public @NotNull Collection<VcsRef> getRefs() {
    return new AbstractCollection<>() {
      private final Supplier<Collection<VcsRef>> myLoadedRefs =
        Suppliers.memoize(() -> CompressedRefs.this.stream().collect(Collectors.toList()));

      @Override
      public @NotNull Iterator<VcsRef> iterator() {
        return myLoadedRefs.get().iterator();
      }

      @Override
      public int size() {
        return myLoadedRefs.get().size();
      }
    };
  }
public @NotNull Collection<VcsRef> getRefs()