public void TestGetStringPrivateData()
        {
            ChaincodeStub stub  = new ChaincodeStub("myc", "txId", handler.Object, new List <ByteString>(), null);
            string        value = "TEST";

            handler.Setup(a => a.GetStateAsync("myc", "txId", "testcoll", "key", token)).ReturnsAsync(ByteString.CopyFromUtf8(value));
            Assert.AreEqual(stub.GetPrivateDataUTF8("testcoll", "key"), value);
        }