , TagNotFound
               , DigestError
+              , GPGError
               , DownloadFailed
               , DirNotEmpty
               , NoUpdate
@@ -440,19 +441,19 @@ install' _ (_, ListResult {..}) = do
       case lTool of
         GHC   -> do
           let vi = getVersionInfo lVer GHC dls
-          liftE $ installGHCBin lVer Nothing $> vi
+          liftE $ installGHCBin lVer Nothing False $> vi
         Cabal -> do
           let vi = getVersionInfo lVer Cabal dls
-          liftE $ installCabalBin lVer Nothing $> vi
+          liftE $ installCabalBin lVer Nothing False $> vi
         GHCup -> do
           let vi = snd <$> getLatest dls GHCup
           liftE $ upgradeGHCup Nothing False $> vi
         HLS   -> do
           let vi = getVersionInfo lVer HLS dls
-          liftE $ installHLSBin lVer Nothing $> vi
+          liftE $ installHLSBin lVer Nothing False $> vi
         Stack -> do
           let vi = getVersionInfo lVer Stack dls
-          liftE $ installStackBin lVer Nothing $> vi
+          liftE $ installStackBin lVer Nothing False $> vi
     )
     >>= \case
           VRight vi                         -> do
@@ -547,6 +548,7 @@ settings' = unsafePerformIO $ do
                                 , verbose    = False
                                 , urlSource  = GHCupURL
                                 , noNetwork  = False
+                                , gpgSetting = GPGNone
                                 , ..
                                 })
                       dirs
@@ -591,7 +593,7 @@ getGHCupInfo = do
 
   r <-
     flip runReaderT settings
-    . runE @'[JSONError , DownloadFailed , FileDoesNotExistError]
+    . runE @'[DigestError, GPGError, JSONError , DownloadFailed , FileDoesNotExistError]
     $ liftE
     $ getDownloadsF
 

app/ghcup/Main.hs

@@ -87,21 +87,23 @@ import qualified Text.Megaparsec.Char          as MPC
 data Options = Options
   {
   -- global options
-    optVerbose   :: Maybe Bool
+    optVerbose     :: Maybe Bool
-  , optCache     :: Maybe Bool
+  , optCache       :: Maybe Bool
-  , optUrlSource :: Maybe URI
+  , optUrlSource   :: Maybe URI
-  , optNoVerify  :: Maybe Bool
+  , optNoVerify    :: Maybe Bool
-  , optKeepDirs  :: Maybe KeepDirs
+  , optKeepDirs    :: Maybe KeepDirs
   , optsDownloader :: Maybe Downloader
-  , optNoNetwork :: Maybe Bool
+  , optNoNetwork   :: Maybe Bool
+  , optGpg         :: Maybe GPGSetting
   -- commands
-  , optCommand   :: Command
+  , optCommand     :: Command
   }
 
 data Command
   = Install (Either InstallCommand InstallOptions)
   | InstallCabalLegacy InstallOptions
   | Set (Either SetCommand SetOptions)
+  | UnSet UnsetCommand
   | List ListOptions
   | Rm (Either RmCommand RmOptions)
   | DInfo
@@ -141,6 +143,7 @@ data InstallOptions = InstallOptions
   , instBindist  :: Maybe URI
   , instSet      :: Bool
   , isolateDir   :: Maybe FilePath
+  , forceInstall :: Bool
   }
 
 data SetCommand = SetGHC SetOptions
@@ -148,6 +151,11 @@ data SetCommand = SetGHC SetOptions
                 | SetHLS SetOptions
                 | SetStack SetOptions
 
+data UnsetCommand = UnsetGHC   UnsetOptions
+                  | UnsetCabal UnsetOptions
+                  | UnsetHLS   UnsetOptions
+                  | UnsetStack UnsetOptions
+
 -- a superset of ToolVersion
 data SetToolVersion = SetToolVersion GHCTargetVersion
                     | SetToolTag Tag
@@ -158,6 +166,10 @@ data SetOptions = SetOptions
   { sToolVer :: SetToolVersion
   }
 
+data UnsetOptions = UnsetOptions
+  { sToolVer :: Maybe Text -- target platform triple
+  }
+
 data ListOptions = ListOptions
   { loTool     :: Maybe Tool
   , lCriteria  :: Maybe ListCriteria
@@ -309,6 +321,13 @@ opts =
           <> hidden
           ))
     <*> invertableSwitch "offline" 'o' False (help "Don't do any network calls, trying cached assets and failing if missing.")
+    <*> optional (option
+          (eitherReader gpgParser)
+          (  long "gpg"
+          <> metavar "<strict|lax|none>"
+          <> help
+          "GPG verification (default: none)"
+          ))
     <*> com
  where
   parseUri s' =
@@ -348,6 +367,14 @@ com =
              <> footerDoc (Just $ text setFooter)
              )
            )
+      <> command
+           "unset"
+           (info
+             (UnSet <$> unsetParser <**> helper)
+             (  progDesc "Unset currently active GHC/cabal version"
+             <> footerDoc (Just $ text unsetFooter)
+             )
+           )
       <> command
            "rm"
            (info
@@ -461,6 +488,10 @@ com =
   is given, sets GHC to 'recommended' version).
   It is recommended to always specify a subcommand (ghc/cabal/hls/stack).|]
 
+  unsetFooter :: String
+  unsetFooter = [s|Discussion:
+  Unsets the currently active GHC or cabal version.|]
+
   rmFooter :: String
   rmFooter = [s|Discussion:
   Remove the given GHC or cabal version. When no command is given,
@@ -602,7 +633,7 @@ Examples:
 
 installOpts :: Maybe Tool -> Parser InstallOptions
 installOpts tool =
-  (\p (u, v) b is -> InstallOptions v p u b is)
+  (\p (u, v) b is f -> InstallOptions v p u b is f)
     <$> optional
           (option
             (eitherReader platformParser)
@@ -640,6 +671,9 @@ installOpts tool =
            <> help "install in an isolated dir instead of the default one"
            )
           )
+    <*> switch
+          (short 'f' <> long "force" <> help "Force install")
+          
 
 
 setParser :: Parser (Either SetCommand SetOptions)
@@ -703,12 +737,74 @@ setParser =
   setHLSFooter = [s|Discussion:
     Sets the the current haskell-language-server version.|]
 
+unsetParser :: Parser UnsetCommand
+unsetParser =
+  (subparser
+      (  command
+          "ghc"
+          (   UnsetGHC
+          <$> info
+                (unsetOpts <**> helper)
+                (  progDesc "Unset GHC version"
+                <> footerDoc (Just $ text unsetGHCFooter)
+                )
+          )
+      <> command
+           "cabal"
+           (   UnsetCabal
+           <$> info
+                (unsetOpts <**> helper)
+                 (  progDesc "Unset Cabal version"
+                 <> footerDoc (Just $ text unsetCabalFooter)
+                 )
+           )
+      <> command
+           "hls"
+           (   UnsetHLS
+           <$> info
+                 (unsetOpts <**> helper)
+                 (  progDesc "Unset haskell-language-server version"
+                 <> footerDoc (Just $ text unsetHLSFooter)
+                 )
+           )
+      <> command
+           "stack"
+           (   UnsetStack
+           <$> info
+                 (unsetOpts <**> helper)
+                 (  progDesc "Unset stack version"
+                 <> footerDoc (Just $ text unsetStackFooter)
+                 )
+           )
+      )
+    )
+ where
+  unsetGHCFooter :: String
+  unsetGHCFooter = [s|Discussion:
+    Unsets the the current GHC version. That means there won't
+    be a ~/.ghcup/bin/ghc anymore.|]
+
+  unsetCabalFooter :: String
+  unsetCabalFooter = [s|Discussion:
+    Unsets the the current Cabal version.|]
+
+  unsetStackFooter :: String
+  unsetStackFooter = [s|Discussion:
+    Unsets the the current Stack version.|]
+
+  unsetHLSFooter :: String
+  unsetHLSFooter = [s|Discussion:
+    Unsets the the current haskell-language-server version.|]
+
 
 setOpts :: Maybe Tool -> Parser SetOptions
 setOpts tool = SetOptions <$>
     (fromMaybe SetRecommended <$>
       optional (setVersionArgument (Just ListInstalled) tool))
 
+unsetOpts :: Parser UnsetOptions
+unsetOpts = UnsetOptions . fmap T.pack <$> optional (argument str (metavar "TRIPLE"))
+
 listOpts :: Parser ListOptions
 listOpts =
   ListOptions
@@ -1141,7 +1237,7 @@ tagCompleter tool add = listIOCompleter $ do
         , rawOutter    = mempty
         }
   let appState = LeanAppState
-        (Settings True False Never Curl False GHCupURL True)
+        (Settings True False Never Curl False GHCupURL True GPGNone)
         dirs'
         defaultKeyBindings
         loggerConfig
@@ -1166,7 +1262,7 @@ versionCompleter criteria tool = listIOCompleter $ do
         , colorOutter  = mempty
         , rawOutter    = mempty
         }
-  let settings = Settings True False Never Curl False GHCupURL True
+  let settings = Settings True False Never Curl False GHCupURL True GPGNone
   let leanAppState = LeanAppState
                    settings
                    dirs'
@@ -1253,6 +1349,13 @@ downloaderParser s' | t == T.pack "curl"     = Right Curl
                     | otherwise = Left ("Unknown downloader value: " <> s')
   where t = T.toLower (T.pack s')
 
+gpgParser :: String -> Either String GPGSetting
+gpgParser s' | t == T.pack "strict" = Right GPGStrict
+             | t == T.pack "lax"    = Right GPGLax
+             | t == T.pack "none"   = Right GPGNone
+             | otherwise = Left ("Unknown gpg setting value: " <> s')
+  where t = T.toLower (T.pack s')
+
 
 platformParser :: String -> Either String PlatformRequest
 platformParser s' = case MP.parse (platformP <* MP.eof) "" (T.pack s') of
@@ -1332,6 +1435,7 @@ toSettings options = do
          keyBindings = maybe defaultKeyBindings mergeKeys uKeyBindings
          urlSource   = maybe (fromMaybe GHCupURL uUrlSource) OwnSource optUrlSource
          noNetwork   = fromMaybe (fromMaybe False uNoNetwork) optNoNetwork
+         gpgSetting  = fromMaybe (fromMaybe GPGNone uGPGSetting) optGpg
      in (Settings {..}, keyBindings)
 #if defined(INTERNAL_DOWNLOADER)
    defaultDownloader = Internal
@@ -1367,7 +1471,8 @@ updateSettings config settings = do
          verbose'    = fromMaybe verbose uVerbose
          urlSource'  = fromMaybe urlSource uUrlSource
          noNetwork'  = fromMaybe noNetwork uNoNetwork
-     in Settings cache' noVerify' keepDirs' downloader' verbose' urlSource' noNetwork'
+         gpgSetting' = fromMaybe gpgSetting uGPGSetting
+     in Settings cache' noVerify' keepDirs' downloader' verbose' urlSource' noNetwork' gpgSetting'
 
 upgradeOptsP :: Parser UpgradeOpts
 upgradeOptsP =
@@ -1392,7 +1497,7 @@ describe_result = $( LitE . StringL <$>
                      runIO (do
                              CapturedProcess{..} <-  do
                               dirs <- liftIO getAllDirs
-                              let settings = AppState (Settings True False Never Curl False GHCupURL False)
+                              let settings = AppState (Settings True False Never Curl False GHCupURL False GPGNone)
                                                dirs
                                                defaultKeyBindings
                               flip runReaderT settings $ executeOut "git" ["describe"] Nothing
@@ -1502,7 +1607,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
 
                 ghcupInfo <-
                   ( flip runReaderT leanAppstate
-                    . runE @'[JSONError , DownloadFailed, FileDoesNotExistError]
+                    . runE @'[DigestError, GPGError, JSONError , DownloadFailed, FileDoesNotExistError]
                     $ liftE
                     $ getDownloadsF
                     )
@@ -1575,6 +1680,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                       , BuildFailed
                       , TagNotFound
                       , DigestError
+                      , GPGError
                       , DownloadFailed
                       , TarDirDoesNotExist
                       , NextVerNotFound
@@ -1607,6 +1713,11 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                     , NoToolVersionSet
                     ]
 
