cpython/Lib/test/test_interpreters/test_channels.py
Eric Snow 62143736b6
gh-134939: Add the concurrent.interpreters Module (gh-133958)
PEP-734 has been accepted (for 3.14).

(FTR, I'm opposed to putting this under the concurrent package, but
doing so is the SC condition under which the module can land in 3.14.)
2025-06-11 17:35:48 -06:00

601 lines
19 KiB
Python

import importlib
import pickle
import threading
from textwrap import dedent
import unittest
import time
from test.support import import_helper
# Raise SkipTest if subinterpreters not supported.
_channels = import_helper.import_module('_interpchannels')
from concurrent import interpreters
from test.support import channels
from .utils import _run_output, TestBase
class LowLevelTests(TestBase):
# The behaviors in the low-level module is important in as much
# as it is exercised by the high-level module. Therefore the
# most # important testing happens in the high-level tests.
# These low-level tests cover corner cases that are not
# encountered by the high-level module, thus they
# mostly shouldn't matter as much.
# Additional tests are found in Lib/test/test__interpchannels.py.
# XXX Those should be either moved to LowLevelTests or eliminated
# in favor of high-level tests in this file.
def test_highlevel_reloaded(self):
# See gh-115490 (https://github.com/python/cpython/issues/115490).
importlib.reload(channels)
class TestChannels(TestBase):
def test_create(self):
r, s = channels.create()
self.assertIsInstance(r, channels.RecvChannel)
self.assertIsInstance(s, channels.SendChannel)
def test_list_all(self):
self.assertEqual(channels.list_all(), [])
created = set()
for _ in range(3):
ch = channels.create()
created.add(ch)
after = set(channels.list_all())
self.assertEqual(after, created)
def test_shareable(self):
interp = interpreters.create()
rch, sch = channels.create()
self.assertTrue(
interpreters.is_shareable(rch))
self.assertTrue(
interpreters.is_shareable(sch))
sch.send_nowait(rch)
sch.send_nowait(sch)
rch2 = rch.recv()
sch2 = rch.recv()
interp.prepare_main(rch=rch, sch=sch)
sch.send_nowait(rch)
sch.send_nowait(sch)
interp.exec(dedent("""
rch2 = rch.recv()
sch2 = rch.recv()
assert rch2 == rch
assert sch2 == sch
sch.send_nowait(rch2)
sch.send_nowait(sch2)
"""))
rch3 = rch.recv()
sch3 = rch.recv()
self.assertEqual(rch2, rch)
self.assertEqual(sch2, sch)
self.assertEqual(rch3, rch)
self.assertEqual(sch3, sch)
def test_is_closed(self):
rch, sch = channels.create()
rbefore = rch.is_closed
sbefore = sch.is_closed
rch.close()
rafter = rch.is_closed
safter = sch.is_closed
self.assertFalse(rbefore)
self.assertFalse(sbefore)
self.assertTrue(rafter)
self.assertTrue(safter)
class TestRecvChannelAttrs(TestBase):
def test_id_type(self):
rch, _ = channels.create()
self.assertIsInstance(rch.id, _channels.ChannelID)
def test_custom_id(self):
rch = channels.RecvChannel(1)
self.assertEqual(rch.id, 1)
with self.assertRaises(TypeError):
channels.RecvChannel('1')
def test_id_readonly(self):
rch = channels.RecvChannel(1)
with self.assertRaises(AttributeError):
rch.id = 2
def test_equality(self):
ch1, _ = channels.create()
ch2, _ = channels.create()
self.assertEqual(ch1, ch1)
self.assertNotEqual(ch1, ch2)
def test_pickle(self):
ch, _ = channels.create()
data = pickle.dumps(ch)
unpickled = pickle.loads(data)
self.assertEqual(unpickled, ch)
class TestSendChannelAttrs(TestBase):
def test_id_type(self):
_, sch = channels.create()
self.assertIsInstance(sch.id, _channels.ChannelID)
def test_custom_id(self):
sch = channels.SendChannel(1)
self.assertEqual(sch.id, 1)
with self.assertRaises(TypeError):
channels.SendChannel('1')
def test_id_readonly(self):
sch = channels.SendChannel(1)
with self.assertRaises(AttributeError):
sch.id = 2
def test_equality(self):
_, ch1 = channels.create()
_, ch2 = channels.create()
self.assertEqual(ch1, ch1)
self.assertNotEqual(ch1, ch2)
def test_pickle(self):
_, ch = channels.create()
data = pickle.dumps(ch)
unpickled = pickle.loads(data)
self.assertEqual(unpickled, ch)
class TestSendRecv(TestBase):
def test_send_recv_main(self):
r, s = channels.create()
orig = b'spam'
s.send_nowait(orig)
obj = r.recv()
self.assertEqual(obj, orig)
self.assertIsNot(obj, orig)
def test_send_recv_same_interpreter(self):
interp = interpreters.create()
interp.exec(dedent("""
from test.support import channels
r, s = channels.create()
orig = b'spam'
s.send_nowait(orig)
obj = r.recv()
assert obj == orig, 'expected: obj == orig'
assert obj is not orig, 'expected: obj is not orig'
"""))
@unittest.skip('broken (see BPO-...)')
