aboutsummaryrefslogtreecommitdiff
path: root/haddock-api
diff options
context:
space:
mode:
Diffstat (limited to 'haddock-api')
-rw-r--r--haddock-api/src/Haddock/Backends/Hyperlinker.hs12
-rw-r--r--haddock-api/src/Haddock/Interface.hs54
2 files changed, 60 insertions, 6 deletions
diff --git a/haddock-api/src/Haddock/Backends/Hyperlinker.hs b/haddock-api/src/Haddock/Backends/Hyperlinker.hs
index 39be6762..68e03fd5 100644
--- a/haddock-api/src/Haddock/Backends/Hyperlinker.hs
+++ b/haddock-api/src/Haddock/Backends/Hyperlinker.hs
@@ -22,7 +22,7 @@ import System.FilePath
import GHC.Iface.Ext.Types ( pattern HiePath, HieFile(..), HieASTs(..), HieAST(..), SourcedNodeInfo(..) )
import GHC.Iface.Ext.Binary ( readHieFile, hie_file_result )
-import GHC.Types.SrcLoc ( realSrcLocSpan, mkRealSrcLoc )
+import GHC.Types.SrcLoc ( realSrcLocSpan, mkRealSrcLoc, srcSpanFile )
import Data.Map as M
import GHC.Data.FastString ( mkFastString )
import GHC.Unit.Module ( Module, moduleName )
@@ -71,7 +71,7 @@ ppHyperlinkedModuleSource verbosity srcdir pretty srcs iface = case ifaceHieFile
let fileFs = mkFastString file
mast | M.size asts == 1 = snd <$> M.lookupMin asts
| otherwise = M.lookup (HiePath (mkFastString file)) asts
- tokens = parse df file rawSrc
+ tokens' = parse df file rawSrc
ast = fromMaybe (emptyHieAst fileFs) mast
fullAst = recoverFullIfaceTypes df types ast
@@ -81,6 +81,14 @@ ppHyperlinkedModuleSource verbosity srcdir pretty srcs iface = case ifaceHieFile
else out verbosity verbose $ unwords [ "couldn't find ast for"
, file, show (M.keys asts) ]
+ -- The C preprocessor can double the backslashes on tokens (see #19236),
+ -- which means the source spans will not be comparable and we will not
+ -- be able to associate the HieAST with the correct tokens.
+ --
+ -- We work around this by setting the source span of the tokens to the file
+ -- name from the HieAST
+ let tokens = fmap (\tk -> tk {tkSpan = (tkSpan tk){srcSpanFile = srcSpanFile $ nodeSpan fullAst}}) tokens'
+
-- Produce and write out the hyperlinked sources
writeUtf8File path . renderToString pretty . render' fullAst $ tokens
Nothing -> return ()
diff --git a/haddock-api/src/Haddock/Interface.hs b/haddock-api/src/Haddock/Interface.hs
index 2e9b2f7e..ba7d9d30 100644
--- a/haddock-api/src/Haddock/Interface.hs
+++ b/haddock-api/src/Haddock/Interface.hs
@@ -55,7 +55,7 @@ import qualified Data.Set as Set
import GHC hiding (verbosity)
import GHC.Data.FastString (unpackFS)
-import GHC.Data.Graph.Directed (flattenSCCs)
+import GHC.Data.Graph.Directed
import GHC.Driver.Env (hscUpdateFlags, hsc_home_unit, hsc_logger, hsc_static_plugins, hsc_units)
import GHC.Driver.Monad (modifySession, withTimingM)
import GHC.Driver.Session hiding (verbosity)
@@ -68,7 +68,7 @@ import GHC.Types.Name (nameIsFromExternalPackage, nameOccName)
import GHC.Types.Name.Occurrence (isTcOcc)
import GHC.Types.Name.Reader (globalRdrEnvElts, greMangledName, unQualOK)
import GHC.Unit.Module.Env (ModuleSet, emptyModuleSet, mkModuleSet, unionModuleSet)
-import GHC.Unit.Module.Graph (ModuleGraphNode (..))
