cdfae7de48
The most trivial of all derivations. It is more useful than it looks. Can be used to bind nix expressions (e.g. test suites) to a derivation, so that `nix-build` does not crap itself. Change-Id: I61c24d8c129c9505733161207f3c30e820f5b15e Reviewed-on: https://cl.tvl.fyi/c/depot/+/665 Reviewed-by: tazjin <mail@tazj.in>
34 lines
950 B
Nix
34 lines
950 B
Nix
{ stdenv, pkgs, getBins }:
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# The empty derivation. All it does is touch $out.
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# Basically the unit value for derivations.
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#
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# In addition to simple test situations which require
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# a derivation, we set __functor, so you can call it
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# as a function and pass an attrset. The set you pass
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# is `//`-merged with the attrset before calling derivation,
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# so you can use this to add more fields.
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let
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bins = getBins pkgs.s6-portable-utils [ "s6-touch" ]
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// getBins pkgs.execline [ "importas" "exec" ];
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emptiness = {
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name = "empty-derivation";
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# TODO(Profpatsch): can we get system from tvl?
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inherit (stdenv) system;
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builder = bins.exec;
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args = [
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bins.importas "out" "out"
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bins.s6-touch "$out"
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];
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};
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in (derivation emptiness) // {
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# This allows us to call the empty derivation
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# like a function and override fields/add new fields.
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__functor = _: overrides:
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derivation (emptiness // overrides);
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}
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