nixpkgs/pkgs/development/compilers/elm/default.nix
2018-08-26 23:20:41 +01:00

103 lines
3.6 KiB
Nix

{ lib, stdenv, buildEnv, haskell, nodejs, fetchurl, makeWrapper, git }:
# To update:
# 1) Modify ./update.sh and run it
# 2) XXX: generate packages/elm-elm.nix
# 3) XXX: versions.dat
# Notes:
# the elm binary embeds a piece of pre-compiled elm code, used by 'elm
# reactor'. this means that the build process for 'elm' effectively
# executes 'elm make'. that in turn expects to retrieve the elm
# dependencies of that code (elm/core, etc.) from
# package.elm-lang.org, as well as a cached bit of metadata
# (versions.dat).
# the makeDotElm function lets us retrieve these dependencies in the
# standard nix way. we have to copy them in (rather than symlink) and
# make them writable because the elm compiler writes other .dat files
# alongside the source code. versions.dat was produced during an
# impure build of this same code; the build complains that it can't
# update this cache, but continues past that warning.
# finally, we set ELM_HOME to point to these pre-fetched artifacts so
# that the default of ~/.elm isn't used.
let
makeDotElm = ver: deps:
let versionsDat = ./versions.dat;
cmds = lib.mapAttrsToList (name: info: let
pkg = stdenv.mkDerivation {
name = lib.replaceChars ["/"] ["-"] name + "-${info.version}";
src = fetchurl {
url = "https://github.com/${name}/archive/${info.version}.tar.gz";
meta.homepage = "https://github.com/${name}/";
inherit (info) sha256;
};
phases = [ "unpackPhase" "installPhase" ];
installPhase = ''
mkdir -p $out
cp -r * $out
'';
};
in ''
mkdir -p .elm/${ver}/package/${name}
cp -R ${pkg} .elm/${ver}/package/${name}/${info.version}
'') deps;
in (lib.concatStrings cmds) + ''
mkdir -p .elm/${ver}/package;
cp ${versionsDat} .elm/${ver}/package/versions.dat;
chmod -R +w .elm
'';
hsPkgs = haskell.packages.ghc822.override {
overrides = self: super: with haskell.lib;
let elmPkgs = {
elm = overrideCabal (self.callPackage ./packages/elm.nix { }) (attrs: {
# sadly with parallelism most of the time breaks compilation
enableParallelBuilding = false;
preConfigure = ''
export ELM_HOME=`pwd`/.elm
'' + (makeDotElm "0.19.0" (import ./packages/elm-elm.nix));
});
/*
This is not a core Elm package, and it's hosted on GitHub.
To update, run:
cabal2nix --jailbreak --revision refs/tags/foo http://github.com/avh4/elm-format > packages/elm-format.nix
where foo is a tag for a new version, for example "0.8.0".
*/
elm-format = overrideCabal (self.callPackage ./packages/elm-format.nix { }) (drv: {
# https://github.com/avh4/elm-format/issues/529
patchPhase = ''
cat >Setup.hs <<EOF
import Distribution.Simple
main = defaultMain
EOF
sed -i '/Build_elm_format/d' elm-format.cabal
sed -i 's/Build_elm_format.gitDescribe/""/' src/ElmFormat/Version.hs
sed -i '/Build_elm_format/d' src/ElmFormat/Version.hs
'';
});
};
in elmPkgs // {
inherit elmPkgs;
elmVersion = elmPkgs.elm.version;
# Needed for elm-format
indents = self.callPackage ./packages/indents.nix {};
};
};
in hsPkgs.elmPkgs