Update README badges

This reverts commit 300cfd3ba6.

.gitlab/script/ghcup_version.sh

@@ -116,7 +116,20 @@ else
 	if [ "${OS}" = "LINUX" ] ; then
 		eghcup --downloader=wget prefetch ghc 8.10.3
 		eghcup --offline install ghc 8.10.3
-	else # test wget a bit
+		if [ "${ARCH}" = "64" ] ; then
+			expected=$(cat "$( cd "$(dirname "$0")" ; pwd -P )/../ghc-8.10.3-linux.files" | sort)
+			actual=$(cd "${GHCUP_DIR}/ghc/8.10.3/" && find | sort)
+			[ "${actual}" = "${expected}" ]
+			unset actual expected
+		fi
+	elif [ "${OS}" = "WINDOWS" ] ; then
+		eghcup prefetch ghc 8.10.3
+		eghcup --offline install ghc 8.10.3
+		expected=$(cat "$( cd "$(dirname "$0")" ; pwd -P )/../ghc-8.10.3-windows.files" | sort)
+		actual=$(cd "${GHCUP_DIR}/ghc/8.10.3/" && find | sort)
+		[ "${actual}" = "${expected}" ]
+		unset actual expected
+	else
 		eghcup prefetch ghc 8.10.3
 		eghcup --offline install ghc 8.10.3
 	fi
@@ -196,6 +209,21 @@ sha3=$(sha_sum "${GHCUP_DIR}/cache/ghcup-${JSON_VERSION}.yaml")
 [ "${etag2}" = "${etag3}" ]
 [ "${sha2}" = "${sha3}" ]
 
+# test isolated installs
+eghcup install ghc -i "$(pwd)/isolated" 8.10.5
+[ "$(isolated/bin/ghc --numeric-version)" = "8.10.5" ]
+! eghcup install ghc -i "$(pwd)/isolated" 8.10.5
+if [ "${ARCH}" = "64" ] ; then
+	if [ "${OS}" = "LINUX" ] || [ "${OS}" = "WINDOWS" ] ; then
+		eghcup install cabal -i "$(pwd)/isolated" 3.4.0.0
+		[ "$(isolated/cabal --numeric-version)" = "3.4.0.0" ]
+		eghcup install stack -i "$(pwd)/isolated" 2.7.3
+		[ "$(isolated/stack --numeric-version)" = "2.7.3" ]
+		eghcup install hls -i "$(pwd)/isolated" 1.3.0
+		[ "$(isolated/haskell-language-server-wrapper --numeric-version)" = "1.3.0" ] ||
+			[ "$(isolated/haskell-language-server-wrapper --numeric-version)" = "1.3.0.0" ]
+	fi
+fi
 
 eghcup upgrade
 eghcup upgrade -f

CHANGELOG.md

@@ -1,5 +1,14 @@
 # Revision history for ghcup
 
+## 0.1.16.2 -- 2021-08-12
+
+* Add isolated installations wrt [#141](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/141) by Arjun Kathuria
+* Implement config cli MVP wrt [#134](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/134) by Oleksii Dorozhkin
+* Fix `ghcup compile ghc --flavor`
+* Fix minor installation bug causing increased disk space wrt [#139](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/139)
+* Improved error handling wrt [#136](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/136)
+* Various improvements to metadata download when using `file://` and `--offline` wrt [#137](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/137)
+
 ## 0.1.16.1 -- 2021-07-29
 
 * Add 'nuke' subcommand wrt [#135](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/135), implemented by Arjun Kathuria

README.md

@@ -6,6 +6,11 @@ Similar in scope to [rustup](https://github.com/rust-lang-nursery/rustup.rs), [p
 
 ## Table of Contents
 
+[![Join the chat at Libera.chat](https://img.shields.io/badge/chat-on%20libera%20IRC-brightgreen.svg)](https://kiwiirc.com/nextclient/irc.libera.chat/?nick=Guest%7C?#haskell,#haskell-ghcup)
+[![Join the chat at Matrix.org](https://img.shields.io/matrix/haskell-tooling:matrix.org?label=chat%20on%20matrix.org)](https://app.element.io/#/room/#haskell-tooling:matrix.org)
+[![Join the chat at Discord](https://img.shields.io/discord/280033776820813825?label=chat%20on%20discord)](https://discord.gg/pKYf3zDQU7)
+[![Join the chat at https://gitter.im/haskell/ghcup](https://badges.gitter.im/haskell/ghcup.svg)](https://gitter.im/haskell/ghcup?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+
    * [Installation](#installation)
      * [Simple bootstrap](#simple-bootstrap)
      * [Manual install](#manual-install)

app/ghcup-gen/Validate.hs

@@ -237,7 +237,7 @@ validateTarballs (TarballFilter etool versionRegex) dls gt = do
                   ($(logError) $ T.pack $ prettyShow e)
                 liftIO $ exitWith (ExitFailure 2)
 
-    let appstate = AppState (Settings True False Never Curl False GHCupURL False) dirs defaultKeyBindings (GHCupInfo mempty mempty mempty) pfreq
+    let appstate = AppState (Settings True False Never Curl True GHCupURL False) dirs defaultKeyBindings (GHCupInfo mempty mempty mempty) pfreq
 
     r <-
       runLogger

app/ghcup/BrickMain.hs

@@ -440,27 +440,29 @@ install' _ (_, ListResult {..}) = do
               , TagNotFound
               , DigestError
               , DownloadFailed
+              , DirNotEmpty
               , NoUpdate
               , TarDirDoesNotExist
+              , FileAlreadyExistsError
               ]
 
   run (do
       case lTool of
         GHC   -> do
           let vi = getVersionInfo lVer GHC dls
-          liftE $ installGHCBin lVer $> vi
+          liftE $ installGHCBin lVer Nothing $> vi
         Cabal -> do
           let vi = getVersionInfo lVer Cabal dls
-          liftE $ installCabalBin lVer $> vi
+          liftE $ installCabalBin lVer Nothing $> vi
         GHCup -> do
           let vi = snd <$> getLatest dls GHCup
           liftE $ upgradeGHCup Nothing False $> vi
         HLS   -> do
           let vi = getVersionInfo lVer HLS dls
-          liftE $ installHLSBin lVer $> vi
+          liftE $ installHLSBin lVer Nothing $> vi
         Stack -> do
           let vi = getVersionInfo lVer Stack dls
-          liftE $ installStackBin lVer $> vi
+          liftE $ installStackBin lVer Nothing $> vi
     )
     >>= \case
           VRight vi                         -> do

app/ghcup/Main.hs

@@ -78,6 +78,8 @@ import qualified Data.Map.Strict               as M
 import qualified Data.Text                     as T
 import qualified Data.Text.IO                  as T
 import qualified Data.Text.Encoding            as E
+import qualified Data.Yaml                     as Y
+import qualified Data.Yaml.Pretty              as YP
 import qualified Text.Megaparsec               as MP
 import qualified Text.Megaparsec.Char          as MPC
 
@@ -105,6 +107,7 @@ data Command
   | Rm (Either RmCommand RmOptions)
   | DInfo
   | Compile CompileCommand
+  | Config ConfigCommand
   | Whereis WhereisOptions WhereisCommand
   | Upgrade UpgradeOpts Bool
   | ToolRequirements
@@ -138,6 +141,7 @@ data InstallOptions = InstallOptions
   , instPlatform :: Maybe PlatformRequest
   , instBindist  :: Maybe URI
   , instSet      :: Bool
+  , isolateDir   :: Maybe FilePath
   }
 
 data SetCommand = SetGHC SetOptions
@@ -173,6 +177,8 @@ data RmOptions = RmOptions
 
 data CompileCommand = CompileGHC GHCCompileOptions
 
+data ConfigCommand = ShowConfig | SetConfig String String | InitConfig
+
 data GHCCompileOptions = GHCCompileOptions
   { targetGhc    :: Either Version GitBranch
   , bootstrapGhc :: Either Version FilePath
@@ -185,6 +191,7 @@ data GHCCompileOptions = GHCCompileOptions
   , ovewrwiteVer :: Maybe Version
   , buildFlavour :: Maybe String
   , hadrian      :: Bool
+  , isolateDir   :: Maybe FilePath
   }
 
 data UpgradeOpts = UpgradeInplace
@@ -408,6 +415,12 @@ com =
                   <> footerDoc (Just $ text changeLogFooter)
                   )
                )
+          <> command
+               "config"
+               (   Config
+               <$> info (configP <**> helper)
+                        (progDesc "Show or set config" <> footerDoc (Just $ text configFooter))
+               )
           <> commandGroup "Other commands:"
           <> hidden
           )
@@ -482,6 +495,17 @@ Examples:
   ghcup prefetch ghc 8.10.5
   ghcup --offline install ghc 8.10.5|]
 
+configFooter :: String
+configFooter = [s|Examples:
+
+# show current config
+ghcup config
+
+# initialize config
+ghcup config init
+
+# set <key> <value> configuration pair
+ghcup config <key> <value>|]
 
 installCabalFooter :: String
 installCabalFooter = [s|Discussion:
@@ -574,7 +598,7 @@ Examples:
 
 installOpts :: Maybe Tool -> Parser InstallOptions
 installOpts tool =
-  (\p (u, v) b -> InstallOptions v p u b)
+  (\p (u, v) b is -> InstallOptions v p u b is)
     <$> optional
           (option
             (eitherReader platformParser)
@@ -603,6 +627,15 @@ installOpts tool =
           (long "set" <> help
             "Set as active version after install"
           )
+    <*> optional
+          (option
+           (eitherReader isolateParser)
+           (  short 'i'
+           <> long "isolate"
+           <> metavar "DIR"
+           <> help "install in an isolated dir instead of the default one"
+           )
+          )
 
 
 setParser :: Parser (Either SetCommand SetOptions)
@@ -786,6 +819,19 @@ Examples:
   # build cross compiler
   ghcup compile ghc -j 4 -v 8.4.2 -b 8.2.2 -x armv7-unknown-linux-gnueabihf --config $(pwd)/build.mk -- --enable-unregisterised|]
 
