re-implement function-argument docs

..on top of the lexParseRn work.
This patch doesn't change the InstalledInterface format, and thus,
it does not work cross-package, but that will be easy to add
subsequently.

4 files changed, 98 insertions, 22 deletions

diff --git a/src/Haddock/Interface/AttachInstances.hs b/src/Haddock/Interface/AttachInstances.hs
index f9a951f3..122ea5d0 100644
--- a/src/Haddock/Interface/AttachInstances.hs
+++ b/src/Haddock/Interface/AttachInstances.hs
@@ -44,13 +44,14 @@ attachInstances = mapM attach
     attach iface = do
       newItems <- mapM attachExport $ ifaceExportItems iface
       return $ iface { ifaceExportItems = newItems }
-    attachExport (ExportDecl decl@(L _ (TyClD d)) doc subs _) = do
+    attachExport export@ExportDecl{expItemDecl = L _ (TyClD d)} = do
        mb_info <- getAllInfo (unLoc (tcdLName d))
-       return $ ExportDecl decl doc subs $ case mb_info of
+       return $ export { expItemInstances = case mb_info of
          Just (_, _, instances) ->
            map toHsInstHead . sortImage instHead . map instanceHead $ instances
          Nothing ->
            []
+        }
     attachExport export = return export
 
 
diff --git a/src/Haddock/Interface/Create.hs b/src/Haddock/Interface/Create.hs
index 29391702..d919ab4b 100644
--- a/src/Haddock/Interface/Create.hs
+++ b/src/Haddock/Interface/Create.hs
@@ -19,6 +19,7 @@ import Haddock.GhcUtils
 import Haddock.Utils
 import Haddock.Convert
 import Haddock.Interface.LexParseRn
+import Haddock.Interface.ExtractFnArgDocs
 
 import qualified Data.Map as Map
 import Data.Map (Map)
@@ -26,6 +27,7 @@ import Data.List
 import Data.Maybe
 import Data.Ord
 import Control.Monad
+import qualified Data.Traversable as Traversable
 
 import GHC hiding (flags)
 import Name
@@ -151,34 +153,46 @@ declInfos gre decls =
   forM decls $ \(parent@(L _ d), mbDocString) -> do
             mbDoc <- lexParseRnHaddockCommentList NormalHaddockComment
                        gre mbDocString
+            fnArgsDoc <- fmap (Map.mapMaybe id) $
+                Traversable.forM (getDeclFnArgDocs d) $
+                \doc -> lexParseRnHaddockComment NormalHaddockComment gre doc
 
-            let subsStringy = subordinates d
-            subs <- forM subsStringy $ \(subName, mbSubDocString) -> do
+            let subs_ = subordinates d
+            subs <- forM subs_ $ \(subName, mbSubDocStr, subFnArgsDocStr) -> do
                 mbSubDoc <- lexParseRnHaddockCommentList NormalHaddockComment
-                              gre mbSubDocString
-                return (subName, mbSubDoc)
+                              gre mbSubDocStr
+                subFnArgsDoc <- fmap (Map.mapMaybe id) $
+                  Traversable.forM subFnArgsDocStr $
+                  \doc -> lexParseRnHaddockComment NormalHaddockComment gre doc
+                return (subName, (mbSubDoc, subFnArgsDoc))
 
-            return (parent, mbDoc, subs)
+            return (parent, (mbDoc, fnArgsDoc), subs)
 
 
-subordinates :: HsDecl Name -> [(Name, MaybeDocStrings)]
+subordinates :: HsDecl Name -> [(Name, MaybeDocStrings, Map Int HsDocString)]
 subordinates (TyClD d) = classDataSubs d
 subordinates _ = []
 
