Hide RHS of TFs with non-exported right hand sides

Not sure what to do about data families yet, since technically it would
not make a lot of sense to display constructors that cannot be used by
the user.

8 files changed, 105 insertions, 44 deletions

diff --git a/html-test/ref/TypeFamilies2.html b/html-test/ref/TypeFamilies2.html
index 102ebd98..ea982f28 100644
--- a/html-test/ref/TypeFamilies2.html
+++ b/html-test/ref/TypeFamilies2.html
@@ -41,6 +41,30 @@ window.onload = function () {pageLoad();setSynopsis("mini_TypeFamilies2.html");}
 	><p class="caption"
 	>TypeFamilies2</p
 	></div
+      ><div id="synopsis"
+      ><p id="control.syn" class="caption expander" onclick="toggleSection('syn')"
+	>Synopsis</p
+	><ul id="section.syn" class="hide" onclick="toggleSection('syn')"
+	><li class="src short"
+	  ><span class="keyword"
+	    >data</span
+	    > <a href="#t:W"
+	    >W</a
+	    ></li
+	  ><li class="src short"
+	  ><span class="keyword"
+	    >type family</span
+	    > <a href="#t:Foo"
+	    >Foo</a
+	    > a</li
+	  ><li class="src short"
+	  ><span class="keyword"
+	    >data family</span
+	    > <a href="#t:Bar"
+	    >Bar</a
+	    > a</li
+	  ></ul
+	></div
       ><div id="interface"
       ><h1
 	>Documentation</h1
@@ -48,13 +72,17 @@ window.onload = function () {pageLoad();setSynopsis("mini_TypeFamilies2.html");}
 	><p class="src"
 	  ><span class="keyword"
 	    >data</span
-	    > <a name="t:X" class="def"
-	    >X</a
+	    > <a name="t:W" class="def"
+	    >W</a
 	    ></p
+	  ><div class="doc"
+	  ><p
+	    >Exported type</p
+	    ></div
 	  ><div class="subs instances"
-	  ><p id="control.i:X" class="caption collapser" onclick="toggleSection('i:X')"
+	  ><p id="control.i:W" class="caption collapser" onclick="toggleSection('i:W')"
 	    >Instances</p
-	    ><div id="section.i:X" class="show"
+	    ><div id="section.i:W" class="show"
 	    ><table
 	      ><tr
 		><td class="src"
@@ -62,13 +90,15 @@ window.onload = function () {pageLoad();setSynopsis("mini_TypeFamilies2.html");}
 		    >data</span
 		    > <a href="TypeFamilies2.html#t:Bar"
 		    >Bar</a
-		    > <a href="TypeFamilies2.html#t:X"
-		    >X</a
+		    > <a href="TypeFamilies2.html#t:W"
+		    >W</a
 		    > = <a name="v:BarX" class="def"
 		    >BarX</a
-		    > Y</td
-		  ><td class="doc empty"
-		  >&nbsp;</td
+		    > Z</td
+		  ><td class="doc"
+		  ><p
+		    >Shown because BarX is still exported despite Z being hidden</p
+		    ></td
 		  ></tr
 		><tr
 		><td class="src"
@@ -76,11 +106,13 @@ window.onload = function () {pageLoad();setSynopsis("mini_TypeFamilies2.html");}
 		    >type</span
 		    > <a href="TypeFamilies2.html#t:Foo"
 		    >Foo</a
-		    > <a href="TypeFamilies2.html#t:X"
-		    >X</a
-		    > = Y</td
-		  ><td class="doc empty"
-		  >&nbsp;</td
+		    > <a href="TypeFamilies2.html#t:W"
+		    >W</a
+		    ></td
+		  ><td class="doc"
+		  ><p
+		    >Should be visible, but with a hidden right hand side</p
+		    ></td
 		  ></tr
 		></table
 	      ></div
@@ -93,6 +125,10 @@ window.onload = function () {pageLoad();setSynopsis("mini_TypeFamilies2.html");}
 	    > <a name="t:Foo" class="def"
 	    >Foo</a
 	    > a</p
+	  ><div class="doc"
+	  ><p
+	    >Exported type family</p
+	    ></div
 	  ><div class="subs instances"
 	  ><p id="control.i:Foo" class="caption collapser" onclick="toggleSection('i:Foo')"
 	    >Instances</p
@@ -104,11 +140,13 @@ window.onload = function () {pageLoad();setSynopsis("mini_TypeFamilies2.html");}
 		    >type</span
 		    > <a href="TypeFamilies2.html#t:Foo"
 		    >Foo</a
-		    > <a href="TypeFamilies2.html#t:X"
-		    >X</a
-		    > = Y</td
-		  ><td class="doc empty"
-		  >&nbsp;</td
+		    > <a href="TypeFamilies2.html#t:W"
+		    >W</a
+		    ></td
+		  ><td class="doc"
+		  ><p
+		    >Should be visible, but with a hidden right hand side</p
+		    ></td
 		  ></tr
 		><tr
 		><td class="src"
@@ -137,6 +175,10 @@ window.onload = function () {pageLoad();setSynopsis("mini_TypeFamilies2.html");}
 	    > <a name="t:Bar" class="def"
 	    >Bar</a
 	    > a</p
+	  ><div class="doc"
+	  ><p
+	    >Exported data family</p
+	    ></div
 	  ><div class="subs instances"
 	  ><p id="control.i:Bar" class="caption collapser" onclick="toggleSection('i:Bar')"
 	    >Instances</p
@@ -148,13 +190,15 @@ window.onload = function () {pageLoad();setSynopsis("mini_TypeFamilies2.html");}
 		    >data</span
 		    > <a href="TypeFamilies2.html#t:Bar"
 		    >Bar</a
-		    > <a href="TypeFamilies2.html#t:X"
-		    >X</a
+		    > <a href="TypeFamilies2.html#t:W"
+		    >W</a
 		    > = <a name="v:BarX" class="def"
 		    >BarX</a
-		    > Y</td
-		  ><td class="doc empty"
-		  >&nbsp;</td
+		    > Z</td
+		  ><td class="doc"
+		  ><p
+		    >Shown because BarX is still exported despite Z being hidden</p
+		    ></td
 		  ></tr
 		><tr
 		><td class="src"
diff --git a/html-test/src/TypeFamilies2.hs b/html-test/src/TypeFamilies2.hs
index 34790a51..b66acbfa 100644
--- a/html-test/src/TypeFamilies2.hs
+++ b/html-test/src/TypeFamilies2.hs
@@ -6,18 +6,34 @@
 --
 -- The other families and instances that are not exported should not
 -- show up at all
-module TypeFamilies2 (X, Foo, Bar) where
+module TypeFamilies2 (W, Foo, Bar) where
 
