def test_iterate():
"""
You can read a Channel to the end by iterating it.
"""
chnl = Channel()
chnl.put_many(range(5))
chnl.end()
assert list(chnl) == [0, 1, 2, 3, 4]
def test_thread_source_channel():
"""
Everything thread_source does, it can do when the output channel is
specified by the user insted of created by the call to thread_source()
"""
my_chnl = Channel()
my_chnl.put_many(range(5))
# This is the basic behaviour.
chnl = channel.thread_source(range(10), channel=my_chnl)
assert chnl is my_chnl
assert list(chnl) == list(range(5)) + list(range(10))
def test_suppressed():
"""
The Channel exceptions both have a special suppress helper.
"""
chnl = Channel()
chnl.end()
with channel.Finished.suppress():
chnl.get()
chnl = Channel()
chnl.cancel()
with channel.Cancelled.suppress():
chnl.get()
def test_put_get():
"""
Channel is a FIFO queue. Write with put() or put_many(), then read with
get().
"""
chnl = Channel()
chnl.put(1)
chnl.put(2)
assert chnl.get() == 1
chnl.put(3)
assert chnl.get() == 2
assert chnl.get() == 3
chnl.put_many([4, 5])
assert chnl.get() == 4
assert chnl.get() == 5
def test_cancelled():
"""
Once you cancel a Channel, get() raises Cancelled.
"""
chnl = Channel()
chnl.cancel()
with pytest.raises(channel.Cancelled):
chnl.get()
with pytest.raises(channel.Cancelled):
chnl.get()
def test_suppressed_decorator():
"""
Channel exception suppression also works as a decorator.
"""
@channel.Finished.suppress()
def get():
chnl.get()
chnl = Channel()
chnl.end()
get()
chnl = Channel()
chnl.cancel()
with pytest.raises(channel.Cancelled):
get()
channel.Cancelled.suppress()(get)()
def test_channel_param(tmp_path):
"""
recurse_files() and recurse_filestats() accept a channel parameter.
"""
with tempfiles(tmp_path):
assert set(file.recurse_files(tmp_path)) == set(file.recurse_files(tmp_path, channel=QueueChannel()))
assert set(file.recurse_filestats(tmp_path)) == set(file.recurse_filestats(tmp_path, channel=QueueChannel()))
def test_priority_callable():
"""
Prioritised channel can have custom sort order.
"""
chnl = Channel(priority=lambda value: -value)
values = (3, 2, 1, 1, 2, 3, 7)
chnl.put_many(values).end()
assert tuple(chnl) == tuple(sorted(values, reverse=True))
# And this still works with the gets mixed into the puts
chnl = Channel(priority=lambda value: -value)
chnl.put(2)
chnl.put(1)
assert chnl.get() == 2
chnl.put(0)
assert chnl.get() == 1
chnl.put(3)
assert chnl.get() == 3
assert chnl.get() == 0
def test_priority():
"""
FIFO behaviour can be changed to a priority queue.
"""
chnl = Channel(priority=True)
values = (3, 2, 1, 1, 2, 3, 7)
chnl.put_many(values).end()
assert tuple(chnl) == tuple(sorted(values))
# And this still works with the gets mixed into the puts
chnl = Channel(priority=True)
chnl.put(2)
chnl.put(1)
assert chnl.get() == 1
chnl.put(0)
assert chnl.get() == 0
chnl.put(3)
assert chnl.get() == 2
assert chnl.get() == 3
def test_finished():
"""
Once you end a channel, get() raises Finished.
"""
chnl = Channel()
chnl.end()
with pytest.raises(channel.Finished):
chnl.get()
with pytest.raises(channel.Finished):
chnl.get()
chnl = Channel()
chnl.put_many([1, 2, 3]).end()
assert chnl.get() == 1
assert chnl.get() == 2
assert chnl.get() == 3
with pytest.raises(channel.Finished):
chnl.get()
with pytest.raises(channel.Finished):
chnl.get()
def test_end_states():
"""
Once cancelled, a Channel stays that way. If ended, though,
it can be cancelled to prevent any remaining data being read.
"""
chnl = Channel()
chnl.cancel()
with pytest.raises(channel.Cancelled):
chnl.put(1)
with pytest.raises(channel.Cancelled):
chnl.get()
chnl.cancel()
with pytest.raises(channel.Cancelled):
chnl.get()
chnl.end()
with pytest.raises(channel.Cancelled):
chnl.get()
chnl = Channel()
chnl.end()
with pytest.raises(channel.Finished):
chnl.get()
with pytest.raises(channel.Finished):
chnl.put(1)
chnl.end()
with pytest.raises(channel.Finished):
chnl.get()
chnl.cancel()
with pytest.raises(channel.Cancelled):
chnl.get()
chnl = Channel()
chnl.put_many([1, 2, 3])
chnl.end()
assert chnl.get() == 1
chnl.cancel()
with pytest.raises(channel.Cancelled):
chnl.get()