public void OnEvaluate_Error()
        {
            var evaluator = new HeaderEvaluator();
            var header    = new Header();

            try
            {
                var actual = evaluator.Evaluate("${call1.response.header.key_str}", CreateTestResult("call1", header));
            }
            catch (Exception ex)
            {
                Assert.AreEqual("Depedency ${call1.response.header.key_str} not found", ex.Message);
                return;
            }
            Assert.Fail();
        }
        public void OnEvaluate_ShouldFindResult()
        {
            var evaluator = new HeaderEvaluator();
            var header    = new Header();

            header.Add(new JsonString("key_str", "value"));
            header.Add(new JsonLong("key_int", 20));


            var actual = evaluator.Evaluate("${call1.response.header.key_str}", CreateTestResult("call1", header));

            Assert.AreEqual("value", actual);

            actual = evaluator.Evaluate("${call1.response.header.key_int}", CreateTestResult("call1", header));
            Assert.AreEqual(20, long.Parse(actual));
        }