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import pytest
 
from ... import _core
from ...testing import wait_all_tasks_blocked
from .._parking_lot import ParkingLot
from .tutil import check_sequence_matches
 
 
async def test_parking_lot_basic():
    record = []
 
    async def waiter(i, lot):
        record.append("sleep {}".format(i))
        await lot.park()
        record.append("wake {}".format(i))
 
    async with _core.open_nursery() as nursery:
        lot = ParkingLot()
        assert not lot
        assert len(lot) == 0
        assert lot.statistics().tasks_waiting == 0
        for i in range(3):
            nursery.start_soon(waiter, i, lot)
        await wait_all_tasks_blocked()
        assert len(record) == 3
        assert bool(lot)
        assert len(lot) == 3
        assert lot.statistics().tasks_waiting == 3
        lot.unpark_all()
        assert lot.statistics().tasks_waiting == 0
        await wait_all_tasks_blocked()
        assert len(record) == 6
 
    check_sequence_matches(
        record, [{"sleep 0", "sleep 1", "sleep 2"}, {"wake 0", "wake 1", "wake 2"}]
    )
 
    async with _core.open_nursery() as nursery:
        record = []
        for i in range(3):
            nursery.start_soon(waiter, i, lot)
            await wait_all_tasks_blocked()
        assert len(record) == 3
        for i in range(3):
            lot.unpark()
            await wait_all_tasks_blocked()
        # 1-by-1 wakeups are strict FIFO
        assert record == [
            "sleep 0",
            "sleep 1",
            "sleep 2",
            "wake 0",
            "wake 1",
            "wake 2",
        ]
 
    # It's legal (but a no-op) to try and unpark while there's nothing parked
    lot.unpark()
    lot.unpark(count=1)
    lot.unpark(count=100)
 
    # Check unpark with count
    async with _core.open_nursery() as nursery:
        record = []
        for i in range(3):
            nursery.start_soon(waiter, i, lot)
            await wait_all_tasks_blocked()
        lot.unpark(count=2)
        await wait_all_tasks_blocked()
        check_sequence_matches(
            record, ["sleep 0", "sleep 1", "sleep 2", {"wake 0", "wake 1"}]
        )
        lot.unpark_all()
 
 
async def cancellable_waiter(name, lot, scopes, record):
    with _core.CancelScope() as scope:
        scopes[name] = scope
        record.append("sleep {}".format(name))
        try:
            await lot.park()
        except _core.Cancelled:
            record.append("cancelled {}".format(name))
        else:
            record.append("wake {}".format(name))
 
 
async def test_parking_lot_cancel():
    record = []
    scopes = {}
 
    async with _core.open_nursery() as nursery:
        lot = ParkingLot()
        nursery.start_soon(cancellable_waiter, 1, lot, scopes, record)
        await wait_all_tasks_blocked()
        nursery.start_soon(cancellable_waiter, 2, lot, scopes, record)
        await wait_all_tasks_blocked()
        nursery.start_soon(cancellable_waiter, 3, lot, scopes, record)
        await wait_all_tasks_blocked()
        assert len(record) == 3
 
        scopes[2].cancel()
        await wait_all_tasks_blocked()
        assert len(record) == 4
        lot.unpark_all()
        await wait_all_tasks_blocked()
        assert len(record) == 6
 
    check_sequence_matches(
        record, ["sleep 1", "sleep 2", "sleep 3", "cancelled 2", {"wake 1", "wake 3"}]
    )
 
 
async def test_parking_lot_repark():
    record = []
    scopes = {}
    lot1 = ParkingLot()
    lot2 = ParkingLot()
 
    with pytest.raises(TypeError):
        lot1.repark([])
 
    async with _core.open_nursery() as nursery:
        nursery.start_soon(cancellable_waiter, 1, lot1, scopes, record)
        await wait_all_tasks_blocked()
        nursery.start_soon(cancellable_waiter, 2, lot1, scopes, record)
        await wait_all_tasks_blocked()
        nursery.start_soon(cancellable_waiter, 3, lot1, scopes, record)
        await wait_all_tasks_blocked()
        assert len(record) == 3
 
        assert len(lot1) == 3
        lot1.repark(lot2)
        assert len(lot1) == 2
        assert len(lot2) == 1
        lot2.unpark_all()
        await wait_all_tasks_blocked()
        assert len(record) == 4
        assert record == ["sleep 1", "sleep 2", "sleep 3", "wake 1"]
 
        lot1.repark_all(lot2)
        assert len(lot1) == 0
        assert len(lot2) == 2
 
        scopes[2].cancel()
        await wait_all_tasks_blocked()
        assert len(lot2) == 1
        assert record == [
            "sleep 1",
            "sleep 2",
            "sleep 3",
            "wake 1",
            "cancelled 2",
        ]
 
        lot2.unpark_all()
        await wait_all_tasks_blocked()
        assert record == [
            "sleep 1",
            "sleep 2",
            "sleep 3",
            "wake 1",
            "cancelled 2",
            "wake 3",
        ]
 
 
async def test_parking_lot_repark_with_count():
    record = []
    scopes = {}
    lot1 = ParkingLot()
    lot2 = ParkingLot()
    async with _core.open_nursery() as nursery:
        nursery.start_soon(cancellable_waiter, 1, lot1, scopes, record)
        await wait_all_tasks_blocked()
        nursery.start_soon(cancellable_waiter, 2, lot1, scopes, record)
        await wait_all_tasks_blocked()
        nursery.start_soon(cancellable_waiter, 3, lot1, scopes, record)
        await wait_all_tasks_blocked()
        assert len(record) == 3
 
        assert len(lot1) == 3
        assert len(lot2) == 0
        lot1.repark(lot2, count=2)
        assert len(lot1) == 1
        assert len(lot2) == 2
        while lot2:
            lot2.unpark()
            await wait_all_tasks_blocked()
        assert record == [
            "sleep 1",
            "sleep 2",
            "sleep 3",
            "wake 1",
            "wake 2",
        ]
        lot1.unpark_all()