The following code has a problem: the generator returned by .wait() has a
finally: section. When self.stopped is set, it still needs to run. As it is
asynchronous (it needs to re-acquire the lock), I need to come up with a
reliable way to wait for it. If I don't, .release() will throw an exception
because the lock is still unlocked.
The best method to do this that I've come up with is the five marked lines.
I keep thinking there must be a better way to do this (taking into account
that I have no idea whether the 'await r' part of this is even necessary).
```
class StopMe(BaseException):
pass
class Foo:
async dev some_method(self):
self.uptodate = asyncio.Condition()
self.stopped = asyncio.Future()
…
await self.uptodate.acquire()
try:
while self.some_condition():
w = self.uptodate.wait()
await asyncio.wait([w,self.stopped], loop=self.conn._loop,
return_when=asyncio.FIRST_COMPLETED)
with contextlib.suppress(StopMe): # FIXME?
r = w.throw(StopMe()) # FIXME?
if r is not None: # FIXME?
await r # FIXME?
await w # FIXME?
finally:
self.uptodate.release()
```
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