+            runUnsetGHC =
+                runAppState
+                . runE
+                  @'[ NotInstalled ]
+
           let
             runLeanSetCabal =
                 runLeanAppState
@@ -1665,6 +1776,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                     @'[ AlreadyInstalled
                       , BuildFailed
                       , DigestError
+                      , GPGError
                       , DownloadFailed
                       , GHCupSetError
                       , NoDownload
@@ -1703,6 +1815,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                   . runResourceT
                   . runE
                     @'[ DigestError
+                      , GPGError
                       , NoDownload
                       , NoUpdate
                       , FileDoesNotExistError
@@ -1719,6 +1832,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                       , NoToolVersionSet
                       , NoDownload
                       , DigestError
+                      , GPGError
                       , DownloadFailed
                       , JSONError
                       , FileDoesNotExistError
@@ -1733,7 +1847,10 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                 (case instBindist of
                    Nothing -> runInstTool instPlatform $ do
                      (v, vi) <- liftE $ fromVersion instVer GHC
-                     liftE $ installGHCBin (_tvVersion v) isolateDir
+                     liftE $ installGHCBin
+                               (_tvVersion v)
+                               isolateDir
+                               forceInstall
                      when instSet $ void $ liftE $ setGHC v SetGHCOnly
                      pure vi
                    Just uri -> do
@@ -1741,9 +1858,10 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                      runInstTool' s'{ settings = settings {noVerify = True}} instPlatform $ do
                        (v, vi) <- liftE $ fromVersion instVer GHC
                        liftE $ installGHCBindist
-                         (DownloadInfo uri (Just $ RegexDir "ghc-.*") "")
+                                 (DownloadInfo uri (Just $ RegexDir "ghc-.*") "")
-                         (_tvVersion v)
+                                 (_tvVersion v)
-                         isolateDir
+                                 isolateDir
+                                 forceInstall
                        when instSet $ void $ liftE $ setGHC v SetGHCOnly
                        pure vi
                   )
@@ -1755,8 +1873,12 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                             pure ExitSuccess
                           VLeft (V (AlreadyInstalled _ v)) -> do
                             runLogger $ logWarn $
-                              "GHC ver " <> prettyVer v <> " already installed; if you really want to reinstall it, you may want to run 'ghcup rm ghc " <> prettyVer v <> "' first"
+                              "GHC ver " <> prettyVer v <> " already installed; if you really want to reinstall it, you may want to run 'ghcup install ghc --force " <> prettyVer v <> "'"
                             pure ExitSuccess
+                          VLeft (V (DirNotEmpty fp)) -> do
+                            runLogger $ logWarn $
+                              "Install directory " <> T.pack fp <> " is not empty. Use 'ghcup install ghc --isolate " <> T.pack fp <> " --force ..." <> "' to install regardless."
+                            pure $ ExitFailure 3
                           VLeft err@(V (BuildFailed tmpdir _)) -> do
                             case keepDirs settings of
                               Never -> runLogger $ (logError $ T.pack $ prettyShow err)
@@ -1775,16 +1897,20 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                 (case instBindist of
                    Nothing -> runInstTool instPlatform $ do
                      (v, vi) <- liftE $ fromVersion instVer Cabal
-                     liftE $ installCabalBin (_tvVersion v) isolateDir
+                     liftE $ installCabalBin
+                               (_tvVersion v)
+                               isolateDir
+                               forceInstall
                      pure vi
                    Just uri -> do
                      s' <- appState
                      runInstTool' s'{ settings = settings { noVerify = True}} instPlatform $ do
                        (v, vi) <- liftE $ fromVersion instVer Cabal
-                       liftE $ installCabalBindist
+                       liftE $ installCabalBindist 
-                           (DownloadInfo uri Nothing "")
+                                 (DownloadInfo uri Nothing "")
-                           (_tvVersion v)
+                                 (_tvVersion v)
-                           isolateDir
+                                 isolateDir
+                                 forceInstall
                        pure vi
                   )
                   >>= \case
@@ -1795,8 +1921,12 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                           pure ExitSuccess
                         VLeft (V (AlreadyInstalled _ v)) -> do
                           runLogger $ logWarn $
-                            "Cabal ver " <> prettyVer v <> " already installed; if you really want to reinstall it, you may want to run 'ghcup rm cabal " <> prettyVer v <> "' first"
+                            "Cabal ver " <> prettyVer v <> " already installed; if you really want to reinstall it, you may want to run 'ghcup install cabal --force " <> prettyVer v <> "'"
                           pure ExitSuccess
+                        VLeft (V (FileAlreadyExistsError fp)) -> do
+                          runLogger $ logWarn $
+                            "File " <> T.pack fp <> " already exists. Use 'ghcup install cabal --isolate " <> T.pack fp <> " --force ..." <> "' if you want to overwrite."
+                          pure $ ExitFailure 3
                         VLeft e -> do
                           runLogger $ do
                             logError $ T.pack $ prettyShow e
@@ -1807,16 +1937,20 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                  (case instBindist of
                    Nothing -> runInstTool instPlatform $ do
                      (v, vi) <- liftE $ fromVersion instVer HLS
-                     liftE $ installHLSBin (_tvVersion v) isolateDir
+                     liftE $ installHLSBin
+                               (_tvVersion v)
+                               isolateDir
+                               forceInstall
                      pure vi
                    Just uri -> do
                      s' <- appState
                      runInstTool' s'{ settings = settings { noVerify = True}} instPlatform $ do
                        (v, vi) <- liftE $ fromVersion instVer HLS
                        liftE $ installHLSBindist
-                           (DownloadInfo uri Nothing "")
+                                 (DownloadInfo uri Nothing "")
-                           (_tvVersion v)
+                                 (_tvVersion v)
-                           isolateDir
+                                 isolateDir
+                                 forceInstall
                        pure vi
                   )
                   >>= \case
@@ -1829,10 +1963,14 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                           runLogger $ logWarn $
                               "HLS ver "
                             <> prettyVer v
-                            <> " already installed; if you really want to reinstall it, you may want to run 'ghcup rm hls "
+                            <> " already installed; if you really want to reinstall it, you may want to run 'ghcup install hls --force "
                             <> prettyVer v
-                            <> "' first"
+                            <> "'"
                           pure ExitSuccess
+                        VLeft (V (FileAlreadyExistsError fp)) -> do
+                          runLogger $ logWarn $
+                            "File " <> T.pack fp <> " already exists. Use 'ghcup install hls --isolate " <> T.pack fp <> " --force ..." <> "' if you want to overwrite."
+                          pure $ ExitFailure 3
                         VLeft e -> do
                           runLogger $ do
                             logError $ T.pack $ prettyShow e
@@ -1843,16 +1981,20 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                  (case instBindist of
                     Nothing -> runInstTool instPlatform $ do
                       (v, vi) <- liftE $ fromVersion instVer Stack
-                      liftE $ installStackBin (_tvVersion v) isolateDir
+                      liftE $ installStackBin
+                                (_tvVersion v)
+                                isolateDir
+                                forceInstall
                       pure vi
                     Just uri -> do
                       s' <- appState
                       runInstTool' s'{ settings = settings { noVerify = True}} instPlatform $ do
                         (v, vi) <- liftE $ fromVersion instVer Stack
                         liftE $ installStackBindist
-                            (DownloadInfo uri Nothing "")
+                                  (DownloadInfo uri Nothing "")
-                            (_tvVersion v)
+                                  (_tvVersion v)
-                            isolateDir
+                                  isolateDir
+                                  forceInstall
                         pure vi
                   )
                   >>= \case
@@ -1863,8 +2005,12 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                           pure ExitSuccess
                         VLeft (V (AlreadyInstalled _ v)) -> do
                           runLogger $ logWarn $
-                            "Stack ver " <> prettyVer v <> " already installed; if you really want to reinstall it, you may want to run 'ghcup rm stack " <> prettyVer v <> "' first"
+                            "Stack ver " <> prettyVer v <> " already installed; if you really want to reinstall it, you may want to run 'ghcup install stack --force " <> prettyVer v <> "'"
                           pure ExitSuccess
+                        VLeft (V (FileAlreadyExistsError fp)) -> do
+                          runLogger $ logWarn $
+                            "File " <> T.pack fp <> " already exists. Use 'ghcup install stack --isolate " <> T.pack fp <> " --force ..." <> "' if you want to overwrite."
+                          pure $ ExitFailure 3
                         VLeft e -> do
                           runLogger $ do
                             logError $ T.pack $ prettyShow e
@@ -2032,6 +2178,27 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
             Set (Left (SetHLS sopts)) -> setHLS' sopts
             Set (Left (SetStack sopts)) -> setStack' sopts
 
+            UnSet (UnsetGHC (UnsetOptions triple)) -> runUnsetGHC (unsetGHC triple)
+                  >>= \case
+                        VRight _ -> do
+                          runLogger $ logInfo "GHC successfully unset"
+                          pure ExitSuccess
+                        VLeft  e -> do
+                          runLogger $ logError $ T.pack $ prettyShow e
+                          pure $ ExitFailure 14
+            UnSet (UnsetCabal (UnsetOptions _)) -> do
+              runAppState unsetCabal
+              runLogger $ logInfo "Cabal successfully unset"
+              pure ExitSuccess
+            UnSet (UnsetHLS (UnsetOptions _)) -> do
+              runAppState unsetHLS
+              runLogger $ logInfo "HLS successfully unset"
+              pure ExitSuccess
+            UnSet (UnsetStack (UnsetOptions _)) -> do
+              runAppState unsetStack
+              runLogger $ logInfo "Stack successfully unset"
+              pure ExitSuccess
+
             List ListOptions {..} ->
               runListGHC (do
                   l <- listVersions loTool lCriteria
@@ -2099,8 +2266,12 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                         pure ExitSuccess
                       VLeft (V (AlreadyInstalled _ v)) -> do
                         runLogger $ logWarn $
-                          "GHC ver " <> prettyVer v <> " already installed; if you really want to reinstall it, you may want to run 'ghcup rm ghc " <> prettyVer v <> "' first"
+                          "GHC ver " <> prettyVer v <> " already installed; if you really want to reinstall it, you may want to run 'ghcup install ghc --force " <> prettyVer v <> "'"
                         pure ExitSuccess
+                      VLeft (V (DirNotEmpty fp)) -> do
+                        runLogger $ logWarn $
+                          "Install directory " <> T.pack fp <> " is not empty. Use 'ghcup install ghc --isolate " <> T.pack fp <> " --force ..." <> "' to install regardless."
+                        pure $ ExitFailure 3
                       VLeft err@(V (BuildFailed tmpdir _)) -> do
                         case keepDirs settings of
                           Never -> runLogger $ logError $ T.pack $ prettyShow err

data/config.yaml

@@ -8,6 +8,10 @@ verbose: False
 keep-dirs: Errors  # Always | Never | Errors
 # Which downloader to use
 downloader: Curl   # Curl | Wget | Internal
+# whether to run in offline mode
+no-network: False
+# whether/how to do gpg verification
+gpg-setting: GPGNone # GPGStrict | GPGLax | GPGNone
 
