core/pkgs/build-support/mkshell/default.nix
2024-06-30 09:16:52 +01:00

74 lines
2 KiB
Nix

{
lib,
stdenv,
buildEnv,
}:
# A special kind of derivation that is only meant to be consumed by the
# nix-shell.
{
name ? "nix-shell",
# a list of packages to add to the shell environment
packages ? [ ],
# propagate all the inputs from the given derivations
inputsFrom ? [ ],
buildInputs ? [ ],
nativeBuildInputs ? [ ],
propagatedBuildInputs ? [ ],
propagatedNativeBuildInputs ? [ ],
...
}@attrs:
let
mergeInputs =
name:
(attrs.${name} or [ ])
++
# 1. get all `{build,nativeBuild,...}Inputs` from the elements of `inputsFrom`
# 2. since that is a list of lists, `flatten` that into a regular list
# 3. filter out of the result everything that's in `inputsFrom` itself
# this leaves actual dependencies of the derivations in `inputsFrom`, but never the derivations themselves
(lib.subtractLists inputsFrom (lib.flatten (lib.catAttrs name inputsFrom)));
rest = builtins.removeAttrs attrs [
"name"
"packages"
"inputsFrom"
"buildInputs"
"nativeBuildInputs"
"propagatedBuildInputs"
"propagatedNativeBuildInputs"
"shellHook"
];
in
stdenv.mkDerivation (
{
inherit name;
buildInputs = mergeInputs "buildInputs";
nativeBuildInputs = packages ++ (mergeInputs "nativeBuildInputs");
propagatedBuildInputs = mergeInputs "propagatedBuildInputs";
propagatedNativeBuildInputs = mergeInputs "propagatedNativeBuildInputs";
shellHook = lib.concatStringsSep "\n" (
lib.catAttrs "shellHook" (lib.reverseList inputsFrom ++ [ attrs ])
);
phases = [ "buildPhase" ];
buildPhase = ''
{ echo "------------------------------------------------------------";
echo " WARNING: the existence of this path is not guaranteed.";
echo " It is an internal implementation detail for pkgs.mkShell.";
echo "------------------------------------------------------------";
echo;
# Record all build inputs as runtime dependencies
export;
} >> "$out"
'';
preferLocalBuild = true;
}
// rest
)