anchor.diff:              "''${modulesPath}/testing/test-instrumentation.nix"
             ];
   
  -        boot.loader.grub.version = 2;
  +        boot.loader.grub.version = ${toString grubVersion};
  +        ${optionalString (grubVersion == 1) ''
  +          boot.loader.grub.splashImage = null;
  +        ''}
           boot.loader.grub.device = "/dev/vda";
           boot.loader.grub.extraConfig = "serial; terminal_output.serial";
           boot.initrd.kernelModules = [ "ext3" "virtio_console" ];
  
positive.code:       fileSystems = rootFS + bootFS;
      };
  
    # Rebuild the CD configuration with a little modification.
    rebuildCD =
      { inherit iso;
  
negative.code:   # a test script fragment `createPartitions', which must create
    # partitions and filesystems, and a configuration.nix fragment
    # `fileSystems'.
    testScriptFun = { createPartitions, fileSystems, testChannel, grubVersion }:
      ''
        createDisk("harddisk", 4 * 1024);
  
  