dev/nixpkgs
1
0
Fork 0
Code Issues Pull Requests Actions 2 Packages Projects Releases Wiki Activity

haskell: preserve overrideScope on override

Browse Source 
We want code such as `(pkg.override {}).overrideScope (self: super: {})` to
work. This didn't work before, since `override` will call the original package
again, and the attribute `overideScope`, which `callPackageWithScope` added,
wasn't added again. The fix for this is to modify the package function itself
to include the `callPackageWithScope` attribute, so it'll be re-added whenever
the function is overriden for with arguments.

There is a small problem here though: since callPackage uses some magic
(`builtins.functionArgs`) to determine the auto-arguments of a function, we
can't just write `callPackageWith scope drvScope`, since
`builtins.functionArgs drvScope` will be `{}`. To fix this, we implement our own
`callPackageWith`.

Fixes https://github.com/NixOS/nixpkgs/issues/7953.
Closes https://github.com/NixOS/nixpkgs/pull/9336.
This commit is contained in:
Benno Fünfstück 2015-08-19 11:23:28 +02:00 committed by Peter Simons
parent 9b74549c0b
commit 731e0fa742
1 changed files with 17 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
pkgs/development/haskell-modules/make-package-set.nix
View File

@ -44,9 +44,23 @@ self: let
mkDerivation = makeOverridable mkDerivationImpl;
callPackageWithScope = scope: drv: args: (stdenv.lib.callPackageWith scope drv args) // {
overrideScope = f: callPackageWithScope (mkScope (fix' (extends f scope.__unfix__))) drv args;
};
callPackageWithScope = scope: fn: manualArgs:
let
# this code is copied from callPackage in lib/customisation.nix
#
# we cannot use `callPackage` here because we want to call `makeOverridable`
# on `drvScope` (we cannot add `overrideScope` after calling `callPackage` because then it is
# lost on `.override`) but determine the auto-args based on `drv` (the problem here
# is that nix has no way to "passthrough" args while preserving the reflection
# info that callPackage uses to determine the arguments).
drv = if builtins.isFunction fn then fn else import fn;
auto = builtins.intersectAttrs (builtins.functionArgs drv) scope;
drvScope = allArgs: drv allArgs // {
overrideScope = f:
let newScope = mkScope (fix' (extends f scope.__unfix__));
in callPackageWithScope newScope drv manualArgs;
};
in stdenv.lib.makeOverridable drvScope (auto // manualArgs);
mkScope = scope: pkgs // pkgs.xorg // pkgs.gnome2 // scope;
defaultScope = mkScope self;