public void RegisterTask_AsynchronousCompletion_SwallowsExceptionsThrownByEndDelegate() {
// Arrange
SimpleSynchronizationContext syncContext = new SimpleSynchronizationContext();
AsyncManager asyncManager = new AsyncManager(syncContext);
bool endDelegateWasCalled = false;
ManualResetEvent waitHandle = new ManualResetEvent(false /* initialState */);
Func<AsyncCallback, IAsyncResult> beginDelegate = callback => {
MockAsyncResult asyncResult = new MockAsyncResult(false /* completedSynchronously */);
ThreadPool.QueueUserWorkItem(_ => {
callback(asyncResult);
waitHandle.Set();
});
return asyncResult;
};
Action<IAsyncResult> endDelegate = delegate {
endDelegateWasCalled = true;
throw new Exception("This is a sample exception.");
};
// Act
asyncManager.RegisterTask(beginDelegate, endDelegate);
waitHandle.WaitOne();
// Assert
Assert.IsTrue(endDelegateWasCalled);
Assert.AreEqual(0, asyncManager.OutstandingOperations.Count, "Counter was not decremented properly.");
}
public void RegisterTask_AsynchronousCompletion() {
// Arrange
SimpleSynchronizationContext syncContext = new SimpleSynchronizationContext();
AsyncManager asyncManager = new AsyncManager(syncContext);
bool endDelegateWasCalled = false;
ManualResetEvent waitHandle = new ManualResetEvent(false /* initialState */);
Func<AsyncCallback, IAsyncResult> beginDelegate = callback => {
Assert.AreEqual(1, asyncManager.OutstandingOperations.Count, "Counter was not incremented properly.");
MockAsyncResult asyncResult = new MockAsyncResult(false /* completedSynchronously */);
ThreadPool.QueueUserWorkItem(_ => {
Assert.AreEqual(1, asyncManager.OutstandingOperations.Count, "Counter shouldn't have been decremented yet.");
callback(asyncResult);
waitHandle.Set();
});
return asyncResult;
};
Action<IAsyncResult> endDelegate = delegate { endDelegateWasCalled = true; };
// Act
asyncManager.RegisterTask(beginDelegate, endDelegate);
waitHandle.WaitOne();
// Assert
Assert.IsTrue(endDelegateWasCalled);
Assert.IsTrue(syncContext.SendWasCalled, "Asynchronous call to End() should have been routed through SynchronizationContext.Send()");
Assert.AreEqual(0, asyncManager.OutstandingOperations.Count, "Counter was not decremented properly.");
}
public void RegisterTask_SynchronousCompletion() {
// Arrange
SimpleSynchronizationContext syncContext = new SimpleSynchronizationContext();
AsyncManager asyncManager = new AsyncManager(syncContext);
bool endDelegateWasCalled = false;
Func<AsyncCallback, IAsyncResult> beginDelegate = callback => {
Assert.AreEqual(1, asyncManager.OutstandingOperations.Count, "Counter was not incremented properly.");
MockAsyncResult asyncResult = new MockAsyncResult(true /* completedSynchronously */);
callback(asyncResult);
return asyncResult;
};
Action<IAsyncResult> endDelegate = delegate { endDelegateWasCalled = true; };
// Act
asyncManager.RegisterTask(beginDelegate, endDelegate);
// Assert
Assert.IsTrue(endDelegateWasCalled);
Assert.IsFalse(syncContext.SendWasCalled, "Synchronous call to End() should not have been routed through SynchronizationContext.Send()");
Assert.AreEqual(0, asyncManager.OutstandingOperations.Count, "Counter was not decremented properly.");
}
public void RegisterTask_ResetsOutstandingOperationCountIfBeginMethodThrows() {
// Arrange
SimpleSynchronizationContext syncContext = new SimpleSynchronizationContext();
AsyncManager asyncManager = new AsyncManager(syncContext);
Func<AsyncCallback, IAsyncResult> beginDelegate = cb => {
throw new InvalidOperationException("BeginDelegate throws.");
};
Action<IAsyncResult> endDelegate = ar => {
Assert.Fail("This should never be called.");
};
// Act & assert
ExceptionHelper.ExpectInvalidOperationException(
delegate {
asyncManager.RegisterTask(beginDelegate, endDelegate);
}, "BeginDelegate throws.");
Assert.AreEqual(0, asyncManager.OutstandingOperations.Count);
}
