async def test_close_subgen_error(self) -> None:
class Exc(Exception):
pass
async def g(fut):
try:
await fut
except GeneratorExit:
raise Exc("error")
alv = AsyncLazyValue(g, asyncio.Future())
i = alv.__await__() # get main coro
i1 = alv.__await__() # get future
i.send(None)
try:
i.close()
self.fail("Error expected")
except Exc:
pass
try:
# check future has gotten Exc exit
next(i1)
self.fail("should not be here")
except Exc as e:
self.assertIs(type(e.__context__), GeneratorExit)
pass
async def test_throw_not_started(self) -> None:
class Exc(Exception):
pass
async def g():
pass
alv = AsyncLazyValue(g)
c = alv.__await__()
try:
c.throw(Exc)
self.fail("Error expected")
except Exc:
pass
async def test_close_normal(self) -> None:
async def g(fut):
await fut
# close non-started asynclazy value is no-op
alv = AsyncLazyValue(g, asyncio.Future())
i = alv.__await__() # get main coro
i1 = alv.__await__() # get future
i.send(None)
i.close()
try:
# check future has gotten generator exit
next(i1)
self.fail("should not be here")
except GeneratorExit:
pass
async def test_close_not_started(self) -> None:
async def g():
pass
# close non-started asynclazy value is no-op
(AsyncLazyValue(g).__await__()).close()
pass
async def test_single_task_cancelled(self) -> None:
"""
Should raise CancelledError()
"""
async def async_func(arg1: int, arg2: int) -> int:
self.log("ran-coro")
self.coro_running.set()
await asyncio.sleep(3)
raise RuntimeError("async_func never got cancelled")
async def async_cancel(task: asyncio.Task,
alv: AsyncLazyValue) -> None:
await asyncio.wait_for(self.coro_running.wait(), timeout=3)
self.log("cancelling")
task.cancel()
self.log("cancelled")
alv = AsyncLazyValue(async_func, 1, 2)
ta = asyncio.ensure_future(alv)
tc = asyncio.ensure_future(async_cancel(ta, alv))
ta_result, tc_result = await asyncio.gather(ta,
tc,
return_exceptions=True)
self.assertSequenceEqual(self.events,
["ran-coro", "cancelling", "cancelled"])
self.assertTrue(isinstance(ta_result, asyncio.CancelledError))
self.assertEqual(tc_result, None)
async def test_throw_unhandled_in_subgen(self) -> None:
class Exc(Exception):
pass
async def g(fut):
try:
await fut
except Exc:
raise IndexError
alv = AsyncLazyValue(g, asyncio.Future())
c = alv.__await__()
c1 = alv.__await__()
c.send(None)
try:
c.throw(Exc)
self.fail("IndexError expected")
except IndexError as e:
self.assertTrue(type(e.__context__) is Exc)
try:
next(c1)
except IndexError as e:
self.assertTrue(type(e.__context__) is Exc)
async def test_throw_handled_in_subgen(self) -> None:
class Exc(Exception):
pass
async def g(fut):
try:
await fut
except Exc:
return 10
alv = AsyncLazyValue(g, asyncio.Future())
c = alv.__await__()
c1 = alv.__await__()
c.send(None)
try:
c.throw(Exc)
except StopIteration as e:
self.assertEqual(e.args[0], 10)
try:
next(c1)
self.fail("StopIteration expected")
except StopIteration as e:
self.assertEqual(e.args[0], 10)
async def test_two_tasks(self) -> None:
call_count = 0
async def async_func(arg1: int, arg2: int) -> int:
nonlocal call_count
call_count += 1
return arg1 + arg2
alv = AsyncLazyValue(async_func, 1, 2)
ta = asyncio.ensure_future(alv)
tb = asyncio.ensure_future(alv)
res = await asyncio.gather(ta, tb)
self.assertEqual(res, [3, 3])
# should only be called once
self.assertEqual(call_count, 1)
async def test_two_tasks_parent_cancelled(self) -> None:
"""
Creates two tasks from the same AsyncLazyValue. Cancels the task which
calls the coroutine first.
"""
async def async_func(arg1: int, arg2: int) -> int:
self.log("ran-coro")
await asyncio.sleep(3)
self.log("completed-coro")
raise RuntimeError("async_func never got cancelled")
async def async_cancel(task: asyncio.Task,
alv: AsyncLazyValue) -> None:
start = time()
while alv._awaiting_tasks < 1:
# Sleep until both tasks are awaiting on the future (one of them
# is awaiting on async_func, so we only wait until the count
# is 1). Also, we timeout if we wait more than 3 seconds
now = time()
if now - start > 3:
raise RuntimeError(
"cannot cancel since the tasks are not waiting on the future"
)
await asyncio.sleep(0)
self.log("cancelling")
task.cancel()
self.log("cancelled")
alv = AsyncLazyValue(async_func, 1, 2)
ta = asyncio.ensure_future(alv)
tb = asyncio.ensure_future(alv)
# pyre-fixme[6]: Expected `Task[Any]` for 1st param but got `Future[Any]`.
tc = asyncio.ensure_future(async_cancel(ta, alv))
ta_result, tb_result, tc_result = await asyncio.gather(
ta, tb, tc, return_exceptions=True)
self.assertSequenceEqual(self.events,
["ran-coro", "cancelling", "cancelled"])
self.assertTrue(isinstance(ta_result, asyncio.CancelledError))
self.assertTrue(isinstance(tb_result, asyncio.CancelledError))
self.assertEqual(tc_result, None)
async def test_two_tasks_child_cancelled(self) -> None:
"""
Creates two tasks from the same AsyncLazyValue. Cancels the task which
calls the coroutine second.
"""
async def async_func(arg1: int, arg2: int) -> int:
self.log("ran-coro")
await asyncio.wait_for(self.cancelled.wait(), timeout=3)
return arg1 + arg2
async def async_cancel(task: asyncio.Task,
alv: AsyncLazyValue) -> None:
start = time()
while alv._awaiting_tasks < 1:
# Sleep until both tasks are awaiting on the future (one of them
# is awaiting on async_func, so we only wait until the count
# is 1). Also, we timeout if we wait more than 3 seconds
now = time()
if now - start > 3:
raise RuntimeError(
"cannot cancel since the tasks are not waiting on the future"
)
await asyncio.sleep(0)
self.log("cancelling")
task.cancel()
self.cancelled.set()
self.log("cancelled")
alv = AsyncLazyValue(async_func, 1, 2)
ta = asyncio.ensure_future(alv)
tb = asyncio.ensure_future(alv)
tc = asyncio.ensure_future(async_cancel(tb, alv))
ta_result, tb_result, tc_result = await asyncio.gather(
ta, tb, tc, return_exceptions=True)
self.assertSequenceEqual(self.events,
["ran-coro", "cancelling", "cancelled"])
self.assertEqual(ta_result, 3)
self.assertTrue(isinstance(tb_result, asyncio.CancelledError))
self.assertEqual(tc_result, None)
async def test_throw_1(self):
async def l0(alv):
return await l1(alv)
async def l1(alv):
return await l2(alv)
async def l2(alv):
return await alv
async def val(f):
try:
await f
except:
pass
return 42
f = asyncio.Future()
alv = AsyncLazyValue(val, f)
l = asyncio.get_running_loop()
l.call_later(1, lambda: f.set_exception(NotImplementedError))
x = await l0(alv)
self.assertEqual(x, 42)
async def test_ok_path(self) -> None:
async def async_func(arg1: int, arg2: int) -> int:
return arg1 + arg2
alv = AsyncLazyValue(async_func, 1000, 2000)
self.assertEqual(await alv, 3000)