 
-classDataSubs :: TyClDecl Name -> [(Name, MaybeDocStrings)]
+classDataSubs :: TyClDecl Name -> [(Name, MaybeDocStrings, Map Int HsDocString)]
 classDataSubs decl
   | isClassDecl decl = classSubs
   | isDataDecl  decl = dataSubs
   | otherwise        = []
   where
-    classSubs = [ (declName d, doc) | (L _ d, doc) <- classDecls decl ]
+    classSubs = [ (declName d, doc, fnArgsDoc)
+                | (L _ d, doc) <- classDecls decl
+                , let fnArgsDoc = getDeclFnArgDocs d ]
     dataSubs  = constrs ++ fields   
       where
         cons    = map unL $ tcdCons decl
-        constrs = [ (unL $ con_name c, maybeToList $ fmap unL $ con_doc c)
+        -- should we use the type-signature of the constructor
+        -- and the docs of the fields to produce fnArgsDoc for the constr,
+        -- just in case someone exports it without exporting the type
+        -- and perhaps makes it look like a function?  I doubt it.
+        constrs = [ (unL $ con_name c, maybeToList $ fmap unL $ con_doc c, Map.empty)
                   | c <- cons ]
-        fields  = [ (unL n, maybeToList $ fmap unL doc)
+        fields  = [ (unL n, maybeToList $ fmap unL doc, Map.empty)
                   | RecCon flds <- map con_details cons
                   , ConDeclField n _ doc <- flds ]
 
@@ -495,12 +509,12 @@ mkExportItems modMap this_mod gre exported_names decls declMap
                    let hsdecl = tyThingToHsSynSig tyThing
                    return [ mkExportDecl t
                      ( hsdecl
-                     , fmap (fmapHsDoc getName) $
-                         Map.lookup t (instDocMap iface)
+                     , (fmap (fmapHsDoc getName) $
+                         Map.lookup t (instDocMap iface), Map.empty{-todo-})
                      , map (\subt ->
                               ( subt
-                              , fmap (fmapHsDoc getName) $
-                                    Map.lookup subt (instDocMap iface)
+                              , (fmap (fmapHsDoc getName) $
+                                    Map.lookup subt (instDocMap iface), Map.empty{-todo-})
                               )
                            )
                            subs
@@ -637,7 +651,7 @@ extractRecSel nm mdl t tvs (L _ con : rest) =
 -- Pruning
 pruneExportItems :: [ExportItem Name] -> [ExportItem Name]
 pruneExportItems items = filter hasDoc items
-  where hasDoc (ExportDecl _ d _ _) = isJust d
+  where hasDoc (ExportDecl{expItemMbDoc = (d, _)}) = isJust d
 	hasDoc _ = True
 
 
diff --git a/src/Haddock/Interface/ExtractFnArgDocs.hs b/src/Haddock/Interface/ExtractFnArgDocs.hs
new file mode 100644
index 00000000..c5198598
--- /dev/null
+++ b/src/Haddock/Interface/ExtractFnArgDocs.hs
@@ -0,0 +1,50 @@
+{-# LANGUAGE PatternGuards #-}
+-----------------------------------------------------------------------------
+-- |
+-- Module      :  Haddock.Interface.ExtractFnArgDocs
+-- Copyright   :  (c) Isaac Dupree 2009,
+-- License     :  BSD-like
+--
+-- Maintainer  :  haddock@projects.haskell.org
+-- Stability   :  experimental
+-- Portability :  portable
+-----------------------------------------------------------------------------
+
+module Haddock.Interface.ExtractFnArgDocs (
+  getDeclFnArgDocs, getSigFnArgDocs, getTypeFnArgDocs
+) where
+
+import Haddock.Types
+
+import qualified Data.Map as Map
+import Data.Map (Map)
+
+import GHC
+
+-- the type of Name doesn't matter, except in 6.10 where
+-- HsDocString = HsDoc Name, so we can't just say "HsDecl name" yet.
+
+getDeclFnArgDocs :: HsDecl Name -> Map Int HsDocString
+getDeclFnArgDocs (SigD (TypeSig _ ty)) = getTypeFnArgDocs ty
+getDeclFnArgDocs (ForD (ForeignImport _ ty _)) = getTypeFnArgDocs ty
+getDeclFnArgDocs _ = Map.empty
+
+getSigFnArgDocs :: Sig Name -> Map Int HsDocString
+getSigFnArgDocs (TypeSig _ ty) = getTypeFnArgDocs ty
+getSigFnArgDocs _ = Map.empty
+
+getTypeFnArgDocs :: LHsType Name -> Map Int HsDocString
+getTypeFnArgDocs ty = getLTypeDocs 0 ty
+
+
+getLTypeDocs :: Int -> LHsType Name -> Map Int HsDocString
+getLTypeDocs n (L _ ty) = getTypeDocs n ty
+
+getTypeDocs :: Int -> HsType Name -> Map Int HsDocString
+getTypeDocs n (HsForAllTy _ _ _ ty) = getLTypeDocs n ty
+getTypeDocs n (HsFunTy (L _ (HsDocTy _arg_type (L _ doc))) res_type) =
+      Map.insert n doc $ getLTypeDocs (n+1) res_type
+getTypeDocs n (HsFunTy _ res_type) = getLTypeDocs (n+1) res_type
+getTypeDocs n (HsDocTy _res_type (L _ doc)) = Map.singleton n doc
+getTypeDocs _ _res_type = Map.empty
+
diff --git a/src/Haddock/Interface/Rename.hs b/src/Haddock/Interface/Rename.hs
index b377b4fb..0caf79ba 100644
--- a/src/Haddock/Interface/Rename.hs
+++ b/src/Haddock/Interface/Rename.hs
@@ -38,8 +38,8 @@ renameInterface renamingEnv warnings iface =
         where fn env name = Map.insert name (ifaceMod iface) env
 
