Render module tree per package in the content page (#1492)

* Render module tree per package in the content page

When rendering content page for multiple packages it is useful to split
the module tree per package.  Package names in this patch are inferred
from haddock's interface file names.

* Write PackageInfo into interface file

To keep interface file format backward compatible, instead of using
`Binary` instance for `InterfaceFile` we introduce functions to
serialise and deserialise, which depends on the interface file version.

3 files changed, 146 insertions, 36 deletions

diff --git a/haddock-api/src/Haddock/Backends/Xhtml.hs b/haddock-api/src/Haddock/Backends/Xhtml.hs
index 55783c67..3dc1e8da 100644
--- a/haddock-api/src/Haddock/Backends/Xhtml.hs
+++ b/haddock-api/src/Haddock/Backends/Xhtml.hs
@@ -28,7 +28,9 @@ import Haddock.Backends.Xhtml.Names
 import Haddock.Backends.Xhtml.Themes
 import Haddock.Backends.Xhtml.Types
 import Haddock.Backends.Xhtml.Utils
+import Haddock.InterfaceFile (PackageInfo (..), PackageInterfaces (..), ppPackageInfo)
 import Haddock.ModuleTree
+import Haddock.Options (Visibility (..))
 import Haddock.Types
 import Haddock.Version
 import Haddock.Utils
@@ -78,6 +80,7 @@ ppHtml :: UnitState
        -> Maybe String                 -- ^ The index URL (--use-index)
        -> Bool                         -- ^ Whether to use unicode in output (--use-unicode)
        -> Maybe String                 -- ^ Package name
+       -> PackageInfo                  -- ^ Package info
        -> QualOption                   -- ^ How to qualify names
        -> Bool                         -- ^ Output pretty html (newlines and indenting)
        -> Bool                         -- ^ Also write Quickjump index
@@ -86,7 +89,7 @@ ppHtml :: UnitState
 ppHtml state doctitle maybe_package ifaces reexported_ifaces odir prologue
         themes maybe_mathjax_url maybe_source_url maybe_wiki_url
         maybe_base_url maybe_contents_url maybe_index_url unicode
-        pkg qual debug withQuickjump = do
+        pkg packageInfo qual debug withQuickjump = do
   let
     visible_ifaces = filter visible ifaces
     visible i = OptHide `notElem` ifaceOptions i
@@ -94,7 +97,12 @@ ppHtml state doctitle maybe_package ifaces reexported_ifaces odir prologue
   when (isNothing maybe_contents_url) $
     ppHtmlContents state odir doctitle maybe_package
         themes maybe_mathjax_url maybe_index_url maybe_source_url maybe_wiki_url
-        (map toInstalledIface visible_ifaces ++ reexported_ifaces)
+        [PackageInterfaces
+          { piPackageInfo = packageInfo
+          , piVisibility  = Visible
+          , piInstalledInterfaces = map toInstalledIface visible_ifaces
+                                 ++ reexported_ifaces
+          }]
         False -- we don't want to display the packages in a single-package contents
         prologue debug pkg (makeContentsQual qual)
 
