Here is an example:
---
import asyncio
def bug():
raise Exception("error in bar")
@asyncio.coroutine
def work2():
yield from []
loop.call_soon(bug)
@asyncio.coroutine
def work():
yield from work2()
def schedule():
loop.create_task(work())
loop = asyncio.get_event_loop()
loop.call_soon(schedule)
loop.run_forever()
loop.close()
---
Current output in debug mode:
---
Exception in callback bug() at y.py:3
handle: <Handle bug() at y.py:3 created at y.py:9>
source_traceback: Object created at (most recent call last):
File "y.py", line 20, in <module>
loop.run_forever()
File "/home/haypo/prog/HG/tulip/asyncio/base_events.py", line 244,
in run_forever
self._run_once()
File "/home/haypo/prog/HG/tulip/asyncio/base_events.py", line 1083,
in _run_once
handle._run()
File "/home/haypo/prog/HG/tulip/asyncio/events.py", line 120, in _run
self._callback(*self._args)
File "/home/haypo/prog/HG/tulip/asyncio/tasks.py", line 237, in _step
result = next(coro)
File "/home/haypo/prog/HG/tulip/asyncio/coroutines.py", line 79, in __next__
return next(self.gen)
File "y.py", line 13, in work
yield from work2()
File "/home/haypo/prog/HG/tulip/asyncio/coroutines.py", line 79, in __next__
return next(self.gen)
File "y.py", line 9, in work2
loop.call_soon(bug)
Traceback (most recent call last):
File "/home/haypo/prog/HG/tulip/asyncio/events.py", line 120, in _run
self._callback(*self._args)
File "y.py", line 4, in bug
raise Exception("error in bar")
Exception: error in bar
---
I don't see how the work() task was scheduled, nor the call to scheduled.
Debug output with the latest patch:
---
Exception in callback bug() at y.py:3
handle: <Handle bug() at y.py:3 created at y.py:9>
source_traceback: Object created at (most recent call last):
File "y.py", line 19, in <module>
loop.call_soon(schedule)
File "y.py", line 19, in <module>
<injected handle>
File "/home/haypo/prog/HG/tulip/asyncio/events.py", line 125, in _run
self._callback(*self._args)
File "y.py", line 16, in schedule
loop.create_task(work())
File "y.py", line 16, in schedule
<injected task>
File "/home/haypo/prog/HG/tulip/asyncio/tasks.py", line 237, in _step
result = next(coro)
File "/home/haypo/prog/HG/tulip/asyncio/coroutines.py", line 79, in __next__
return next(self.gen)
File "y.py", line 13, in work
yield from work2()
File "/home/haypo/prog/HG/tulip/asyncio/coroutines.py", line 79, in __next__
return next(self.gen)
File "y.py", line 9, in work2
loop.call_soon(bug)
Traceback (most recent call last):
File "/home/haypo/prog/HG/tulip/asyncio/events.py", line 125, in _run
self._callback(*self._args)
File "y.py", line 4, in bug
raise Exception("error in bar")
Exception: error in bar
---
Here you can see the full chain: schedule -> work -> work2 -> bug.
Victor
