FilteredStreamRulePredicate empty does not return true for isEmpty

[snicoll]

I am initializing a predicate to empty to build a list of OR predicates.

I've noticed that applying or on such a predicate with anything leads to the following predicate:

 OR mypredicate

(notice the space before the OR).

I've tried to workaround this by creating the following method:

private static FilteredStreamRulePredicate or(FilteredStreamRulePredicate left, FilteredStreamRulePredicate right) {
    if (left == null || left.isEmpty()) {
        return right;
    }
    return left.or(right);
}

That turned out to not work as even if left is FilteredStreamRulePredicate.empty(), isEmpty returns false.

I am happy to contribute a PR. Besides contributing a fix for the isEmpty check, it would be nice to also fix the composition so that it doesn't apply an operator between two predicates if one of them is empty.

[redouane59]

Hello,

Feel free to submit a pull request yes :)
This feature was also added by a contributor a few months ago.