+configP :: Parser ConfigCommand
+configP = subparser
+      (  command "init" initP
+      <> command "set"  setP -- [set] KEY VALUE at help lhs
+      <> command "show" showP
+      )
+    <|> argsP -- add show for a single option
+    <|> pure ShowConfig
+ where
+  initP = info (pure InitConfig) (progDesc "Write default config to ~/.ghcup/config.yaml")
+  showP = info (pure ShowConfig) (progDesc "Show current config (default)")
+  setP  = info argsP (progDesc "Set config KEY to VALUE")
+  argsP = SetConfig <$> argument str (metavar "KEY") <*> argument str (metavar "VALUE")
 
 whereisP :: Parser WhereisCommand
 whereisP = subparser
@@ -1000,6 +1046,15 @@ ghcCompileOpts =
     <*> switch
           (long "hadrian" <> help "Use the hadrian build system instead of make (only git versions seem to be properly supported atm)"
           )
+    <*> optional
+          (option
+            (eitherReader isolateParser)
+            (  short 'i'
+            <> long "isolate"
+            <> metavar "DIR"
+            <> help "install in an isolated directory instead of the default one, no symlinks to this installation will be made"
+            )
+           )
 
 
 toolVersionParser :: Parser ToolVersion
@@ -1215,6 +1270,10 @@ platformParser s' = case MP.parse (platformP <* MP.eof) "" (T.pack s') of
 bindistParser :: String -> Either String URI
 bindistParser = first show . parseURI strictURIParserOptions . UTF8.fromString
 
+isolateParser :: FilePath -> Either String FilePath
+isolateParser f = case isValid f of
+              True -> Right $ normalise f
+              False -> Left "Please enter a valid filepath for isolate dir."
 
 toSettings :: Options -> IO (Settings, KeyBindings)
 toSettings options = do
@@ -1258,6 +1317,21 @@ toSettings options = do
          , bShowAllTools = fromMaybe bShowAllTools kShowAllTools
          }
 
+updateSettings :: Monad m => UTF8.ByteString -> Settings -> Excepts '[JSONError] m Settings
+updateSettings config settings = do
+  settings' <- lE' JSONDecodeError . first show . Y.decodeEither' $ config
+  pure $ mergeConf settings' settings
+  where
+   mergeConf :: UserSettings -> Settings -> Settings
+   mergeConf UserSettings{..} Settings{..} =
+     let cache'      = fromMaybe cache uCache
+         noVerify'   = fromMaybe noVerify uNoVerify
+         keepDirs'   = fromMaybe keepDirs uKeepDirs
+         downloader' = fromMaybe downloader uDownloader
+         verbose'    = fromMaybe verbose uVerbose
+         urlSource'  = fromMaybe urlSource uUrlSource
+         noNetwork'  = fromMaybe noNetwork uNoNetwork
+     in Settings cache' noVerify' keepDirs' downloader' verbose' urlSource' noNetwork'
 
 upgradeOptsP :: Parser UpgradeOpts
 upgradeOptsP =
@@ -1292,6 +1366,11 @@ describe_result = $( LitE . StringL <$>
                      )
                    )
 
+formatConfig :: UserSettings -> String
+formatConfig settings
+  = UTF8.toString . YP.encodePretty yamlConfig $ settings
+ where
+  yamlConfig = YP.setConfCompare compare YP.defConfig
 
 main :: IO ()
 main = do
@@ -1445,6 +1524,8 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
 #endif
                       , FileDoesNotExistError
                       , CopyError
+                      , NotInstalled
+                      , DirNotEmpty
                       , NoDownload
                       , NotInstalled
                       , BuildFailed
@@ -1454,6 +1535,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                       , TarDirDoesNotExist
                       , NextVerNotFound
                       , NoToolVersionSet
+                      , FileAlreadyExistsError
                       ]
 
           let runInstTool mInstPlatform action' = do
@@ -1555,6 +1637,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                       , UnknownArchive
                       , TarDirDoesNotExist
                       , NotInstalled
+                      , DirNotEmpty
 #if !defined(TAR)
                       , ArchiveResult
 #endif
@@ -1617,22 +1700,23 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
           -----------------------
 
           let installGHC InstallOptions{..} =
-                  (case instBindist of
-                     Nothing -> runInstTool instPlatform $ do
+                (case instBindist of
+                   Nothing -> runInstTool instPlatform $ do
+                     (v, vi) <- liftE $ fromVersion instVer GHC
+                     liftE $ installGHCBin (_tvVersion v) isolateDir
+                     when instSet $ void $ liftE $ setGHC v SetGHCOnly
+                     pure vi
+                   Just uri -> do
+                     s' <- liftIO appState
+                     runInstTool' s'{ settings = settings {noVerify = True}} instPlatform $ do
                        (v, vi) <- liftE $ fromVersion instVer GHC
-                       liftE $ installGHCBin (_tvVersion v)
+                       liftE $ installGHCBindist
+                         (DownloadInfo uri (Just $ RegexDir "ghc-.*") "")
+                         (_tvVersion v)
+                         isolateDir
                        when instSet $ void $ liftE $ setGHC v SetGHCOnly
                        pure vi
-                     Just uri -> do
-                       s' <- liftIO appState
-                       runInstTool' s'{ settings = settings {noVerify = True}} instPlatform $ do
-                         (v, vi) <- liftE $ fromVersion instVer GHC
-                         liftE $ installGHCBindist
-                           (DownloadInfo uri (Just $ RegexDir "ghc-.*") "")
-                           (_tvVersion v)
-                         when instSet $ void $ liftE $ setGHC v SetGHCOnly
-                         pure vi
-                    )
+                  )
                     >>= \case
                           VRight vi -> do
                             runLogger $ $(logInfo) "GHC installation successful"
@@ -1661,7 +1745,7 @@ 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)
+                     liftE $ installCabalBin (_tvVersion v) isolateDir
                      pure vi
                    Just uri -> do
                      s' <- appState
@@ -1670,6 +1754,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                        liftE $ installCabalBindist
                            (DownloadInfo uri Nothing "")
                            (_tvVersion v)
+                           isolateDir
                        pure vi
                   )
                   >>= \case
@@ -1689,10 +1774,10 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                           pure $ ExitFailure 4
 
           let installHLS InstallOptions{..} =
-                (case instBindist of
+                 (case instBindist of
                    Nothing -> runInstTool instPlatform $ do
                      (v, vi) <- liftE $ fromVersion instVer HLS
-                     liftE $ installHLSBin (_tvVersion v)
+                     liftE $ installHLSBin (_tvVersion v) isolateDir
                      pure vi
                    Just uri -> do
                      s' <- appState
@@ -1701,6 +1786,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                        liftE $ installHLSBindist
                            (DownloadInfo uri Nothing "")
                            (_tvVersion v)
+                           isolateDir
                        pure vi
                   )
                   >>= \case
@@ -1720,19 +1806,20 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                           pure $ ExitFailure 4
 
           let installStack InstallOptions{..} =
-                (case instBindist of
-                   Nothing -> runInstTool instPlatform $ do
-                     (v, vi) <- liftE $ fromVersion instVer Stack
-                     liftE $ installStackBin (_tvVersion v)
-                     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 "")
-                           (_tvVersion v)
-                       pure vi
+                 (case instBindist of
+                    Nothing -> runInstTool instPlatform $ do
+                      (v, vi) <- liftE $ fromVersion instVer Stack
+                      liftE $ installStackBin (_tvVersion v) isolateDir
+                      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 "")
+                            (_tvVersion v)
+                            isolateDir
+                        pure vi
                   )
                   >>= \case
                         VRight vi -> do
@@ -1961,6 +2048,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                             addConfArgs
                             buildFlavour
                             hadrian
+                            isolateDir
                 GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
                 let vi = getVersionInfo (_tvVersion targetVer) GHC dls
                 when setCompile $ void $ liftE $
@@ -1990,6 +2078,37 @@ Make sure to clean up #{tmpdir} afterwards.|])
                         runLogger $ $(logError) $ T.pack $ prettyShow e
                         pure $ ExitFailure 9
 
+            Config InitConfig -> do
+              path <- getConfigFilePath
+              writeFile path $ formatConfig $ fromSettings settings (Just keybindings)
+              runLogger $ $(logDebug) [i|"config.yaml initialized at #{path}|]
+              pure ExitSuccess
+
+            Config ShowConfig -> do
+              putStrLn $ formatConfig $ fromSettings settings (Just keybindings)
+              pure ExitSuccess
+
+            Config (SetConfig k v) -> do
+              case v of
+                "" -> do
+                  runLogger $ $(logError) "Empty values are not allowed"
+                  pure $ ExitFailure 55
+                _  -> do
+                  r <- runE @'[JSONError] $ do
+                    settings' <- updateSettings [i|#{k}: #{v}\n|] settings
+                    path <- liftIO getConfigFilePath
+                    liftIO $ writeFile path $ formatConfig $ fromSettings settings' (Just keybindings)
+                    runLogger $ $(logDebug) $ T.pack $ show settings'
+                    pure ()
+
+                  case r of
+                      VRight _ -> pure ExitSuccess
+                      VLeft (V (JSONDecodeError e)) -> do
+                        runLogger $ $(logError)
+                          [i|Error decoding config: #{e}|]
+                        pure $ ExitFailure 65
+                      VLeft _ -> pure $ ExitFailure 65
+
             Whereis WhereisOptions{..} (WhereisTool tool (Just (ToolVersion v))) ->
               runLeanWhereIs (do
                 loc <- liftE $ whereIsTool tool v

bootstrap-haskell

@@ -20,7 +20,7 @@
 
 plat="$(uname -s)"
 arch=$(uname -m)
-ghver="0.1.16.1"
+ghver="0.1.16.2"
 base_url="https://downloads.haskell.org/~ghcup"
 
 export GHCUP_SKIP_UPDATE_CHECK=yes

bootstrap-haskell.ps1

@@ -371,7 +371,7 @@ if (!(Test-Path -Path ('{0}' -f $MsysDir))) {
     Exec "$Bash" '-lc' 'pacman --noconfirm -Syuu'
 
     Print-Msg -msg 'Installing Dependencies...'
-    Exec "$Bash" '-lc' 'pacman --noconfirm -S --needed curl mingw-w64-x86_64-pkgconf'
+    Exec "$Bash" '-lc' 'pacman --noconfirm -S --needed curl autoconf mingw-w64-x86_64-pkgconf'
 