@@ -277,30 +285,42 @@ ppHtmlContents
    -> Maybe String
    -> SourceURLs
    -> WikiURLs
-   -> [InstalledInterface] -> Bool -> Maybe (MDoc GHC.RdrName)
+   -> [PackageInterfaces] -> Bool -> Maybe (MDoc GHC.RdrName)
    -> Bool
    -> Maybe Package  -- ^ Current package
    -> Qualification  -- ^ How to qualify names
    -> IO ()
 ppHtmlContents state odir doctitle _maybe_package
   themes mathjax_url maybe_index_url
-  maybe_source_url maybe_wiki_url ifaces showPkgs prologue debug pkg qual = do
-  let tree = mkModuleTree state showPkgs
-         [(instMod iface, toInstalledDescription iface)
-         | iface <- ifaces
-         , not (instIsSig iface)]
-      sig_tree = mkModuleTree state showPkgs
-         [(instMod iface, toInstalledDescription iface)
-         | iface <- ifaces
-         , instIsSig iface]
+  maybe_source_url maybe_wiki_url packages showPkgs prologue debug pkg qual = do
+  let trees =
+        [ ( piPackageInfo pinfo
+          , mkModuleTree state showPkgs
+            [(instMod iface, toInstalledDescription iface)
+            | iface <- piInstalledInterfaces pinfo
+            , not (instIsSig iface)
+            ]
+          )
+        | pinfo <- packages
+        ]
+      sig_trees =
+        [ ( piPackageInfo pinfo
+          , mkModuleTree state showPkgs
+            [(instMod iface, toInstalledDescription iface)
+            | iface <- piInstalledInterfaces pinfo
+            , instIsSig iface
+            ]
+          )
+        | pinfo <- packages
+        ]
       html =
         headHtml doctitle themes mathjax_url Nothing +++
         bodyHtml doctitle Nothing
           maybe_source_url maybe_wiki_url
           Nothing maybe_index_url << [
             ppPrologue pkg qual doctitle prologue,
-            ppSignatureTree pkg qual sig_tree,
-            ppModuleTree pkg qual tree
+            ppSignatureTrees pkg qual sig_trees,
+            ppModuleTrees pkg qual trees
           ]
   createDirectoryIfMissing True odir
   writeUtf8File (joinPath [odir, contentsHtmlFile]) (renderToString debug html)
@@ -315,17 +335,37 @@ ppPrologue _ _ _ Nothing = noHtml
 ppPrologue pkg qual title (Just doc) =
   divDescription << (h1 << title +++ docElement thediv (rdrDocToHtml pkg qual doc))
 
-
-ppSignatureTree :: Maybe Package -> Qualification -> [ModuleTree] -> Html
-ppSignatureTree _ _ [] = mempty
-ppSignatureTree pkg qual ts =
-  divModuleList << (sectionName << "Signatures" +++ mkNodeList pkg qual [] "n" ts)
-
-
-ppModuleTree :: Maybe Package -> Qualification -> [ModuleTree] -> Html
-ppModuleTree _ _ [] = mempty
-ppModuleTree pkg qual ts =
-  divModuleList << (sectionName << "Modules" +++ mkNodeList pkg qual [] "n" ts)
+ppSignatureTrees :: Maybe Package -> Qualification -> [(PackageInfo, [ModuleTree])] -> Html
+ppSignatureTrees _ _ tss | all (null . snd) tss = mempty
+ppSignatureTrees pkg qual [(info, ts)] = 
+  divPackageList << (sectionName << "Signatures" +++ ppSignatureTree pkg qual "n" info ts)
+ppSignatureTrees pkg qual tss =
+  divModuleList <<
+    (sectionName << "Signatures"
+     +++ concatHtml [ ppSignatureTree pkg qual("n."++show i++".") info ts
+                    | (i, (info, ts)) <- zip [(1::Int)..] tss
+                    ])
+
+ppSignatureTree :: Maybe Package -> Qualification -> String -> PackageInfo -> [ModuleTree] -> Html
+ppSignatureTree _ _ _ _ [] = mempty
+ppSignatureTree pkg qual p info ts =
+  divModuleList << (sectionName << ppPackageInfo info +++ mkNodeList pkg qual [] p ts)
+
+ppModuleTrees :: Maybe Package -> Qualification -> [(PackageInfo, [ModuleTree])] -> Html
+ppModuleTrees _ _ tss | all (null . snd) tss = mempty
+ppModuleTrees pkg qual [(info, ts)] =
+  divModuleList << (sectionName << "Modules" +++ ppModuleTree pkg qual "n" info ts)
+ppModuleTrees pkg qual tss =
+  divPackageList <<
+    (sectionName << "Packages"
+     +++ concatHtml [ppModuleTree pkg qual ("n."++show i++".") info ts
+                    | (i, (info, ts)) <- zip [(1::Int)..] tss
+                    ])
+
+ppModuleTree :: Maybe Package -> Qualification -> String -> PackageInfo -> [ModuleTree] -> Html
+ppModuleTree _ _ _ _ [] = mempty
+ppModuleTree pkg qual p info ts =
+  divModuleList << (sectionName << ppPackageInfo info +++ mkNodeList pkg qual [] p ts)
 
