anchor.diff:      name = "vim-with-vim-addon-nix";
       vimrcConfig.packages.myVimPackage.start = with vimPlugins; [ vim-nix ];
     };
  +
  +  # only neovim makes use of `requiredPlugins`, test this here
  +  test_nvim_with_vim_nix_using_pathogen = neovim.override {
  +    configure.pathogen.pluginNames = [ "vim-nix" ];
  +  };
   }
  
positive.code: {stdenv, vim, vimPlugins, vim_configurable, buildEnv, writeText, writeScriptBin
  , nix-prefetch-hg, nix-prefetch-git }:
  
  /*
  
negative.code:                      if vam != null && vam ? knownPlugins then vam.knownPlugins else
                       if pathogen != null && pathogen ? knownPlugins then pathogen.knownPlugins else
                       vimPlugins;
        pathogenPlugins = findDependenciesRecursively knownPlugins pathogen.pluginNames;
        vamPlugins = findDependenciesRecursively knownPlugins (lib.concatMap vamDictToNames vam.pluginDictionaries);
        nonNativePlugins = (lib.optionals (pathogen != null) pathogenPlugins)
                        ++ (lib.optionals (vam != null) vamPlugins)
                        ++ (lib.optionals (plug != null) plug.plugins);
        nativePluginsConfigs = lib.attrsets.attrValues packages;
        nativePlugins = lib.concatMap ({start?[], opt?[], knownPlugins?vimPlugins}: start++opt) nativePluginsConfigs;
      in
  