@Nullable
  private static TextAttributes getTextAttributes(@NotNull final TextDiffType type,
                                                  @Nullable final Editor editor,
                                                  @NotNull BackgroundType background) {
    if (background == BackgroundType.NONE) return null;
    return new DiffTextAttributes(background, type, editor);
  }
@Nullable
  private static TextAttributes getTextAttributes(@NotNull final TextDiffType type,
                                                  @Nullable final Editor editor,
                                                  @NotNull BackgroundType background)