* A(x, y) -> B(x, x)
* Query for B(0, 0)
*/
@Test
public void testWorksSingleStepDiff() {
InferenceEnvironment infEnv = new InferenceEnvironment(null);
FusionEnvironment<?> env = new FusionEnvironment<TestAliasContext>(aliases, ctx, null, testH, infEnv, Variant.PRAGMATIC_VARIANT);
RelationshipPredicate trigger = new RelationshipPredicate(relations[0], new SpecVar[] {new SpecVar("x"), new SpecVar("y")});
List<RelEffect> eff = new LinkedList<RelEffect>();
eff.add(RelEffect.createAddEffect(relations[1], new SpecVar[] {new SpecVar("x"), new SpecVar("x")}));
InferredRel inf = new InferredRel(trigger, eff);
infEnv.addRule(inf);
RelationshipPredicate find = new RelationshipPredicate(relations[1], new SpecVar[] {new SpecVar("a"), new SpecVar("a")});
Substitution sub = new Substitution();
sub = sub.addSub(new SpecVar("a"), labels[0]);