haskell.nix/package-set.nix
Moritz Angermann 8ee6fcfba7
Rename pkg-def-overlays to pkg-def-extras (#79)
* Rename pkg-def-overlays to pkg-def-extras

Fixes #75
2019-03-15 11:10:57 +08:00

89 lines
3.4 KiB
Nix

let f = { hackage, pkgs, pkg-def, pkg-def-extras ? [], modules ? [] }: let
buildModules = f { inherit hackage pkg-def pkg-def-extras modules; pkgs = pkgs.buildPackages; };
in pkgs.lib.evalModules {
modules = modules ++ [
({ lib, ... }: {
# Provide all modules with haskellLib, pkgs, and pkgconfPkgs arguments
_module.args = {
# this is *not* the hasekllLib from nixpkgs; it is rather our own
# library from haskell.nix
haskellLib = let hl = import ./lib { inherit lib; haskellLib = hl; }; in hl;
# The package descriptions depend on pkgs, which are used to resolve system package dependencies
# as well as pkgconfPkgs, which are used to resolve pkgconfig name to nixpkgs names. We simply
# augment the existing pkgs set with the specific mappings:
pkgs = pkgs // (import ./lib/system-nixpkgs-map.nix pkgs);
pkgconfPkgs = pkgs // (import ./lib/pkgconf-nixpkgs-map.nix pkgs);
inherit buildModules;
};
# Set the hackage DB for modules/hackage.nix
hackage.db = hackage;
# Set the plan for modules/plan.nix
plan.pkg-def = hackage: with builtins;
# The desugar reason.
#
# it is quite combersome to write
# (hackage: { packages.x.revision = hackage...;
# packages.y.revision = import ./foo.nix; })
# where we'd rather write:
# (hackage: { x = hackage...; })
# or
# { y = ./foo.nix; }
# As such the desugarer desugars this short hand syntax.
let desugar = extras:
let
isPath = x: builtins.typeOf x == "path";
# rewrite
# { ... }
# into
# { package = { ... }; }
inject-packages = o: if o ? "packages" then o else { packages = o; };
# rewrite
# x = pkg;
# into
# x.revision = pkg;
inject-revision = pkg: if pkg ? "revision" then pkg else { revision = pkg; };
# rewrite
# x.revision = ./some/path;
# into
# x.revision = import ./some/path;
expand-paths = pkg: if !(isPath pkg.revision) then pkg else { revision = import pkg.revision; };
# apply injection and expansion to the "packages" in extras.
in lib.mapAttrs (k: v: if k != "packages"
then v
else lib.mapAttrs (_: pkg: (expand-paths (inject-revision pkg))) v)
(inject-packages extras);
# fold any potential `pkg-def-extras`
# onto the `pkg-def`.
#
# This means you can have a base definition (e.g. stackage)
# and augment it with custom packages to your liking.
in foldl' lib.recursiveUpdate
(pkg-def hackage)
(map (p: desugar (if builtins.isFunction p then p hackage else p)) pkg-def-extras)
;
})
# Supplies metadata
./modules/cabal.nix
# Converts config.packages into config.hsPkgs
# Replace this with compat-driver.nix to use nixpkgs haskell build infra
./modules/component-driver.nix
# Converts config.hackage.db to config.hackage.configs
./modules/hackage.nix
# Converts config.hackage.configs and pkg-def to config.packages
./modules/plan.nix
# Configuration that applies to all plans
./modules/configuration-nix.nix
];
};
in f