async def test_take(assert_run, event_loop):
with event_loop.assert_cleanup():
xs = stream.count() | add_resource.pipe(1) | pipe.take(3)
await assert_run(xs, [0, 1, 2])
with event_loop.assert_cleanup():
xs = stream.count() | add_resource.pipe(1) | pipe.take(0)
await assert_run(xs, [])
async def test_take(assert_run, event_loop):
with event_loop.assert_cleanup():
xs = stream.count() | add_resource.pipe(1) | pipe.take(3)
await assert_run(xs, [0, 1, 2])
with event_loop.assert_cleanup():
xs = stream.count() | add_resource.pipe(1) | pipe.take(0)
await assert_run(xs, [])
async def main():
# Create a counting stream with a 0.2 seconds interval
xs = stream.count(interval=0.2)
# Operators can be piped using '|'
ys = xs | pipe.map(lambda x: x**2)
# Streams can be sliced
zs = ys[1:10:2]
# Use a stream context for proper resource management
async with zs.stream() as streamer:
# Asynchronous iteration
async for z in streamer:
# Print 1, 9, 25, 49 and 81
print("->", z)
# Streams can be awaited and return the last value
print("9² = ", await zs)
# Streams can run several times
print("9² = ", await zs)
# Streams can be concatenated
one_two_three = stream.just(1) + stream.range(2, 4)
# Print [1, 2, 3]
print(await stream.list(one_two_three))
async def main():
# Create a counting stream with a 0.2 seconds interval
xs = stream.count(interval=0.2)
# Operators can be piped using '|'
ys = xs | pipe.map(lambda x: x**2)
# Streams can be sliced
zs = ys[1:10:2]
# Use a stream context for proper resource management
async with zs.stream() as streamer:
# Asynchronous iteration
async for z in streamer:
# Print 1, 9, 25, 49 and 81
print('->', z)
# Streams can be awaited and return the last value
print('9² = ', await zs)
# Streams can run several times
print('9² = ', await zs)
# Streams can be concatenated
one_two_three = stream.just(1) + stream.range(2, 4)
# Print [1, 2, 3]
print(await stream.list(one_two_three))
async def main():
# This stream computes 11² + 13² in 1.5 second
xs = (
stream.count(interval=0.1) # Count from zero every 0.1 s
| pipe.skip(10) # Skip the first 10 numbers
| pipe.take(5) # Take the following 5
| pipe.filter(lambda x: x % 2) # Keep odd numbers
| pipe.map(lambda x: x**2) # Square the results
| pipe.accumulate() # Add the numbers together
)
print('11² + 13² = ', await xs)
async def main():
# This stream computes 11² + 13² in 1.5 second
xs = (
stream.count(interval=0.1) # Count from zero every 0.1 s
| pipe.skip(10) # Skip the first 10 numbers
| pipe.take(5) # Take the following 5
| pipe.filter(lambda x: x % 2) # Keep odd numbers
| pipe.map(lambda x: x ** 2) # Square the results
| pipe.accumulate() # Add the numbers together
)
print('11² + 13² = ', await xs)
async def test_chunks(assert_run, event_loop):
with event_loop.assert_cleanup():
xs = stream.range(3, interval=1) | pipe.chunks(3)
await assert_run(xs, [[0, 1, 2]])
with event_loop.assert_cleanup():
xs = stream.range(4, interval=1) | pipe.chunks(3)
await assert_run(xs, [[0, 1, 2], [3]])
with event_loop.assert_cleanup():
xs = stream.range(5, interval=1) | pipe.chunks(3)
await assert_run(xs, [[0, 1, 2], [3, 4]])
with event_loop.assert_cleanup():
xs = stream.count(interval=1) | add_resource.pipe(1) | pipe.chunks(3)
await assert_run(xs[:1], [[0, 1, 2]])
async def test_chunks(assert_run, event_loop):
with event_loop.assert_cleanup():
xs = stream.range(3, interval=1) | pipe.chunks(3)
await assert_run(xs, [[0, 1, 2]])
with event_loop.assert_cleanup():
xs = stream.range(4, interval=1) | pipe.chunks(3)
await assert_run(xs, [[0, 1, 2], [3]])
with event_loop.assert_cleanup():
xs = stream.range(5, interval=1) | pipe.chunks(3)
await assert_run(xs, [[0, 1, 2], [3, 4]])
with event_loop.assert_cleanup():
xs = (stream.count(interval=1)
| add_resource.pipe(1)
| pipe.chunks(3))
await assert_run(xs[:1], [[0, 1, 2]])
async def test_map(assert_run, event_loop):
# Synchronous/simple
with event_loop.assert_cleanup():
xs = stream.range(5) | pipe.map(lambda x: x**2)
expected = [x**2 for x in range(5)]
await assert_run(xs, expected)
# Synchronous/multiple
with event_loop.assert_cleanup():
xs = stream.range(5)
ys = xs | pipe.map(lambda x, y: x + y, xs)
expected = [x * 2 for x in range(5)]
await assert_run(ys, expected)
# Asynchronous/simple/concurrent
with event_loop.assert_cleanup():
xs = stream.range(1, 4) | pipe.map(asyncio.sleep)
expected = [None] * 3
await assert_run(xs, expected)
