public void Exchange_Twice_SecondFalse()
{
var subject = new AtomicBool();
Assert.True(subject.Exchange(true));
Assert.False(subject.Exchange(true));
}
public void Exchange_Concurrent()
{
int accessedTimes = 0;
var gate = new object();
var evt = new ManualResetEvent(false);
AtomicBool subject = false;
Task[] tasks = Enumerable.Repeat(
Task.Run(
() =>
{
lock (gate)
{
evt.WaitOne();
}
if (subject.Exchange(true))
{
Interlocked.Increment(ref accessedTimes);
}
}),
10)
.ToArray();
evt.Set();
Assert.True(Task.WaitAll(tasks, TimeSpan.FromSeconds(10)));
Assert.Equal(1, accessedTimes);
}