code: func (s *GitScanner) ScanRefRange(left, right string, cb GitScannerFoundPointer) error {
  	callback, err := firstGitScannerCallback(cb, s.FoundPointer)
  	if err != nil {
  		return err
  	}
  
  	opts := s.opts(ScanRefsMode)
  	opts.SkipDeletedBlobs = false
  	return scanLeftRightToChan(s, callback, left, right, opts)
  }
docs: // ScanRefRange scans through all commits from the given left and right refs,
  // including git objects that have been modified or deleted.