 # TUI key bindings,
 # see https://hackage.haskell.org/package/vty-5.31/docs/Graphics-Vty-Input-Events.html#t:Key

data/metadata/ghcup-0.0.6.yaml

@@ -72,7 +72,6 @@ toolRequirements:
         '( >= 7 && < 8 )':
           distroPKGs:
           - gcc
-          - gcc-c++
           - gmp
           - gmp-devel
           - make
@@ -83,7 +82,6 @@ toolRequirements:
         unknown_versioning:
           distroPKGs:
           - gcc
-          - gcc-c++
           - gmp
           - gmp-devel
           - make
@@ -96,7 +94,6 @@ toolRequirements:
         unknown_versioning:
           distroPKGs:
           - gcc
-          - gcc-c++
           - gmp
           - gmp-devel
           - make
@@ -111,14 +108,15 @@ toolRequirements:
           - binutils-gold
           - curl
           - gcc
-          - g++
           - gmp-dev
-          - ncurses-dev
+          - libc-dev
           - libffi-dev
           - make
-          - xz
+          - musl-dev
-          - tar
+          - ncurses-dev
           - perl
+          - tar
+          - xz
           notes: ''
       Linux_UnknownLinux:
         unknown_versioning:
@@ -1598,6 +1596,11 @@ ghcupDownloads:
         dlHash: f10941f16e4fbd98580ab5241b9271bb0851304560c4d5ca127e3b0e20e3076f
       viPostRemove: *ghc-post-remove
       viPreCompile: *ghc-pre-compile
+      viPostInstall: &ghc-8105-post-install |
+        GHC 8.10.5 and 8.10.6 have several issues on Darwin, e.g.
+          https://gitlab.haskell.org/ghc/ghc/-/issues/19950
+        Consider upgrading to 8.10.7 via
+          ghcup install ghc --set 8.10.7
       viArch:
         A_64:
           Linux_Debian:
@@ -1698,6 +1701,7 @@ ghcupDownloads:
         dlHash: 43afba72a533408b42c1492bd047b5e37e5f7204e41a5cedd3182cc841610ce9
       viPostRemove: *ghc-post-remove
       viPreCompile: *ghc-pre-compile
+      viPostInstall: *ghc-8105-post-install
       viArch:
         A_64:
           Linux_Debian:
@@ -2314,7 +2318,8 @@ ghcupDownloads:
               dlHash: 983ebb5b584bfa600704216a63f94b40d36a02573834e90ef1042c8472d9ad57
   HLS:
     1.1.0:
-      viTags: []
+      viTags:
+        - old
       viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#110
       viPostInstall: &hls-post-install |
         This is just the server part of your LSP configuration. Consult the README on how to
@@ -2337,7 +2342,8 @@ ghcupDownloads:
           Linux_Alpine:
             unknown_versioning: *hls-110-64
     1.2.0:
-      viTags: []
+      viTags:
+        - old
       viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#120
       viPostInstall: *hls-post-install
       viArch:
@@ -2357,9 +2363,7 @@ ghcupDownloads:
           Linux_Alpine:
             unknown_versioning: *hls-120-64
     1.3.0:
-      viTags:
+      viTags: []
-        - Recommended
-        - Latest
       viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#130
       viPostInstall: *hls-post-install
       viArch:
@@ -2378,6 +2382,46 @@ ghcupDownloads:
               dlHash: 46aac7be888e29a9907cf56698c1ce1475c148b5e6cc099513e9ef74a0520dcf
           Linux_Alpine:
             unknown_versioning: *hls-130-64
+    1.4.0:
+      viTags:
+        - Recommended
+        - Latest
+      viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#140
+      viPostInstall: *hls-post-install
+      viArch:
+        A_64:
+          Linux_UnknownLinux:
+            unknown_versioning: &hls-140-64
+              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.4.0/haskell-language-server-Linux-1.4.0.tar.gz
+              dlHash: f93c114441911ccce55649702adc9553cb4c9f953c37878321d2806a3525fee8
+          Darwin:
+            unknown_versioning:
+              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.4.0/haskell-language-server-macOS-1.4.0.tar.gz
+              dlHash: a7f0ac6be93ffb08cc239e5f5fead99b061061825f99566c1be33ee60cab62a4
+          FreeBSD:
+            unknown_versioning:
+              dlUri: https://downloads.haskell.org/ghcup/unofficial-bindists/haskell-language-server/1.4.0/haskell-language-server-freebsd-1.4.0.tar.gz
+              dlHash: 6b2ad2398ed8c3964dea017e3d5e553b54c10ba1373d7653d2edd019854f4da2
+          Windows:
+            unknown_versioning:
+              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.4.0/haskell-language-server-Windows-1.4.0.tar.gz
+              dlHash: 0ec77cee750037b7a0ede817b46a913a702821f4098c6a858bcb686cb30f7efd
+          Linux_Alpine:
+            unknown_versioning: *hls-140-64
+        A_ARM64:
+          Linux_UnknownLinux:
+            unknown_versioning:
+              dlUri: https://downloads.haskell.org/ghcup/unofficial-bindists/haskell-language-server/1.4.0/haskell-language-server-linux-aarch64-1.4.0.tar.gz
+              dlHash: 8ad97e2bf1c538e637edec194e1cd9939019955bb749cb470f34bbe5a067b001
+          Darwin:
+            unknown_versioning:
+              dlUri: https://downloads.haskell.org/ghcup/unofficial-bindists/haskell-language-server/1.4.0/haskell-language-server-macOS-aarch64-1.4.0.tar.gz
+              dlHash: 70c6fe38e987ba44c1e19173486c01f666ffb30a74cd5a7968296a5aba4c2dd0
+        A_ARM:
+          Linux_UnknownLinux:
+            unknown_versioning:
+              dlUri: https://downloads.haskell.org/ghcup/unofficial-bindists/haskell-language-server/1.4.0/haskell-language-server-linux-armv7-1.4.0.tar.gz
+              dlHash: 4a921fbca06b02f3b1c0930cec5e65e9362b603e7715680ec7b150f18bd703d6
   Stack:
     2.5.1:
       viTags:

data/metadata/ghcup-0.0.7.yaml

@@ -72,7 +72,6 @@ toolRequirements:
         '( >= 7 && < 8 )':
           distroPKGs:
           - gcc
-          - gcc-c++
           - gmp
           - gmp-devel
           - make
@@ -83,7 +82,6 @@ toolRequirements:
         unknown_versioning:
           distroPKGs:
           - gcc
-          - gcc-c++
           - gmp
           - gmp-devel
           - make
@@ -96,7 +94,6 @@ toolRequirements:
         unknown_versioning:
           distroPKGs:
           - gcc
-          - gcc-c++
           - gmp
           - gmp-devel
           - make
@@ -109,7 +106,6 @@ toolRequirements:
         unknown_versioning:
           distroPKGs:
           - gcc
-          - g++
           - gmp
           - gmp-devel
           - make
@@ -125,14 +121,15 @@ toolRequirements:
           - binutils-gold
           - curl
           - gcc
-          - g++
           - gmp-dev
-          - ncurses-dev
+          - libc-dev
           - libffi-dev
           - make
-          - xz
+          - musl-dev
-          - tar
+          - ncurses-dev
           - perl
+          - tar
+          - xz
           notes: ''
       Linux_UnknownLinux:
         unknown_versioning:
@@ -1652,6 +1649,11 @@ ghcupDownloads:
         dlHash: f10941f16e4fbd98580ab5241b9271bb0851304560c4d5ca127e3b0e20e3076f
       viPostRemove: *ghc-post-remove
       viPreCompile: *ghc-pre-compile
+      viPostInstall: &ghc-8105-post-install |
+        GHC 8.10.5 and 8.10.6 have several issues on Darwin, e.g.
+          https://gitlab.haskell.org/ghc/ghc/-/issues/19950
+        Consider upgrading to 8.10.7 via
+          ghcup install ghc --set 8.10.7
       viArch:
         A_64:
           Linux_Debian:
@@ -1754,6 +1756,7 @@ ghcupDownloads:
         dlHash: 43afba72a533408b42c1492bd047b5e37e5f7204e41a5cedd3182cc841610ce9
       viPostRemove: *ghc-post-remove
       viPreCompile: *ghc-pre-compile
+      viPostInstall: *ghc-8105-post-install
       viArch:
         A_64:
           Linux_Debian:
@@ -2376,7 +2379,8 @@ ghcupDownloads:
               dlHash: 983ebb5b584bfa600704216a63f94b40d36a02573834e90ef1042c8472d9ad57
   HLS:
     1.1.0:
-      viTags: []
+      viTags:
+        - old
       viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#110
       viPostInstall: &hls-post-install |
         This is just the server part of your LSP configuration. Consult the README on how to
@@ -2399,7 +2403,8 @@ ghcupDownloads:
           Linux_Alpine:
             unknown_versioning: *hls-110-64
     1.2.0:
-      viTags: []
+      viTags:
+        - old
       viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#120
       viPostInstall: *hls-post-install
       viArch:
@@ -2419,9 +2424,7 @@ ghcupDownloads:
           Linux_Alpine:
             unknown_versioning: *hls-120-64
     1.3.0:
-      viTags:
+      viTags: []
-        - Recommended
-        - Latest
       viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#130
       viPostInstall: *hls-post-install
       viArch:
@@ -2440,6 +2443,46 @@ ghcupDownloads:
               dlHash: 46aac7be888e29a9907cf56698c1ce1475c148b5e6cc099513e9ef74a0520dcf
           Linux_Alpine:
             unknown_versioning: *hls-130-64
+    1.4.0:
+      viTags:
+        - Recommended
+        - Latest
+      viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#140
+      viPostInstall: *hls-post-install
+      viArch:
+        A_64:
+          Linux_UnknownLinux:
+            unknown_versioning: &hls-140-64
+              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.4.0/haskell-language-server-Linux-1.4.0.tar.gz
+              dlHash: f93c114441911ccce55649702adc9553cb4c9f953c37878321d2806a3525fee8
+          Darwin:
+            unknown_versioning:
+              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.4.0/haskell-language-server-macOS-1.4.0.tar.gz
+              dlHash: a7f0ac6be93ffb08cc239e5f5fead99b061061825f99566c1be33ee60cab62a4
+          FreeBSD:
+            unknown_versioning:
+              dlUri: https://downloads.haskell.org/ghcup/unofficial-bindists/haskell-language-server/1.4.0/haskell-language-server-freebsd-1.4.0.tar.gz
+              dlHash: 6b2ad2398ed8c3964dea017e3d5e553b54c10ba1373d7653d2edd019854f4da2
+          Windows:
+            unknown_versioning:
+              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.4.0/haskell-language-server-Windows-1.4.0.tar.gz
+              dlHash: 0ec77cee750037b7a0ede817b46a913a702821f4098c6a858bcb686cb30f7efd
+          Linux_Alpine:
+            unknown_versioning: *hls-140-64
+        A_ARM64:
+          Linux_UnknownLinux:
+            unknown_versioning:
+              dlUri: https://downloads.haskell.org/ghcup/unofficial-bindists/haskell-language-server/1.4.0/haskell-language-server-linux-aarch64-1.4.0.tar.gz
+              dlHash: 8ad97e2bf1c538e637edec194e1cd9939019955bb749cb470f34bbe5a067b001
+          Darwin:
+            unknown_versioning:
+              dlUri: https://downloads.haskell.org/ghcup/unofficial-bindists/haskell-language-server/1.4.0/haskell-language-server-macOS-aarch64-1.4.0.tar.gz
+              dlHash: 70c6fe38e987ba44c1e19173486c01f666ffb30a74cd5a7968296a5aba4c2dd0
+        A_ARM:
+          Linux_UnknownLinux:
+            unknown_versioning:
+              dlUri: https://downloads.haskell.org/ghcup/unofficial-bindists/haskell-language-server/1.4.0/haskell-language-server-linux-armv7-1.4.0.tar.gz
+              dlHash: 4a921fbca06b02f3b1c0930cec5e65e9362b603e7715680ec7b150f18bd703d6
   Stack:
     2.5.1:
       viTags:

lib/GHCup.hs

@@ -121,6 +121,7 @@ fetchToolBindist :: ( MonadFail m
                  -> Maybe FilePath
                  -> Excepts
                       '[ DigestError
+                       , GPGError
                        , DownloadFailed
                        , NoDownload
                        ]
@@ -148,6 +149,7 @@ fetchGHCSrc :: ( MonadFail m
             -> Maybe FilePath
             -> Excepts
                  '[ DigestError
+                  , GPGError
                   , DownloadFailed
                   , NoDownload
                   ]
@@ -184,10 +186,12 @@ installGHCBindist :: ( MonadFail m
                   => DownloadInfo    -- ^ where/how to download
                   -> Version         -- ^ the version to install
                   -> Maybe FilePath  -- ^ isolated filepath if user passed any
+                  -> Bool            -- ^ Force install
                   -> Excepts
                        '[ AlreadyInstalled
                         , BuildFailed
                         , DigestError
+                        , GPGError
                         , DownloadFailed
                         , NoDownload
                         , NotInstalled
@@ -198,15 +202,26 @@ installGHCBindist :: ( MonadFail m
                         ]
                        m
                        ()
-installGHCBindist dlinfo ver isoFilepath = do
+installGHCBindist dlinfo ver isoFilepath forceInstall = do
   let tver = mkTVer ver
 
   lift $ logDebug $ "Requested to install GHC with " <> prettyVer ver
 
-  case isoFilepath of
+  regularGHCInstalled <- lift $ checkIfToolInstalled GHC ver
-    -- we only care for already installed errors in regular (non-isolated) installs
+  
-    Nothing -> whenM (lift $ ghcInstalled tver) (throwE $ AlreadyInstalled GHC ver)
+  if
-    _ -> pure ()
+    | not forceInstall
+    , regularGHCInstalled
+    , Nothing <- isoFilepath -> do
+        throwE $ AlreadyInstalled GHC ver
+
+    | forceInstall
+    , regularGHCInstalled
+    , Nothing <- isoFilepath -> do
+        lift $ logInfo "Removing the currently installed GHC version first!"
+        liftE $ rmGHCVer tver
+
+    | otherwise -> pure ()
 
   -- download (or use cached version)
   dl <- liftE $ downloadCached dlinfo Nothing
@@ -215,13 +230,13 @@ installGHCBindist dlinfo ver isoFilepath = do
   ghcdir <- lift $ ghcupGHCDir tver
 
   toolchainSanityChecks
-  
+
   case isoFilepath of
     Just isoDir -> do                        -- isolated install
       lift $ logInfo $ "isolated installing GHC to " <> T.pack isoDir
-      liftE $ installPackedGHC dl (view dlSubdir dlinfo) isoDir ver
+      liftE $ installPackedGHC dl (view dlSubdir dlinfo) isoDir ver forceInstall
     Nothing -> do                            -- regular install
-      liftE $ installPackedGHC dl (view dlSubdir dlinfo) ghcdir ver
+      liftE $ installPackedGHC dl (view dlSubdir dlinfo) ghcdir ver forceInstall
 
       -- make symlinks & stuff when regular install,
       liftE $ postGHCInstall tver
@@ -254,6 +269,7 @@ installPackedGHC :: ( MonadMask m
                  -> Maybe TarDir      -- ^ Subdir of the archive
                  -> FilePath          -- ^ Path to install to
                  -> Version           -- ^ The GHC version
+                 -> Bool              -- ^ Force install
                  -> Excepts
                       '[ BuildFailed
                        , UnknownArchive
@@ -261,10 +277,11 @@ installPackedGHC :: ( MonadMask m
                        , DirNotEmpty
                        , ArchiveResult
                        ] m ()
-installPackedGHC dl msubdir inst ver = do
+installPackedGHC dl msubdir inst ver forceInstall = do
   PlatformRequest {..} <- lift getPlatformReq
 
-  liftE $ installDestSanityCheck inst
+  unless forceInstall
+    (liftE $ installDestSanityCheck inst)
 
   -- unpack
   tmpUnpack <- lift mkGhcupTmpDir
@@ -275,7 +292,7 @@ installPackedGHC dl msubdir inst ver = do
   workdir <- maybe (pure tmpUnpack)
                    (liftE . intoSubdir tmpUnpack)
                    msubdir
-
+  
   liftE $ runBuildAction tmpUnpack
                          (Just inst)
                          (installUnpackedGHC workdir inst ver)
@@ -365,10 +382,12 @@ installGHCBin :: ( MonadFail m
                  )
               => Version         -- ^ the version to install
               -> Maybe FilePath  -- ^ isolated install filepath, if user passed any
+              -> Bool            -- ^ force install
               -> Excepts
                    '[ AlreadyInstalled
                     , BuildFailed
                     , DigestError
+                    , GPGError
                     , DownloadFailed
                     , NoDownload
                     , NotInstalled
@@ -379,9 +398,9 @@ installGHCBin :: ( MonadFail m
                     ]
                    m
                    ()
-installGHCBin ver isoFilepath = do
+installGHCBin ver isoFilepath forceInstall = do
   dlinfo <- liftE $ getDownloadInfo GHC ver
-  installGHCBindist dlinfo ver isoFilepath
+  installGHCBindist dlinfo ver isoFilepath forceInstall
 
 
 -- | Like 'installCabalBin', except takes the 'DownloadInfo' as
@@ -401,10 +420,12 @@ installCabalBindist :: ( MonadMask m
                     => DownloadInfo
                     -> Version
                     -> Maybe FilePath -- ^ isolated install filepath, if user provides any.
+                    -> Bool           -- ^ Force install 
                     -> Excepts
                          '[ AlreadyInstalled
                           , CopyError
                           , DigestError
+                          , GPGError
                           , DownloadFailed
                           , NoDownload
                           , NotInstalled
@@ -415,25 +436,30 @@ installCabalBindist :: ( MonadMask m
                           ]
                          m
                          ()
-installCabalBindist dlinfo ver isoFilepath = do
+installCabalBindist dlinfo ver isoFilepath forceInstall = do
   lift $ logDebug $ "Requested to install cabal version " <> prettyVer ver
 
   PlatformRequest {..} <- lift getPlatformReq
   Dirs {..} <- lift getDirs
 
-  case isoFilepath of
+  -- check if we already have a regular cabal already installed
-    Nothing -> -- for regular install check if any previous versions installed
+  regularCabalInstalled <- lift $ checkIfToolInstalled Cabal ver
-      whenM
-        (lift (cabalInstalled ver) >>= \a -> liftIO $
-          handleIO (\_ -> pure False)
-            $ fmap (\x -> a && x)
-            -- ignore when the installation is a legacy cabal (binary, not symlink)
-            $ pathIsLink (binDir </> "cabal" <> exeExt)
-        )
-        (throwE $ AlreadyInstalled Cabal ver)
 
-    _ -> pure () -- check isn't required in isolated installs
+  if
+    | not forceInstall
+    , regularCabalInstalled
+    ,  Nothing <- isoFilepath -> do
+        throwE $ AlreadyInstalled Cabal ver
+        
+    | forceInstall
+    , regularCabalInstalled
+    , Nothing <- isoFilepath -> do
+        lift $ logInfo "Removing the currently installed version first!"
+        liftE $ rmCabalVer ver
 
+    | otherwise -> pure ()
+
+               
   -- download (or use cached version)
   dl <- liftE $ downloadCached dlinfo Nothing
 
@@ -448,23 +474,24 @@ installCabalBindist dlinfo ver isoFilepath = do
   case isoFilepath of
     Just isoDir -> do             -- isolated install
       lift $ logInfo $ "isolated installing Cabal to " <> T.pack isoDir
-      liftE $ installCabalUnpacked workdir isoDir Nothing
+      liftE $ installCabalUnpacked workdir isoDir Nothing forceInstall
 
     Nothing -> do                 -- regular install
-      liftE $ installCabalUnpacked workdir binDir (Just ver)
+      liftE $ installCabalUnpacked workdir binDir (Just ver) forceInstall
 
       -- create symlink if this is the latest version for regular installs
       cVers <- lift $ fmap rights getInstalledCabals
       let lInstCabal = headMay . reverse . sort $ cVers
       when (maybe True (ver >=) lInstCabal) $ liftE $ setCabal ver
-
+      
--- | Install an unpacked cabal distribution.
+-- | Install an unpacked cabal distribution.Symbol
-installCabalUnpacked :: (MonadReader env m, HasLog env, MonadCatch m, MonadIO m)
+installCabalUnpacked :: (MonadCatch m, HasLog env, MonadIO m, MonadReader env m)
               => FilePath      -- ^ Path to the unpacked cabal bindist (where the executable resides)
               -> FilePath      -- ^ Path to install to
               -> Maybe Version -- ^ Nothing for isolated install
+              -> Bool          -- ^ Force Install
               -> Excepts '[CopyError, FileAlreadyExistsError] m ()
-installCabalUnpacked path inst mver' = do
+installCabalUnpacked path inst mver' forceInstall = do
   lift $ logInfo "Installing cabal"
   let cabalFile = "cabal"
   liftIO $ createDirRecursive' inst
@@ -473,7 +500,8 @@ installCabalUnpacked path inst mver' = do
         <> exeExt
   let destPath = inst </> destFileName
 
-  liftE $ throwIfFileAlreadyExists destPath
+  unless forceInstall          -- Overwrite it when it IS a force install
+    (liftE $ throwIfFileAlreadyExists destPath)
     
   handleIO (throwE . CopyError . show) $ liftIO $ copyFile
     (path </> cabalFile <> exeExt)
@@ -498,10 +526,12 @@ installCabalBin :: ( MonadMask m
                    )
                 => Version
                 -> Maybe FilePath -- isolated install Path, if user provided any
+                -> Bool           -- force install
                 -> Excepts
                      '[ AlreadyInstalled
                       , CopyError
                       , DigestError
+                      , GPGError
                       , DownloadFailed
                       , NoDownload
                       , NotInstalled
@@ -512,9 +542,9 @@ installCabalBin :: ( MonadMask m
                       ]
                      m
                      ()
-installCabalBin ver isoFilepath = do
+installCabalBin ver isoFilepath forceInstall = do
   dlinfo <- liftE $ getDownloadInfo Cabal ver
-  installCabalBindist dlinfo ver isoFilepath
+  installCabalBindist dlinfo ver isoFilepath forceInstall
 
 
 -- | Like 'installHLSBin, except takes the 'DownloadInfo' as
@@ -534,10 +564,12 @@ installHLSBindist :: ( MonadMask m
                   => DownloadInfo
                   -> Version
                   -> Maybe FilePath -- ^ isolated install path, if user passed any
+                  -> Bool           -- ^ Force install
                   -> Excepts
                        '[ AlreadyInstalled
                         , CopyError
                         , DigestError
+                        , GPGError
                         , DownloadFailed
                         , NoDownload
                         , NotInstalled
@@ -548,20 +580,28 @@ installHLSBindist :: ( MonadMask m
                         ]
                        m
                        ()
-installHLSBindist dlinfo ver isoFilepath = do
+installHLSBindist dlinfo ver isoFilepath forceInstall = do
   lift $ logDebug $ "Requested to install hls version " <> prettyVer ver
 
   PlatformRequest {..} <- lift getPlatformReq
   Dirs {..} <- lift getDirs
 
-  case isoFilepath of
+  regularHLSInstalled <- lift $ checkIfToolInstalled HLS ver
-    Nothing ->
-      -- we only check for already installed in regular (non-isolated) installs
-      whenM (lift (hlsInstalled ver))
-      (throwE $ AlreadyInstalled HLS ver)
 
