Remove Internal SetupMethod

This SetupMethod is no longer used; it is replaced by the InLibrary
SetupMethod which directly calls Cabal library functions instead of
going through defaultMain.

cabal-install/src/Distribution/Client/SetupWrapper.hs

@@ -47,7 +47,6 @@ import Prelude ()
 
 import qualified Distribution.Backpack as Backpack
 import Distribution.CabalSpecVersion (cabalSpecMinimumLibraryVersion)
-import qualified Distribution.Make as Make
 import Distribution.Package
   ( ComponentId
   , PackageId
@@ -65,7 +64,6 @@ import Distribution.PackageDescription
   , buildType
   , specVersion
   )
-import qualified Distribution.Simple as Simple
 import Distribution.Simple.Build.Macros
   ( generatePackageVersionMacros
   )
@@ -121,9 +119,6 @@ import Distribution.Client.Utils
   , makeRelativeToDirS
   , moreRecentFile
   , tryCanonicalizePath
-  , withEnv
-  , withEnvOverrides
-  , withExtraPathEnv
   )
 #ifdef mingw32_HOST_OS
 import Distribution.Client.Utils
@@ -285,8 +280,6 @@ data ASetup = forall kind. ASetup ( Setup kind )
 
 -- | @SetupMethod@ represents one of the methods used to run Cabal commands.
 data SetupMethod (kind :: SetupKind) where
-  -- | run Cabal commands through @cabal@ in the current process
-    InternalMethod :: SetupMethod GeneralSetup
   -- | Directly use Cabal library functions, bypassing the Setup
   -- mechanism entirely.
     LibraryMethod :: SetupMethod InLibrary
@@ -511,7 +504,6 @@ withSetupMethod verbosity options pkg buildType' allowInLibrary with
       with <$> getExternalSetupMethod verbosity options pkg buildType'
 
 runSetupMethod :: WithCallStack (SetupMethod GeneralSetup -> SetupRunner UseGeneralSetup)
-runSetupMethod InternalMethod = internalSetupMethod
 runSetupMethod (ExternalMethod path) = externalSetupMethod path
 runSetupMethod SelfExecMethod = selfExecSetupMethod
 
@@ -696,46 +688,15 @@ setupWrapper verbosity options mpkg cmd getCommonFlags getFlags getExtraArgs wra
                     SRegisterPhase -> InLibrary.register flags lbi extraArgs
         NotInLibrary ->
           error "internal error: NotInLibrary argument but getSetup chose InLibrary"
-    InternalMethod -> notInLibraryMethod
     ExternalMethod {} -> notInLibraryMethod
     SelfExecMethod -> notInLibraryMethod
 
 -- ------------------------------------------------------------
 
--- * Internal SetupMethod
+-- * 'invoke' function
 
 -- ------------------------------------------------------------
 
--- | Run a Setup script by directly invoking the @Cabal@ library.
-internalSetupMethod :: SetupRunner UseGeneralSetup
-internalSetupMethod verbosity options bt args NotInLibrary = do
-  info verbosity $
-    "Using internal setup method with build-type "
-      ++ show bt
-      ++ " and args:\n  "
-      ++ show args
-  -- NB: we do not set the working directory of the process here, because
-  -- we will instead pass the -working-dir flag when invoking the Setup script.
-  -- Note that the Setup script is guaranteed to support this flag, because
-  -- the logic in 'withSetupMethod' guarantees we have an up-to-date Cabal version.
-  --
-  -- In the future, it would be desirable to also stop relying on the following
-  -- pieces of process-global state, as this would allow us to use this internal
-  -- setup method in concurrent contexts.
-  withEnv "HASKELL_DIST_DIR" (getSymbolicPath $ useDistPref options) $
-    withExtraPathEnv (useExtraPathEnv options) $
-      withEnvOverrides (useExtraEnvOverrides options) $
-        buildTypeAction bt args
-
-buildTypeAction :: BuildType -> ([String] -> IO ())
-buildTypeAction Simple = Simple.defaultMainArgs
-buildTypeAction Configure =
-  Simple.defaultMainWithSetupHooksArgs
-    Simple.autoconfSetupHooks
-buildTypeAction Make = Make.defaultMainArgs
-buildTypeAction Hooks  = error "buildTypeAction Hooks"
-buildTypeAction Custom = error "buildTypeAction Custom"
-
 invoke :: Verbosity -> FilePath -> [String] -> SetupScriptOptions -> IO ()
 invoke verbosity path args options = do
   info verbosity $ unwords (path : args)