def test_send_recv_different_interpreters(self):
r1, s1 = channels.create()
r2, s2 = channels.create()
orig1 = b'spam'
s1.send_nowait(orig1)
out = _run_output(
interpreters.create(),
dedent(f"""
obj1 = r.recv()
assert obj1 == b'spam', 'expected: obj1 == orig1'
# When going to another interpreter we get a copy.
assert id(obj1) != {id(orig1)}, 'expected: obj1 is not orig1'
orig2 = b'eggs'
print(id(orig2))
s.send_nowait(orig2)
"""),
channels=dict(r=r1, s=s2),
)
obj2 = r2.recv()
self.assertEqual(obj2, b'eggs')
self.assertNotEqual(id(obj2), int(out))
def test_send_recv_different_threads(self):
r, s = channels.create()
def f():
while True:
try:
obj = r.recv()
break
except channels.ChannelEmptyError:
time.sleep(0.1)
s.send(obj)
t = threading.Thread(target=f)
t.start()
orig = b'spam'
s.send(orig)
obj = r.recv()
t.join()
self.assertEqual(obj, orig)
self.assertIsNot(obj, orig)
def test_send_recv_nowait_main(self):
r, s = channels.create()
orig = b'spam'
s.send_nowait(orig)
obj = r.recv_nowait()
self.assertEqual(obj, orig)
self.assertIsNot(obj, orig)
def test_send_recv_nowait_main_with_default(self):
r, _ = channels.create()
obj = r.recv_nowait(None)
self.assertIsNone(obj)
def test_send_recv_nowait_same_interpreter(self):
interp = interpreters.create()
interp.exec(dedent("""
from test.support import channels
r, s = channels.create()
orig = b'spam'
s.send_nowait(orig)
obj = r.recv_nowait()
assert obj == orig, 'expected: obj == orig'
# When going back to the same interpreter we get the same object.
assert obj is not orig, 'expected: obj is not orig'
"""))
@unittest.skip('broken (see BPO-...)')
def test_send_recv_nowait_different_interpreters(self):
r1, s1 = channels.create()
r2, s2 = channels.create()
orig1 = b'spam'
s1.send_nowait(orig1)
out = _run_output(
interpreters.create(),
dedent(f"""
obj1 = r.recv_nowait()
assert obj1 == b'spam', 'expected: obj1 == orig1'
# When going to another interpreter we get a copy.
assert id(obj1) != {id(orig1)}, 'expected: obj1 is not orig1'
orig2 = b'eggs'
print(id(orig2))
s.send_nowait(orig2)
"""),
channels=dict(r=r1, s=s2),
)
obj2 = r2.recv_nowait()
self.assertEqual(obj2, b'eggs')
self.assertNotEqual(id(obj2), int(out))
def test_recv_timeout(self):
r, _ = channels.create()
with self.assertRaises(TimeoutError):
r.recv(timeout=1)
def test_recv_channel_does_not_exist(self):
ch = channels.RecvChannel(1_000_000)
with self.assertRaises(channels.ChannelNotFoundError):
ch.recv()
def test_send_channel_does_not_exist(self):
ch = channels.SendChannel(1_000_000)
with self.assertRaises(channels.ChannelNotFoundError):
ch.send(b'spam')
def test_recv_nowait_channel_does_not_exist(self):
ch = channels.RecvChannel(1_000_000)
with self.assertRaises(channels.ChannelNotFoundError):
ch.recv_nowait()
def test_send_nowait_channel_does_not_exist(self):
ch = channels.SendChannel(1_000_000)
with self.assertRaises(channels.ChannelNotFoundError):
ch.send_nowait(b'spam')
def test_recv_nowait_empty(self):
ch, _ = channels.create()
with self.assertRaises(channels.ChannelEmptyError):
ch.recv_nowait()
def test_recv_nowait_default(self):
default = object()
rch, sch = channels.create()
obj1 = rch.recv_nowait(default)
sch.send_nowait(None)
sch.send_nowait(1)
sch.send_nowait(b'spam')
sch.send_nowait(b'eggs')
obj2 = rch.recv_nowait(default)
obj3 = rch.recv_nowait(default)
obj4 = rch.recv_nowait()
obj5 = rch.recv_nowait(default)
obj6 = rch.recv_nowait(default)
self.assertIs(obj1, default)
self.assertIs(obj2, None)
self.assertEqual(obj3, 1)
self.assertEqual(obj4, b'spam')
self.assertEqual(obj5, b'eggs')
self.assertIs(obj6, default)
def test_send_buffer(self):
buf = bytearray(b'spamspamspam')
obj = None
rch, sch = channels.create()
def f():
nonlocal obj
while True:
try:
obj = rch.recv()
break
except channels.ChannelEmptyError:
time.sleep(0.1)
t = threading.Thread(target=f)
t.start()
sch.send_buffer(buf)
t.join()
self.assertIsNot(obj, buf)
self.assertIsInstance(obj, memoryview)
self.assertEqual(obj, buf)
buf[4:8] = b'eggs'
self.assertEqual(obj, buf)
obj[4:8] = b'ham.'