-    _ -> pure ()
+  if
+    | not forceInstall
+    , regularHLSInstalled
+    , Nothing <- isoFilepath -> do      -- regular install
+        throwE $ AlreadyInstalled HLS ver
 
+    | forceInstall
+    , regularHLSInstalled
+    , Nothing <- isoFilepath -> do      -- regular forced install
+        lift $ logInfo "Removing the currently installed version of HLS before force installing!"
+        liftE $ rmHLSVer ver
+
+    | otherwise -> pure ()
+    
   -- download (or use cached version)
   dl <- liftE $ downloadCached dlinfo Nothing
 
@@ -576,10 +616,10 @@ installHLSBindist dlinfo ver isoFilepath = do
   case isoFilepath of
     Just isoDir -> do
       lift $ logInfo $ "isolated installing HLS to " <> T.pack isoDir
-      liftE $ installHLSUnpacked workdir isoDir Nothing
+      liftE $ installHLSUnpacked workdir isoDir Nothing forceInstall
 
     Nothing -> do
-      liftE $ installHLSUnpacked workdir binDir (Just ver)
+      liftE $ installHLSUnpacked workdir binDir (Just ver) forceInstall
 
       -- create symlink if this is the latest version in a regular install
       hlsVers <- lift $ fmap rights getInstalledHLSs
@@ -592,8 +632,9 @@ installHLSUnpacked :: (MonadReader env m, MonadFail m, HasLog env, MonadCatch m,
               => FilePath      -- ^ Path to the unpacked hls bindist (where the executable resides)
               -> FilePath      -- ^ Path to install to
               -> Maybe Version -- ^ Nothing for isolated install
+              -> Bool          -- ^ is it a force install
               -> Excepts '[CopyError, FileAlreadyExistsError] m ()
-installHLSUnpacked path inst mver' = do
+installHLSUnpacked path inst mver' forceInstall = do
   lift $ logInfo "Installing HLS"
   liftIO $ createDirRecursive' inst
 
@@ -612,7 +653,8 @@ installHLSUnpacked path inst mver' = do
     let srcPath = path </> f
     let destPath = inst </> toF
 
-    liftE $ throwIfFileAlreadyExists destPath
+    unless forceInstall   -- if it is a force install, overwrite it.
+      (liftE $ throwIfFileAlreadyExists destPath)
       
     handleIO (throwE . CopyError . show) $ liftIO $ copyFile
       srcPath
@@ -627,7 +669,8 @@ installHLSUnpacked path inst mver' = do
       srcWrapperPath = path </> wrapper <> exeExt
       destWrapperPath = inst </> toF
 
-  liftE $ throwIfFileAlreadyExists destWrapperPath
+  unless forceInstall
+    (liftE $ throwIfFileAlreadyExists destWrapperPath)
       
   handleIO (throwE . CopyError . show) $ liftIO $ copyFile
     srcWrapperPath
@@ -651,11 +694,13 @@ installHLSBin :: ( MonadMask m
                  , MonadFail m
                  )
               => Version
-              -> Maybe FilePath
+              -> Maybe FilePath  -- isolated install Dir (if any)
+              -> Bool            -- force install
               -> Excepts
                    '[ AlreadyInstalled
                     , CopyError
                     , DigestError
+                    , GPGError
                     , DownloadFailed
                     , NoDownload
                     , NotInstalled
@@ -666,9 +711,9 @@ installHLSBin :: ( MonadMask m
                     ]
                    m
                    ()
-installHLSBin ver isoFilepath = do
+installHLSBin ver isoFilepath forceInstall = do
   dlinfo <- liftE $ getDownloadInfo HLS ver
-  installHLSBindist dlinfo ver isoFilepath
+  installHLSBindist dlinfo ver isoFilepath forceInstall
 
 
 -- | Installs stack into @~\/.ghcup\/bin/stack-\<ver\>@ and
@@ -688,11 +733,13 @@ installStackBin :: ( MonadMask m
                    , MonadFail m
                    )
                 => Version
-                -> Maybe FilePath
+                -> Maybe FilePath  -- ^ isolate install Dir (if any)
+                -> Bool            -- ^ Force install
                 -> Excepts
                      '[ AlreadyInstalled
                       , CopyError
                       , DigestError
+                      , GPGError
                       , DownloadFailed
                       , NoDownload
                       , NotInstalled
@@ -703,9 +750,9 @@ installStackBin :: ( MonadMask m
                       ]
                      m
                      ()
-installStackBin ver isoFilepath = do
+installStackBin ver isoFilepath forceInstall = do
   dlinfo <- liftE $ getDownloadInfo Stack ver
-  installStackBindist dlinfo ver isoFilepath
+  installStackBindist dlinfo ver isoFilepath forceInstall
 
 
 -- | Like 'installStackBin', except takes the 'DownloadInfo' as
@@ -724,11 +771,13 @@ installStackBindist :: ( MonadMask m
                        )
                     => DownloadInfo
                     -> Version
-                    -> Maybe FilePath
+                    -> Maybe FilePath -- ^ isolate install Dir (if any)
+                    -> Bool           -- ^ Force install
                     -> Excepts
                          '[ AlreadyInstalled
                           , CopyError
                           , DigestError
+                          , GPGError
                           , DownloadFailed
                           , NoDownload
                           , NotInstalled
@@ -739,18 +788,27 @@ installStackBindist :: ( MonadMask m
                           ]
                          m
                          ()
-installStackBindist dlinfo ver isoFilepath = do
+installStackBindist dlinfo ver isoFilepath forceInstall = do
   lift $ logDebug $ "Requested to install stack version " <> prettyVer ver
 
   PlatformRequest {..} <- lift getPlatformReq
   Dirs {..} <- lift getDirs
 
-  case isoFilepath of
+  regularStackInstalled <- lift $ checkIfToolInstalled Stack ver
-    Nothing ->             -- check previous versions in case of regular installs
-      whenM (lift (stackInstalled ver))
-      (throwE $ AlreadyInstalled Stack ver)
 
-    _ -> pure ()           -- don't do shit for isolates
+  if
+    | not forceInstall
+    , regularStackInstalled
+    , Nothing <- isoFilepath -> do
+        throwE $ AlreadyInstalled Stack ver
+
+    | forceInstall
+    , regularStackInstalled
+    , Nothing <- isoFilepath -> do
+        lift $ logInfo "Removing the currently installed version of Stack first!"
+        liftE $ rmStackVer ver
+
+    | otherwise -> pure ()
 
   -- download (or use cached version)
   dl <- liftE $ downloadCached dlinfo Nothing
@@ -766,9 +824,9 @@ installStackBindist dlinfo ver isoFilepath = do
   case isoFilepath of
     Just isoDir -> do                 -- isolated install
       lift $ logInfo $ "isolated installing Stack to " <> T.pack isoDir
-      liftE $ installStackUnpacked workdir isoDir Nothing
+      liftE $ installStackUnpacked workdir isoDir Nothing forceInstall
     Nothing -> do                     -- regular install
-      liftE $ installStackUnpacked workdir binDir (Just ver)
+      liftE $ installStackUnpacked workdir binDir (Just ver) forceInstall
 
       -- create symlink if this is the latest version and a regular install
       sVers <- lift $ fmap rights getInstalledStacks
@@ -781,8 +839,9 @@ installStackUnpacked :: (MonadReader env m, HasLog env, MonadCatch m, MonadIO m)
               => FilePath      -- ^ Path to the unpacked stack bindist (where the executable resides)
               -> FilePath      -- ^ Path to install to
               -> Maybe Version -- ^ Nothing for isolated installs
+              -> Bool          -- ^ Force install
               -> Excepts '[CopyError, FileAlreadyExistsError] m ()
-installStackUnpacked path inst mver' = do
+installStackUnpacked path inst mver' forceInstall = do
   lift $ logInfo "Installing stack"
   let stackFile = "stack"
   liftIO $ createDirRecursive' inst
@@ -791,7 +850,8 @@ installStackUnpacked path inst mver' = do
                      <> exeExt
       destPath = inst </> destFileName
 
-  liftE $ throwIfFileAlreadyExists destPath
+  unless forceInstall
+    (liftE $ throwIfFileAlreadyExists destPath)
       
   handleIO (throwE . CopyError . show) $ liftIO $ copyFile
     (path </> stackFile <> exeExt)
@@ -868,6 +928,8 @@ setGHC ver sghc = do
   -- create symlink for share dir
   when (isNothing . _tvTarget $ ver) $ lift $ symlinkShareDir ghcdir verS
 
+  when (sghc == SetGHCOnly) $ lift warnAboutHlsCompatibility
+
   pure ver
 
  where
@@ -906,6 +968,17 @@ setGHC ver sghc = do
             $ createDirectoryLink targetF fullF
       _ -> pure ()
 
+unsetGHC :: ( MonadReader env m
+            , HasDirs env
+            , HasLog env
+            , MonadThrow m
+            , MonadFail m
+            , MonadIO m
+            , MonadMask m
+            )
+         => Maybe Text
+         -> Excepts '[NotInstalled] m ()
+unsetGHC = rmPlain
 
 
 -- | Set the @~\/.ghcup\/bin\/cabal@ symlink.
@@ -913,7 +986,6 @@ setCabal :: ( MonadMask m
             , MonadReader env m
             , HasDirs env
             , HasLog env
-            , MonadThrow m
             , MonadFail m
             , MonadIO m
             , MonadUnliftIO m)
@@ -937,18 +1009,24 @@ setCabal ver = do
 
   pure ()
 
-
+unsetCabal :: ( MonadMask m
+              , MonadReader env m
+              , HasDirs env
+              , MonadIO m)
+           => m ()
+unsetCabal = do
+  Dirs {..} <- getDirs
+  let cabalbin = binDir </> "cabal" <> exeExt
+  hideError doesNotExistErrorType $ rmLink cabalbin
 
 
 -- | Set the haskell-language-server symlinks.
-setHLS :: ( MonadCatch m
+setHLS :: ( MonadReader env m
-          , MonadReader env m
           , HasDirs env
           , HasLog env
-          , MonadThrow m
-          , MonadFail m
           , MonadIO m
           , MonadMask m
+          , MonadFail m
           , MonadUnliftIO m
           )
        => Version
@@ -978,9 +1056,26 @@ setHLS ver = do
 
   lift $ createLink destL wrapper
 
+  lift warnAboutHlsCompatibility
+
   pure ()
 
 
+unsetHLS :: ( MonadMask m
+            , MonadReader env m
+            , HasDirs env
+            , MonadIO m)
+         => m ()
+unsetHLS = do
+  Dirs {..} <- getDirs
+  let wrapper = binDir </> "haskell-language-server-wrapper" <> exeExt
+  bins   <- liftIO $ handleIO (\_ -> pure []) $ findFiles'
+    binDir
+    (MP.chunk "haskell-language-server-" <* pvp' <* MP.chunk (T.pack exeExt) <* MP.eof)
+  forM_ bins (hideError doesNotExistErrorType . rmLink . (binDir </>))
+  hideError doesNotExistErrorType $ rmLink wrapper
+
+
 -- | Set the @~\/.ghcup\/bin\/stack@ symlink.
 setStack :: ( MonadMask m
             , MonadReader env m
@@ -1010,6 +1105,42 @@ setStack ver = do
   pure ()
 
