1 files changed, 407 insertions, 0 deletions
diff --git a/venv/lib/python3.9/site-packages/trio/tests/test_channel.py b/venv/lib/python3.9/site-packages/trio/tests/test_channel.py
new file mode 100644
index 00000000..fd990fb3
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+++ b/venv/lib/python3.9/site-packages/trio/tests/test_channel.py
@@ -0,0 +1,407 @@
+import pytest
+
+from ..testing import wait_all_tasks_blocked, assert_checkpoints
+import trio
+from trio import open_memory_channel, EndOfChannel
+
+
+async def test_channel():
+    with pytest.raises(TypeError):
+        open_memory_channel(1.0)
+    with pytest.raises(ValueError):
+        open_memory_channel(-1)
+
+    s, r = open_memory_channel(2)
+    repr(s)  # smoke test
+    repr(r)  # smoke test
+
+    s.send_nowait(1)
+    with assert_checkpoints():
+        await s.send(2)
+    with pytest.raises(trio.WouldBlock):
+        s.send_nowait(None)
+
+    with assert_checkpoints():
+        assert await r.receive() == 1
+    assert r.receive_nowait() == 2
+    with pytest.raises(trio.WouldBlock):
+        r.receive_nowait()
+
+    s.send_nowait("last")
+    await s.aclose()
+    with pytest.raises(trio.ClosedResourceError):
+        await s.send("too late")
+    with pytest.raises(trio.ClosedResourceError):
+        s.send_nowait("too late")
+    with pytest.raises(trio.ClosedResourceError):
+        s.clone()
+    await s.aclose()
+
+    assert r.receive_nowait() == "last"
+    with pytest.raises(EndOfChannel):
+        await r.receive()
+    await r.aclose()
+    with pytest.raises(trio.ClosedResourceError):
+        await r.receive()
+    with pytest.raises(trio.ClosedResourceError):
+        await r.receive_nowait()
+    await r.aclose()
+
+
+async def test_553(autojump_clock):
+    s, r = open_memory_channel(1)
+    with trio.move_on_after(10) as timeout_scope:
+        await r.receive()
+    assert timeout_scope.cancelled_caught
+    await s.send("Test for PR #553")
+
+
+async def test_channel_multiple_producers():
+    async def producer(send_channel, i):
+        # We close our handle when we're done with it
+        async with send_channel:
+            for j in range(3 * i, 3 * (i + 1)):
+                await send_channel.send(j)
+
+    send_channel, receive_channel = open_memory_channel(0)
+    async with trio.open_nursery() as nursery:
+        # We hand out clones to all the new producers, and then close the
+        # original.
+        async with send_channel:
+            for i in range(10):
+                nursery.start_soon(producer, send_channel.clone(), i)
+
+        got = []
+        async for value in receive_channel:
+            got.append(value)
+
+        got.sort()
+        assert got == list(range(30))
+
+
+async def test_channel_multiple_consumers():
+    successful_receivers = set()
+    received = []
+
+    async def consumer(receive_channel, i):
+        async for value in receive_channel:
+            successful_receivers.add(i)
+            received.append(value)
+
+    async with trio.open_nursery() as nursery:
+        send_channel, receive_channel = trio.open_memory_channel(1)
+        async with send_channel:
+            for i in range(5):
+                nursery.start_soon(consumer, receive_channel, i)
+            await wait_all_tasks_blocked()
+            for i in range(10):
+                await send_channel.send(i)
+
+    assert successful_receivers == set(range(5))
+    assert len(received) == 10
+    assert set(received) == set(range(10))
+
+
+async def test_close_basics():
+    async def send_block(s, expect):
+        with pytest.raises(expect):
+            await s.send(None)
+
+    # closing send -> other send gets ClosedResourceError
+    s, r = open_memory_channel(0)
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(send_block, s, trio.ClosedResourceError)
+        await wait_all_tasks_blocked()
+        await s.aclose()
+
+    # and it's persistent
+    with pytest.raises(trio.ClosedResourceError):
+        s.send_nowait(None)
+    with pytest.raises(trio.ClosedResourceError):
+        await s.send(None)
+
+    # and receive gets EndOfChannel
+    with pytest.raises(EndOfChannel):
+        r.receive_nowait()
+    with pytest.raises(EndOfChannel):
