code: func (f *sendReceiveFolder) pullScannerRoutine(scanChan <-chan string) {
  	toBeScanned := make(map[string]struct{})
  
  	for path := range scanChan {
  		toBeScanned[path] = struct{}{}
  	}
  
  	if len(toBeScanned) != 0 {
  		scanList := make([]string, 0, len(toBeScanned))
  		for path := range toBeScanned {
  			l.Debugln(f, "scheduling scan after pulling for", path)
  			scanList = append(scanList, path)
  		}
  		f.Scan(scanList)
  	}
  }
docs: // pullScannerRoutine aggregates paths to be scanned after pulling. The scan is
  // scheduled once when scanChan is closed (scanning can not happen during pulling).