+import GHC.Unit.Module.Graph
import GHC.Unit.Module.ModSummary (emsModSummary, isBootSummary)
import GHC.Unit.Types (IsBootInterface (..))
import GHC.Utils.Error (withTiming)
@@ -170,13 +170,59 @@ createIfaces verbosity modules flags instIfaceMap = do
moduleSet <- liftIO getModules
let
+ -- We topologically sort the module graph including boot files,
+ -- so it should be acylic (hopefully we failed much earlier if this is not the case)
+ -- We then filter out boot modules from the resultant topological sort
+ --
+ -- We do it this way to make 'buildHomeLinks' a bit more stable
+ -- 'buildHomeLinks' depends on the topological order of its input in order
+ -- to construct its result. In particular, modules closer to the bottom of
+ -- the dependency chain are to be prefered for link destinations.
+ --
+ -- If there are cycles in the graph, then this order is indeterminate
+ -- (the nodes in the cycle can be ordered in any way).
+ -- While 'topSortModuleGraph' does guarantee stability for equivalent
+ -- module graphs, seemingly small changes in the ModuleGraph can have
+ -- big impacts on the `LinkEnv` constructed.
+ --
+ -- For example, suppose
+ -- G1 = A.hs -> B.hs -> C.hs (where '->' denotes an import).
+ --
+ -- Then suppose C.hs is changed to have a cyclic dependency on A
+ --
+ -- G2 = A.hs -> B.hs -> C.hs -> A.hs-boot
+ --
+ -- For G1, `C.hs` is preferred for link destinations. However, for G2,
+ -- the topologically sorted order not taking into account boot files (so
+ -- C -> A) is completely indeterminate.
+ -- Using boot files to resolve cycles, we end up with the original order
+ -- [C, B, A] (in decreasing order of preference for links)
+ --
+ -- This exact case came up in testing for the 'base' package, where there
+ -- is a big module cycle involving 'Prelude' on windows, but the cycle doesn't
+ -- include 'Prelude' on non-windows platforms. This lead to drastically different
+ -- LinkEnv's (and failing haddockHtmlTests) across the platforms
+ --
+ -- In effect, for haddock users this behaviour (using boot files to eliminate cycles)
+ -- means that {-# SOURCE #-} imports no longer count towards re-ordering
+ -- the preference of modules for linking.
+ --
+ -- i.e. if module A imports B, then B is preferred over A,
+ -- but if module A {-# SOURCE #-} imports B, then we can't say the same.
+ --
+ go (AcyclicSCC (ModuleNode ems))
+ | NotBoot <- isBootSummary (emsModSummary ems) = [ems]
+ | otherwise = []
+ go (AcyclicSCC _) = []
+ go (CyclicSCC _) = error "haddock: module graph cyclic even with boot files"
+
ifaces :: [Interface]
ifaces =
[ Map.findWithDefault
(error "haddock:iface")
(ms_mod (emsModSummary ems))
ifaceMap
- | ModuleNode ems <- flattenSCCs $ topSortModuleGraph True modGraph Nothing
+ | ems <- concatMap go $ topSortModuleGraph False modGraph Nothing
]
return (ifaces, moduleSet)
@@ -352,7 +398,7 @@ processModule1 verbosity flags ifaces inst_ifaces hsc_env mod_summary tc_gbl_env
-- The interfaces are passed in in topologically sorted order, but we start
-- by reversing the list so we can do a foldl.
buildHomeLinks :: [Interface] -> LinkEnv
-buildHomeLinks ifaces = foldl upd Map.empty (reverse ifaces)
+buildHomeLinks ifaces = foldl' upd Map.empty (reverse ifaces)
where
upd old_env iface
| OptHide `elem` ifaceOptions iface = old_env