private static @Nullable Map<TodoIndexEntry, Integer> calcTodoMap(@NotNull Project project, @NotNull LightVirtualFile file) {
    CharSequence content = file.getContent();
    if (StringUtil.isEmpty(content)) return null;
    TodoIndex extension = FileBasedIndexExtension.EXTENSION_POINT_NAME.findExtension(TodoIndex.class);
    if (extension == null) return null;
    FileContent fc = FileContentImpl.createByText(file, content, project);
    Map<Integer, Map<TodoIndexEntry, Integer>> data = extension.getIndexer().map(fc);
    return ContainerUtil.getFirstItem(data.values());
  }
private static @Nullable Map<TodoIndexEntry, Integer> calcTodoMap(@NotNull Project project, @NotNull LightVirtualFile file)