assert event_loop.steps == [1, 1, 1]
# Asynchronous/simple/sequential
with event_loop.assert_cleanup():
xs = stream.range(1, 4) | pipe.map(asyncio.sleep, task_limit=1)
expected = [None] * 3
await assert_run(xs, expected)
assert event_loop.steps == [1, 2, 3]
# Asynchronous/multiple/concurrent
with event_loop.assert_cleanup():
xs = stream.range(1, 4)
ys = xs | pipe.map(asyncio.sleep, xs)
await assert_run(ys, [1, 2, 3])
assert event_loop.steps == [1, 1, 1]
# Asynchronous/multiple/sequential
with event_loop.assert_cleanup():
xs = stream.range(1, 4)
ys = xs | pipe.map(asyncio.sleep, xs, task_limit=1)
await assert_run(ys, [1, 2, 3])
assert event_loop.steps == [1, 2, 3]
# As completed
with event_loop.assert_cleanup():
xs = stream.iterate([2, 4, 1, 3, 5])
ys = xs | pipe.map(asyncio.sleep, xs, ordered=False)
await assert_run(ys, [1, 2, 3, 4, 5])
assert event_loop.steps == [1, 1, 1, 1, 1]
# Invalid argument
with pytest.raises(ValueError):
await (stream.range(1, 4) | pipe.map(asyncio.sleep, task_limit=0))
# Break
with event_loop.assert_cleanup():
xs = stream.count(1)
ys = xs | pipe.map(asyncio.sleep, xs, task_limit=10)
await assert_run(ys[:3], [1, 2, 3])
assert event_loop.steps == [1, 1, 1]
# Stuck
with event_loop.assert_cleanup():
xs = stream.count(1)
ys = xs | pipe.map(asyncio.sleep, xs, task_limit=1) | pipe.timeout(5)
await assert_run(ys, [1, 2, 3, 4], asyncio.TimeoutError())
# Force await
with event_loop.assert_cleanup():
xs = stream.iterate([1, 2, 3])
ys = xs | pipe.map(async_(lambda x: asyncio.sleep(x, x)))
await assert_run(ys, [1, 2, 3])
assert event_loop.steps == [1, 1, 1]
# Map await_
with event_loop.assert_cleanup():
xs = stream.iterate(map(lambda x: asyncio.sleep(x, x), [1, 2, 3]))
ys = xs | pipe.map(await_)
await assert_run(ys, [1, 2, 3])
assert event_loop.steps == [1, 1, 1]
async def test_count(assert_run):
xs = stream.count(3, 2)[:4]
await assert_run(xs, [3, 5, 7, 9])
async def test_map(assert_run, event_loop):
# Synchronous/simple
with event_loop.assert_cleanup():
xs = stream.range(5) | pipe.map(lambda x: x**2)
expected = [x**2 for x in range(5)]
await assert_run(xs, expected)
# Synchronous/multiple
with event_loop.assert_cleanup():
xs = stream.range(5)
ys = xs | pipe.map(lambda x, y: x+y, xs)
expected = [x*2 for x in range(5)]
await assert_run(ys, expected)
# Asynchronous/simple/concurrent
with event_loop.assert_cleanup():
xs = stream.range(1, 4) | pipe.map(asyncio.sleep)
expected = [None] * 3
await assert_run(xs, expected)
assert event_loop.steps == [1, 1, 1]
# Asynchronous/simple/sequential
with event_loop.assert_cleanup():
xs = stream.range(1, 4) | pipe.map(asyncio.sleep, task_limit=1)
expected = [None] * 3
await assert_run(xs, expected)
assert event_loop.steps == [1, 2, 3]
# Asynchronous/multiple/concurrent
with event_loop.assert_cleanup():
xs = stream.range(1, 4)
ys = xs | pipe.map(asyncio.sleep, xs)
await assert_run(ys, [1, 2, 3])
assert event_loop.steps == [1, 1, 1]
# Asynchronous/multiple/sequential
with event_loop.assert_cleanup():
xs = stream.range(1, 4)
ys = xs | pipe.map(asyncio.sleep, xs, task_limit=1)
await assert_run(ys, [1, 2, 3])
assert event_loop.steps == [1, 2, 3]
# As completed
with event_loop.assert_cleanup():
xs = stream.iterate([2, 4, 1, 3, 5])
ys = xs | pipe.map(asyncio.sleep, xs, ordered=False)
await assert_run(ys, [1, 2, 3, 4, 5])
assert event_loop.steps == [1, 1, 1, 1, 1]
# Invalid argument
with pytest.raises(ValueError):
await (stream.range(1, 4) | pipe.map(asyncio.sleep, task_limit=0))
# Break
with event_loop.assert_cleanup():
xs = stream.count(1)
ys = xs | pipe.map(asyncio.sleep, xs, task_limit=10)
await assert_run(ys[:3], [1, 2, 3])
assert event_loop.steps == [1, 1, 1]
# Stuck
with event_loop.assert_cleanup():
xs = stream.count(1)
ys = xs | pipe.map(asyncio.sleep, xs, task_limit=1) | pipe.timeout(5)
await assert_run(ys, [1, 2, 3, 4], asyncio.TimeoutError())
# Force await
with event_loop.assert_cleanup():
xs = stream.iterate([1, 2, 3])
ys = xs | pipe.map(async_(lambda x: asyncio.sleep(x, x)))
await assert_run(ys, [1, 2, 3])
assert event_loop.steps == [1, 1, 1]
# Map await_
with event_loop.assert_cleanup():
xs = stream.iterate(map(lambda x: asyncio.sleep(x, x), [1, 2, 3]))
ys = xs | pipe.map(await_)
await assert_run(ys, [1, 2, 3])
assert event_loop.steps == [1, 1, 1]
async def test_count(assert_run):
xs = stream.count(3, 2)[:4]
await assert_run(xs, [3, 5, 7, 9])