     Print-Msg -msg 'Updating SSL root certificate authorities...'
     Exec "$Bash" '-lc' 'pacman --noconfirm -S ca-certificates'

ghcup-0.0.1.json

@@ -2132,7 +2132,7 @@
       }
     },
     "GHCup": {
-      "0.1.16.1": {
+      "0.1.16.2": {
         "viTags": [
           "Recommended",
           "Latest"
@@ -2143,32 +2143,32 @@
           "A_64": {
             "Linux_UnknownLinux": {
               "unknown_versioning": {
-                "dlUri": "https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-linux-ghcup-0.1.16.1",
+                "dlUri": "https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-linux-ghcup-0.1.16.2",
                 "dlSubdir": null,
-                "dlHash": "c3505d929722e245b22ec7a05267f1ae8e04089e139bbb470783eb9a1b648f83"
+                "dlHash": "d5e43b95ce1d42263376e414f7eb7c5dd440271c7c6cd9bad446fdeff3823893"
               }
             },
             "Darwin": {
               "unknown_versioning": {
-                "dlUri": "https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-apple-darwin-ghcup-0.1.16.1",
+                "dlUri": "https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-apple-darwin-ghcup-0.1.16.2",
                 "dlSubdir": null,
-                "dlHash": "7edde6bb42323232d28495abbe630321d7eb8e3827e200438a9ae4c41e531e71"
+                "dlHash": "a334620ccce7705211b2142882dde544003e6030af4b91a44c890542a90f879f"
               }
             },
             "FreeBSD": {
               "unknown_versioning": {
-                "dlUri": "https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-portbld-freebsd-ghcup-0.1.16.1",
+                "dlUri": "https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-portbld-freebsd-ghcup-0.1.16.2",
                 "dlSubdir": null,
-                "dlHash": "6b7fc3a52e859f186d30b04c823fd0c5997179222fe9aa510a33435f41599f5c"
+                "dlHash": "92359592a5694375e53b22628920086bf4bbf0faff5be018a0ed3e745a6426a9"
               }
             }
           },
           "A_32": {
             "Linux_UnknownLinux": {
               "unknown_versioning": {
-                "dlUri": "https://downloads.haskell.org/~ghcup/0.1.16.1/i386-linux-ghcup-0.1.16.1",
+                "dlUri": "https://downloads.haskell.org/~ghcup/0.1.16.2/i386-linux-ghcup-0.1.16.2",
                 "dlSubdir": null,
-                "dlHash": "93ca5d77247b6ecac01be75e9ef5454adbb503b7957b8e9c59a5abd2046aef3c"
+                "dlHash": "01968ca6decac7b6e8ba6e2c817870d3fa47289a6507e0c1ab563f7b6eec0e38"
               }
             }
           }

ghcup-0.0.2.yaml

@@ -1384,7 +1384,7 @@ ghcupDownloads:
               dlUri: https://oleg.fi/cabal-install-3.4.0.0-rc4/cabal-install-3.4.0.0-x86_64-freebsd-12.1-release.tar.xz
               dlHash: 9705e16d03497b46be4ad477e6c64d10890af853eafa8a9adf6dba89aa9e05f7
   GHCup:
-    0.1.16.1:
+    0.1.16.2:
       viTags:
       - Recommended
       - Latest
@@ -1394,22 +1394,22 @@ ghcupDownloads:
         A_64:
           Linux_UnknownLinux:
             unknown_versioning: &ghcup-64
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-linux-ghcup-0.1.16.1
-              dlHash: c3505d929722e245b22ec7a05267f1ae8e04089e139bbb470783eb9a1b648f83
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-linux-ghcup-0.1.16.2
+              dlHash: d5e43b95ce1d42263376e414f7eb7c5dd440271c7c6cd9bad446fdeff3823893
           Darwin:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-apple-darwin-ghcup-0.1.16.1
-              dlHash: 7edde6bb42323232d28495abbe630321d7eb8e3827e200438a9ae4c41e531e71
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-apple-darwin-ghcup-0.1.16.2
+              dlHash: a334620ccce7705211b2142882dde544003e6030af4b91a44c890542a90f879f
           FreeBSD:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-portbld-freebsd-ghcup-0.1.16.1
-              dlHash: 6b7fc3a52e859f186d30b04c823fd0c5997179222fe9aa510a33435f41599f5c
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-portbld-freebsd-ghcup-0.1.16.2
+              dlHash: 92359592a5694375e53b22628920086bf4bbf0faff5be018a0ed3e745a6426a9
           Linux_Alpine:
             unknown_versioning: *ghcup-64
         A_32:
           Linux_UnknownLinux:
             unknown_versioning: &ghcup-32
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/i386-linux-ghcup-0.1.16.1
-              dlHash: 93ca5d77247b6ecac01be75e9ef5454adbb503b7957b8e9c59a5abd2046aef3c
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/i386-linux-ghcup-0.1.16.2
+              dlHash: 01968ca6decac7b6e8ba6e2c817870d3fa47289a6507e0c1ab563f7b6eec0e38
           Linux_Alpine:
             unknown_versioning: *ghcup-32

ghcup-0.0.3.yaml

@@ -1451,7 +1451,7 @@ ghcupDownloads:
               dlUri: https://oleg.fi/cabal-install-3.4.0.0-rc4/cabal-install-3.4.0.0-x86_64-freebsd-12.1-release.tar.xz
               dlHash: 9705e16d03497b46be4ad477e6c64d10890af853eafa8a9adf6dba89aa9e05f7
   GHCup:
-    0.1.16.1:
+    0.1.16.2:
       viTags:
       - Recommended
       - Latest
@@ -1461,23 +1461,23 @@ ghcupDownloads:
         A_64:
           Linux_UnknownLinux:
             unknown_versioning: &ghcup-64
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-linux-ghcup-0.1.16.1
-              dlHash: c3505d929722e245b22ec7a05267f1ae8e04089e139bbb470783eb9a1b648f83
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-linux-ghcup-0.1.16.2
+              dlHash: d5e43b95ce1d42263376e414f7eb7c5dd440271c7c6cd9bad446fdeff3823893
           Darwin:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-apple-darwin-ghcup-0.1.16.1
-              dlHash: 7edde6bb42323232d28495abbe630321d7eb8e3827e200438a9ae4c41e531e71
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-apple-darwin-ghcup-0.1.16.2
+              dlHash: a334620ccce7705211b2142882dde544003e6030af4b91a44c890542a90f879f
           FreeBSD:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-portbld-freebsd-ghcup-0.1.16.1
-              dlHash: 6b7fc3a52e859f186d30b04c823fd0c5997179222fe9aa510a33435f41599f5c
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-portbld-freebsd-ghcup-0.1.16.2
+              dlHash: 92359592a5694375e53b22628920086bf4bbf0faff5be018a0ed3e745a6426a9
           Linux_Alpine:
             unknown_versioning: *ghcup-64
         A_32:
           Linux_UnknownLinux:
             unknown_versioning: &ghcup-32
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/i386-linux-ghcup-0.1.16.1
-              dlHash: 93ca5d77247b6ecac01be75e9ef5454adbb503b7957b8e9c59a5abd2046aef3c
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/i386-linux-ghcup-0.1.16.2
+              dlHash: 01968ca6decac7b6e8ba6e2c817870d3fa47289a6507e0c1ab563f7b6eec0e38
           Linux_Alpine:
             unknown_versioning: *ghcup-32
   HLS:

ghcup-0.0.4.yaml

@@ -1868,7 +1868,7 @@ ghcupDownloads:
               dlUri: https://downloads.haskell.org/~ghcup/unofficial-bindists/cabal/3.4.0.0/cabal-install-3.4.0.0-armv7-linux-bootstrapped.tar.xz
               dlHash: 16c0d1eaba24bed14f3e152970179a45d9f9bb5cc839b2c210ad06eb7d4826ed
   GHCup:
-    0.1.16.1:
+    0.1.16.2:
       viTags:
       - Recommended
       - Latest
@@ -1878,39 +1878,39 @@ ghcupDownloads:
         A_64:
           Linux_UnknownLinux:
             unknown_versioning: &ghcup-64
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-linux-ghcup-0.1.16.1
-              dlHash: c3505d929722e245b22ec7a05267f1ae8e04089e139bbb470783eb9a1b648f83
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-linux-ghcup-0.1.16.2
+              dlHash: d5e43b95ce1d42263376e414f7eb7c5dd440271c7c6cd9bad446fdeff3823893
           Darwin:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-apple-darwin-ghcup-0.1.16.1
-              dlHash: 7edde6bb42323232d28495abbe630321d7eb8e3827e200438a9ae4c41e531e71
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-apple-darwin-ghcup-0.1.16.2
+              dlHash: a334620ccce7705211b2142882dde544003e6030af4b91a44c890542a90f879f
           FreeBSD:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-portbld-freebsd-ghcup-0.1.16.1
-              dlHash: 6b7fc3a52e859f186d30b04c823fd0c5997179222fe9aa510a33435f41599f5c
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-portbld-freebsd-ghcup-0.1.16.2
+              dlHash: 92359592a5694375e53b22628920086bf4bbf0faff5be018a0ed3e745a6426a9
           Linux_Alpine:
             unknown_versioning: *ghcup-64
         A_32:
           Linux_UnknownLinux:
             unknown_versioning: &ghcup-32
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/i386-linux-ghcup-0.1.16.1
-              dlHash: 93ca5d77247b6ecac01be75e9ef5454adbb503b7957b8e9c59a5abd2046aef3c
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/i386-linux-ghcup-0.1.16.2
+              dlHash: 01968ca6decac7b6e8ba6e2c817870d3fa47289a6507e0c1ab563f7b6eec0e38
           Linux_Alpine:
             unknown_versioning: *ghcup-32
         A_ARM64:
           Linux_UnknownLinux:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/aarch64-linux-ghcup-0.1.16.1
-              dlHash: 31fecbb704e9e2474804f42817ab17bfac28e32e5aeba93ae3f4c77fbc105706
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/aarch64-linux-ghcup-0.1.16.2
+              dlHash: 0bdbfc724e0ddabb266156eea83c2c4e19c6ed79dd06db0c29b7d69df8d9fa8c
           Darwin:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/aarch64-apple-darwin-ghcup-0.1.16.1
-              dlHash: 52eb69a5693abf6c18f95a3b9bf4dac59696299d690c6397bd22a9091e76d40e
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/aarch64-apple-darwin-ghcup-0.1.16.2
+              dlHash: 8854e991a2ba1350abda59dab96ce50ae7729d1ce99399d67929ef31e90f1da5
         A_ARM:
           Linux_UnknownLinux:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/armv7-linux-ghcup-0.1.16.1
-              dlHash: 795dd2032f0f4e4ea9688cd49393aba4c40c9eae84c8dea3477f5f440f750767
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/armv7-linux-ghcup-0.1.16.2
+              dlHash: 983ebb5b584bfa600704216a63f94b40d36a02573834e90ef1042c8472d9ad57
   HLS:
     1.1.0:
       viTags:

ghcup-0.0.5.yaml

@@ -2025,7 +2025,7 @@ ghcupDownloads:
               dlUri: https://downloads.haskell.org/~ghcup/unofficial-bindists/cabal/3.4.0.0/cabal-install-3.4.0.0-armv7-linux-bootstrapped.tar.xz
               dlHash: 16c0d1eaba24bed14f3e152970179a45d9f9bb5cc839b2c210ad06eb7d4826ed
   GHCup:
-    0.1.16.1:
+    0.1.16.2:
       viTags:
       - Recommended
       - Latest
@@ -2035,43 +2035,43 @@ ghcupDownloads:
         A_64:
           Linux_UnknownLinux:
             unknown_versioning: &ghcup-64
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-linux-ghcup-0.1.16.1
-              dlHash: c3505d929722e245b22ec7a05267f1ae8e04089e139bbb470783eb9a1b648f83
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-linux-ghcup-0.1.16.2
+              dlHash: d5e43b95ce1d42263376e414f7eb7c5dd440271c7c6cd9bad446fdeff3823893
           Darwin:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-apple-darwin-ghcup-0.1.16.1
-              dlHash: 7edde6bb42323232d28495abbe630321d7eb8e3827e200438a9ae4c41e531e71
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-apple-darwin-ghcup-0.1.16.2
+              dlHash: a334620ccce7705211b2142882dde544003e6030af4b91a44c890542a90f879f
           FreeBSD:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-portbld-freebsd-ghcup-0.1.16.1
-              dlHash: 6b7fc3a52e859f186d30b04c823fd0c5997179222fe9aa510a33435f41599f5c
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-portbld-freebsd-ghcup-0.1.16.2
+              dlHash: 92359592a5694375e53b22628920086bf4bbf0faff5be018a0ed3e745a6426a9
           Windows:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-mingw64-ghcup-0.1.16.1.exe
-              dlHash: 62439b45c7bcbc1395afe948393cb8e10bbe4f3af9b1fc58ac78660c2ad616d5
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-mingw64-ghcup-0.1.16.2.exe
+              dlHash: ec78872a84213968c490675127b9aad2285980b747c68207801ae824b98c7948
           Linux_Alpine:
             unknown_versioning: *ghcup-64
         A_32:
           Linux_UnknownLinux:
             unknown_versioning: &ghcup-32
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/i386-linux-ghcup-0.1.16.1
-              dlHash: 93ca5d77247b6ecac01be75e9ef5454adbb503b7957b8e9c59a5abd2046aef3c
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/i386-linux-ghcup-0.1.16.2
+              dlHash: 01968ca6decac7b6e8ba6e2c817870d3fa47289a6507e0c1ab563f7b6eec0e38
           Linux_Alpine:
             unknown_versioning: *ghcup-32
         A_ARM64:
           Linux_UnknownLinux:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/aarch64-linux-ghcup-0.1.16.1
-              dlHash: 31fecbb704e9e2474804f42817ab17bfac28e32e5aeba93ae3f4c77fbc105706
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/aarch64-linux-ghcup-0.1.16.2
+              dlHash: 0bdbfc724e0ddabb266156eea83c2c4e19c6ed79dd06db0c29b7d69df8d9fa8c
           Darwin:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/aarch64-apple-darwin-ghcup-0.1.16.1
-              dlHash: 52eb69a5693abf6c18f95a3b9bf4dac59696299d690c6397bd22a9091e76d40e
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/aarch64-apple-darwin-ghcup-0.1.16.2
+              dlHash: 8854e991a2ba1350abda59dab96ce50ae7729d1ce99399d67929ef31e90f1da5
         A_ARM:
           Linux_UnknownLinux:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/armv7-linux-ghcup-0.1.16.1
-              dlHash: 795dd2032f0f4e4ea9688cd49393aba4c40c9eae84c8dea3477f5f440f750767
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/armv7-linux-ghcup-0.1.16.2
+              dlHash: 983ebb5b584bfa600704216a63f94b40d36a02573834e90ef1042c8472d9ad57
   HLS:
     1.1.0:
       viTags: []

ghcup-0.0.6.yaml

@@ -2025,7 +2025,7 @@ ghcupDownloads:
               dlUri: https://downloads.haskell.org/~ghcup/unofficial-bindists/cabal/3.4.0.0/cabal-install-3.4.0.0-armv7-linux-bootstrapped.tar.xz
               dlHash: 16c0d1eaba24bed14f3e152970179a45d9f9bb5cc839b2c210ad06eb7d4826ed
   GHCup:
-    0.1.16.1:
+    0.1.16.2:
       viTags:
       - Recommended
       - Latest
@@ -2035,43 +2035,43 @@ ghcupDownloads:
         A_64:
           Linux_UnknownLinux:
             unknown_versioning: &ghcup-64
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-linux-ghcup-0.1.16.1
-              dlHash: c3505d929722e245b22ec7a05267f1ae8e04089e139bbb470783eb9a1b648f83
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-linux-ghcup-0.1.16.2
+              dlHash: d5e43b95ce1d42263376e414f7eb7c5dd440271c7c6cd9bad446fdeff3823893
           Darwin:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-apple-darwin-ghcup-0.1.16.1
-              dlHash: 7edde6bb42323232d28495abbe630321d7eb8e3827e200438a9ae4c41e531e71
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-apple-darwin-ghcup-0.1.16.2
+              dlHash: a334620ccce7705211b2142882dde544003e6030af4b91a44c890542a90f879f
           FreeBSD:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-portbld-freebsd-ghcup-0.1.16.1
-              dlHash: 6b7fc3a52e859f186d30b04c823fd0c5997179222fe9aa510a33435f41599f5c
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-portbld-freebsd-ghcup-0.1.16.2
+              dlHash: 92359592a5694375e53b22628920086bf4bbf0faff5be018a0ed3e745a6426a9
           Windows:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/x86_64-mingw64-ghcup-0.1.16.1.exe
-              dlHash: 62439b45c7bcbc1395afe948393cb8e10bbe4f3af9b1fc58ac78660c2ad616d5
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-mingw64-ghcup-0.1.16.2.exe
+              dlHash: ec78872a84213968c490675127b9aad2285980b747c68207801ae824b98c7948
           Linux_Alpine:
             unknown_versioning: *ghcup-64
         A_32:
           Linux_UnknownLinux:
             unknown_versioning: &ghcup-32
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/i386-linux-ghcup-0.1.16.1
-              dlHash: 93ca5d77247b6ecac01be75e9ef5454adbb503b7957b8e9c59a5abd2046aef3c
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/i386-linux-ghcup-0.1.16.2
+              dlHash: 01968ca6decac7b6e8ba6e2c817870d3fa47289a6507e0c1ab563f7b6eec0e38
           Linux_Alpine:
             unknown_versioning: *ghcup-32
         A_ARM64:
           Linux_UnknownLinux:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/aarch64-linux-ghcup-0.1.16.1
-              dlHash: 31fecbb704e9e2474804f42817ab17bfac28e32e5aeba93ae3f4c77fbc105706
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/aarch64-linux-ghcup-0.1.16.2
+              dlHash: 0bdbfc724e0ddabb266156eea83c2c4e19c6ed79dd06db0c29b7d69df8d9fa8c
           Darwin:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/aarch64-apple-darwin-ghcup-0.1.16.1
-              dlHash: 52eb69a5693abf6c18f95a3b9bf4dac59696299d690c6397bd22a9091e76d40e
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/aarch64-apple-darwin-ghcup-0.1.16.2
+              dlHash: 8854e991a2ba1350abda59dab96ce50ae7729d1ce99399d67929ef31e90f1da5
         A_ARM:
           Linux_UnknownLinux:
             unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.1/armv7-linux-ghcup-0.1.16.1
-              dlHash: 795dd2032f0f4e4ea9688cd49393aba4c40c9eae84c8dea3477f5f440f750767
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/armv7-linux-ghcup-0.1.16.2
+              dlHash: 983ebb5b584bfa600704216a63f94b40d36a02573834e90ef1042c8472d9ad57
   HLS:
     1.1.0:
       viTags: []

ghcup.cabal

@@ -1,6 +1,6 @@
 cabal-version:   3.0
 name:            ghcup
-version:         0.1.16.1
+version:         0.1.16.2
 license:         LGPL-3.0-only
 license-file:    LICENSE
 copyright:       Julian Ospald 2020
@@ -226,6 +226,7 @@ executable ghcup
     , uri-bytestring        ^>=0.3.2.2
     , utf8-string           ^>=1.0
     , versions              >=4.0.1    && <5.1
+    , yaml                  ^>=0.11.4.0
 
   if flag(internal-downloader)
     cpp-options: -DINTERNAL_DOWNLOADER

lib/GHCup.hs

@@ -186,6 +186,7 @@ installGHCBindist :: ( MonadFail m
                      )
                   => DownloadInfo    -- ^ where/how to download
                   -> Version         -- ^ the version to install
+                  -> Maybe FilePath  -- ^ isolated filepath if user passed any
                   -> Excepts
                        '[ AlreadyInstalled
                         , BuildFailed
@@ -195,16 +196,22 @@ installGHCBindist :: ( MonadFail m
                         , NotInstalled
                         , UnknownArchive
                         , TarDirDoesNotExist
+                        , DirNotEmpty
 #if !defined(TAR)
                         , ArchiveResult
 #endif
                         ]
                        m
                        ()
-installGHCBindist dlinfo ver = do
+installGHCBindist dlinfo ver isoFilepath = do
   let tver = mkTVer ver
+
   lift $ $(logDebug) [i|Requested to install GHC with #{ver}|]
-  whenM (lift $ ghcInstalled tver) (throwE $ AlreadyInstalled GHC ver)
+
+  case isoFilepath of
+    -- we only care for already installed errors in regular (non-isolated) installs
+    Nothing -> whenM (lift $ ghcInstalled tver) (throwE $ AlreadyInstalled GHC ver)
+    _ -> pure ()
 
