281 lines
9.8 KiB
Nix
281 lines
9.8 KiB
Nix
let
|
|
|
|
lib = import ./default.nix;
|
|
inherit (builtins) attrNames isFunction;
|
|
|
|
in
|
|
|
|
rec {
|
|
|
|
|
|
/* `overrideDerivation drv f' takes a derivation (i.e., the result
|
|
of a call to the builtin function `derivation') and returns a new
|
|
derivation in which the attributes of the original are overridden
|
|
according to the function `f'. The function `f' is called with
|
|
the original derivation attributes.
|
|
|
|
`overrideDerivation' allows certain "ad-hoc" customisation
|
|
scenarios (e.g. in ~/.config/nixpkgs/config.nix). For instance,
|
|
if you want to "patch" the derivation returned by a package
|
|
function in Nixpkgs to build another version than what the
|
|
function itself provides, you can do something like this:
|
|
|
|
mySed = overrideDerivation pkgs.gnused (oldAttrs: {
|
|
name = "sed-4.2.2-pre";
|
|
src = fetchurl {
|
|
url = ftp://alpha.gnu.org/gnu/sed/sed-4.2.2-pre.tar.bz2;
|
|
sha256 = "11nq06d131y4wmf3drm0yk502d2xc6n5qy82cg88rb9nqd2lj41k";
|
|
};
|
|
patches = [];
|
|
});
|
|
|
|
For another application, see build-support/vm, where this
|
|
function is used to build arbitrary derivations inside a QEMU
|
|
virtual machine.
|
|
*/
|
|
overrideDerivation = drv: f:
|
|
let
|
|
newDrv = derivation (drv.drvAttrs // (f drv));
|
|
in addPassthru newDrv (
|
|
{ meta = drv.meta or {};
|
|
passthru = if drv ? passthru then drv.passthru else {};
|
|
}
|
|
//
|
|
(drv.passthru or {})
|
|
//
|
|
(if (drv ? crossDrv && drv ? nativeDrv)
|
|
then {
|
|
crossDrv = overrideDerivation drv.crossDrv f;
|
|
nativeDrv = overrideDerivation drv.nativeDrv f;
|
|
}
|
|
else { }));
|
|
|
|
|
|
# Like `makeOverridable`, but provides the function with the `self`
|
|
# argument. `f` is called with the new `self` whenever an override
|
|
# or extension is added.
|
|
makeOverridableWithSelf = f: origArgs: let
|
|
|
|
interface = {val, args, ...}: overridePackage:
|
|
(lib.optionalAttrs (builtins.isAttrs val) (val // {
|
|
extend = f: overridePackage (self: super: {
|
|
val = super.val // f self.val super.val;
|
|
});
|
|
|
|
overrideDerivation = newArgs: overridePackage (self: super: {
|
|
val = lib.overrideDerivation super.val newArgs;
|
|
});
|
|
})) // (lib.optionalAttrs (builtins.isFunction val) {
|
|
__functor = _: val;
|
|
extend = throw "extend not yet supported for functors";
|
|
overrideDerivation = throw "overrideDerivation not yet supported for functors";
|
|
}) // {
|
|
inherit overridePackage;
|
|
|
|
override = newArgs: overridePackage (self: super: {
|
|
args = super.args //
|
|
(if builtins.isFunction newArgs then newArgs super.args else newArgs);
|
|
});
|
|
};
|
|
|
|
in lib.makeExtensibleWithInterface interface (self: {
|
|
args = origArgs;
|
|
val = f self.args self.val;
|
|
});
|
|
|
|
|
|
/* `makeOverridable` takes a function from attribute set to
|
|
attribute set and injects 4 attributes which can be used to
|
|
override arguments and return values of the function.
|
|
|
|
|
|
1. `override` allows you to change what arguments were passed to
|
|
the function and acquire the new result.
