private static void putActionsForReferences(@NotNull VcsLogDataPack pack,
                                              @NotNull List<? extends RefGroup> references,
                                              @NotNull Groups actions) {
    for (RefGroup refGroup : references) {
      if (refGroup instanceof SingletonRefGroup) {
        VcsRef ref = ((SingletonRefGroup)refGroup).getRef();
        if (isFavorite(pack, ref)) {
          append(actions.favoriteGroups, refGroup.getName(), ref);
        }
        else {
          append(actions.singletonGroups, refGroup.getName(), ref);
        }
      }
      else {
        TreeMap<String, TreeMap<String, Collection<VcsRef>>> groups =
          refGroup.isExpanded() ? actions.expandedGroups : actions.collapsedGroups;
        TreeMap<String, Collection<VcsRef>> groupActions =
          groups.computeIfAbsent(refGroup.getName(), key -> new TreeMap<>(NaturalComparator.INSTANCE));
        for (VcsRef ref : refGroup.getRefs()) {
          if (isFavorite(pack, ref)) {
            append(actions.favoriteGroups, ref.getName(), ref);
          }
          append(groupActions, ref.getName(), ref);
        }
      }
    }
  }
private static void putActionsForReferences(@NotNull VcsLogDataPack pack,
                                              @NotNull List<? extends RefGroup> references,
                                              @NotNull Groups actions)