code: private Revision uncachedHeadRevision() {
          try (RevWalk revWalk = new RevWalk(jGitRepository)) {
              final ObjectId headRevisionId = jGitRepository.resolve(R_HEADS_MASTER);
              if (headRevisionId != null) {
                  final RevCommit revCommit = revWalk.parseCommit(headRevisionId);
                  return CommitUtil.extractRevision(revCommit.getFullMessage());
              }
          } catch (CentralDogmaException e) {
              throw e;
          } catch (Exception e) {
              throw new StorageException("failed to get the current revision", e);
          }
  
          throw new StorageException("failed to determine the HEAD: " + jGitRepository.getDirectory());
      }
docs: Returns the current revision.