self.assertEqual(obj, buf)
def test_send_buffer_nowait(self):
buf = bytearray(b'spamspamspam')
rch, sch = channels.create()
sch.send_buffer_nowait(buf)
obj = rch.recv()
self.assertIsNot(obj, buf)
self.assertIsInstance(obj, memoryview)
self.assertEqual(obj, buf)
buf[4:8] = b'eggs'
self.assertEqual(obj, buf)
obj[4:8] = b'ham.'
self.assertEqual(obj, buf)
def test_send_cleared_with_subinterpreter(self):
def common(rch, sch, unbound=None, presize=0):
if not unbound:
extraargs = ''
elif unbound is channels.UNBOUND:
extraargs = ', unbounditems=channels.UNBOUND'
elif unbound is channels.UNBOUND_ERROR:
extraargs = ', unbounditems=channels.UNBOUND_ERROR'
elif unbound is channels.UNBOUND_REMOVE:
extraargs = ', unbounditems=channels.UNBOUND_REMOVE'
else:
raise NotImplementedError(repr(unbound))
interp = interpreters.create()
_run_output(interp, dedent(f"""
from test.support import channels
sch = channels.SendChannel({sch.id})
obj1 = b'spam'
obj2 = b'eggs'
sch.send_nowait(obj1{extraargs})
sch.send_nowait(obj2{extraargs})
"""))
self.assertEqual(
_channels.get_count(rch.id),
presize + 2,
)
if presize == 0:
obj1 = rch.recv()
self.assertEqual(obj1, b'spam')
self.assertEqual(
_channels.get_count(rch.id),
presize + 1,
)
return interp
with self.subTest('default'): # UNBOUND
rch, sch = channels.create()
interp = common(rch, sch)
del interp
self.assertEqual(_channels.get_count(rch.id), 1)
obj1 = rch.recv()
self.assertEqual(_channels.get_count(rch.id), 0)
self.assertIs(obj1, channels.UNBOUND)
self.assertEqual(_channels.get_count(rch.id), 0)
with self.assertRaises(channels.ChannelEmptyError):
rch.recv_nowait()
with self.subTest('UNBOUND'):
rch, sch = channels.create()
interp = common(rch, sch, channels.UNBOUND)
del interp
self.assertEqual(_channels.get_count(rch.id), 1)
obj1 = rch.recv()
self.assertIs(obj1, channels.UNBOUND)
self.assertEqual(_channels.get_count(rch.id), 0)
with self.assertRaises(channels.ChannelEmptyError):
rch.recv_nowait()
with self.subTest('UNBOUND_ERROR'):
rch, sch = channels.create()
interp = common(rch, sch, channels.UNBOUND_ERROR)
del interp
self.assertEqual(_channels.get_count(rch.id), 1)
with self.assertRaises(channels.ItemInterpreterDestroyed):
rch.recv()
self.assertEqual(_channels.get_count(rch.id), 0)
with self.assertRaises(channels.ChannelEmptyError):
rch.recv_nowait()
with self.subTest('UNBOUND_REMOVE'):
rch, sch = channels.create()
interp = common(rch, sch, channels.UNBOUND_REMOVE)
del interp
self.assertEqual(_channels.get_count(rch.id), 0)
with self.assertRaises(channels.ChannelEmptyError):
rch.recv_nowait()
sch.send_nowait(b'ham', unbounditems=channels.UNBOUND_REMOVE)
self.assertEqual(_channels.get_count(rch.id), 1)
interp = common(rch, sch, channels.UNBOUND_REMOVE, 1)
self.assertEqual(_channels.get_count(rch.id), 3)
sch.send_nowait(42, unbounditems=channels.UNBOUND_REMOVE)
self.assertEqual(_channels.get_count(rch.id), 4)
del interp
self.assertEqual(_channels.get_count(rch.id), 2)
obj1 = rch.recv()
obj2 = rch.recv()
self.assertEqual(obj1, b'ham')
self.assertEqual(obj2, 42)
self.assertEqual(_channels.get_count(rch.id), 0)
with self.assertRaises(channels.ChannelEmptyError):
rch.recv_nowait()
def test_send_cleared_with_subinterpreter_mixed(self):
rch, sch = channels.create()
interp = interpreters.create()
