@Parameterized.Parameters(name = "expect({0})")
    public static Iterable<Object[]> data() {
        return Arrays.asList(new Object[][]{
                {TraverserSet.class.getSimpleName(), (Supplier) TraverserSet::new},
                {IndexedTraverserSet.class.getSimpleName(), (Supplier) () -> new IndexedTraverserSet<String,String>(x -> x.substring(0,1))}});
    }
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/util/TraverserSetImplementationTest.java