+        await r.receive()
+
+    # closing receive -> send gets BrokenResourceError
+    s, r = open_memory_channel(0)
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(send_block, s, trio.BrokenResourceError)
+        await wait_all_tasks_blocked()
+        await r.aclose()
+
+    # and it's persistent
+    with pytest.raises(trio.BrokenResourceError):
+        s.send_nowait(None)
+    with pytest.raises(trio.BrokenResourceError):
+        await s.send(None)
+
+    # closing receive -> other receive gets ClosedResourceError
+    async def receive_block(r):
+        with pytest.raises(trio.ClosedResourceError):
+            await r.receive()
+
+    s, r = open_memory_channel(0)
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(receive_block, r)
+        await wait_all_tasks_blocked()
+        await r.aclose()
+
+    # and it's persistent
+    with pytest.raises(trio.ClosedResourceError):
+        r.receive_nowait()
+    with pytest.raises(trio.ClosedResourceError):
+        await r.receive()
+
+
+async def test_close_sync():
+    async def send_block(s, expect):
+        with pytest.raises(expect):
+            await s.send(None)
+
+    # closing send -> other send gets ClosedResourceError
+    s, r = open_memory_channel(0)
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(send_block, s, trio.ClosedResourceError)
+        await wait_all_tasks_blocked()
+        s.close()
+
+    # and it's persistent
+    with pytest.raises(trio.ClosedResourceError):
+        s.send_nowait(None)
+    with pytest.raises(trio.ClosedResourceError):
+        await s.send(None)
+
+    # and receive gets EndOfChannel
+    with pytest.raises(EndOfChannel):
+        r.receive_nowait()
+    with pytest.raises(EndOfChannel):
+        await r.receive()
+
+    # closing receive -> send gets BrokenResourceError
+    s, r = open_memory_channel(0)
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(send_block, s, trio.BrokenResourceError)
+        await wait_all_tasks_blocked()
+        r.close()
+
+    # and it's persistent
+    with pytest.raises(trio.BrokenResourceError):
+        s.send_nowait(None)
+    with pytest.raises(trio.BrokenResourceError):
+        await s.send(None)
+
+    # closing receive -> other receive gets ClosedResourceError
+    async def receive_block(r):
+        with pytest.raises(trio.ClosedResourceError):
+            await r.receive()
+
+    s, r = open_memory_channel(0)
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(receive_block, r)
+        await wait_all_tasks_blocked()
+        r.close()
+
+    # and it's persistent
+    with pytest.raises(trio.ClosedResourceError):
+        r.receive_nowait()
+    with pytest.raises(trio.ClosedResourceError):
+        await r.receive()
+
+
+async def test_receive_channel_clone_and_close():
+    s, r = open_memory_channel(10)
+
+    r2 = r.clone()
+    r3 = r.clone()
+
+    s.send_nowait(None)
+    await r.aclose()
+    with r2:
+        pass
+
+    with pytest.raises(trio.ClosedResourceError):
+        r.clone()
+
+    with pytest.raises(trio.ClosedResourceError):
+        r2.clone()
+
+    # Can still send, r3 is still open
+    s.send_nowait(None)
+
+    await r3.aclose()
+
+    # But now the receiver is really closed
+    with pytest.raises(trio.BrokenResourceError):
+        s.send_nowait(None)
+
+
+async def test_close_multiple_send_handles():
+    # With multiple send handles, closing one handle only wakes senders on
+    # that handle, but others can continue just fine
+    s1, r = open_memory_channel(0)
+    s2 = s1.clone()
+
+    async def send_will_close():
+        with pytest.raises(trio.ClosedResourceError):
+            await s1.send("nope")
+
+    async def send_will_succeed():
+        await s2.send("ok")
+
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(send_will_close)
+        nursery.start_soon(send_will_succeed)
+        await wait_all_tasks_blocked()
+        await s1.aclose()
+        assert await r.receive() == "ok"
+
+
+async def test_close_multiple_receive_handles():
+    # With multiple receive handles, closing one handle only wakes receivers on
+    # that handle, but others can continue just fine
+    s, r1 = open_memory_channel(0)
+    r2 = r1.clone()
+