 
+unsetStack :: ( MonadMask m
+              , MonadReader env m
+              , HasDirs env
+              , MonadIO m)
+           => m ()
+unsetStack = do
+  Dirs {..} <- getDirs
+  let stackbin = binDir </> "stack" <> exeExt
+  hideError doesNotExistErrorType $ rmLink stackbin
+
+
+-- | Warn if the installed and set HLS is not compatible with the installed and
+-- set GHC version.
+warnAboutHlsCompatibility :: ( MonadReader env m
+                             , HasDirs env
+                             , HasLog env
+                             , MonadThrow m
+                             , MonadCatch m
+                             , MonadIO m
+                             )
+                          => m ()
+warnAboutHlsCompatibility = do
+  supportedGHC <- hlsGHCVersions
+  currentGHC   <- fmap _tvVersion <$> ghcSet Nothing
+  currentHLS   <- hlsSet
+
+  case (currentGHC, currentHLS) of
+    (Just gv, Just hv) | gv `notElem` supportedGHC -> do
+      logWarn $
+        "GHC " <> T.pack (prettyShow gv) <> " is not compatible with " <>
+        "Haskell Language Server " <> T.pack (prettyShow hv) <> "." <> "\n" <>
+        "Haskell IDE support may not work until this is fixed." <> "\n" <>
+        "Install a different HLS version, or install and set one of the following GHCs:" <> "\n" <>
+        T.pack (prettyShow supportedGHC)
+        
+    _ -> return ()
 
     ------------------
     --[ List tools ]--
@@ -1783,6 +1914,7 @@ compileGHC :: ( MonadMask m
                 '[ AlreadyInstalled
                  , BuildFailed
                  , DigestError
+                 , GPGError
                  , DownloadFailed
                  , GHCupSetError
                  , NoDownload
@@ -1908,6 +2040,7 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour had
                                (Just $ RegexDir "ghc-.*")
                                ghcdir
                                (tver ^. tvVersion)
+                               False       -- not a force install, since we already overwrite when compiling.
 
     liftIO $ B.writeFile (ghcdir </> ghcUpSrcBuiltFile) bmk
     
@@ -2229,6 +2362,8 @@ upgradeGHCup :: ( MonadMask m
              -> Excepts
                   '[ CopyError
                    , DigestError
+                   , GPGError
+                   , GPGError
                    , DownloadFailed
                    , NoDownload
                    , NoUpdate
@@ -2245,7 +2380,7 @@ upgradeGHCup mtarget force' = do
   dli   <- liftE $ getDownloadInfo GHCup latestVer
   tmp   <- lift withGHCupTmpDir
   let fn = "ghcup" <> exeExt
-  p <- liftE $ download (_dlUri dli) (Just (_dlHash dli)) tmp (Just fn) False
+  p <- liftE $ download (_dlUri dli) Nothing (Just (_dlHash dli)) tmp (Just fn) False
   let destDir = takeDirectory destFile
       destFile = fromMaybe (binDir </> fn) mtarget
   lift $ logDebug $ "mkdir -p " <> T.pack destDir
@@ -2354,6 +2489,22 @@ whereIsTool tool ver@GHCTargetVersion {..} = do
       currentRunningExecPath <- liftIO getExecutablePath
       liftIO $ canonicalizePath currentRunningExecPath
 
+-- | Doesn't work for cross GHC.
+checkIfToolInstalled :: ( MonadIO m
+                        , MonadReader env m
+                        , HasDirs env
+                        , MonadCatch m) =>
+                        Tool ->
+                        Version ->
+                        m Bool
+
+checkIfToolInstalled tool ver =
+  case tool of
+    Cabal -> cabalInstalled ver
+    HLS   -> hlsInstalled ver
+    Stack -> stackInstalled ver
+    GHC   -> ghcInstalled $ mkTVer ver
+    _     -> pure False
 
 throwIfFileAlreadyExists :: ( MonadIO m ) =>
                             FilePath ->

lib/GHCup/Download.hs

@@ -114,7 +114,7 @@ getDownloadsF :: ( FromJSONKey Tool
                  , MonadMask m
                  )
               => Excepts
-                   '[JSONError , DownloadFailed , FileDoesNotExistError]
+                   '[DigestError, GPGError, JSONError , DownloadFailed , FileDoesNotExistError]
                    m
                    GHCupInfo
 getDownloadsF = do
@@ -165,7 +165,7 @@ getBase :: ( MonadReader env m
            , MonadMask m
            )
         => URI
-        -> Excepts '[JSONError, FileDoesNotExistError] m GHCupInfo
+        -> Excepts '[GPGError, DigestError, JSONError, FileDoesNotExistError] m GHCupInfo
 getBase uri = do
   Settings { noNetwork, downloader } <- lift getSettings
 
@@ -176,7 +176,6 @@ getBase uri = do
            then pure Nothing
            else handleIO (\e -> lift (warnCache (displayException e) downloader) >> pure Nothing)
                . catchE @_ @_ @'[] (\e@(DownloadFailed _) -> lift (warnCache (prettyShow e) downloader) >> pure Nothing)
-               . reThrowAll @_ @_ @'[DownloadFailed] DownloadFailed
                . fmap Just
                . smartDl
                $ uri
@@ -234,6 +233,7 @@ getBase uri = do
           -> Excepts
                '[ DownloadFailed
                 , DigestError
+                , GPGError
                 ]
                m1
                FilePath
@@ -245,7 +245,7 @@ getBase uri = do
     Dirs { cacheDir } <- lift getDirs
 
        -- for local files, let's short-circuit and ignore access time
-    if | scheme == "file" -> liftE $ download uri' Nothing cacheDir Nothing True
+    if | scheme == "file" -> liftE $ download uri' Nothing Nothing cacheDir Nothing True
        | e -> do
           accessTime <- liftIO $ getAccessTime json_file
 
@@ -258,7 +258,7 @@ getBase uri = do
    where
     dlWithMod modTime json_file = do
       let (dir, fn) = splitFileName json_file
-      f <- liftE $ download uri' Nothing dir (Just fn) True
+      f <- liftE $ download uri' (Just $ over pathL' (<> ".sig") uri') Nothing dir (Just fn) True
       liftIO $ setModificationTime f modTime
       liftIO $ setAccessTime f modTime
       pure f
@@ -322,16 +322,17 @@ download :: ( MonadReader env m
             , MonadIO m
             )
          => URI
+         -> Maybe URI         -- ^ URI for gpg sig
          -> Maybe T.Text      -- ^ expected hash
          -> FilePath          -- ^ destination dir (ignored for file:// scheme)
          -> Maybe FilePath    -- ^ optional filename
          -> Bool              -- ^ whether to read an write etags
-         -> Excepts '[DigestError , DownloadFailed] m FilePath
+         -> Excepts '[DigestError , DownloadFailed, GPGError] m FilePath
-download uri eDigest dest mfn etags
+download uri gpgUri eDigest dest mfn etags
   | scheme == "https" = dl
   | scheme == "http"  = dl
   | scheme == "file"  = do
-      let destFile' = T.unpack . decUTF8Safe $ path
+      let destFile' = T.unpack . decUTF8Safe $ view pathL' uri
       lift $ logDebug $ "using local file: " <> T.pack destFile'
       forM_ eDigest (liftE . flip checkDigest destFile')
       pure destFile'
@@ -340,115 +341,179 @@ download uri eDigest dest mfn etags
  where
   scheme = view (uriSchemeL' % schemeBSL') uri
   dl = do
-    destFile <- liftE . reThrowAll @_ @_ @'[DownloadFailed] DownloadFailed $ getDestFile
+    baseDestFile <- liftE . reThrowAll @_ @_ @'[DownloadFailed] DownloadFailed $ getDestFile uri mfn
-    lift $ logInfo $ "downloading: " <> uri' <> " as file " <> T.pack destFile
+    lift $ logInfo $ "downloading: " <> (decUTF8Safe . serializeURIRef') uri <> " as file " <> T.pack baseDestFile
 