       docMap = Map.map (\(_,x,_) -> x) (ifaceDeclMap iface)
-      docs   = [ (n, doc) | (n, Just doc) <- Map.toList docMap ]
-      renameMapElem (k,d) = do d' <- renameDoc d; return (k, d')
+      docs   = Map.toList docMap
+      renameMapElem (k,d) = do d' <- renameDocForDecl d; return (k, d')
 
       -- rename names in the exported declarations to point to things that
       -- are closer to, or maybe even exported by, the current module.
@@ -141,6 +141,13 @@ renameExportItems :: [ExportItem Name] -> RnM [ExportItem DocName]
 renameExportItems = mapM renameExportItem
 
 
+renameDocForDecl :: (Maybe (HsDoc Name), FnArgsDoc Name) -> RnM (Maybe (HsDoc DocName), FnArgsDoc DocName)
+renameDocForDecl (mbDoc, fnArgsDoc) = do
+  mbDoc' <- renameMaybeDoc mbDoc
+  fnArgsDoc' <- renameFnArgsDoc fnArgsDoc
+  return (mbDoc', fnArgsDoc')
+
+
 renameMaybeDoc :: Maybe (HsDoc Name) -> RnM (Maybe (HsDoc DocName))
 renameMaybeDoc = mapM renameDoc
 
@@ -199,6 +206,10 @@ renameDoc d = case d of
   DocAName str -> return (DocAName str)
 
 
+renameFnArgsDoc :: FnArgsDoc Name -> RnM (FnArgsDoc DocName)
+renameFnArgsDoc = mapM renameDoc
+
+
 renameLPred :: LHsPred Name -> RnM (LHsPred DocName)
 renameLPred = mapM renamePred
 
@@ -434,7 +445,7 @@ renameExportItem item = case item of
     return (ExportGroup lev id_ doc')
   ExportDecl decl doc subs instances -> do
     decl' <- renameLDecl decl
-    doc'  <- mapM renameDoc doc
+    doc'  <- renameDocForDecl doc
     subs' <- mapM renameSub subs
     instances' <- mapM renameInstHead instances
     return (ExportDecl decl' doc' subs' instances')
@@ -447,8 +458,8 @@ renameExportItem item = case item of
     return (ExportDoc doc')
 
 
-renameSub :: (Name, Maybe (HsDoc Name)) -> RnM (DocName, Maybe (HsDoc DocName))
+renameSub :: (Name, DocForDecl Name) -> RnM (DocName, DocForDecl DocName)
 renameSub (n,doc) = do
   n' <- rename n
-  doc' <- mapM renameDoc doc
+  doc' <- renameDocForDecl doc
   return (n', doc')