public void GetValueCallsDataContext()
        {
            var dataContextMock = new Mock<IYateDataContext>();
            var valueMock = new Mock<IValue>();

            valueMock.Setup(dc => dc.GetValue(It.IsAny<IYateDataContext>())).Returns("*");

            var modelFunction = new ModelFunctionValue(valueMock.Object);

            modelFunction.GetValue(dataContextMock.Object);

            dataContextMock.Verify(dc => dc.GetValue(It.IsAny<string>()), Times.Once());
        }