tjh.dev
1# Install not only the Hoogle library and executable, but also a local Hoogle
2# database which provides "Source" links to all specified 'packages' -- or the
3# current Haskell Platform if no custom package set is provided.
4
5{ lib, stdenv, buildPackages, haskellPackages
6, writeText
7}:
8
9# This argument is a function which selects a list of Haskell packages from any
10# passed Haskell package set.
11#
12# Example:
13# (hpkgs: [ hpkgs.mtl hpkgs.lens ])
14selectPackages:
15
16let
17 inherit (haskellPackages) ghc hoogle;
18 packages = selectPackages haskellPackages;
19
20 wrapper = ./hoogle-local-wrapper.sh;
21 isGhcjs = ghc.isGhcjs or false;
22 opts = lib.optionalString;
23 haddockExe =
24 if !isGhcjs
25 then "haddock"
26 else "haddock-ghcjs";
27 ghcDocLibDir =
28 if !isGhcjs
29 then ghc.doc + "/share/doc/ghc*/html/libraries"
30 else ghc + "/doc/lib";
31 # On GHCJS, use a stripped down version of GHC's prologue.txt
32 prologue =
33 if !isGhcjs
34 then "${ghcDocLibDir}/prologue.txt"
35 else writeText "ghcjs-prologue.txt" ''
36 This index includes documentation for many Haskell modules.
37 '';
38
39 docPackages = lib.closePropagation
40 # we grab the doc outputs
41 (map (lib.getOutput "doc") packages);
42
43in
44buildPackages.stdenv.mkDerivation {
45 name = "hoogle-with-packages";
46 buildInputs = [ghc hoogle];
47
48 # compiling databases takes less time than copying the results
49 # between machines.
50 preferLocalBuild = true;
51
52 # we still allow substitutes because a database is relatively small and if it
53 # is already built downloading is probably faster. The substitution will only
54 # trigger for users who have already cached the database on a substituter and
55 # thus probably intend to substitute it.
56 allowSubstitutes = true;
57
58 inherit docPackages;
59
60 passAsFile = ["buildCommand"];
61
62 buildCommand = ''
63 ${let # Filter out nulls here to work around https://github.com/NixOS/nixpkgs/issues/82245
64 # If we don't then grabbing `p.name` here will fail.
65 packages' = lib.filter (p: p != null) packages;
66 in lib.optionalString (packages' != [] -> docPackages == [])
67 ("echo WARNING: localHoogle package list empty, even though"
68 + " the following were specified: "
69 + lib.concatMapStringsSep ", " (p: p.name) packages')}
70 mkdir -p $out/share/doc/hoogle
71
72 echo importing builtin packages
73 for docdir in ${ghcDocLibDir}"/"*; do
74 name="$(basename $docdir)"
75 ${opts isGhcjs ''docdir="$docdir/html"''}
76 if [[ -d $docdir ]]; then
77 ln -sfn $docdir $out/share/doc/hoogle/$name
78 fi
79 done
80
81 echo importing other packages
82 ${lib.concatMapStringsSep "\n" (el: ''
83 ln -sfn ${el.haddockDir} "$out/share/doc/hoogle/${el.name}"
84 '')
85 (lib.filter (el: el.haddockDir != null)
86 (builtins.map (p: { haddockDir = if p ? haddockDir then p.haddockDir p else null;
87 name = p.pname; })
88 docPackages))}
89
90 echo building hoogle database
91 hoogle generate --database $out/share/doc/hoogle/default.hoo --local=$out/share/doc/hoogle
92
93 echo building haddock index
94 # adapted from GHC's gen_contents_index
95 cd $out/share/doc/hoogle
96
97 args=
98 for hdfile in $(ls -1 *"/"*.haddock | grep -v '/ghc\.haddock' | sort); do
99 name_version=`echo "$hdfile" | sed 's#/.*##'`
100 args="$args --read-interface=$name_version,$hdfile"
101 done
102
103 ${ghc}/bin/${haddockExe} --gen-index --gen-contents -o . \
104 -t "Haskell Hierarchical Libraries" \
105 -p ${prologue} \
106 $args
107
108 echo finishing up
109 mkdir -p $out/bin
110 substitute ${wrapper} $out/bin/hoogle \
111 --subst-var out --subst-var-by shell ${stdenv.shell} \
112 --subst-var-by hoogle ${hoogle}
113 chmod +x $out/bin/hoogle
114 '';
115
116 passthru = {
117 isHaskellLibrary = false; # for the filter in ./with-packages-wrapper.nix
118 };
119
120 meta = {
121 description = "A local Hoogle database";
122 platforms = ghc.meta.platforms;
123 hydraPlatforms = with lib.platforms; none;
124 maintainers = with lib.maintainers; [ ttuegel ];
125 };
126}