} else if (mergingFields != null) {
// document isn't deleted, check if any of the fields have an update to it
int newDoc = -1;
for (int idx = 0; idx < mergingFields.length; idx++) {
UpdatesIterator updatesIter = updatesIters[idx];
if (updatesIter.doc() == j) { // document has an update
if (mergedDeletesAndUpdates == null) {
mergedDeletesAndUpdates = readerPool.get(merge.info, true);
docMap = getDocMap(merge, mergeState);
}
if (newDoc == -1) { // map once per all field updates, but only if there are any updates