core/pkgs/by-name/ha/haskell/haskell-modules/hoogle.nix
2024-05-13 22:37:40 -04:00

127 lines
4 KiB
Nix

# Install not only the Hoogle library and executable, but also a local Hoogle
# database which provides "Source" links to all specified 'packages' -- or the
# current Haskell Platform if no custom package set is provided.
{ lib, stdenv, buildPackages, haskellPackages
, writeText
}:
# This argument is a function which selects a list of Haskell packages from any
# passed Haskell package set.
#
# Example:
# (hpkgs: [ hpkgs.mtl hpkgs.lens ])
selectPackages:
let
inherit (haskellPackages) ghc hoogle;
packages = selectPackages haskellPackages;
wrapper = ./hoogle-local-wrapper.sh;
isGhcjs = ghc.isGhcjs or false;
opts = lib.optionalString;
haddockExe =
if !isGhcjs
then "haddock"
else "haddock-ghcjs";
ghcDocLibDir =
if !isGhcjs
then ghc.doc + "/share/doc/ghc*/html/libraries"
else ghc + "/doc/lib";
# On GHCJS, use a stripped down version of GHC's prologue.txt
prologue =
if !isGhcjs
then "${ghcDocLibDir}/prologue.txt"
else writeText "ghcjs-prologue.txt" ''
This index includes documentation for many Haskell modules.
'';
docPackages = lib.closePropagation
# we grab the doc outputs
(map (lib.getOutput "doc") packages);
in
buildPackages.stdenv.mkDerivation {
name = "hoogle-with-packages";
buildInputs = [ghc hoogle];
# compiling databases takes less time than copying the results
# between machines.
preferLocalBuild = true;
# we still allow substitutes because a database is relatively small and if it
# is already built downloading is probably faster. The substitution will only
# trigger for users who have already cached the database on a substituter and
# thus probably intend to substitute it.
allowSubstitutes = true;
inherit docPackages;
passAsFile = ["buildCommand"];
buildCommand = ''
${let # Filter out nulls here to work around https://github.com/NixOS/nixpkgs/issues/82245
# If we don't then grabbing `p.name` here will fail.
packages' = lib.filter (p: p != null) packages;
in lib.optionalString (packages' != [] -> docPackages == [])
("echo WARNING: localHoogle package list empty, even though"
+ " the following were specified: "
+ lib.concatMapStringsSep ", " (p: p.name) packages')}
mkdir -p $out/share/doc/hoogle
echo importing builtin packages
for docdir in ${ghcDocLibDir}"/"*; do
name="$(basename $docdir)"
${opts isGhcjs ''docdir="$docdir/html"''}
if [[ -d $docdir ]]; then
ln -sfn $docdir $out/share/doc/hoogle/$name
fi
done
echo importing other packages
${lib.concatMapStringsSep "\n" (el: ''
ln -sfn ${el.haddockDir} "$out/share/doc/hoogle/${el.name}"
'')
(lib.filter (el: el.haddockDir != null)
(builtins.map (p: { haddockDir = if p ? haddockDir then p.haddockDir p else null;
name = p.pname; })
docPackages))}
echo building hoogle database
hoogle generate --database $out/share/doc/hoogle/default.hoo --local=$out/share/doc/hoogle
echo building haddock index
# adapted from GHC's gen_contents_index
cd $out/share/doc/hoogle
args=
for hdfile in $(ls -1 *"/"*.haddock | grep -v '/ghc\.haddock' | sort); do
name_version=`echo "$hdfile" | sed 's#/.*##'`
args="$args --read-interface=$name_version,$hdfile"
done
${ghc}/bin/${haddockExe} --gen-index --gen-contents -o . \
-t "Haskell Hierarchical Libraries" \
-p ${prologue} \
$args
echo finishing up
mkdir -p $out/bin
substitute ${wrapper} $out/bin/hoogle \
--subst-var out --subst-var-by shell ${stdenv.shell} \
--subst-var-by hoogle ${hoogle}
chmod +x $out/bin/hoogle
'';
passthru = {
isHaskellLibrary = false; # for the filter in ./with-packages-wrapper.nix
};
meta = {
description = "A local Hoogle database";
platforms = ghc.meta.platforms;
hydraPlatforms = with lib.platforms; none;
maintainers = with lib.maintainers; [ ttuegel ];
};
}