|
|
|
|
nix-repl> x = {a, b}: { result = a + b; }
|
|
|
|
nix-repl> y = lib.makeOverridable x { a = 1; b = 2; }
|
|
|
|
nix-repl> y
|
|
{ override = «lambda»; overrideDerivation = «lambda»; result = 3; }
|
|
|
|
nix-repl> y.override { a = 10; }
|
|
{ override = «lambda»; overrideDerivation = «lambda»; result = 12; }
|
|
|
|
|
|
2. `extend` changes the results of the function, giving you a
|
|
view of the original result and a view of the eventual final
|
|
result. It is meant to do the same thing as
|
|
`makeExtensible`. That is, it lets you add to or change the
|
|
return value, such that previous extensions are consistent with
|
|
the final view, rather than being based on outdated
|
|
values. "Outdated" values come from the `super` argument, which
|
|
must be used when you are attempting to modify and old value. And
|
|
the final values come from the `self` argument, which recursively
|
|
refers to what all extensions combined return.
|
|
|
|
nix-repl> obj = makeOverridable (args: { }) { }
|
|
|
|
nix-repl> obj = obj.extend (self: super: { foo = "foo"; })
|
|
|
|
nix-repl> obj.foo
|
|
"foo"
|
|
|
|
nix-repl> obj = obj.extend (self: super: { foo = super.foo + " + "; bar = "bar"; foobar = self.foo + self.bar; })
|
|
|
|
nix-repl> obj
|
|
{ bar = "bar"; foo = "foo + "; foobar = "foo + bar"; ... } # Excess omitted
|
|
|
|
|
|
3. `overrideDerivation`: Please refer to "Nixpkgs Contributors
|
|
Guide" section "<pkg>.overrideDerivation" to learn about
|
|
`overrideDerivation` and caveats related to its use.
|
|
|
|
|
|
4. `overridePackage` is by far the most powerful of the four, as
|
|
it exposes a deeper structure. It provides `self` and `super`
|
|
views of both the arguments and return value of the function,
|
|
allowing you to change both in one override; you can even have
|
|
overrides for one based on overrides for the other. The type of
|
|
`self`, `super`, and the return value are all:
|
|
`{ args :: argumentsToF, val :: returnValueOfF }`
|
|
|
|
nix-repl> obj = makeOverridable ({a, b}: {inherit a b;}) {a = 1; b = 3;}
|
|
|
|
nix-repl> obj = obj.overridePackage (self: super: { args = super.args // {b = self.val.a;}; })
|
|
|
|
nix-repl> obj.b
|
|
1
|
|
|
|
nix-repl> obj = obj.overridePackage (self: super: { val = super.val // {a = self.args.a + 10;}; })
|
|
|
|
nix-repl> obj.b
|
|
11
|
|
|
|
*/
|
|
makeOverridable = fn: makeOverridableWithSelf (args: _: fn args);
|
|
|
|
|
|
/* Call the package function in the file `fn' with the required
|
|
arguments automatically. The function is called with the
|
|
arguments `args', but any missing arguments are obtained from
|
|
`autoArgs'. This function is intended to be partially
|
|
parameterised, e.g.,
|
|
|
|
callPackage = callPackageWith pkgs;
|
|
pkgs = {
|
|
libfoo = callPackage ./foo.nix { };
|
|
libbar = callPackage ./bar.nix { };
|
|
};
|
|
|
|
If the `libbar' function expects an argument named `libfoo', it is
|
|
automatically passed as an argument. Overrides or missing
|
|
arguments can be supplied in `args', e.g.
