public void PostingTest()
{
// prepare
using var syncContext = new SingleThreadSynchronizationContext();
// check call-back execution thread
var executionThread = (Thread?)null;
syncContext.Post(() =>
{
executionThread = Thread.CurrentThread;
});
Thread.Sleep(100);
Assert.AreSame(syncContext.ExecutionThread, executionThread, "Call-back should be executed on execution thread.");
// post call-backs continuously from multiple threads.
var syncLock = new object();
var nextPostingId = 1;
var expectedPostingId = 1;
var exception = (Exception?)null;
lock (syncLock)
{
for (var i = 0; i < 100; ++i)
{
ThreadPool.QueueUserWorkItem(_ =>
{
lock (syncLock)
{
var postingId = nextPostingId++;
syncContext.Post(() =>
{
try
{
Assert.AreEqual(expectedPostingId, postingId, "Incorrect call-back execution order.");
Thread.Sleep(10);
++expectedPostingId;
}
catch (Exception ex)
{
exception = ex;
}
finally
{
if (postingId == 100 || exception != null)
{
lock (syncLock)
Monitor.Pulse(syncLock);
}
}
});
}
});
}
Assert.IsTrue(Monitor.Wait(syncLock, 10000), "Cannot complete waiting for all call-backs.");
if (exception != null)
{
throw exception;
}
}
}