+    async def receive_will_close():
+        with pytest.raises(trio.ClosedResourceError):
+            await r1.receive()
+
+    async def receive_will_succeed():
+        assert await r2.receive() == "ok"
+
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(receive_will_close)
+        nursery.start_soon(receive_will_succeed)
+        await wait_all_tasks_blocked()
+        await r1.aclose()
+        await s.send("ok")
+
+
+async def test_inf_capacity():
+    s, r = open_memory_channel(float("inf"))
+
+    # It's accepted, and we can send all day without blocking
+    with s:
+        for i in range(10):
+            s.send_nowait(i)
+
+    got = []
+    async for i in r:
+        got.append(i)
+    assert got == list(range(10))
+
+
+async def test_statistics():
+    s, r = open_memory_channel(2)
+
+    assert s.statistics() == r.statistics()
+    stats = s.statistics()
+    assert stats.current_buffer_used == 0
+    assert stats.max_buffer_size == 2
+    assert stats.open_send_channels == 1
+    assert stats.open_receive_channels == 1
+    assert stats.tasks_waiting_send == 0
+    assert stats.tasks_waiting_receive == 0
+
+    s.send_nowait(None)
+    assert s.statistics().current_buffer_used == 1
+
+    s2 = s.clone()
+    assert s.statistics().open_send_channels == 2
+    await s.aclose()
+    assert s2.statistics().open_send_channels == 1
+
+    r2 = r.clone()
+    assert s2.statistics().open_receive_channels == 2
+    await r2.aclose()
+    assert s2.statistics().open_receive_channels == 1
+
+    async with trio.open_nursery() as nursery:
+        s2.send_nowait(None)  # fill up the buffer
+        assert s.statistics().current_buffer_used == 2
+        nursery.start_soon(s2.send, None)
+        nursery.start_soon(s2.send, None)
+        await wait_all_tasks_blocked()
+        assert s.statistics().tasks_waiting_send == 2
+        nursery.cancel_scope.cancel()
+    assert s.statistics().tasks_waiting_send == 0
+
+    # empty out the buffer again
+    try:
+        while True:
+            r.receive_nowait()
+    except trio.WouldBlock:
+        pass
+
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(r.receive)
+        await wait_all_tasks_blocked()
+        assert s.statistics().tasks_waiting_receive == 1
+        nursery.cancel_scope.cancel()
+    assert s.statistics().tasks_waiting_receive == 0
+
+
+async def test_channel_fairness():
+
+    # We can remove an item we just sent, and send an item back in after, if
+    # no-one else is waiting.
+    s, r = open_memory_channel(1)
+    s.send_nowait(1)
+    assert r.receive_nowait() == 1
+    s.send_nowait(2)
+    assert r.receive_nowait() == 2
+
+    # But if someone else is waiting to receive, then they "own" the item we
+    # send, so we can't receive it (even though we run first):
+
+    result = None
+
+    async def do_receive(r):
+        nonlocal result
+        result = await r.receive()
+
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(do_receive, r)
+        await wait_all_tasks_blocked()
+        s.send_nowait(2)
+        with pytest.raises(trio.WouldBlock):
+            r.receive_nowait()
+    assert result == 2
+
+    # And the analogous situation for send: if we free up a space, we can't
+    # immediately send something in it if someone is already waiting to do
+    # that
+    s, r = open_memory_channel(1)
+    s.send_nowait(1)
+    with pytest.raises(trio.WouldBlock):
+        s.send_nowait(None)
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(s.send, 2)
+        await wait_all_tasks_blocked()
+        assert r.receive_nowait() == 1
+        with pytest.raises(trio.WouldBlock):
+            s.send_nowait(3)
+        assert (await r.receive()) == 2
+
+
+async def test_unbuffered():
+    s, r = open_memory_channel(0)
+    with pytest.raises(trio.WouldBlock):
+        r.receive_nowait()
+    with pytest.raises(trio.WouldBlock):
+        s.send_nowait(1)
+
+    async def do_send(s, v):
+        with assert_checkpoints():
+            await s.send(v)
+
+    async with trio.open_nursery() as nursery:
+        nursery.start_soon(do_send, s, 1)
+        with assert_checkpoints():
+            assert await r.receive() == 1
+    with pytest.raises(trio.WouldBlock):
+        r.receive_nowait()