public void TimerAccuracy(float interval, float duration)
{
// Skip test when running on Github CI due to high variance in timer latency.
if (Environment.GetEnvironmentVariable("CI") is "true")
{
return;
}
var expectedFires = (int)(interval * 1000 / interval * duration);
var timer = DesktopInterop.Timer;
var list = new List <double>(expectedFires);
var watch = new HPETDeltaStopwatch(true);
timer.Interval = interval;
timer.Elapsed += () =>
{
list.Add(watch.Restart().TotalMilliseconds);
};
timer.Start();
Thread.Sleep(TimeSpan.FromSeconds(duration));
timer.Stop();
// Windows timers are not guaranteed to stop immediately
Thread.Sleep(TimeSpan.FromMilliseconds(50));
var average = list.Average();
var intervalTolerance = interval * TOLERANCE;
var minimum = interval - intervalTolerance;
var maximum = interval + intervalTolerance;
var withinTolerance = (average > minimum) && (average < maximum);
Assert.True(withinTolerance);
}