# If we don't associate the main interpreter with the channel
# then the channel will be automatically closed when interp
# is destroyed.
sch.send_nowait(None)
rch.recv()
self.assertEqual(_channels.get_count(rch.id), 0)
_run_output(interp, dedent(f"""
from test.support import channels
sch = channels.SendChannel({sch.id})
sch.send_nowait(1, unbounditems=channels.UNBOUND)
sch.send_nowait(2, unbounditems=channels.UNBOUND_ERROR)
sch.send_nowait(3)
sch.send_nowait(4, unbounditems=channels.UNBOUND_REMOVE)
sch.send_nowait(5, unbounditems=channels.UNBOUND)
"""))
self.assertEqual(_channels.get_count(rch.id), 5)
del interp
self.assertEqual(_channels.get_count(rch.id), 4)
obj1 = rch.recv()
self.assertIs(obj1, channels.UNBOUND)
self.assertEqual(_channels.get_count(rch.id), 3)
with self.assertRaises(channels.ItemInterpreterDestroyed):
rch.recv()
self.assertEqual(_channels.get_count(rch.id), 2)
obj2 = rch.recv()
self.assertIs(obj2, channels.UNBOUND)
self.assertEqual(_channels.get_count(rch.id), 1)
obj3 = rch.recv()
self.assertIs(obj3, channels.UNBOUND)
self.assertEqual(_channels.get_count(rch.id), 0)
def test_send_cleared_with_subinterpreter_multiple(self):
rch, sch = channels.create()
interp1 = interpreters.create()
interp2 = interpreters.create()
sch.send_nowait(1)
_run_output(interp1, dedent(f"""
from test.support import channels
rch = channels.RecvChannel({rch.id})
sch = channels.SendChannel({sch.id})
obj1 = rch.recv()
sch.send_nowait(2, unbounditems=channels.UNBOUND)
sch.send_nowait(obj1, unbounditems=channels.UNBOUND_REMOVE)
"""))
_run_output(interp2, dedent(f"""
from test.support import channels
rch = channels.RecvChannel({rch.id})
sch = channels.SendChannel({sch.id})
obj2 = rch.recv()
obj1 = rch.recv()
"""))
self.assertEqual(_channels.get_count(rch.id), 0)
sch.send_nowait(3)
_run_output(interp1, dedent("""
sch.send_nowait(4, unbounditems=channels.UNBOUND)
# interp closed here
sch.send_nowait(5, unbounditems=channels.UNBOUND_REMOVE)
sch.send_nowait(6, unbounditems=channels.UNBOUND)
"""))
_run_output(interp2, dedent("""
sch.send_nowait(7, unbounditems=channels.UNBOUND_ERROR)
# interp closed here
sch.send_nowait(obj1, unbounditems=channels.UNBOUND_ERROR)
sch.send_nowait(obj2, unbounditems=channels.UNBOUND_REMOVE)
sch.send_nowait(8, unbounditems=channels.UNBOUND)
"""))
_run_output(interp1, dedent("""
sch.send_nowait(9, unbounditems=channels.UNBOUND_REMOVE)
sch.send_nowait(10, unbounditems=channels.UNBOUND)
"""))
self.assertEqual(_channels.get_count(rch.id), 10)
obj3 = rch.recv()
self.assertEqual(obj3, 3)
self.assertEqual(_channels.get_count(rch.id), 9)
obj4 = rch.recv()
self.assertEqual(obj4, 4)
self.assertEqual(_channels.get_count(rch.id), 8)
del interp1
self.assertEqual(_channels.get_count(rch.id), 6)
# obj5 was removed
obj6 = rch.recv()
self.assertIs(obj6, channels.UNBOUND)
self.assertEqual(_channels.get_count(rch.id), 5)
obj7 = rch.recv()
self.assertEqual(obj7, 7)
self.assertEqual(_channels.get_count(rch.id), 4)
del interp2
self.assertEqual(_channels.get_count(rch.id), 3)
# obj1
with self.assertRaises(channels.ItemInterpreterDestroyed):
rch.recv()
self.assertEqual(_channels.get_count(rch.id), 2)
# obj2 was removed
obj8 = rch.recv()
self.assertIs(obj8, channels.UNBOUND)
self.assertEqual(_channels.get_count(rch.id), 1)
# obj9 was removed
obj10 = rch.recv()
self.assertIs(obj10, channels.UNBOUND)
self.assertEqual(_channels.get_count(rch.id), 0)
if __name__ == '__main__':
# Test needs to be a package, so we can do relative imports.
unittest.main()