   -- download (or use cached version)
   dl <- liftE $ downloadCached dlinfo Nothing
@@ -214,9 +221,15 @@ installGHCBindist dlinfo ver = do
 
   toolchainSanityChecks
   
-  liftE $ installPackedGHC dl (view dlSubdir dlinfo) ghcdir ver
+  case isoFilepath of
+    Just isoDir -> do                        -- isolated install
+      lift $ $(logInfo) [i|isolated installing GHC to #{isoDir}|]
+      liftE $ installPackedGHC dl (view dlSubdir dlinfo) isoDir ver
+    Nothing -> do                            -- regular install
+      liftE $ installPackedGHC dl (view dlSubdir dlinfo) ghcdir ver
 
-  liftE $ postGHCInstall tver
+      -- make symlinks & stuff when regular install,
+      liftE $ postGHCInstall tver
 
  where
   toolchainSanityChecks = do
@@ -250,6 +263,7 @@ installPackedGHC :: ( MonadMask m
                       '[ BuildFailed
                        , UnknownArchive
                        , TarDirDoesNotExist
+                       , DirNotEmpty
 #if !defined(TAR)
                        , ArchiveResult
 #endif
@@ -257,6 +271,8 @@ installPackedGHC :: ( MonadMask m
 installPackedGHC dl msubdir inst ver = do
   PlatformRequest {..} <- lift getPlatformReq
 
+  liftE $ installDestSanityCheck inst
+
   -- unpack
   tmpUnpack <- lift mkGhcupTmpDir
   liftE $ unpackToDir tmpUnpack dl
@@ -270,6 +286,22 @@ installPackedGHC dl msubdir inst ver = do
   liftE $ runBuildAction tmpUnpack
                          (Just inst)
                          (installUnpackedGHC workdir inst ver)
+ where
+  -- | Does basic checks for isolated installs
+  -- Isolated Directory:
+  --   1. if it doesn't exist -> proceed
+  --   2. if it exists and is empty -> proceed
+  --   3. if it exists and is non-empty -> panic and leave the house
+  installDestSanityCheck :: ( MonadIO m
+                            , MonadCatch m
+                            ) =>
+                            FilePath ->
+                            Excepts '[DirNotEmpty] m ()
+  installDestSanityCheck isoDir = do
+    hideErrorDef [doesNotExistErrorType] () $ do
+      contents <- liftIO $ getDirectoryContentsRecursive isoDir
+      unless (null contents) (throwE $ DirNotEmpty isoDir)
+
 
 
 -- | Install an unpacked GHC distribution. This only deals with the GHC
@@ -300,10 +332,6 @@ installUnpackedGHC path inst ver = do
     setModificationTime dest mtime
 #else
   PlatformRequest {..} <- lift getPlatformReq
-  liftIO $ copyDirectoryRecursive path inst $ \source dest -> do
-    mtime <- getModificationTime source
-    copyFile source dest
-    setModificationTime dest mtime
 
   let alpineArgs
        | ver >= [vver|8.2.2|], Linux Alpine <- _rPlatform
@@ -343,6 +371,7 @@ installGHCBin :: ( MonadFail m
                  , MonadUnliftIO m
                  )
               => Version         -- ^ the version to install
+              -> Maybe FilePath  -- ^ isolated install filepath, if user passed any
               -> Excepts
                    '[ AlreadyInstalled
                     , BuildFailed
@@ -352,15 +381,16 @@ installGHCBin :: ( MonadFail m
                     , NotInstalled
                     , UnknownArchive
                     , TarDirDoesNotExist
+                    , DirNotEmpty
 #if !defined(TAR)
                     , ArchiveResult
 #endif
                     ]
                    m
                    ()
-installGHCBin ver = do
+installGHCBin ver isoFilepath = do
   dlinfo <- liftE $ getDownloadInfo GHC ver
-  installGHCBindist dlinfo ver
+  installGHCBindist dlinfo ver isoFilepath
 
 
 -- | Like 'installCabalBin', except takes the 'DownloadInfo' as
@@ -379,6 +409,7 @@ installCabalBindist :: ( MonadMask m
                        )
                     => DownloadInfo
                     -> Version
+                    -> Maybe FilePath -- ^ isolated install filepath, if user provides any.
                     -> Excepts
                          '[ AlreadyInstalled
                           , CopyError
@@ -391,23 +422,28 @@ installCabalBindist :: ( MonadMask m
 #if !defined(TAR)
                           , ArchiveResult
 #endif
+                          , FileAlreadyExistsError
                           ]
                          m
                          ()
-installCabalBindist dlinfo ver = do
+installCabalBindist dlinfo ver isoFilepath = do
   lift $ $(logDebug) [i|Requested to install cabal version #{ver}|]
 
   PlatformRequest {..} <- lift getPlatformReq
   Dirs {..} <- lift getDirs
 
-  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)
+  case isoFilepath of
+    Nothing -> -- for regular install check if any previous versions installed
+      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
 
   -- download (or use cached version)
   dl <- liftE $ downloadCached dlinfo Nothing
@@ -420,30 +456,37 @@ installCabalBindist dlinfo ver = do
   -- the subdir of the archive where we do the work
   workdir <- maybe (pure tmpUnpack) (liftE . intoSubdir tmpUnpack) (view dlSubdir dlinfo)
 
-  liftE $ installCabal' workdir binDir
+  case isoFilepath of
+    Just isoDir -> do             -- isolated install
+      lift $ $(logInfo) [i|isolated installing Cabal to #{isoDir}|]
+      liftE $ installCabalUnpacked workdir isoDir Nothing
 
-  -- create symlink if this is the latest version
-  cVers <- lift $ fmap rights getInstalledCabals
-  let lInstCabal = headMay . reverse . sort $ cVers
-  when (maybe True (ver >=) lInstCabal) $ liftE $ setCabal ver
+    Nothing -> do                 -- regular install
+      liftE $ installCabalUnpacked workdir binDir (Just ver)
 
- where
-  -- | Install an unpacked cabal distribution.
-  installCabal' :: (MonadLogger m, MonadCatch m, MonadIO m)
-                => FilePath      -- ^ Path to the unpacked cabal bindist (where the executable resides)
-                -> FilePath      -- ^ Path to install to
-                -> Excepts '[CopyError] m ()
-  installCabal' path inst = do
-    lift $ $(logInfo) "Installing cabal"
-    let cabalFile = "cabal"
-    liftIO $ createDirRecursive' inst
-    let destFileName = cabalFile <> "-" <> T.unpack (prettyVer ver) <> exeExt
-    let destPath = inst </> destFileName
-    handleIO (throwE . CopyError . show) $ liftIO $ copyFile
-      (path </> cabalFile <> exeExt)
-      destPath
-    lift $ chmod_755 destPath
+      -- 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.
+installCabalUnpacked :: (MonadLogger m, MonadCatch m, MonadIO m)
+              => FilePath      -- ^ Path to the unpacked cabal bindist (where the executable resides)
+              -> FilePath      -- ^ Path to install to
+              -> Maybe Version -- ^ Nothing for isolated install
+              -> Excepts '[CopyError, FileAlreadyExistsError] m ()
+installCabalUnpacked path inst mver' = do
+  lift $ $(logInfo) "Installing cabal"
+  let cabalFile = "cabal"
+  liftIO $ createDirRecursive' inst
+  let destFileName = cabalFile
+        <> maybe "" (("-" <>) . T.unpack . prettyVer) mver'
+        <> exeExt
+  let destPath = inst </> destFileName
+  handleIO (throwE . CopyError . show) $ liftIO $ copyFile
+    (path </> cabalFile <> exeExt)
+    destPath
+  lift $ chmod_755 destPath
 
 -- | Installs cabal into @~\/.ghcup\/bin/cabal-\<ver\>@ and
 -- creates a default @cabal -> cabal-x.y.z.q@ symlink for
@@ -462,6 +505,7 @@ installCabalBin :: ( MonadMask m
                    , MonadFail m
                    )
                 => Version
+                -> Maybe FilePath -- isolated install Path, if user provided any
                 -> Excepts
                      '[ AlreadyInstalled
                       , CopyError
@@ -474,12 +518,13 @@ installCabalBin :: ( MonadMask m
 #if !defined(TAR)
                       , ArchiveResult
 #endif
+                      , FileAlreadyExistsError
                       ]
                      m
                      ()
-installCabalBin ver = do
+installCabalBin ver isoFilepath = do
   dlinfo <- liftE $ getDownloadInfo Cabal ver
-  installCabalBindist dlinfo ver
+  installCabalBindist dlinfo ver isoFilepath
 
 
 -- | Like 'installHLSBin, except takes the 'DownloadInfo' as
@@ -498,6 +543,7 @@ installHLSBindist :: ( MonadMask m
                      )
                   => DownloadInfo
                   -> Version
+                  -> Maybe FilePath -- ^ isolated install path, if user passed any
                   -> Excepts
                        '[ AlreadyInstalled
                         , CopyError
@@ -513,14 +559,19 @@ installHLSBindist :: ( MonadMask m
                         ]
                        m
                        ()
-installHLSBindist dlinfo ver = do
+installHLSBindist dlinfo ver isoFilepath = do
   lift $ $(logDebug) [i|Requested to install hls version #{ver}|]
 
   PlatformRequest {..} <- lift getPlatformReq
   Dirs {..} <- lift getDirs
 
-  whenM (lift (hlsInstalled ver))
-    (throwE $ AlreadyInstalled HLS ver)
+  case isoFilepath of
+    Nothing ->
+      -- we only check for already installed in regular (non-isolated) installs
+      whenM (lift (hlsInstalled ver))
+      (throwE $ AlreadyInstalled HLS ver)
+
+    _ -> pure ()
 
