You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

82 lines
2.0 KiB

# Test cancelling a task
try:
import asyncio
except ImportError:
print("SKIP")
raise SystemExit
async def task(s, allow_cancel):
try:
print("task start")
await asyncio.sleep(s)
print("task done")
except asyncio.CancelledError as er:
print("task cancel")
if allow_cancel:
raise er
async def task2(allow_cancel):
print("task 2")
try:
await asyncio.create_task(task(0.05, allow_cancel))
except asyncio.CancelledError as er:
print("task 2 cancel")
raise er
print("task 2 done")
async def main():
# Cancel task immediately
t = asyncio.create_task(task(2, True))
print(t.cancel())
# Cancel task after it has started
t = asyncio.create_task(task(2, True))
await asyncio.sleep(0.01)
print(t.cancel())
print("main sleep")
await asyncio.sleep(0.01)
# Cancel task multiple times after it has started
t = asyncio.create_task(task(2, True))
await asyncio.sleep(0.01)
for _ in range(4):
print(t.cancel())
print("main sleep")
await asyncio.sleep(0.01)
# Await on a cancelled task
print("main wait")
try:
await t
except asyncio.CancelledError:
print("main got CancelledError")
# Cancel task after it has finished
t = asyncio.create_task(task(0.01, False))
await asyncio.sleep(0.05)
print(t.cancel())
# Nested: task2 waits on task, task2 is cancelled (should cancel task then task2)
print("----")
t = asyncio.create_task(task2(True))
await asyncio.sleep(0.01)
print("main cancel")
t.cancel()
print("main sleep")
await asyncio.sleep(0.1)
# Nested: task2 waits on task, task2 is cancelled but task doesn't allow it (task2 should continue)
print("----")
t = asyncio.create_task(task2(False))
await asyncio.sleep(0.01)
print("main cancel")
t.cancel()
print("main sleep")
await asyncio.sleep(0.1)
asyncio.run(main())