Generate docs for orphan instances

7 files changed, 76 insertions, 21 deletions

diff --git a/haddock-api/src/Haddock/Backends/Xhtml.hs b/haddock-api/src/Haddock/Backends/Xhtml.hs
index e5e4db3f..fce95814 100644
--- a/haddock-api/src/Haddock/Backends/Xhtml.hs
+++ b/haddock-api/src/Haddock/Backends/Xhtml.hs
@@ -525,7 +525,7 @@ ifaceToHtml maybe_source_url maybe_wiki_url iface unicode qual
   = ppModuleContents qual exports +++
     description +++
     synopsis +++
-    divInterface (maybe_doc_hdr +++ bdy)
+    divInterface (maybe_doc_hdr +++ bdy +++ orphans)
   where
     exports = numberSectionHeadings (ifaceRnExportItems iface)
 
@@ -564,6 +564,9 @@ ifaceToHtml maybe_source_url maybe_wiki_url iface unicode qual
       foldr (+++) noHtml $
         mapMaybe (processExport False linksInfo unicode qual) exports
 
+    orphans = (h1 << "Orphan instances") +++
+      ppOrphanInstances linksInfo (ifaceRnOrphanInstances iface) False unicode qual
+
     linksInfo = (maybe_source_url, maybe_wiki_url)
 
 
diff --git a/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs b/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs
index e536ae4b..031b40e5 100644
--- a/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs
+++ b/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs
@@ -16,7 +16,7 @@
 module Haddock.Backends.Xhtml.Decl (
   ppDecl,
 
-  ppTyName, ppTyFamHeader, ppTypeApp,
+  ppTyName, ppTyFamHeader, ppTypeApp, ppOrphanInstances,
   tyvarNames
 ) where
 
@@ -548,6 +548,21 @@ ppInstances links origin instances splice unicode qual
         ((ppInstHead links splice unicode qual mdoc origin no inst), loc)
 
 
+ppOrphanInstances :: LinksInfo
+                  -> [DocInstance DocName]
+                  -> Splice -> Unicode -> Qualification
+                  -> Html
+ppOrphanInstances links instances splice unicode qual
+  = subOrphanInstances qual links True (zipWith instDecl [1..] instances)
+  where
+    instOrigin :: InstHead name -> InstOrigin name
+    instOrigin inst = OriginClass (ihdClsName inst)
+
+    instDecl :: Int -> DocInstance DocName -> (SubDecl,Located DocName)
+    instDecl no (inst, mdoc, loc) =
+        ((ppInstHead links splice unicode qual mdoc (instOrigin inst) no inst), loc)
+
+
 ppInstHead :: LinksInfo -> Splice -> Unicode -> Qualification
            -> Maybe (MDoc DocName)
            -> InstOrigin DocName -> Int -> InstHead DocName
diff --git a/haddock-api/src/Haddock/Backends/Xhtml/Layout.hs b/haddock-api/src/Haddock/Backends/Xhtml/Layout.hs
index d624a1d0..b20cd172 100644
--- a/haddock-api/src/Haddock/Backends/Xhtml/Layout.hs
+++ b/haddock-api/src/Haddock/Backends/Xhtml/Layout.hs
@@ -31,7 +31,7 @@ module Haddock.Backends.Xhtml.Layout (
   subConstructors,
   subEquations,
   subFields,
-  subInstances, subInstHead, subInstDetails,
+  subInstances, subOrphanInstances, subInstHead, subInstDetails,
   subMethods,
   subMinimal,
 
@@ -200,7 +200,16 @@ subInstances qual nm lnks splice = maybe noHtml wrap . instTable
     subCaption = paragraph ! collapseControl id_ True "caption" << "Instances"
     id_ = makeAnchorId $ "i:" ++ nm
 
