Refactor package imports

Use an (Raw)PkgQual datatype instead of `Maybe FastString` to represent
package imports. Factorize the code that renames RawPkgQual into PkgQual
in function `rnPkgQual`. Renaming consists in checking if the FastString
is the magic "this" keyword, the home-unit unit-id or something else.

Bump haddock submodule

2 files changed, 14 insertions, 10 deletions

diff --git a/ghc/GHCi/UI.hs b/ghc/GHCi/UI.hs
index 4a82a51e84..fc19207cc2 100644
--- a/ghc/GHCi/UI.hs
+++ b/ghc/GHCi/UI.hs
@@ -69,7 +69,6 @@ import GHC.Types.TyThing.Ppr
 import GHC.Core.TyCo.Ppr
 import GHC.Types.SafeHaskell ( getSafeMode )
 import GHC.Types.Name
-import GHC.Types.SourceText
 import GHC.Types.Var ( varType )
 import GHC.Iface.Syntax ( showToHeader )
 import GHC.Builtin.Names
@@ -78,6 +77,7 @@ import GHC.Types.Name.Reader as RdrName ( getGRE_NameQualifier_maybes, getRdrNam
 import GHC.Types.SrcLoc as SrcLoc
 import qualified GHC.Parser.Lexer as Lexer
 import GHC.Parser.Header ( toArgs )
+import GHC.Types.PkgQual
 
 import GHC.Unit
 import GHC.Unit.Finder as Finder
@@ -2049,7 +2049,7 @@ addModule files = do
       let dflags    = hsc_dflags hsc_env
       let fopts     = initFinderOpts dflags
       result <- liftIO $
-        Finder.findImportedModule fc fopts units home_unit m (Just (fsLit "this"))
+        Finder.findImportedModule fc fopts units home_unit m (ThisPkg (homeUnitId home_unit))
       case result of
         Found _ _ -> return True
         _ -> (liftIO $ putStrLn $
@@ -2208,7 +2208,8 @@ keepPackageImports = filterM is_pkg_import
      is_pkg_import :: GHC.GhcMonad m => InteractiveImport -> m Bool
      is_pkg_import (IIModule _) = return False
      is_pkg_import (IIDecl d)
-         = do e <- MC.try $ GHC.findModule mod_name (fmap sl_fs $ ideclPkgQual d)
+         = do pkgqual <- GHC.renameRawPkgQualM (ideclPkgQual d)
+              e <- MC.try $ GHC.findQualifiedModule pkgqual mod_name
               case e :: Either SomeException Module of
                 Left _  -> return False
                 Right m -> return (not (isMainUnitModule m))
@@ -2216,6 +2217,7 @@ keepPackageImports = filterM is_pkg_import
           mod_name = unLoc (ideclName d)
 
 
+
 modulesLoadedMsg :: GHC.GhcMonad m => SuccessFlag -> [GHC.ModSummary] -> m ()
 modulesLoadedMsg ok mods = do
   dflags <- getDynFlags
@@ -2560,9 +2562,10 @@ guessCurrentModule cmd
        when (null imports) $ throwGhcException $
           CmdLineError (':' : cmd ++ ": no current module")
        case (head imports) of
-          IIModule m -> GHC.findModule m Nothing
-          IIDecl d   -> GHC.findModule (unLoc (ideclName d))
-                                       (fmap sl_fs $ ideclPkgQual d)
+          IIModule m -> GHC.findQualifiedModule NoPkgQual m
+          IIDecl d   -> do
+            pkgqual <- GHC.renameRawPkgQualM (ideclPkgQual d)
+            GHC.findQualifiedModule pkgqual (unLoc (ideclName d))
 
 -- without bang, show items in context of their parents and omit children
 -- with bang, show class methods and data constructors separately, and
@@ -2759,8 +2762,8 @@ checkAdd ii = do
 
     IIDecl d -> do
        let modname = unLoc (ideclName d)
-           pkgqual = ideclPkgQual d
-       m <- GHC.lookupModule modname (fmap sl_fs pkgqual)
+       pkgqual <- GHC.renameRawPkgQualM (ideclPkgQual d)
+       m <- GHC.lookupQualifiedModule pkgqual modname
        when safe $ do
            t <- GHC.isModuleTrusted m
            when (not t) $ throwGhcException $ ProgramError $ ""
@@ -4510,7 +4513,7 @@ lookupModule :: GHC.GhcMonad m => String -> m Module
 lookupModule mName = lookupModuleName (GHC.mkModuleName mName)
 
 lookupModuleName :: GHC.GhcMonad m => ModuleName -> m Module
-lookupModuleName mName = GHC.lookupModule mName Nothing
+lookupModuleName mName = GHC.lookupQualifiedModule NoPkgQual mName
 
 isMainUnitModule :: Module -> Bool
 isMainUnitModule m = GHC.moduleUnit m == mainUnit
diff --git a/ghc/Main.hs b/ghc/Main.hs
index b1c45e9cc4..5e6042173f 100644
--- a/ghc/Main.hs
+++ b/ghc/Main.hs
@@ -53,6 +53,7 @@ import GHC.Types.Basic     ( failed )
 import GHC.Types.SrcLoc
 import GHC.Types.SourceError
 import GHC.Types.Unique.Supply
+import GHC.Types.PkgQual
 
 import GHC.Utils.Error
 import GHC.Utils.Misc
@@ -881,7 +882,7 @@ abiHash strs = do
 
   let find_it str = do
          let modname = mkModuleName str
-         r <- findImportedModule fc fopts units home_unit modname Nothing
+         r <- findImportedModule fc fopts units home_unit modname NoPkgQual
          case r of
            Found _ m -> return m
            _error    -> throwGhcException $ CmdLineError $ showSDoc dflags $