     -- destination dir must exist
     liftIO $ createDirRecursive' dest
 
+
     -- download
     flip onException
-         (lift $ hideError doesNotExistErrorType $ recycleFile destFile)
+         (lift $ hideError doesNotExistErrorType $ recycleFile (tmpFile baseDestFile))
-     $ catchAllE @_ @'[ProcessError, DownloadFailed, UnsupportedScheme]
+     $ catchAllE @_ @'[GPGError, ProcessError, DownloadFailed, UnsupportedScheme, DigestError] @'[DigestError, DownloadFailed, GPGError]
-          (\e ->
+          (\e' -> do
-            lift (hideError doesNotExistErrorType $ recycleFile destFile)
+            lift $ hideError doesNotExistErrorType $ recycleFile (tmpFile baseDestFile)
-              >> (throwE . DownloadFailed $ e)
+            case e' of
+              V e@GPGError {} -> throwE e
+              V e@DigestError {} -> throwE e
+              _ -> throwE (DownloadFailed e')
           ) $ do
-              Settings{ downloader, noNetwork } <- lift getSettings
+              Settings{ downloader, noNetwork, gpgSetting } <- lift getSettings
               when noNetwork $ throwE (DownloadFailed (V NoNetwork :: V '[NoNetwork]))
-              case downloader of
+              downloadAction <- case downloader of
-                Curl -> do
+                    Curl -> do
-                  o' <- liftIO getCurlOpts
+                      o' <- liftIO getCurlOpts
-                  if etags
+                      if etags
-                    then do
+                        then pure $ curlEtagsDL o'
-                      dh <- liftIO $ emptySystemTempFile "curl-header"
+                        else pure $ curlDL o'
-                      flip finally (try @_ @SomeException $ rmFile dh) $
+                    Wget -> do
-                        flip finally (try @_ @SomeException $ rmFile (destFile <.> "tmp")) $ do
+                      o' <- liftIO getWgetOpts
-                          metag <- lift $ readETag destFile
+                      if etags
-                          liftE $ lEM @_ @'[ProcessError] $ exec "curl"
+                        then pure $ wgetEtagsDL o'
-                              (o' ++ (if etags then ["--dump-header", dh] else [])
+                        else pure $ wgetDL o'
-                                  ++ maybe [] (\t -> ["-H", "If-None-Match: " <> T.unpack t]) metag
-                                  ++ ["-fL", "-o", destFile <.> "tmp", T.unpack uri']) Nothing Nothing
-                          headers <- liftIO $ T.readFile dh
-
-                          -- this nonsense is necessary, because some older versions of curl would overwrite
-                          -- the destination file when 304 is returned
-                          case fmap T.words . listToMaybe . fmap T.strip . T.lines . getLastHeader $ headers of
-                            Just (http':sc:_)
-                              | sc == "304"
-                              , T.pack "HTTP" `T.isPrefixOf` http' -> lift $ logDebug "Status code was 304, not overwriting"
-                              | T.pack "HTTP" `T.isPrefixOf` http' -> do
-                                  lift $ logDebug $ "Status code was " <> sc <> ", overwriting"
-                                  liftIO $ copyFile (destFile <.> "tmp") destFile
-                            _ -> liftE $ throwE @_ @'[DownloadFailed] (DownloadFailed (toVariantAt @0 (MalformedHeaders headers)
-                              :: V '[MalformedHeaders]))
-
-                          lift $ writeEtags destFile (parseEtags headers)
-                    else
-                      liftE $ lEM @_ @'[ProcessError] $ exec "curl" 
-                        (o' ++ ["-fL", "-o", destFile, T.unpack uri']) Nothing Nothing
-                Wget -> do
-                  destFileTemp <- liftIO $ emptySystemTempFile "wget-tmp"
-                  flip finally (try @_ @SomeException $ rmFile destFileTemp) $ do
-                    o' <- liftIO getWgetOpts
-                    if etags
-                      then do
-                        metag <- lift $ readETag destFile
-                        let opts = o' ++ maybe [] (\t -> ["--header", "If-None-Match: " <> T.unpack t]) metag
-                                      ++ ["-q", "-S", "-O", destFileTemp , T.unpack uri']
-                        CapturedProcess {_exitCode, _stdErr} <- lift $ executeOut "wget" opts Nothing
-                        case _exitCode of
-                          ExitSuccess -> do
-                            liftIO $ copyFile destFileTemp destFile
-                            lift $ writeEtags destFile (parseEtags (decUTF8Safe' _stdErr))
-                          ExitFailure i'
-                            | i' == 8
-                            , Just _ <- find (T.pack "304 Not Modified" `T.isInfixOf`) . T.lines . decUTF8Safe' $ _stdErr
-                                     -> do
-                                          lift $ logDebug "Not modified, skipping download"
-                                          lift $ writeEtags destFile (parseEtags (decUTF8Safe' _stdErr))
-                            | otherwise -> throwE (NonZeroExit i' "wget" opts)
-                      else do
-                        let opts = o' ++ ["-O", destFileTemp , T.unpack uri']
-                        liftE $ lEM @_ @'[ProcessError] $ exec "wget" opts Nothing Nothing
-                        liftIO $ copyFile destFileTemp destFile
 #if defined(INTERNAL_DOWNLOADER)
-                Internal -> do
+                    Internal -> do
-                  (https, host, fullPath, port) <- liftE $ uriToQuadruple uri
+                      if etags
-                  if etags
+                        then pure (\fp -> liftE . internalEtagsDL fp)
-                    then do
+                        else pure (\fp -> liftE . internalDL fp)
-                      metag <- lift $ readETag destFile
-                      let addHeaders = maybe mempty (\etag -> M.fromList [ (mk . E.encodeUtf8 . T.pack $ "If-None-Match"
-                                                                         , E.encodeUtf8 etag)]) metag
-                      liftE
-                        $ catchE @HTTPNotModified @'[DownloadFailed] @'[] (\(HTTPNotModified etag) -> lift $ writeEtags destFile (pure $ Just etag))
-                        $ do
-                          r <- downloadToFile https host fullPath port destFile addHeaders
-                          lift $ writeEtags destFile (pure $ decUTF8Safe <$> getHeader r "etag")
-                    else void $ liftE $ catchE @HTTPNotModified
-                                        @'[DownloadFailed]
-                                   (\e@(HTTPNotModified _) ->
-                                     throwE @_ @'[DownloadFailed] (DownloadFailed (toVariantAt @0 e :: V '[HTTPNotModified])))
-                               $ downloadToFile https host fullPath port destFile mempty
 #endif
+              liftE $ downloadAction baseDestFile uri
+              case (gpgUri, gpgSetting) of
+                (_, GPGNone) -> pure ()
+                (Just gpgUri', _) -> do
+                  gpgDestFile <- liftE . reThrowAll @_ @_ @'[DownloadFailed] DownloadFailed $ getDestFile gpgUri' Nothing
+                  liftE $ flip onException
+                       (lift $ hideError doesNotExistErrorType $ recycleFile (tmpFile gpgDestFile))
+                   $ catchAllE @_ @'[GPGError, ProcessError, UnsupportedScheme, DownloadFailed] @'[GPGError]
+                        (\e -> if gpgSetting == GPGStrict then throwE (GPGError e) else lift $ logWarn $ T.pack (prettyShow (GPGError e))
+                        ) $ do
+                      o' <- liftIO getGpgOpts
+                      lift $ logDebug $ "downloading: " <> (decUTF8Safe . serializeURIRef') gpgUri' <> " as file " <> T.pack gpgDestFile
+                      liftE $ downloadAction gpgDestFile gpgUri'
+                      lift $ logInfo $ "verifying signature of: " <> T.pack baseDestFile
+                      let args = o' ++ ["--batch", "--verify", "--quiet", "--no-tty", gpgDestFile, baseDestFile]
+                      cp <- lift $ executeOut "gpg" args Nothing
+                      case cp of
+                        CapturedProcess { _exitCode = ExitFailure i, _stdErr } -> do
+                          lift $ logDebug $ decUTF8Safe' _stdErr
+                          throwE (GPGError @'[ProcessError] (V (NonZeroExit i "gpg" args)))
+                        CapturedProcess { _stdErr } -> lift $ logDebug $ decUTF8Safe' _stdErr
+                _ -> pure ()
 
-    forM_ eDigest (liftE . flip checkDigest destFile)
+              forM_ eDigest (liftE . flip checkDigest baseDestFile)
-    pure destFile
+    pure baseDestFile
+
+  curlDL :: (MonadCatch m, MonadMask m, MonadIO m) => [String] -> FilePath -> URI -> Excepts '[ProcessError, DownloadFailed, UnsupportedScheme] m ()
+  curlDL o' destFile (decUTF8Safe . serializeURIRef' -> uri') = do
+    let destFileTemp = tmpFile destFile
+    flip finally (try @_ @SomeException $ rmFile destFileTemp) $ do
+      liftE $ lEM @_ @'[ProcessError] $ exec "curl"
+        (o' ++ ["-fL", "-o", destFileTemp, T.unpack uri']) Nothing Nothing
+      liftIO $ renameFile destFileTemp destFile
+
+  curlEtagsDL :: (MonadReader env m, HasLog env, MonadCatch m, MonadMask m, MonadIO m)
+              => [String] -> FilePath -> URI -> Excepts '[ProcessError, DownloadFailed, UnsupportedScheme] m ()
+  curlEtagsDL o' destFile (decUTF8Safe . serializeURIRef' -> uri') = do
+    let destFileTemp = tmpFile destFile
+    dh <- liftIO $ emptySystemTempFile "curl-header"
+    flip finally (try @_ @SomeException $ rmFile dh) $
+      flip finally (try @_ @SomeException $ rmFile destFileTemp) $ do
+        metag <- lift $ readETag destFile
+        liftE $ lEM @_ @'[ProcessError] $ exec "curl"
+            (o' ++ (if etags then ["--dump-header", dh] else [])
+                ++ maybe [] (\t -> ["-H", "If-None-Match: " <> T.unpack t]) metag
+                ++ ["-fL", "-o", destFileTemp, T.unpack uri']) Nothing Nothing
+        headers <- liftIO $ T.readFile dh
+
+        -- this nonsense is necessary, because some older versions of curl would overwrite
+        -- the destination file when 304 is returned
+        case fmap T.words . listToMaybe . fmap T.strip . T.lines . getLastHeader $ headers of
+          Just (http':sc:_)
+            | sc == "304"
+            , T.pack "HTTP" `T.isPrefixOf` http' -> lift $ logDebug "Status code was 304, not overwriting"
+            | T.pack "HTTP" `T.isPrefixOf` http' -> do
+                lift $ logDebug $ "Status code was " <> sc <> ", overwriting"
+                liftIO $ renameFile destFileTemp destFile
+          _ -> liftE $ throwE @_ @'[DownloadFailed] (DownloadFailed (toVariantAt @0 (MalformedHeaders headers)
+            :: V '[MalformedHeaders]))
+
+        lift $ writeEtags destFile (parseEtags headers)
+
+  wgetDL :: (MonadCatch m, MonadMask m, MonadIO m) => [String] -> FilePath -> URI -> Excepts '[ProcessError, DownloadFailed, UnsupportedScheme] m ()
+  wgetDL o' destFile (decUTF8Safe . serializeURIRef' -> uri') = do
+    let destFileTemp = tmpFile destFile
+    flip finally (try @_ @SomeException $ rmFile destFileTemp) $ do
+      let opts = o' ++ ["-O", destFileTemp , T.unpack uri']
+      liftE $ lEM @_ @'[ProcessError] $ exec "wget" opts Nothing Nothing
+      liftIO $ renameFile destFileTemp destFile
+
+
+  wgetEtagsDL :: (MonadReader env m, HasLog env, MonadCatch m, MonadMask m, MonadIO m)
+              => [String] -> FilePath -> URI -> Excepts '[ProcessError, DownloadFailed, UnsupportedScheme] m ()
+  wgetEtagsDL o' destFile (decUTF8Safe . serializeURIRef' -> uri') = do
+    let destFileTemp = tmpFile destFile
+    flip finally (try @_ @SomeException $ rmFile destFileTemp) $ do
+      metag <- lift $ readETag destFile
+      let opts = o' ++ maybe [] (\t -> ["--header", "If-None-Match: " <> T.unpack t]) metag
+                    ++ ["-q", "-S", "-O", destFileTemp , T.unpack uri']
+      CapturedProcess {_exitCode, _stdErr} <- lift $ executeOut "wget" opts Nothing
+      case _exitCode of
+        ExitSuccess -> do
+          liftIO $ renameFile destFileTemp destFile
+          lift $ writeEtags destFile (parseEtags (decUTF8Safe' _stdErr))
+        ExitFailure i'
+          | i' == 8
+          , Just _ <- find (T.pack "304 Not Modified" `T.isInfixOf`) . T.lines . decUTF8Safe' $ _stdErr
+                   -> do
+                        lift $ logDebug "Not modified, skipping download"
+                        lift $ writeEtags destFile (parseEtags (decUTF8Safe' _stdErr))
+          | otherwise -> throwE (NonZeroExit i' "wget" opts)
+
+#if defined(INTERNAL_DOWNLOADER)
+  internalDL :: (MonadCatch m, MonadMask m, MonadIO m)
+             => FilePath -> URI -> Excepts '[DownloadFailed, UnsupportedScheme] m ()
+  internalDL destFile uri' = do
+    let destFileTemp = tmpFile destFile
+    flip finally (try @_ @SomeException $ rmFile destFileTemp) $ do
+      (https, host, fullPath, port) <- liftE $ uriToQuadruple uri'
+      void $ liftE $ catchE @HTTPNotModified
+                 @'[DownloadFailed]
+            (\e@(HTTPNotModified _) ->
+              throwE @_ @'[DownloadFailed] (DownloadFailed (toVariantAt @0 e :: V '[HTTPNotModified])))
+        $ downloadToFile https host fullPath port destFileTemp mempty
+      liftIO $ renameFile destFileTemp destFile
+
+
+  internalEtagsDL :: (MonadReader env m, HasLog env, MonadCatch m, MonadMask m, MonadIO m)
+                  => FilePath -> URI -> Excepts '[DownloadFailed, UnsupportedScheme] m ()
+  internalEtagsDL destFile uri' = do
+    let destFileTemp = tmpFile destFile
+    flip finally (try @_ @SomeException $ rmFile destFileTemp) $ do
+      (https, host, fullPath, port) <- liftE $ uriToQuadruple uri'
+      metag <- lift $ readETag destFile
+      let addHeaders = maybe mempty (\etag -> M.fromList [ (mk . E.encodeUtf8 . T.pack $ "If-None-Match"
+                                                         , E.encodeUtf8 etag)]) metag
+      liftE
+        $ catchE @HTTPNotModified @'[DownloadFailed] @'[] (\(HTTPNotModified etag) -> lift $ writeEtags destFile (pure $ Just etag))
+        $ do
+          r <- downloadToFile https host fullPath port destFileTemp addHeaders
+          liftIO $ renameFile destFileTemp destFile
+          lift $ writeEtags destFile (pure $ decUTF8Safe <$> getHeader r "etag")
+#endif
 
