From ba4ae3d08bd9a9c3cd0453526b7763cad5524ee6 Mon Sep 17 00:00:00 2001
From: Iain Nicol <iain@iainnicol.com>
Date: Sat, 10 May 2014 13:44:26 +0100
Subject: [PATCH] Fix: "cabal haddock" uses CPP overzealously
Until recently we supported ancient versions of Haddock, pre v2.0. To
support the CPP extension with such versions, cabal had to invoke the
CPP before invoking Haddock on the output. For simplicity cabal would
invoke the CPP on all Haskell files, if any Haskell file required CPP.
However, invoking CPP on a file which does not require it can cause
build failures.
Haddock v2.0+ supports the CPP via GHC, and even automatically
preprocesses any file with the {-# LANGUAGE CPP #-} pragma. Hence we
simply need only tell Haddock to enable the CPP when the CPP is a
package level default extension.
Fixes issue #1808.
---
Cabal/Cabal.cabal | 1 +
Cabal/Distribution/Simple/Haddock.hs | 4 ++--
Cabal/tests/PackageTests/Haddock/Check.hs | 2 +-
Cabal/tests/PackageTests/Haddock/NoCPP.hs | 8 ++++++++
Cabal/tests/PackageTests/Haddock/my.cabal | 2 +-
5 files changed, 13 insertions(+), 4 deletions(-)
create mode 100644 Cabal/tests/PackageTests/Haddock/NoCPP.hs
diff --git a/Cabal/Cabal.cabal b/Cabal/Cabal.cabal
index 711f4dea63..4bd11d9b04 100644
--- a/Cabal/Cabal.cabal
+++ b/Cabal/Cabal.cabal
@@ -83,6 +83,7 @@ extra-source-files:
tests/PackageTests/Haddock/CPP.hs
tests/PackageTests/Haddock/Literate.lhs
tests/PackageTests/Haddock/my.cabal
+ tests/PackageTests/Haddock/NoCPP.hs
tests/PackageTests/Haddock/Simple.hs
tests/PackageTests/OrderFlags/Foo.hs
tests/PackageTests/OrderFlags/my.cabal
diff --git a/Cabal/Distribution/Simple/Haddock.hs b/Cabal/Distribution/Simple/Haddock.hs
index 79c7d05054..7e1b10a72b 100644
--- a/Cabal/Distribution/Simple/Haddock.hs
+++ b/Cabal/Distribution/Simple/Haddock.hs
@@ -27,7 +27,7 @@ import Distribution.Package
, PackageName(..), packageName )
import qualified Distribution.ModuleName as ModuleName
import Distribution.PackageDescription as PD
- ( PackageDescription(..), BuildInfo(..), allExtensions
+ ( PackageDescription(..), BuildInfo(..), usedExtensions
, Library(..), hasLibs, Executable(..)
, TestSuite(..), TestSuiteInterface(..)
, Benchmark(..), BenchmarkInterface(..) )
@@ -365,7 +365,7 @@ getGhcCppOpts haddockVersion bi =
ghcOptCppOptions = defines
}
where
- needsCpp = EnableExtension CPP `elem` allExtensions bi
+ needsCpp = EnableExtension CPP `elem` usedExtensions bi
defines = [haddockVersionMacro]
haddockVersionMacro = "-D__HADDOCK_VERSION__="
++ show (v1 * 1000 + v2 * 10 + v3)
diff --git a/Cabal/tests/PackageTests/Haddock/Check.hs b/Cabal/tests/PackageTests/Haddock/Check.hs
index cbfe522c07..0d41dd4515 100644
--- a/Cabal/tests/PackageTests/Haddock/Check.hs
+++ b/Cabal/tests/PackageTests/Haddock/Check.hs
@@ -26,7 +26,7 @@ suite ghcPath = TestCase $ do
assertHaddockSucceeded hResult
let docFiles = map (haddocksDir </>)
- ["CPP.html", "Literate.html", "Simple.html"]
+ ["CPP.html", "Literate.html", "NoCPP.html", "Simple.html"]
mapM_ (assertFindInFile "For hiding needles.") docFiles
assertFindInFile :: String -> FilePath -> Assertion
diff --git a/Cabal/tests/PackageTests/Haddock/NoCPP.hs b/Cabal/tests/PackageTests/Haddock/NoCPP.hs
new file mode 100644
index 0000000000..417f368b37
--- /dev/null
+++ b/Cabal/tests/PackageTests/Haddock/NoCPP.hs
@@ -0,0 +1,8 @@
+module NoCPP (Haystack) where
+
+-- | For hiding needles.
+data Haystack = Haystack
+
+-- | Causes a build failure if the CPP language extension is enabled.
+stringGap = "Foo\
+\Bar"
diff --git a/Cabal/tests/PackageTests/Haddock/my.cabal b/Cabal/tests/PackageTests/Haddock/my.cabal
index 63e9faa4a7..176ced9b4d 100644
--- a/Cabal/tests/PackageTests/Haddock/my.cabal
+++ b/Cabal/tests/PackageTests/Haddock/my.cabal
@@ -11,6 +11,6 @@ description:
Check that Cabal successfully invokes Haddock.
Library
- exposed-modules: CPP, Literate, Simple
+ exposed-modules: CPP, Literate, NoCPP, Simple
other-extensions: CPP
build-depends: base
--
GitLab