public void testLazy() throws Exception {
    eval.setEvaluationVisitor(new LazyTestVisitorMock());
    eval.registerPredefined();

    Object val = eval.eval("if(12<3,'mama','papa')");
    assertEquals("papa", val);
  }
  public void testFact() throws Exception {
    Object val = eval.eval("fact(6)");
    assertEquals(720L, val);

    eval.setVariable("v", -100.);
    val = eval.eval("abs(${v})");
    assertEquals(100., val);

    val = eval.eval("round(112.6)");
    assertEquals(113L, val);
  }
 @Override
 protected void setUp() throws Exception {
   super.setUp();
   eval = new ExpressionEval();
   eval.registerPredefined();
 }