easy-dhall-nix/build.nix

{ pkgs, release }:

{ simpleName, binNames, attrName }:

let
  release = import ./release.nix;
in

pkgs.stdenv.mkDerivation rec {
  name = simpleName;

  src = if pkgs.stdenv.isDarwin
  then pkgs.fetchurl {
    url = release.${"${attrName}-darwin"}.url;
    sha256 = release.${"${attrName}-darwin"}.hash;
  }
  else pkgs.fetchurl {
    url = release.${"${attrName}-linux"}.url;
    sha256 = release.${"${attrName}-linux"}.hash;
  };

  nativeBuildInputs = [ pkgs.installShellFiles ];

  passthru.binNames = binNames;

  sourceRoot = ".";

  installPhase = ''
    mkdir -p $out/bin

    ${pkgs.lib.concatMapStringsSep "\n" (binName: ''
        binPath="$out/bin/${binName}"
        install -D -m555 -T "bin/${binName}" "$binPath"
        rm "bin/${binName}"

        "$binPath" --bash-completion-script "$binPath" > "${binName}.bash"
        installShellCompletion --bash "${binName}.bash"
        rm "${binName}.bash"
        "$binPath" --zsh-completion-script "$binPath" > "${binName}.zsh"
        installShellCompletion --zsh "${binName}.zsh"
        rm "${binName}.zsh"
        "$binPath" --fish-completion-script "$binPath" > "${binName}.fish"
        installShellCompletion --fish "${binName}.fish"
        rm "${binName}.fish"
      '') binNames}

    rmdir bin

    # a bit hacky, but sourceRoot unfortunately unpacks to the runtime build dir
    rm env-vars .sandbox.sb || true

    # check that we didn’t forget any files (maybe a new binary was added)
    if [ ! -z "$(${pkgs.lr}/bin/lr -1 -t 'depth == 1' .)" ]; then
      echo "still some files remaining!" >&2
      ${pkgs.lr}/bin/lr .
      exit 1
    fi

  '';
}