async def test_async_gen() -> None:
async with stream.empty().stream() as empty:
async for _ in await force_gen(empty):
pass
with pytest.raises(Exception):
async with stream.throw(Exception(";)")).stream() as err:
async for _ in await force_gen(err):
pass
async with stream.iterate(range(0, 100)).stream() as elems:
assert [x async for x in await force_gen(elems)] == list(range(0, 100))
async def test_merge(assert_run, event_loop):
with event_loop.assert_cleanup():
xs = stream.range(1, 5, 2, interval=2) | pipe.delay(1)
ys = stream.range(0, 5, 2, interval=2) | pipe.merge(xs)
await assert_run(ys, [0, 1, 2, 3, 4])
assert event_loop.steps == [1, 1, 1, 1]
with event_loop.assert_cleanup():
xs = stream.range(1, 5, 2, interval=2) | pipe.delay(1)
ys = stream.range(0, 5, 2, interval=2) | pipe.merge(xs)
await assert_run(ys[:3], [0, 1, 2])
assert event_loop.steps == [1, 1]
with event_loop.assert_cleanup():
xs = stream.just(1) + stream.never()
ys = xs | pipe.merge(xs) | pipe.timeout(1)
await assert_run(ys, [1, 1], asyncio.TimeoutError())
assert event_loop.steps == [1]
# Reproduce issue #65
with event_loop.assert_cleanup():
xs = stream.iterate([1, 2])
ys = stream.iterate([3, 4])
zs = stream.merge(xs, ys) | pipe.take(3)
await assert_run(zs, [1, 2, 3])
with event_loop.assert_cleanup():
xs = stream.iterate([1, 2, 3])
ys = stream.throw(ZeroDivisionError)
zs = stream.merge(xs, ys) | pipe.delay(1) | pipe.take(3)
await assert_run(zs, [1, 2, 3])
# Silencing of a CancelledError
async def agen1():
if False:
yield
try:
await asyncio.sleep(2)
except asyncio.CancelledError:
return
async def agen2():
yield 1
with event_loop.assert_cleanup():
xs = stream.merge(agen1(), agen2()) | pipe.delay(1) | pipe.take(1)
await assert_run(xs, [1])
async def test_concatmap(assert_run, event_loop):
# Concurrent run
with event_loop.assert_cleanup():
xs = stream.range(0, 6, 2, interval=1)
ys = xs | pipe.concatmap(lambda x: stream.range(x, x + 2, interval=5))
await assert_run(ys, [0, 1, 2, 3, 4, 5])
assert event_loop.steps == [1, 1, 3, 5, 5]
# Sequential run
with event_loop.assert_cleanup():
xs = stream.range(0, 6, 2, interval=1)
ys = xs | pipe.concatmap(
lambda x: stream.range(x, x + 2, interval=5), task_limit=1
)
await assert_run(ys, [0, 1, 2, 3, 4, 5])
assert event_loop.steps == [5, 1, 5, 1, 5]
# Limited run
with event_loop.assert_cleanup():
xs = stream.range(0, 6, 2, interval=1)
ys = xs | pipe.concatmap(
lambda x: stream.range(x, x + 2, interval=5), task_limit=2
)
await assert_run(ys, [0, 1, 2, 3, 4, 5])
assert event_loop.steps == [1, 4, 1, 4, 5]
# Make sure item arrive as soon as possible
with event_loop.assert_cleanup():
xs = stream.just(2)
ys = xs | pipe.concatmap(lambda x: stream.range(x, x + 4, interval=1))
zs = ys | pipe.timeout(2) # Sould NOT raise
await assert_run(zs, [2, 3, 4, 5])
assert event_loop.steps == [1, 1, 1]
# An exception might get discarded if the result can be produced before the
# processing of the exception is required
with event_loop.assert_cleanup():
xs = stream.iterate([True, False])
ys = xs | pipe.concatmap(
lambda x: stream.range(0, 3, interval=1)
if x
else stream.throw(ZeroDivisionError)
)
zs = ys | pipe.take(3)
await assert_run(zs, [0, 1, 2])
assert event_loop.steps == [1, 1]
async def test_throw(assert_run):
exception = RuntimeError('Oops')
xs = stream.throw(exception)
await assert_run(xs, [], exception)
async def test_throw(assert_run):
exception = RuntimeError('Oops')
xs = stream.throw(exception)
await assert_run(xs, [], exception)