   -- download (or use cached version)
   dl <- liftE $ downloadCached dlinfo Nothing
@@ -533,46 +584,55 @@ installHLSBindist dlinfo ver = do
   -- the subdir of the archive where we do the work
   workdir <- maybe (pure tmpUnpack) (liftE . intoSubdir tmpUnpack) (view dlSubdir dlinfo)
 
-  liftE $ installHLS' workdir binDir
+  case isoFilepath of
+    Just isoDir -> do
+      lift $ $(logInfo) [i|isolated installing HLS to #{isoDir}|]
+      liftE $ installHLSUnpacked workdir isoDir Nothing
 
-  -- create symlink if this is the latest version
-  hlsVers <- lift $ fmap rights getInstalledHLSs
-  let lInstHLS = headMay . reverse . sort $ hlsVers
-  when (maybe True (ver >=) lInstHLS) $ liftE $ setHLS ver
+    Nothing -> do
+      liftE $ installHLSUnpacked workdir binDir (Just ver)
 
- where
-  -- | Install an unpacked hls distribution.
-  installHLS' :: (MonadFail m, MonadLogger m, MonadCatch m, MonadIO m)
-                => FilePath      -- ^ Path to the unpacked hls bindist (where the executable resides)
-                -> FilePath      -- ^ Path to install to
-                -> Excepts '[CopyError] m ()
-  installHLS' path inst = do
-    lift $ $(logInfo) "Installing HLS"
-    liftIO $ createDirRecursive' inst
+      -- create symlink if this is the latest version in a regular install
+      hlsVers <- lift $ fmap rights getInstalledHLSs
+      let lInstHLS = headMay . reverse . sort $ hlsVers
+      when (maybe True (ver >=) lInstHLS) $ liftE $ setHLS ver
 
-    -- install haskell-language-server-<ghcver>
-    bins@(_:_) <- liftIO $ findFiles
-      path
-      (makeRegexOpts compExtended
-                     execBlank
-                     ([s|^haskell-language-server-[0-9].*$|] :: ByteString)
-      )
-    forM_ bins $ \f -> do
-      let toF = dropSuffix exeExt f
-                <> "~" <> T.unpack (prettyVer ver) <> exeExt
-      handleIO (throwE . CopyError . show) $ liftIO $ copyFile
-        (path </> f)
-        (inst </> toF)
-      lift $ chmod_755 (inst </> toF)
 
-    -- install haskell-language-server-wrapper
-    let wrapper = "haskell-language-server-wrapper"
-        toF = wrapper <> "-" <> T.unpack (prettyVer ver) <> exeExt
+-- | Install an unpacked hls distribution.
+installHLSUnpacked :: (MonadFail m, MonadLogger m, MonadCatch m, MonadIO m)
+              => FilePath      -- ^ Path to the unpacked hls bindist (where the executable resides)
+              -> FilePath      -- ^ Path to install to
+              -> Maybe Version -- ^ Nothing for isolated install
+              -> Excepts '[CopyError] m ()
+installHLSUnpacked path inst mver' = do
+  lift $ $(logInfo) "Installing HLS"
+  liftIO $ createDirRecursive' inst
+
+  -- install haskell-language-server-<ghcver>
+  bins@(_:_) <- liftIO $ findFiles
+    path
+    (makeRegexOpts compExtended
+                   execBlank
+                   ([s|^haskell-language-server-[0-9].*$|] :: ByteString)
+    )
+  forM_ bins $ \f -> do
+    let toF = dropSuffix exeExt f
+              <> maybe "" (("~" <>) . T.unpack . prettyVer) mver'
+              <> exeExt
     handleIO (throwE . CopyError . show) $ liftIO $ copyFile
-      (path </> wrapper <> exeExt)
+      (path </> f)
       (inst </> toF)
     lift $ chmod_755 (inst </> toF)
 
+  -- install haskell-language-server-wrapper
+  let wrapper = "haskell-language-server-wrapper"
+      toF = wrapper
+            <> maybe "" (("-" <>) . T.unpack . prettyVer) mver'
+            <> exeExt
+  handleIO (throwE . CopyError . show) $ liftIO $ copyFile
+    (path </> wrapper <> exeExt)
+    (inst </> toF)
+  lift $ chmod_755 (inst </> toF)
 
 -- | Installs hls binaries @haskell-language-server-\<ghcver\>@
 -- into @~\/.ghcup\/bin/@, as well as @haskell-languager-server-wrapper@.
@@ -590,6 +650,7 @@ installHLSBin :: ( MonadMask m
                  , MonadFail m
                  )
               => Version
+              -> Maybe FilePath
               -> Excepts
                    '[ AlreadyInstalled
                     , CopyError
@@ -605,9 +666,9 @@ installHLSBin :: ( MonadMask m
                     ]
                    m
                    ()
-installHLSBin ver = do
+installHLSBin ver isoFilepath = do
   dlinfo <- liftE $ getDownloadInfo HLS ver
-  installHLSBindist dlinfo ver
+  installHLSBindist dlinfo ver isoFilepath
 
 
 -- | Installs stack into @~\/.ghcup\/bin/stack-\<ver\>@ and
@@ -627,6 +688,7 @@ installStackBin :: ( MonadMask m
                    , MonadFail m
                    )
                 => Version
+                -> Maybe FilePath
                 -> Excepts
                      '[ AlreadyInstalled
                       , CopyError
@@ -642,9 +704,9 @@ installStackBin :: ( MonadMask m
                       ]
                      m
                      ()
-installStackBin ver = do
+installStackBin ver isoFilepath = do
   dlinfo <- liftE $ getDownloadInfo Stack ver
-  installStackBindist dlinfo ver
+  installStackBindist dlinfo ver isoFilepath
 
 
 -- | Like 'installStackBin', except takes the 'DownloadInfo' as
@@ -663,6 +725,7 @@ installStackBindist :: ( MonadMask m
                        )
                     => DownloadInfo
                     -> Version
+                    -> Maybe FilePath
                     -> Excepts
                          '[ AlreadyInstalled
                           , CopyError
@@ -678,14 +741,18 @@ installStackBindist :: ( MonadMask m
                           ]
                          m
                          ()
-installStackBindist dlinfo ver = do
+installStackBindist dlinfo ver isoFilepath = do
   lift $ $(logDebug) [i|Requested to install stack version #{ver}|]
 
   PlatformRequest {..} <- lift getPlatformReq
   Dirs {..} <- lift getDirs
 
-  whenM (lift (stackInstalled ver))
-    (throwE $ AlreadyInstalled Stack ver)
+  case isoFilepath of
+    Nothing ->             -- check previous versions in case of regular installs
+      whenM (lift (stackInstalled ver))
+      (throwE $ AlreadyInstalled Stack ver)
+
+    _ -> pure ()           -- don't do shit for isolates
 
   -- download (or use cached version)
   dl <- liftE $ downloadCached dlinfo Nothing
@@ -698,31 +765,37 @@ installStackBindist dlinfo ver = do
   -- the subdir of the archive where we do the work
   workdir <- maybe (pure tmpUnpack) (liftE . intoSubdir tmpUnpack) (view dlSubdir dlinfo)
 
-  liftE $ installStack' workdir binDir
+  case isoFilepath of
+    Just isoDir -> do                 -- isolated install
+      lift $ $(logInfo) [i|isolated installing Stack to #{isoDir}|]
+      liftE $ installStackUnpacked workdir isoDir Nothing
+    Nothing -> do                     -- regular install
+      liftE $ installStackUnpacked workdir binDir (Just ver)
 
-  -- create symlink if this is the latest version
-  sVers <- lift $ fmap rights getInstalledStacks
-  let lInstStack = headMay . reverse . sort $ sVers
-  when (maybe True (ver >=) lInstStack) $ liftE $ setStack ver
-
- where
-  -- | Install an unpacked stack distribution.
-  installStack' :: (MonadLogger m, MonadCatch m, MonadIO m)
-                => FilePath      -- ^ Path to the unpacked stack bindist (where the executable resides)
-                -> FilePath      -- ^ Path to install to
-                -> Excepts '[CopyError] m ()
-  installStack' path inst = do
-    lift $ $(logInfo) "Installing stack"
-    let stackFile = "stack"
-    liftIO $ createDirRecursive' inst
-    let destFileName = stackFile <> "-" <> T.unpack (prettyVer ver) <> exeExt
-    let destPath = inst </> destFileName
-    handleIO (throwE . CopyError . show) $ liftIO $ copyFile
-      (path </> stackFile <> exeExt)
-      destPath
-    lift $ chmod_755 destPath
+      -- create symlink if this is the latest version and a regular install
+      sVers <- lift $ fmap rights getInstalledStacks
+      let lInstStack = headMay . reverse . sort $ sVers
+      when (maybe True (ver >=) lInstStack) $ liftE $ setStack ver
 
 
+-- | Install an unpacked stack distribution.
+installStackUnpacked :: (MonadLogger m, 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
+              -> Excepts '[CopyError] m ()
+installStackUnpacked path inst mver' = do
+  lift $ $(logInfo) "Installing stack"
+  let stackFile = "stack"
+  liftIO $ createDirRecursive' inst
+  let destFileName = stackFile
+                     <> maybe "" (("-" <>) .  T.unpack . prettyVer) mver'
+                     <> exeExt
+  let destPath = inst </> destFileName
+  handleIO (throwE . CopyError . show) $ liftIO $ copyFile
+    (path </> stackFile <> exeExt)
+    destPath
+  lift $ chmod_755 destPath
 
 
     ---------------------
@@ -1704,6 +1777,7 @@ compileGHC :: ( MonadMask m
            -> [Text]                   -- ^ additional args to ./configure
            -> Maybe String             -- ^ build flavour
            -> Bool
+           -> Maybe FilePath           -- ^ isolate dir
            -> Excepts
                 '[ AlreadyInstalled
                  , BuildFailed
@@ -1716,13 +1790,14 @@ compileGHC :: ( MonadMask m
                  , UnknownArchive
                  , TarDirDoesNotExist
                  , NotInstalled
+                 , DirNotEmpty
 #if !defined(TAR)
                  , ArchiveResult
 #endif
                  ]
                 m
                 GHCTargetVersion
-compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour hadrian
+compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour hadrian isolateDir
   = do
     PlatformRequest { .. } <- lift getPlatformReq
     GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
@@ -1792,12 +1867,18 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour had
     alreadyInstalled <- lift $ ghcInstalled installVer
     alreadySet <- fmap (== Just tver) $ lift $ ghcSet (_tvTarget tver)
     when alreadyInstalled $ do
-      lift $ $(logWarn) [i|GHC #{prettyShow tver} already installed. Will overwrite existing version.|]
+      case isolateDir of
+        Just isoDir ->
+          lift $ $(logWarn) [i|GHC #{prettyShow tver} already installed. Isolate installing to #{isoDir} |]
+        Nothing ->
+          lift $ $(logWarn) [i|GHC #{prettyShow tver} already installed. Will overwrite existing version.|]
       lift $ $(logWarn)
         "...waiting for 10 seconds before continuing, you can still abort..."
       liftIO $ threadDelay 10000000 -- give the user a sec to intervene
 
