private @NotNull Collection<Hash> filterUnnamedHeads() {
      Collection<Hash> branchWithHashes = myRepository.getBranches().get(myCurrentBranchName);
      String currentHead = myRepository.getCurrentRevision();
      if (branchWithHashes == null || currentHead == null || myRepository.getState() != Repository.State.NORMAL) {
        // repository is fresh or branch is fresh or complex state
        return Collections.emptySet();
      }
      else {
        Collection<Hash> bookmarkHashes = ContainerUtil.map(myRepository.getBookmarks(), info -> info.getHash());
        branchWithHashes.removeAll(bookmarkHashes);
        branchWithHashes.remove(HashImpl.build(currentHead));
      }
      return branchWithHashes;
    }
private @NotNull Collection<Hash> filterUnnamedHeads()