public void And_setting_exists_Then_existing_setting_should_be_replaced()
{
var settings = new AppSettings("NonExistingFile", FileOption.None);
var settingName = "setting";
// Original value
settings.SetValue<int>(settingName, 1);
Assert.AreEqual(1, settings.GetValue<int>(settingName));
// Save with different value
settings.SetValue<int>(settingName, 2);
Assert.AreEqual(2, settings.GetValue<int>(settingName));
}