Right now I have this:
```
} else if (res == null) {
                    DocIdSetIterator it = clause.docIdSet.iterator();
                    if (it != null) {
                        hasNonEmptyShouldClause = true;
                        res = new FixedBitSet(reader.maxDoc());
                        res.or(it);
                    }
                } else {
                    DocIdSetIterator it = clause.docIdSet.iterator();
                    if (it != null) {
                        hasNonEmptyShouldClause = true;
                        res.or(it);
                    }
                }
```

B/c the in the else clause I know `res` is there I don't need to check for it any more, so it feels a bit of the extract the logic and put it into a static method?