-    ghcdir         <- lift $ ghcupGHCDir installVer
+    ghcdir <- case isolateDir of
+      Just isoDir -> pure isoDir
+      Nothing -> lift $ ghcupGHCDir installVer
 
     bghc <- case bstrap of
       Right g    -> pure $ Right g
@@ -1814,9 +1895,14 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour had
         pure (b, bmk)
       )
 
-    when alreadyInstalled $ do
-      lift $ $(logInfo) [i|Deleting existing installation|]
-      liftE $ rmGHCVer tver
+    case isolateDir of
+      Nothing ->
+        -- only remove old ghc in regular installs
+        when alreadyInstalled $ do
+          lift $ $(logInfo) [i|Deleting existing installation|]
+          liftE $ rmGHCVer tver
+          
+      _ -> pure ()
 
     forM_ mBindist $ \bindist -> do
       liftE $ installPackedGHC bindist
@@ -1825,11 +1911,15 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour had
                                (tver ^. tvVersion)
 
     liftIO $ B.writeFile (ghcdir </> ghcUpSrcBuiltFile) bmk
-
-    reThrowAll GHCupSetError $ postGHCInstall tver
-
-    -- restore
-    when alreadySet $ liftE $ void $ setGHC tver SetGHCOnly
+    
+    case isolateDir of
+      -- set and make symlinks for regular (non-isolated) installs
+      Nothing -> do
+        reThrowAll GHCupSetError $ postGHCInstall tver
+        -- restore
+        when alreadySet $ liftE $ void $ setGHC tver SetGHCOnly
+        
+      _ -> pure ()
 
     pure tver
 
@@ -2037,7 +2127,7 @@ endif|]
         liftIO $ threadDelay 5000000
 
   addBuildFlavourToConf bc = case buildFlavour of
-    Just bf -> [i|BuildFlavour = #{bf}|] <> [s|
+    Just bf -> [i|BuildFlavour = #{bf}
 |] <> [i|#{bc}|]
     Nothing -> bc
 
@@ -2189,6 +2279,7 @@ upgradeGHCup mtarget force' = do
     -------------
 
 
+
 -- | Creates @ghc-x.y.z@ and @ghc-x.y@ symlinks. This is used for
 -- both installing from source and bindist.
 postGHCInstall :: ( MonadReader env m

lib/GHCup/Download.hs

@@ -335,8 +335,8 @@ download uri eDigest dest mfn etags
  where
   scheme = view (uriSchemeL' % schemeBSL') uri
   dl = do
-    let uri' = decUTF8Safe (serializeURIRef' uri)
-    lift $ $(logInfo) [i|downloading: #{uri'}|]
+    destFile <- liftE . reThrowAll @_ @_ @'[DownloadFailed] DownloadFailed $ getDestFile
+    lift $ $(logInfo) [i|downloading: #{uri'} as file #{destFile}|]
 
     -- destination dir must exist
     liftIO $ createDirRecursive' dest
@@ -378,7 +378,7 @@ download uri eDigest dest mfn etags
                             _ -> liftE $ throwE @_ @'[DownloadFailed] (DownloadFailed (toVariantAt @0 (MalformedHeaders headers)
                               :: V '[MalformedHeaders]))
 
-                          writeEtags (parseEtags headers)
+                          writeEtags destFile (parseEtags headers)
                     else
                       liftE $ lEM @_ @'[ProcessError] $ exec "curl" 
                         (o' ++ ["-fL", "-o", destFile, T.unpack uri']) Nothing Nothing
@@ -395,13 +395,13 @@ download uri eDigest dest mfn etags
                         case _exitCode of
                           ExitSuccess -> do
                             liftIO $ copyFile destFileTemp destFile
-                            writeEtags (parseEtags (decUTF8Safe' _stdErr))
+                            writeEtags destFile (parseEtags (decUTF8Safe' _stdErr))
                           ExitFailure i'
                             | i' == 8
                             , Just _ <- find (T.pack "304 Not Modified" `T.isInfixOf`) . T.lines . decUTF8Safe' $ _stdErr
                                      -> do
                                           $logDebug "Not modified, skipping download"
-                                          writeEtags (parseEtags (decUTF8Safe' _stdErr))
+                                          writeEtags destFile (parseEtags (decUTF8Safe' _stdErr))
                             | otherwise -> throwE (NonZeroExit i' "wget" opts)
                       else do
                         let opts = o' ++ ["-O", destFileTemp , T.unpack uri']
@@ -416,10 +416,10 @@ download uri eDigest dest mfn etags
                       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 (pure $ Just etag))
+                        $ catchE @HTTPNotModified @'[DownloadFailed] @'[] (\(HTTPNotModified etag) -> lift $ writeEtags destFile (pure $ Just etag))
                         $ do
                           r <- downloadToFile https host fullPath port destFile addHeaders
-                          writeEtags (pure $ decUTF8Safe <$> getHeader r "etag")
+                          writeEtags destFile (pure $ decUTF8Safe <$> getHeader r "etag")
                     else void $ liftE $ catchE @HTTPNotModified
                                         @'[DownloadFailed]
                                    (\e@(HTTPNotModified _) ->
@@ -432,12 +432,18 @@ download uri eDigest dest mfn etags
 
 
   -- Manage to find a file we can write the body into.
-  destFile :: FilePath
-  destFile = maybe (dest </> T.unpack (decUTF8Safe (urlBaseName path)))
-                  (dest </>)
-                  mfn
+  getDestFile :: Monad m => Excepts '[NoUrlBase] m FilePath
+  getDestFile = 
+    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'
 
   path = view pathL' uri
+  uri' = decUTF8Safe (serializeURIRef' uri)
 
   parseEtags :: (MonadLogger m, MonadIO m, MonadThrow m) => T.Text -> m (Maybe T.Text)
   parseEtags stderr = do
@@ -456,8 +462,8 @@ download uri eDigest dest mfn etags
         $logDebug "No etags header found"
         pure Nothing
 
-  writeEtags :: (MonadLogger m, MonadIO m, MonadThrow m) => m (Maybe T.Text) -> m ()
-  writeEtags getTags = do
+  writeEtags :: (MonadLogger m, MonadIO m, MonadThrow m) => FilePath -> m (Maybe T.Text) -> m ()
+  writeEtags destFile getTags = do
     getTags >>= \case
       Just t -> do
         $logDebug [i|Writing etagsFile #{(etagsFile destFile)}|]

lib/GHCup/Errors.hs

@@ -134,6 +134,13 @@ instance Pretty AlreadyInstalled where
   pPrint (AlreadyInstalled tool ver') =
     text [i|#{tool}-#{prettyShow ver'} is already installed|]
 
+-- | The Directory is supposed to be empty, but wasn't.
+data DirNotEmpty = DirNotEmpty {path :: FilePath}
+
+instance Pretty DirNotEmpty where
+  pPrint (DirNotEmpty path) = do
+    text [i|The directory was expected to be empty, but isn't: #{path}|]
+
 -- | The tool is not installed. Some operations rely on a tool
 -- to be installed (such as setting the current GHC version).
 data NotInstalled = NotInstalled Tool GHCTargetVersion
@@ -168,6 +175,16 @@ instance Pretty FileDoesNotExistError where
   pPrint (FileDoesNotExistError file) =
     text [i|File "#{file}" does not exist.|]
 
+-- | The file already exists
+-- (e.g. when we use isolated installs with the same path).
+-- (e.g. This is done to prevent any overwriting)
+data FileAlreadyExistsError = FileAlreadyExistsError FilePath
+  deriving Show
+
+instance Pretty FileAlreadyExistsError where
+  pPrint (FileAlreadyExistsError file) =
+    text [i|File "#{file}" Already exists.|]
+
 data TarDirDoesNotExist = TarDirDoesNotExist TarDir
   deriving Show
 
@@ -327,6 +344,15 @@ instance Pretty UnexpectedListLength where
 
 instance Exception UnexpectedListLength
 
+data NoUrlBase = NoUrlBase Text
+  deriving Show
+
+instance Pretty NoUrlBase where
+  pPrint (NoUrlBase url) =
+    text [i|Couldn't get a base filename from url #{url}|]
+
+instance Exception NoUrlBase
+
 
 
     ------------------------

lib/GHCup/Types.hs

@@ -304,6 +304,41 @@ data UserSettings = UserSettings
 defaultUserSettings :: UserSettings
 defaultUserSettings = UserSettings Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing
 
