private static List<FieldPart> initFieldParts(List<FieldPart> newFieldParts) {
        if (newFieldParts == null)
            newFieldParts = new ArrayList<>();
        return newFieldParts;
    }
This converts the backend binary highlighting of each item in an array of string field,
and creates a new field that replaces the original.
container-search/src/main/java/com/yahoo/prelude/searcher/JuniperSearcher.java