neovim: check for pnames when asserting if two treesitters are installed (#512097)

            paths = allGrammars;

          };

          allAndOptPluginNames = map (plugin: plugin.pname) (allPlugins ++ opt);

          packdirStart = vimFarm "pack/${packageName}/start" "packdir-start" (

            if allGrammars != [ ] then allPlugins ++ [ allGrammarsSymlinked ] else allPlugins

          );

        assert

          (

            builtins.elem vimPlugins.nvim-treesitter (opt ++ allPlugins)

            && builtins.elem vimPlugins.nvim-treesitter-legacy (opt ++ allPlugins)

            builtins.elem "nvim-treesitter" allAndOptPluginNames

            && builtins.elem "nvim-treesitter-legacy" allAndOptPluginNames

          )

          -> throw "You cannot include two different versions of nvim-treesitter, perhaps you included a legacy plugin together with a new one?";