mirror of
https://github.com/micropython/micropython.git
synced 2025-07-21 13:01:10 +02:00
908f938c44
Some targets don't have f-strings enabled, so try not to use them in tests. Rather, use `str.format`, which is more portable. Signed-off-by: Damien George <damien@micropython.org>
87 lines
2.3 KiB
Python
87 lines
2.3 KiB
Python
# Ensure that an asyncio task can wait on an Event when the
|
|
# _task_queue is empty, in the context of an async iterator
|
|
# https://github.com/micropython/micropython/issues/16318
|
|
|
|
try:
|
|
import asyncio
|
|
except ImportError:
|
|
print("SKIP")
|
|
raise SystemExit
|
|
|
|
# This test requires checking that the asyncio scheduler
|
|
# remains active "indefinitely" when the task queue is empty.
|
|
#
|
|
# To check this, we need another independent scheduler that
|
|
# can wait for a certain amount of time. So we have to
|
|
# create one using micropython.schedule() and time.ticks_ms()
|
|
#
|
|
# Technically, this code breaks the rules, as it is clearly
|
|
# documented that Event.set() should _NOT_ be called from a
|
|
# schedule (soft IRQ) because in some cases, a race condition
|
|
# can occur, resulting in a crash. However:
|
|
# - since the risk of a race condition in that specific
|
|
# case has been analysed and excluded
|
|
# - given that there is no other simple alternative to
|
|
# write this test case,
|
|
# an exception to the rule was deemed acceptable. See
|
|
# https://github.com/micropython/micropython/pull/16772
|
|
|
|
import micropython, time
|
|
|
|
try:
|
|
micropython.schedule
|
|
except AttributeError:
|
|
print("SKIP")
|
|
raise SystemExit
|
|
|
|
ai = None
|
|
|
|
|
|
def schedule_watchdog(end_ticks):
|
|
if time.ticks_diff(end_ticks, time.ticks_ms()) <= 0:
|
|
print("good: asyncio iterator is still pending, exiting")
|
|
# Caution: ai.fetch_data() will invoke Event.set()
|
|
# (see the note in the comment above)
|
|
ai.fetch_data(None)
|
|
return
|
|
micropython.schedule(schedule_watchdog, end_ticks)
|
|
|
|
|
|
async def test(ai):
|
|
for x in range(3):
|
|
await asyncio.sleep(0.1)
|
|
ai.fetch_data("bar {}".format(x))
|
|
|
|
|
|
class AsyncIterable:
|
|
def __init__(self):
|
|
self.message = None
|
|
self.evt = asyncio.Event()
|
|
|
|
def __aiter__(self):
|
|
return self
|
|
|
|
async def __anext__(self):
|
|
await self.evt.wait()
|
|
self.evt.clear()
|
|
if self.message is None:
|
|
raise StopAsyncIteration
|
|
return self.message
|
|
|
|
def fetch_data(self, message):
|
|
self.message = message
|
|
self.evt.set()
|
|
|
|
|
|
async def main():
|
|
global ai
|
|
ai = AsyncIterable()
|
|
asyncio.create_task(test(ai))
|
|
schedule_watchdog(time.ticks_add(time.ticks_ms(), 500))
|
|
async for message in ai:
|
|
print(message)
|
|
print("end main")
|
|
|
|
|
|
asyncio.run(main())
|