Find the bug
time to read 1 min | 120 words

Can you find the bug in here?

public void Receiver(object ignored)
{
	while (keepRunning)
	{
		using (var tx = new TransactionScope())
		{
			Message msg;
			try
			{
				msg = receiver.Receive("uno", null, new TimeSpan(0, 0, 10));
			}
			catch (TimeoutException)
			{
				continue;
			}
			catch(ObjectDisposedException)
			{
				continue;
			}
			lock (msgs)
			{
				msgs.Add(Encoding.ASCII.GetString(msg.Data));
				Console.WriteLine(msgs.Count);
			}
			tx.Complete();
		}
	}
}

And:

[Fact]
public void ShouldOnlyGetTwoItems()
{
	ThreadPool.QueueUserWorkItem(Receiver);

	Sender(4);

	Sender(5);

	while(true)
	{
		lock (msgs)
		{
			if (msgs.Count>1)
				break;
		}
		Thread.Sleep(100);
	}
	Thread.Sleep(2000);//let it try to do something in addition to that
	receiver.Dispose();
	keepRunning = false;

	Assert.Equal(2, msgs.Count);
	Assert.Equal("Message 4", msgs[0]);
	Assert.Equal("Message 5", msgs[1]);
}

I will hint that you cannot make any part of the receiver after it was disposed.

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