-data X
-data Y
+-- | Exported type
+data W
 
+-- | Hidden type
+data Z
+
+-- | Exported type family
 type family Foo a
-type instance Foo X = Y
-type instance Foo Y = X -- Should be hidden
 
+-- | Should be visible, but with a hidden right hand side
+type instance Foo W = Z
+
+-- | Should be hidden
+type instance Foo Z = W
+
+-- | Exported data family
 data family Bar a
-data instance Bar X = BarX Y
 
+-- | Shown because BarX is still exported despite Z being hidden
+data instance Bar W = BarX Z
+
+-- | Should be completely invisible, including instances
 type family Invisible a
-type instance Invisible X = Y
-type instance Invisible Y = X
+type instance Invisible W = Z
+type instance Invisible Z = W
+
+data family Invisible2 a
+data instance Invisible2 W = Invis  Z
+data instance Invisible2 Z = Invis' W
diff --git a/src/Haddock/Backends/LaTeX.hs b/src/Haddock/Backends/LaTeX.hs
index 6535b24e..44b3fc35 100644
--- a/src/Haddock/Backends/LaTeX.hs
+++ b/src/Haddock/Backends/LaTeX.hs
@@ -563,7 +563,8 @@ ppInstDecl unicode instHead = keyword "instance" <+> ppInstHead unicode instHead
 ppInstHead :: Bool -> InstHead DocName -> LaTeX
 ppInstHead unicode (n, ks, ts, ClassInst ctx) = ppContextNoLocs ctx unicode <+> ppAppNameTypes n ks ts unicode
 ppInstHead unicode (n, ks, ts, TypeInst rhs) = keyword "type"
-  <+> ppAppNameTypes n ks ts unicode <+> equals <+> ppType unicode rhs
+  <+> ppAppNameTypes n ks ts unicode
+  <+> maybe empty (\t -> equals <+> ppType unicode t) rhs
 ppInstHead _unicode (_n, _ks, _ts, DataInst _dd) =
   error "data instances not supported by --latex yet"
 
