OrFilter.getRight() returns an AndFilter for three or more sub-filters

[vharseko]

OrFilter.getRight() returns an AndFilter when the filter holds three or more sub-filters (OrFilter.java:77-87):

if (subFilters.size() > 2) {
    final LinkedList<Filter> right = new LinkedList<Filter>(subFilters);
    right.removeFirst();
    return new AndFilter(right);   // should be new OrFilter(right)
}

FilterBuilder.or(Collection) and FilterBuilder.or(Filter...) build exactly such a flat OrFilter (FilterBuilder.java:456-479). Code that walks it through getLeft()/getRight() therefore turns or(a, b, c) into OR(a, AND(b, c)). An object that matches only b or only c then stops matching. OrFilter.accept(ConnectorObject) iterates over the flat list and is not affected.

Callers that walk getLeft()/getRight():

• ObjectNormalizerFacade.normalizeFilter (the visitOrFilter branch): the normalized filter that SearchImpl passes to the connector already has the wrong structure.
• AbstractFilterTranslator: normalizeNot, negate, simplifyAndDistribute and translateInternal, which every connector based on the translator uses.
• FilterHandlers.CompositeFilterHandler.serialize: the filter is sent to a remote connector server as left/right, so the server receives OR(a, AND(b, c)).
• MapFilterVisitor.visitOrFilter (groovy connector): scripts receive the same wrong tree.

This bug predates #145. It was found during that PR's review: #145 (review)

Fix: one line in OrFilter.getRight(), return new OrFilter(right);. It corrects every caller above at once.

Reproduction: build a, b and c as EqualsFilters on different values, and an obj that matches only c.

• FilterBuilder.or(a, b, c).accept(obj) returns true.
• new OrFilter(f.getLeft(), f.getRight()).accept(obj) returns false, where f = FilterBuilder.or(a, b, c). The same holds for normalizeFilter(f).accept(obj).