diff --git a/nix/drvSeqL/default.nix b/nix/drvSeqL/default.nix new file mode 100644 index 000000000..3339289b3 --- /dev/null +++ b/nix/drvSeqL/default.nix @@ -0,0 +1,43 @@ +{ depot, lib, pkgs, ... }: + +let + + inherit (depot.nix.yants) + defun + list + drv + ; + + /* Realize drvDeps, then return drvOut if that succeds. + * This can be used to make drvOut depend on the + * build success of all drvDeps without making each drvDep + * a dependency of drvOut. + * => drvOut is not rebuilt if drvDep changes + */ + drvSeqL = defun [ (list drv) drv drv ] + (drvDeps: drvOut: + let + drvOutOutputs = drvOut.outputs or ["out"]; + in + pkgs.runCommandLocal drvOut.name { + # we inherit all attributes in order to replicate + # the original derivation as much as possible + outputs = drvOutOutputs; + passthru = drvOut.drvAttrs; + # depend on drvDeps (by putting it in builder context) + inherit drvDeps; + } + # the outputs of the original derivation are replicated + # by creating a symlink to the old output path + (lib.concatMapStrings (output: '' + target=${lib.escapeShellArg drvOut.${output}} + # if the target is already a symlink, follow it until it’s not; + # this is done to prevent too many dereferences + target=$(readlink -e "$target") + # link to the output + ln -s "$target" "${"$"}${output}" + '') drvOutOutputs)); + +in { + __functor = _: drvSeqL; +}