- 
+
+subOrphanInstances :: Qualification
+                   -> LinksInfo -> Bool
+                   -> [(SubDecl,Located DocName)] -> Html
+subOrphanInstances qual lnks splice  = maybe noHtml id . instTable
+  where
+    instTable = fmap (thediv ! collapseSection id_ True [] <<) . subTableSrc qual lnks splice
+    id_ = makeAnchorId $ "orphans"
+
+
 subInstHead :: String -- ^ Instance unique id (for anchor generation)
             -> Html -- ^ Header content (instance name and type)
             -> Html
diff --git a/haddock-api/src/Haddock/Interface/AttachInstances.hs b/haddock-api/src/Haddock/Interface/AttachInstances.hs
index e2fd24ee..c3e1275e 100644
--- a/haddock-api/src/Haddock/Interface/AttachInstances.hs
+++ b/haddock-api/src/Haddock/Interface/AttachInstances.hs
@@ -61,7 +61,28 @@ attachInstances expInfo ifaces instIfaceMap = mapM attach ifaces
     attach iface = do
       newItems <- mapM (attachToExportItem expInfo iface ifaceMap instIfaceMap)
                        (ifaceExportItems iface)
-      return $ iface { ifaceExportItems = newItems }
+      let orphanInstances = attachOrphanInstances expInfo iface ifaceMap instIfaceMap (ifaceInstances iface)
+      return $ iface { ifaceExportItems = newItems
+                     , ifaceOrphanInstances = orphanInstances
+                     }
+
+spanName :: NamedThing a => a -> InstHead e -> GenLocated SrcSpan e -> GenLocated SrcSpan e
+spanName s (InstHead { ihdClsName = clsn }) (L instL instn) =
+    let s1 = getSrcSpan s
+        sn = if srcSpanFileName_maybe s1 == srcSpanFileName_maybe instL
+                then instn
+                else clsn
+    in L (getSrcSpan s) sn
+
+attachOrphanInstances :: ExportInfo -> Interface -> IfaceMap -> InstIfaceMap -> [ClsInst] -> [DocInstance Name]
+attachOrphanInstances expInfo iface ifaceMap instIfaceMap cls_instances =
+  [ (synifyInstHead i, instLookup instDocMap n iface ifaceMap instIfaceMap, spanName n (synifyInstHead i) (L noSrcSpan n))
+  | let is = [ (instanceHead' i, getName i) | i <- cls_instances, isOrphan (is_orphan i) ]
+  , (i@(_,_,cls,tys), n) <- sortBy (comparing $ first instHead) is
+  , not $ isInstanceHidden expInfo cls tys
+  ]
+  where
+    -- spanName: attach the location to the name that is the same file as the instance location
 
 
 attachToExportItem :: ExportInfo -> Interface -> IfaceMap -> InstIfaceMap
@@ -107,13 +128,7 @@ attachToExportItem expInfo iface ifaceMap instIfaceMap export =
       ] }
 
     attachFixities e = e
-    -- spanName: attach the location to the name that is the same file as the instance location
-    spanName s (InstHead { ihdClsName = clsn }) (L instL instn) =
-        let s1 = getSrcSpan s
-            sn = if srcSpanFileName_maybe s1 == srcSpanFileName_maybe instL
-                    then instn
-                    else clsn
-        in L (getSrcSpan s) sn
+
     -- spanName on Either
     spanNameE s (Left e) _ =  L (getSrcSpan s) (Left e)
     spanNameE s (Right ok) linst =
diff --git a/haddock-api/src/Haddock/Interface/Create.hs b/haddock-api/src/Haddock/Interface/Create.hs
index 0599151e..e158fb21 100644
--- a/haddock-api/src/Haddock/Interface/Create.hs
+++ b/haddock-api/src/Haddock/Interface/Create.hs
@@ -148,6 +148,8 @@ createInterface tm flags modMap instIfaceMap = do
   , ifaceModuleAliases   = aliases
   , ifaceInstances       = instances
   , ifaceFamInstances    = fam_instances
+  , ifaceOrphanInstances   = [] -- Filled in `attachInstances`
+  , ifaceRnOrphanInstances = [] -- Filled in `renameInterface`
   , ifaceHaddockCoverage = coverage
   , ifaceWarningMap      = warningMap
   , ifaceTokenizedSrc    = tokenizedSrc
diff --git a/haddock-api/src/Haddock/Interface/Rename.hs b/haddock-api/src/Haddock/Interface/Rename.hs
index 146a7c0b..dde8128d 100644
--- a/haddock-api/src/Haddock/Interface/Rename.hs
+++ b/haddock-api/src/Haddock/Interface/Rename.hs
@@ -47,13 +47,16 @@ renameInterface dflags renamingEnv warnings iface =
 