|
|
|
|
libbar = callPackage ./bar.nix {
|
|
libfoo = null;
|
|
enableX11 = true;
|
|
};
|
|
*/
|
|
callPackageWith = autoArgs: fn: args:
|
|
let
|
|
f = if builtins.isFunction fn then fn else import fn;
|
|
auto = builtins.intersectAttrs (builtins.functionArgs f) autoArgs;
|
|
in makeOverridable f (auto // args);
|
|
|
|
# Like `callPackageWith`, but provides the function with the `self`
|
|
# argument. `fn` is called with the new `self` whenever an override
|
|
# or extension is added.
|
|
callPackageWithSelfWith = autoArgs: fn: args:
|
|
let
|
|
f = if builtins.isFunction fn then fn else import fn;
|
|
auto = builtins.intersectAttrs (builtins.functionArgs f) autoArgs;
|
|
in makeOverridableWithSelf f (auto // args);
|
|
|
|
|
|
/* Like callPackage, but for a function that returns an attribute
|
|
set of derivations. The override function is added to the
|
|
individual attributes. */
|
|
callPackagesWith = autoArgs: fn: args:
|
|
let
|
|
f = if builtins.isFunction fn then fn else import fn;
|
|
auto = builtins.intersectAttrs (builtins.functionArgs f) autoArgs;
|
|
origArgs = auto // args;
|
|
pkgs = f origArgs;
|
|
mkAttrOverridable = name: pkg: makeOverridable (newArgs: (f newArgs).${name}) origArgs;
|
|
in lib.mapAttrs mkAttrOverridable pkgs;
|
|
|
|
|
|
/* Add attributes to each output of a derivation without changing
|
|
the derivation itself. */
|
|
addPassthru = drv: passthru:
|
|
let
|
|
outputs = drv.outputs or [ "out" ];
|
|
|
|
commonAttrs = drv // (builtins.listToAttrs outputsList) //
|
|
({ all = map (x: x.value) outputsList; }) // passthru;
|
|
|
|
outputToAttrListElement = outputName:
|
|
{ name = outputName;
|
|
value = commonAttrs // {
|
|
inherit (drv.${outputName}) outPath drvPath type outputName;
|
|
};
|
|
};
|
|
|
|
outputsList = map outputToAttrListElement outputs;
|
|
in commonAttrs // { outputUnspecified = true; };
|
|
|
|
|
|
/* Strip a derivation of all non-essential attributes, returning
|
|
only those needed by hydra-eval-jobs. Also strictly evaluate the
|
|
result to ensure that there are no thunks kept alive to prevent
|
|
garbage collection. */
|
|
hydraJob = drv:
|
|
let
|
|
outputs = drv.outputs or ["out"];
|
|
|
|
commonAttrs =
|
|
{ inherit (drv) name system meta; inherit outputs; }
|
|
// lib.optionalAttrs (drv._hydraAggregate or false) {
|
|
_hydraAggregate = true;
|
|
constituents = map hydraJob (lib.flatten drv.constituents);
|
|
}
|
|
// (lib.listToAttrs outputsList);
|
|
|
|
makeOutput = outputName:
|
|
let output = drv.${outputName}; in
|
|
{ name = outputName;
|
|
value = commonAttrs // {
|
|
outPath = output.outPath;
|
|
drvPath = output.drvPath;
|
|
type = "derivation";
|
|
inherit outputName;
|
|
};
|
|
};
|
|
|
|
outputsList = map makeOutput outputs;
|
|
|
|
drv' = (lib.head outputsList).value;
|
|
in lib.deepSeq drv' drv';
|
|
|
|
/* Make a set of packages with a common scope. All packages called
|
|
with the provided `callPackage' will be evaluated with the same
|
|
arguments. Any package in the set may depend on any other. The
|
|
`overrideScope' function allows subsequent modification of the package
|
|
set in a consistent way, i.e. all packages in the set will be
|
|
called with the overridden packages. The package sets may be
|
|
hierarchical: the packages in the set are called with the scope
|
|
provided by `newScope' and the set provides a `newScope' attribute
|
|
which can form the parent scope for later package sets. */
|
|
makeScope = newScope: f:
|
|
let self = f self // {
|
|
newScope = scope: newScope (self // scope);
|
|
callPackage = self.newScope {};
|
|
overrideScope = g:
|
|
makeScope newScope
|
|
(self_: let super = f self_; in super // g super self_);
|
|
packages = f;
|
|
};
|
|
in self;
|
|
|
|
}
|