 
 mkNodeList :: Maybe Package -> Qualification -> [String] -> String -> [ModuleTree] -> Html
diff --git a/haddock-api/src/Haddock/Backends/Xhtml/Layout.hs b/haddock-api/src/Haddock/Backends/Xhtml/Layout.hs
index 8f04a21f..18405db8 100644
--- a/haddock-api/src/Haddock/Backends/Xhtml/Layout.hs
+++ b/haddock-api/src/Haddock/Backends/Xhtml/Layout.hs
@@ -15,7 +15,7 @@ module Haddock.Backends.Xhtml.Layout (
 
   divPackageHeader, divContent, divModuleHeader, divFooter,
   divTableOfContents, divDescription, divSynopsis, divInterface,
-  divIndex, divAlphabet, divModuleList, divContentsList,
+  divIndex, divAlphabet, divPackageList, divModuleList,  divContentsList,
 
   sectionName,
   nonEmptySectionName,
@@ -81,7 +81,7 @@ nonEmptySectionName c
 
 divPackageHeader, divContent, divModuleHeader, divFooter,
   divTableOfContents, divDescription, divSynopsis, divInterface,
-  divIndex, divAlphabet, divModuleList, divContentsList
+  divIndex, divAlphabet, divPackageList, divModuleList, divContentsList
     :: Html -> Html
 
 divPackageHeader    = sectionDiv "package-header"
@@ -96,6 +96,7 @@ divInterface        = sectionDiv "interface"
 divIndex            = sectionDiv "index"
 divAlphabet         = sectionDiv "alphabet"
 divModuleList       = sectionDiv "module-list"
+divPackageList      = sectionDiv "module-list"
 
 
 --------------------------------------------------------------------------------
diff --git a/haddock-api/src/Haddock/InterfaceFile.hs b/haddock-api/src/Haddock/InterfaceFile.hs
index bd83e734..fa51bcbc 100644
--- a/haddock-api/src/Haddock/InterfaceFile.hs
+++ b/haddock-api/src/Haddock/InterfaceFile.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE CPP, RankNTypes, ScopedTypeVariables #-}
 {-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE NamedFieldPuns #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 -----------------------------------------------------------------------------
 -- |
@@ -15,9 +16,10 @@
 -- Reading and writing the .haddock interface file
 -----------------------------------------------------------------------------
 module Haddock.InterfaceFile (
-  InterfaceFile(..), ifUnitId, ifModule,
-  readInterfaceFile, nameCacheFromGhc, freshNameCache, NameCacheAccessor,
-  writeInterfaceFile, binaryInterfaceVersion, binaryInterfaceVersionCompatibility
+  InterfaceFile(..), PackageInfo(..), ifUnitId, ifModule,
+  PackageInterfaces(..), mkPackageInterfaces, ppPackageInfo, readInterfaceFile,
+  nameCacheFromGhc, freshNameCache, NameCacheAccessor, writeInterfaceFile,
+  binaryInterfaceVersion, binaryInterfaceVersionCompatibility
 ) where
 
 
@@ -30,9 +32,12 @@ import Data.IORef
 import Data.List (mapAccumR)
 import qualified Data.Map as Map
 import Data.Map (Map)
+import Data.Version
 import Data.Word
+import Text.ParserCombinators.ReadP (readP_to_S)
 
 import GHC.Iface.Binary (getSymtabName, getDictFastString)
+import GHC.Unit.State
 import GHC.Utils.Binary
 import GHC.Data.FastMutInt
 import GHC.Data.FastString
@@ -46,11 +51,43 @@ import GHC.Types.Unique.FM
 import GHC.Types.Unique.Supply
 import GHC.Types.Unique
 
+import Haddock.Options (Visibility (..))
+
 data InterfaceFile = InterfaceFile {
   ifLinkEnv         :: LinkEnv,
+  -- | Package meta data.  Currently it only consist of a package name, which
+  -- is not read from the interface file, but inferred from its name.
+  --
+  -- issue #
+  ifPackageInfo     :: PackageInfo,
   ifInstalledIfaces :: [InstalledInterface]
 }
 
