nixpkgs/pkgs/development/compilers/elm/default.nix
2018-11-21 10:57:11 +00:00

97 lines
3.3 KiB
Nix

{ lib, stdenv, buildEnv
, haskell, nodejs
, fetchurl, fetchpatch, makeWrapper, git }:
# To update:
# 1) Modify ./update.sh and run it
# 2) to generate versions.dat:
# 2.1) git clone https://github.com/elm/compiler.git
# 2.2) cd compiler
# 2.3) cabal2nix --shell . | sed 's/"default",/"ghc822",/' > shell.nix
# 2.4) nix-shell
# 2.5) mkdir .elm
# 2.6) export ELM_HOME=$(pwd)/.elm
# 2.7) cabal build
# 2.8) cp .elm/0.19.0/package/versions.dat ...
# 3) generate a template for elm-elm.nix with:
# (
# echo "{";
# jq '.dependencies | .direct, .indirect | to_entries | .[] | { (.key) : { version : .value, sha256: "" } } ' \
# < ui/browser/elm.json \
# | sed 's/:/ =/' \
# | sed 's/^[{}]//' \
# | sed -E 's/(["}]),?$/\1;/' \
# | sed -E 's/"(version|sha256)"/\1/' \
# | grep -v '^$';
# echo "}"
# )
#
# ... then fill in the sha256s
# 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
fetchElmDeps = import ./fetchElmDeps.nix { inherit stdenv lib fetchurl; };
hsPkgs = haskell.packages.ghc822.override {
overrides = self: super: with haskell.lib;
let elmPkgs = {
elm = overrideCabal (self.callPackage ./packages/elm.nix { }) (drv: {
# sadly with parallelism most of the time breaks compilation
enableParallelBuilding = false;
preConfigure = fetchElmDeps {
elmPackages = (import ./packages/elm-elm.nix);
versionsDat = ./versions.dat;
};
buildTools = drv.buildTools or [] ++ [ makeWrapper ];
patches = [
(fetchpatch {
url = "https://github.com/elm/compiler/pull/1784/commits/78d2d8eab310552b1b877a3e90e1e57e7a09ddec.patch";
sha256 = "0vdhk16xqm2hxw12s1b91a0bmi8w4wsxc086qlzglgnjxrl5b3w4";
})
];
postInstall = ''
wrapProgram $out/bin/elm \
--prefix PATH ':' ${lib.makeBinPath [ nodejs ]}
'';
});
/*
The elm-format expression is updated via a script in the https://github.com/avh4/elm-format repo:
`pacakge/nix/build.sh`
*/
elm-format = self.callPackage ./packages/elm-format.nix {};
inherit fetchElmDeps;
};
in elmPkgs // {
inherit elmPkgs;
elmVersion = elmPkgs.elm.version;
# Needed for elm-format
indents = self.callPackage ./packages/indents.nix {};
tasty-quickcheck = self.callPackage ./packages/tasty-quickcheck.nix {};
};
};
in hsPkgs.elmPkgs