public void CalculateIncomeTax_ShouldNotReturnNull_WhenCountryCodeIsValid()
{
// Arrange
_mockTaxCalculatorService.Setup(x => x.Calculate("TR", 32000m))
.Returns(5300m);
// Act
var result = _sut.CalculateIncomeTax("TR", 32000m) as OkObjectResult;
// Assert
Assert.NotNull(result);
}