+data PackageInfo = PackageInfo {
+  piPackageName    :: PackageName,
+  piPackageVersion :: Data.Version.Version
+}
+
+ppPackageInfo :: PackageInfo -> String
+ppPackageInfo (PackageInfo name version) | version == makeVersion []
+                                         = unpackFS (unPackageName name)
+ppPackageInfo (PackageInfo name version) = unpackFS (unPackageName name) ++ "-" ++ showVersion version
+
+data PackageInterfaces = PackageInterfaces {
+  piPackageInfo         :: PackageInfo,
+  piVisibility          :: Visibility,
+  piInstalledInterfaces :: [InstalledInterface]
+}
+
+mkPackageInterfaces :: Visibility -> InterfaceFile -> PackageInterfaces
+mkPackageInterfaces piVisibility
+                    InterfaceFile { ifPackageInfo
+                                  , ifInstalledIfaces
+                                  } = 
+  PackageInterfaces { piPackageInfo = ifPackageInfo
+                    , piVisibility
+                    , piInstalledInterfaces = ifInstalledIfaces
+                    }
 
 ifModule :: InterfaceFile -> Module
 ifModule if_ =
@@ -95,10 +132,10 @@ binaryInterfaceMagic = 0xD0Cface
 --
 binaryInterfaceVersion :: Word16
 #if MIN_VERSION_ghc(9,2,0) && !MIN_VERSION_ghc(9,3,0)
-binaryInterfaceVersion = 38
+binaryInterfaceVersion = 39
 
 binaryInterfaceVersionCompatibility :: [Word16]
-binaryInterfaceVersionCompatibility = [37, binaryInterfaceVersion]
+binaryInterfaceVersionCompatibility = [37, 38, binaryInterfaceVersion]
 #elif defined(__HLINT__)
 #else
 #error Unsupported GHC version
@@ -139,7 +176,7 @@ writeInterfaceFile filename iface = do
   let bh = setUserData bh0 $ newWriteState (putName bin_symtab)
                                            (putName bin_symtab)
                                            (putFastString bin_dict)
-  put_ bh iface
+  putInterfaceFile_ bh iface
 
   -- write the symtab pointer at the front of the file
   symtab_p <- tellBin bh
@@ -228,7 +265,7 @@ readInterfaceFile (get_name_cache, set_name_cache) filename bypass_checks = do
                                                   (getDictFastString dict)
 
       -- load the actual data
-      iface <- liftIO $ get bh1
+      iface <- liftIO $ getInterfaceFile bh1 version
       return (Right iface)
  where
    with_name_cache :: forall a.
@@ -372,16 +409,48 @@ instance (Ord k, Binary k, Binary v) => Binary (Map k v) where
   put_ bh m = put_ bh (Map.toList m)
   get bh = fmap (Map.fromList) (get bh)
 
+instance Binary PackageInfo where
+  put_ bh PackageInfo { piPackageName, piPackageVersion } = do
+    put_ bh (unPackageName piPackageName)
+    put_ bh (showVersion piPackageVersion)
+  get bh = do
+    name <- PackageName <$> get bh
+    versionString <- get bh
+    let version = case readP_to_S parseVersion versionString of
+          [] -> makeVersion []
+          vs -> fst (last vs)
+    return $ PackageInfo name version
 
 instance Binary InterfaceFile where
-  put_ bh (InterfaceFile env ifaces) = do
+  put_ bh (InterfaceFile env info ifaces) = do
     put_ bh env
+    put_ bh info
     put_ bh ifaces
 
   get bh = do
     env    <- get bh
+    info   <- get bh
     ifaces <- get bh
-    return (InterfaceFile env ifaces)
+    return (InterfaceFile env info ifaces)
+
+
+putInterfaceFile_ :: BinHandle -> InterfaceFile -> IO ()
+putInterfaceFile_ bh (InterfaceFile env info ifaces) = do
+  put_ bh env
+  put_ bh info
+  put_ bh ifaces
+
+getInterfaceFile :: BinHandle -> Word16 -> IO InterfaceFile
+getInterfaceFile bh v | v <= 38 = do
+  env    <- get bh
+  let info = PackageInfo (PackageName mempty) (makeVersion [])
+  ifaces <- get bh
+  return (InterfaceFile env info ifaces)
+getInterfaceFile bh _ = do
+  env    <- get bh
+  info   <- get bh
+  ifaces <- get bh
+  return (InterfaceFile env info ifaces)
 
 
 instance Binary InstalledInterface where