public void CreateFunction_functionName_ShouldReturnIRfcFunction() { var functionName = "TEST"; var connection = new RfcConnection(_interopMock.Object, RfcConfigurationOption); RfcErrorInfo errorInfo; _interopMock .Setup(x => x.GetFunctionDesc(It.IsAny <IntPtr>(), It.IsAny <string>(), out errorInfo)) .Returns(FunctionDescriptionHandle); _interopMock .Setup(x => x.CreateFunction(It.IsAny <IntPtr>(), out errorInfo)) .Returns(FunctionHandle); IRfcFunction function = connection.CreateFunction(functionName); function.Should().NotBeNull(); }