diff --git a/src/Haddock/Backends/Xhtml/Decl.hs b/src/Haddock/Backends/Xhtml/Decl.hs
index c0efa5d0..c1b9032e 100644
--- a/src/Haddock/Backends/Xhtml/Decl.hs
+++ b/src/Haddock/Backends/Xhtml/Decl.hs
@@ -488,7 +488,7 @@ ppInstances instances baseName unicode qual
         <+> ppAppNameTypes n ks ts unicode qual
     instHead (n, ks, ts, TypeInst rhs) = keyword "type"
         <+> ppAppNameTypes n ks ts unicode qual
-        <+> equals <+> ppType unicode qual rhs
+        <+> maybe noHtml (\t -> equals <+> ppType unicode qual t) rhs
     instHead (n, ks, ts, DataInst dd) = keyword "data"
         <+> ppAppNameTypes n ks ts unicode qual
         <+> ppShortDataDecl False True dd unicode qual
diff --git a/src/Haddock/Convert.hs b/src/Haddock/Convert.hs
index 3670473d..1245b2b9 100644
--- a/src/Haddock/Convert.hs
+++ b/src/Haddock/Convert.hs
@@ -380,13 +380,14 @@ synifyInstHead (_, preds, cls, types) =
   where (ks,ts) = break (not . isKind) types
 
 -- Convert a family instance, this could be a type family or data family
-synifyFamInst :: FamInst -> InstHead Name
-synifyFamInst fi =
+synifyFamInst :: FamInst -> Bool -> InstHead Name
+synifyFamInst fi opaque =
   ( fi_fam fi
   , map (unLoc . synifyType WithinType) ks
   , map (unLoc . synifyType WithinType) ts
   , case fi_flavor fi of
-      SynFamilyInst -> TypeInst . unLoc . synifyType WithinType $ fi_rhs fi
+      SynFamilyInst | opaque -> TypeInst Nothing
+      SynFamilyInst -> TypeInst . Just . unLoc . synifyType WithinType $ fi_rhs fi
       DataFamilyInst c -> DataInst $ synifyTyCon (Just $ famInstAxiom fi) c
   )
   where (ks,ts) = break (not . isKind) $ fi_tys fi
diff --git a/src/Haddock/Interface/AttachInstances.hs b/src/Haddock/Interface/AttachInstances.hs
index 60ae4661..a0bac8fc 100644
--- a/src/Haddock/Interface/AttachInstances.hs
+++ b/src/Haddock/Interface/AttachInstances.hs
@@ -70,13 +70,12 @@ attachToExportItem expInfo iface ifaceMap instIfaceMap export =
               expItemInstances =
                 case mb_info of
                   Just (_, _, cls_instances, fam_instances) ->
-                    let fam_insts = [ (synifyFamInst i, n)
+                    let fam_insts = [ (synifyFamInst i opaque, n)
                                     | i <- sortBy (comparing instFam) fam_instances
                                     , let n = instLookup instDocMap (getName i) iface ifaceMap instIfaceMap
                                     , not $ isNameHidden expInfo (fi_fam i)
                                     , not $ any (isTypeHidden expInfo) (fi_tys i)
-                                    -- Should we check for hidden RHS as well?
-                                    -- Ideally, in that case the RHS should simply not show up
+                                    , let opaque = isTypeHidden expInfo (fi_rhs i)
                                     ]
                         cls_insts = [ (synifyInstHead i, instLookup instDocMap n iface ifaceMap instIfaceMap)
                                     | let is = [ (instanceHead' i, getName i) | i <- cls_instances ]
diff --git a/src/Haddock/Interface/Rename.hs b/src/Haddock/Interface/Rename.hs
index a5cde195..4160f4f7 100644
--- a/src/Haddock/Interface/Rename.hs
+++ b/src/Haddock/Interface/Rename.hs
@@ -264,7 +264,7 @@ renameInstHead (className, k, types, rest) = do
   types' <- mapM renameType types
   rest' <- case rest of
     ClassInst cs -> ClassInst <$> mapM renameType cs
-    TypeInst  ts -> TypeInst  <$> renameType ts
+    TypeInst  ts -> TypeInst  <$> traverse renameType ts
     DataInst  dd -> DataInst  <$> renameTyClD dd
   return (className', k', types', rest')
 
diff --git a/src/Haddock/Types.hs b/src/Haddock/Types.hs
index 9538f3bf..5930c930 100644
--- a/src/Haddock/Types.hs
+++ b/src/Haddock/Types.hs
@@ -291,9 +291,9 @@ instance NamedThing DocName where
 
 -- | The three types of instances
 data InstType name
-  = ClassInst [HsType name]  -- ^ Context
-  | TypeInst  (HsType name)  -- ^ Body (right-hand side)
-  | DataInst (TyClDecl name) -- ^ Data constructors
+  = ClassInst [HsType name]         -- ^ Context
+  | TypeInst  (Maybe (HsType name)) -- ^ Body (right-hand side)
+  | DataInst (TyClDecl name)        -- ^ Data constructors
 
 instance OutputableBndr a => Outputable (InstType a) where
   ppr (ClassInst a) = text "ClassInst" <+> ppr a