public void TestAddition()
{
//Arrange
Calculations op = new Calculations();
op.leftOperand = 30;
op.rightOperand = 30;
op.Operator = "+";
op.result = 0;
//Act
ViewResult vr = (ViewResult)controller.DoCalculation(op);
Calculations model = (Calculations)vr.Model;
//Assert
Assert.Equal(60, model.result);
}