crane/checks/compilesFresh.nix

{ buildDepsOnly
, jq
}:

expectedArg: mkDrv: args:
let
  runCargoAndCheckFreshness = cmd: extra:
    let
      expected =
        if builtins.isAttrs expectedArg then
          expectedArg.${cmd} or ""
        else
          expectedArg;
    in
    ''
      cargo ${cmd} \
        --release \
        --message-format json-diagnostic-short \
        ${extra} \
        ${args.cargoExtraArgs or ""} >${cmd}out

      filter='select(.reason == "compiler-artifact" and .fresh != true) | .target.name'
      builtTargets="$(jq -r "$filter" <${cmd}out | sort -u)"

      # Make sure only the crate needed building
      if [[ "${expected}" != "$builtTargets" ]]; then
        echo for command ${cmd}
        echo expected \""${expected}"\"
        echo but got  \""$builtTargets"\"
        false
      fi
    '';
in
mkDrv (args // {
  doInstallCargoArtifacts = false;

  # NB: explicit call here so that the buildDepsOnly call
  # doesn't inherit our build commands
  cargoArtifacts = buildDepsOnly args;

  nativeBuildInputs = [ jq ];

  buildPhase = ''
    runHook preBuild

    ${runCargoAndCheckFreshness "check" ""}
    ${runCargoAndCheckFreshness "build" ""}

    runHook postBuild
  '';

  checkPhase = ''
    runHook preCheck

    ${runCargoAndCheckFreshness "test" "--no-run"}

    runHook postCheck
  '';

  installPhase = ''
    touch $out
  '';
})