 
   -- Manage to find a file we can write the body into.
-  getDestFile :: Monad m => Excepts '[NoUrlBase] m FilePath
+  getDestFile :: Monad m => URI -> Maybe FilePath -> Excepts '[NoUrlBase] m FilePath
-  getDestFile = 
+  getDestFile uri' mfn' = 
-    case mfn of
+    let path = view pathL' uri'
+    in case mfn' of
         Just fn -> pure (dest </> fn)
         Nothing
           | let urlBase = T.unpack (decUTF8Safe (urlBaseName path))
           , not (null urlBase) -> pure (dest </> urlBase)
           -- TODO: remove this once we use hpath again
-          | otherwise -> throwE $ NoUrlBase uri'
+          | otherwise -> throwE $ NoUrlBase (decUTF8Safe . serializeURIRef' $ uri')
-
-  path = view pathL' uri
-  uri' = decUTF8Safe (serializeURIRef' uri)
 
   parseEtags :: (MonadReader env m, HasLog env, MonadIO m, MonadThrow m) => T.Text -> m (Maybe T.Text)
   parseEtags stderr = do
@@ -509,14 +574,14 @@ downloadCached :: ( MonadReader env m
                   )
                => DownloadInfo
                -> Maybe FilePath  -- ^ optional filename
-               -> Excepts '[DigestError , DownloadFailed] m FilePath
+               -> Excepts '[DigestError , DownloadFailed, GPGError] m FilePath
 downloadCached dli mfn = do
   Settings{ cache } <- lift getSettings
   case cache of
     True -> downloadCached' dli mfn Nothing
     False -> do
       tmp <- lift withGHCupTmpDir
-      liftE $ download (_dlUri dli) (Just (_dlHash dli)) tmp mfn False
+      liftE $ download (_dlUri dli) Nothing (Just (_dlHash dli)) tmp mfn False
 
 
 downloadCached' :: ( MonadReader env m
@@ -531,7 +596,7 @@ downloadCached' :: ( MonadReader env m
                 => DownloadInfo
                 -> Maybe FilePath  -- ^ optional filename
                 -> Maybe FilePath  -- ^ optional destination dir (default: cacheDir)
-                -> Excepts '[DigestError , DownloadFailed] m FilePath
+                -> Excepts '[DigestError , DownloadFailed, GPGError] m FilePath
 downloadCached' dli mfn mDestDir = do
   Dirs { cacheDir } <- lift getDirs
   let destDir = fromMaybe cacheDir mDestDir
@@ -542,7 +607,7 @@ downloadCached' dli mfn mDestDir = do
     | fileExists -> do
       liftE $ checkDigest (view dlHash dli) cachfile
       pure cachfile
-    | otherwise -> liftE $ download (_dlUri dli) (Just (_dlHash dli)) destDir mfn False
+    | otherwise -> liftE $ download (_dlUri dli) Nothing (Just (_dlHash dli)) destDir mfn False
 
 
 
@@ -589,6 +654,12 @@ getWgetOpts =
     Just r  -> pure $ splitOn " " r
     Nothing -> pure []
 
+-- | Get additional gpg args from env. This is an undocumented option.
+getGpgOpts :: IO [String]
+getGpgOpts =
+  lookupEnv "GHCUP_GPG_OPTS" >>= \case
+    Just r  -> pure $ splitOn " " r
+    Nothing -> pure []
 
 -- | Get the url base name.
 --
@@ -610,3 +681,7 @@ urlBaseName = snd . B.breakEnd (== _slash) . urlDecode False
 -- "HTTP/1.1 304 Not Modified\n"
 getLastHeader :: T.Text -> T.Text
 getLastHeader = T.unlines . lastDef [] . filter (\x -> not (null x)) . splitOn [""] . fmap T.stripEnd . T.lines
+
+
+tmpFile :: FilePath -> FilePath
+tmpFile = (<.> "tmp")

lib/GHCup/Errors.hs

@@ -195,6 +195,14 @@ instance Pretty DigestError where
   pPrint (DigestError currentDigest expectedDigest) =
     text "Digest error: expected" <+> text (T.unpack expectedDigest) <+> text "but got" <+> pPrint currentDigest
 
+-- | File digest verification failed.
+data GPGError = forall xs . (ToVariantMaybe DownloadFailed xs, PopVariant DownloadFailed xs, Show (V xs), Pretty (V xs)) => GPGError (V xs)
+
+deriving instance Show GPGError
+
+instance Pretty GPGError where
+  pPrint (GPGError reason) = text "GPG verify failed:" <+> pPrint reason
+
 -- | Unexpected HTTP status.
 data HTTPStatusError = HTTPStatusError Int (M.Map (CI ByteString) ByteString)
   deriving Show

lib/GHCup/Requirements.hs

@@ -60,9 +60,10 @@ getCommonRequirements pr tr =
 prettyRequirements :: Requirements -> T.Text
 prettyRequirements Requirements {..} =
   let d = if not . null $ _distroPKGs
-        then
+        then "\n  Please ensure the following distro packages "
-          "\n  Please install the following distro packages: "
+          <> "are installed before continuing (you can exit ghcup "
-            <> T.intercalate " " _distroPKGs
+          <> "and return at any time): "
+          <> T.intercalate " " _distroPKGs
         else ""
       n = if not . T.null $ _notes then "\n  Note: " <> _notes else ""
   in  "System requirements " <> d <> n

lib/GHCup/Types.hs

@@ -303,11 +303,12 @@ data UserSettings = UserSettings
   , uKeyBindings :: Maybe UserKeyBindings
   , uUrlSource   :: Maybe URLSource
   , uNoNetwork   :: Maybe Bool
+  , uGPGSetting  :: Maybe GPGSetting
   }
   deriving (Show, GHC.Generic)
 
 defaultUserSettings :: UserSettings
-defaultUserSettings = UserSettings Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing
+defaultUserSettings = UserSettings Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing
 
 fromSettings :: Settings -> Maybe KeyBindings -> UserSettings
 fromSettings Settings{..} Nothing =
@@ -320,6 +321,7 @@ fromSettings Settings{..} Nothing =
     , uNoNetwork = Just noNetwork
     , uKeyBindings = Nothing
     , uUrlSource = Just urlSource
+    , uGPGSetting = Just gpgSetting
   }
 fromSettings Settings{..} (Just KeyBindings{..}) =
   let ukb = UserKeyBindings
@@ -342,6 +344,7 @@ fromSettings Settings{..} (Just KeyBindings{..}) =
     , uNoNetwork = Just noNetwork
     , uKeyBindings = Just ukb
     , uUrlSource = Just urlSource
+    , uGPGSetting = Just gpgSetting
   }
 
 data UserKeyBindings = UserKeyBindings
@@ -415,6 +418,7 @@ data Settings = Settings
   , verbose    :: Bool
   , urlSource  :: URLSource
   , noNetwork  :: Bool
+  , gpgSetting :: GPGSetting
   }
   deriving (Show, GHC.Generic)
 
@@ -448,6 +452,13 @@ data Downloader = Curl
 
 instance NFData Downloader
 
+data GPGSetting = GPGStrict
+                | GPGLax
+                | GPGNone
+  deriving (Eq, Show, Ord, GHC.Generic)
+
+instance NFData GPGSetting
+
 data DebugInfo = DebugInfo
   { diBaseDir  :: FilePath
   , diBinDir   :: FilePath

lib/GHCup/Types/JSON.hs

@@ -54,6 +54,7 @@ deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''Tool
 deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''GlobalTool
 deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''KeepDirs
 deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''Downloader
+deriveJSON defaultOptions { fieldLabelModifier = removeLensFieldLabel } ''GPGSetting
 
 instance ToJSON Tag where
   toJSON Latest             = String "Latest"

lib/GHCup/Utils.hs

@@ -250,7 +250,6 @@ getInstalledGHCs = do
 -- | Get all installed cabals, by matching on @~\/.ghcup\/bin/cabal-*@.
 getInstalledCabals :: ( MonadReader env m
                       , HasDirs env
-                      , HasLog env
                       , MonadIO m
                       , MonadCatch m
                       )
@@ -268,7 +267,7 @@ getInstalledCabals = do
 
 
 -- | Whether the given cabal version is installed.
-cabalInstalled :: (HasLog env, MonadIO m, MonadReader env m, HasDirs env, MonadCatch m) => Version -> m Bool
+cabalInstalled :: (MonadIO m, MonadReader env m, HasDirs env, MonadCatch m) => Version -> m Bool
 cabalInstalled ver = do
   vers <- fmap rights getInstalledCabals
   pure $ elem ver vers
@@ -475,7 +474,7 @@ hlsGHCVersions = do
         . splitOn "~"
         )
       bins
-  pure . rights . concat . maybeToList $ vers
+  pure . sortBy (flip compare) . rights . concat . maybeToList $ vers
 
 
 -- | Get all server binaries for an hls version, if any.
@@ -1032,7 +1031,7 @@ ensureGlobalTools :: ( MonadMask m
                      , MonadUnliftIO m
                      , MonadFail m
                      )
-                  => Excepts '[DigestError , DownloadFailed, NoDownload] m ()
+                  => Excepts '[GPGError, DigestError , DownloadFailed, NoDownload] m ()
 ensureGlobalTools = do
 #if defined(IS_WINDOWS)
   (GHCupInfo _ _ gTools) <- lift getGHCupInfo
@@ -1044,8 +1043,8 @@ ensureGlobalTools = do
       lift $ logWarn "Digest doesn't match, redownloading gs.exe..."
       lift $ logDebug ("rm -f " <> T.pack (cacheDir dirs </> "gs.exe"))
       lift $ hideError doesNotExistErrorType $ recycleFile (cacheDir dirs </> "gs.exe")
-      liftE @'[DigestError , DownloadFailed] $ dl
+      liftE @'[GPGError, DigestError , DownloadFailed] $ dl
-    ) `catchE` (liftE @'[DigestError , DownloadFailed] dl)
+    ) `catchE` (liftE @'[GPGError, DigestError , DownloadFailed] dl)
   pure ()
 #else
   pure ()

lib/GHCup/Utils/File/Common.hs

@@ -9,6 +9,8 @@ import           GHCup.Utils.Prelude
 
 import           Control.Monad.Reader
 import           Data.Maybe
+import           Data.Text               ( Text )
+import           Data.Void
 import           GHC.IO.Exception
 import           Optics                  hiding ((<|), (|>))
 import           System.Directory
@@ -16,7 +18,9 @@ import           System.FilePath
 import           Text.PrettyPrint.HughesPJClass hiding ( (<>) )
 import           Text.Regex.Posix
 
+import qualified Data.Text                     as T
 import qualified Data.ByteString.Lazy          as BL
+import qualified Text.Megaparsec               as MP
 
 
 
@@ -101,6 +105,11 @@ findFiles path regex = do
   contents <- listDirectory path
   pure $ filter (match regex) contents
 
+findFiles' :: FilePath -> MP.Parsec Void Text a -> IO [FilePath]
+findFiles' path parser = do
+  contents <- listDirectory path
+  pure $ filter (\fp -> either (const False) (const True) $ MP.parse parser "" (T.pack fp)) contents
+
 
 checkFileAlreadyExists :: (MonadIO m) => FilePath -> m Bool
 checkFileAlreadyExists fp = liftIO $ doesFileExist fp

scripts/bootstrap/bootstrap-haskell

@@ -100,7 +100,7 @@ eghcup() {
 _eghcup() {
 	if [ -n "${BOOTSTRAP_HASKELL_YAML}" ] ; then
 		args="-s ${BOOTSTRAP_HASKELL_YAML}"
-	fi 
+	fi
     if [ -z "${BOOTSTRAP_HASKELL_VERBOSE}" ] ; then
         "${GHCUP_BIN}/ghcup" ${args} "$@"
     else
@@ -405,7 +405,7 @@ warn_path() {
 	echo
 	[ -n "$1" ] && warn "$1"
 	yellow "In order to run ghc and cabal, you need to adjust your PATH variable."
-	yellow "To do so, you may want run 'source $GHCUP_DIR/env' in your current terminal"
+	yellow "To do so, you may want to run 'source $GHCUP_DIR/env' in your current terminal"
 	yellow "session as well as your shell configuration (e.g. ~/.bashrc)."
 
 }
@@ -677,4 +677,3 @@ _done
 )
 
 # vim: tabstop=4 shiftwidth=4 expandtab
-