public void ShouldApplyOperatorRaiseExceptionWhenStackEmpty()
{
CalculatorContainer container = new CalculatorContainer();
CalculatorExecutor executor = new CalculatorExecutor();
container.PushItem(5);
InvalidOperationException ex = Assert.Throws <InvalidOperationException>(() => executor.ApplyOperator(container, "+"));
Assert.That(ex.Message, Is.EqualTo("The stack must have at least two items to apply an operator"));
}
public void ShouldApplyOperatorRaiseExceptionWhenOperatorInvalid()
{
CalculatorContainer container = new CalculatorContainer();
CalculatorExecutor executor = new CalculatorExecutor();
container.PushItem(5);
container.PushItem(5);
container.PushItem(5);
InvalidOperationException ex = Assert.Throws <InvalidOperationException>(() => executor.ApplyOperator(container, ":"));
Assert.That(ex.Message, Is.EqualTo("The symbol ':' is not recognised as a valid operator. Accepted operators are: (+, -, *, /)"));
}
public void ShouldApplyOperatorSuccefully()
{
CalculatorContainer container = new CalculatorContainer();
CalculatorExecutor executor = new CalculatorExecutor();
container.PushItem(5);
container.PushItem(7);
container.PushItem(8);
executor.ApplyOperator(container, "+");
Assert.AreEqual("5;15", container.PrettyDisplay());
container.PushItem(10);
executor.ApplyOperator(container, "-");
Assert.AreEqual("5;-5", container.PrettyDisplay());
executor.ApplyOperator(container, "*");
Assert.AreEqual("-25", container.PrettyDisplay());
}
public void DividingByZeroShouldBeHandledByCode()
{
var calculatorItems = new CalculatorItems
{
firstNumberText = "1",
secondNumberText = "0",
operationText = "/"
};
try
{
var returnedCalculatorItems = new CalculatorExecutor(calculatorItems).Run();
}
catch (Exception exception)
{
Assert.IsTrue(exception.Message.Contains("0-val"));
}
}
public void AddingTwoNumbersShouldReturnCorrectResult()
{
var calculatorItems = new CalculatorItems
{
firstNumberText = "33333.3333",
secondNumberText = "77777.7777",
operationText = "+"
};
var expectedResult = Convert.ToDouble(calculatorItems.firstNumberText) +
Convert.ToDouble(calculatorItems.secondNumberText);
try
{
var returnedCalculatorItems = new CalculatorExecutor(calculatorItems).Run();
Assert.IsTrue(Math.Abs(returnedCalculatorItems.result - expectedResult) <= double.Epsilon);
}
catch (Exception exception)
{
throw new Exception(exception.Message);
}
}
public void Positive(string expression, int expectedResult)
{
var actualResult = CalculatorExecutor.Calculate(expression);
actualResult.Should().Be(expectedResult);
}