private boolean stemming(ImmutableSDField field) {
        if (field.getStemming() != null) {
            return !field.getStemming().equals(Stemming.NONE);
        }
        if (schema.getStemming() == Stemming.NONE) return false;
        if (field.isImportedField()) return false;
        if (field.getIndex(field.getName())==null) return true;
        if (field.getIndex(field.getName()).getStemming()==null) return true;
        return !(field.getIndex(field.getName()).getStemming().equals(Stemming.NONE));
    }
Returns whether a particular command is prsent in this index info
config-model/src/main/java/com/yahoo/schema/derived/IndexInfo.java