code: private boolean twoPhaseCurrentDocMatches() throws IOException {
      if (docId != subSpans.docID()) {
        reset();
        docId = subSpans.docID();
        IndexDoc doc = mtasCodecInfo.getDoc(field, docId);
        if (doc != null) {
          minPosition = doc.minPosition;
          maxPosition = doc.maxPosition;
        } else {
          minPosition = NO_MORE_POSITIONS;
          maxPosition = NO_MORE_POSITIONS;
        }
      }
      if (docId == NO_MORE_DOCS) {
        return false;
      } else {
        return goToNextStartPosition();
      }
    }
docs: Two phase current doc matches.
  
  @return true, if successful
  @throws IOException Signals that an I/O exception has occurred.