1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
# Test asyncio.wait_for
try:
import asyncio
except ImportError:
print("SKIP")
raise SystemExit
async def task(id, t):
print("task start", id)
await asyncio.sleep(t)
print("task end", id)
return id * 2
async def task_catch():
print("task_catch start")
try:
await asyncio.sleep(0.2)
except asyncio.CancelledError:
print("ignore cancel")
print("task_catch done")
async def task_raise():
print("task start")
raise ValueError
async def task_cancel_other(t, other):
print("task_cancel_other start")
await asyncio.sleep(t)
print("task_cancel_other cancel")
other.cancel()
async def task_wait_for_cancel(id, t, t_wait):
print("task_wait_for_cancel start")
try:
await asyncio.wait_for(task(id, t), t_wait)
except asyncio.CancelledError as er:
print("task_wait_for_cancel cancelled")
raise er
async def task_wait_for_cancel_ignore(t_wait):
print("task_wait_for_cancel_ignore start")
try:
await asyncio.wait_for(task_catch(), t_wait)
except asyncio.CancelledError as er:
print("task_wait_for_cancel_ignore cancelled")
raise er
async def main():
sep = "-" * 10
# When task finished before the timeout
print(await asyncio.wait_for(task(1, 0.01), 10))
print(sep)
# When timeout passes and task is cancelled
try:
print(await asyncio.wait_for(task(2, 10), 0.01))
except asyncio.TimeoutError:
print("timeout")
print(sep)
# When timeout passes and task is cancelled, but task ignores the cancellation request
try:
print(await asyncio.wait_for(task_catch(), 0.1))
except asyncio.TimeoutError:
print("TimeoutError")
print(sep)
# When task raises an exception
try:
print(await asyncio.wait_for(task_raise(), 1))
except ValueError:
print("ValueError")
print(sep)
# Timeout of None means wait forever
print(await asyncio.wait_for(task(3, 0.1), None))
print(sep)
# When task is cancelled by another task
t = asyncio.create_task(task(4, 10))
asyncio.create_task(task_cancel_other(0.01, t))
try:
print(await asyncio.wait_for(t, 1))
except asyncio.CancelledError as er:
print(repr(er))
print(sep)
# When wait_for gets cancelled
t = asyncio.create_task(task_wait_for_cancel(4, 1, 2))
await asyncio.sleep(0.01)
t.cancel()
await asyncio.sleep(0.01)
print(sep)
# When wait_for gets cancelled and awaited task ignores the cancellation request
t = asyncio.create_task(task_wait_for_cancel_ignore(2))
await asyncio.sleep(0.01)
t.cancel()
await asyncio.sleep(0.01)
print(sep)
# When wait_for gets cancelled and the task it's waiting on finishes around the
# same time as the cancellation of the wait_for
for num_sleep in range(1, 5):
t = asyncio.create_task(task_wait_for_cancel(4 + num_sleep, 0, 2))
for _ in range(num_sleep):
await asyncio.sleep(0)
assert not t.done()
print("cancel wait_for")
t.cancel()
try:
await t
except asyncio.CancelledError as er:
print(repr(er))
print(sep)
print("finish")
asyncio.run(main())
|