+fromSettings :: Settings -> Maybe KeyBindings -> UserSettings
+fromSettings Settings{..} Nothing =
+  UserSettings {
+      uCache = Just cache
+    , uNoVerify = Just noVerify
+    , uVerbose = Just verbose
+    , uKeepDirs = Just keepDirs
+    , uDownloader = Just downloader
+    , uNoNetwork = Just noNetwork
+    , uKeyBindings = Nothing
+    , uUrlSource = Just urlSource
+  }
+fromSettings Settings{..} (Just KeyBindings{..}) =
+  let ukb = UserKeyBindings
+            { kUp           = Just bUp        
+            , kDown         = Just bDown      
+            , kQuit         = Just bQuit      
+            , kInstall      = Just bInstall   
+            , kUninstall    = Just bUninstall 
+            , kSet          = Just bSet       
+            , kChangelog    = Just bChangelog 
+            , kShowAll      = Just bShowAllVersions
+            , kShowAllTools = Just bShowAllTools
+            }
+  in UserSettings {
+      uCache = Just cache
+    , uNoVerify = Just noVerify
+    , uVerbose = Just verbose
+    , uKeepDirs = Just keepDirs
+    , uDownloader = Just downloader
+    , uNoNetwork = Just noNetwork
+    , uKeyBindings = Just ukb
+    , uUrlSource = Just urlSource
+  }
+
 data UserKeyBindings = UserKeyBindings
   { kUp        :: Maybe Key
   , kDown      :: Maybe Key

lib/GHCup/Types/JSON.hs

@@ -316,3 +316,6 @@ deriveJSON defaultOptions { sumEncoding = ObjectWithSingleField } ''URLSource
 deriveJSON defaultOptions { sumEncoding = ObjectWithSingleField } ''Key
 deriveJSON defaultOptions { fieldLabelModifier = \str' -> maybe str' T.unpack . T.stripPrefix (T.pack "k-") . T.pack . kebab $ str' } ''UserKeyBindings
 deriveJSON defaultOptions { fieldLabelModifier = \str' -> maybe str' T.unpack . T.stripPrefix (T.pack "u-") . T.pack . kebab $ str' } ''UserSettings
+
+deriveToJSON defaultOptions { fieldLabelModifier = kebab } ''Settings
+deriveToJSON defaultOptions { fieldLabelModifier = drop 2 . kebab } ''KeyBindings -- move under key-bindings key

www/Matrix_logo.svg

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg version="1.1" viewBox="0 0 75 32" xmlns="http://www.w3.org/2000/svg" xmlns:cc="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
+<title>Matrix (protocol) logo</title>
+ <g fill="#040404">
+  <path d="m0.936 0.732v30.52h2.194v0.732h-3.035v-31.98h3.034v0.732zm8.45 9.675v1.544h0.044a4.461 4.461 0 0 1 1.487-1.368c0.58-0.323 1.245-0.485 1.993-0.485 0.72 0 1.377 0.14 1.972 0.42 0.595 0.279 1.047 0.771 1.355 1.477 0.338-0.5 0.796-0.941 1.377-1.323 0.58-0.383 1.266-0.574 2.06-0.574 0.602 0 1.16 0.074 1.674 0.22 0.514 0.148 0.954 0.383 1.322 0.707 0.366 0.323 0.653 0.746 0.859 1.268 0.205 0.522 0.308 1.15 0.308 1.887v7.633h-3.127v-6.464c0-0.383-0.015-0.743-0.044-1.082a2.305 2.305 0 0 0-0.242-0.882 1.473 1.473 0 0 0-0.584-0.596c-0.257-0.146-0.606-0.22-1.047-0.22-0.44 0-0.796 0.085-1.068 0.253-0.272 0.17-0.485 0.39-0.639 0.662a2.654 2.654 0 0 0-0.308 0.927 7.074 7.074 0 0 0-0.078 1.048v6.354h-3.128v-6.398c0-0.338-7e-3 -0.673-0.021-1.004a2.825 2.825 0 0 0-0.188-0.916 1.411 1.411 0 0 0-0.55-0.673c-0.258-0.168-0.636-0.253-1.135-0.253a2.33 2.33 0 0 0-0.584 0.1 1.94 1.94 0 0 0-0.705 0.374c-0.228 0.184-0.422 0.449-0.584 0.794-0.161 0.346-0.242 0.798-0.242 1.357v6.619h-3.129v-11.41zm16.46 1.677a3.751 3.751 0 0 1 1.233-1.17 5.37 5.37 0 0 1 1.685-0.629 9.579 9.579 0 0 1 1.884-0.187c0.573 0 1.153 0.04 1.74 0.121 0.588 0.081 1.124 0.24 1.609 0.475 0.484 0.235 0.88 0.562 1.19 0.981 0.308 0.42 0.462 0.975 0.462 1.666v5.934c0 0.516 0.03 1.008 0.088 1.478 0.058 0.471 0.161 0.824 0.308 1.06h-3.171a4.435 4.435 0 0 1-0.22-1.104c-0.5 0.515-1.087 0.876-1.762 1.081a7.084 7.084 0 0 1-2.071 0.31c-0.544 0-1.05-0.067-1.52-0.2a3.472 3.472 0 0 1-1.234-0.617 2.87 2.87 0 0 1-0.826-1.059c-0.199-0.426-0.298-0.934-0.298-1.522 0-0.647 0.114-1.18 0.342-1.6 0.227-0.419 0.52-0.753 0.881-1.004 0.36-0.25 0.771-0.437 1.234-0.562 0.462-0.125 0.929-0.224 1.399-0.298 0.47-0.073 0.932-0.132 1.387-0.176 0.456-0.044 0.86-0.11 1.212-0.199 0.353-0.088 0.631-0.217 0.837-0.386s0.301-0.415 0.287-0.74c0-0.337-0.055-0.606-0.166-0.804a1.217 1.217 0 0 0-0.44-0.464 1.737 1.737 0 0 0-0.639-0.22 5.292 5.292 0 0 0-0.782-0.055c-0.617 0-1.101 0.132-1.454 0.397-0.352 0.264-0.558 0.706-0.617 1.323h-3.128c0.044-0.735 0.227-1.345 0.55-1.83zm6.179 4.423a5.095 5.095 0 0 1-0.639 0.165 9.68 9.68 0 0 1-0.716 0.11c-0.25 0.03-0.5 0.067-0.749 0.11a5.616 5.616 0 0 0-0.694 0.177 2.057 2.057 0 0 0-0.594 0.298c-0.17 0.125-0.305 0.284-0.408 0.474-0.103 0.192-0.154 0.434-0.154 0.728 0 0.28 0.051 0.515 0.154 0.706 0.103 0.192 0.242 0.342 0.419 0.453 0.176 0.11 0.381 0.187 0.617 0.231 0.234 0.044 0.477 0.066 0.726 0.066 0.617 0 1.094-0.102 1.432-0.309 0.338-0.205 0.587-0.452 0.75-0.739 0.16-0.286 0.26-0.576 0.297-0.87 0.036-0.295 0.055-0.53 0.055-0.707v-1.17a1.4 1.4 0 0 1-0.496 0.277zm11.86-6.1v2.096h-2.291v5.647c0 0.53 0.088 0.883 0.264 1.059 0.176 0.177 0.529 0.265 1.057 0.265 0.177 0 0.345-7e-3 0.507-0.022 0.161-0.015 0.316-0.037 0.463-0.066v2.426a7.49 7.49 0 0 1-0.882 0.089 21.67 21.67 0 0 1-0.947 0.022c-0.484 0-0.944-0.034-1.377-0.1a3.233 3.233 0 0 1-1.145-0.386 2.04 2.04 0 0 1-0.782-0.816c-0.191-0.353-0.287-0.816-0.287-1.39v-6.728h-1.894v-2.096h1.894v-3.42h3.129v3.42h2.29zm4.471 0v2.118h0.044a3.907 3.907 0 0 1 1.454-1.754 4.213 4.213 0 0 1 1.036-0.497 3.734 3.734 0 0 1 1.145-0.176c0.206 0 0.433 0.037 0.683 0.11v2.912a5.862 5.862 0 0 0-0.528-0.077 5.566 5.566 0 0 0-0.595-0.033c-0.573 0-1.058 0.096-1.454 0.287a2.52 2.52 0 0 0-0.958 0.783 3.143 3.143 0 0 0-0.518 1.158 6.32 6.32 0 0 0-0.154 1.434v5.14h-3.128v-11.4zm5.684-1.765v-2.582h3.128v2.582h-3.127zm3.128 1.765v11.4h-3.127v-11.4h3.128zm1.63 0h3.569l2.005 2.978 1.982-2.978h3.459l-3.745 5.339 4.208 6.067h-3.57l-2.378-3.596-2.38 3.596h-3.502l4.097-6.001zm15.3 20.84v-30.52h-2.194v-0.732h3.035v31.98h-3.035v-0.732z"/>
+ </g>
+</svg>

www/Octicons-bug.svg

@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   height="800.3468"
+   width="733.88495"
+   version="1.1"
+   id="svg4"
+   sodipodi:docname="Octicons-bug.svg"
+   inkscape:version="1.1 (c68e22c387, 2021-05-23)"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg">
+  <defs
+     id="defs8" />
+  <sodipodi:namedview
+     id="namedview6"
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1.0"
+     inkscape:pageshadow="2"
+     inkscape:pageopacity="0.0"
+     inkscape:pagecheckerboard="0"
+     showgrid="false"
+     inkscape:zoom="0.85253906"
+     inkscape:cx="367.1386"
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+     id="path2" />
+</svg>

www/index.html

@@ -138,12 +138,12 @@
       </div>
 
       <p>
-        Need help? Ask on <a href="https://kiwiirc.com/nextclient/irc.libera.chat/#haskell-ghcup">#haskell-ghcup</a>, <a href="https://kiwiirc.com/nextclient/irc.libera.chat/#haskell">#haskell</a> or <a href="https://gitlab.haskell.org/haskell/ghcup-hs/issues">report a bug</a>.
+	  Need help? Ask on <a href="https://kiwiirc.com/nextclient/irc.libera.chat/?nick=Guest%7C?#haskell,#haskell-ghcup"><img src="irc.svg" height="18px" alt="" />IRC</a>, <a href="https://discord.gg/pKYf3zDQU7">Discord</a>, <a href="https://app.element.io/#/room/#matrix:matrix.org"><img src="Matrix_logo.svg" height="25px" alt="" style="top:5px;position:relative;" /></a> or <a href="https://gitlab.haskell.org/haskell/ghcup-hs/issues">report a bug <img src="Octicons-bug.svg" height="18px" alt="" /></a>.
       </p>
 
       <p id="about">
         <img src="haskell-logo.svg" alt="" />
-        ghcup is a haskell.org hosted project.
+        ghcup is a haskell.org supported project.
         <br/>
         <a href="https://www.haskell.org/downloads/">other installation options</a>
         &nbsp;&middot;&nbsp;

www/irc.svg

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+   viewBox="0 0 18 18.043058"
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+   version="1.1"
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+   sodipodi:docname="irc.svg"
+   inkscape:version="1.1 (c68e22c387, 2021-05-23)"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
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+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg">
+  <defs
+     id="defs8" />
+  <sodipodi:namedview
+     id="namedview6"
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1.0"
+     inkscape:pageshadow="2"
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+     class="heroicon-ui"
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