Exception raised while exiting a TimeoutAfter context manager

[rapha-opensource]

TypeError: '>' not supported between instances of 'NoneType' and 'float'

It shows up here: https://github.com/dabeaz/curio/blob/97475342e4f6b4d56e9a0393db8472e7dcd68bfa/curio/task.py#L839

It's part of a unit test that does something like this:

i = 0
async with timeout_after(1):
      try:
           while True:
                 self.assertEqual( 'yo mama', await echo('yo mama') )
                 i += 1
      except TimeoutCancellationError:
           pass

This runs most of the time, but once every 4-5 times, it throws. I have not dug more deeply yet, hoping that the problem might jump to someone's eyes first. My 'echo' coroutine function involves more complicated stuff (Channels, network, etc.) though it is not obvious to me how that would be causing the problem.

[dabeaz]

Pushed a possible fix for this. Try and let me know if the problem goes away.

[rapha-opensource]

The problem went away. Thank you for the quick turnaround!