       (rnArgMap, missingNames3) = runRnFM localEnv (mapM (mapM renameDoc) (ifaceArgMap iface))
 
-      (finalModuleDoc, missingNames4)
+      (renamedOrphanInstances, missingNames4)
+        = runRnFM localEnv (mapM renameDocInstance (ifaceOrphanInstances iface))
+
+      (finalModuleDoc, missingNames5)
         = runRnFM localEnv (renameDocumentation (ifaceDoc iface))
 
       -- combine the missing names and filter out the built-ins, which would
-      -- otherwise allways be missing.
+      -- otherwise always be missing.
       missingNames = nub $ filter isExternalName  -- XXX: isExternalName filters out too much
-                    (missingNames1 ++ missingNames2 ++ missingNames3 ++ missingNames4)
+                    (missingNames1 ++ missingNames2 ++ missingNames3 ++ missingNames4 ++ missingNames5)
 
       -- filter out certain built in type constructors using their string
       -- representation. TODO: use the Name constants from the GHC API.
@@ -72,7 +75,8 @@ renameInterface dflags renamingEnv warnings iface =
     return $ iface { ifaceRnDoc         = finalModuleDoc,
                      ifaceRnDocMap      = rnDocMap,
                      ifaceRnArgMap      = rnArgMap,
-                     ifaceRnExportItems = renamedExportItems }
+                     ifaceRnExportItems = renamedExportItems,
+                     ifaceRnOrphanInstances = renamedOrphanInstances}
 
 
 --------------------------------------------------------------------------------
@@ -504,6 +508,13 @@ renameDataFamInstD (DataFamInstDecl { dfid_tycon = tc, dfid_pats = pats_w_bndrs,
                                        = HsWB pats' PlaceHolder PlaceHolder PlaceHolder
                                  , dfid_defn = defn', dfid_fvs = placeHolderNames }) }
 
+renameDocInstance :: DocInstance Name -> RnM (DocInstance DocName)
+renameDocInstance (inst, idoc, L l n) = do
+  inst' <- renameInstHead inst
+  n' <- rename n
+  idoc' <- mapM renameDoc idoc
+  return (inst', idoc',L l n')
+
 renameExportItem :: ExportItem Name -> RnM (ExportItem DocName)
 renameExportItem item = case item of
   ExportModule mdl -> return (ExportModule mdl)
@@ -514,11 +525,7 @@ renameExportItem item = case item of
     decl' <- renameLDecl decl
     doc'  <- renameDocForDecl doc
     subs' <- mapM renameSub subs
-    instances' <- forM instances $ \(inst, idoc, L l n) -> do
-      inst' <- renameInstHead inst
-      n' <- rename n
-      idoc' <- mapM renameDoc idoc
-      return (inst', idoc',L l n')
+    instances' <- forM instances renameDocInstance
     fixities' <- forM fixities $ \(name, fixity) -> do
       name' <- lookupRn name
       return (name', fixity)
diff --git a/haddock-api/src/Haddock/Types.hs b/haddock-api/src/Haddock/Types.hs
index 106d3544..c6631671 100644
--- a/haddock-api/src/Haddock/Types.hs
+++ b/haddock-api/src/Haddock/Types.hs
@@ -124,6 +124,10 @@ data Interface = Interface
   , ifaceInstances       :: ![ClsInst]
   , ifaceFamInstances    :: ![FamInst]
 
+    -- | Orphan instances
+  , ifaceOrphanInstances :: ![DocInstance Name]
+  , ifaceRnOrphanInstances :: ![DocInstance DocName]
+
     -- | The number of haddockable and haddocked items in the module, as a
     -- tuple. Haddockable items are the exports and the module itself.
   , ifaceHaddockCoverage :: !(Int, Int)