QColor::fromHsl changes the given saturation value

If I create QColor from HSL values, created QColor has different saturation value than what was given as a parameter to QColor::fromHsl() function. It seems that saturation value is affected by lightness value also given as a parameter.

If I use QColor::lighter() or darker() functions, it does not change the saturation because QColor is first converted to HSV and lightness is applied to (V)alue.

If this is working as intended, would it be possible to explain this in the documentations?

I have attached an example project to demonstrate this issue