nixpkgs/pkgs/development/haskell-modules/with-packages-wrapper.nix
Peter Simons afca6145d4 haskell-generic-builder: simplify "package.conf.d" management
The builder creates a temporary package.conf.d database in $TMP that
contains everything required to build the current package (i.e. the
transitive closure of the package's propagated build inputs). These
files are no longer installed, however, we just install the package.conf
file for the package we're actually building. This means that
package.conf.d directory in $out won't have collisions anymore, which
simplifies the with-packages-wrapper.nix a bit.
2015-01-10 15:55:47 +01:00

83 lines
2.8 KiB
Nix

{ stdenv, ghc, packages, buildEnv, makeWrapper, ignoreCollisions ? false }:
# This wrapper works only with GHC 6.12 or later.
assert stdenv.lib.versionOlder "6.12" ghc.version;
# It's probably a good idea to include the library "ghc-paths" in the
# compiler environment, because we have a specially patched version of
# that package in Nix that honors these environment variables
#
# NIX_GHC
# NIX_GHCPKG
# NIX_GHC_DOCDIR
# NIX_GHC_LIBDIR
#
# instead of hard-coding the paths. The wrapper sets these variables
# appropriately to configure ghc-paths to point back to the wrapper
# instead of to the pristine GHC package, which doesn't know any of the
# additional libraries.
#
# A good way to import the environment set by the wrapper below into
# your shell is to add the following snippet to your ~/.bashrc:
#
# if [ -e ~/.nix-profile/bin/ghc ]; then
# eval $(grep export ~/.nix-profile/bin/ghc)
# fi
let
ghc761OrLater = stdenv.lib.versionOlder "7.6.1" ghc.version;
packageDBFlag = if ghc761OrLater then "--global-package-db" else "--global-conf";
libDir = "$out/lib/ghc-${ghc.version}";
docDir = "$out/share/doc/ghc/html";
packageCfgDir = "${libDir}/package.conf.d";
isHaskellPkg = x: (x ? pname) && (x ? version);
paths = stdenv.lib.filter isHaskellPkg (stdenv.lib.closePropagation packages);
in
if paths == [] then ghc else
buildEnv {
inherit (ghc) name;
paths = paths ++ [ghc];
inherit ignoreCollisions;
postBuild = ''
. ${makeWrapper}/nix-support/setup-hook
if test -L "$out/bin"; then
binTarget="$(readlink -f "$out/bin")"
rm "$out/bin"
cp -r "$binTarget" "$out/bin"
chmod u+w "$out/bin"
fi
for prg in ghc ghci ghc-${ghc.version} ghci-${ghc.version}; do
rm -f $out/bin/$prg
makeWrapper ${ghc}/bin/$prg $out/bin/$prg \
--add-flags '"-B$NIX_GHC_LIBDIR"' \
--set "NIX_GHC" "$out/bin/ghc" \
--set "NIX_GHCPKG" "$out/bin/ghc-pkg" \
--set "NIX_GHC_DOCDIR" "${docDir}" \
--set "NIX_GHC_LIBDIR" "${libDir}"
done
for prg in runghc runhaskell; do
rm -f $out/bin/$prg
makeWrapper ${ghc}/bin/$prg $out/bin/$prg \
--add-flags "-f $out/bin/ghc" \
--set "NIX_GHC" "$out/bin/ghc" \
--set "NIX_GHCPKG" "$out/bin/ghc-pkg" \
--set "NIX_GHC_DOCDIR" "${docDir}" \
--set "NIX_GHC_LIBDIR" "${libDir}"
done
for prg in ghc-pkg ghc-pkg-${ghc.version}; do
rm -f $out/bin/$prg
makeWrapper ${ghc}/bin/$prg $out/bin/$prg --add-flags "${packageDBFlag}=${packageCfgDir}"
done
$out/bin/ghc-pkg recache
$out/bin/ghc-pkg check
'';
} // {
preferLocalBuild = true;
inherit (ghc) version meta;
}