assertThat(query.columns().isEmpty(), is(true));
// FROM ...
NamedSelector selector = (NamedSelector)query.source();
assertThat(selector.name(), is(selectorName("car:Car")));
assertThat(selector.aliasOrName(), is(selectorName("car:Car")));
assertThat(selector.alias(), is(nullValue()));
// WHERE ...
DescendantNode desc = isDescendantNodeCriteria(query.constraint());
assertThat(desc.getSelectorName(), is("car:Car"));
assertThat(desc.getAncestorPath(), is("/foo/bar[2]"));
}