public async Task Creates_item_only_once_when_get_value_is_called_in_parallel()
{
CancellationToken ct = CancellationToken.None;
var blockFactoryMethod = true;
var asyncGenericBuffer = new AsyncGenericBuffer <object>(
factory: _ =>
{
while (blockFactoryMethod)
{
}
return(Task.FromResult(new object()));
},
bufferingPeriod: TimeSpan.FromTicks(1),
clock: ClockFactory.FrozenClock());
var tasks = Enumerable.Range(0, 1000)
.Select(_ => Task.Run(async() => await asyncGenericBuffer.GetValueAsync(ct)));
blockFactoryMethod = false;
await Task.Delay(2000);
object[] results = await Task.WhenAll(tasks);
foreach (var result in results)
{
Assert.Same(results.First(), result);
}
}
public async Task Returns_the_same_object_while_in_the_same_buffering_period()
{
CancellationToken ct = CancellationToken.None;
DateTime dateTime = DateTime.MinValue;
var bufferingPeriod = TimeSpan.FromTicks(1);
var asyncGenericBuffer = new AsyncGenericBuffer <object>(factory: _ => Task.FromResult(new object()), bufferingPeriod: bufferingPeriod, clock: () => dateTime);
object firstValue = await asyncGenericBuffer.GetValueAsync(ct);
Assert.Same(firstValue, await asyncGenericBuffer.GetValueAsync(ct));
Assert.Same(firstValue, await asyncGenericBuffer.GetValueAsync(ct));
dateTime += bufferingPeriod;
Assert.NotSame(firstValue, await asyncGenericBuffer.GetValueAsync(ct));
Assert.Same(await asyncGenericBuffer.GetValueAsync(ct), await asyncGenericBuffer.GetValueAsync(ct));
}
public async Task Returns_new_value_after_buffering_period_passes()
{
CancellationToken ct = CancellationToken.None;
DateTime dateTime = DateTime.MinValue;
var bufferingPeriod = TimeSpan.FromTicks(1);
var incrementalClock = new IncrementalClock();
int executions = 0;
var asyncGenericBuffer = new AsyncGenericBuffer <int>(factory: _ => Task.FromResult(executions++), bufferingPeriod: bufferingPeriod, clock: () => dateTime);
Assert.Equal(0, await asyncGenericBuffer.GetValueAsync(ct)); // Before buffering period is past
dateTime += bufferingPeriod;
Assert.Equal(1, await asyncGenericBuffer.GetValueAsync(ct)); // After first buffering period is past
dateTime += bufferingPeriod;
Assert.Equal(2, await asyncGenericBuffer.GetValueAsync(ct)); // After second buffering period is past
}
public async Task Reset_forces_creating_a_new_value()
{
CancellationToken ct = CancellationToken.None;
var asyncGenericBuffer = new AsyncGenericBuffer <object>(
factory: _ => Task.FromResult(new object()),
bufferingPeriod: TimeSpan.FromTicks(1),
clock: ClockFactory.FrozenClock());
var firstObject = await asyncGenericBuffer.GetValueAsync(ct);
Assert.Same(firstObject, await asyncGenericBuffer.GetValueAsync(ct));
Assert.Same(firstObject, await asyncGenericBuffer.GetValueAsync(ct));
await asyncGenericBuffer.ResetAsync(ct);
Assert.NotSame(firstObject, await asyncGenericBuffer.GetValueAsync(ct));
}
public async Task Force_fefresh_creates_new_value_even_if_the_old_one_is_still_valid()
{
CancellationToken ct = CancellationToken.None;
var asyncGenericBuffer = new AsyncGenericBuffer <object>(
factory: _ => Task.FromResult(new object()),
bufferingPeriod: TimeSpan.FromTicks(1),
clock: ClockFactory.FrozenClock());
var val1 = await asyncGenericBuffer.GetValueAsync(ct);
var val2 = await asyncGenericBuffer.GetValueAsync(ct);
var forced = await asyncGenericBuffer.ForceRefreshAsync(ct);
var val3 = await asyncGenericBuffer.GetValueAsync(ct);
var val4 = await asyncGenericBuffer.GetValueAsync(ct);
Assert.Same(val1, val2);
Assert.NotSame(val1, forced);
Assert.Same(forced, val3);
Assert.Same(val3, val4);
}
WeakReference CreateBufferWeakReference()
{
var buffer = new AsyncGenericBuffer <Object>(_ => Task.FromResult(new Object()), TimeSpan.FromSeconds(5));
return(new WeakReference(buffer));
}
