Add the docspec:base rule to Hadrian

4 files changed, 63 insertions, 0 deletions

diff --git a/hadrian/hadrian.cabal b/hadrian/hadrian.cabal
index 3bca30ff23..0b54bed039 100644
--- a/hadrian/hadrian.cabal
+++ b/hadrian/hadrian.cabal
@@ -68,6 +68,7 @@ executable hadrian
                        , Rules.Compile
                        , Rules.Configure
                        , Rules.Dependencies
+                       , Rules.Docspec
                        , Rules.Documentation
                        , Rules.Generate
                        , Rules.Gmp
diff --git a/hadrian/src/Main.hs b/hadrian/src/Main.hs
index d75bc743a7..db808f5a57 100644
--- a/hadrian/src/Main.hs
+++ b/hadrian/src/Main.hs
@@ -11,6 +11,7 @@ import qualified CommandLine
 import qualified Environment
 import qualified Rules
 import qualified Rules.Clean
+import qualified Rules.Docspec
 import qualified Rules.Documentation
 import qualified Rules.Lint
 import qualified Rules.Nofib
@@ -83,6 +84,7 @@ main = do
         rules :: Rules ()
         rules = do
             Rules.buildRules
+            Rules.Docspec.docspecRules
             Rules.Documentation.documentationRules
             Rules.Clean.cleanRules
             Rules.Lint.lintRules
diff --git a/hadrian/src/Rules/Docspec.hs b/hadrian/src/Rules/Docspec.hs
new file mode 100644
index 0000000000..e5f8eb66c4
--- /dev/null
+++ b/hadrian/src/Rules/Docspec.hs
@@ -0,0 +1,57 @@
+module Rules.Docspec
+  ( docspecRules
+  ) where
+
+import System.Directory (findExecutable)
+
+import Base
+import Context.Path
+import Settings.Builders.Common
+import qualified Packages as P
+
+docspecRules :: Rules ()
+docspecRules = do
+  "docspec:base" ~> docspec base
+
+docspec :: Action () -> Action ()
+docspec lintAction = do
+  isExecutablePresent <- isJust <$> liftIO (findExecutable "cabal-docspec")
+  if isExecutablePresent
+  then do
+    putBuild "| Running cabal-docspec…"
+    lintAction
+    putSuccess "| Done."
+  else
+    putFailure "| Please make sure you have the `cabal-docspec` executable in your $PATH"
+
+base :: Action ()
+base = do
+  topDir   <- topDirectory
+  let context = vanillaContext Stage1 P.base
+  stage1GHCPath <- P.programPath (vanillaContext Stage1 P.ghc)
+  let stage1GHC = topDir </> stage1GHCPath
+  stage1Lib <- stageLibPath Stage1
+  let cabalFile = pkgCabalFile P.base
+  let topIncludes = topDir </> "includes"
+  includeDeps' <- includesDependencies Stage1
+  buildPath' <- buildPath context
+  let buildIncludesPath = topDir </> buildPath' </> "include"
+  let includeDeps = fmap (topDir </>) includeDeps'
+  mtlConfFile <- pkgConfFile $ vanillaContext Stage1 P.mtl
+  deepseqConfFile <- pkgConfFile $ vanillaContext Stage1 P.deepseq
+  bytestringConfFile <- pkgConfFile $ vanillaContext Stage1 P.bytestring
+  let neededIncludes = includeDeps ++ [mtlConfFile, deepseqConfFile, bytestringConfFile]
+  need neededIncludes
+
+  command_ [] "cabal-docspec" [ "-w", stage1GHC
+                              , "--no-cabal-plan"
+                              , "--strip-comments"
+                              , "--timeout", "2"
+                              , "--ghci-rtsopts=-K500K"
+                              , "--extra-package=mtl", "--extra-package=deepseq", "--extra-package=bytestring"
+                              , "-XNoImplicitPrelude"
+                              , "-I", topIncludes
+                              , "-I", buildIncludesPath
+                              , "-I", stage1Lib
+                              , cabalFile
+                              ]
diff --git a/libraries/base/Data/List/NonEmpty.hs b/libraries/base/Data/List/NonEmpty.hs
index d66d9c6a92..84e909a25a 100644
--- a/libraries/base/Data/List/NonEmpty.hs
+++ b/libraries/base/Data/List/NonEmpty.hs
@@ -113,6 +113,9 @@ import           GHC.Base            (NonEmpty(..))
 
 infixr 5 <|
 
+-- $setup
+-- >>> import Prelude (negate)
+
 -- | Number of elements in 'NonEmpty' list.
 length :: NonEmpty a -> Int
 length (_ :| xs) = 1 + Prelude.length xs